ext/fileinfo/libmagic/magic.c

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This source file includes following definitions.
get_default_magic
magic_getpath
magic_open
unreadable_info
magic_close
magic_load
magic_compile
magic_list
close_and_restore
magic_descriptor
magic_file
magic_stream
file_or_stream
magic_buffer
magic_error
magic_errno
magic_setflags
magic_version
   1 /*
   2  * Copyright (c) Christos Zoulas 2003.
   3  * All Rights Reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice immediately at the beginning of the file, without modification,
  10  *    this list of conditions, and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  19  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27 
  28 #include "file.h"
  29 
  30 #ifndef lint
  31 FILE_RCSID("@(#)$File: magic.c,v 1.81 2013/11/29 15:42:51 christos Exp $")
  32 #endif  /* lint */
  33 
  34 #include "magic.h"
  35 
  36 #include <stdlib.h>
  37 #ifdef PHP_WIN32
  38 #include "win32/unistd.h"
  39 #else
  40 #include <unistd.h>
  41 #endif
  42 #include <string.h>
  43 #ifdef PHP_WIN32
  44 # include "config.w32.h"
  45 #else
  46 # include "php_config.h"
  47 #endif
  48 
  49 #ifdef PHP_WIN32
  50 #include <shlwapi.h>
  51 #endif
  52 
  53 #include <limits.h>     /* for PIPE_BUF */
  54 
  55 #if defined(HAVE_UTIMES)
  56 # include <sys/time.h>
  57 #elif defined(HAVE_UTIME)
  58 # if defined(HAVE_SYS_UTIME_H)
  59 #  include <sys/utime.h>
  60 # elif defined(HAVE_UTIME_H)
  61 #  include <utime.h>
  62 # endif
  63 #endif
  64 
  65 #ifdef HAVE_UNISTD_H
  66 #include <unistd.h>     /* for read() */
  67 #endif
  68 
  69 #ifndef PIPE_BUF
  70 /* Get the PIPE_BUF from pathconf */
  71 #ifdef _PC_PIPE_BUF
  72 #define PIPE_BUF pathconf(".", _PC_PIPE_BUF)
  73 #else
  74 #define PIPE_BUF 512
  75 #endif
  76 #endif
  77 
  78 #ifdef PHP_WIN32
  79 # undef S_IFLNK
  80 # undef S_IFIFO
  81 #endif
  82 
  83 private void close_and_restore(const struct magic_set *, const char *, int,
  84     const struct stat *);
  85 private int unreadable_info(struct magic_set *, mode_t, const char *);
  86 #if 0
  87 private const char* get_default_magic(void);
  88 #endif
  89 private const char *file_or_stream(struct magic_set *, const char *, php_stream *);
  90 
  91 #ifndef STDIN_FILENO
  92 #define STDIN_FILENO    0
  93 #endif
  94 
  95 /* XXX this functionality is excluded in php, enable it in apprentice.c:340 */
  96 #if 0
  97 private const char *
  98 get_default_magic(void)
  99 {
 100         static const char hmagic[] = "/.magic/magic.mgc";
 101         static char *default_magic;
 102         char *home, *hmagicpath;
 103 
 104 #ifndef PHP_WIN32
 105         struct stat st;
 106 
 107         if (default_magic) {
 108                 free(default_magic);
 109                 default_magic = NULL;
 110         }
 111         if ((home = getenv("HOME")) == NULL)
 112                 return MAGIC;
 113 
 114         if (asprintf(&hmagicpath, "%s/.magic.mgc", home) < 0)
 115                 return MAGIC;
 116         if (stat(hmagicpath, &st) == -1) {
 117                 free(hmagicpath);
 118         if (asprintf(&hmagicpath, "%s/.magic", home) < 0)
 119                 return MAGIC;
 120         if (stat(hmagicpath, &st) == -1)
 121                 goto out;
 122         if (S_ISDIR(st.st_mode)) {
 123                 free(hmagicpath);
 124                 if (asprintf(&hmagicpath, "%s/%s", home, hmagic) < 0)
 125                         return MAGIC;
 126                 if (access(hmagicpath, R_OK) == -1)
 127                         goto out;
 128         }
 129         }
 130 
 131         if (asprintf(&default_magic, "%s:%s", hmagicpath, MAGIC) < 0)
 132                 goto out;
 133         free(hmagicpath);
 134         return default_magic;
 135 out:
 136         default_magic = NULL;
 137         free(hmagicpath);
 138         return MAGIC;
 139 #else
 140         char *hmagicp = hmagicpath;
 141         char *tmppath = NULL;
 142         LPTSTR dllpath;
 143 
 144 #define APPENDPATH() \
 145         do { \
 146                 if (tmppath && access(tmppath, R_OK) != -1) { \
 147                         if (hmagicpath == NULL) \
 148                                 hmagicpath = tmppath; \
 149                         else { \
 150                                 if (asprintf(&hmagicp, "%s%c%s", hmagicpath, \
 151                                     PATHSEP, tmppath) >= 0) { \
 152                                         free(hmagicpath); \
 153                                         hmagicpath = hmagicp; \
 154                                 } \
 155                                 free(tmppath); \
 156                         } \
 157                         tmppath = NULL; \
 158                 } \
 159         } while (/*CONSTCOND*/0)
 160                                 
 161         if (default_magic) {
 162                 free(default_magic);
 163                 default_magic = NULL;
 164         }
 165 
 166         /* First, try to get user-specific magic file */
 167         if ((home = getenv("LOCALAPPDATA")) == NULL) {
 168                 if ((home = getenv("USERPROFILE")) != NULL)
 169                         if (asprintf(&tmppath,
 170                             "%s/Local Settings/Application Data%s", home,
 171                             hmagic) < 0)
 172                                 tmppath = NULL;
 173         } else {
 174                 if (asprintf(&tmppath, "%s%s", home, hmagic) < 0)
 175                         tmppath = NULL;
 176         }
 177 
 178         APPENDPATH();
 179 
 180         /* Second, try to get a magic file from Common Files */
 181         if ((home = getenv("COMMONPROGRAMFILES")) != NULL) {
 182                 if (asprintf(&tmppath, "%s%s", home, hmagic) >= 0)
 183                         APPENDPATH();
 184         }
 185 
 186         /* Third, try to get magic file relative to dll location */
 187         dllpath = malloc(sizeof(*dllpath) * (MAX_PATH + 1));
 188         dllpath[MAX_PATH] = 0;  /* just in case long path gets truncated and not null terminated */
 189         if (GetModuleFileNameA(NULL, dllpath, MAX_PATH)){
 190                 PathRemoveFileSpecA(dllpath);
 191                 if (strlen(dllpath) > 3 &&
 192                     stricmp(&dllpath[strlen(dllpath) - 3], "bin") == 0) {
 193                         if (asprintf(&tmppath,
 194                             "%s/../share/misc/magic.mgc", dllpath) >= 0)
 195                                 APPENDPATH();
 196                 } else {
 197                         if (asprintf(&tmppath,
 198                             "%s/share/misc/magic.mgc", dllpath) >= 0)
 199                                 APPENDPATH();
 200                         else if (asprintf(&tmppath,
 201                             "%s/magic.mgc", dllpath) >= 0)
 202                                 APPENDPATH();
 203                 }
 204         }
 205 
 206         /* Don't put MAGIC constant - it likely points to a file within MSys
 207         tree */
 208         default_magic = hmagicpath;
 209         return default_magic;
 210 #endif
 211 }
 212 
 213 public const char *
 214 magic_getpath(const char *magicfile, int action)
 215 {
 216         if (magicfile != NULL)
 217                 return magicfile;
 218 
 219         magicfile = getenv("MAGIC");
 220         if (magicfile != NULL)
 221                 return magicfile;
 222 
 223         return action == FILE_LOAD ? get_default_magic() : MAGIC;
 224 }
 225 #endif
 226 
 227 public struct magic_set *
 228 magic_open(int flags)
 229 {
 230         return file_ms_alloc(flags);
 231 }
 232 
 233 private int
 234 unreadable_info(struct magic_set *ms, mode_t md, const char *file)
 235 {
 236         /* We cannot open it, but we were able to stat it. */
 237         if (access(file, W_OK) == 0)
 238                 if (file_printf(ms, "writable, ") == -1)
 239                         return -1;
 240         if (access(file, X_OK) == 0)
 241                 if (file_printf(ms, "executable, ") == -1)
 242                         return -1;
 243         if (S_ISREG(md))
 244                 if (file_printf(ms, "regular file, ") == -1)
 245                         return -1;
 246         if (file_printf(ms, "no read permission") == -1)
 247                 return -1;
 248         return 0;
 249 }
 250 
 251 public void
 252 magic_close(struct magic_set *ms)
 253 {
 254         if (ms == NULL)
 255                 return;
 256         file_ms_free(ms);
 257 }
 258 
 259 /*
 260  * load a magic file
 261  */
 262 public int
 263 magic_load(struct magic_set *ms, const char *magicfile)
 264 {
 265         if (ms == NULL)
 266                 return -1;
 267         return file_apprentice(ms, magicfile, FILE_LOAD);
 268 }
 269 
 270 public int
 271 magic_compile(struct magic_set *ms, const char *magicfile)
 272 {
 273         if (ms == NULL)
 274                 return -1;
 275         return file_apprentice(ms, magicfile, FILE_COMPILE);
 276 }
 277 
 278 
 279 public int
 280 magic_list(struct magic_set *ms, const char *magicfile)
 281 {
 282         if (ms == NULL)
 283                 return -1;
 284         return file_apprentice(ms, magicfile, FILE_LIST);
 285 }
 286 
 287 private void
 288 close_and_restore(const struct magic_set *ms, const char *name, int fd,
 289     const struct stat *sb)
 290 {
 291 
 292         if ((ms->flags & MAGIC_PRESERVE_ATIME) != 0) {
 293                 /*
 294                  * Try to restore access, modification times if read it.
 295                  * This is really *bad* because it will modify the status
 296                  * time of the file... And of course this will affect
 297                  * backup programs
 298                  */
 299 #ifdef HAVE_UTIMES
 300                 struct timeval  utsbuf[2];
 301                 (void)memset(utsbuf, 0, sizeof(utsbuf));
 302                 utsbuf[0].tv_sec = sb->st_atime;
 303                 utsbuf[1].tv_sec = sb->st_mtime;
 304 
 305                 (void) utimes(name, utsbuf); /* don't care if loses */
 306 #elif defined(HAVE_UTIME_H) || defined(HAVE_SYS_UTIME_H)
 307                 struct utimbuf  utbuf;
 308 
 309                 (void)memset(&utbuf, 0, sizeof(utbuf));
 310                 utbuf.actime = sb->st_atime;
 311                 utbuf.modtime = sb->st_mtime;
 312                 (void) utime(name, &utbuf); /* don't care if loses */
 313 #endif
 314         }
 315 }
 316 
 317 
 318 /*
 319  * find type of descriptor
 320  */
 321 public const char *
 322 magic_descriptor(struct magic_set *ms, int fd)
 323 {
 324         if (ms == NULL)
 325                 return NULL;
 326         return file_or_stream(ms, NULL, NULL);
 327 }
 328 
 329 /*
 330  * find type of named file
 331  */
 332 public const char *
 333 magic_file(struct magic_set *ms, const char *inname)
 334 {
 335         if (ms == NULL)
 336                 return NULL;
 337         return file_or_stream(ms, inname, NULL);
 338 }
 339 
 340 public const char *
 341 magic_stream(struct magic_set *ms, php_stream *stream)
 342 {
 343         if (ms == NULL)
 344                 return NULL;
 345         return file_or_stream(ms, NULL, stream);
 346 }
 347 
 348 private const char *
 349 file_or_stream(struct magic_set *ms, const char *inname, php_stream *stream)
 350 {
 351         int     rv = -1;
 352         unsigned char *buf;
 353         struct stat     sb;
 354         ssize_t nbytes = 0;     /* number of bytes read from a datafile */
 355         int no_in_stream = 0;
 356         TSRMLS_FETCH();
 357 
 358         if (!inname && !stream) {
 359                 return NULL;
 360         }
 361 
 362         /*
 363          * one extra for terminating '\0', and
 364          * some overlapping space for matches near EOF
 365          */
 366 #define SLOP (1 + sizeof(union VALUETYPE))
 367         buf = emalloc(HOWMANY + SLOP);
 368 
 369         if (file_reset(ms) == -1)
 370                 goto done;
 371 
 372         switch (file_fsmagic(ms, inname, &sb, stream)) {
 373         case -1:                /* error */
 374                 goto done;
 375         case 0:                 /* nothing found */
 376                 break;
 377         default:                /* matched it and printed type */
 378                 rv = 0;
 379                 goto done;
 380         }
 381 
 382         errno = 0;
 383 
 384         if (!stream && inname) {
 385                 no_in_stream = 1;
 386                 stream = php_stream_open_wrapper((char *)inname, "rb", REPORT_ERRORS, NULL);
 387         }
 388 
 389         if (!stream) {
 390                 if (unreadable_info(ms, sb.st_mode, inname) == -1)
 391                         goto done;
 392                 rv = 0;
 393                 goto done;
 394         }
 395 
 396 #ifdef O_NONBLOCK
 397 /* we should be already be in non blocking mode for network socket */
 398 #endif
 399 
 400         /*
 401          * try looking at the first HOWMANY bytes
 402          */
 403         if ((nbytes = php_stream_read(stream, (char *)buf, HOWMANY)) < 0) {
 404                 file_error(ms, errno, "cannot read `%s'", inname);
 405                 goto done;
 406         }
 407 
 408         (void)memset(buf + nbytes, 0, SLOP); /* NUL terminate */
 409         if (file_buffer(ms, stream, inname, buf, (size_t)nbytes) == -1)
 410                 goto done;
 411         rv = 0;
 412 done:
 413         efree(buf);
 414 
 415         if (no_in_stream && stream) {
 416                 php_stream_close(stream);
 417         }
 418 
 419         close_and_restore(ms, inname, 0, &sb);
 420         return rv == 0 ? file_getbuffer(ms) : NULL;
 421 }
 422 
 423 
 424 public const char *
 425 magic_buffer(struct magic_set *ms, const void *buf, size_t nb)
 426 {
 427         if (ms == NULL)
 428                 return NULL;
 429         if (file_reset(ms) == -1)
 430                 return NULL;
 431         /*
 432          * The main work is done here!
 433          * We have the file name and/or the data buffer to be identified. 
 434          */
 435         if (file_buffer(ms, NULL, NULL, buf, nb) == -1) {
 436                 return NULL;
 437         }
 438         return file_getbuffer(ms);
 439 }
 440 
 441 public const char *
 442 magic_error(struct magic_set *ms)
 443 {
 444         if (ms == NULL)
 445                 return "Magic database is not open";
 446         return (ms->event_flags & EVENT_HAD_ERR) ? ms->o.buf : NULL;
 447 }
 448 
 449 public int
 450 magic_errno(struct magic_set *ms)
 451 {
 452         if (ms == NULL)
 453                 return EINVAL;
 454         return (ms->event_flags & EVENT_HAD_ERR) ? ms->error : 0;
 455 }
 456 
 457 public int
 458 magic_setflags(struct magic_set *ms, int flags)
 459 {
 460         if (ms == NULL)
 461                 return -1;
 462 #if !defined(HAVE_UTIME) && !defined(HAVE_UTIMES)
 463         if (flags & MAGIC_PRESERVE_ATIME)
 464                 return -1;
 465 #endif
 466         ms->flags = flags;
 467         return 0;
 468 }
 469 
 470 public int
 471 magic_version(void)
 472 {
 473         return MAGIC_VERSION;
 474 }
/* [<][>][^][v][top][bottom][index][help] */
root/ext/fileinfo/libmagic/magic.c

DEFINITIONS
