misc/piggyback/zpipe.c

/* 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
 */

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "zlib.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];

    /* allocate deflate state */
    strm.zalloc = Z_NULL;
    strm.zfree = Z_NULL;
    strm.opaque = Z_NULL;
    ret = deflateInit(&strm, level);
    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 (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];

    /* 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 = inflateInit(&strm);
    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;
        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);
        assert(strm.avail_in == 0);     /* all input will be used */

        /* 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);
    }
}
1	/* zpipe.c: example of proper use of zlib's inflate() and deflate()
2	Not copyrighted -- provided to the public domain
3	Version 1.2 9 November 2004 Mark Adler */
4
5	/* Version history:
6	1.0 30 Oct 2004 First version
7	1.1 8 Nov 2004 Add void casting for unused return values
8	Use switch statement for inflate() return values
9	1.2 9 Nov 2004 Add assertions to document zlib guarantees
10	*/
11
12	#include <stdio.h>
13	#include <string.h>
14	#include <assert.h>
15	#include "zlib.h"
16
17	#define CHUNK 16384
18
19	/* Compress from file source to file dest until EOF on source.
20	def() returns Z_OK on success, Z_MEM_ERROR if memory could not be
21	allocated for processing, Z_STREAM_ERROR if an invalid compression
22	level is supplied, Z_VERSION_ERROR if the version of zlib.h and the
23	version of the library linked do not match, or Z_ERRNO if there is
24	an error reading or writing the files. */
25	int def(FILE source, FILE dest, int level)
26	{
27	int ret, flush;
28	unsigned have;
29	z_stream strm;
30	char in[CHUNK];
31	char out[CHUNK];
32
33	/* allocate deflate state */
34	strm.zalloc = Z_NULL;
35	strm.zfree = Z_NULL;
36	strm.opaque = Z_NULL;
37	ret = deflateInit(&strm, level);
38	if (ret != Z_OK)
39	return ret;
40
41	/* compress until end of file */
42	do {
43	strm.avail_in = fread(in, 1, CHUNK, source);
44	if (ferror(source)) {
45	(void)deflateEnd(&strm);
46	return Z_ERRNO;
47	}
48	flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
49	strm.next_in = in;
50
51	/* run deflate() on input until output buffer not full, finish
52	compression if all of source has been read in */
53	do {
54	strm.avail_out = CHUNK;
55	strm.next_out = out;
56	ret = deflate(&strm, flush); /* no bad return value */
57	assert(ret != Z_STREAM_ERROR); /* state not clobbered */
58	have = CHUNK - strm.avail_out;
59	if (fwrite(out, 1, have, dest) != have \|\| ferror(dest)) {
60	(void)deflateEnd(&strm);
61	return Z_ERRNO;
62	}
63	} while (strm.avail_out == 0);
64	assert(strm.avail_in == 0); /* all input will be used */
65
66	/* done when last data in file processed */
67	} while (flush != Z_FINISH);
68	assert(ret == Z_STREAM_END); /* stream will be complete */
69
70	/* clean up and return */
71	(void)deflateEnd(&strm);
72	return Z_OK;
73	}
74
75	/* Decompress from file source to file dest until stream ends or EOF.
76	inf() returns Z_OK on success, Z_MEM_ERROR if memory could not be
77	allocated for processing, Z_DATA_ERROR if the deflate data is
78	invalid or incomplete, Z_VERSION_ERROR if the version of zlib.h and
79	the version of the library linked do not match, or Z_ERRNO if there
80	is an error reading or writing the files. */
81	int inf(FILE source, FILE dest)
82	{
83	int ret;
84	unsigned have;
85	z_stream strm;
86	char in[CHUNK];
87	char out[CHUNK];
88
89	/* allocate inflate state */
90	strm.zalloc = Z_NULL;
91	strm.zfree = Z_NULL;
92	strm.opaque = Z_NULL;
93	strm.avail_in = 0;
94	strm.next_in = Z_NULL;
95	ret = inflateInit(&strm);
96	if (ret != Z_OK)
97	return ret;
98
99	/* decompress until deflate stream ends or end of file */
100	do {
101	strm.avail_in = fread(in, 1, CHUNK, source);
102	if (ferror(source)) {
103	(void)inflateEnd(&strm);
104	return Z_ERRNO;
105	}
106	if (strm.avail_in == 0)
107	break;
108	strm.next_in = in;
109
110	/* run inflate() on input until output buffer not full */
111	do {
112	strm.avail_out = CHUNK;
113	strm.next_out = out;
114	ret = inflate(&strm, Z_NO_FLUSH);
115	assert(ret != Z_STREAM_ERROR); /* state not clobbered */
116	switch (ret) {
117	case Z_NEED_DICT:
118	ret = Z_DATA_ERROR; /* and fall through */
119	case Z_DATA_ERROR:
120	case Z_MEM_ERROR:
121	(void)inflateEnd(&strm);
122	return ret;
123	}
124	have = CHUNK - strm.avail_out;
125	if (fwrite(out, 1, have, dest) != have \|\| ferror(dest)) {
126	(void)inflateEnd(&strm);
127	return Z_ERRNO;
128	}
129	} while (strm.avail_out == 0);
130	assert(strm.avail_in == 0); /* all input will be used */
131
132	/* done when inflate() says it's done */
133	} while (ret != Z_STREAM_END);
134
135	/* clean up and return */
136	(void)inflateEnd(&strm);
137	return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
138	}
139
140	/* report a zlib or i/o error */
141	void zerr(int ret)
142	{
143	fputs("zpipe: ", stderr);
144	switch (ret) {
145	case Z_ERRNO:
146	if (ferror(stdin))
147	fputs("error reading stdin\n", stderr);
148	if (ferror(stdout))
149	fputs("error writing stdout\n", stderr);
150	break;
151	case Z_STREAM_ERROR:
152	fputs("invalid compression level\n", stderr);
153	break;
154	case Z_DATA_ERROR:
155	fputs("invalid or incomplete deflate data\n", stderr);
156	break;
157	case Z_MEM_ERROR:
158	fputs("out of memory\n", stderr);
159	break;
160	case Z_VERSION_ERROR:
161	fputs("zlib version mismatch!\n", stderr);
162	}
163	}