blob: 49877322f33619314c065879813de8854be35264 [file] [log] [blame]
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1997-2005
* Herbert Xu <herbert@gondor.apana.org.au>. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <stdio.h> /* defines BUFSIZ */
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
/*
* This file implements the input routines used by the parser.
*/
#include "eval.h"
#include "shell.h"
#include "redir.h"
#include "syntax.h"
#include "input.h"
#include "output.h"
#include "options.h"
#include "memalloc.h"
#include "error.h"
#include "alias.h"
#include "parser.h"
#include "main.h"
#ifndef SMALL
#include "myhistedit.h"
#endif
#define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */
#define IBUFSIZ (BUFSIZ + 1)
MKINIT struct parsefile basepf; /* top level input file */
MKINIT char basebuf[IBUFSIZ]; /* buffer for top level input file */
struct parsefile *parsefile = &basepf; /* current input file */
int whichprompt; /* 1 == PS1, 2 == PS2 */
STATIC void pushfile(void);
static void popstring(void);
static int preadfd(void);
static void setinputfd(int fd, int push);
static int preadbuffer(void);
#ifdef mkinit
INCLUDE <stdio.h>
INCLUDE <unistd.h>
INCLUDE "input.h"
INCLUDE "error.h"
INIT {
basepf.nextc = basepf.buf = basebuf;
basepf.linno = 1;
}
RESET {
/* clear input buffer */
basepf.lleft = basepf.nleft = 0;
popallfiles();
}
FORKRESET {
popallfiles();
if (parsefile->fd > 0) {
close(parsefile->fd);
parsefile->fd = 0;
}
}
#endif
static void freestrings(struct strpush *sp)
{
INTOFF;
do {
struct strpush *psp;
if (sp->ap) {
sp->ap->flag &= ~ALIASINUSE;
if (sp->ap->flag & ALIASDEAD) {
unalias(sp->ap->name);
}
}
psp = sp;
sp = sp->spfree;
if (psp != &(parsefile->basestrpush))
ckfree(psp);
} while (sp);
parsefile->spfree = NULL;
INTON;
}
static int __pgetc(void)
{
int c;
if (parsefile->unget)
return parsefile->lastc[--parsefile->unget];
if (--parsefile->nleft >= 0)
c = (signed char)*parsefile->nextc++;
else
c = preadbuffer();
parsefile->lastc[1] = parsefile->lastc[0];
parsefile->lastc[0] = c;
return c;
}
/*
* Read a character from the script, returning PEOF on end of file.
* Nul characters in the input are silently discarded.
*/
int pgetc(void)
{
struct strpush *sp = parsefile->spfree;
if (unlikely(sp))
freestrings(sp);
return __pgetc();
}
static int
preadfd(void)
{
int nr;
char *buf = parsefile->buf;
parsefile->nextc = buf;
retry:
#ifndef SMALL
if (parsefile->fd == 0 && el) {
static const char *rl_cp;
static int el_len;
if (rl_cp == NULL) {
struct stackmark smark;
pushstackmark(&smark, stackblocksize());
rl_cp = el_gets(el, &el_len);
popstackmark(&smark);
}
if (rl_cp == NULL)
nr = 0;
else {
nr = el_len;
if (nr > IBUFSIZ - 1)
nr = IBUFSIZ - 1;
memcpy(buf, rl_cp, nr);
if (nr != el_len) {
el_len -= nr;
rl_cp += nr;
} else
rl_cp = 0;
}
} else
#endif
nr = read(parsefile->fd, buf, IBUFSIZ - 1);
if (nr < 0) {
if (errno == EINTR)
goto retry;
if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
int flags = fcntl(0, F_GETFL, 0);
if (flags >= 0 && flags & O_NONBLOCK) {
flags &=~ O_NONBLOCK;
if (fcntl(0, F_SETFL, flags) >= 0) {
out2str("sh: turning off NDELAY mode\n");
goto retry;
}
}
}
}
return nr;
}
/*
* Refill the input buffer and return the next input character:
*
* 1) If a string was pushed back on the input, pop it;
* 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
* from a string so we can't refill the buffer, return EOF.
* 3) If the is more stuff in this buffer, use it else call read to fill it.
* 4) Process input up to the next newline, deleting nul characters.
*/
static int preadbuffer(void)
{
char *q;
int more;
#ifndef SMALL
int something;
#endif
char savec;
if (unlikely(parsefile->strpush)) {
popstring();
return __pgetc();
}
if (unlikely(parsefile->nleft == EOF_NLEFT ||
parsefile->buf == NULL))
return PEOF;
flushall();
more = parsefile->lleft;
if (more <= 0) {
again:
if ((more = preadfd()) <= 0) {
parsefile->lleft = parsefile->nleft = EOF_NLEFT;
return PEOF;
}
}
q = parsefile->nextc;
/* delete nul characters */
#ifndef SMALL
something = 0;
#endif
for (;;) {
int c;
more--;
c = *q;
if (!c)
memmove(q, q + 1, more);
else {
q++;
if (c == '\n') {
parsefile->nleft = q - parsefile->nextc - 1;
break;
}
#ifndef SMALL
switch (c) {
default:
something = 1;
/* fall through */
case '\t':
case ' ':
break;
}
#endif
}
if (more <= 0) {
parsefile->nleft = q - parsefile->nextc - 1;
if (parsefile->nleft < 0)
goto again;
break;
}
}
parsefile->lleft = more;
savec = *q;
*q = '\0';
#ifndef SMALL
if (parsefile->fd == 0 && hist && something) {
HistEvent he;
INTOFF;
history(hist, &he, whichprompt == 1? H_ENTER : H_APPEND,
parsefile->nextc);
INTON;
}
#endif
if (vflag) {
out2str(parsefile->nextc);
#ifdef FLUSHERR
flushout(out2);
#endif
}
*q = savec;
return (signed char)*parsefile->nextc++;
}
/*
* Undo a call to pgetc. Only two characters may be pushed back.
* PEOF may be pushed back.
*/
void
pungetc(void)
{
parsefile->unget++;
}
/*
* Push a string back onto the input at this current parsefile level.
* We handle aliases this way.
*/
void
pushstring(char *s, void *ap)
{
struct strpush *sp;
size_t len;
len = strlen(s);
INTOFF;
/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/
if ((unsigned long)parsefile->strpush |
(unsigned long)parsefile->spfree) {
sp = ckmalloc(sizeof (struct strpush));
sp->prev = parsefile->strpush;
parsefile->strpush = sp;
} else
sp = parsefile->strpush = &(parsefile->basestrpush);
sp->prevstring = parsefile->nextc;
sp->prevnleft = parsefile->nleft;
sp->unget = parsefile->unget;
sp->spfree = parsefile->spfree;
memcpy(sp->lastc, parsefile->lastc, sizeof(sp->lastc));
sp->ap = (struct alias *)ap;
if (ap) {
((struct alias *)ap)->flag |= ALIASINUSE;
sp->string = s;
}
parsefile->nextc = s;
parsefile->nleft = len;
parsefile->unget = 0;
parsefile->spfree = NULL;
INTON;
}
static void popstring(void)
{
struct strpush *sp = parsefile->strpush;
INTOFF;
if (sp->ap) {
if (parsefile->nextc[-1] == ' ' ||
parsefile->nextc[-1] == '\t') {
checkkwd |= CHKALIAS;
}
if (sp->string != sp->ap->val) {
ckfree(sp->string);
}
}
parsefile->nextc = sp->prevstring;
parsefile->nleft = sp->prevnleft;
parsefile->unget = sp->unget;
memcpy(parsefile->lastc, sp->lastc, sizeof(sp->lastc));
/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/
parsefile->strpush = sp->prev;
parsefile->spfree = sp;
INTON;
}
/*
* Set the input to take input from a file. If push is set, push the
* old input onto the stack first.
*/
int
setinputfile(const char *fname, int flags)
{
int fd;
INTOFF;
fd = sh_open(fname, O_RDONLY, flags & INPUT_NOFILE_OK);
if (fd < 0)
goto out;
if (fd < 10)
fd = savefd(fd, fd);
setinputfd(fd, flags & INPUT_PUSH_FILE);
out:
INTON;
return fd;
}
/*
* Like setinputfile, but takes an open file descriptor. Call this with
* interrupts off.
*/
static void
setinputfd(int fd, int push)
{
if (push) {
pushfile();
parsefile->buf = 0;
}
parsefile->fd = fd;
if (parsefile->buf == NULL)
parsefile->buf = ckmalloc(IBUFSIZ);
parsefile->lleft = parsefile->nleft = 0;
plinno = 1;
}
/*
* Like setinputfile, but takes input from a string.
*/
void
setinputstring(char *string)
{
INTOFF;
pushfile();
parsefile->nextc = string;
parsefile->nleft = strlen(string);
parsefile->buf = NULL;
plinno = 1;
INTON;
}
/*
* To handle the "." command, a stack of input files is used. Pushfile
* adds a new entry to the stack and popfile restores the previous level.
*/
STATIC void
pushfile(void)
{
struct parsefile *pf;
pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
pf->prev = parsefile;
pf->fd = -1;
pf->strpush = NULL;
pf->spfree = NULL;
pf->basestrpush.prev = NULL;
pf->unget = 0;
parsefile = pf;
}
void
popfile(void)
{
struct parsefile *pf = parsefile;
INTOFF;
if (pf->fd >= 0)
close(pf->fd);
if (pf->buf)
ckfree(pf->buf);
if (parsefile->spfree)
freestrings(parsefile->spfree);
while (pf->strpush) {
popstring();
freestrings(parsefile->spfree);
}
parsefile = pf->prev;
ckfree(pf);
INTON;
}
void unwindfiles(struct parsefile *stop)
{
while (parsefile != stop)
popfile();
}
/*
* Return to top level.
*/
void
popallfiles(void)
{
unwindfiles(&basepf);
}