WINGs/findfile.c

   1 /*
   2  *  Window Maker miscelaneous function library
   3  *
   4  *  Copyright (c) 1997-2003 Alfredo K. Kojima
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  19  *  MA 02110-1301, USA.
  20  */
  21
  22 #include "wconfig.h"
  23
  24 #include "WUtil.h"
  25
  26 #include <sys/types.h>
  27 #include <sys/stat.h>
  28 #include <fcntl.h>
  29 #include <errno.h>
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <unistd.h>
  33 #include <string.h>
  34 #include <pwd.h>
  35 #include <limits.h>
  36
  37 #ifndef PATH_MAX
  38 #define PATH_MAX  1024
  39 #endif
  40
  41
  42 char *wgethomedir()
  43 {
  44         static char *home = NULL;
  45         char *tmp;
  46         struct passwd *user;
  47
  48         if (home)
  49                 return home;
  50
  51 #ifdef HAVE_SECURE_GETENV
  52         tmp = secure_getenv("HOME");
  53 #else
  54         tmp = getenv("HOME");
  55 #endif
  56         if (tmp) {
  57                 home = wstrdup(tmp);
  58                 return home;
  59         }
  60
  61         user = getpwuid(getuid());
  62         if (!user) {
  63                 werror(_("could not get password entry for UID %i"), getuid());
  64                 home = "/";
  65                 return home;
  66         }
  67
  68         if (!user->pw_dir)
  69                 home = "/";
  70         else
  71                 home = wstrdup(user->pw_dir);
  72
  73         return home;
  74 }
  75
  76 /*
  77  * Return the home directory for the specified used
  78  *
  79  * If user not found, returns NULL, otherwise always returns a path that is
  80  * statically stored.
  81  *
  82  * Please note you must use the path before any other call to 'getpw*' or it
  83  * may be erased. This is a design choice to avoid duplication considering
  84  * the use case for this function.
  85  */
  86 static const char *getuserhomedir(const char *username)
  87 {
  88         static const char default_home[] = "/";
  89         struct passwd *user;
  90
  91         user = getpwnam(username);
  92         if (!user) {
  93                 werror(_("could not get password entry for user %s"), username);
  94                 return NULL;
  95         }
  96         if (!user->pw_dir)
  97                 return default_home;
  98         else
  99                 return user->pw_dir;
 100
 101 }
 102
 103 char *wexpandpath(const char *path)
 104 {
 105         const char *origpath = path;
 106         char buffer2[PATH_MAX + 2];
 107         char buffer[PATH_MAX + 2];
 108         int i;
 109
 110         memset(buffer, 0, PATH_MAX + 2);
 111
 112         if (*path == '~') {
 113                 const char *home;
 114
 115                 path++;
 116                 if (*path == '/' || *path == 0) {
 117                         home = wgethomedir();
 118                         if (strlen(home) > PATH_MAX ||
 119                             wstrlcpy(buffer, home, sizeof(buffer)) >= sizeof(buffer))
 120                                 goto error;
 121                 } else {
 122                         int j;
 123                         j = 0;
 124                         while (*path != 0 && *path != '/') {
 125                                 if (j > PATH_MAX)
 126                                         goto error;
 127                                 buffer2[j++] = *path;
 128                                 buffer2[j] = 0;
 129                                 path++;
 130                         }
 131                         home = getuserhomedir(buffer2);
 132                         if (!home || wstrlcat(buffer, home, sizeof(buffer)) >= sizeof(buffer))
 133                                 goto error;
 134                 }
 135         }
 136
 137         i = strlen(buffer);
 138
 139         while (*path != 0 && i <= PATH_MAX) {
 140                 char *tmp;
 141
 142                 if (*path == '$') {
 143                         int j;
 144
 145                         path++;
 146                         /* expand $(HOME) or $HOME style environment variables */
 147                         if (*path == '(') {
 148                                 path++;
 149                                 j = 0;
 150                                 while (*path != 0 && *path != ')') {
 151                                         if (j > PATH_MAX)
 152                                                 goto error;
 153                                         buffer2[j++] = *(path++);
 154                                 }
 155                                 buffer2[j] = 0;
 156                                 if (*path == ')') {
 157                                         path++;
 158                                         tmp = getenv(buffer2);
 159                                 } else {
 160                                         tmp = NULL;
 161                                 }
 162                                 if (!tmp) {
 163                                         if ((i += strlen(buffer2) + 2) > PATH_MAX)
 164                                                 goto error;
 165                                         buffer[i] = 0;
 166                                         if (wstrlcat(buffer, "$(", sizeof(buffer)) >= sizeof(buffer) ||
 167                                             wstrlcat(buffer, buffer2, sizeof(buffer)) >= sizeof(buffer))
 168                                                 goto error;
 169                                         if (*(path-1)==')') {
 170                                                 if (++i > PATH_MAX ||
 171                                                     wstrlcat(buffer, ")", sizeof(buffer)) >= sizeof(buffer))
 172                                                         goto error;
 173                                         }
 174                                 } else {
 175                                         if ((i += strlen(tmp)) > PATH_MAX ||
 176                                             wstrlcat(buffer, tmp, sizeof(buffer)) >= sizeof(buffer))
 177                                                 goto error;
 178                                 }
 179                         } else {
 180                                 j = 0;
 181                                 while (*path != 0 && *path != '/') {
 182                                         if (j > PATH_MAX)
 183                                                 goto error;
 184                                         buffer2[j++] = *(path++);
 185                                 }
 186                                 buffer2[j] = 0;
 187                                 tmp = getenv(buffer2);
 188                                 if (!tmp) {
 189                                         if ((i += strlen(buffer2) + 1) > PATH_MAX ||
 190                                             wstrlcat(buffer, "$", sizeof(buffer)) >= sizeof(buffer) ||
 191                                             wstrlcat(buffer, buffer2, sizeof(buffer)) >= sizeof(buffer))
 192                                                 goto error;
 193                                 } else {
 194                                         if ((i += strlen(tmp)) > PATH_MAX ||
 195                                             wstrlcat(buffer, tmp, sizeof(buffer)) >= sizeof(buffer))
 196                                                 goto error;
 197                                 }
 198                         }
 199                 } else {
 200                         buffer[i++] = *path;
 201                         path++;
 202                 }
 203         }
 204
 205         if (*path!=0)
 206                 goto error;
 207
 208         return wstrdup(buffer);
 209
 210 error:
 211         errno = ENAMETOOLONG;
 212         werror(_("could not expand %s"), origpath);
 213
 214         return NULL;
 215 }
 216
 217 /* return address of next char != tok or end of string whichever comes first */
 218 static const char *skipchar(const char *string, char tok)
 219 {
 220         while (*string != 0 && *string == tok)
 221                 string++;
 222
 223         return string;
 224 }
 225
 226 /* return address of next char == tok or end of string whichever comes first */
 227 static const char *nextchar(const char *string, char tok)
 228 {
 229         while (*string != 0 && *string != tok)
 230                 string++;
 231
 232         return string;
 233 }
 234
 235 /*
 236  *----------------------------------------------------------------------
 237  * findfile--
 238  *      Finds a file in a : separated list of paths. ~ expansion is also
 239  * done.
 240  *
 241  * Returns:
 242  *      The complete path for the file (in a newly allocated string) or
 243  * NULL if the file was not found.
 244  *
 245  * Side effects:
 246  *      A new string is allocated. It must be freed later.
 247  *
 248  *----------------------------------------------------------------------
 249  */
 250 char *wfindfile(const char *paths, const char *file)
 251 {
 252         char *path;
 253         const char *tmp, *tmp2;
 254         int len, flen;
 255         char *fullpath;
 256
 257         if (!file)
 258                 return NULL;
 259
 260         if (*file == '/' || *file == '~' || *file == '$' || !paths || *paths == 0) {
 261                 if (access(file, F_OK) < 0) {
 262                         fullpath = wexpandpath(file);
 263                         if (!fullpath)
 264                                 return NULL;
 265
 266                         if (access(fullpath, F_OK) < 0) {
 267                                 wfree(fullpath);
 268                                 return NULL;
 269                         } else {
 270                                 return fullpath;
 271                         }
 272                 } else {
 273                         return wstrdup(file);
 274                 }
 275         }
 276
 277         flen = strlen(file);
 278         tmp = paths;
 279         while (*tmp) {
 280                 tmp = skipchar(tmp, ':');
 281                 if (*tmp == 0)
 282                         break;
 283                 tmp2 = nextchar(tmp, ':');
 284                 len = tmp2 - tmp;
 285                 path = wmalloc(len + flen + 2);
 286                 path = memcpy(path, tmp, len);
 287                 path[len] = 0;
 288                 if (path[len - 1] != '/' &&
 289                     wstrlcat(path, "/", len + flen + 2) >= len + flen + 2) {
 290                         wfree(path);
 291                         return NULL;
 292                 }
 293
 294                 if (wstrlcat(path, file, len + flen + 2) >= len + flen + 2) {
 295                         wfree(path);
 296                         return NULL;
 297                 }
 298
 299                 fullpath = wexpandpath(path);
 300                 wfree(path);
 301
 302                 if (fullpath) {
 303                         if (access(fullpath, F_OK) == 0) {
 304                                 return fullpath;
 305                         }
 306                         wfree(fullpath);
 307                 }
 308                 tmp = tmp2;
 309         }
 310
 311         return NULL;
 312 }
 313
 314 char *wfindfileinlist(char *const *path_list, const char *file)
 315 {
 316         int i;
 317         char *path;
 318         int len, flen;
 319         char *fullpath;
 320
 321         if (!file)
 322                 return NULL;
 323
 324         if (*file == '/' || *file == '~' || !path_list) {
 325                 if (access(file, F_OK) < 0) {
 326                         fullpath = wexpandpath(file);
 327                         if (!fullpath)
 328                                 return NULL;
 329
 330                         if (access(fullpath, F_OK) < 0) {
 331                                 wfree(fullpath);
 332                                 return NULL;
 333                         } else {
 334                                 return fullpath;
 335                         }
 336                 } else {
 337                         return wstrdup(file);
 338                 }
 339         }
 340
 341         flen = strlen(file);
 342         for (i = 0; path_list[i] != NULL; i++) {
 343                 len = strlen(path_list[i]);
 344                 path = wmalloc(len + flen + 2);
 345                 path = memcpy(path, path_list[i], len);
 346                 path[len] = 0;
 347                 if (wstrlcat(path, "/", len + flen + 2) >= len + flen + 2 ||
 348                     wstrlcat(path, file, len + flen + 2) >= len + flen + 2) {
 349                         wfree(path);
 350                         return NULL;
 351                 }
 352                 /* expand tilde */
 353                 fullpath = wexpandpath(path);
 354                 wfree(path);
 355                 if (fullpath) {
 356                         /* check if file exists */
 357                         if (access(fullpath, F_OK) == 0) {
 358                                 return fullpath;
 359                         }
 360                         wfree(fullpath);
 361                 }
 362         }
 363
 364         return NULL;
 365 }
 366
 367 char *wfindfileinarray(WMPropList *array, const char *file)
 368 {
 369         int i;
 370         char *path;
 371         int len, flen;
 372         char *fullpath;
 373
 374         if (!file)
 375                 return NULL;
 376
 377         if (*file == '/' || *file == '~' || !array) {
 378                 if (access(file, F_OK) < 0) {
 379                         fullpath = wexpandpath(file);
 380                         if (!fullpath)
 381                                 return NULL;
 382
 383                         if (access(fullpath, F_OK) < 0) {
 384                                 wfree(fullpath);
 385                                 return NULL;
 386                         } else {
 387                                 return fullpath;
 388                         }
 389                 } else {
 390                         return wstrdup(file);
 391                 }
 392         }
 393
 394         flen = strlen(file);
 395         for (i = 0; i < WMGetPropListItemCount(array); i++) {
 396                 WMPropList *prop;
 397                 char *p;
 398
 399                 prop = WMGetFromPLArray(array, i);
 400                 if (!prop)
 401                         continue;
 402                 p = WMGetFromPLString(prop);
 403
 404                 len = strlen(p);
 405                 path = wmalloc(len + flen + 2);
 406                 path = memcpy(path, p, len);
 407                 path[len] = 0;
 408                 if (wstrlcat(path, "/", len + flen + 2) >= len + flen + 2 ||
 409                     wstrlcat(path, file, len + flen + 2) >= len + flen + 2) {
 410                         wfree(path);
 411                         return NULL;
 412                 }
 413                 /* expand tilde */
 414                 fullpath = wexpandpath(path);
 415                 wfree(path);
 416                 if (fullpath) {
 417                         /* check if file exists */
 418                         if (access(fullpath, F_OK) == 0) {
 419                                 return fullpath;
 420                         }
 421                         wfree(fullpath);
 422                 }
 423         }
 424         return NULL;
 425 }
 426
 427 int wcopy_file(const char *dest_dir, const char *src_file, const char *dest_file)
 428 {
 429         char *path_dst;
 430         int fd_src, fd_dst;
 431         struct stat stat_src;
 432         mode_t permission_dst;
 433         const size_t buffer_size = 2 * 1024 * 1024;     /* 4MB is a decent start choice to allow the OS to take advantage of modern disk's performance */
 434         char *buffer;   /* The buffer is not created on the stack to avoid possible stack overflow as our buffer is big */
 435
 436  try_again_src:
 437         fd_src = open(src_file, O_RDONLY | O_NOFOLLOW);
 438         if (fd_src == -1) {
 439                 if (errno == EINTR)
 440                         goto try_again_src;
 441                 werror(_("Could not open input file \"%s\": %s"), src_file, strerror(errno));
 442                 return -1;
 443         }
 444
 445         /* Only accept to copy regular files */
 446         if (fstat(fd_src, &stat_src) != 0 || !S_ISREG(stat_src.st_mode)) {
 447                 close(fd_src);
 448                 return -1;
 449         }
 450
 451         path_dst = wstrconcat(dest_dir, dest_file);
 452  try_again_dst:
 453         fd_dst = open(path_dst, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
 454         if (fd_dst == -1) {
 455                 if (errno == EINTR)
 456                         goto try_again_dst;
 457                 werror(_("Could not create target file \"%s\": %s"), path_dst, strerror(errno));
 458                 wfree(path_dst);
 459                 close(fd_src);
 460                 return -1;
 461         }
 462
 463         buffer = malloc(buffer_size);   /* Don't use wmalloc to avoid the memset(0) we don't need */
 464         if (buffer == NULL) {
 465                 werror(_("could not allocate memory for the copy buffer"));
 466                 close(fd_dst);
 467                 goto cleanup_and_return_failure;
 468         }
 469
 470         for (;;) {
 471                 ssize_t size_data;
 472                 const char *write_ptr;
 473                 size_t write_remain;
 474
 475         try_again_read:
 476                 size_data = read(fd_src, buffer, buffer_size);
 477                 if (size_data == 0)
 478                         break; /* End of File have been reached */
 479                 if (size_data < 0) {
 480                         if (errno == EINTR)
 481                                 goto try_again_read;
 482                         werror(_("could not read from file \"%s\": %s"), src_file, strerror(errno));
 483                         close(fd_dst);
 484                         goto cleanup_and_return_failure;
 485                 }
 486
 487                 write_ptr = buffer;
 488                 write_remain = size_data;
 489                 while (write_remain > 0) {
 490                         ssize_t write_done;
 491
 492                 try_again_write:
 493                         write_done = write(fd_dst, write_ptr, write_remain);
 494                         if (write_done < 0) {
 495                                 if (errno == EINTR)
 496                                         goto try_again_write;
 497                                 werror(_("could not write data to file \"%s\": %s"), path_dst, strerror(errno));
 498                                 close(fd_dst);
 499                                 goto cleanup_and_return_failure;
 500                         }
 501                         write_ptr    += write_done;
 502                         write_remain -= write_done;
 503                 }
 504         }
 505
 506         /* Keep only the permission-related part of the field: */
 507         permission_dst = stat_src.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO | S_ISUID | S_ISGID | S_ISVTX);
 508         if (fchmod(fd_dst, permission_dst) != 0)
 509                 wwarning(_("could not set permission 0%03o on file \"%s\": %s"),
 510                          permission_dst, path_dst, strerror(errno));
 511
 512         if (close(fd_dst) != 0) {
 513                 werror(_("could not close the file \"%s\": %s"), path_dst, strerror(errno));
 514         cleanup_and_return_failure:
 515                 free(buffer);
 516                 close(fd_src);
 517                 unlink(path_dst);
 518                 wfree(path_dst);
 519                 return -1;
 520         }
 521
 522         free(buffer);
 523         wfree(path_dst);
 524         close(fd_src);
 525
 526         return 0;
 527 }