minigzip.c
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1 /* minigzip.c -- simulate gzip using the zlib compression library
2  * Copyright (C) 1995-2005 Jean-loup Gailly.
3  * For conditions of distribution and use, see copyright notice in zlib.h
4  */
5 
6 /*
7  * minigzip is a minimal implementation of the gzip utility. This is
8  * only an example of using zlib and isn't meant to replace the
9  * full-featured gzip. No attempt is made to deal with file systems
10  * limiting names to 14 or 8+3 characters, etc... Error checking is
11  * very limited. So use minigzip only for testing; use gzip for the
12  * real thing. On MSDOS, use only on file names without extension
13  * or in pipe mode.
14  */
15 
16 /* @(#) $Id$ */
17 
18 #include <stdio.h>
19 #include "zlib.h"
20 
21 #ifdef STDC
22 # include <string.h>
23 # include <stdlib.h>
24 #endif
25 
26 #ifdef USE_MMAP
27 # include <sys/types.h>
28 # include <sys/mman.h>
29 # include <sys/stat.h>
30 #endif
31 
32 #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
33 # include <fcntl.h>
34 # include <io.h>
35 # define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
36 #else
37 # define SET_BINARY_MODE(file)
38 #endif
39 
40 #ifdef VMS
41 # define unlink delete
42 # define GZ_SUFFIX "-gz"
43 #endif
44 #ifdef RISCOS
45 # define unlink remove
46 # define GZ_SUFFIX "-gz"
47 # define fileno(file) file->__file
48 #endif
49 #if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
50 # include <unix.h> /* for fileno */
51 #endif
52 
53 #ifndef WIN32 /* unlink already in stdio.h for WIN32 */
54  extern int unlink OF((const char *));
55 #endif
56 
57 #ifndef GZ_SUFFIX
58 # define GZ_SUFFIX ".gz"
59 #endif
60 #define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)
61 
62 #define BUFLEN 16384
63 #define MAX_NAME_LEN 1024
64 
65 #ifdef MAXSEG_64K
66 # define local static
67  /* Needed for systems with limitation on stack size. */
68 #else
69 # define local
70 #endif
71 
72 char *prog;
73 
74 void error OF((const char *msg));
75 void gz_compress OF((FILE *in, gzFile out));
76 #ifdef USE_MMAP
77 int gz_compress_mmap OF((FILE *in, gzFile out));
78 #endif
79 void gz_uncompress OF((gzFile in, FILE *out));
80 void file_compress OF((char *file, char *mode));
81 void file_uncompress OF((char *file));
82 int main OF((int argc, char *argv[]));
83 
84 /* ===========================================================================
85  * Display error message and exit
86  */
87 void error(msg)
88  const char *msg;
89 {
90  fprintf(stderr, "%s: %s\n", prog, msg);
91  exit(1);
92 }
93 
94 /* ===========================================================================
95  * Compress input to output then close both files.
96  */
97 
98 void gz_compress(in, out)
99  FILE *in;
100  gzFile out;
101 {
102  local char buf[BUFLEN];
103  int len;
104  int err;
105 
106 #ifdef USE_MMAP
107  /* Try first compressing with mmap. If mmap fails (minigzip used in a
108  * pipe), use the normal fread loop.
109  */
110  if (gz_compress_mmap(in, out) == Z_OK) return;
111 #endif
112  for (;;) {
113  len = (int)fread(buf, 1, sizeof(buf), in);
114  if (ferror(in)) {
115  perror("fread");
116  exit(1);
117  }
118  if (len == 0) break;
119 
120  if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
121  }
122  fclose(in);
123  if (gzclose(out) != Z_OK) error("failed gzclose");
124 }
125 
126 #ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */
127 
128 /* Try compressing the input file at once using mmap. Return Z_OK if
129  * if success, Z_ERRNO otherwise.
130  */
131 int gz_compress_mmap(in, out)
132  FILE *in;
133  gzFile out;
134 {
135  int len;
136  int err;
137  int ifd = fileno(in);
138  caddr_t buf; /* mmap'ed buffer for the entire input file */
139  off_t buf_len; /* length of the input file */
140  struct stat sb;
141 
142  /* Determine the size of the file, needed for mmap: */
143  if (fstat(ifd, &sb) < 0) return Z_ERRNO;
144  buf_len = sb.st_size;
145  if (buf_len <= 0) return Z_ERRNO;
146 
147  /* Now do the actual mmap: */
148  buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
149  if (buf == (caddr_t)(-1)) return Z_ERRNO;
150 
151  /* Compress the whole file at once: */
152  len = gzwrite(out, (char *)buf, (unsigned)buf_len);
153 
154  if (len != (int)buf_len) error(gzerror(out, &err));
155 
156  munmap(buf, buf_len);
157  fclose(in);
158  if (gzclose(out) != Z_OK) error("failed gzclose");
159  return Z_OK;
160 }
161 #endif /* USE_MMAP */
162 
163 /* ===========================================================================
164  * Uncompress input to output then close both files.
165  */
166 void gz_uncompress(in, out)
167  gzFile in;
168  FILE *out;
169 {
170  local char buf[BUFLEN];
171  int len;
172  int err;
173 
174  for (;;) {
175  len = gzread(in, buf, sizeof(buf));
176  if (len < 0) error (gzerror(in, &err));
177  if (len == 0) break;
178 
179  if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
180  error("failed fwrite");
181  }
182  }
183  if (fclose(out)) error("failed fclose");
184 
185  if (gzclose(in) != Z_OK) error("failed gzclose");
186 }
187 
188 
189 /* ===========================================================================
190  * Compress the given file: create a corresponding .gz file and remove the
191  * original.
192  */
193 void file_compress(file, mode)
194  char *file;
195  char *mode;
196 {
197  local char outfile[MAX_NAME_LEN];
198  FILE *in;
199  gzFile out;
200 
201  strcpy(outfile, file);
202  strcat(outfile, GZ_SUFFIX);
203 
204  in = fopen(file, "rb");
205  if (in == NULL) {
206  perror(file);
207  exit(1);
208  }
209  out = gzopen(outfile, mode);
210  if (out == NULL) {
211  fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
212  exit(1);
213  }
214  gz_compress(in, out);
215 
216  unlink(file);
217 }
218 
219 
220 /* ===========================================================================
221  * Uncompress the given file and remove the original.
222  */
223 void file_uncompress(file)
224  char *file;
225 {
226  local char buf[MAX_NAME_LEN];
227  char *infile, *outfile;
228  FILE *out;
229  gzFile in;
230  uInt len = (uInt)strlen(file);
231 
232  strcpy(buf, file);
233 
234  if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
235  infile = file;
236  outfile = buf;
237  outfile[len-3] = '\0';
238  } else {
239  outfile = file;
240  infile = buf;
241  strcat(infile, GZ_SUFFIX);
242  }
243  in = gzopen(infile, "rb");
244  if (in == NULL) {
245  fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
246  exit(1);
247  }
248  out = fopen(outfile, "wb");
249  if (out == NULL) {
250  perror(file);
251  exit(1);
252  }
253 
254  gz_uncompress(in, out);
255 
256  unlink(infile);
257 }
258 
259 
260 /* ===========================================================================
261  * Usage: minigzip [-d] [-f] [-h] [-r] [-1 to -9] [files...]
262  * -d : decompress
263  * -f : compress with Z_FILTERED
264  * -h : compress with Z_HUFFMAN_ONLY
265  * -r : compress with Z_RLE
266  * -1 to -9 : compression level
267  */
268 
269 int main(argc, argv)
270  int argc;
271  char *argv[];
272 {
273  int uncompr = 0;
274  gzFile file;
275  char outmode[20];
276 
277  strcpy(outmode, "wb6 ");
278 
279  prog = argv[0];
280  argc--, argv++;
281 
282  while (argc > 0) {
283  if (strcmp(*argv, "-d") == 0)
284  uncompr = 1;
285  else if (strcmp(*argv, "-f") == 0)
286  outmode[3] = 'f';
287  else if (strcmp(*argv, "-h") == 0)
288  outmode[3] = 'h';
289  else if (strcmp(*argv, "-r") == 0)
290  outmode[3] = 'R';
291  else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
292  (*argv)[2] == 0)
293  outmode[2] = (*argv)[1];
294  else
295  break;
296  argc--, argv++;
297  }
298  if (outmode[3] == ' ')
299  outmode[3] = 0;
300  if (argc == 0) {
301  SET_BINARY_MODE(stdin);
302  SET_BINARY_MODE(stdout);
303  if (uncompr) {
304  file = gzdopen(fileno(stdin), "rb");
305  if (file == NULL) error("can't gzdopen stdin");
306  gz_uncompress(file, stdout);
307  } else {
308  file = gzdopen(fileno(stdout), outmode);
309  if (file == NULL) error("can't gzdopen stdout");
310  gz_compress(stdin, file);
311  }
312  } else {
313  do {
314  if (uncompr) {
315  file_uncompress(*argv);
316  } else {
317  file_compress(*argv, outmode);
318  }
319  } while (argv++, --argc);
320  }
321  return 0;
322 }
file_uncompress
void file_uncompress(char *file)
Definition: minigzip.c:223
Z_ERRNO
#define Z_ERRNO
Definition: zlib.h:173
gzopen
gzFile ZEXPORT gzopen(char *path, const char *mode) const
Definition: gzio.c:208
gzFile
voidp gzFile
Definition: zlib.h:1066
gz_compress
void gz_compress(FILE *in, gzFile out)
Definition: minigzip.c:98
gzread
int ZEXPORT gzread(gzFile file, voidp buf, unsigned len)
Definition: gzio.c:394
gzdopen
gzFile ZEXPORT gzdopen(int fd, const char *mode)
Definition: gzio.c:219
MAX_NAME_LEN
#define MAX_NAME_LEN
Definition: minigzip.c:63
GZ_SUFFIX
#define GZ_SUFFIX
Definition: minigzip.c:58
int
typedef int
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Definition: cdjpeg.h:141
prog
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Definition: minigzip.c:72
Z_OK
#define Z_OK
Definition: zlib.h:170
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Definition: gzio.c:953
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Definition: png.h:2726
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Definition: gzio.c:987
OF
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main
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Definition: minigzip.c:269
error
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Definition: minigzip.c:87
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Definition: gzio.c:559
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Definition: minigzip.c:166
BUFLEN
#define BUFLEN
Definition: minigzip.c:62
SUFFIX_LEN
#define SUFFIX_LEN
Definition: minigzip.c:60
file_compress
void file_compress(char *file, char *mode)
Definition: minigzip.c:193
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Definition: minigzip.c:37
zlib.h
local
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Definition: minigzip.c:69


openhrp3
Author(s): AIST, General Robotix Inc., Nakamura Lab of Dept. of Mechano Informatics at University of Tokyo
autogenerated on Wed Sep 7 2022 02:51:03