openssl/crypto/comp/c_zlib.c
1998-12-21 11:00:56 +00:00

144 lines
2.6 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "objects.h"
#include "comp.h"
COMP_METHOD *COMP_zlib(void );
#ifndef ZLIB
static COMP_METHOD zlib_method={
NID_undef,
"(null)",
NULL,
NULL,
NULL,
NULL,
NULL,
};
#else
#include <zlib.h>
static int zlib_compress_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static int zlib_expand_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static int zz_uncompress(Bytef *dest, uLongf *destLen, const Bytef *source,
uLong sourceLen);
static COMP_METHOD zlib_method={
NID_zlib_compression,
LN_zlib_compression,
NULL,
NULL,
zlib_compress_block,
zlib_expand_block,
NULL,
};
static int zlib_compress_block(ctx,out,olen,in,ilen)
COMP_CTX *ctx;
unsigned char *out;
unsigned int olen;
unsigned char *in;
unsigned int ilen;
{
unsigned long l;
int i;
int clear=1;
if (ilen > 128)
{
out[0]=1;
l=olen-1;
i=compress(&(out[1]),&l,in,(unsigned long)ilen);
if (i != Z_OK)
return(-1);
if (ilen > l)
{
clear=0;
l++;
}
}
if (clear)
{
out[0]=0;
memcpy(&(out[1]),in,ilen);
l=ilen+1;
}
fprintf(stderr,"compress(%4d)->%4d %s\n",ilen,(int)l,(clear)?"clear":"zlib");
return((int)l);
}
static int zlib_expand_block(ctx,out,olen,in,ilen)
COMP_CTX *ctx;
unsigned char *out;
unsigned int olen;
unsigned char *in;
unsigned int ilen;
{
unsigned long l;
int i;
if (in[0])
{
l=olen;
i=zz_uncompress(out,&l,&(in[1]),(unsigned long)ilen-1);
if (i != Z_OK)
return(-1);
}
else
{
memcpy(out,&(in[1]),ilen-1);
l=ilen-1;
}
fprintf(stderr,"expand (%4d)->%4d %s\n",ilen,(int)l,in[0]?"zlib":"clear");
return((int)l);
}
static int zz_uncompress (dest, destLen, source, sourceLen)
Bytef *dest;
uLongf *destLen;
const Bytef *source;
uLong sourceLen;
{
z_stream stream;
int err;
stream.next_in = (Bytef*)source;
stream.avail_in = (uInt)sourceLen;
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
stream.next_out = dest;
stream.avail_out = (uInt)*destLen;
if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
stream.zalloc = (alloc_func)0;
stream.zfree = (free_func)0;
err = inflateInit(&stream);
if (err != Z_OK) return err;
err = inflate(&stream, Z_FINISH);
if (err != Z_STREAM_END) {
inflateEnd(&stream);
return err;
}
*destLen = stream.total_out;
err = inflateEnd(&stream);
return err;
}
#endif
COMP_METHOD *COMP_zlib()
{
return(&zlib_method);
}