[klibc] A port of gzip to klibc

A port of the gzip utility to klibc.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/usr/Kbuild b/usr/Kbuild
index fc5ce6a..f874f51 100644
--- a/usr/Kbuild
+++ b/usr/Kbuild
@@ -6,7 +6,7 @@
 
 include-subdir := include
 klibc-subdir := klibc
-usr-subdirs  := kinit utils dash
+usr-subdirs  := kinit utils dash gzip
 subdir-      := $(include-subdir) $(klibc-subdir) $(usr-subdirs)
 
 usr-subdirs  := $(addprefix _usr_,$(usr-subdirs))
diff --git a/usr/gzip/COPYING b/usr/gzip/COPYING
new file mode 100644
index 0000000..a43ea21
--- /dev/null
+++ b/usr/gzip/COPYING
@@ -0,0 +1,339 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                          675 Mass Ave, Cambridge, MA 02139, USA
+ Everyone is permitted to copy and distribute verbatim copies
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+
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+
+	Appendix: How to Apply These Terms to Your New Programs
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+  If you develop a new program, and you want it to be of the greatest
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+free software which everyone can redistribute and change under these terms.
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+    <one line to give the program's name and a brief idea of what it does.>
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+The hypothetical commands `show w' and `show c' should show the appropriate
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+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/usr/gzip/Kbuild b/usr/gzip/Kbuild
new file mode 100644
index 0000000..64fae04
--- /dev/null
+++ b/usr/gzip/Kbuild
@@ -0,0 +1,25 @@
+#
+# Kbuild file for gzip
+#
+
+# The gzip executable
+static-y := gzip
+gzip-y   := gzip.o util.o unzip.o inflate.o
+
+# Additional targets
+always := gunzip zcat
+
+# Optional ZIP support
+gzip-$(CONFIG_KLIB_ZIP)   += zip.o deflate.o trees.o bits.o
+cflags-$(CONFIG_KLIB_ZIP) += -DSUPPORT_ZIP
+EXTRA_KLIBCCFLAGS := $(cflags-y)
+
+# Additionally linked targets
+$(obj)/gunzip $(obj)/zcat: $(obj)/gzip
+	$(call cmd,ln)
+
+# Cleaning
+targets := gzip gzip.g gunzip zcat
+
+# Targets to install
+install-y := gzip gunzip zcat
diff --git a/usr/gzip/README b/usr/gzip/README
new file mode 100644
index 0000000..fdd7311
--- /dev/null
+++ b/usr/gzip/README
@@ -0,0 +1,144 @@
+This is the file README for the gzip distribution, version 1.2.4.
+
+gzip (GNU zip) is a compression utility designed to be a replacement
+for 'compress'. Its main advantages over compress are much better
+compression and freedom from patented algorithms.  The GNU Project
+uses it as the standard compression program for its system.
+
+gzip currently uses by default the LZ77 algorithm used in zip 1.9 (the
+portable pkzip compatible archiver). The gzip format was however
+designed to accommodate several compression algorithms. See below
+for a comparison of zip and gzip.
+
+gunzip can currently decompress files created by gzip, compress or
+pack. The detection of the input format is automatic.  For the
+gzip format, gunzip checks a 32 bit CRC. For pack, gunzip checks the
+uncompressed length.  The 'compress' format was not designed to allow
+consistency checks. However gunzip is sometimes able to detect a bad
+.Z file because there is some redundancy in the .Z compression format.
+If you get an error when uncompressing a .Z file, do not assume that
+the .Z file is correct simply because the standard uncompress does not
+complain.  This generally means that the standard uncompress does not
+check its input, and happily generates garbage output.
+
+gzip produces files with a .gz extension. Previous versions of gzip
+used the .z extension, which was already used by the 'pack'
+Huffman encoder. gunzip is able to decompress .z files (packed
+or gzip'ed).
+
+Several planned features are not yet supported (see the file TODO).
+See the file NEWS for a summary of changes since 0.5.  See the file
+INSTALL for installation instructions. Some answers to frequently
+asked questions are given in the file INSTALL, please read it. (In
+particular, please don't ask me once more for an /etc/magic entry.)
+
+WARNING: on several systems, compiler bugs cause gzip to fail, in
+particular when optimization options are on.  See the section "Special
+targets" at the end of the INSTALL file for a list of known problems.
+For all machines, use "make check" to check that gzip was compiled
+correctly.  Try compiling gzip without any optimization if you have a
+problem.
+
+Please send all comments and bug reports by electronic mail to:
+   Jean-loup Gailly <jloup@chorus.fr>
+
+or, if this fails, to bug-gnu-utils@prep.ai.mit.edu.
+Bug reports should ideally include:
+
+    * The complete output of "gzip -V" (or the contents of revision.h
+      if you can't get gzip to compile)
+    * The hardware and operating system (try "uname -a")
+    * The compiler used to compile (if it is gcc, use "gcc -v")
+    * A description of the bug behavior
+    * The input to gzip, that triggered the bug
+
+If you send me patches for machines I don't have access to, please test them
+very carefully. gzip is used for backups, it must be extremely reliable.
+
+The package crypt++.el is highly recommended to manipulate gzip'ed
+file from emacs. It recognizes automatically encrypted and compressed
+files when they are first visited or written. It is available via
+anonymous ftp to roebling.poly.edu [128.238.5.31] in /pub/crypt++.el.
+The same directory contains also patches to dired, ange-ftp and info.
+GNU tar 1.11.2 has a -z option to invoke directly gzip, so you don't have to
+patch it. The package ftp.uu.net:/languages/emacs-lisp/misc/jka-compr19.el.Z
+also supports gzip'ed files.
+
+The znew and gzexe shell scripts provided with gzip benefit from
+(but do not require) the cpmod utility to transfer file attributes.
+It is available by anonymous ftp on gatekeeper.dec.com in
+/.0/usenet/comp.sources.unix/volume11/cpmod.Z.
+
+The sample programs zread.c, sub.c and add.c in subdirectory sample
+are provided as examples of useful complements to gzip. Read the
+comments inside each source file.  The perl script ztouch is also
+provided as example (not installed by default since it relies on perl).
+
+
+gzip is free software, you can redistribute it and/or modify it under
+the terms of the GNU General Public License, a copy of which is
+provided under the name COPYING. The latest version of gzip are always
+available by ftp in prep.ai.mit.edu:/pub/gnu, or in any of the prep
+mirror sites:
+
+- sources in gzip-*.tar (or .shar or .tar.gz).
+- Solaris 2 executables in sparc-sun-solaris2/gzip-binaries-*.tar
+- MSDOS lha self-extracting exe in gzip-msdos-*.exe. Once extracted,
+  copy gzip.exe to gunzip.exe and zcat.exe, or use "gzip -d" to decompress.
+  gzip386.exe runs much faster but only on 386 and above; it is compiled with
+  djgpp 1.10 available in directory omnigate.clarkson.edu:/pub/msdos/djgpp.
+
+A VMS executable is available in ftp.spc.edu:[.macro32.savesets]gzip-1-*.zip
+(use [.macro32]unzip.exe to extract). A PRIMOS executable is available
+in ftp.lysator.liu.se:/pub/primos/run/gzip.run.
+OS/2 executables (16 and 32 bits versions) are available in
+ftp.tu-muenchen.de:/pub/comp/os/os2/archiver/gz*-[16,32].zip
+
+Some ftp servers can automatically make a tar.Z from a tar file. If
+you are getting gzip for the first time, you can ask for a tar.Z file
+instead of the much larger tar file.
+
+Many thanks to those who provided me with bug reports and feedback.
+See the files THANKS and ChangeLog for more details.
+
+
+		Note about zip vs. gzip:
+
+The name 'gzip' was a very unfortunate choice, because zip and gzip
+are two really different programs, although the actual compression and
+decompression sources were written by the same persons. A different
+name should have been used for gzip, but it is too late to change now.
+
+zip is an archiver: it compresses several files into a single archive
+file. gzip is a simple compressor: each file is compressed separately.
+Both share the same compression and decompression code for the
+'deflate' method.  unzip can also decompress old zip archives
+(implode, shrink and reduce methods). gunzip can also decompress files
+created by compress and pack. zip 1.9 and gzip do not support
+compression methods other than deflation. (zip 1.0 supports shrink and
+implode). Better compression methods may be added in future versions
+of gzip. zip will always stick to absolute compatibility with pkzip,
+it is thus constrained by PKWare, which is a commercial company.  The
+gzip header format is deliberately different from that of pkzip to
+avoid such a constraint.
+
+On Unix, gzip is mostly useful in combination with tar. GNU tar
+1.11.2 has a -z option to invoke gzip automatically.  "tar -z"
+compresses better than zip, since gzip can then take advantage of
+redundancy between distinct files. The drawback is that you must
+scan the whole tar.gz file in order to extract a single file near
+the end; unzip can directly seek to the end of the zip file. There
+is no overhead when you extract the whole archive anyway.
+If a member of a .zip archive is damaged, other files can still
+be recovered. If a .tar.gz file is damaged, files beyond the failure
+point cannot be recovered. (Future versions of gzip will have
+error recovery features.)
+
+gzip and gunzip are distributed as a single program. zip and unzip
+are, for historical reasons, two separate programs, although the
+authors of these two programs work closely together in the info-zip
+team. zip and unzip are not associated with the GNU project.
+The sources are available by ftp in
+
+	 oak.oakland.edu:/pub/misc/unix/zip19p1.zip
+	 oak.oakland.edu:/pub/misc/unix/unz50p1.tar-z
diff --git a/usr/gzip/bits.c b/usr/gzip/bits.c
new file mode 100644
index 0000000..4707a08
--- /dev/null
+++ b/usr/gzip/bits.c
@@ -0,0 +1,200 @@
+/* bits.c -- output variable-length bit strings
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+
+/*
+ *  PURPOSE
+ *
+ *      Output variable-length bit strings. Compression can be done
+ *      to a file or to memory. (The latter is not supported in this version.)
+ *
+ *  DISCUSSION
+ *
+ *      The PKZIP "deflate" file format interprets compressed file data
+ *      as a sequence of bits.  Multi-bit strings in the file may cross
+ *      byte boundaries without restriction.
+ *
+ *      The first bit of each byte is the low-order bit.
+ *
+ *      The routines in this file allow a variable-length bit value to
+ *      be output right-to-left (useful for literal values). For
+ *      left-to-right output (useful for code strings from the tree routines),
+ *      the bits must have been reversed first with bi_reverse().
+ *
+ *      For in-memory compression, the compressed bit stream goes directly
+ *      into the requested output buffer. The input data is read in blocks
+ *      by the mem_read() function. The buffer is limited to 64K on 16 bit
+ *      machines.
+ *
+ *  INTERFACE
+ *
+ *      void bi_init (FILE *zipfile)
+ *          Initialize the bit string routines.
+ *
+ *      void send_bits (int value, int length)
+ *          Write out a bit string, taking the source bits right to
+ *          left.
+ *
+ *      int bi_reverse (int value, int length)
+ *          Reverse the bits of a bit string, taking the source bits left to
+ *          right and emitting them right to left.
+ *
+ *      void bi_windup (void)
+ *          Write out any remaining bits in an incomplete byte.
+ *
+ *      void copy_block(char *buf, unsigned len, int header)
+ *          Copy a stored block to the zip file, storing first the length and
+ *          its one's complement if requested.
+ *
+ */
+
+#include "tailor.h"
+#include "gzip.h"
+
+#ifdef DEBUG
+#  include <stdio.h>
+#endif
+
+#ifdef RCSID
+static char rcsid[] = "$Id: bits.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+/* ===========================================================================
+ * Local data used by the "bit string" routines.
+ */
+
+local file_t zfile; /* output gzip file */
+
+local unsigned short bi_buf;
+/* Output buffer. bits are inserted starting at the bottom (least significant
+ * bits).
+ */
+
+#define Buf_size (8 * 2*sizeof(char))
+/* Number of bits used within bi_buf. (bi_buf might be implemented on
+ * more than 16 bits on some systems.)
+ */
+
+local int bi_valid;
+/* Number of valid bits in bi_buf.  All bits above the last valid bit
+ * are always zero.
+ */
+
+int (*read_buf) OF((char *buf, unsigned size));
+/* Current input function. Set to mem_read for in-memory compression */
+
+#ifdef DEBUG
+  ulg bits_sent;   /* bit length of the compressed data */
+#endif
+
+/* ===========================================================================
+ * Initialize the bit string routines.
+ */
+void bi_init (zipfile)
+    file_t zipfile; /* output zip file, NO_FILE for in-memory compression */
+{
+    zfile  = zipfile;
+    bi_buf = 0;
+    bi_valid = 0;
+#ifdef DEBUG
+    bits_sent = 0L;
+#endif
+
+    /* Set the defaults for file compression. They are set by memcompress
+     * for in-memory compression.
+     */
+    if (zfile != NO_FILE) {
+	read_buf  = file_read;
+    }
+}
+
+/* ===========================================================================
+ * Send a value on a given number of bits.
+ * IN assertion: length <= 16 and value fits in length bits.
+ */
+void send_bits(value, length)
+    int value;  /* value to send */
+    int length; /* number of bits */
+{
+#ifdef DEBUG
+    Tracev((stderr," l %2d v %4x ", length, value));
+    Assert(length > 0 && length <= 15, "invalid length");
+    bits_sent += (ulg)length;
+#endif
+    /* If not enough room in bi_buf, use (valid) bits from bi_buf and
+     * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
+     * unused bits in value.
+     */
+    if (bi_valid > (int)Buf_size - length) {
+        bi_buf |= (value << bi_valid);
+        put_short(bi_buf);
+        bi_buf = (ush)value >> (Buf_size - bi_valid);
+        bi_valid += length - Buf_size;
+    } else {
+        bi_buf |= value << bi_valid;
+        bi_valid += length;
+    }
+}
+
+/* ===========================================================================
+ * Reverse the first len bits of a code, using straightforward code (a faster
+ * method would use a table)
+ * IN assertion: 1 <= len <= 15
+ */
+unsigned bi_reverse(code, len)
+    unsigned code; /* the value to invert */
+    int len;       /* its bit length */
+{
+    register unsigned res = 0;
+    do {
+        res |= code & 1;
+        code >>= 1, res <<= 1;
+    } while (--len > 0);
+    return res >> 1;
+}
+
+/* ===========================================================================
+ * Write out any remaining bits in an incomplete byte.
+ */
+void bi_windup()
+{
+    if (bi_valid > 8) {
+        put_short(bi_buf);
+    } else if (bi_valid > 0) {
+        put_byte(bi_buf);
+    }
+    bi_buf = 0;
+    bi_valid = 0;
+#ifdef DEBUG
+    bits_sent = (bits_sent+7) & ~7;
+#endif
+}
+
+/* ===========================================================================
+ * Copy a stored block to the zip file, storing first the length and its
+ * one's complement if requested.
+ */
+void copy_block(buf, len, header)
+    char     *buf;    /* the input data */
+    unsigned len;     /* its length */
+    int      header;  /* true if block header must be written */
+{
+    bi_windup();              /* align on byte boundary */
+
+    if (header) {
+        put_short((ush)len);
+        put_short((ush)~len);
+#ifdef DEBUG
+        bits_sent += 2*16;
+#endif
+    }
+#ifdef DEBUG
+    bits_sent += (ulg)len<<3;
+#endif
+    while (len--) {
+	put_byte(*buf++);
+    }
+}
diff --git a/usr/gzip/deflate.c b/usr/gzip/deflate.c
new file mode 100644
index 0000000..1db44fd
--- /dev/null
+++ b/usr/gzip/deflate.c
@@ -0,0 +1,759 @@
+/* deflate.c -- compress data using the deflation algorithm
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/*
+ *  PURPOSE
+ *
+ *      Identify new text as repetitions of old text within a fixed-
+ *      length sliding window trailing behind the new text.
+ *
+ *  DISCUSSION
+ *
+ *      The "deflation" process depends on being able to identify portions
+ *      of the input text which are identical to earlier input (within a
+ *      sliding window trailing behind the input currently being processed).
+ *
+ *      The most straightforward technique turns out to be the fastest for
+ *      most input files: try all possible matches and select the longest.
+ *      The key feature of this algorithm is that insertions into the string
+ *      dictionary are very simple and thus fast, and deletions are avoided
+ *      completely. Insertions are performed at each input character, whereas
+ *      string matches are performed only when the previous match ends. So it
+ *      is preferable to spend more time in matches to allow very fast string
+ *      insertions and avoid deletions. The matching algorithm for small
+ *      strings is inspired from that of Rabin & Karp. A brute force approach
+ *      is used to find longer strings when a small match has been found.
+ *      A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
+ *      (by Leonid Broukhis).
+ *         A previous version of this file used a more sophisticated algorithm
+ *      (by Fiala and Greene) which is guaranteed to run in linear amortized
+ *      time, but has a larger average cost, uses more memory and is patented.
+ *      However the F&G algorithm may be faster for some highly redundant
+ *      files if the parameter max_chain_length (described below) is too large.
+ *
+ *  ACKNOWLEDGEMENTS
+ *
+ *      The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
+ *      I found it in 'freeze' written by Leonid Broukhis.
+ *      Thanks to many info-zippers for bug reports and testing.
+ *
+ *  REFERENCES
+ *
+ *      APPNOTE.TXT documentation file in PKZIP 1.93a distribution.
+ *
+ *      A description of the Rabin and Karp algorithm is given in the book
+ *         "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
+ *
+ *      Fiala,E.R., and Greene,D.H.
+ *         Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
+ *
+ *  INTERFACE
+ *
+ *      void lm_init (int pack_level, ush *flags)
+ *          Initialize the "longest match" routines for a new file
+ *
+ *      ulg deflate (void)
+ *          Processes a new input file and return its compressed length. Sets
+ *          the compressed length, crc, deflate flags and internal file
+ *          attributes.
+ */
+
+#include <stdio.h>
+
+#include "tailor.h"
+#include "gzip.h"
+
+#ifdef RCSID
+static char rcsid[] = "$Id: deflate.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+/* ===========================================================================
+ * Configuration parameters
+ */
+
+/* Compile with MEDIUM_MEM to reduce the memory requirements or
+ * with SMALL_MEM to use as little memory as possible. Use BIG_MEM if the
+ * entire input file can be held in memory (not possible on 16 bit systems).
+ * Warning: defining these symbols affects HASH_BITS (see below) and thus
+ * affects the compression ratio. The compressed output
+ * is still correct, and might even be smaller in some cases.
+ */
+
+#ifdef SMALL_MEM
+#   define HASH_BITS  13  /* Number of bits used to hash strings */
+#endif
+#ifdef MEDIUM_MEM
+#   define HASH_BITS  14
+#endif
+#ifndef HASH_BITS
+#   define HASH_BITS  15
+   /* For portability to 16 bit machines, do not use values above 15. */
+#endif
+
+/* To save space (see unlzw.c), we overlay prev+head with tab_prefix and
+ * window with tab_suffix. Check that we can do this:
+ */
+#if (WSIZE<<1) > (1<<BITS)
+   error: cannot overlay window with tab_suffix and prev with tab_prefix0
+#endif
+#if HASH_BITS > BITS-1
+   error: cannot overlay head with tab_prefix1
+#endif
+
+#define HASH_SIZE (unsigned)(1<<HASH_BITS)
+#define HASH_MASK (HASH_SIZE-1)
+#define WMASK     (WSIZE-1)
+/* HASH_SIZE and WSIZE must be powers of two */
+
+#define NIL 0
+/* Tail of hash chains */
+
+#define FAST 4
+#define SLOW 2
+/* speed options for the general purpose bit flag */
+
+#ifndef TOO_FAR
+#  define TOO_FAR 4096
+#endif
+/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
+
+/* ===========================================================================
+ * Local data used by the "longest match" routines.
+ */
+
+typedef ush Pos;
+typedef unsigned IPos;
+/* A Pos is an index in the character window. We use short instead of int to
+ * save space in the various tables. IPos is used only for parameter passing.
+ */
+
+/* DECLARE(uch, window, 2L*WSIZE); */
+/* Sliding window. Input bytes are read into the second half of the window,
+ * and move to the first half later to keep a dictionary of at least WSIZE
+ * bytes. With this organization, matches are limited to a distance of
+ * WSIZE-MAX_MATCH bytes, but this ensures that IO is always
+ * performed with a length multiple of the block size. Also, it limits
+ * the window size to 64K, which is quite useful on MSDOS.
+ * To do: limit the window size to WSIZE+BSZ if SMALL_MEM (the code would
+ * be less efficient).
+ */
+
+/* DECLARE(Pos, prev, WSIZE); */
+/* Link to older string with same hash index. To limit the size of this
+ * array to 64K, this link is maintained only for the last 32K strings.
+ * An index in this array is thus a window index modulo 32K.
+ */
+
+/* DECLARE(Pos, head, 1<<HASH_BITS); */
+/* Heads of the hash chains or NIL. */
+
+ulg window_size = (ulg)2*WSIZE;
+/* window size, 2*WSIZE except for MMAP or BIG_MEM, where it is the
+ * input file length plus MIN_LOOKAHEAD.
+ */
+
+long block_start;
+/* window position at the beginning of the current output block. Gets
+ * negative when the window is moved backwards.
+ */
+
+local unsigned ins_h;  /* hash index of string to be inserted */
+
+#define H_SHIFT  ((HASH_BITS+MIN_MATCH-1)/MIN_MATCH)
+/* Number of bits by which ins_h and del_h must be shifted at each
+ * input step. It must be such that after MIN_MATCH steps, the oldest
+ * byte no longer takes part in the hash key, that is:
+ *   H_SHIFT * MIN_MATCH >= HASH_BITS
+ */
+
+unsigned int prev_length;
+/* Length of the best match at previous step. Matches not greater than this
+ * are discarded. This is used in the lazy match evaluation.
+ */
+
+      unsigned      strstart;      /* start of string to insert */
+      unsigned      match_start;   /* start of matching string */
+local int           eofile;        /* flag set at end of input file */
+local unsigned      lookahead;     /* number of valid bytes ahead in window */
+
+unsigned max_chain_length;
+/* To speed up deflation, hash chains are never searched beyond this length.
+ * A higher limit improves compression ratio but degrades the speed.
+ */
+
+local unsigned int max_lazy_match;
+/* Attempt to find a better match only when the current match is strictly
+ * smaller than this value. This mechanism is used only for compression
+ * levels >= 4.
+ */
+#define max_insert_length  max_lazy_match
+/* Insert new strings in the hash table only if the match length
+ * is not greater than this length. This saves time but degrades compression.
+ * max_insert_length is used only for compression levels <= 3.
+ */
+
+local int compr_level;
+/* compression level (1..9) */
+
+unsigned good_match;
+/* Use a faster search when the previous match is longer than this */
+
+
+/* Values for max_lazy_match, good_match and max_chain_length, depending on
+ * the desired pack level (0..9). The values given below have been tuned to
+ * exclude worst case performance for pathological files. Better values may be
+ * found for specific files.
+ */
+
+typedef struct config {
+   ush good_length; /* reduce lazy search above this match length */
+   ush max_lazy;    /* do not perform lazy search above this match length */
+   ush nice_length; /* quit search above this match length */
+   ush max_chain;
+} config;
+
+#ifdef  FULL_SEARCH
+# define nice_match MAX_MATCH
+#else
+  int nice_match; /* Stop searching when current match exceeds this */
+#endif
+
+local config configuration_table[10] = {
+/*      good lazy nice chain */
+/* 0 */ {0,    0,  0,    0},  /* store only */
+/* 1 */ {4,    4,  8,    4},  /* maximum speed, no lazy matches */
+/* 2 */ {4,    5, 16,    8},
+/* 3 */ {4,    6, 32,   32},
+
+/* 4 */ {4,    4, 16,   16},  /* lazy matches */
+/* 5 */ {8,   16, 32,   32},
+/* 6 */ {8,   16, 128, 128},
+/* 7 */ {8,   32, 128, 256},
+/* 8 */ {32, 128, 258, 1024},
+/* 9 */ {32, 258, 258, 4096}}; /* maximum compression */
+
+/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
+ * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
+ * meaning.
+ */
+
+#define EQUAL 0
+/* result of memcmp for equal strings */
+
+/* ===========================================================================
+ *  Prototypes for local functions.
+ */
+local void fill_window   OF((void));
+local ulg deflate_fast   OF((void));
+
+      int  longest_match OF((IPos cur_match));
+#ifdef ASMV
+      void match_init OF((void)); /* asm code initialization */
+#endif
+
+#ifdef DEBUG
+local  void check_match OF((IPos start, IPos match, int length));
+#endif
+
+/* ===========================================================================
+ * Update a hash value with the given input byte
+ * IN  assertion: all calls to to UPDATE_HASH are made with consecutive
+ *    input characters, so that a running hash key can be computed from the
+ *    previous key instead of complete recalculation each time.
+ */
+#define UPDATE_HASH(h,c) (h = (((h)<<H_SHIFT) ^ (c)) & HASH_MASK)
+
+/* ===========================================================================
+ * Insert string s in the dictionary and set match_head to the previous head
+ * of the hash chain (the most recent string with same hash key). Return
+ * the previous length of the hash chain.
+ * IN  assertion: all calls to to INSERT_STRING are made with consecutive
+ *    input characters and the first MIN_MATCH bytes of s are valid
+ *    (except for the last MIN_MATCH-1 bytes of the input file).
+ */
+#define INSERT_STRING(s, match_head) \
+   (UPDATE_HASH(ins_h, window[(s) + MIN_MATCH-1]), \
+    prev[(s) & WMASK] = match_head = head[ins_h], \
+    head[ins_h] = (s))
+
+/* ===========================================================================
+ * Initialize the "longest match" routines for a new file
+ */
+void lm_init (pack_level, flags)
+    int pack_level; /* 0: store, 1: best speed, 9: best compression */
+    ush *flags;     /* general purpose bit flag */
+{
+    register unsigned j;
+
+    if (pack_level < 1 || pack_level > 9) error("bad pack level");
+    compr_level = pack_level;
+
+    /* Initialize the hash table. */
+    memzero((char*)head, HASH_SIZE*sizeof(*head));
+
+    /* prev will be initialized on the fly */
+
+    /* Set the default configuration parameters:
+     */
+    max_lazy_match   = configuration_table[pack_level].max_lazy;
+    good_match       = configuration_table[pack_level].good_length;
+#ifndef FULL_SEARCH
+    nice_match       = configuration_table[pack_level].nice_length;
+#endif
+    max_chain_length = configuration_table[pack_level].max_chain;
+    if (pack_level == 1) {
+       *flags |= FAST;
+    } else if (pack_level == 9) {
+       *flags |= SLOW;
+    }
+    /* ??? reduce max_chain_length for binary files */
+
+    strstart = 0;
+    block_start = 0L;
+#ifdef ASMV
+    match_init(); /* initialize the asm code */
+#endif
+
+    lookahead = read_buf((char*)window,
+			 sizeof(int) <= 2 ? (unsigned)WSIZE : 2*WSIZE);
+
+    if (lookahead == 0 || lookahead == (unsigned)EOF) {
+       eofile = 1, lookahead = 0;
+       return;
+    }
+    eofile = 0;
+    /* Make sure that we always have enough lookahead. This is important
+     * if input comes from a device such as a tty.
+     */
+    while (lookahead < MIN_LOOKAHEAD && !eofile) fill_window();
+
+    ins_h = 0;
+    for (j=0; j<MIN_MATCH-1; j++) UPDATE_HASH(ins_h, window[j]);
+    /* If lookahead < MIN_MATCH, ins_h is garbage, but this is
+     * not important since only literal bytes will be emitted.
+     */
+}
+
+/* ===========================================================================
+ * Set match_start to the longest match starting at the given string and
+ * return its length. Matches shorter or equal to prev_length are discarded,
+ * in which case the result is equal to prev_length and match_start is
+ * garbage.
+ * IN assertions: cur_match is the head of the hash chain for the current
+ *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
+ */
+#ifndef ASMV
+/* For MSDOS, OS/2 and 386 Unix, an optimized version is in match.asm or
+ * match.s. The code is functionally equivalent, so you can use the C version
+ * if desired.
+ */
+int longest_match(cur_match)
+    IPos cur_match;                             /* current match */
+{
+    unsigned chain_length = max_chain_length;   /* max hash chain length */
+    register uch *scan = window + strstart;     /* current string */
+    register uch *match;                        /* matched string */
+    register int len;                           /* length of current match */
+    int best_len = prev_length;                 /* best match length so far */
+    IPos limit = strstart > (IPos)MAX_DIST ? strstart - (IPos)MAX_DIST : NIL;
+    /* Stop when cur_match becomes <= limit. To simplify the code,
+     * we prevent matches with the string of window index 0.
+     */
+
+/* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
+ * It is easy to get rid of this optimization if necessary.
+ */
+#if HASH_BITS < 8 || MAX_MATCH != 258
+   error: Code too clever
+#endif
+
+#ifdef UNALIGNED_OK
+    /* Compare two bytes at a time. Note: this is not always beneficial.
+     * Try with and without -DUNALIGNED_OK to check.
+     */
+    register uch *strend = window + strstart + MAX_MATCH - 1;
+    register ush scan_start = *(ush*)scan;
+    register ush scan_end   = *(ush*)(scan+best_len-1);
+#else
+    register uch *strend = window + strstart + MAX_MATCH;
+    register uch scan_end1  = scan[best_len-1];
+    register uch scan_end   = scan[best_len];
+#endif
+
+    /* Do not waste too much time if we already have a good match: */
+    if (prev_length >= good_match) {
+        chain_length >>= 2;
+    }
+    Assert(strstart <= window_size-MIN_LOOKAHEAD, "insufficient lookahead");
+
+    do {
+        Assert(cur_match < strstart, "no future");
+        match = window + cur_match;
+
+        /* Skip to next match if the match length cannot increase
+         * or if the match length is less than 2:
+         */
+#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
+        /* This code assumes sizeof(unsigned short) == 2. Do not use
+         * UNALIGNED_OK if your compiler uses a different size.
+         */
+        if (*(ush*)(match+best_len-1) != scan_end ||
+            *(ush*)match != scan_start) continue;
+
+        /* It is not necessary to compare scan[2] and match[2] since they are
+         * always equal when the other bytes match, given that the hash keys
+         * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
+         * strstart+3, +5, ... up to strstart+257. We check for insufficient
+         * lookahead only every 4th comparison; the 128th check will be made
+         * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
+         * necessary to put more guard bytes at the end of the window, or
+         * to check more often for insufficient lookahead.
+         */
+        scan++, match++;
+        do {
+        } while (*(ush*)(scan+=2) == *(ush*)(match+=2) &&
+                 *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+                 *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+                 *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+                 scan < strend);
+        /* The funny "do {}" generates better code on most compilers */
+
+        /* Here, scan <= window+strstart+257 */
+        Assert(scan <= window+(unsigned)(window_size-1), "wild scan");
+        if (*scan == *match) scan++;
+
+        len = (MAX_MATCH - 1) - (int)(strend-scan);
+        scan = strend - (MAX_MATCH-1);
+
+#else /* UNALIGNED_OK */
+
+        if (match[best_len]   != scan_end  ||
+            match[best_len-1] != scan_end1 ||
+            *match            != *scan     ||
+            *++match          != scan[1])      continue;
+
+        /* The check at best_len-1 can be removed because it will be made
+         * again later. (This heuristic is not always a win.)
+         * It is not necessary to compare scan[2] and match[2] since they
+         * are always equal when the other bytes match, given that
+         * the hash keys are equal and that HASH_BITS >= 8.
+         */
+        scan += 2, match++;
+
+        /* We check for insufficient lookahead only every 8th comparison;
+         * the 256th check will be made at strstart+258.
+         */
+        do {
+        } while (*++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 scan < strend);
+
+        len = MAX_MATCH - (int)(strend - scan);
+        scan = strend - MAX_MATCH;
+
+#endif /* UNALIGNED_OK */
+
+        if (len > best_len) {
+            match_start = cur_match;
+            best_len = len;
+            if (len >= nice_match) break;
+#ifdef UNALIGNED_OK
+            scan_end = *(ush*)(scan+best_len-1);
+#else
+            scan_end1  = scan[best_len-1];
+            scan_end   = scan[best_len];
+#endif
+        }
+    } while ((cur_match = prev[cur_match & WMASK]) > limit
+	     && --chain_length != 0);
+
+    return best_len;
+}
+#endif /* ASMV */
+
+#ifdef DEBUG
+/* ===========================================================================
+ * Check that the match at match_start is indeed a match.
+ */
+local void check_match(start, match, length)
+    IPos start, match;
+    int length;
+{
+    /* check that the match is indeed a match */
+    if (memcmp((char*)window + match,
+                (char*)window + start, length) != EQUAL) {
+        fprintf(stderr,
+            " start %d, match %d, length %d\n",
+            start, match, length);
+        error("invalid match");
+    }
+    if (verbose > 1) {
+        fprintf(stderr,"\\[%d,%d]", start-match, length);
+        do { putc(window[start++], stderr); } while (--length != 0);
+    }
+}
+#else
+#  define check_match(start, match, length)
+#endif
+
+/* ===========================================================================
+ * Fill the window when the lookahead becomes insufficient.
+ * Updates strstart and lookahead, and sets eofile if end of input file.
+ * IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0
+ * OUT assertions: at least one byte has been read, or eofile is set;
+ *    file reads are performed for at least two bytes (required for the
+ *    translate_eol option).
+ */
+local void fill_window()
+{
+    register unsigned n, m;
+    unsigned more = (unsigned)(window_size - (ulg)lookahead - (ulg)strstart);
+    /* Amount of free space at the end of the window. */
+
+    /* If the window is almost full and there is insufficient lookahead,
+     * move the upper half to the lower one to make room in the upper half.
+     */
+    if (more == (unsigned)EOF) {
+        /* Very unlikely, but possible on 16 bit machine if strstart == 0
+         * and lookahead == 1 (input done one byte at time)
+         */
+        more--;
+    } else if (strstart >= WSIZE+MAX_DIST) {
+        /* By the IN assertion, the window is not empty so we can't confuse
+         * more == 0 with more == 64K on a 16 bit machine.
+         */
+        Assert(window_size == (ulg)2*WSIZE, "no sliding with BIG_MEM");
+
+        memcpy((char*)window, (char*)window+WSIZE, (unsigned)WSIZE);
+        match_start -= WSIZE;
+        strstart    -= WSIZE; /* we now have strstart >= MAX_DIST: */
+
+        block_start -= (long) WSIZE;
+
+        for (n = 0; n < HASH_SIZE; n++) {
+            m = head[n];
+            head[n] = (Pos)(m >= WSIZE ? m-WSIZE : NIL);
+        }
+        for (n = 0; n < WSIZE; n++) {
+            m = prev[n];
+            prev[n] = (Pos)(m >= WSIZE ? m-WSIZE : NIL);
+            /* If n is not on any hash chain, prev[n] is garbage but
+             * its value will never be used.
+             */
+        }
+        more += WSIZE;
+    }
+    /* At this point, more >= 2 */
+    if (!eofile) {
+        n = read_buf((char*)window+strstart+lookahead, more);
+        if (n == 0 || n == (unsigned)EOF) {
+            eofile = 1;
+        } else {
+            lookahead += n;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Flush the current block, with given end-of-file flag.
+ * IN assertion: strstart is set to the end of the current match.
+ */
+#define FLUSH_BLOCK(eof) \
+   flush_block(block_start >= 0L ? (char*)&window[(unsigned)block_start] : \
+                (char*)NULL, (long)strstart - block_start, (eof))
+
+/* ===========================================================================
+ * Processes a new input file and return its compressed length. This
+ * function does not perform lazy evaluationof matches and inserts
+ * new strings in the dictionary only for unmatched strings or for short
+ * matches. It is used only for the fast compression options.
+ */
+local ulg deflate_fast()
+{
+    IPos hash_head; /* head of the hash chain */
+    int flush;      /* set if current block must be flushed */
+    unsigned match_length = 0;  /* length of best match */
+
+    prev_length = MIN_MATCH-1;
+    while (lookahead != 0) {
+        /* Insert the string window[strstart .. strstart+2] in the
+         * dictionary, and set hash_head to the head of the hash chain:
+         */
+        INSERT_STRING(strstart, hash_head);
+
+        /* Find the longest match, discarding those <= prev_length.
+         * At this point we have always match_length < MIN_MATCH
+         */
+        if (hash_head != NIL && strstart - hash_head <= MAX_DIST) {
+            /* To simplify the code, we prevent matches with the string
+             * of window index 0 (in particular we have to avoid a match
+             * of the string with itself at the start of the input file).
+             */
+            match_length = longest_match (hash_head);
+            /* longest_match() sets match_start */
+            if (match_length > lookahead) match_length = lookahead;
+        }
+        if (match_length >= MIN_MATCH) {
+            check_match(strstart, match_start, match_length);
+
+            flush = ct_tally(strstart-match_start, match_length - MIN_MATCH);
+
+            lookahead -= match_length;
+
+	    /* Insert new strings in the hash table only if the match length
+             * is not too large. This saves time but degrades compression.
+             */
+            if (match_length <= max_insert_length) {
+                match_length--; /* string at strstart already in hash table */
+                do {
+                    strstart++;
+                    INSERT_STRING(strstart, hash_head);
+                    /* strstart never exceeds WSIZE-MAX_MATCH, so there are
+                     * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
+                     * these bytes are garbage, but it does not matter since
+                     * the next lookahead bytes will be emitted as literals.
+                     */
+                } while (--match_length != 0);
+	        strstart++;
+            } else {
+	        strstart += match_length;
+	        match_length = 0;
+	        ins_h = window[strstart];
+	        UPDATE_HASH(ins_h, window[strstart+1]);
+#if MIN_MATCH != 3
+                Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+            }
+        } else {
+            /* No match, output a literal byte */
+            Tracevv((stderr,"%c",window[strstart]));
+            flush = ct_tally (0, window[strstart]);
+            lookahead--;
+	    strstart++;
+        }
+        if (flush) FLUSH_BLOCK(0), block_start = strstart;
+
+        /* Make sure that we always have enough lookahead, except
+         * at the end of the input file. We need MAX_MATCH bytes
+         * for the next match, plus MIN_MATCH bytes to insert the
+         * string following the next match.
+         */
+        while (lookahead < MIN_LOOKAHEAD && !eofile) fill_window();
+
+    }
+    return FLUSH_BLOCK(1); /* eof */
+}
+
+/* ===========================================================================
+ * Same as above, but achieves better compression. We use a lazy
+ * evaluation for matches: a match is finally adopted only if there is
+ * no better match at the next window position.
+ */
+ulg deflate()
+{
+    IPos hash_head;          /* head of hash chain */
+    IPos prev_match;         /* previous match */
+    int flush;               /* set if current block must be flushed */
+    int match_available = 0; /* set if previous match exists */
+    register unsigned match_length = MIN_MATCH-1; /* length of best match */
+#ifdef DEBUG
+    extern long isize;        /* byte length of input file, for debug only */
+#endif
+
+    if (compr_level <= 3) return deflate_fast(); /* optimized for speed */
+
+    /* Process the input block. */
+    while (lookahead != 0) {
+        /* Insert the string window[strstart .. strstart+2] in the
+         * dictionary, and set hash_head to the head of the hash chain:
+         */
+        INSERT_STRING(strstart, hash_head);
+
+        /* Find the longest match, discarding those <= prev_length.
+         */
+        prev_length = match_length, prev_match = match_start;
+        match_length = MIN_MATCH-1;
+
+        if (hash_head != NIL && prev_length < max_lazy_match &&
+            strstart - hash_head <= MAX_DIST) {
+            /* To simplify the code, we prevent matches with the string
+             * of window index 0 (in particular we have to avoid a match
+             * of the string with itself at the start of the input file).
+             */
+            match_length = longest_match (hash_head);
+            /* longest_match() sets match_start */
+            if (match_length > lookahead) match_length = lookahead;
+
+            /* Ignore a length 3 match if it is too distant: */
+            if (match_length == MIN_MATCH && strstart-match_start > TOO_FAR){
+                /* If prev_match is also MIN_MATCH, match_start is garbage
+                 * but we will ignore the current match anyway.
+                 */
+                match_length--;
+            }
+        }
+        /* If there was a match at the previous step and the current
+         * match is not better, output the previous match:
+         */
+        if (prev_length >= MIN_MATCH && match_length <= prev_length) {
+
+            check_match(strstart-1, prev_match, prev_length);
+
+            flush = ct_tally(strstart-1-prev_match, prev_length - MIN_MATCH);
+
+            /* Insert in hash table all strings up to the end of the match.
+             * strstart-1 and strstart are already inserted.
+             */
+            lookahead -= prev_length-1;
+            prev_length -= 2;
+            do {
+                strstart++;
+                INSERT_STRING(strstart, hash_head);
+                /* strstart never exceeds WSIZE-MAX_MATCH, so there are
+                 * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
+                 * these bytes are garbage, but it does not matter since the
+                 * next lookahead bytes will always be emitted as literals.
+                 */
+            } while (--prev_length != 0);
+            match_available = 0;
+            match_length = MIN_MATCH-1;
+            strstart++;
+            if (flush) FLUSH_BLOCK(0), block_start = strstart;
+
+        } else if (match_available) {
+            /* If there was no match at the previous position, output a
+             * single literal. If there was a match but the current match
+             * is longer, truncate the previous match to a single literal.
+             */
+            Tracevv((stderr,"%c",window[strstart-1]));
+            if (ct_tally (0, window[strstart-1])) {
+                FLUSH_BLOCK(0), block_start = strstart;
+            }
+            strstart++;
+            lookahead--;
+        } else {
+            /* There is no previous match to compare with, wait for
+             * the next step to decide.
+             */
+            match_available = 1;
+            strstart++;
+            lookahead--;
+        }
+        Assert (strstart <= isize && lookahead <= isize, "a bit too far");
+
+        /* Make sure that we always have enough lookahead, except
+         * at the end of the input file. We need MAX_MATCH bytes
+         * for the next match, plus MIN_MATCH bytes to insert the
+         * string following the next match.
+         */
+        while (lookahead < MIN_LOOKAHEAD && !eofile) fill_window();
+    }
+    if (match_available) ct_tally (0, window[strstart-1]);
+
+    return FLUSH_BLOCK(1); /* eof */
+}
diff --git a/usr/gzip/gzip.c b/usr/gzip/gzip.c
new file mode 100644
index 0000000..8f4c121
--- /dev/null
+++ b/usr/gzip/gzip.c
@@ -0,0 +1,1214 @@
+/* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * The unzip code was written and put in the public domain by Mark Adler.
+ * Portions of the lzw code are derived from the public domain 'compress'
+ * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
+ * Ken Turkowski, Dave Mack and Peter Jannesen.
+ *
+ * See the license_msg below and the file COPYING for the software license.
+ * See the file algorithm.doc for the compression algorithms and file formats.
+ */
+
+static char  *license_msg[] = {
+"   Copyright (C) 1992-1993 Jean-loup Gailly",
+"   This program is free software; you can redistribute it and/or modify",
+"   it under the terms of the GNU General Public License as published by",
+"   the Free Software Foundation; either version 2, or (at your option)",
+"   any later version.",
+"",
+"   This program is distributed in the hope that it will be useful,",
+"   but WITHOUT ANY WARRANTY; without even the implied warranty of",
+"   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the",
+"   GNU General Public License for more details.",
+"",
+"   You should have received a copy of the GNU General Public License",
+"   along with this program; if not, write to the Free Software",
+"   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.",
+0};
+
+/* Compress files with zip algorithm and 'compress' interface.
+ * See usage() and help() functions below for all options.
+ * Outputs:
+ *        file.gz:   compressed file with same mode, owner, and utimes
+ *     or stdout with -c option or if stdin used as input.
+ * If the output file name had to be truncated, the original name is kept
+ * in the compressed file.
+ * On MSDOS, file.tmp -> file.tmz. On VMS, file.tmp -> file.tmp-gz.
+ *
+ * Using gz on MSDOS would create too many file name conflicts. For
+ * example, foo.txt -> foo.tgz (.tgz must be reserved as shorthand for
+ * tar.gz). Similarly, foo.dir and foo.doc would both be mapped to foo.dgz.
+ * I also considered 12345678.txt -> 12345txt.gz but this truncates the name
+ * too heavily. There is no ideal solution given the MSDOS 8+3 limitation.
+ *
+ * For the meaning of all compilation flags, see comments in Makefile.in.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: gzip.c,v 1.3 2005/02/12 21:03:28 olh Exp $";
+#endif
+
+#include <ctype.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+#include "tailor.h"
+#include "gzip.h"
+#include "revision.h"
+
+#include <time.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include <utime.h>
+
+typedef void (*sig_type) OF((int));
+
+#define RW_USER (S_IRUSR | S_IWUSR)  /* creation mode for open() */
+
+#ifndef MAX_PATH_LEN
+#  define MAX_PATH_LEN   1024 /* max pathname length */
+#endif
+
+		/* global buffers */
+
+DECLARE(uch, inbuf,  INBUFSIZ +INBUF_EXTRA);
+DECLARE(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
+DECLARE(ush, d_buf,  DIST_BUFSIZE);
+DECLARE(uch, window, 2L*WSIZE);
+DECLARE(ush, tab_prefix, 1L<<BITS);
+
+		/* local variables */
+
+#ifndef SUPPORT_ZIP
+#define decompress 1
+#else
+int level = 6;        /* compression level */
+#endif
+
+int to_stdout;        /* output to stdout (-c) */
+#ifndef decompress
+int decompress;       /* decompress (-d) */
+#endif
+int force;            /* don't ask questions, compress links (-f) */
+int no_name = -1;     /* don't save or restore the original file name */
+int no_time = -1;     /* don't save or restore the original file time */
+int verbose;          /* be verbose (-v) */
+int quiet;            /* be very quiet (-q) */
+int test;             /* test .gz file integrity */
+int foreground;       /* set if program run in foreground */
+char *progname;       /* program name */
+int method = DEFLATED;/* compression method */
+int exit_code = OK;   /* program exit code */
+int save_orig_name;   /* set if original name must be saved */
+int last_member;      /* set for .zip and .Z files */
+int part_nb;          /* number of parts in .gz file */
+time_t time_stamp; /* original time stamp (modification time) */
+long ifile_size;      /* input file size, -1 for devices (debug only) */
+char *env;            /* contents of GZIP env variable */
+char **args = NULL;   /* argv pointer if GZIP env variable defined */
+char z_suffix[MAX_SUFFIX+1]; /* default suffix (can be set with --suffix) */
+int  z_len;           /* strlen(z_suffix) */
+
+long header_bytes;	   /* number of bytes in gzip header */
+long bytes_in;             /* number of input bytes */
+long bytes_out;            /* number of output bytes */
+long total_in;             /* input bytes for all files */
+long total_out;            /* output bytes for all files */
+char ifname[MAX_PATH_LEN]; /* input file name */
+char ofname[MAX_PATH_LEN]; /* output file name */
+int  remove_ofname;	   /* remove output file on error */
+struct stat istat;         /* status for input file */
+int  ifd;                  /* input file descriptor */
+int  ofd;                  /* output file descriptor */
+unsigned insize;           /* valid bytes in inbuf */
+unsigned inptr;            /* index of next byte to be processed in inbuf */
+unsigned outcnt;           /* bytes in output buffer */
+
+/* local functions */
+
+local void usage        OF((void));
+local void help         OF((void));
+local void license      OF((void));
+local void version      OF((void));
+local void treat_stdin  OF((void));
+local void treat_file   OF((char *iname));
+local int create_outfile OF((void));
+local int  do_stat      OF((char *name, struct stat *sbuf));
+local char *get_suffix  OF((char *name));
+local int  get_istat    OF((char *iname, struct stat *sbuf));
+local int  make_ofname  OF((void));
+local int  same_file    OF((struct stat *stat1, struct stat *stat2));
+local int name_too_long OF((char *name, struct stat *statb));
+local void shorten_name  OF((char *name));
+local int  get_method   OF((void));
+local int  check_ofname OF((void));
+local void copy_stat    OF((struct stat *ifstat));
+local void do_exit      OF((int exitcode));
+      int main          OF((int argc, char **argv));
+int (*work) OF((int infile, int outfile))
+#ifdef SUPPORT_ZIP
+ = zip; /* function to call */
+#else
+ = unzip;
+#endif
+local void reset_times  OF((char *name, struct stat *statb));
+
+#define strequ(s1, s2) (strcmp((s1),(s2)) == 0)
+
+/* ======================================================================== */
+local void usage()
+{
+    fprintf(stderr, "usage: %s [-cdfhlLnNtvV19] [-S suffix] [file ...]\n",
+	    progname);
+}
+
+/* ======================================================================== */
+local void help()
+{
+    static char  *help_msg[] = {
+ " -c --stdout      write on standard output, keep original files unchanged",
+ " -d --decompress  decompress",
+ " -f --force       force overwrite of output file and compress links",
+ " -h --help        give this help",
+ " -L --license     display software license",
+#ifdef UNDOCUMENTED
+ " -m --no-time     do not save or restore the original modification time",
+ " -M --time        save or restore the original modification time",
+#endif
+ " -n --no-name     do not save or restore the original name and time stamp",
+ " -N --name        save or restore the original name and time stamp",
+ " -q --quiet       suppress all warnings",
+ " -S .suf  --suffix .suf     use suffix .suf on compressed files",
+ " -t --test        test compressed file integrity",
+ " -v --verbose     verbose mode",
+ " -V --version     display version number",
+#ifdef SUPPORT_ZIP
+ " -1 --fast        compress faster",
+ " -9 --best        compress better",
+ " file...          files to (de)compress. If none given, use standard input.",
+#else
+ " file...          files to decompress. If none given, use standard input.",
+#endif
+  0};
+    char **p = help_msg;
+
+    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);
+    usage();
+    while (*p) fprintf(stderr, "%s\n", *p++);
+}
+
+/* ======================================================================== */
+local void license()
+{
+    char **p = license_msg;
+
+    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);
+    while (*p) fprintf(stderr, "%s\n", *p++);
+}
+
+/* ======================================================================== */
+local void version()
+{
+    fprintf(stderr,"%s %s (%s)\n", progname, VERSION, REVDATE);
+
+    fprintf(stderr, "Compilation options: UTIME STDC_HEADERS"
+#ifndef SUPPORT_ZIP
+	" DECOMPRESS_ONLY"
+#endif
+	"\n");
+}
+
+/* ======================================================================== */
+int main (argc, argv)
+    int argc;
+    char **argv;
+{
+    int file_count;     /* number of files to precess */
+    int proglen;        /* length of progname */
+    int optc;           /* current option */
+
+    progname = basename(argv[0]);
+    proglen = strlen(progname);
+
+    /* Add options in GZIP environment variable if there is one */
+    env = add_envopt(&argc, &argv, OPTIONS_VAR);
+    if (env != NULL) args = argv;
+
+    foreground = sysv_signal(SIGINT, SIG_IGN) != SIG_IGN;
+    if (foreground) {
+	(void) sysv_signal(SIGINT, (sig_type)abort_gzip);
+    }
+#ifdef SIGTERM
+    if (sysv_signal(SIGTERM, SIG_IGN) != SIG_IGN) {
+	(void) sysv_signal(SIGTERM, (sig_type)abort_gzip);
+    }
+#endif
+#ifdef SIGHUP
+    if (sysv_signal(SIGHUP, SIG_IGN) != SIG_IGN) {
+	(void) sysv_signal(SIGHUP,  (sig_type)abort_gzip);
+    }
+#endif
+
+#ifndef GNU_STANDARD
+    /* For compatibility with old compress, use program name as an option.
+     * If you compile with -DGNU_STANDARD, this program will behave as
+     * gzip even if it is invoked under the name gunzip or zcat.
+     *
+     * Systems which do not support links can still use -d or -dc.
+     * Ignore an .exe extension for MSDOS, OS/2 and VMS.
+     */
+#ifndef decompress
+    if (  strncmp(progname, "un",  2) == 0     /* ungzip, uncompress */
+       || strncmp(progname, "gun", 3) == 0) {  /* gunzip */
+	decompress = 1;
+    }
+#endif
+    if (strequ(progname+1, "cat")       /* zcat, pcat, gcat */
+	|| strequ(progname, "gzcat")) {    /* gzcat */
+#ifndef decompress
+	decompress = 1;
+#endif
+	to_stdout = 1;
+    }
+#endif
+
+    strncpy(z_suffix, Z_SUFFIX, sizeof(z_suffix)-1);
+    z_len = strlen(z_suffix);
+
+    while ((optc = getopt(argc, argv, "cdfhH?LmMnNqrS:tvV123456789")) != EOF) {
+	switch (optc) {
+	case 'c':
+	    to_stdout = 1; break;
+	case 'd':
+#ifndef decompress
+	    decompress = 1;
+#endif
+	    break;
+	case 'f':
+	    force++; break;
+	case 'h': case 'H': case '?':
+	    help(); do_exit(OK); break;
+	case 'L':
+	    license(); do_exit(OK); break;
+	case 'm': /* undocumented, may change later */
+	    no_time = 1; break;
+	case 'M': /* undocumented, may change later */
+	    no_time = 0; break;
+	case 'n':
+	    no_name = no_time = 1; break;
+	case 'N':
+	    no_name = no_time = 0; break;
+	case 'q':
+	    quiet = 1; verbose = 0; break;
+	case 'S':
+            z_len = strlen(optarg);
+            strcpy(z_suffix, optarg);
+            break;
+	case 't':
+	    test = to_stdout = 1;
+#ifndef decompress
+	    decompress = 1;
+#endif
+	    break;
+	case 'v':
+	    verbose++; quiet = 0; break;
+	case 'V':
+	    version(); do_exit(OK); break;
+#ifdef SUPPORT_ZIP
+	case '1':  case '2':  case '3':  case '4':
+	case '5':  case '6':  case '7':  case '8':  case '9':
+	    level = optc - '0';
+	    break;
+#endif
+	default:
+	    /* Error message already emitted by getopt_long. */
+	    usage();
+	    do_exit(ERROR);
+	}
+    } /* loop on all arguments */
+
+    /* By default, save name and timestamp on compression but do not
+     * restore them on decompression.
+     */
+    if (no_time < 0) no_time = decompress;
+    if (no_name < 0) no_name = decompress;
+
+    file_count = argc - optind;
+
+    if ((z_len == 0 && !decompress) || z_len > MAX_SUFFIX) {
+        fprintf(stderr, "%s: incorrect suffix '%s'\n",
+                progname, optarg);
+        do_exit(ERROR);
+    }
+
+    /* Allocate all global buffers (for DYN_ALLOC option) */
+    ALLOC(uch, inbuf,  INBUFSIZ +INBUF_EXTRA);
+    ALLOC(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
+    ALLOC(ush, d_buf,  DIST_BUFSIZE);
+    ALLOC(uch, window, 2L*WSIZE);
+    ALLOC(ush, tab_prefix, 1L<<BITS);
+
+    /* And get to work */
+    if (file_count != 0) {
+        while (optind < argc) {
+	    treat_file(argv[optind++]);
+	}
+    } else {  /* Standard input */
+	treat_stdin();
+    }
+    do_exit(exit_code);
+    return exit_code; /* just to avoid lint warning */
+}
+
+/* ========================================================================
+ * Compress or decompress stdin
+ */
+local void treat_stdin()
+{
+    if (!force &&
+	isatty(fileno((FILE *)(decompress ? stdin : stdout)))) {
+	/* Do not send compressed data to the terminal or read it from
+	 * the terminal. We get here when user invoked the program
+	 * without parameters, so be helpful. According to the GNU standards:
+	 *
+	 *   If there is one behavior you think is most useful when the output
+	 *   is to a terminal, and another that you think is most useful when
+	 *   the output is a file or a pipe, then it is usually best to make
+	 *   the default behavior the one that is useful with output to a
+	 *   terminal, and have an option for the other behavior.
+	 *
+	 * Here we use the --force option to get the other behavior.
+	 */
+	fprintf(stderr,
+    "%s: compressed data not %s a terminal. Use -f to force %scompression.\n",
+		progname, decompress ? "read from" : "written to",
+		decompress ? "de" : "");
+	fprintf(stderr,"For help, type: %s -h\n", progname);
+	do_exit(ERROR);
+    }
+
+    strcpy(ifname, "stdin");
+    strcpy(ofname, "stdout");
+
+    /* Get the time stamp on the input file. */
+    time_stamp = 0; /* time unknown by default */
+
+    if (!no_time) {
+	if (fstat(fileno(stdin), &istat) != 0) {
+	    error("fstat(stdin)");
+	}
+	time_stamp = istat.st_mtime;
+    }
+    ifile_size = -1L; /* convention for unknown size */
+
+    clear_bufs(); /* clear input and output buffers */
+    to_stdout = 1;
+    part_nb = 0;
+
+    if (decompress) {
+	method = get_method();
+	if (method < 0) {
+	    do_exit(exit_code); /* error message already emitted */
+	}
+    }
+
+    /* Actually do the compression/decompression. Loop over zipped members.
+     */
+    for (;;) {
+	if ((*work)(fileno(stdin), fileno(stdout)) != OK) return;
+
+	if (!decompress || last_member || inptr == insize) break;
+	/* end of file */
+
+	method = get_method();
+	if (method < 0) return; /* error message already emitted */
+	bytes_out = 0;            /* required for length check */
+    }
+
+    if (verbose) {
+	if (test) {
+	    fprintf(stderr, " OK\n");
+
+	} else if (!decompress) {
+	    display_ratio(bytes_in-(bytes_out-header_bytes), bytes_in, stderr);
+	    fprintf(stderr, "\n");
+#ifdef DISPLAY_STDIN_RATIO
+	} else {
+	    display_ratio(bytes_out-(bytes_in-header_bytes), bytes_out,stderr);
+	    fprintf(stderr, "\n");
+#endif
+	}
+    }
+}
+
+/* ========================================================================
+ * Compress or decompress the given file
+ */
+local void treat_file(iname)
+    char *iname;
+{
+    /* Accept "-" as synonym for stdin */
+    if (strequ(iname, "-")) {
+	int cflag = to_stdout;
+	treat_stdin();
+	to_stdout = cflag;
+	return;
+    }
+
+    /* Check if the input file is present, set ifname and istat: */
+    if (get_istat(iname, &istat) != OK) return;
+
+    /* If the input name is that of a directory, recurse or ignore: */
+    if (S_ISDIR(istat.st_mode)) {
+	WARN((stderr,"%s: %s is a directory -- ignored\n", progname, ifname));
+	return;
+    }
+    if (!S_ISREG(istat.st_mode)) {
+	WARN((stderr,
+	      "%s: %s is not a directory or a regular file - ignored\n",
+	      progname, ifname));
+	return;
+    }
+    if (istat.st_nlink > 1 && !to_stdout && !force) {
+	WARN((stderr, "%s: %s has %d other link%c -- unchanged\n",
+	      progname, ifname,
+	      (int)istat.st_nlink - 1, istat.st_nlink > 2 ? 's' : ' '));
+	return;
+    }
+
+    ifile_size = istat.st_size;
+    time_stamp = no_time ? 0 : istat.st_mtime;
+
+    /* Generate output file name. For -r and (-t or -l), skip files
+     * without a valid gzip suffix (check done in make_ofname).
+     */
+    if (to_stdout && !test) {
+	strcpy(ofname, "stdout");
+
+    } else if (make_ofname() != OK) {
+	return;
+    }
+
+    /* Open the input file and determine compression method. The mode
+     * parameter is ignored but required by some systems (VMS) and forbidden
+     * on other systems (MacOS).
+     */
+    ifd = open(ifname, !decompress ? O_RDONLY : O_RDONLY,
+	       RW_USER);
+    if (ifd == -1) {
+	fprintf(stderr, "%s: ", progname);
+	perror(ifname);
+	exit_code = ERROR;
+	return;
+    }
+    clear_bufs(); /* clear input and output buffers */
+    part_nb = 0;
+
+    if (decompress) {
+	method = get_method(); /* updates ofname if original given */
+	if (method < 0) {
+	    close(ifd);
+	    return;               /* error message already emitted */
+	}
+    }
+
+    /* If compressing to a file, check if ofname is not ambiguous
+     * because the operating system truncates names. Otherwise, generate
+     * a new ofname and save the original name in the compressed file.
+     */
+    if (to_stdout) {
+	ofd = fileno(stdout);
+	/* keep remove_ofname as zero */
+    } else {
+	if (create_outfile() != OK) return;
+
+	if (!decompress && save_orig_name && !verbose && !quiet) {
+	    fprintf(stderr, "%s: %s compressed to %s\n",
+		    progname, ifname, ofname);
+	}
+    }
+    /* Keep the name even if not truncated except with --no-name: */
+    if (!save_orig_name) save_orig_name = !no_name;
+
+    if (verbose) {
+	fprintf(stderr, "%s:\t%s", ifname, (int)strlen(ifname) >= 15 ?
+		"" : ((int)strlen(ifname) >= 7 ? "\t" : "\t\t"));
+    }
+
+    /* Actually do the compression/decompression. Loop over zipped members.
+     */
+    for (;;) {
+	if ((*work)(ifd, ofd) != OK) {
+	    method = -1; /* force cleanup */
+	    break;
+	}
+	if (!decompress || last_member || inptr == insize) break;
+	/* end of file */
+
+	method = get_method();
+	if (method < 0) break;    /* error message already emitted */
+	bytes_out = 0;            /* required for length check */
+    }
+
+    close(ifd);
+    if (!to_stdout && close(ofd)) {
+	write_error();
+    }
+    if (method == -1) {
+	if (!to_stdout) unlink (ofname);
+	return;
+    }
+    /* Display statistics */
+    if(verbose) {
+	if (test) {
+	    fprintf(stderr, " OK");
+	} else if (decompress) {
+	    display_ratio(bytes_out-(bytes_in-header_bytes), bytes_out,stderr);
+	} else {
+	    display_ratio(bytes_in-(bytes_out-header_bytes), bytes_in, stderr);
+	}
+	if (!test && !to_stdout) {
+	    fprintf(stderr, " -- replaced with %s", ofname);
+	}
+	fprintf(stderr, "\n");
+    }
+    /* Copy modes, times, ownership, and remove the input file */
+    if (!to_stdout) {
+	copy_stat(&istat);
+    }
+}
+
+/* ========================================================================
+ * Create the output file. Return OK or ERROR.
+ * Try several times if necessary to avoid truncating the z_suffix. For
+ * example, do not create a compressed file of name "1234567890123."
+ * Sets save_orig_name to true if the file name has been truncated.
+ * IN assertions: the input file has already been open (ifd is set) and
+ *   ofname has already been updated if there was an original name.
+ * OUT assertions: ifd and ofd are closed in case of error.
+ */
+local int create_outfile()
+{
+    struct stat	ostat; /* stat for ofname */
+    int flags = O_WRONLY | O_CREAT | O_EXCL;
+
+    for (;;) {
+	/* Make sure that ofname is not an existing file */
+	if (check_ofname() != OK) {
+	    close(ifd);
+	    return ERROR;
+	}
+	/* Create the output file */
+	remove_ofname = 1;
+	ofd = open(ofname, flags, RW_USER);
+	if (ofd == -1) {
+	    perror(ofname);
+	    close(ifd);
+	    exit_code = ERROR;
+	    return ERROR;
+	}
+
+	/* Check for name truncation on new file (1234567890123.gz) */
+	if (fstat(ofd, &ostat) != 0) {
+	    fprintf(stderr, "%s: ", progname);
+	    perror(ofname);
+	    close(ifd); close(ofd);
+	    unlink(ofname);
+	    exit_code = ERROR;
+	    return ERROR;
+	}
+	if (!name_too_long(ofname, &ostat)) return OK;
+
+	if (decompress) {
+	    /* name might be too long if an original name was saved */
+	    WARN((stderr, "%s: %s: warning, name truncated\n",
+		  progname, ofname));
+	    return OK;
+	}
+	close(ofd);
+	unlink(ofname);
+	shorten_name(ofname);
+    }
+}
+
+/* ========================================================================
+ * Use lstat if available, except for -c or -f. Use stat otherwise.
+ * This allows links when not removing the original file.
+ */
+local int do_stat(name, sbuf)
+    char *name;
+    struct stat *sbuf;
+{
+    errno = 0;
+    if (!to_stdout && !force) {
+	return lstat(name, sbuf);
+    }
+    return stat(name, sbuf);
+}
+
+/* ========================================================================
+ * Return a pointer to the 'z' suffix of a file name, or NULL. For all
+ * systems, ".gz", ".z", ".Z", ".taz", ".tgz", "-gz", "-z" and "_z" are
+ * accepted suffixes, in addition to the value of the --suffix option.
+ * ".tgz" is a useful convention for tar.z files on systems limited
+ * to 3 characters extensions. On such systems, ".?z" and ".??z" are
+ * also accepted suffixes. For Unix, we do not want to accept any
+ * .??z suffix as indicating a compressed file; some people use .xyz
+ * to denote volume data.
+ *   On systems allowing multiple versions of the same file (such as VMS),
+ * this function removes any version suffix in the given name.
+ */
+local char *get_suffix(name)
+    char *name;
+{
+    int nlen, slen;
+    char suffix[MAX_SUFFIX+3]; /* last chars of name, forced to lower case */
+    static char *known_suffixes[] =
+       {z_suffix, ".gz", ".z", ".taz", ".tgz", "-gz", "-z", "_z",
+          NULL};
+    char **suf = known_suffixes;
+
+    if (strequ(z_suffix, "z")) suf++; /* check long suffixes first */
+
+    nlen = strlen(name);
+    if (nlen <= MAX_SUFFIX+2) {
+        strcpy(suffix, name);
+    } else {
+        strcpy(suffix, name+nlen-MAX_SUFFIX-2);
+    }
+    strlwr(suffix);
+    slen = strlen(suffix);
+    do {
+       int s = strlen(*suf);
+       if (slen > s && suffix[slen-s-1] != PATH_SEP
+           && strequ(suffix + slen - s, *suf)) {
+           return name+nlen-s;
+       }
+    } while (*++suf != NULL);
+
+    return NULL;
+}
+
+
+/* ========================================================================
+ * Set ifname to the input file name (with a suffix appended if necessary)
+ * and istat to its stats. For decompression, if no file exists with the
+ * original name, try adding successively z_suffix, .gz, .z, -z and .Z.
+ * For MSDOS, we try only z_suffix and z.
+ * Return OK or ERROR.
+ */
+local int get_istat(iname, sbuf)
+    char *iname;
+    struct stat *sbuf;
+{
+    int ilen;  /* strlen(ifname) */
+    static char *suffixes[] = {z_suffix, ".gz", ".z", "-z", ".Z", NULL};
+    char **suf = suffixes;
+    char *s;
+
+    strcpy(ifname, iname);
+
+    /* If input file exists, return OK. */
+    if (do_stat(ifname, sbuf) == 0) return OK;
+
+    if (!decompress || errno != ENOENT) {
+	perror(ifname);
+	exit_code = ERROR;
+	return ERROR;
+    }
+    /* file.ext doesn't exist, try adding a suffix (after removing any
+     * version number for VMS).
+     */
+    s = get_suffix(ifname);
+    if (s != NULL) {
+	perror(ifname); /* ifname already has z suffix and does not exist */
+	exit_code = ERROR;
+	return ERROR;
+    }
+    ilen = strlen(ifname);
+    if (strequ(z_suffix, ".gz")) suf++;
+
+    /* Search for all suffixes */
+    do {
+        s = *suf;
+        strcat(ifname, s);
+        if (do_stat(ifname, sbuf) == 0) return OK;
+	ifname[ilen] = '\0';
+    } while (*++suf != NULL);
+
+    /* No suffix found, complain using z_suffix: */
+    strcat(ifname, z_suffix);
+    perror(ifname);
+    exit_code = ERROR;
+    return ERROR;
+}
+
+/* ========================================================================
+ * Generate ofname given ifname. Return OK, or WARNING if file must be skipped.
+ * Sets save_orig_name to true if the file name has been truncated.
+ */
+local int make_ofname()
+{
+    char *suff;            /* ofname z suffix */
+
+    strcpy(ofname, ifname);
+    /* strip a version number if any and get the gzip suffix if present: */
+    suff = get_suffix(ofname);
+
+    if (decompress) {
+	if (suff == NULL) {
+	    /* Whith -t or -l, try all files (even without .gz suffix)
+	     * except with -r (behave as with just -dr).
+             */
+            if (test) return OK;
+
+	    /* Avoid annoying messages with -r */
+	    if (verbose || !quiet) {
+		WARN((stderr,"%s: %s: unknown suffix -- ignored\n",
+		      progname, ifname));
+	    }
+	    return WARNING;
+	}
+	/* Make a special case for .tgz and .taz: */
+	strlwr(suff);
+	if (strequ(suff, ".tgz") || strequ(suff, ".taz")) {
+	    strcpy(suff, ".tar");
+	} else {
+	    *suff = '\0'; /* strip the z suffix */
+	}
+        /* ofname might be changed later if infile contains an original name */
+
+    } else if (suff != NULL) {
+	/* Avoid annoying messages with -r (see treat_dir()) */
+	if (verbose || !quiet) {
+	    fprintf(stderr, "%s: %s already has %s suffix -- unchanged\n",
+		    progname, ifname, suff);
+	}
+	if (exit_code == OK) exit_code = WARNING;
+	return WARNING;
+    } else {
+        save_orig_name = 0;
+	strcat(ofname, z_suffix);
+
+    } /* decompress ? */
+    return OK;
+}
+
+
+/* ========================================================================
+ * Check the magic number of the input file and update ofname if an
+ * original name was given and to_stdout is not set.
+ * Return the compression method, -1 for error, -2 for warning.
+ * Set inptr to the offset of the next byte to be processed.
+ * Updates time_stamp if there is one and --no-time is not used.
+ * This function may be called repeatedly for an input file consisting
+ * of several contiguous gzip'ed members.
+ * IN assertions: there is at least one remaining compressed member.
+ *   If the member is a zip file, it must be the only one.
+ */
+local int get_method()
+{
+    uch flags;     /* compression flags */
+    char magic[2]; /* magic header */
+    ulg stamp;     /* time stamp */
+
+    /* If --force and --stdout, zcat == cat, so do not complain about
+     * premature end of file: use try_byte instead of get_byte.
+     */
+    if (force && to_stdout) {
+	magic[0] = (char)try_byte();
+	magic[1] = (char)try_byte();
+	/* If try_byte returned EOF, magic[1] == 0xff */
+    } else {
+	magic[0] = (char)get_byte();
+	magic[1] = (char)get_byte();
+    }
+    method = -1;                 /* unknown yet */
+    part_nb++;                   /* number of parts in gzip file */
+    header_bytes = 0;
+    last_member = RECORD_IO;
+    /* assume multiple members in gzip file except for record oriented I/O */
+
+    if (memcmp(magic, GZIP_MAGIC, 2) == 0
+        || memcmp(magic, OLD_GZIP_MAGIC, 2) == 0) {
+
+	method = (int)get_byte();
+	if (method != DEFLATED) {
+	    fprintf(stderr,
+		    "%s: %s: unknown method %d -- get newer version of gzip\n",
+		    progname, ifname, method);
+	    exit_code = ERROR;
+	    return -1;
+	}
+	work = unzip;
+	flags  = (uch)get_byte();
+
+	if ((flags & ENCRYPTED) != 0) {
+	    fprintf(stderr,
+		    "%s: %s is encrypted -- get newer version of gzip\n",
+		    progname, ifname);
+	    exit_code = ERROR;
+	    return -1;
+	}
+	if ((flags & CONTINUATION) != 0) {
+	    fprintf(stderr,
+	   "%s: %s is a a multi-part gzip file -- get newer version of gzip\n",
+		    progname, ifname);
+	    exit_code = ERROR;
+	    if (force <= 1) return -1;
+	}
+	if ((flags & RESERVED) != 0) {
+	    fprintf(stderr,
+		    "%s: %s has flags 0x%x -- get newer version of gzip\n",
+		    progname, ifname, flags);
+	    exit_code = ERROR;
+	    if (force <= 1) return -1;
+	}
+	stamp  = (ulg)get_byte();
+	stamp |= ((ulg)get_byte()) << 8;
+	stamp |= ((ulg)get_byte()) << 16;
+	stamp |= ((ulg)get_byte()) << 24;
+	if (stamp != 0 && !no_time) time_stamp = stamp;
+
+	(void)get_byte();  /* Ignore extra flags for the moment */
+	(void)get_byte();  /* Ignore OS type for the moment */
+
+	if ((flags & CONTINUATION) != 0) {
+	    unsigned part = (unsigned)get_byte();
+	    part |= ((unsigned)get_byte())<<8;
+	    if (verbose) {
+		fprintf(stderr,"%s: %s: part number %u\n",
+			progname, ifname, part);
+	    }
+	}
+	if ((flags & EXTRA_FIELD) != 0) {
+	    unsigned len = (unsigned)get_byte();
+	    len |= ((unsigned)get_byte())<<8;
+	    if (verbose) {
+		fprintf(stderr,"%s: %s: extra field of %u bytes ignored\n",
+			progname, ifname, len);
+	    }
+	    while (len--) (void)get_byte();
+	}
+
+	/* Get original file name if it was truncated */
+	if ((flags & ORIG_NAME) != 0) {
+	    if (no_name || to_stdout || part_nb > 1) {
+		/* Discard the old name */
+		char c; /* dummy used for NeXTstep 3.0 cc optimizer bug */
+		do {c=get_byte();} while (c != 0);
+	    } else {
+		/* Copy the base name. Keep a directory prefix intact. */
+                char *p = basename(ofname);
+		for (;;) {
+		    *p = (char)get_char();
+		    if (*p++ == '\0') break;
+		    if (p >= ofname+sizeof(ofname)) {
+			error("corrupted input -- file name too large");
+		    }
+		}
+	    } /* no_name || to_stdout */
+	} /* ORIG_NAME */
+
+	/* Discard file comment if any */
+	if ((flags & COMMENT) != 0) {
+	    while (get_char() != 0) /* null */ ;
+	}
+	if (part_nb == 1) {
+	    header_bytes = inptr + 2*sizeof(long); /* include crc and size */
+	}
+    } else if (force && to_stdout) { /* pass input unchanged */
+	method = STORED;
+	work = copy;
+        inptr = 0;
+	last_member = 1;
+    }
+    if (method >= 0) return method;
+
+    if (part_nb == 1) {
+	fprintf(stderr, "\n%s: %s: not in gzip format\n", progname, ifname);
+	exit_code = ERROR;
+	return -1;
+    } else {
+	WARN((stderr, "\n%s: %s: decompression OK, trailing garbage ignored\n",
+	      progname, ifname));
+	return -2;
+    }
+}
+
+
+/* ========================================================================
+ * Return true if the two stat structures correspond to the same file.
+ */
+local int same_file(stat1, stat2)
+    struct stat *stat1;
+    struct stat *stat2;
+{
+    return stat1->st_ino   == stat2->st_ino
+	&& stat1->st_dev   == stat2->st_dev
+#ifdef NO_ST_INO
+        /* Can't rely on st_ino and st_dev, use other fields: */
+	&& stat1->st_mode  == stat2->st_mode
+	&& stat1->st_uid   == stat2->st_uid
+	&& stat1->st_gid   == stat2->st_gid
+	&& stat1->st_size  == stat2->st_size
+	&& stat1->st_atime == stat2->st_atime
+	&& stat1->st_mtime == stat2->st_mtime
+	&& stat1->st_ctime == stat2->st_ctime
+#endif
+	    ;
+}
+
+/* ========================================================================
+ * Return true if a file name is ambiguous because the operating system
+ * truncates file names.
+ */
+local int name_too_long(name, statb)
+    char *name;           /* file name to check */
+    struct stat *statb;   /* stat buf for this file name */
+{
+    int s = strlen(name);
+    char c = name[s-1];
+    struct stat	tstat; /* stat for truncated name */
+    int res;
+
+    tstat = *statb;      /* Just in case OS does not fill all fields */
+    name[s-1] = '\0';
+    res = stat(name, &tstat) == 0 && same_file(statb, &tstat);
+    name[s-1] = c;
+    Trace((stderr, " too_long(%s) => %d\n", name, res));
+    return res;
+}
+
+/* ========================================================================
+ * Shorten the given name by one character, or replace a .tar extension
+ * with .tgz. Truncate the last part of the name which is longer than
+ * MIN_PART characters: 1234.678.012.gz -> 123.678.012.gz. If the name
+ * has only parts shorter than MIN_PART truncate the longest part.
+ * For decompression, just remove the last character of the name.
+ *
+ * IN assertion: for compression, the suffix of the given name is z_suffix.
+ */
+local void shorten_name(name)
+    char *name;
+{
+    int len;                 /* length of name without z_suffix */
+    char *trunc = NULL;      /* character to be truncated */
+    int plen;                /* current part length */
+    int min_part = MIN_PART; /* current minimum part length */
+    char *p;
+
+    len = strlen(name);
+    if (decompress) {
+	if (len <= 1) error("name too short");
+	name[len-1] = '\0';
+	return;
+    }
+    p = get_suffix(name);
+    if (p == NULL) error("can't recover suffix\n");
+    *p = '\0';
+    save_orig_name = 1;
+
+    /* compress 1234567890.tar to 1234567890.tgz */
+    if (len > 4 && strequ(p-4, ".tar")) {
+	strcpy(p-4, ".tgz");
+	return;
+    }
+    /* Try keeping short extensions intact:
+     * 1234.678.012.gz -> 123.678.012.gz
+     */
+    do {
+	p = strrchr(name, PATH_SEP);
+	p = p ? p+1 : name;
+	while (*p) {
+	    plen = strcspn(p, ".");
+	    p += plen;
+	    if (plen > min_part) trunc = p-1;
+	    if (*p) p++;
+	}
+    } while (trunc == NULL && --min_part != 0);
+
+    if (trunc != NULL) {
+	do {
+	    trunc[0] = trunc[1];
+	} while (*trunc++);
+	trunc--;
+    } else {
+	trunc = strrchr(name, '.');
+	if (trunc == NULL) error("internal error in shorten_name");
+	if (trunc[1] == '\0') trunc--; /* force truncation */
+    }
+    strcpy(trunc, z_suffix);
+}
+
+/* ========================================================================
+ * If compressing to a file, check if ofname is not ambiguous
+ * because the operating system truncates names. Otherwise, generate
+ * a new ofname and save the original name in the compressed file.
+ * If the compressed file already exists, ask for confirmation.
+ *    The check for name truncation is made dynamically, because different
+ * file systems on the same OS might use different truncation rules (on SVR4
+ * s5 truncates to 14 chars and ufs does not truncate).
+ *    This function returns -1 if the file must be skipped, and
+ * updates save_orig_name if necessary.
+ * IN assertions: save_orig_name is already set if ofname has been
+ * already truncated because of NO_MULTIPLE_DOTS. The input file has
+ * already been open and istat is set.
+ */
+local int check_ofname()
+{
+    struct stat	ostat; /* stat for ofname */
+
+#ifdef ENAMETOOLONG
+    /* Check for strictly conforming Posix systems (which return ENAMETOOLONG
+     * instead of silently truncating filenames).
+     */
+    errno = 0;
+    while (stat(ofname, &ostat) != 0) {
+        if (errno != ENAMETOOLONG) return 0; /* ofname does not exist */
+	shorten_name(ofname);
+    }
+#else
+    if (stat(ofname, &ostat) != 0) return 0;
+#endif
+    /* Check for name truncation on existing file. Do this even on systems
+     * defining ENAMETOOLONG, because on most systems the strict Posix
+     * behavior is disabled by default (silent name truncation allowed).
+     */
+    if (!decompress && name_too_long(ofname, &ostat)) {
+	shorten_name(ofname);
+	if (stat(ofname, &ostat) != 0) return 0;
+    }
+
+    /* Check that the input and output files are different (could be
+     * the same by name truncation or links).
+     */
+    if (same_file(&istat, &ostat)) {
+	if (strequ(ifname, ofname)) {
+	    fprintf(stderr, "%s: %s: cannot %scompress onto itself\n",
+		    progname, ifname, decompress ? "de" : "");
+	} else {
+	    fprintf(stderr, "%s: %s and %s are the same file\n",
+		    progname, ifname, ofname);
+	}
+	exit_code = ERROR;
+	return ERROR;
+    }
+    /* Ask permission to overwrite the existing file */
+    if (!force) {
+#if 0
+	char response[80];
+	strcpy(response,"n");
+	fprintf(stderr, "%s: %s already exists;", progname, ofname);
+	if (foreground && isatty(fileno(stdin))) {
+	    fprintf(stderr, " do you wish to overwrite (y or n)? ");
+	    (void)fgets(response, sizeof(response)-1, stdin);
+	}
+	if (tolow(*response) != 'y') {
+	    fprintf(stderr, "\tnot overwritten\n");
+#endif
+	    if (exit_code == OK) exit_code = WARNING;
+	    return ERROR;
+#if 0
+	}
+#endif
+    }
+    (void) chmod(ofname, 0777);
+    if (unlink(ofname)) {
+	fprintf(stderr, "%s: ", progname);
+	perror(ofname);
+	exit_code = ERROR;
+	return ERROR;
+    }
+    return OK;
+}
+
+
+/* ========================================================================
+ * Set the access and modification times from the given stat buffer.
+ */
+local void reset_times (name, statb)
+    char *name;
+    struct stat *statb;
+{
+    struct utimbuf	timep;
+
+    /* Copy the time stamp */
+    timep.actime  = statb->st_atime;
+    timep.modtime = statb->st_mtime;
+
+    /* Some systems (at least OS/2) do not support utime on directories */
+    if (utime(name, &timep) && !S_ISDIR(statb->st_mode)) {
+	WARN((stderr, "%s: ", progname));
+	if (!quiet) perror(ofname);
+    }
+}
+
+
+/* ========================================================================
+ * Copy modes, times, ownership from input file to output file.
+ * IN assertion: to_stdout is false.
+ */
+local void copy_stat(ifstat)
+    struct stat *ifstat;
+{
+    if (decompress && time_stamp != 0 && ifstat->st_mtime != time_stamp) {
+	ifstat->st_mtime = time_stamp;
+	if (verbose > 1) {
+	    fprintf(stderr, "%s: time stamp restored\n", ofname);
+	}
+    }
+    reset_times(ofname, ifstat);
+
+    /* Copy the protection modes */
+    if (chmod(ofname, ifstat->st_mode & 07777)) {
+	WARN((stderr, "%s: ", progname));
+	if (!quiet) perror(ofname);
+    }
+
+    chown(ofname, ifstat->st_uid, ifstat->st_gid);  /* Copy ownership */
+
+    remove_ofname = 0;
+    /* It's now safe to remove the input file: */
+    (void) chmod(ifname, 0777);
+    if (unlink(ifname)) {
+	WARN((stderr, "%s: ", progname));
+	if (!quiet) perror(ifname);
+    }
+}
+
+/* ========================================================================
+ * Free all dynamically allocated variables and exit with the given code.
+ */
+local void do_exit(exitcode)
+    int exitcode;
+{
+    static int in_exit = 0;
+
+    if (in_exit) exit(exitcode);
+    in_exit = 1;
+    if (env != NULL)  free(env),  env  = NULL;
+    if (args != NULL) free((char*)args), args = NULL;
+    FREE(inbuf);
+    FREE(outbuf);
+    FREE(d_buf);
+    FREE(window);
+    FREE(tab_prefix);
+    exit(exitcode);
+}
+
+/* ========================================================================
+ * Signal and error handler.
+ */
+void abort_gzip()
+{
+   if (remove_ofname) {
+       close(ofd);
+       unlink (ofname);
+   }
+   do_exit(ERROR);
+}
diff --git a/usr/gzip/gzip.h b/usr/gzip/gzip.h
new file mode 100644
index 0000000..7cd2fbd
--- /dev/null
+++ b/usr/gzip/gzip.h
@@ -0,0 +1,298 @@
+/* gzip.h -- common declarations for all gzip modules
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#if defined(__STDC__) || defined(PROTO)
+#  define OF(args)  args
+#else
+#  define OF(args)  ()
+#endif
+
+#ifdef __STDC__
+   typedef void *voidp;
+#else
+   typedef char *voidp;
+#endif
+
+/* I don't like nested includes, but the string and io functions are used
+ * too often
+ */
+#include <stdio.h>
+#include <string.h>
+#define memzero(s, n)     memset ((voidp)(s), 0, (n))
+
+#define local static
+
+typedef unsigned char  uch;
+typedef unsigned short ush;
+typedef unsigned long  ulg;
+
+/* Return codes from gzip */
+#define OK      0
+#define ERROR   1
+#define WARNING 2
+
+/* Compression methods (see algorithm.doc) */
+#define STORED      0
+#define COMPRESSED  1
+#define PACKED      2
+#define LZHED       3
+/* methods 4 to 7 reserved */
+#define DEFLATED    8
+#define MAX_METHODS 9
+extern int method;         /* compression method */
+
+/* To save memory for 16 bit systems, some arrays are overlaid between
+ * the various modules:
+ * deflate:  prev+head   window      d_buf  l_buf  outbuf
+ * unlzw:    tab_prefix  tab_suffix  stack  inbuf  outbuf
+ * inflate:              window             inbuf
+ * unpack:               window             inbuf  prefix_len
+ * unlzh:    left+right  window      c_table inbuf c_len
+ * For compression, input is done in window[]. For decompression, output
+ * is done in window except for unlzw.
+ */
+
+#ifndef	INBUFSIZ
+#  ifdef SMALL_MEM
+#    define INBUFSIZ  0x2000  /* input buffer size */
+#  else
+#    define INBUFSIZ  0x8000  /* input buffer size */
+#  endif
+#endif
+#define INBUF_EXTRA  64     /* required by unlzw() */
+
+#ifndef	OUTBUFSIZ
+#  ifdef SMALL_MEM
+#    define OUTBUFSIZ   8192  /* output buffer size */
+#  else
+#    define OUTBUFSIZ  16384  /* output buffer size */
+#  endif
+#endif
+#define OUTBUF_EXTRA 2048   /* required by unlzw() */
+
+#ifndef DIST_BUFSIZE
+#  ifdef SMALL_MEM
+#    define DIST_BUFSIZE 0x2000 /* buffer for distances, see trees.c */
+#  else
+#    define DIST_BUFSIZE 0x8000 /* buffer for distances, see trees.c */
+#  endif
+#endif
+
+#ifdef DYN_ALLOC
+#  define EXTERN(type, array)  extern type * near array
+#  define DECLARE(type, array, size)  type * near array
+#  define ALLOC(type, array, size) { \
+      array = (type*)fcalloc((size_t)(((size)+1L)/2), 2*sizeof(type)); \
+      if (array == NULL) error("insufficient memory"); \
+   }
+#  define FREE(array) {if (array != NULL) fcfree(array), array=NULL;}
+#else
+#  define EXTERN(type, array)  extern type array[]
+#  define DECLARE(type, array, size)  type array[size]
+#  define ALLOC(type, array, size)
+#  define FREE(array)
+#endif
+
+EXTERN(uch, inbuf);          /* input buffer */
+EXTERN(uch, outbuf);         /* output buffer */
+EXTERN(ush, d_buf);          /* buffer for distances, see trees.c */
+EXTERN(uch, window);         /* Sliding window and suffix table (unlzw) */
+#define tab_suffix window
+#ifndef MAXSEG_64K
+#  define tab_prefix prev    /* hash link (see deflate.c) */
+#  define head (prev+WSIZE)  /* hash head (see deflate.c) */
+   EXTERN(ush, tab_prefix);  /* prefix code (see unlzw.c) */
+#else
+#  define tab_prefix0 prev
+#  define head tab_prefix1
+   EXTERN(ush, tab_prefix0); /* prefix for even codes */
+   EXTERN(ush, tab_prefix1); /* prefix for odd  codes */
+#endif
+
+extern unsigned insize; /* valid bytes in inbuf */
+extern unsigned inptr;  /* index of next byte to be processed in inbuf */
+extern unsigned outcnt; /* bytes in output buffer */
+
+extern long bytes_in;   /* number of input bytes */
+extern long bytes_out;  /* number of output bytes */
+extern long header_bytes;/* number of bytes in gzip header */
+
+#define isize bytes_in
+/* for compatibility with old zip sources (to be cleaned) */
+
+extern int  ifd;        /* input file descriptor */
+extern int  ofd;        /* output file descriptor */
+extern char ifname[];   /* input file name or "stdin" */
+extern char ofname[];   /* output file name or "stdout" */
+extern char *progname;  /* program name */
+
+extern time_t time_stamp; /* original time stamp (modification time) */
+extern long ifile_size; /* input file size, -1 for devices (debug only) */
+
+typedef int file_t;     /* Do not use stdio */
+#define NO_FILE  (-1)   /* in memory compression */
+
+
+#define	PACK_MAGIC     "\037\036" /* Magic header for packed files */
+#define	GZIP_MAGIC     "\037\213" /* Magic header for gzip files, 1F 8B */
+#define	OLD_GZIP_MAGIC "\037\236" /* Magic header for gzip 0.5 = freeze 1.x */
+#define	LZH_MAGIC      "\037\240" /* Magic header for SCO LZH Compress files*/
+#define PKZIP_MAGIC    "\120\113\003\004" /* Magic header for pkzip files */
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
+#define RESERVED     0xC0 /* bit 6,7:   reserved */
+
+/* internal file attribute */
+#define UNKNOWN 0xffff
+#define BINARY  0
+#define ASCII   1
+
+#ifndef WSIZE
+#  define WSIZE 0x8000     /* window size--must be a power of two, and */
+#endif                     /*  at least 32K for zip's deflate method */
+
+#define MIN_MATCH  3
+#define MAX_MATCH  258
+/* The minimum and maximum match lengths */
+
+#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
+/* Minimum amount of lookahead, except at the end of the input file.
+ * See deflate.c for comments about the MIN_MATCH+1.
+ */
+
+#define MAX_DIST  (WSIZE-MIN_LOOKAHEAD)
+/* In order to simplify the code, particularly on 16 bit machines, match
+ * distances are limited to MAX_DIST instead of WSIZE.
+ */
+
+extern int decrypt;        /* flag to turn on decryption */
+extern int exit_code;      /* program exit code */
+extern int verbose;        /* be verbose (-v) */
+extern int quiet;          /* be quiet (-q) */
+extern int level;          /* compression level */
+extern int test;           /* check .z file integrity */
+extern int to_stdout;      /* output to stdout (-c) */
+extern int save_orig_name; /* set if original name must be saved */
+
+#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf(0))
+#define try_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf(1))
+
+/* put_byte is used for the compressed output, put_ubyte for the
+ * uncompressed output. However unlzw() uses window for its
+ * suffix table instead of its output buffer, so it does not use put_ubyte
+ * (to be cleaned up).
+ */
+#define put_byte(c) {outbuf[outcnt++]=(uch)(c); if (outcnt==OUTBUFSIZ)\
+   flush_outbuf();}
+#define put_ubyte(c) {window[outcnt++]=(uch)(c); if (outcnt==WSIZE)\
+   flush_window();}
+
+/* Output a 16 bit value, lsb first */
+#define put_short(w) \
+{ if (outcnt < OUTBUFSIZ-2) { \
+    outbuf[outcnt++] = (uch) ((w) & 0xff); \
+    outbuf[outcnt++] = (uch) ((ush)(w) >> 8); \
+  } else { \
+    put_byte((uch)((w) & 0xff)); \
+    put_byte((uch)((ush)(w) >> 8)); \
+  } \
+}
+
+/* Output a 32 bit value to the bit stream, lsb first */
+#define put_long(n) { \
+    put_short((n) & 0xffff); \
+    put_short(((ulg)(n)) >> 16); \
+}
+
+#define seekable()    0  /* force sequential output */
+#define translate_eol 0  /* no option -a yet */
+
+#define tolow(c)  (isupper(c) ? (c)-'A'+'a' : (c))    /* force to lower case */
+
+/* Macros for getting two-byte and four-byte header values */
+#define SH(p) ((ush)(uch)((p)[0]) | ((ush)(uch)((p)[1]) << 8))
+#define LG(p) ((ulg)(SH(p)) | ((ulg)(SH((p)+2)) << 16))
+
+/* Diagnostic functions */
+#ifdef DEBUG
+#  define Assert(cond,msg) {if(!(cond)) error(msg);}
+#  define Trace(x) fprintf x
+#  define Tracev(x) {if (verbose) fprintf x ;}
+#  define Tracevv(x) {if (verbose>1) fprintf x ;}
+#  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
+#  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
+#else
+#  define Assert(cond,msg)
+#  define Trace(x)
+#  define Tracev(x)
+#  define Tracevv(x)
+#  define Tracec(c,x)
+#  define Tracecv(c,x)
+#endif
+
+#define WARN(msg) {if (!quiet) fprintf msg ; \
+		   if (exit_code == OK) exit_code = WARNING;}
+
+	/* in zip.c: */
+extern int zip        OF((int in, int out));
+extern int file_read  OF((char *buf,  unsigned size));
+
+	/* in unzip.c */
+extern int unzip      OF((int in, int out));
+extern int check_zipfile OF((int in));
+
+	/* in gzip.c */
+void abort_gzip OF((void));
+
+        /* in deflate.c */
+void lm_init OF((int pack_level, ush *flags));
+ulg  deflate OF((void));
+
+        /* in trees.c */
+void ct_init     OF((ush *attr, int *method));
+int  ct_tally    OF((int dist, int lc));
+ulg  flush_block OF((char *buf, ulg stored_len, int eof));
+
+        /* in bits.c */
+void     bi_init    OF((file_t zipfile));
+void     send_bits  OF((int value, int length));
+unsigned bi_reverse OF((unsigned value, int length));
+void     bi_windup  OF((void));
+void     copy_block OF((char *buf, unsigned len, int header));
+extern   int (*read_buf) OF((char *buf, unsigned size));
+
+	/* in util.c: */
+extern int copy           OF((int in, int out));
+extern ulg  updcrc        OF((uch *s, unsigned n));
+extern void clear_bufs    OF((void));
+extern int  fill_inbuf    OF((int eof_ok));
+extern void flush_outbuf  OF((void));
+extern void flush_window  OF((void));
+extern void write_buf     OF((int fd, voidp buf, unsigned cnt));
+extern char *strlwr       OF((char *s));
+extern char *basename     OF((char *fname));
+extern void make_simple_name OF((char *name));
+extern char *add_envopt   OF((int *argcp, char ***argvp, char *env));
+extern void error         OF((char *m));
+extern void warn          OF((char *a, char *b));
+extern void read_error    OF((void));
+extern void write_error   OF((void));
+extern void display_ratio OF((long num, long den, FILE *file));
+extern voidp xmalloc      OF((unsigned int size));
+
+	/* in inflate.c */
+extern int inflate OF((void));
+
+/* stuff from lzw.h */
+#ifndef BITS
+#  define BITS 16
+#endif
diff --git a/usr/gzip/inflate.c b/usr/gzip/inflate.c
new file mode 100644
index 0000000..a540538
--- /dev/null
+++ b/usr/gzip/inflate.c
@@ -0,0 +1,950 @@
+/* inflate.c -- Not copyrighted 1992 by Mark Adler
+   version c10p1, 10 January 1993 */
+
+/* You can do whatever you like with this source file, though I would
+   prefer that if you modify it and redistribute it that you include
+   comments to that effect with your name and the date.  Thank you.
+   [The history has been moved to the file ChangeLog.]
+ */
+
+/*
+   Inflate deflated (PKZIP's method 8 compressed) data.  The compression
+   method searches for as much of the current string of bytes (up to a
+   length of 258) in the previous 32K bytes.  If it doesn't find any
+   matches (of at least length 3), it codes the next byte.  Otherwise, it
+   codes the length of the matched string and its distance backwards from
+   the current position.  There is a single Huffman code that codes both
+   single bytes (called "literals") and match lengths.  A second Huffman
+   code codes the distance information, which follows a length code.  Each
+   length or distance code actually represents a base value and a number
+   of "extra" (sometimes zero) bits to get to add to the base value.  At
+   the end of each deflated block is a special end-of-block (EOB) literal/
+   length code.  The decoding process is basically: get a literal/length
+   code; if EOB then done; if a literal, emit the decoded byte; if a
+   length then get the distance and emit the referred-to bytes from the
+   sliding window of previously emitted data.
+
+   There are (currently) three kinds of inflate blocks: stored, fixed, and
+   dynamic.  The compressor deals with some chunk of data at a time, and
+   decides which method to use on a chunk-by-chunk basis.  A chunk might
+   typically be 32K or 64K.  If the chunk is uncompressible, then the
+   "stored" method is used.  In this case, the bytes are simply stored as
+   is, eight bits per byte, with none of the above coding.  The bytes are
+   preceded by a count, since there is no longer an EOB code.
+
+   If the data is compressible, then either the fixed or dynamic methods
+   are used.  In the dynamic method, the compressed data is preceded by
+   an encoding of the literal/length and distance Huffman codes that are
+   to be used to decode this block.  The representation is itself Huffman
+   coded, and so is preceded by a description of that code.  These code
+   descriptions take up a little space, and so for small blocks, there is
+   a predefined set of codes, called the fixed codes.  The fixed method is
+   used if the block codes up smaller that way (usually for quite small
+   chunks), otherwise the dynamic method is used.  In the latter case, the
+   codes are customized to the probabilities in the current block, and so
+   can code it much better than the pre-determined fixed codes.
+
+   The Huffman codes themselves are decoded using a mutli-level table
+   lookup, in order to maximize the speed of decoding plus the speed of
+   building the decoding tables.  See the comments below that precede the
+   lbits and dbits tuning parameters.
+ */
+
+
+/*
+   Notes beyond the 1.93a appnote.txt:
+
+   1. Distance pointers never point before the beginning of the output
+      stream.
+   2. Distance pointers can point back across blocks, up to 32k away.
+   3. There is an implied maximum of 7 bits for the bit length table and
+      15 bits for the actual data.
+   4. If only one code exists, then it is encoded using one bit.  (Zero
+      would be more efficient, but perhaps a little confusing.)  If two
+      codes exist, they are coded using one bit each (0 and 1).
+   5. There is no way of sending zero distance codes--a dummy must be
+      sent if there are none.  (History: a pre 2.0 version of PKZIP would
+      store blocks with no distance codes, but this was discovered to be
+      too harsh a criterion.)  Valid only for 1.93a.  2.04c does allow
+      zero distance codes, which is sent as one code of zero bits in
+      length.
+   6. There are up to 286 literal/length codes.  Code 256 represents the
+      end-of-block.  Note however that the static length tree defines
+      288 codes just to fill out the Huffman codes.  Codes 286 and 287
+      cannot be used though, since there is no length base or extra bits
+      defined for them.  Similarly, there are up to 30 distance codes.
+      However, static trees define 32 codes (all 5 bits) to fill out the
+      Huffman codes, but the last two had better not show up in the data.
+   7. Unzip can check dynamic Huffman blocks for complete code sets.
+      The exception is that a single code would not be complete (see #4).
+   8. The five bits following the block type is really the number of
+      literal codes sent minus 257.
+   9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
+      (1+6+6).  Therefore, to output three times the length, you output
+      three codes (1+1+1), whereas to output four times the same length,
+      you only need two codes (1+3).  Hmm.
+  10. In the tree reconstruction algorithm, Code = Code + Increment
+      only if BitLength(i) is not zero.  (Pretty obvious.)
+  11. Correction: 4 Bits: # of Bit Length codes - 4     (4 - 19)
+  12. Note: length code 284 can represent 227-258, but length code 285
+      really is 258.  The last length deserves its own, short code
+      since it gets used a lot in very redundant files.  The length
+      258 is special since 258 - 3 (the min match length) is 255.
+  13. The literal/length and distance code bit lengths are read as a
+      single stream of lengths.  It is possible (and advantageous) for
+      a repeat code (16, 17, or 18) to go across the boundary between
+      the two sets of lengths.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: inflate.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+#include <sys/types.h>
+#include <stdlib.h>
+
+#include "tailor.h"
+#include "gzip.h"
+#define slide window
+
+/* Huffman code lookup table entry--this entry is four bytes for machines
+   that have 16-bit pointers (e.g. PC's in the small or medium model).
+   Valid extra bits are 0..13.  e == 15 is EOB (end of block), e == 16
+   means that v is a literal, 16 < e < 32 means that v is a pointer to
+   the next table, which codes e - 16 bits, and lastly e == 99 indicates
+   an unused code.  If a code with e == 99 is looked up, this implies an
+   error in the data. */
+struct huft {
+  uch e;                /* number of extra bits or operation */
+  uch b;                /* number of bits in this code or subcode */
+  union {
+    ush n;              /* literal, length base, or distance base */
+    struct huft *t;     /* pointer to next level of table */
+  } v;
+};
+
+
+/* Function prototypes */
+int huft_build OF((unsigned *, unsigned, unsigned, ush *, ush *,
+                   struct huft **, int *));
+int huft_free OF((struct huft *));
+int inflate_codes OF((struct huft *, struct huft *, int, int));
+int inflate_stored OF((void));
+int inflate_fixed OF((void));
+int inflate_dynamic OF((void));
+int inflate_block OF((int *));
+int inflate OF((void));
+
+
+/* The inflate algorithm uses a sliding 32K byte window on the uncompressed
+   stream to find repeated byte strings.  This is implemented here as a
+   circular buffer.  The index is updated simply by incrementing and then
+   and'ing with 0x7fff (32K-1). */
+/* It is left to other modules to supply the 32K area.  It is assumed
+   to be usable as if it were declared "uch slide[32768];" or as just
+   "uch *slide;" and then malloc'ed in the latter case.  The definition
+   must be in unzip.h, included above. */
+/* unsigned wp;             current position in slide */
+#define wp outcnt
+#define flush_output(w) (wp=(w),flush_window())
+
+/* Tables for deflate from PKZIP's appnote.txt. */
+static unsigned border[] = {    /* Order of the bit length code lengths */
+        16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+static ush cplens[] = {         /* Copy lengths for literal codes 257..285 */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
+        /* note: see note #13 above about the 258 in this list. */
+static ush cplext[] = {         /* Extra bits for literal codes 257..285 */
+        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
+static ush cpdist[] = {         /* Copy offsets for distance codes 0..29 */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+        8193, 12289, 16385, 24577};
+static ush cpdext[] = {         /* Extra bits for distance codes */
+        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+        12, 12, 13, 13};
+
+
+
+/* Macros for inflate() bit peeking and grabbing.
+   The usage is:
+
+        NEEDBITS(j)
+        x = b & mask_bits[j];
+        DUMPBITS(j)
+
+   where NEEDBITS makes sure that b has at least j bits in it, and
+   DUMPBITS removes the bits from b.  The macros use the variable k
+   for the number of bits in b.  Normally, b and k are register
+   variables for speed, and are initialized at the beginning of a
+   routine that uses these macros from a global bit buffer and count.
+
+   If we assume that EOB will be the longest code, then we will never
+   ask for bits with NEEDBITS that are beyond the end of the stream.
+   So, NEEDBITS should not read any more bytes than are needed to
+   meet the request.  Then no bytes need to be "returned" to the buffer
+   at the end of the last block.
+
+   However, this assumption is not true for fixed blocks--the EOB code
+   is 7 bits, but the other literal/length codes can be 8 or 9 bits.
+   (The EOB code is shorter than other codes because fixed blocks are
+   generally short.  So, while a block always has an EOB, many other
+   literal/length codes have a significantly lower probability of
+   showing up at all.)  However, by making the first table have a
+   lookup of seven bits, the EOB code will be found in that first
+   lookup, and so will not require that too many bits be pulled from
+   the stream.
+ */
+
+ulg bb;                         /* bit buffer */
+unsigned bk;                    /* bits in bit buffer */
+
+ush mask_bits[] = {
+    0x0000,
+    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
+    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
+};
+
+#ifdef CRYPT
+  uch cc;
+#  define NEXTBYTE() \
+     (decrypt ? (cc = get_byte(), cc) : get_byte())
+#else
+#  define NEXTBYTE()  (uch)get_byte()
+#endif
+#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
+#define DUMPBITS(n) {b>>=(n);k-=(n);}
+
+
+/*
+   Huffman code decoding is performed using a multi-level table lookup.
+   The fastest way to decode is to simply build a lookup table whose
+   size is determined by the longest code.  However, the time it takes
+   to build this table can also be a factor if the data being decoded
+   is not very long.  The most common codes are necessarily the
+   shortest codes, so those codes dominate the decoding time, and hence
+   the speed.  The idea is you can have a shorter table that decodes the
+   shorter, more probable codes, and then point to subsidiary tables for
+   the longer codes.  The time it costs to decode the longer codes is
+   then traded against the time it takes to make longer tables.
+
+   This results of this trade are in the variables lbits and dbits
+   below.  lbits is the number of bits the first level table for literal/
+   length codes can decode in one step, and dbits is the same thing for
+   the distance codes.  Subsequent tables are also less than or equal to
+   those sizes.  These values may be adjusted either when all of the
+   codes are shorter than that, in which case the longest code length in
+   bits is used, or when the shortest code is *longer* than the requested
+   table size, in which case the length of the shortest code in bits is
+   used.
+
+   There are two different values for the two tables, since they code a
+   different number of possibilities each.  The literal/length table
+   codes 286 possible values, or in a flat code, a little over eight
+   bits.  The distance table codes 30 possible values, or a little less
+   than five bits, flat.  The optimum values for speed end up being
+   about one bit more than those, so lbits is 8+1 and dbits is 5+1.
+   The optimum values may differ though from machine to machine, and
+   possibly even between compilers.  Your mileage may vary.
+ */
+
+
+int lbits = 9;          /* bits in base literal/length lookup table */
+int dbits = 6;          /* bits in base distance lookup table */
+
+
+/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
+#define BMAX 16         /* maximum bit length of any code (16 for explode) */
+#define N_MAX 288       /* maximum number of codes in any set */
+
+
+unsigned hufts;         /* track memory usage */
+
+
+int huft_build(b, n, s, d, e, t, m)
+unsigned *b;            /* code lengths in bits (all assumed <= BMAX) */
+unsigned n;             /* number of codes (assumed <= N_MAX) */
+unsigned s;             /* number of simple-valued codes (0..s-1) */
+ush *d;                 /* list of base values for non-simple codes */
+ush *e;                 /* list of extra bits for non-simple codes */
+struct huft **t;        /* result: starting table */
+int *m;                 /* maximum lookup bits, returns actual */
+/* Given a list of code lengths and a maximum table size, make a set of
+   tables to decode that set of codes.  Return zero on success, one if
+   the given code set is incomplete (the tables are still built in this
+   case), two if the input is invalid (all zero length codes or an
+   oversubscribed set of lengths), and three if not enough memory. */
+{
+  unsigned a;                   /* counter for codes of length k */
+  unsigned c[BMAX+1];           /* bit length count table */
+  unsigned f;                   /* i repeats in table every f entries */
+  int g;                        /* maximum code length */
+  int h;                        /* table level */
+  register unsigned i;          /* counter, current code */
+  register unsigned j;          /* counter */
+  register int k;               /* number of bits in current code */
+  int l;                        /* bits per table (returned in m) */
+  register unsigned *p;         /* pointer into c[], b[], or v[] */
+  register struct huft *q;      /* points to current table */
+  struct huft r;                /* table entry for structure assignment */
+  struct huft *u[BMAX];         /* table stack */
+  unsigned v[N_MAX];            /* values in order of bit length */
+  register int w;               /* bits before this table == (l * h) */
+  unsigned x[BMAX+1];           /* bit offsets, then code stack */
+  unsigned *xp;                 /* pointer into x */
+  int y;                        /* number of dummy codes added */
+  unsigned z;                   /* number of entries in current table */
+
+
+  /* Generate counts for each bit length */
+  memzero(c, sizeof(c));
+  p = b;  i = n;
+  do {
+    Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"),
+	    n-i, *p));
+    c[*p]++;                    /* assume all entries <= BMAX */
+    p++;                      /* Can't combine with above line (Solaris bug) */
+  } while (--i);
+  if (c[0] == n)                /* null input--all zero length codes */
+  {
+    *t = (struct huft *)NULL;
+    *m = 0;
+    return 0;
+  }
+
+
+  /* Find minimum and maximum length, bound *m by those */
+  l = *m;
+  for (j = 1; j <= BMAX; j++)
+    if (c[j])
+      break;
+  k = j;                        /* minimum code length */
+  if ((unsigned)l < j)
+    l = j;
+  for (i = BMAX; i; i--)
+    if (c[i])
+      break;
+  g = i;                        /* maximum code length */
+  if ((unsigned)l > i)
+    l = i;
+  *m = l;
+
+
+  /* Adjust last length count to fill out codes, if needed */
+  for (y = 1 << j; j < i; j++, y <<= 1)
+    if ((y -= c[j]) < 0)
+      return 2;                 /* bad input: more codes than bits */
+  if ((y -= c[i]) < 0)
+    return 2;
+  c[i] += y;
+
+
+  /* Generate starting offsets into the value table for each length */
+  x[1] = j = 0;
+  p = c + 1;  xp = x + 2;
+  while (--i) {                 /* note that i == g from above */
+    *xp++ = (j += *p++);
+  }
+
+
+  /* Make a table of values in order of bit lengths */
+  p = b;  i = 0;
+  do {
+    if ((j = *p++) != 0)
+      v[x[j]++] = i;
+  } while (++i < n);
+
+
+  /* Generate the Huffman codes and for each, make the table entries */
+  x[0] = i = 0;                 /* first Huffman code is zero */
+  p = v;                        /* grab values in bit order */
+  h = -1;                       /* no tables yet--level -1 */
+  w = -l;                       /* bits decoded == (l * h) */
+  u[0] = (struct huft *)NULL;   /* just to keep compilers happy */
+  q = (struct huft *)NULL;      /* ditto */
+  z = 0;                        /* ditto */
+
+  /* go through the bit lengths (k already is bits in shortest code) */
+  for (; k <= g; k++)
+  {
+    a = c[k];
+    while (a--)
+    {
+      /* here i is the Huffman code of length k bits for value *p */
+      /* make tables up to required level */
+      while (k > w + l)
+      {
+        h++;
+        w += l;                 /* previous table always l bits */
+
+        /* compute minimum size table less than or equal to l bits */
+        z = (z = g - w) > (unsigned)l ? (unsigned)l : z;  /* upper limit on table size */
+        if ((f = 1 << (j = k - w)) > a + 1)     /* try a k-w bit table */
+        {                       /* too few codes for k-w bit table */
+          f -= a + 1;           /* deduct codes from patterns left */
+          xp = c + k;
+          while (++j < z)       /* try smaller tables up to z bits */
+          {
+            if ((f <<= 1) <= *++xp)
+              break;            /* enough codes to use up j bits */
+            f -= *xp;           /* else deduct codes from patterns */
+          }
+        }
+        z = 1 << j;             /* table entries for j-bit table */
+
+        /* allocate and link in new table */
+        if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
+            (struct huft *)NULL)
+        {
+          if (h)
+            huft_free(u[0]);
+          return 3;             /* not enough memory */
+        }
+        hufts += z + 1;         /* track memory usage */
+        *t = q + 1;             /* link to list for huft_free() */
+        *(t = &(q->v.t)) = (struct huft *)NULL;
+        u[h] = ++q;             /* table starts after link */
+
+        /* connect to last table, if there is one */
+        if (h)
+        {
+          x[h] = i;             /* save pattern for backing up */
+          r.b = (uch)l;         /* bits to dump before this table */
+          r.e = (uch)(16 + j);  /* bits in this table */
+          r.v.t = q;            /* pointer to this table */
+          j = i >> (w - l);     /* (get around Turbo C bug) */
+          u[h-1][j] = r;        /* connect to last table */
+        }
+      }
+
+      /* set up table entry in r */
+      r.b = (uch)(k - w);
+      if (p >= v + n)
+        r.e = 99;               /* out of values--invalid code */
+      else if (*p < s)
+      {
+        r.e = (uch)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */
+        r.v.n = (ush)(*p);             /* simple code is just the value */
+	p++;                           /* one compiler does not like *p++ */
+      }
+      else
+      {
+        r.e = (uch)e[*p - s];   /* non-simple--look up in lists */
+        r.v.n = d[*p++ - s];
+      }
+
+      /* fill code-like entries with r */
+      f = 1 << (k - w);
+      for (j = i >> w; j < z; j += f)
+        q[j] = r;
+
+      /* backwards increment the k-bit code i */
+      for (j = 1 << (k - 1); i & j; j >>= 1)
+        i ^= j;
+      i ^= j;
+
+      /* backup over finished tables */
+      while ((i & ((1 << w) - 1)) != x[h])
+      {
+        h--;                    /* don't need to update q */
+        w -= l;
+      }
+    }
+  }
+
+
+  /* Return true (1) if we were given an incomplete table */
+  return y != 0 && g != 1;
+}
+
+
+
+int huft_free(t)
+struct huft *t;         /* table to free */
+/* Free the malloc'ed tables built by huft_build(), which makes a linked
+   list of the tables it made, with the links in a dummy first entry of
+   each table. */
+{
+  register struct huft *p, *q;
+
+
+  /* Go through linked list, freeing from the malloced (t[-1]) address. */
+  p = t;
+  while (p != (struct huft *)NULL)
+  {
+    q = (--p)->v.t;
+    free((char*)p);
+    p = q;
+  }
+  return 0;
+}
+
+
+int inflate_codes(tl, td, bl, bd)
+struct huft *tl, *td;   /* literal/length and distance decoder tables */
+int bl, bd;             /* number of bits decoded by tl[] and td[] */
+/* inflate (decompress) the codes in a deflated (compressed) block.
+   Return an error code or zero if it all goes ok. */
+{
+  register unsigned e;  /* table entry flag/number of extra bits */
+  unsigned n, d;        /* length and index for copy */
+  unsigned w;           /* current window position */
+  struct huft *t;       /* pointer to table entry */
+  unsigned ml, md;      /* masks for bl and bd bits */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+  /* inflate the coded data */
+  ml = mask_bits[bl];           /* precompute masks for speed */
+  md = mask_bits[bd];
+  for (;;)                      /* do until end of block */
+  {
+    NEEDBITS((unsigned)bl)
+    if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
+      do {
+        if (e == 99)
+          return 1;
+        DUMPBITS(t->b)
+        e -= 16;
+        NEEDBITS(e)
+      } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+    DUMPBITS(t->b)
+    if (e == 16)                /* then it's a literal */
+    {
+      slide[w++] = (uch)t->v.n;
+      Tracevv((stderr, "%c", slide[w-1]));
+      if (w == WSIZE)
+      {
+        flush_output(w);
+        w = 0;
+      }
+    }
+    else                        /* it's an EOB or a length */
+    {
+      /* exit if end of block */
+      if (e == 15)
+        break;
+
+      /* get length of block to copy */
+      NEEDBITS(e)
+      n = t->v.n + ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e);
+
+      /* decode distance of block to copy */
+      NEEDBITS((unsigned)bd)
+      if ((e = (t = td + ((unsigned)b & md))->e) > 16)
+        do {
+          if (e == 99)
+            return 1;
+          DUMPBITS(t->b)
+          e -= 16;
+          NEEDBITS(e)
+        } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+      DUMPBITS(t->b)
+      NEEDBITS(e)
+      d = w - t->v.n - ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e)
+      Tracevv((stderr,"\\[%d,%d]", w-d, n));
+
+      /* do the copy */
+      do {
+        n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
+#if !defined(NOMEMCPY) && !defined(DEBUG)
+        if (w - d >= e)         /* (this test assumes unsigned comparison) */
+        {
+          memcpy(slide + w, slide + d, e);
+          w += e;
+          d += e;
+        }
+        else                      /* do it slow to avoid memcpy() overlap */
+#endif /* !NOMEMCPY */
+          do {
+            slide[w++] = slide[d++];
+	    Tracevv((stderr, "%c", slide[w-1]));
+          } while (--e);
+        if (w == WSIZE)
+        {
+          flush_output(w);
+          w = 0;
+        }
+      } while (n);
+    }
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+
+  /* done */
+  return 0;
+}
+
+
+
+int inflate_stored()
+/* "decompress" an inflated type 0 (stored) block. */
+{
+  unsigned n;           /* number of bytes in block */
+  unsigned w;           /* current window position */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+
+  /* go to byte boundary */
+  n = k & 7;
+  DUMPBITS(n);
+
+
+  /* get the length and its complement */
+  NEEDBITS(16)
+  n = ((unsigned)b & 0xffff);
+  DUMPBITS(16)
+  NEEDBITS(16)
+  if (n != (unsigned)((~b) & 0xffff))
+    return 1;                   /* error in compressed data */
+  DUMPBITS(16)
+
+
+  /* read and output the compressed data */
+  while (n--)
+  {
+    NEEDBITS(8)
+    slide[w++] = (uch)b;
+    if (w == WSIZE)
+    {
+      flush_output(w);
+      w = 0;
+    }
+    DUMPBITS(8)
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+  return 0;
+}
+
+
+
+int inflate_fixed()
+/* decompress an inflated type 1 (fixed Huffman codes) block.  We should
+   either replace this with a custom decoder, or at least precompute the
+   Huffman tables. */
+{
+  int i;                /* temporary variable */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned l[288];      /* length list for huft_build */
+
+
+  /* set up literal table */
+  for (i = 0; i < 144; i++)
+    l[i] = 8;
+  for (; i < 256; i++)
+    l[i] = 9;
+  for (; i < 280; i++)
+    l[i] = 7;
+  for (; i < 288; i++)          /* make a complete, but wrong code set */
+    l[i] = 8;
+  bl = 7;
+  if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
+    return i;
+
+
+  /* set up distance table */
+  for (i = 0; i < 30; i++)      /* make an incomplete code set */
+    l[i] = 5;
+  bd = 5;
+  if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
+  {
+    huft_free(tl);
+    return i;
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_dynamic()
+/* decompress an inflated type 2 (dynamic Huffman codes) block. */
+{
+  int i;                /* temporary variables */
+  unsigned j;
+  unsigned l;           /* last length */
+  unsigned m;           /* mask for bit lengths table */
+  unsigned n;           /* number of lengths to get */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned nb;          /* number of bit length codes */
+  unsigned nl;          /* number of literal/length codes */
+  unsigned nd;          /* number of distance codes */
+#ifdef PKZIP_BUG_WORKAROUND
+  unsigned ll[288+32];  /* literal/length and distance code lengths */
+#else
+  unsigned ll[286+30];  /* literal/length and distance code lengths */
+#endif
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in table lengths */
+  NEEDBITS(5)
+  nl = 257 + ((unsigned)b & 0x1f);      /* number of literal/length codes */
+  DUMPBITS(5)
+  NEEDBITS(5)
+  nd = 1 + ((unsigned)b & 0x1f);        /* number of distance codes */
+  DUMPBITS(5)
+  NEEDBITS(4)
+  nb = 4 + ((unsigned)b & 0xf);         /* number of bit length codes */
+  DUMPBITS(4)
+#ifdef PKZIP_BUG_WORKAROUND
+  if (nl > 288 || nd > 32)
+#else
+  if (nl > 286 || nd > 30)
+#endif
+    return 1;                   /* bad lengths */
+
+
+  /* read in bit-length-code lengths */
+  for (j = 0; j < nb; j++)
+  {
+    NEEDBITS(3)
+    ll[border[j]] = (unsigned)b & 7;
+    DUMPBITS(3)
+  }
+  for (; j < 19; j++)
+    ll[border[j]] = 0;
+
+
+  /* build decoding table for trees--single level, 7 bit lookup */
+  bl = 7;
+  if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
+  {
+    if (i == 1)
+      huft_free(tl);
+    return i;                   /* incomplete code set */
+  }
+
+
+  /* read in literal and distance code lengths */
+  n = nl + nd;
+  m = mask_bits[bl];
+  i = l = 0;
+  while ((unsigned)i < n)
+  {
+    NEEDBITS((unsigned)bl)
+    j = (td = tl + ((unsigned)b & m))->b;
+    DUMPBITS(j)
+    j = td->v.n;
+    if (j < 16)                 /* length of code in bits (0..15) */
+      ll[i++] = l = j;          /* save last length in l */
+    else if (j == 16)           /* repeat last length 3 to 6 times */
+    {
+      NEEDBITS(2)
+      j = 3 + ((unsigned)b & 3);
+      DUMPBITS(2)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = l;
+    }
+    else if (j == 17)           /* 3 to 10 zero length codes */
+    {
+      NEEDBITS(3)
+      j = 3 + ((unsigned)b & 7);
+      DUMPBITS(3)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+    else                        /* j == 18: 11 to 138 zero length codes */
+    {
+      NEEDBITS(7)
+      j = 11 + ((unsigned)b & 0x7f);
+      DUMPBITS(7)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+  }
+
+
+  /* free decoding table for trees */
+  huft_free(tl);
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* build the decoding tables for literal/length and distance codes */
+  bl = lbits;
+  if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete literal tree\n");
+      huft_free(tl);
+    }
+    return i;                   /* incomplete code set */
+  }
+  bd = dbits;
+  if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete distance tree\n");
+#ifdef PKZIP_BUG_WORKAROUND
+      i = 0;
+    }
+#else
+      huft_free(td);
+    }
+    huft_free(tl);
+    return i;                   /* incomplete code set */
+#endif
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_block(e)
+int *e;                 /* last block flag */
+/* decompress an inflated block */
+{
+  unsigned t;           /* block type */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in last block bit */
+  NEEDBITS(1)
+  *e = (int)b & 1;
+  DUMPBITS(1)
+
+
+  /* read in block type */
+  NEEDBITS(2)
+  t = (unsigned)b & 3;
+  DUMPBITS(2)
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* inflate that block type */
+  if (t == 2)
+    return inflate_dynamic();
+  if (t == 0)
+    return inflate_stored();
+  if (t == 1)
+    return inflate_fixed();
+
+
+  /* bad block type */
+  return 2;
+}
+
+
+
+int inflate()
+/* decompress an inflated entry */
+{
+  int e;                /* last block flag */
+  int r;                /* result code */
+  unsigned h;           /* maximum struct huft's malloc'ed */
+
+
+  /* initialize window, bit buffer */
+  wp = 0;
+  bk = 0;
+  bb = 0;
+
+
+  /* decompress until the last block */
+  h = 0;
+  do {
+    hufts = 0;
+    if ((r = inflate_block(&e)) != 0)
+      return r;
+    if (hufts > h)
+      h = hufts;
+  } while (!e);
+
+  /* Undo too much lookahead. The next read will be byte aligned so we
+   * can discard unused bits in the last meaningful byte.
+   */
+  while (bk >= 8) {
+    bk -= 8;
+    inptr--;
+  }
+
+  /* flush out slide */
+  flush_output(wp);
+
+
+  /* return success */
+#ifdef DEBUG
+  fprintf(stderr, "<%u> ", h);
+#endif /* DEBUG */
+  return 0;
+}
diff --git a/usr/gzip/revision.h b/usr/gzip/revision.h
new file mode 100644
index 0000000..736020b
--- /dev/null
+++ b/usr/gzip/revision.h
@@ -0,0 +1,11 @@
+/* revision.h -- define the version number
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#define VERSION "1.2.4"
+#define PATCHLEVEL 0
+#define REVDATE "18 Aug 93"
+
+/* $Id: revision.h,v 1.1 2002/08/18 00:59:21 hpa Exp $ */
diff --git a/usr/gzip/tailor.h b/usr/gzip/tailor.h
new file mode 100644
index 0000000..849e589
--- /dev/null
+++ b/usr/gzip/tailor.h
@@ -0,0 +1,50 @@
+/* tailor.h -- target dependent definitions
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/* The target dependent definitions should be defined here only.
+ * The target dependent functions should be defined in tailor.c.
+ */
+
+/* $Id: tailor.h,v 1.1 2002/08/18 00:59:21 hpa Exp $ */
+
+	/* Common defaults */
+
+#ifndef OS_CODE
+#  define OS_CODE  0x03  /* assume Unix */
+#endif
+
+#define PATH_SEP '/'
+
+#ifndef casemap
+#  define casemap(c) (c)
+#endif
+
+#ifndef OPTIONS_VAR
+#  define OPTIONS_VAR "GZIP"
+#endif
+
+#ifndef Z_SUFFIX
+#  define Z_SUFFIX ".gz"
+#endif
+
+#define MAX_SUFFIX  30
+
+#ifndef MIN_PART
+#  define MIN_PART 3
+   /* keep at least MIN_PART chars between dots in a file name. */
+#endif
+
+#ifndef RECORD_IO
+#  define RECORD_IO 0
+#endif
+
+#ifndef get_char
+#  define get_char() get_byte()
+#endif
+
+#ifndef put_char
+#  define put_char(c) put_byte(c)
+#endif
diff --git a/usr/gzip/trees.c b/usr/gzip/trees.c
new file mode 100644
index 0000000..75efc97
--- /dev/null
+++ b/usr/gzip/trees.c
@@ -0,0 +1,1075 @@
+/* trees.c -- output deflated data using Huffman coding
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/*
+ *  PURPOSE
+ *
+ *      Encode various sets of source values using variable-length
+ *      binary code trees.
+ *
+ *  DISCUSSION
+ *
+ *      The PKZIP "deflation" process uses several Huffman trees. The more
+ *      common source values are represented by shorter bit sequences.
+ *
+ *      Each code tree is stored in the ZIP file in a compressed form
+ *      which is itself a Huffman encoding of the lengths of
+ *      all the code strings (in ascending order by source values).
+ *      The actual code strings are reconstructed from the lengths in
+ *      the UNZIP process, as described in the "application note"
+ *      (APPNOTE.TXT) distributed as part of PKWARE's PKZIP program.
+ *
+ *  REFERENCES
+ *
+ *      Lynch, Thomas J.
+ *          Data Compression:  Techniques and Applications, pp. 53-55.
+ *          Lifetime Learning Publications, 1985.  ISBN 0-534-03418-7.
+ *
+ *      Storer, James A.
+ *          Data Compression:  Methods and Theory, pp. 49-50.
+ *          Computer Science Press, 1988.  ISBN 0-7167-8156-5.
+ *
+ *      Sedgewick, R.
+ *          Algorithms, p290.
+ *          Addison-Wesley, 1983. ISBN 0-201-06672-6.
+ *
+ *  INTERFACE
+ *
+ *      void ct_init (ush *attr, int *methodp)
+ *          Allocate the match buffer, initialize the various tables and save
+ *          the location of the internal file attribute (ascii/binary) and
+ *          method (DEFLATE/STORE)
+ *
+ *      void ct_tally (int dist, int lc);
+ *          Save the match info and tally the frequency counts.
+ *
+ *      long flush_block (char *buf, ulg stored_len, int eof)
+ *          Determine the best encoding for the current block: dynamic trees,
+ *          static trees or store, and output the encoded block to the zip
+ *          file. Returns the total compressed length for the file so far.
+ *
+ */
+
+#include <ctype.h>
+
+#include "tailor.h"
+#include "gzip.h"
+
+#ifdef RCSID
+static char rcsid[] = "$Id: trees.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+/* ===========================================================================
+ * Constants
+ */
+
+#define MAX_BITS 15
+/* All codes must not exceed MAX_BITS bits */
+
+#define MAX_BL_BITS 7
+/* Bit length codes must not exceed MAX_BL_BITS bits */
+
+#define LENGTH_CODES 29
+/* number of length codes, not counting the special END_BLOCK code */
+
+#define LITERALS  256
+/* number of literal bytes 0..255 */
+
+#define END_BLOCK 256
+/* end of block literal code */
+
+#define L_CODES (LITERALS+1+LENGTH_CODES)
+/* number of Literal or Length codes, including the END_BLOCK code */
+
+#define D_CODES   30
+/* number of distance codes */
+
+#define BL_CODES  19
+/* number of codes used to transfer the bit lengths */
+
+
+local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
+   = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
+
+local int extra_dbits[D_CODES] /* extra bits for each distance code */
+   = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
+
+local int extra_blbits[BL_CODES]/* extra bits for each bit length code */
+   = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
+
+#define STORED_BLOCK 0
+#define STATIC_TREES 1
+#define DYN_TREES    2
+/* The three kinds of block type */
+
+#ifndef LIT_BUFSIZE
+#  ifdef SMALL_MEM
+#    define LIT_BUFSIZE  0x2000
+#  else
+#  ifdef MEDIUM_MEM
+#    define LIT_BUFSIZE  0x4000
+#  else
+#    define LIT_BUFSIZE  0x8000
+#  endif
+#  endif
+#endif
+#ifndef DIST_BUFSIZE
+#  define DIST_BUFSIZE  LIT_BUFSIZE
+#endif
+/* Sizes of match buffers for literals/lengths and distances.  There are
+ * 4 reasons for limiting LIT_BUFSIZE to 64K:
+ *   - frequencies can be kept in 16 bit counters
+ *   - if compression is not successful for the first block, all input data is
+ *     still in the window so we can still emit a stored block even when input
+ *     comes from standard input.  (This can also be done for all blocks if
+ *     LIT_BUFSIZE is not greater than 32K.)
+ *   - if compression is not successful for a file smaller than 64K, we can
+ *     even emit a stored file instead of a stored block (saving 5 bytes).
+ *   - creating new Huffman trees less frequently may not provide fast
+ *     adaptation to changes in the input data statistics. (Take for
+ *     example a binary file with poorly compressible code followed by
+ *     a highly compressible string table.) Smaller buffer sizes give
+ *     fast adaptation but have of course the overhead of transmitting trees
+ *     more frequently.
+ *   - I can't count above 4
+ * The current code is general and allows DIST_BUFSIZE < LIT_BUFSIZE (to save
+ * memory at the expense of compression). Some optimizations would be possible
+ * if we rely on DIST_BUFSIZE == LIT_BUFSIZE.
+ */
+#if LIT_BUFSIZE > INBUFSIZ
+    error cannot overlay l_buf and inbuf
+#endif
+
+#define REP_3_6      16
+/* repeat previous bit length 3-6 times (2 bits of repeat count) */
+
+#define REPZ_3_10    17
+/* repeat a zero length 3-10 times  (3 bits of repeat count) */
+
+#define REPZ_11_138  18
+/* repeat a zero length 11-138 times  (7 bits of repeat count) */
+
+/* ===========================================================================
+ * Local data
+ */
+
+/* Data structure describing a single value and its code string. */
+typedef struct ct_data {
+    union {
+        ush  freq;       /* frequency count */
+        ush  code;       /* bit string */
+    } fc;
+    union {
+        ush  dad;        /* father node in Huffman tree */
+        ush  len;        /* length of bit string */
+    } dl;
+} ct_data;
+
+#define Freq fc.freq
+#define Code fc.code
+#define Dad  dl.dad
+#define Len  dl.len
+
+#define HEAP_SIZE (2*L_CODES+1)
+/* maximum heap size */
+
+local ct_data dyn_ltree[HEAP_SIZE];   /* literal and length tree */
+local ct_data dyn_dtree[2*D_CODES+1]; /* distance tree */
+
+local ct_data static_ltree[L_CODES+2];
+/* The static literal tree. Since the bit lengths are imposed, there is no
+ * need for the L_CODES extra codes used during heap construction. However
+ * The codes 286 and 287 are needed to build a canonical tree (see ct_init
+ * below).
+ */
+
+local ct_data static_dtree[D_CODES];
+/* The static distance tree. (Actually a trivial tree since all codes use
+ * 5 bits.)
+ */
+
+local ct_data bl_tree[2*BL_CODES+1];
+/* Huffman tree for the bit lengths */
+
+typedef struct tree_desc {
+    ct_data *dyn_tree;      /* the dynamic tree */
+    ct_data *static_tree;   /* corresponding static tree or NULL */
+    int     *extra_bits;    /* extra bits for each code or NULL */
+    int     extra_base;          /* base index for extra_bits */
+    int     elems;               /* max number of elements in the tree */
+    int     max_length;          /* max bit length for the codes */
+    int     max_code;            /* largest code with non zero frequency */
+} tree_desc;
+
+local tree_desc l_desc =
+{dyn_ltree, static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS, 0};
+
+local tree_desc d_desc =
+{dyn_dtree, static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS, 0};
+
+local tree_desc bl_desc =
+{bl_tree, (ct_data *)0, extra_blbits, 0,      BL_CODES, MAX_BL_BITS, 0};
+
+
+local ush bl_count[MAX_BITS+1];
+/* number of codes at each bit length for an optimal tree */
+
+local uch bl_order[BL_CODES]
+   = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
+/* The lengths of the bit length codes are sent in order of decreasing
+ * probability, to avoid transmitting the lengths for unused bit length codes.
+ */
+
+local int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
+local int heap_len;               /* number of elements in the heap */
+local int heap_max;               /* element of largest frequency */
+/* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
+ * The same heap array is used to build all trees.
+ */
+
+local uch depth[2*L_CODES+1];
+/* Depth of each subtree used as tie breaker for trees of equal frequency */
+
+local uch length_code[MAX_MATCH-MIN_MATCH+1];
+/* length code for each normalized match length (0 == MIN_MATCH) */
+
+local uch dist_code[512];
+/* distance codes. The first 256 values correspond to the distances
+ * 3 .. 258, the last 256 values correspond to the top 8 bits of
+ * the 15 bit distances.
+ */
+
+local int base_length[LENGTH_CODES];
+/* First normalized length for each code (0 = MIN_MATCH) */
+
+local int base_dist[D_CODES];
+/* First normalized distance for each code (0 = distance of 1) */
+
+#define l_buf inbuf
+/* DECLARE(uch, l_buf, LIT_BUFSIZE);  buffer for literals or lengths */
+
+/* DECLARE(ush, d_buf, DIST_BUFSIZE); buffer for distances */
+
+local uch flag_buf[(LIT_BUFSIZE/8)];
+/* flag_buf is a bit array distinguishing literals from lengths in
+ * l_buf, thus indicating the presence or absence of a distance.
+ */
+
+local unsigned last_lit;    /* running index in l_buf */
+local unsigned last_dist;   /* running index in d_buf */
+local unsigned last_flags;  /* running index in flag_buf */
+local uch flags;            /* current flags not yet saved in flag_buf */
+local uch flag_bit;         /* current bit used in flags */
+/* bits are filled in flags starting at bit 0 (least significant).
+ * Note: these flags are overkill in the current code since we don't
+ * take advantage of DIST_BUFSIZE == LIT_BUFSIZE.
+ */
+
+local ulg opt_len;        /* bit length of current block with optimal trees */
+local ulg static_len;     /* bit length of current block with static trees */
+
+local ulg compressed_len; /* total bit length of compressed file */
+
+local ulg input_len;      /* total byte length of input file */
+/* input_len is for debugging only since we can get it by other means. */
+
+ush *file_type;        /* pointer to UNKNOWN, BINARY or ASCII */
+int *file_method;      /* pointer to DEFLATE or STORE */
+
+#ifdef DEBUG
+extern ulg bits_sent;  /* bit length of the compressed data */
+extern long isize;     /* byte length of input file */
+#endif
+
+extern long block_start;       /* window offset of current block */
+extern unsigned strstart; /* window offset of current string */
+
+/* ===========================================================================
+ * Local (static) routines in this file.
+ */
+
+local void init_block     OF((void));
+local void pqdownheap     OF((ct_data *tree, int k));
+local void gen_bitlen     OF((tree_desc *desc));
+local void gen_codes      OF((ct_data *tree, int max_code));
+local void build_tree     OF((tree_desc *desc));
+local void scan_tree      OF((ct_data *tree, int max_code));
+local void send_tree      OF((ct_data *tree, int max_code));
+local int  build_bl_tree  OF((void));
+local void send_all_trees OF((int lcodes, int dcodes, int blcodes));
+local void compress_block OF((ct_data *ltree, ct_data *dtree));
+local void set_file_type  OF((void));
+
+
+#ifndef DEBUG
+#  define send_code(c, tree) send_bits(tree[c].Code, tree[c].Len)
+   /* Send a code of the given tree. c and tree must not have side effects */
+
+#else /* DEBUG */
+#  define send_code(c, tree) \
+     { if (verbose>1) fprintf(stderr,"\ncd %3d ",(c)); \
+       send_bits(tree[c].Code, tree[c].Len); }
+#endif
+
+#define d_code(dist) \
+   ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
+/* Mapping from a distance to a distance code. dist is the distance - 1 and
+ * must not have side effects. dist_code[256] and dist_code[257] are never
+ * used.
+ */
+
+#define MAX(a,b) (a >= b ? a : b)
+/* the arguments must not have side effects */
+
+/* ===========================================================================
+ * Allocate the match buffer, initialize the various tables and save the
+ * location of the internal file attribute (ascii/binary) and method
+ * (DEFLATE/STORE).
+ */
+void ct_init(attr, methodp)
+    ush  *attr;   /* pointer to internal file attribute */
+    int  *methodp; /* pointer to compression method */
+{
+    int n;        /* iterates over tree elements */
+    int bits;     /* bit counter */
+    int length;   /* length value */
+    int code;     /* code value */
+    int dist;     /* distance index */
+
+    file_type = attr;
+    file_method = methodp;
+    compressed_len = input_len = 0L;
+
+    if (static_dtree[0].Len != 0) return; /* ct_init already called */
+
+    /* Initialize the mapping length (0..255) -> length code (0..28) */
+    length = 0;
+    for (code = 0; code < LENGTH_CODES-1; code++) {
+        base_length[code] = length;
+        for (n = 0; n < (1<<extra_lbits[code]); n++) {
+            length_code[length++] = (uch)code;
+        }
+    }
+    Assert (length == 256, "ct_init: length != 256");
+    /* Note that the length 255 (match length 258) can be represented
+     * in two different ways: code 284 + 5 bits or code 285, so we
+     * overwrite length_code[255] to use the best encoding:
+     */
+    length_code[length-1] = (uch)code;
+
+    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
+    dist = 0;
+    for (code = 0 ; code < 16; code++) {
+        base_dist[code] = dist;
+        for (n = 0; n < (1<<extra_dbits[code]); n++) {
+            dist_code[dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "ct_init: dist != 256");
+    dist >>= 7; /* from now on, all distances are divided by 128 */
+    for ( ; code < D_CODES; code++) {
+        base_dist[code] = dist << 7;
+        for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
+            dist_code[256 + dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "ct_init: 256+dist != 512");
+
+    /* Construct the codes of the static literal tree */
+    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
+    n = 0;
+    while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
+    while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
+    while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
+    while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
+    /* Codes 286 and 287 do not exist, but we must include them in the
+     * tree construction to get a canonical Huffman tree (longest code
+     * all ones)
+     */
+    gen_codes((ct_data *)static_ltree, L_CODES+1);
+
+    /* The static distance tree is trivial: */
+    for (n = 0; n < D_CODES; n++) {
+        static_dtree[n].Len = 5;
+        static_dtree[n].Code = bi_reverse(n, 5);
+    }
+
+    /* Initialize the first block of the first file: */
+    init_block();
+}
+
+/* ===========================================================================
+ * Initialize a new block.
+ */
+local void init_block()
+{
+    int n; /* iterates over tree elements */
+
+    /* Initialize the trees. */
+    for (n = 0; n < L_CODES;  n++) dyn_ltree[n].Freq = 0;
+    for (n = 0; n < D_CODES;  n++) dyn_dtree[n].Freq = 0;
+    for (n = 0; n < BL_CODES; n++) bl_tree[n].Freq = 0;
+
+    dyn_ltree[END_BLOCK].Freq = 1;
+    opt_len = static_len = 0L;
+    last_lit = last_dist = last_flags = 0;
+    flags = 0; flag_bit = 1;
+}
+
+#define SMALLEST 1
+/* Index within the heap array of least frequent node in the Huffman tree */
+
+
+/* ===========================================================================
+ * Remove the smallest element from the heap and recreate the heap with
+ * one less element. Updates heap and heap_len.
+ */
+#define pqremove(tree, top) \
+{\
+    top = heap[SMALLEST]; \
+    heap[SMALLEST] = heap[heap_len--]; \
+    pqdownheap(tree, SMALLEST); \
+}
+
+/* ===========================================================================
+ * Compares to subtrees, using the tree depth as tie breaker when
+ * the subtrees have equal frequency. This minimizes the worst case length.
+ */
+#define smaller(tree, n, m) \
+   (tree[n].Freq < tree[m].Freq || \
+   (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
+
+/* ===========================================================================
+ * Restore the heap property by moving down the tree starting at node k,
+ * exchanging a node with the smallest of its two sons if necessary, stopping
+ * when the heap property is re-established (each father smaller than its
+ * two sons).
+ */
+local void pqdownheap(tree, k)
+    ct_data *tree;  /* the tree to restore */
+    int k;               /* node to move down */
+{
+    int v = heap[k];
+    int j = k << 1;  /* left son of k */
+    while (j <= heap_len) {
+        /* Set j to the smallest of the two sons: */
+        if (j < heap_len && smaller(tree, heap[j+1], heap[j])) j++;
+
+        /* Exit if v is smaller than both sons */
+        if (smaller(tree, v, heap[j])) break;
+
+        /* Exchange v with the smallest son */
+        heap[k] = heap[j];  k = j;
+
+        /* And continue down the tree, setting j to the left son of k */
+        j <<= 1;
+    }
+    heap[k] = v;
+}
+
+/* ===========================================================================
+ * Compute the optimal bit lengths for a tree and update the total bit length
+ * for the current block.
+ * IN assertion: the fields freq and dad are set, heap[heap_max] and
+ *    above are the tree nodes sorted by increasing frequency.
+ * OUT assertions: the field len is set to the optimal bit length, the
+ *     array bl_count contains the frequencies for each bit length.
+ *     The length opt_len is updated; static_len is also updated if stree is
+ *     not null.
+ */
+local void gen_bitlen(desc)
+    tree_desc *desc; /* the tree descriptor */
+{
+    ct_data *tree  = desc->dyn_tree;
+    int *extra     = desc->extra_bits;
+    int base            = desc->extra_base;
+    int max_code        = desc->max_code;
+    int max_length      = desc->max_length;
+    ct_data *stree = desc->static_tree;
+    int h;              /* heap index */
+    int n, m;           /* iterate over the tree elements */
+    int bits;           /* bit length */
+    int xbits;          /* extra bits */
+    ush f;              /* frequency */
+    int overflow = 0;   /* number of elements with bit length too large */
+
+    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
+
+    /* In a first pass, compute the optimal bit lengths (which may
+     * overflow in the case of the bit length tree).
+     */
+    tree[heap[heap_max]].Len = 0; /* root of the heap */
+
+    for (h = heap_max+1; h < HEAP_SIZE; h++) {
+        n = heap[h];
+        bits = tree[tree[n].Dad].Len + 1;
+        if (bits > max_length) bits = max_length, overflow++;
+        tree[n].Len = (ush)bits;
+        /* We overwrite tree[n].Dad which is no longer needed */
+
+        if (n > max_code) continue; /* not a leaf node */
+
+        bl_count[bits]++;
+        xbits = 0;
+        if (n >= base) xbits = extra[n-base];
+        f = tree[n].Freq;
+        opt_len += (ulg)f * (bits + xbits);
+        if (stree) static_len += (ulg)f * (stree[n].Len + xbits);
+    }
+    if (overflow == 0) return;
+
+    Trace((stderr,"\nbit length overflow\n"));
+    /* This happens for example on obj2 and pic of the Calgary corpus */
+
+    /* Find the first bit length which could increase: */
+    do {
+        bits = max_length-1;
+        while (bl_count[bits] == 0) bits--;
+        bl_count[bits]--;      /* move one leaf down the tree */
+        bl_count[bits+1] += 2; /* move one overflow item as its brother */
+        bl_count[max_length]--;
+        /* The brother of the overflow item also moves one step up,
+         * but this does not affect bl_count[max_length]
+         */
+        overflow -= 2;
+    } while (overflow > 0);
+
+    /* Now recompute all bit lengths, scanning in increasing frequency.
+     * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
+     * lengths instead of fixing only the wrong ones. This idea is taken
+     * from 'ar' written by Haruhiko Okumura.)
+     */
+    for (bits = max_length; bits != 0; bits--) {
+        n = bl_count[bits];
+        while (n != 0) {
+            m = heap[--h];
+            if (m > max_code) continue;
+            if (tree[m].Len != (unsigned) bits) {
+                Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
+                opt_len += ((long)bits-(long)tree[m].Len)*(long)tree[m].Freq;
+                tree[m].Len = (ush)bits;
+            }
+            n--;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Generate the codes for a given tree and bit counts (which need not be
+ * optimal).
+ * IN assertion: the array bl_count contains the bit length statistics for
+ * the given tree and the field len is set for all tree elements.
+ * OUT assertion: the field code is set for all tree elements of non
+ *     zero code length.
+ */
+local void gen_codes (tree, max_code)
+    ct_data *tree;        /* the tree to decorate */
+    int max_code;              /* largest code with non zero frequency */
+{
+    ush next_code[MAX_BITS+1]; /* next code value for each bit length */
+    ush code = 0;              /* running code value */
+    int bits;                  /* bit index */
+    int n;                     /* code index */
+
+    /* The distribution counts are first used to generate the code values
+     * without bit reversal.
+     */
+    for (bits = 1; bits <= MAX_BITS; bits++) {
+        next_code[bits] = code = (code + bl_count[bits-1]) << 1;
+    }
+    /* Check that the bit counts in bl_count are consistent. The last code
+     * must be all ones.
+     */
+    Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
+            "inconsistent bit counts");
+    Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
+
+    for (n = 0;  n <= max_code; n++) {
+        int len = tree[n].Len;
+        if (len == 0) continue;
+        /* Now reverse the bits */
+        tree[n].Code = bi_reverse(next_code[len]++, len);
+
+        Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
+             n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
+    }
+}
+
+/* ===========================================================================
+ * Construct one Huffman tree and assigns the code bit strings and lengths.
+ * Update the total bit length for the current block.
+ * IN assertion: the field freq is set for all tree elements.
+ * OUT assertions: the fields len and code are set to the optimal bit length
+ *     and corresponding code. The length opt_len is updated; static_len is
+ *     also updated if stree is not null. The field max_code is set.
+ */
+local void build_tree(desc)
+    tree_desc *desc; /* the tree descriptor */
+{
+    ct_data *tree   = desc->dyn_tree;
+    ct_data *stree  = desc->static_tree;
+    int elems            = desc->elems;
+    int n, m;          /* iterate over heap elements */
+    int max_code = -1; /* largest code with non zero frequency */
+    int node = elems;  /* next internal node of the tree */
+
+    /* Construct the initial heap, with least frequent element in
+     * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
+     * heap[0] is not used.
+     */
+    heap_len = 0, heap_max = HEAP_SIZE;
+
+    for (n = 0; n < elems; n++) {
+        if (tree[n].Freq != 0) {
+            heap[++heap_len] = max_code = n;
+            depth[n] = 0;
+        } else {
+            tree[n].Len = 0;
+        }
+    }
+
+    /* The pkzip format requires that at least one distance code exists,
+     * and that at least one bit should be sent even if there is only one
+     * possible code. So to avoid special checks later on we force at least
+     * two codes of non zero frequency.
+     */
+    while (heap_len < 2) {
+        int new = heap[++heap_len] = (max_code < 2 ? ++max_code : 0);
+        tree[new].Freq = 1;
+        depth[new] = 0;
+        opt_len--; if (stree) static_len -= stree[new].Len;
+        /* new is 0 or 1 so it does not have extra bits */
+    }
+    desc->max_code = max_code;
+
+    /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
+     * establish sub-heaps of increasing lengths:
+     */
+    for (n = heap_len/2; n >= 1; n--) pqdownheap(tree, n);
+
+    /* Construct the Huffman tree by repeatedly combining the least two
+     * frequent nodes.
+     */
+    do {
+        pqremove(tree, n);   /* n = node of least frequency */
+        m = heap[SMALLEST];  /* m = node of next least frequency */
+
+        heap[--heap_max] = n; /* keep the nodes sorted by frequency */
+        heap[--heap_max] = m;
+
+        /* Create a new node father of n and m */
+        tree[node].Freq = tree[n].Freq + tree[m].Freq;
+        depth[node] = (uch) (MAX(depth[n], depth[m]) + 1);
+        tree[n].Dad = tree[m].Dad = (ush)node;
+#ifdef DUMP_BL_TREE
+        if (tree == bl_tree) {
+            fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
+                    node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
+        }
+#endif
+        /* and insert the new node in the heap */
+        heap[SMALLEST] = node++;
+        pqdownheap(tree, SMALLEST);
+
+    } while (heap_len >= 2);
+
+    heap[--heap_max] = heap[SMALLEST];
+
+    /* At this point, the fields freq and dad are set. We can now
+     * generate the bit lengths.
+     */
+    gen_bitlen((tree_desc *)desc);
+
+    /* The field len is now set, we can generate the bit codes */
+    gen_codes ((ct_data *)tree, max_code);
+}
+
+/* ===========================================================================
+ * Scan a literal or distance tree to determine the frequencies of the codes
+ * in the bit length tree. Updates opt_len to take into account the repeat
+ * counts. (The contribution of the bit length codes will be added later
+ * during the construction of bl_tree.)
+ */
+local void scan_tree (tree, max_code)
+    ct_data *tree; /* the tree to be scanned */
+    int max_code;       /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    if (nextlen == 0) max_count = 138, min_count = 3;
+    tree[max_code+1].Len = (ush)0xffff; /* guard */
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            bl_tree[curlen].Freq += count;
+        } else if (curlen != 0) {
+            if (curlen != prevlen) bl_tree[curlen].Freq++;
+            bl_tree[REP_3_6].Freq++;
+        } else if (count <= 10) {
+            bl_tree[REPZ_3_10].Freq++;
+        } else {
+            bl_tree[REPZ_11_138].Freq++;
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Send a literal or distance tree in compressed form, using the codes in
+ * bl_tree.
+ */
+local void send_tree (tree, max_code)
+    ct_data *tree; /* the tree to be scanned */
+    int max_code;       /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    /* tree[max_code+1].Len = -1; */  /* guard already set */
+    if (nextlen == 0) max_count = 138, min_count = 3;
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            do { send_code(curlen, bl_tree); } while (--count != 0);
+
+        } else if (curlen != 0) {
+            if (curlen != prevlen) {
+                send_code(curlen, bl_tree); count--;
+            }
+            Assert(count >= 3 && count <= 6, " 3_6?");
+            send_code(REP_3_6, bl_tree); send_bits(count-3, 2);
+
+        } else if (count <= 10) {
+            send_code(REPZ_3_10, bl_tree); send_bits(count-3, 3);
+
+        } else {
+            send_code(REPZ_11_138, bl_tree); send_bits(count-11, 7);
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Construct the Huffman tree for the bit lengths and return the index in
+ * bl_order of the last bit length code to send.
+ */
+local int build_bl_tree()
+{
+    int max_blindex;  /* index of last bit length code of non zero freq */
+
+    /* Determine the bit length frequencies for literal and distance trees */
+    scan_tree((ct_data *)dyn_ltree, l_desc.max_code);
+    scan_tree((ct_data *)dyn_dtree, d_desc.max_code);
+
+    /* Build the bit length tree: */
+    build_tree((tree_desc *)(&bl_desc));
+    /* opt_len now includes the length of the tree representations, except
+     * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
+     */
+
+    /* Determine the number of bit length codes to send. The pkzip format
+     * requires that at least 4 bit length codes be sent. (appnote.txt says
+     * 3 but the actual value used is 4.)
+     */
+    for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
+        if (bl_tree[bl_order[max_blindex]].Len != 0) break;
+    }
+    /* Update opt_len to include the bit length tree and counts */
+    opt_len += 3*(max_blindex+1) + 5+5+4;
+    Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", opt_len, static_len));
+
+    return max_blindex;
+}
+
+/* ===========================================================================
+ * Send the header for a block using dynamic Huffman trees: the counts, the
+ * lengths of the bit length codes, the literal tree and the distance tree.
+ * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
+ */
+local void send_all_trees(lcodes, dcodes, blcodes)
+    int lcodes, dcodes, blcodes; /* number of codes for each tree */
+{
+    int rank;                    /* index in bl_order */
+
+    Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
+    Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
+            "too many codes");
+    Tracev((stderr, "\nbl counts: "));
+    send_bits(lcodes-257, 5); /* not +255 as stated in appnote.txt */
+    send_bits(dcodes-1,   5);
+    send_bits(blcodes-4,  4); /* not -3 as stated in appnote.txt */
+    for (rank = 0; rank < blcodes; rank++) {
+        Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
+        send_bits(bl_tree[bl_order[rank]].Len, 3);
+    }
+    Tracev((stderr, "\nbl tree: sent %ld", bits_sent));
+
+    send_tree((ct_data *)dyn_ltree, lcodes-1); /* send the literal tree */
+    Tracev((stderr, "\nlit tree: sent %ld", bits_sent));
+
+    send_tree((ct_data *)dyn_dtree, dcodes-1); /* send the distance tree */
+    Tracev((stderr, "\ndist tree: sent %ld", bits_sent));
+}
+
+/* ===========================================================================
+ * Determine the best encoding for the current block: dynamic trees, static
+ * trees or store, and output the encoded block to the zip file. This function
+ * returns the total compressed length for the file so far.
+ */
+ulg flush_block(buf, stored_len, eof)
+    char *buf;        /* input block, or NULL if too old */
+    ulg stored_len;   /* length of input block */
+    int eof;          /* true if this is the last block for a file */
+{
+    ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
+    int max_blindex;  /* index of last bit length code of non zero freq */
+
+    flag_buf[last_flags] = flags; /* Save the flags for the last 8 items */
+
+     /* Check if the file is ascii or binary */
+    if (*file_type == (ush)UNKNOWN) set_file_type();
+
+    /* Construct the literal and distance trees */
+    build_tree((tree_desc *)(&l_desc));
+    Tracev((stderr, "\nlit data: dyn %ld, stat %ld", opt_len, static_len));
+
+    build_tree((tree_desc *)(&d_desc));
+    Tracev((stderr, "\ndist data: dyn %ld, stat %ld", opt_len, static_len));
+    /* At this point, opt_len and static_len are the total bit lengths of
+     * the compressed block data, excluding the tree representations.
+     */
+
+    /* Build the bit length tree for the above two trees, and get the index
+     * in bl_order of the last bit length code to send.
+     */
+    max_blindex = build_bl_tree();
+
+    /* Determine the best encoding. Compute first the block length in bytes */
+    opt_lenb = (opt_len+3+7)>>3;
+    static_lenb = (static_len+3+7)>>3;
+    input_len += stored_len; /* for debugging only */
+
+    Trace((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ",
+            opt_lenb, opt_len, static_lenb, static_len, stored_len,
+            last_lit, last_dist));
+
+    if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+
+    /* If compression failed and this is the first and last block,
+     * and if the zip file can be seeked (to rewrite the local header),
+     * the whole file is transformed into a stored file:
+     */
+#ifdef FORCE_METHOD
+    if (level == 1 && eof && compressed_len == 0L) { /* force stored file */
+#else
+    if (stored_len <= opt_lenb && eof && compressed_len == 0L && seekable()) {
+#endif
+        /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
+        if (buf == (char*)0) error ("block vanished");
+
+        copy_block(buf, (unsigned)stored_len, 0); /* without header */
+        compressed_len = stored_len << 3;
+        *file_method = STORED;
+
+#ifdef FORCE_METHOD
+    } else if (level == 2 && buf != (char*)0) { /* force stored block */
+#else
+    } else if (stored_len+4 <= opt_lenb && buf != (char*)0) {
+                       /* 4: two words for the lengths */
+#endif
+        /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
+         * Otherwise we can't have processed more than WSIZE input bytes since
+         * the last block flush, because compression would have been
+         * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
+         * transform a block into a stored block.
+         */
+        send_bits((STORED_BLOCK<<1)+eof, 3);  /* send block type */
+        compressed_len = (compressed_len + 3 + 7) & ~7L;
+        compressed_len += (stored_len + 4) << 3;
+
+        copy_block(buf, (unsigned)stored_len, 1); /* with header */
+
+#ifdef FORCE_METHOD
+    } else if (level == 3) { /* force static trees */
+#else
+    } else if (static_lenb == opt_lenb) {
+#endif
+        send_bits((STATIC_TREES<<1)+eof, 3);
+        compress_block((ct_data *)static_ltree, (ct_data *)static_dtree);
+        compressed_len += 3 + static_len;
+    } else {
+        send_bits((DYN_TREES<<1)+eof, 3);
+        send_all_trees(l_desc.max_code+1, d_desc.max_code+1, max_blindex+1);
+        compress_block((ct_data *)dyn_ltree, (ct_data *)dyn_dtree);
+        compressed_len += 3 + opt_len;
+    }
+    Assert (compressed_len == bits_sent, "bad compressed size");
+    init_block();
+
+    if (eof) {
+        Assert (input_len == isize, "bad input size");
+        bi_windup();
+        compressed_len += 7;  /* align on byte boundary */
+    }
+    Tracev((stderr,"\ncomprlen %lu(%lu) ", compressed_len>>3,
+           compressed_len-7*eof));
+
+    return compressed_len >> 3;
+}
+
+/* ===========================================================================
+ * Save the match info and tally the frequency counts. Return true if
+ * the current block must be flushed.
+ */
+int ct_tally (dist, lc)
+    int dist;  /* distance of matched string */
+    int lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
+{
+    l_buf[last_lit++] = (uch)lc;
+    if (dist == 0) {
+        /* lc is the unmatched char */
+        dyn_ltree[lc].Freq++;
+    } else {
+        /* Here, lc is the match length - MIN_MATCH */
+        dist--;             /* dist = match distance - 1 */
+        Assert((ush)dist < (ush)MAX_DIST &&
+               (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
+               (ush)d_code(dist) < (ush)D_CODES,  "ct_tally: bad match");
+
+        dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
+        dyn_dtree[d_code(dist)].Freq++;
+
+        d_buf[last_dist++] = (ush)dist;
+        flags |= flag_bit;
+    }
+    flag_bit <<= 1;
+
+    /* Output the flags if they fill a byte: */
+    if ((last_lit & 7) == 0) {
+        flag_buf[last_flags++] = flags;
+        flags = 0, flag_bit = 1;
+    }
+    /* Try to guess if it is profitable to stop the current block here */
+    if (level > 2 && (last_lit & 0xfff) == 0) {
+        /* Compute an upper bound for the compressed length */
+        ulg out_length = (ulg)last_lit*8L;
+        ulg in_length = (ulg)strstart-block_start;
+        int dcode;
+        for (dcode = 0; dcode < D_CODES; dcode++) {
+            out_length += (ulg)dyn_dtree[dcode].Freq*(5L+extra_dbits[dcode]);
+        }
+        out_length >>= 3;
+        Trace((stderr,"\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ",
+               last_lit, last_dist, in_length, out_length,
+               100L - out_length*100L/in_length));
+        if (last_dist < last_lit/2 && out_length < in_length/2) return 1;
+    }
+    return (last_lit == LIT_BUFSIZE-1 || last_dist == DIST_BUFSIZE);
+    /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K
+     * on 16 bit machines and because stored blocks are restricted to
+     * 64K-1 bytes.
+     */
+}
+
+/* ===========================================================================
+ * Send the block data compressed using the given Huffman trees
+ */
+local void compress_block(ltree, dtree)
+    ct_data *ltree; /* literal tree */
+    ct_data *dtree; /* distance tree */
+{
+    unsigned dist;      /* distance of matched string */
+    int lc;             /* match length or unmatched char (if dist == 0) */
+    unsigned lx = 0;    /* running index in l_buf */
+    unsigned dx = 0;    /* running index in d_buf */
+    unsigned fx = 0;    /* running index in flag_buf */
+    uch flag = 0;       /* current flags */
+    unsigned code;      /* the code to send */
+    int extra;          /* number of extra bits to send */
+
+    if (last_lit != 0) do {
+        if ((lx & 7) == 0) flag = flag_buf[fx++];
+        lc = l_buf[lx++];
+        if ((flag & 1) == 0) {
+            send_code(lc, ltree); /* send a literal byte */
+            Tracecv(isgraph(lc), (stderr," '%c' ", lc));
+        } else {
+            /* Here, lc is the match length - MIN_MATCH */
+            code = length_code[lc];
+            send_code(code+LITERALS+1, ltree); /* send the length code */
+            extra = extra_lbits[code];
+            if (extra != 0) {
+                lc -= base_length[code];
+                send_bits(lc, extra);        /* send the extra length bits */
+            }
+            dist = d_buf[dx++];
+            /* Here, dist is the match distance - 1 */
+            code = d_code(dist);
+            Assert (code < D_CODES, "bad d_code");
+
+            send_code(code, dtree);       /* send the distance code */
+            extra = extra_dbits[code];
+            if (extra != 0) {
+                dist -= base_dist[code];
+                send_bits(dist, extra);   /* send the extra distance bits */
+            }
+        } /* literal or match pair ? */
+        flag >>= 1;
+    } while (lx < last_lit);
+
+    send_code(END_BLOCK, ltree);
+}
+
+/* ===========================================================================
+ * Set the file type to ASCII or BINARY, using a crude approximation:
+ * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
+ * IN assertion: the fields freq of dyn_ltree are set and the total of all
+ * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
+ */
+local void set_file_type()
+{
+    int n = 0;
+    unsigned ascii_freq = 0;
+    unsigned bin_freq = 0;
+    while (n < 7)        bin_freq += dyn_ltree[n++].Freq;
+    while (n < 128)    ascii_freq += dyn_ltree[n++].Freq;
+    while (n < LITERALS) bin_freq += dyn_ltree[n++].Freq;
+    *file_type = bin_freq > (ascii_freq >> 2) ? BINARY : ASCII;
+    if (*file_type == BINARY && translate_eol) {
+        warn("-l used on binary file", "");
+    }
+}
diff --git a/usr/gzip/unzip.c b/usr/gzip/unzip.c
new file mode 100644
index 0000000..c8e14a3
--- /dev/null
+++ b/usr/gzip/unzip.c
@@ -0,0 +1,77 @@
+/* unzip.c -- decompress files in gzip or pkzip format.
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ *
+ * The code in this file is derived from the file funzip.c written
+ * and put in the public domain by Mark Adler.
+ */
+
+/*
+   This version can extract files in gzip format.
+   Only the first entry is extracted, and it has to be
+   either deflated or stored.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: unzip.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+#include "tailor.h"
+#include "gzip.h"
+
+/* ===========================================================================
+ * Unzip in to out.  This routine works on gzip files only.
+ *
+ * IN assertions: the buffer inbuf contains already the beginning of
+ *   the compressed data, from offsets inptr to insize-1 included.
+ *   The magic header has already been checked. The output buffer is cleared.
+ */
+int unzip(in, out)
+    int in, out;   /* input and output file descriptors */
+{
+    ulg orig_crc = 0;       /* original crc */
+    ulg orig_len = 0;       /* original uncompressed length */
+    int n;
+    uch buf[8];        /* extended local header */
+
+    ifd = in;
+    ofd = out;
+
+    updcrc(NULL, 0);           /* initialize crc */
+
+    /* Decompress */
+    if (method == DEFLATED)  {
+
+	int res = inflate();
+
+	if (res == 3) {
+	    error("out of memory");
+	} else if (res != 0) {
+	    error("invalid compressed data--format violated");
+	}
+
+    } else {
+	error("internal error, invalid method");
+    }
+
+    /* Get the crc and original length */
+    /* crc32  (see algorithm.doc)
+     * uncompressed input size modulo 2^32
+     */
+    for (n = 0; n < 8; n++) {
+	buf[n] = (uch)get_byte(); /* may cause an error if EOF */
+    }
+    orig_crc = LG(buf);
+    orig_len = LG(buf+4);
+
+    /* Validate decompression */
+    if (orig_crc != updcrc(outbuf, 0)) {
+	error("invalid compressed data--crc error");
+    }
+    if (orig_len != (ulg)bytes_out) {
+	error("invalid compressed data--length error");
+    }
+
+    return OK;
+}
diff --git a/usr/gzip/util.c b/usr/gzip/util.c
new file mode 100644
index 0000000..22ff6e5
--- /dev/null
+++ b/usr/gzip/util.c
@@ -0,0 +1,372 @@
+/* util.c -- utility functions for gzip support
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: util.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+#include <ctype.h>
+#include <errno.h>
+#include <sys/types.h>
+
+#include "tailor.h"
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+
+#include "gzip.h"
+
+extern ulg crc_32_tab[];   /* crc table, defined below */
+
+/* ===========================================================================
+ * Copy input to output unchanged: zcat == cat with --force.
+ * IN assertion: insize bytes have already been read in inbuf.
+ */
+int copy(in, out)
+    int in, out;   /* input and output file descriptors */
+{
+    errno = 0;
+    while (insize != 0 && (int)insize != EOF) {
+	write_buf(out, (char*)inbuf, insize);
+	bytes_out += insize;
+	insize = read(in, (char*)inbuf, INBUFSIZ);
+    }
+    if ((int)insize == EOF && errno != 0) {
+	read_error();
+    }
+    bytes_in = bytes_out;
+    return OK;
+}
+
+/* ===========================================================================
+ * Run a set of bytes through the crc shift register.  If s is a NULL
+ * pointer, then initialize the crc shift register contents instead.
+ * Return the current crc in either case.
+ */
+ulg updcrc(s, n)
+    uch *s;                 /* pointer to bytes to pump through */
+    unsigned n;             /* number of bytes in s[] */
+{
+    register ulg c;         /* temporary variable */
+
+    static ulg crc = (ulg)0xffffffffL; /* shift register contents */
+
+    if (s == NULL) {
+	c = 0xffffffffL;
+    } else {
+	c = crc;
+        if (n) do {
+            c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
+        } while (--n);
+    }
+    crc = c;
+    return c ^ 0xffffffffL;       /* (instead of ~c for 64-bit machines) */
+}
+
+/* ===========================================================================
+ * Clear input and output buffers
+ */
+void clear_bufs()
+{
+    outcnt = 0;
+    insize = inptr = 0;
+    bytes_in = bytes_out = 0L;
+}
+
+/* ===========================================================================
+ * Fill the input buffer. This is called only when the buffer is empty.
+ */
+int fill_inbuf(eof_ok)
+    int eof_ok;          /* set if EOF acceptable as a result */
+{
+    int len;
+
+    /* Read as much as possible */
+    insize = 0;
+    errno = 0;
+    do {
+	len = read(ifd, (char*)inbuf+insize, INBUFSIZ-insize);
+        if (len == 0 || len == EOF) break;
+	insize += len;
+    } while (insize < INBUFSIZ);
+
+    if (insize == 0) {
+	if (eof_ok) return EOF;
+	read_error();
+    }
+    bytes_in += (ulg)insize;
+    inptr = 1;
+    return inbuf[0];
+}
+
+/* ===========================================================================
+ * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
+ * (used for the compressed data only)
+ */
+void flush_outbuf()
+{
+    if (outcnt == 0) return;
+
+    write_buf(ofd, (char *)outbuf, outcnt);
+    bytes_out += (ulg)outcnt;
+    outcnt = 0;
+}
+
+/* ===========================================================================
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+void flush_window()
+{
+    if (outcnt == 0) return;
+    updcrc(window, outcnt);
+
+    if (!test) {
+	write_buf(ofd, (char *)window, outcnt);
+    }
+    bytes_out += (ulg)outcnt;
+    outcnt = 0;
+}
+
+/* ===========================================================================
+ * Does the same as write(), but also handles partial pipe writes and checks
+ * for error return.
+ */
+void write_buf(fd, buf, cnt)
+    int       fd;
+    voidp     buf;
+    unsigned  cnt;
+{
+    unsigned  n;
+
+    while ((n = write(fd, buf, cnt)) != cnt) {
+	if (n == (unsigned)(-1)) {
+	    write_error();
+	}
+	cnt -= n;
+	buf = (voidp)((char*)buf+n);
+    }
+}
+
+/* ========================================================================
+ * Put string s in lower case, return s.
+ */
+char *strlwr(s)
+    char *s;
+{
+    char *t;
+    for (t = s; *t; t++) *t = tolow(*t);
+    return s;
+}
+
+/* ========================================================================
+ * Return the base name of a file (remove any directory prefix and
+ * any version suffix). For systems with file names that are not
+ * case sensitive, force the base name to lower case.
+ */
+char *basename(fname)
+    char *fname;
+{
+    char *p;
+
+    if ((p = strrchr(fname, PATH_SEP))  != NULL) fname = p+1;
+    if (casemap('A') == 'a') strlwr(fname);
+    return fname;
+}
+
+/* ========================================================================
+ * Add an environment variable (if any) before argv, and update argc.
+ * Return the expanded environment variable to be freed later, or NULL
+ * if no options were added to argv.
+ */
+#define SEPARATOR	" \t"	/* separators in env variable */
+
+char *add_envopt(argcp, argvp, env)
+    int *argcp;          /* pointer to argc */
+    char ***argvp;       /* pointer to argv */
+    char *env;           /* name of environment variable */
+{
+    char *p;             /* running pointer through env variable */
+    char **oargv;        /* runs through old argv array */
+    char **nargv;        /* runs through new argv array */
+    int	 oargc = *argcp; /* old argc */
+    int  nargc = 0;      /* number of arguments in env variable */
+
+    env = (char*)getenv(env);
+    if (env == NULL) return NULL;
+
+    p = (char*)xmalloc(strlen(env)+1);
+    env = strcpy(p, env);                    /* keep env variable intact */
+
+    for (p = env; *p; nargc++ ) {            /* move through env */
+	p += strspn(p, SEPARATOR);	     /* skip leading separators */
+	if (*p == '\0') break;
+
+	p += strcspn(p, SEPARATOR);	     /* find end of word */
+	if (*p) *p++ = '\0';		     /* mark it */
+    }
+    if (nargc == 0) {
+	free(env);
+	return NULL;
+    }
+    *argcp += nargc;
+    /* Allocate the new argv array, with an extra element just in case
+     * the original arg list did not end with a NULL.
+     */
+    nargv = (char**)calloc(*argcp+1, sizeof(char *));
+    if (nargv == NULL) error("out of memory");
+    oargv  = *argvp;
+    *argvp = nargv;
+
+    /* Copy the program name first */
+    if (oargc-- < 0) error("argc<=0");
+    *(nargv++) = *(oargv++);
+
+    /* Then copy the environment args */
+    for (p = env; nargc > 0; nargc--) {
+	p += strspn(p, SEPARATOR);	     /* skip separators */
+	*(nargv++) = p;			     /* store start */
+	while (*p++) ;			     /* skip over word */
+    }
+
+    /* Finally copy the old args and add a NULL (usual convention) */
+    while (oargc--) *(nargv++) = *(oargv++);
+    *nargv = NULL;
+    return env;
+}
+
+/* ========================================================================
+ * Error handlers.
+ */
+void error(m)
+    char *m;
+{
+    fprintf(stderr, "\n%s: %s: %s\n", progname, ifname, m);
+    abort_gzip();
+}
+
+void warn(a, b)
+    char *a, *b;            /* message strings juxtaposed in output */
+{
+    WARN((stderr, "%s: %s: warning: %s%s\n", progname, ifname, a, b));
+}
+
+void read_error()
+{
+    fprintf(stderr, "\n%s: ", progname);
+    if (errno != 0) {
+	perror(ifname);
+    } else {
+	fprintf(stderr, "%s: unexpected end of file\n", ifname);
+    }
+    abort_gzip();
+}
+
+void write_error()
+{
+    fprintf(stderr, "\n%s: ", progname);
+    perror(ofname);
+    abort_gzip();
+}
+
+/* ========================================================================
+ * Display compression ratio on the given stream on 6 characters.
+ */
+void display_ratio(num, den, file)
+    long num;
+    long den;
+    FILE *file;
+{
+    long ratio;  /* 1000 times the compression ratio */
+    char sign;
+
+    if (den == 0) {
+	ratio = 0; /* no compression */
+    } else if (den < 2147483L) { /* (2**31 -1)/1000 */
+	ratio = 1000L*num/den;
+    } else {
+	ratio = num/(den/1000L);
+    }
+    if (ratio < 0) {
+	sign = '-';
+	ratio = -ratio;
+    } else {
+	sign = ' ';
+    }
+    fprintf(file, "%c%2ld.%1ld%%", sign, ratio / 10L, ratio % 10L);
+}
+
+
+/* ========================================================================
+ * Semi-safe malloc -- never returns NULL.
+ */
+voidp xmalloc (size)
+    unsigned size;
+{
+    voidp cp = (voidp)malloc (size);
+
+    if (cp == NULL) error("out of memory");
+    return cp;
+}
+
+/* ========================================================================
+ * Table of CRC-32's of all single-byte values (made by makecrc.c)
+ */
+ulg crc_32_tab[] = {
+  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
+  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
+  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
+  0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
+  0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
+  0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
+  0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
+  0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
+  0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
+  0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
+  0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
+  0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
+  0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
+  0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
+  0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
+  0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
+  0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
+  0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
+  0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
+  0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
+  0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
+  0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
+  0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
+  0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
+  0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
+  0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
+  0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
+  0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
+  0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
+  0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
+  0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
+  0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
+  0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
+  0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
+  0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
+  0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
+  0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
+  0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
+  0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
+  0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
+  0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
+  0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
+  0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
+  0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
+  0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
+  0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
+  0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
+  0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
+  0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
+  0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
+  0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
+  0x2d02ef8dL
+};
diff --git a/usr/gzip/zip.c b/usr/gzip/zip.c
new file mode 100644
index 0000000..d0394c2
--- /dev/null
+++ b/usr/gzip/zip.c
@@ -0,0 +1,110 @@
+/* zip.c -- compress files to the gzip or pkzip format
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: zip.c,v 1.1 2002/08/18 00:59:21 hpa Exp $";
+#endif
+
+#include <ctype.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "tailor.h"
+#include "gzip.h"
+
+local ulg crc;       /* crc on uncompressed file data */
+
+/* ===========================================================================
+ * Deflate in to out.
+ * IN assertions: the input and output buffers are cleared.
+ *   The variables time_stamp and save_orig_name are initialized.
+ */
+int zip(in, out)
+    int in, out;            /* input and output file descriptors */
+{
+    uch  flags = 0;         /* general purpose bit flags */
+    ush  attr = 0;          /* ascii/binary flag */
+    ush  deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */
+
+    ifd = in;
+    ofd = out;
+    outcnt = 0;
+
+    /* Write the header to the gzip file. See algorithm.doc for the format */
+
+    method = DEFLATED;
+    put_byte(GZIP_MAGIC[0]); /* magic header */
+    put_byte(GZIP_MAGIC[1]);
+    put_byte(DEFLATED);      /* compression method */
+
+    if (save_orig_name) {
+	flags |= ORIG_NAME;
+    }
+    put_byte(flags);         /* general flags */
+    put_long(time_stamp);
+
+    /* Write deflated file to zip file */
+    crc = updcrc(0, 0);
+
+    bi_init(out);
+    ct_init(&attr, &method);
+    lm_init(level, &deflate_flags);
+
+    put_byte((uch)deflate_flags); /* extra flags */
+    put_byte(OS_CODE);            /* OS identifier */
+
+    if (save_orig_name) {
+	char *p = basename(ifname); /* Don't save the directory part. */
+	do {
+	    put_char(*p);
+	} while (*p++);
+    }
+    header_bytes = (long)outcnt;
+
+    (void)deflate();
+
+#if !defined(NO_SIZE_CHECK) && !defined(RECORD_IO)
+  /* Check input size (but not in VMS -- variable record lengths mess it up)
+   * and not on MSDOS -- diet in TSR mode reports an incorrect file size)
+   */
+    if (ifile_size != -1L && isize != (ulg)ifile_size) {
+	Trace((stderr, " actual=%ld, read=%ld ", ifile_size, isize));
+	fprintf(stderr, "%s: %s: file size changed while zipping\n",
+		progname, ifname);
+    }
+#endif
+
+    /* Write the crc and uncompressed size */
+    put_long(crc);
+    put_long(isize);
+    header_bytes += 2*sizeof(long);
+
+    flush_outbuf();
+    return OK;
+}
+
+
+/* ===========================================================================
+ * Read a new buffer from the current input file, perform end-of-line
+ * translation, and update the crc and input file size.
+ * IN assertion: size >= 2 (for end-of-line translation)
+ */
+int file_read(buf, size)
+    char *buf;
+    unsigned size;
+{
+    unsigned len;
+
+    Assert(insize == 0, "inbuf not empty");
+
+    len = read(ifd, buf, size);
+    if (len == (unsigned)(-1) || len == 0) return (int)len;
+
+    crc = updcrc((uch*)buf, len);
+    isize += (ulg)len;
+    return (int)len;
+}