fts_compat.c

   1 /*
   2 Copyright (c) 2003-2006 by Juliusz Chroboczek
   3
   4 Permission is hereby granted, free of charge, to any person obtaining a copy
   5 of this software and associated documentation files (the "Software"), to deal
   6 in the Software without restriction, including without limitation the rights
   7 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8 copies of the Software, and to permit persons to whom the Software is
   9 furnished to do so, subject to the following conditions:
  10
  11 The above copyright notice and this permission notice shall be included in
  12 all copies or substantial portions of the Software.
  13
  14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  17 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  20 THE SOFTWARE.
  21 */
  22
  23 /* This file implements just enough of the fts family of functions
  24    to make Polipo happy. */
  25
  26 #include <stdlib.h>
  27 #include <errno.h>
  28 #include <unistd.h>
  29 #include <sys/types.h>
  30 #include <dirent.h>
  31 #include <sys/stat.h>
  32 #include <errno.h>
  33 #include <string.h>
  34
  35 #include "fts_compat.h"
  36
  37 static char *
  38 getcwd_a()
  39 {
  40     char buf[256];
  41     char *ret;
  42     ret = getcwd(buf, 256);
  43     if(ret == NULL)
  44         return NULL;
  45     return strdup(buf);
  46 }
  47
  48 static char *
  49 mkfilename(const char *path, char *filename)
  50 {
  51     int n = strlen(path);
  52     char *buf = malloc(n + 1 + strlen(filename) + 1);
  53     if(buf == NULL)
  54         return NULL;
  55     memcpy(buf, path, n);
  56     if(buf[n - 1] != '/')
  57         buf[n++] = '/';
  58     strcpy(buf + n, filename);
  59     return buf;
  60 }
  61
  62 static int
  63 split(const char *path, int *slash_return, int *dlen, int *blen)
  64 {
  65     int len; int slash;
  66     len = strlen(path);
  67     while(len > 0 && path[len - 1] == '/')
  68         len--;
  69     if(len == 0)
  70         return -1;
  71     slash = len - 1;
  72     while(slash >= 0 && path[slash] != '/')
  73         slash--;
  74
  75     if(slash_return) *slash_return = slash;
  76     if(dlen) *dlen = slash + 1;
  77     if(blen) *blen = len - slash - 1;
  78     return 1;
  79 }
  80
  81 static char *
  82 basename_a(const char *path)
  83 {
  84     int blen, slash;
  85     char *b;
  86     int rc;
  87
  88     rc = split(path, &slash, NULL, &blen);
  89     if(rc < 0 || blen == 0)
  90         return NULL;
  91
  92     b = malloc(blen + 1);
  93     if(b == NULL)
  94         return NULL;
  95     memcpy(b, path + slash + 1, blen);
  96     b[blen] = '\0';
  97     return b;
  98 }
  99
 100 static char *
 101 dirname_a(const char *path)
 102 {
 103     int dlen;
 104     int rc;
 105     char *d;
 106
 107     rc = split(path, NULL, &dlen, NULL);
 108     if(rc < 0)
 109         return NULL;
 110
 111     d = malloc(dlen + 1);
 112     if(d == NULL)
 113         return NULL;
 114     memcpy(d, path, dlen);
 115     d[dlen] = '\0';
 116     return d;
 117 }
 118
 119 #if defined(__svr4__) || defined(SVR4)
 120 static int
 121 dirfd(DIR *dir)
 122 {
 123     return dir->dd_fd;
 124 }
 125 #endif
 126
 127 /*
 128  * Make the directory identified by the argument the current directory.
 129  */
 130 #ifdef MINGW
 131 int
 132 change_to_dir(DIR *dir)
 133 {
 134     errno = ENOSYS;
 135     return -1;
 136 }
 137 #else
 138 int
 139 change_to_dir(DIR *dir)
 140 {
 141     return fchdir(dirfd(dir));
 142 }
 143 #endif
 144
 145 FTS*
 146 fts_open(char * const *path_argv, int options,
 147          int (*compar)(const FTSENT **, const FTSENT **))
 148 {
 149     FTS *fts;
 150     DIR *dir;
 151     char *cwd;
 152     int rc;
 153
 154     if(options != FTS_LOGICAL || compar != NULL || path_argv[1] != NULL) {
 155         errno = ENOSYS;
 156         return NULL;
 157     }
 158
 159     dir = opendir(path_argv[0]);
 160     if(dir == NULL)
 161         return NULL;
 162
 163     fts = calloc(sizeof(FTS), 1);
 164     if(fts == NULL) {
 165         int save = errno;
 166         closedir(dir);
 167         errno = save;
 168         return NULL;
 169     }
 170
 171     cwd = getcwd_a();
 172     if(cwd == NULL) {
 173         int save = errno;
 174         free(fts);
 175         closedir(dir);
 176         errno = save;
 177         return NULL;
 178     }
 179
 180     rc = change_to_dir(dir);
 181     if(rc < 0) {
 182         int save = errno;
 183         free(cwd);
 184         free(fts);
 185         closedir(dir);
 186         errno = save;
 187         return NULL;
 188     }
 189
 190     fts->depth = 0;
 191     fts->dir[0] = dir;
 192     fts->cwd0 = cwd;
 193     fts->cwd = strdup(path_argv[0]);
 194     return fts;
 195 }
 196
 197 int
 198 fts_close(FTS *fts)
 199 {
 200     int save = 0;
 201     int rc;
 202
 203     if(fts->ftsent.fts_path) {
 204         free(fts->ftsent.fts_path);
 205         fts->ftsent.fts_path = NULL;
 206     }
 207
 208     if(fts->dname) {
 209         free(fts->dname);
 210         fts->dname = NULL;
 211     }
 212
 213     rc = chdir(fts->cwd0);
 214     if(rc < 0)
 215         save = errno;
 216
 217     while(fts->depth >= 0) {
 218         closedir(fts->dir[fts->depth]);
 219         fts->depth--;
 220     }
 221
 222     free(fts->cwd0);
 223     if(fts->cwd) free(fts->cwd);
 224     free(fts);
 225
 226     if(rc < 0) {
 227         errno = save;
 228         return -1;
 229     }
 230     return 0;
 231 }
 232
 233 FTSENT *
 234 fts_read(FTS *fts)
 235 {
 236     struct dirent *dirent;
 237     int rc;
 238     char *name;
 239     char buf[1024];
 240
 241     if(fts->ftsent.fts_path) {
 242         free(fts->ftsent.fts_path);
 243         fts->ftsent.fts_path = NULL;
 244     }
 245
 246     if(fts->dname) {
 247         free(fts->dname);
 248         fts->dname = NULL;
 249     }
 250
 251  again:
 252     dirent = readdir(fts->dir[fts->depth]);
 253     if(dirent == NULL) {
 254         char *newcwd = NULL;
 255         closedir(fts->dir[fts->depth]);
 256         fts->dir[fts->depth] = NULL;
 257         fts->depth--;
 258         if(fts->depth >= 0) {
 259             fts->dname = basename_a(fts->cwd);
 260             if(fts->dname == NULL)
 261                 goto error;
 262             newcwd = dirname_a(fts->cwd);
 263             if(newcwd == NULL)
 264                 goto error;
 265         }
 266         if(fts->cwd) free(fts->cwd);
 267         fts->cwd = NULL;
 268         if(fts->depth < 0)
 269             return NULL;
 270         rc = change_to_dir(fts->dir[fts->depth]);
 271         if(rc < 0) {
 272             free(newcwd);
 273             goto error;
 274         }
 275         fts->cwd = newcwd;
 276         name = fts->dname;
 277         fts->ftsent.fts_info = FTS_DP;
 278         goto done;
 279     }
 280
 281     name = dirent->d_name;
 282
 283  again2:
 284     rc = stat(name, &fts->stat);
 285     if(rc < 0) {
 286         fts->ftsent.fts_info = FTS_NS;
 287         goto error2;
 288     }
 289
 290     if(S_ISDIR(fts->stat.st_mode)) {
 291         char *newcwd;
 292         DIR *dir;
 293
 294         if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
 295             goto again;
 296
 297         if(fts->depth >= FTS_MAX_DEPTH) {
 298             errno = ENFILE;
 299             goto error;
 300         }
 301         dir = opendir(dirent->d_name);
 302         if(dir == NULL) {
 303             if(errno == EACCES) {
 304                 fts->ftsent.fts_info = FTS_DNR;
 305                 goto error2;
 306             } else
 307                 goto error;
 308         }
 309         newcwd = mkfilename(fts->cwd, dirent->d_name);
 310         rc = change_to_dir(dir);
 311         if(rc < 0) {
 312             free(newcwd);
 313             goto error;
 314         }
 315         free(fts->cwd);
 316         fts->cwd = newcwd;
 317         fts->ftsent.fts_info = FTS_D;
 318         fts->depth++;
 319         fts->dir[fts->depth] = dir;
 320         goto done;
 321     } else if(S_ISREG(fts->stat.st_mode)) {
 322         fts->ftsent.fts_info = FTS_F;
 323         goto done;
 324 #ifdef S_ISLNK
 325     } else if(S_ISLNK(fts->stat.st_mode)) {
 326         int rc;
 327         rc = readlink(name, buf, 1024);
 328         if(rc < 0)
 329             goto error;
 330         if(rc >= 1023) {
 331             errno = ENAMETOOLONG;
 332             goto error;
 333         }
 334         buf[rc] = '\0';
 335         name = buf;
 336         if(access(buf, F_OK) >= 0)
 337             goto again2;
 338         fts->ftsent.fts_info = FTS_SLNONE;
 339         goto done;
 340 #endif
 341     } else {
 342         fts->ftsent.fts_info = FTS_DEFAULT;
 343         goto done;
 344     }
 345
 346  done:
 347     if(fts->cwd == NULL)
 348         fts->cwd = getcwd_a();
 349     if(fts->cwd == NULL) goto error;
 350     fts->ftsent.fts_path = mkfilename(fts->cwd, name);
 351     if(fts->ftsent.fts_path == NULL) goto error;
 352     fts->ftsent.fts_accpath = name;
 353     fts->ftsent.fts_statp = &fts->stat;
 354     return &fts->ftsent;
 355
 356  error:
 357     fts->ftsent.fts_info = FTS_ERR;
 358  error2:
 359     fts->ftsent.fts_errno = errno;
 360     return &fts->ftsent;
 361 }