blob: f4a30e564c8bca79a0f00cd9920f3ad22c8f7549 [file] [log] [blame]
/*
Copyright (C) 2008 Arnaldo Carvalho de Melo <acme@redhat.com>
Grow only buffer, add entries but never delete
This program is free software; you can redistribute it and/or modify it
under the terms of version 2 of the GNU General Public License as
published by the Free Software Foundation.
*/
#include "gobuffer.h"
#include <search.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <zlib.h>
#include <errno.h>
#include "dutil.h"
#define GOBUFFER__BCHUNK (8 * 1024)
#define GOBUFFER__ZCHUNK (8 * 1024)
void gobuffer__init(struct gobuffer *self)
{
self->entries = NULL;
self->nr_entries = self->allocated_size = 0;
/* 0 == NULL */
self->index = 1;
}
struct gobuffer *gobuffer__new(void)
{
struct gobuffer *self = malloc(sizeof(*self));
if (self != NULL)
gobuffer__init(self);
return self;
}
void __gobuffer__delete(struct gobuffer *self)
{
free(self->entries);
}
void gobuffer__delete(struct gobuffer *self)
{
__gobuffer__delete(self);
free(self);
}
void *gobuffer__ptr(const struct gobuffer *self, unsigned int s)
{
return s ? self->entries + s : NULL;
}
int gobuffer__allocate(struct gobuffer *self, unsigned int len)
{
const unsigned int rc = self->index;
const unsigned int index = self->index + len;
if (index >= self->allocated_size) {
unsigned int allocated_size = (self->allocated_size +
GOBUFFER__BCHUNK);
if (allocated_size < index)
allocated_size = index + GOBUFFER__BCHUNK;
char *entries = realloc(self->entries, allocated_size);
if (entries == NULL)
return -ENOMEM;
self->allocated_size = allocated_size;
self->entries = entries;
}
self->index = index;
return rc;
}
int gobuffer__add(struct gobuffer *self, const void *s, unsigned int len)
{
const int rc = gobuffer__allocate(self, len);
if (rc >= 0) {
++self->nr_entries;
memcpy(self->entries + rc, s, len);
}
return rc;
}
void gobuffer__copy(const struct gobuffer *self, void *dest)
{
memcpy(dest, self->entries, gobuffer__size(self));
}
const void *gobuffer__compress(struct gobuffer *self, unsigned int *size)
{
z_stream z = {
.zalloc = Z_NULL,
.zfree = Z_NULL,
.opaque = Z_NULL,
.avail_in = gobuffer__size(self),
.next_in = (Bytef *)gobuffer__entries(self),
};
void *bf = NULL;
unsigned int bf_size = 0;
if (deflateInit(&z, Z_BEST_COMPRESSION) != Z_OK)
goto out_free;
do {
const unsigned int new_bf_size = bf_size + GOBUFFER__ZCHUNK;
void *nbf = realloc(bf, new_bf_size);
if (nbf == NULL)
goto out_close_and_free;
bf = nbf;
z.avail_out = GOBUFFER__ZCHUNK;
z.next_out = (Bytef *)bf + bf_size;
bf_size = new_bf_size;
if (deflate(&z, Z_FINISH) == Z_STREAM_ERROR)
goto out_close_and_free;
} while (z.avail_out == 0);
deflateEnd(&z);
*size = bf_size - z.avail_out;
out:
return bf;
out_close_and_free:
deflateEnd(&z);
out_free:
free(bf);
bf = NULL;
goto out;
}