pupy/client/sources-linux/decompress.c

69 lines
1.7 KiB
C

#include <zlib.h>
#include "decompress.h"
/* Zpipe code */
#define CHUNK 8196
int decompress(int fd, const char *buf, size_t size) {
int ret;
unsigned have;
z_stream strm;
unsigned char out[CHUNK];
/* allocate inflate state */
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
strm.avail_in = 0;
strm.next_in = Z_NULL;
ret = inflateInit2(&strm, 15+32);
if (ret != Z_OK)
return ret;
/* decompress until deflate stream ends or end of file */
do {
strm.avail_in = size < CHUNK? size : CHUNK;
if (strm.avail_in == 0)
break;
strm.next_in = (unsigned char *) buf;
buf += strm.avail_in;
size -= strm.avail_in;
do {
strm.avail_out = CHUNK;
strm.next_out = out;
ret = inflate(&strm, Z_NO_FLUSH);
switch (ret) {
case Z_NEED_DICT:
ret = Z_DATA_ERROR; /* and fall through */
case Z_DATA_ERROR:
case Z_MEM_ERROR:
(void)inflateEnd(&strm);
return ret;
}
have = CHUNK - strm.avail_out;
unsigned char *ptr = out;
while (have) {
int n = write(fd, ptr, have);
if (n == -1) {
(void)inflateEnd(&strm);
return Z_ERRNO;
}
have -= n;
ptr += n;
}
} while (strm.avail_out == 0);
/* done when inflate() says it's done */
} while (ret != Z_STREAM_END);
/* clean up and return */
(void)inflateEnd(&strm);
return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
}