Здравствуйте.
Есть несколько файлов упакованных zlib.
На забугорном форуме нашел код, как мне кажется для упаковки распаковки, а как и что с ним делать, не хватает серого вещества.
Помогите пожалуйста.
Как сделать с помощью этого какую-нибудь утилитку, которая будет распаковывать запакованные файлы?
| Код |
/* zpipe.c: example of proper use of zlib's inflate() and deflate()
Not copyrighted -- provided to the public domain
Version 1.2 9 November 2004 Mark Adler */
/* Version history:
1.0 30 Oct 2004 First version
1.1 8 Nov 2004 Add void casting for unused return values
Use switch statement for inflate() return values
1.2 9 Nov 2004 Add assertions to document zlib guarantees
1.3 6 Apr 2005 Remove incorrect assertion in inf()
*/
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "zlib.h"
#include <sys/types.h>
#include <sys/stat.h>
#define CHUNK 16384
/* Compress from file source to file dest until EOF on source.
def() returns Z_OK on success, Z_MEM_ERROR if memory could not be
allocated for processing, Z_STREAM_ERROR if an invalid compression
level is supplied, Z_VERSION_ERROR if the version of zlib.h and the
version of the library linked do not match, or Z_ERRNO if there is
an error reading or writing the files. */
int def(FILE *source, FILE *dest, int level)
{
int ret, flush;
unsigned have;
z_stream strm;
char in[CHUNK];
char out[CHUNK];
char *buf;
unsigned long dest_size;
unsigned long indx = 0;
struct stat sb;
have = fileno(source);
if (fstat(have, &sb) < 0)
return Z_ERRNO;
if (!S_ISREG(sb.st_mode))
return Z_ERRNO;
if ((dest_size = (unsigned long)sb.st_size) <= 0)
return Z_ERRNO;
if (fwrite(&dest_size, 4, 1, dest) != 1 || ferror(dest))
return Z_ERRNO;
/* allocate deflate state */
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
ret = deflateInit2(&strm, level, Z_DEFLATED, -MAX_WBITS, 8, Z_DEFAULT_STRATEGY);
if (ret != Z_OK)
return ret;
/* compress until end of file */
do {
strm.avail_in = fread(in, 1, CHUNK, source);
if (ferror(source)) {
(void)deflateEnd(&strm);
return Z_ERRNO;
}
flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
strm.next_in = in;
/* run deflate() on input until output buffer not full, finish
compression if all of source has been read in */
do {
strm.avail_out = CHUNK;
strm.next_out = out;
ret = deflate(&strm, flush); /* no bad return value */
assert(ret != Z_STREAM_ERROR); /* state not clobbered */
have = CHUNK - strm.avail_out;
if (have > 0) {
buf = out;
do {
if (dest_size > indx++) {
switch (indx) {
case 1:
*buf ^= 0x92;
break;
case 2:
*buf ^= 0x65;
break;
case 3:
*buf ^= 0x67;
break;
case 4:
*buf ^= 0x57;
}
}
} while (*buf++);
if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
(void)deflateEnd(&strm);
return Z_ERRNO;
}
}
} while (strm.avail_out == 0);
assert(strm.avail_in == 0); /* all input will be used */
/* done when last data in file processed */
} while (flush != Z_FINISH);
assert(ret == Z_STREAM_END); /* stream will be complete */
/* clean up and return */
(void)deflateEnd(&strm);
return Z_OK;
}
/* Decompress from file source to file dest until stream ends or EOF.
inf() returns Z_OK on success, Z_MEM_ERROR if memory could not be
allocated for processing, Z_DATA_ERROR if the deflate data is
invalid or incomplete, Z_VERSION_ERROR if the version of zlib.h and
the version of the library linked do not match, or Z_ERRNO if there
is an error reading or writing the files. */
int inf(FILE *source, FILE *dest)
{
int ret;
unsigned have;
z_stream strm;
char in[CHUNK];
char out[CHUNK];
char *buf;
unsigned long dest_size;
unsigned long indx = 0;
have = fread(in, 1, 4, source);
if (have != 4 || ferror(source)) {
return Z_ERRNO;
}
dest_size = ((unsigned long)in[0]) |
((unsigned long)in[1] << 8) |
((unsigned long)in[2] << 16) |
((unsigned long)in[3] << 24);
/* 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, -MAX_WBITS);
if (ret != Z_OK)
return ret;
/* decompress until deflate stream ends or end of file */
do {
strm.avail_in = fread(in, 1, CHUNK, source);
if (ferror(source)) {
(void)inflateEnd(&strm);
return Z_ERRNO;
}
if (strm.avail_in == 0)
break;
buf = in;
do {
if (dest_size > indx++) {
switch (indx) {
case 1:
*buf ^= 0x92;
break;
case 2:
*buf ^= 0x65;
break;
case 3:
*buf ^= 0x67;
break;
case 4:
*buf ^= 0x57;
}
}
} while (*buf++);
strm.next_in = in;
/* run inflate() on input until output buffer not full */
do {
strm.avail_out = CHUNK;
strm.next_out = out;
ret = inflate(&strm, Z_NO_FLUSH);
assert(ret != Z_STREAM_ERROR); /* state not clobbered */
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;
if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
(void)inflateEnd(&strm);
return Z_ERRNO;
}
} 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;
}
/* report a zlib or i/o error */
void zerr(int ret)
{
fputs("zpipe: ", stderr);
switch (ret) {
case Z_ERRNO:
if (ferror(stdin))
fputs("error reading stdin\n", stderr);
if (ferror(stdout))
fputs("error writing stdout\n", stderr);
break;
case Z_STREAM_ERROR:
fputs("invalid compression level\n", stderr);
break;
case Z_DATA_ERROR:
fputs("invalid or incomplete deflate data\n", stderr);
break;
case Z_MEM_ERROR:
fputs("out of memory\n", stderr);
break;
case Z_VERSION_ERROR:
fputs("zlib version mismatch!\n", stderr);
}
}
/* compress or decompress from stdin to stdout */
int main(int argc, char **argv)
{
int ret;
/* do compression if -c specified */
if (argc == 2 && strcmp(argv[1], "-c") == 0) {
ret = def(stdin, stdout, Z_DEFAULT_COMPRESSION);
if (ret != Z_OK)
zerr(ret);
return ret;
}
/* do decompression if -d specified */
else if (argc == 2 && strcmp(argv[1], "-d") == 0) {
ret = inf(stdin, stdout);
if (ret != Z_OK)
zerr(ret);
return ret;
}
/* otherwise, report usage */
else {
fputs("encpack usage: encpack [-c|-d] < source > dest\n", stderr);
fputs("E.g: encpack -c < file.txt > file.enc\n\n", stderr);
return 1;
}
}
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Известно точно, что файлы изначально текстовые. В упакованном виде имеют расширение *.enc
Расскажите, куда что вставлять, что нажимать. |
