fts_compat.c

   1 /*
   2 Copyright (c) 2003 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 FTS*
 128 fts_open(char * const *path_argv, int options,
 129          int (*compar)(const FTSENT **, const FTSENT **))
 130 {
 131     FTS *fts;
 132     DIR *dir;
 133     char *cwd;
 134     int rc;
 135
 136     if(options != FTS_LOGICAL || compar != NULL || path_argv[1] != NULL) {
 137         errno = ENOSYS;
 138         return NULL;
 139     }
 140
 141     dir = opendir(path_argv[0]);
 142     if(dir == NULL)
 143         return NULL;
 144
 145     fts = calloc(sizeof(FTS), 1);
 146     if(fts == NULL) {
 147         int save = errno;
 148         closedir(dir);
 149         errno = save;
 150         return NULL;
 151     }
 152
 153     cwd = getcwd_a();
 154     if(cwd == NULL) {
 155         int save = errno;
 156         free(fts);
 157         closedir(dir);
 158         errno = save;
 159         return NULL;
 160     }
 161
 162     rc = fchdir(dirfd(dir));
 163     if(rc < 0) {
 164         int save = errno;
 165         free(cwd);
 166         free(fts);
 167         closedir(dir);
 168         errno = save;
 169         return NULL;
 170     }
 171
 172     fts->depth = 0;
 173     fts->dir[0] = dir;
 174     fts->cwd0 = cwd;
 175     fts->cwd = strdup(path_argv[0]);
 176     return fts;
 177 }
 178
 179 int
 180 fts_close(FTS *fts)
 181 {
 182     int save = 0;
 183     int rc;
 184
 185     if(fts->ftsent.fts_path) {
 186         free(fts->ftsent.fts_path);
 187         fts->ftsent.fts_path = NULL;
 188     }
 189
 190     if(fts->dname) {
 191         free(fts->dname);
 192         fts->dname = NULL;
 193     }
 194
 195     rc = chdir(fts->cwd0);
 196     if(rc < 0)
 197         save = errno;
 198
 199     while(fts->depth >= 0) {
 200         closedir(fts->dir[fts->depth]);
 201         fts->depth--;
 202     }
 203
 204     free(fts->cwd0);
 205     if(fts->cwd) free(fts->cwd);
 206     free(fts);
 207
 208     if(rc < 0) {
 209         errno = save;
 210         return -1;
 211     }
 212     return 0;
 213 }
 214
 215 FTSENT *
 216 fts_read(FTS *fts)
 217 {
 218     struct dirent *dirent;
 219     int rc;
 220     char *name;
 221     char buf[1024];
 222
 223     if(fts->ftsent.fts_path) {
 224         free(fts->ftsent.fts_path);
 225         fts->ftsent.fts_path = NULL;
 226     }
 227
 228     if(fts->dname) {
 229         free(fts->dname);
 230         fts->dname = NULL;
 231     }
 232
 233  again:
 234     dirent = readdir(fts->dir[fts->depth]);
 235     if(dirent == NULL) {
 236         char *newcwd = NULL;
 237         closedir(fts->dir[fts->depth]);
 238         fts->dir[fts->depth] = NULL;
 239         fts->depth--;
 240         if(fts->depth >= 0) {
 241             fts->dname = basename_a(fts->cwd);
 242             if(fts->dname == NULL)
 243                 goto error;
 244             newcwd = dirname_a(fts->cwd);
 245             if(newcwd == NULL)
 246                 goto error;
 247         }
 248         if(fts->cwd) free(fts->cwd);
 249         fts->cwd = NULL;
 250         if(fts->depth < 0)
 251             return NULL;
 252         rc = fchdir(dirfd(fts->dir[fts->depth]));
 253         if(rc < 0) {
 254             free(newcwd);
 255             goto error;
 256         }
 257         fts->cwd = newcwd;
 258         name = fts->dname;
 259         fts->ftsent.fts_info = FTS_DP;
 260         goto done;
 261     }
 262
 263     name = dirent->d_name;
 264
 265  again2:
 266     rc = stat(name, &fts->stat);
 267     if(rc < 0) {
 268         fts->ftsent.fts_info = FTS_NS;
 269         goto error2;
 270     }
 271
 272     if(S_ISDIR(fts->stat.st_mode)) {
 273         char *newcwd;
 274         DIR *dir;
 275
 276         if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
 277             goto again;
 278
 279         if(fts->depth >= FTS_MAX_DEPTH) {
 280             errno = ENFILE;
 281             goto error;
 282         }
 283         dir = opendir(dirent->d_name);
 284         if(dir == NULL) {
 285             if(errno == EACCES) {
 286                 fts->ftsent.fts_info = FTS_DNR;
 287                 goto error2;
 288             } else
 289                 goto error;
 290         }
 291         newcwd = mkfilename(fts->cwd, dirent->d_name);
 292         rc = fchdir(dirfd(dir));
 293         if(rc < 0) {
 294             free(newcwd);
 295             goto error;
 296         }
 297         free(fts->cwd);
 298         fts->cwd = newcwd;
 299         fts->ftsent.fts_info = FTS_D;
 300         fts->depth++;
 301         fts->dir[fts->depth] = dir;
 302         goto done;
 303     } else if(S_ISREG(fts->stat.st_mode)) {
 304         fts->ftsent.fts_info = FTS_F;
 305         goto done;
 306     } else if(S_ISLNK(fts->stat.st_mode)) {
 307         int rc;
 308         rc = readlink(name, buf, 1024);
 309         if(rc < 0)
 310             goto error;
 311         if(rc >= 1023) {
 312             errno = ENAMETOOLONG;
 313             goto error;
 314         }
 315         buf[rc] = '\0';
 316         name = buf;
 317         if(access(buf, F_OK) >= 0)
 318             goto again2;
 319         fts->ftsent.fts_info = FTS_SLNONE;
 320         goto done;
 321     } else {
 322         fts->ftsent.fts_info = FTS_DEFAULT;
 323         goto done;
 324     }
 325
 326  done:
 327     if(fts->cwd == NULL)
 328         fts->cwd = getcwd_a();
 329     if(fts->cwd == NULL) goto error;
 330     fts->ftsent.fts_path = mkfilename(fts->cwd, name);
 331     if(fts->ftsent.fts_path == NULL) goto error;
 332     fts->ftsent.fts_accpath = name;
 333     fts->ftsent.fts_statp = &fts->stat;
 334     return &fts->ftsent;
 335
 336  error:
 337     fts->ftsent.fts_info = FTS_ERR;
 338  error2:
 339     fts->ftsent.fts_errno = errno;
 340     return &fts->ftsent;
 341 }