summaryrefslogblamecommitdiffstats
path: root/zlib-1.2.5/minigzip.c
blob: 9825ccc3a712e19fe8bccb52214f9da823a6757f (plain) (tree)
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
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440























































































































































































































































































































































































































































                                                                               
/* minigzip.c -- simulate gzip using the zlib compression library
 * Copyright (C) 1995-2006, 2010 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

/*
 * minigzip is a minimal implementation of the gzip utility. This is
 * only an example of using zlib and isn't meant to replace the
 * full-featured gzip. No attempt is made to deal with file systems
 * limiting names to 14 or 8+3 characters, etc... Error checking is
 * very limited. So use minigzip only for testing; use gzip for the
 * real thing. On MSDOS, use only on file names without extension
 * or in pipe mode.
 */

/* @(#) $Id$ */

#include "zlib.h"
#include <stdio.h>

#ifdef STDC
#  include <string.h>
#  include <stdlib.h>
#endif

#ifdef USE_MMAP
#  include <sys/types.h>
#  include <sys/mman.h>
#  include <sys/stat.h>
#endif

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

#ifdef VMS
#  define unlink delete
#  define GZ_SUFFIX "-gz"
#endif
#ifdef RISCOS
#  define unlink remove
#  define GZ_SUFFIX "-gz"
#  define fileno(file) file->__file
#endif
#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
#  include <unix.h> /* for fileno */
#endif

#if !defined(Z_HAVE_UNISTD_H) && !defined(_LARGEFILE64_SOURCE)
#ifndef WIN32 /* unlink already in stdio.h for WIN32 */
  extern int unlink OF((const char *));
#endif
#endif

#if defined(UNDER_CE)
#  include <windows.h>
#  define perror(s) pwinerror(s)

/* Map the Windows error number in ERROR to a locale-dependent error
   message string and return a pointer to it.  Typically, the values
   for ERROR come from GetLastError.

   The string pointed to shall not be modified by the application,
   but may be overwritten by a subsequent call to strwinerror

   The strwinerror function does not change the current setting
   of GetLastError.  */

static char *strwinerror (error)
     DWORD error;
{
    static char buf[1024];

    wchar_t *msgbuf;
    DWORD lasterr = GetLastError();
    DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
        | FORMAT_MESSAGE_ALLOCATE_BUFFER,
        NULL,
        error,
        0, /* Default language */
        (LPVOID)&msgbuf,
        0,
        NULL);
    if (chars != 0) {
        /* If there is an \r\n appended, zap it.  */
        if (chars >= 2
            && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
            chars -= 2;
            msgbuf[chars] = 0;
        }

        if (chars > sizeof (buf) - 1) {
            chars = sizeof (buf) - 1;
            msgbuf[chars] = 0;
        }

        wcstombs(buf, msgbuf, chars + 1);
        LocalFree(msgbuf);
    }
    else {
        sprintf(buf, "unknown win32 error (%ld)", error);
    }

    SetLastError(lasterr);
    return buf;
}

static void pwinerror (s)
    const char *s;
{
    if (s && *s)
        fprintf(stderr, "%s: %s\n", s, strwinerror(GetLastError ()));
    else
        fprintf(stderr, "%s\n", strwinerror(GetLastError ()));
}

#endif /* UNDER_CE */

#ifndef GZ_SUFFIX
#  define GZ_SUFFIX ".gz"
#endif
#define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)

#define BUFLEN      16384
#define MAX_NAME_LEN 1024

#ifdef MAXSEG_64K
#  define local static
   /* Needed for systems with limitation on stack size. */
#else
#  define local
#endif

char *prog;

void error            OF((const char *msg));
void gz_compress      OF((FILE   *in, gzFile out));
#ifdef USE_MMAP
int  gz_compress_mmap OF((FILE   *in, gzFile out));
#endif
void gz_uncompress    OF((gzFile in, FILE   *out));
void file_compress    OF((char  *file, char *mode));
void file_uncompress  OF((char  *file));
int  main             OF((int argc, char *argv[]));

/* ===========================================================================
 * Display error message and exit
 */
void error(msg)
    const char *msg;
{
    fprintf(stderr, "%s: %s\n", prog, msg);
    exit(1);
}

/* ===========================================================================
 * Compress input to output then close both files.
 */

void gz_compress(in, out)
    FILE   *in;
    gzFile out;
{
    local char buf[BUFLEN];
    int len;
    int err;

#ifdef USE_MMAP
    /* Try first compressing with mmap. If mmap fails (minigzip used in a
     * pipe), use the normal fread loop.
     */
    if (gz_compress_mmap(in, out) == Z_OK) return;
#endif
    for (;;) {
        len = (int)fread(buf, 1, sizeof(buf), in);
        if (ferror(in)) {
            perror("fread");
            exit(1);
        }
        if (len == 0) break;

        if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
    }
    fclose(in);
    if (gzclose(out) != Z_OK) error("failed gzclose");
}

#ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */

/* Try compressing the input file at once using mmap. Return Z_OK if
 * if success, Z_ERRNO otherwise.
 */
int gz_compress_mmap(in, out)
    FILE   *in;
    gzFile out;
{
    int len;
    int err;
    int ifd = fileno(in);
    caddr_t buf;    /* mmap'ed buffer for the entire input file */
    off_t buf_len;  /* length of the input file */
    struct stat sb;

    /* Determine the size of the file, needed for mmap: */
    if (fstat(ifd, &sb) < 0) return Z_ERRNO;
    buf_len = sb.st_size;
    if (buf_len <= 0) return Z_ERRNO;

    /* Now do the actual mmap: */
    buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
    if (buf == (caddr_t)(-1)) return Z_ERRNO;

    /* Compress the whole file at once: */
    len = gzwrite(out, (char *)buf, (unsigned)buf_len);

    if (len != (int)buf_len) error(gzerror(out, &err));

    munmap(buf, buf_len);
    fclose(in);
    if (gzclose(out) != Z_OK) error("failed gzclose");
    return Z_OK;
}
#endif /* USE_MMAP */

/* ===========================================================================
 * Uncompress input to output then close both files.
 */
void gz_uncompress(in, out)
    gzFile in;
    FILE   *out;
{
    local char buf[BUFLEN];
    int len;
    int err;

    for (;;) {
        len = gzread(in, buf, sizeof(buf));
        if (len < 0) error (gzerror(in, &err));
        if (len == 0) break;

        if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
            error("failed fwrite");
        }
    }
    if (fclose(out)) error("failed fclose");

    if (gzclose(in) != Z_OK) error("failed gzclose");
}


/* ===========================================================================
 * Compress the given file: create a corresponding .gz file and remove the
 * original.
 */
void file_compress(file, mode)
    char  *file;
    char  *mode;
{
    local char outfile[MAX_NAME_LEN];
    FILE  *in;
    gzFile out;

    if (strlen(file) + strlen(GZ_SUFFIX) >= sizeof(outfile)) {
        fprintf(stderr, "%s: filename too long\n", prog);
        exit(1);
    }

    strcpy(outfile, file);
    strcat(outfile, GZ_SUFFIX);

    in = fopen(file, "rb");
    if (in == NULL) {
        perror(file);
        exit(1);
    }
    out = gzopen(outfile, mode);
    if (out == NULL) {
        fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
        exit(1);
    }
    gz_compress(in, out);

    unlink(file);
}


/* ===========================================================================
 * Uncompress the given file and remove the original.
 */
void file_uncompress(file)
    char  *file;
{
    local char buf[MAX_NAME_LEN];
    char *infile, *outfile;
    FILE  *out;
    gzFile in;
    size_t len = strlen(file);

    if (len + strlen(GZ_SUFFIX) >= sizeof(buf)) {
        fprintf(stderr, "%s: filename too long\n", prog);
        exit(1);
    }

    strcpy(buf, file);

    if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
        infile = file;
        outfile = buf;
        outfile[len-3] = '\0';
    } else {
        outfile = file;
        infile = buf;
        strcat(infile, GZ_SUFFIX);
    }
    in = gzopen(infile, "rb");
    if (in == NULL) {
        fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
        exit(1);
    }
    out = fopen(outfile, "wb");
    if (out == NULL) {
        perror(file);
        exit(1);
    }

    gz_uncompress(in, out);

    unlink(infile);
}


/* ===========================================================================
 * Usage:  minigzip [-c] [-d] [-f] [-h] [-r] [-1 to -9] [files...]
 *   -c : write to standard output
 *   -d : decompress
 *   -f : compress with Z_FILTERED
 *   -h : compress with Z_HUFFMAN_ONLY
 *   -r : compress with Z_RLE
 *   -1 to -9 : compression level
 */

int main(argc, argv)
    int argc;
    char *argv[];
{
    int copyout = 0;
    int uncompr = 0;
    gzFile file;
    char *bname, outmode[20];

    strcpy(outmode, "wb6 ");

    prog = argv[0];
    bname = strrchr(argv[0], '/');
    if (bname)
      bname++;
    else
      bname = argv[0];
    argc--, argv++;

    if (!strcmp(bname, "gunzip"))
      uncompr = 1;
    else if (!strcmp(bname, "zcat"))
      copyout = uncompr = 1;

    while (argc > 0) {
      if (strcmp(*argv, "-c") == 0)
        copyout = 1;
      else if (strcmp(*argv, "-d") == 0)
        uncompr = 1;
      else if (strcmp(*argv, "-f") == 0)
        outmode[3] = 'f';
      else if (strcmp(*argv, "-h") == 0)
        outmode[3] = 'h';
      else if (strcmp(*argv, "-r") == 0)
        outmode[3] = 'R';
      else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
               (*argv)[2] == 0)
        outmode[2] = (*argv)[1];
      else
        break;
      argc--, argv++;
    }
    if (outmode[3] == ' ')
        outmode[3] = 0;
    if (argc == 0) {
        SET_BINARY_MODE(stdin);
        SET_BINARY_MODE(stdout);
        if (uncompr) {
            file = gzdopen(fileno(stdin), "rb");
            if (file == NULL) error("can't gzdopen stdin");
            gz_uncompress(file, stdout);
        } else {
            file = gzdopen(fileno(stdout), outmode);
            if (file == NULL) error("can't gzdopen stdout");
            gz_compress(stdin, file);
        }
    } else {
        if (copyout) {
            SET_BINARY_MODE(stdout);
        }
        do {
            if (uncompr) {
                if (copyout) {
                    file = gzopen(*argv, "rb");
                    if (file == NULL)
                        fprintf(stderr, "%s: can't gzopen %s\n", prog, *argv);
                    else
                        gz_uncompress(file, stdout);
                } else {
                    file_uncompress(*argv);
                }
            } else {
                if (copyout) {
                    FILE * in = fopen(*argv, "rb");

                    if (in == NULL) {
                        perror(*argv);
                    } else {
                        file = gzdopen(fileno(stdout), outmode);
                        if (file == NULL) error("can't gzdopen stdout");

                        gz_compress(in, file);
                    }

                } else {
                    file_compress(*argv, outmode);
                }
            }
        } while (argv++, --argc);
    }
    return 0;
}