summaryrefslogtreecommitdiffstats
path: root/tools/zpipe.c
blob: 3806942508cac42b234d3f7e1f97eaa96632ef7a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
/* zpipe.c: example of proper use of zlib's inflate() and deflate()
   Not copyrighted -- provided to the public domain
   Version 1.5  11 December 2005  Mark Adler 
   Version 2.0  03 June     2009  Rainer Gerhards */

/* RSYSLOG NOTE:
 * This file is primarily been used as a testing aid for rsyslog. We do NOT
 * properly maintain it and it has been brought to our attention that it may
 * have some security issues. However, we prefer not to remove the file as it
 * may turn out to be useful for further testing. All users are advised NOT
 * to base any development on this version here, but rather look for the
 * original zpipe.c by the authors mentioned above.
 *
 * This file is beeing distributed as part of rsyslog, but is just an
 * add-on. Most importantly, rsyslog's copyright does not apply but
 * rather the (non-) copyright stated above.
 */

/* 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()
   1.4  11 Dec 2005  Add hack to avoid MSDOS end-of-line conversions
                     Avoid some compiler warnings for input and output buffers
   2.0  03 Jun 2009  Add hack to support multiple deflate records inside a single
   		     file on inflate. This is needed in order to support reading
		     files created by rsyslog's zip output writer.
 */

#include "config.h"
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "zlib.h"

#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
#  include <fcntl.h>
#  include <io.h>
#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
#else
#  define SET_BINARY_MODE(file)
#endif

#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;
    unsigned char in[CHUNK];
    unsigned 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;
}


/* initialize stream for deflating (we need this in case of 
 * multiple records.
 * rgerhards, 2009-06-03
 */
int doInflateInit(z_stream *strm)
{
    int ret;

    /* 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);
    return ret;
}


/* 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;
    unsigned char in[CHUNK];
    int len;
    unsigned char *next_in_save;
    unsigned char out[CHUNK];

    ret = doInflateInit(&strm);
    if (ret != Z_OK)
        return ret;

    /* decompress until deflate stream ends or end of file */
    do {
        len = fread(in, 1, CHUNK, source);
        if (ferror(source)) {
            (void)inflateEnd(&strm);
            return Z_ERRNO;
        }
        if (len == 0) {
            break;
	}
        strm.avail_in = len;
        strm.next_in = in;

        /* run inflate() on input until output buffer not full */
        strm.avail_out = CHUNK;
        strm.next_out = out;
        do {
	/*	fprintf(stderr, "---inner LOOP---, avail_in %d, avail_out %d Byte 0: %x, 1: %x\n", strm.avail_in, strm.avail_out, *strm.next_in, *(strm.next_in+1));*/
		do {
		    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);
		/* handle the case that more than one deflate record is contained
		 * in a single file. -- rgerhards, 2009-06-03
		 */
		if(ret == Z_STREAM_END) {
			len -= strm.total_in;
			if(len > 0) {
				next_in_save = strm.next_in;
				(void)inflateEnd(&strm);
				ret = doInflateInit(&strm);
				if (ret != Z_OK)
				    return ret;
				strm.avail_in = len;
				strm.next_in = next_in_save;
				strm.avail_out = CHUNK;
				strm.next_out = out;
				ret = Z_OK; /* continue outer loop */
			}
		}
	} while (strm.avail_in > 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: ", stdout);
    switch (ret) {
    case Z_ERRNO:
        if (ferror(stdin))
            fputs("error reading stdin\n", stdout);
        if (ferror(stdout))
            fputs("error writing stdout\n", stdout);
        break;
    case Z_STREAM_ERROR:
        fputs("invalid compression level\n", stdout);
        break;
    case Z_DATA_ERROR:
        fputs("invalid or incomplete deflate data\n", stdout);
        break;
    case Z_MEM_ERROR:
        fputs("out of memory\n", stdout);
        break;
    case Z_VERSION_ERROR:
        fputs("zlib version mismatch!\n", stdout);
    }
}

/* compress or decompress from stdin to stdout */
int main(int argc, char **argv)
{
    int ret;

    /* avoid end-of-line conversions */
    SET_BINARY_MODE(stdin);
    SET_BINARY_MODE(stdout);

    /* do compression if no arguments */
    if (argc == 1) {
        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("zpipe usage: zpipe [-d] < source > dest\n", stdout);
        return 1;
    }
}