src/exclist.c

   1 /* Per-directory exclusion files for tar.
   2
   3    Copyright 2014-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GNU tar.
   6
   7    GNU tar is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    GNU tar is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20 #include <system.h>
  21 #include <quotearg.h>
  22 #include <fnmatch.h>
  23 #include <wordsplit.h>
  24 #include "common.h"
  25
  26 typedef void (*add_fn) (struct exclude *, char const *, int, void *);
  27
  28 struct vcs_ignore_file
  29 {
  30   char const *filename;
  31   int flags;
  32   add_fn addfn;
  33   void *(*initfn) (void *);
  34   void *data;
  35 };
  36
  37 static struct vcs_ignore_file *get_vcs_ignore_file (const char *name);
  38 \f
  39 struct excfile
  40 {
  41   struct excfile *next;
  42   int flags;
  43   char name[1];
  44 };
  45
  46 static struct excfile *excfile_head, *excfile_tail;
  47
  48 void
  49 excfile_add (const char *name, int flags)
  50 {
  51   struct excfile *p = xmalloc (sizeof (*p) + strlen (name));
  52   p->next = NULL;
  53   p->flags = flags;
  54   strcpy (p->name, name);
  55   if (excfile_tail)
  56     excfile_tail->next = p;
  57   else
  58     excfile_head = p;
  59   excfile_tail = p;
  60 }
  61
  62 struct exclist
  63 {
  64   struct exclist *next, *prev;
  65   int flags;
  66   struct exclude *excluded;
  67 };
  68
  69 void
  70 info_attach_exclist (struct tar_stat_info *dir)
  71 {
  72   struct excfile *file;
  73   struct exclist *head = NULL, *tail = NULL, *ent;
  74   struct vcs_ignore_file *vcsfile;
  75
  76   if (dir->exclude_list)
  77     return;
  78   for (file = excfile_head; file; file = file->next)
  79     {
  80       if (faccessat (dir ? dir->fd : chdir_fd, file->name, F_OK, 0) == 0)
  81         {
  82           FILE *fp;
  83           struct exclude *ex = NULL;
  84           int fd = subfile_open (dir, file->name, O_RDONLY);
  85           if (fd == -1)
  86             {
  87               open_error (file->name);
  88               continue;
  89             }
  90           fp = fdopen (fd, "r");
  91           if (!fp)
  92             {
  93               ERROR ((0, errno, _("%s: fdopen failed"), file->name));
  94               close (fd);
  95               continue;
  96             }
  97
  98           if (!ex)
  99             ex = new_exclude ();
 100
 101           vcsfile = get_vcs_ignore_file (file->name);
 102
 103           if (vcsfile->initfn)
 104             vcsfile->data = vcsfile->initfn (vcsfile->data);
 105
 106           if (add_exclude_fp (vcsfile->addfn, ex, fp,
 107                               FNM_FILE_NAME|EXCLUDE_WILDCARDS|EXCLUDE_ANCHORED,
 108                               '\n',
 109                               vcsfile->data))
 110             {
 111               int e = errno;
 112               FATAL_ERROR ((0, e, "%s", quotearg_colon (file->name)));
 113             }
 114           fclose (fp);
 115
 116           ent = xmalloc (sizeof (*ent));
 117           ent->excluded = ex;
 118           ent->flags = file->flags == EXCL_DEFAULT
 119                        ? file->flags : vcsfile->flags;
 120           ent->prev = tail;
 121           ent->next = NULL;
 122
 123           if (tail)
 124             tail->next = ent;
 125           else
 126             head = ent;
 127           tail = ent;
 128         }
 129     }
 130   dir->exclude_list = head;
 131 }
 132
 133 void
 134 info_free_exclist (struct tar_stat_info *dir)
 135 {
 136   struct exclist *ep = dir->exclude_list;
 137
 138   while (ep)
 139     {
 140       struct exclist *next = ep->next;
 141       free_exclude (ep->excluded);
 142       free (ep);
 143       ep = next;
 144     }
 145
 146   dir->exclude_list = NULL;
 147 }
 148
 149
 150 /* Return nonzero if file NAME is excluded.  */
 151 bool
 152 excluded_name (char const *name, struct tar_stat_info *st)
 153 {
 154   struct exclist *ep;
 155   const char *rname = NULL;
 156   char *bname = NULL;
 157   bool result;
 158   int nr = 0;
 159
 160   name += FILE_SYSTEM_PREFIX_LEN (name);
 161
 162   /* Try global exclusion list first */
 163   if (excluded_file_name (excluded, name))
 164     return true;
 165
 166   if (!st)
 167     return false;
 168
 169   for (result = false; st && !result; st = st->parent, nr = EXCL_NON_RECURSIVE)
 170     {
 171       for (ep = st->exclude_list; ep; ep = ep->next)
 172         {
 173           if (ep->flags & nr)
 174             continue;
 175           if ((result = excluded_file_name (ep->excluded, name)))
 176             break;
 177
 178           if (!rname)
 179             {
 180               rname = name;
 181               /* Skip leading ./ */
 182               while (*rname == '.' && ISSLASH (rname[1]))
 183                 rname += 2;
 184             }
 185           if ((result = excluded_file_name (ep->excluded, rname)))
 186             break;
 187
 188           if (!bname)
 189             bname = base_name (name);
 190           if ((result = excluded_file_name (ep->excluded, bname)))
 191             break;
 192         }
 193     }
 194
 195   free (bname);
 196
 197   return result;
 198 }
 199 \f
 200 static void
 201 cvs_addfn (struct exclude *ex, char const *pattern, int options, void *data)
 202 {
 203   struct wordsplit ws;
 204   size_t i;
 205
 206   if (wordsplit (pattern, &ws,
 207                  WRDSF_NOVAR | WRDSF_NOCMD | WRDSF_SQUEEZE_DELIMS))
 208     return;
 209   for (i = 0; i < ws.ws_wordc; i++)
 210     add_exclude (ex, ws.ws_wordv[i], options);
 211   wordsplit_free (&ws);
 212 }
 213
 214 static void
 215 git_addfn (struct exclude *ex, char const *pattern, int options, void *data)
 216 {
 217   while (isspace (*pattern))
 218     ++pattern;
 219   if (*pattern == 0 || *pattern == '#')
 220     return;
 221   if (*pattern == '\\' && pattern[1] == '#')
 222     ++pattern;
 223   add_exclude (ex, pattern, options);
 224 }
 225
 226 static void
 227 bzr_addfn (struct exclude *ex, char const *pattern, int options, void *data)
 228 {
 229   while (isspace (*pattern))
 230     ++pattern;
 231   if (*pattern == 0 || *pattern == '#')
 232     return;
 233   if (*pattern == '!')
 234     {
 235       if (*++pattern == '!')
 236         ++pattern;
 237       else
 238         options |= EXCLUDE_INCLUDE;
 239     }
 240   /* FIXME: According to the docs, globbing patterns are rsync-style,
 241             and regexps are perl-style. */
 242   if (strncmp (pattern, "RE:", 3) == 0)
 243     {
 244       pattern += 3;
 245       options &= ~EXCLUDE_WILDCARDS;
 246       options |= EXCLUDE_REGEX;
 247     }
 248   add_exclude (ex, pattern, options);
 249 }
 250
 251 static void *
 252 hg_initfn (void *data)
 253 {
 254   static int hg_options;
 255   int *hgopt = data ? data : &hg_options;
 256   *hgopt = EXCLUDE_REGEX;
 257   return hgopt;
 258 }
 259
 260 static void
 261 hg_addfn (struct exclude *ex, char const *pattern, int options, void *data)
 262 {
 263   int *hgopt = data;
 264   size_t len;
 265
 266   while (isspace (*pattern))
 267     ++pattern;
 268   if (*pattern == 0 || *pattern == '#')
 269     return;
 270   if (strncmp (pattern, "syntax:", 7) == 0)
 271     {
 272       for (pattern += 7; isspace (*pattern); ++pattern)
 273         ;
 274       if (strcmp (pattern, "regexp") == 0)
 275         /* FIXME: Regexps must be perl-style */
 276         *hgopt = EXCLUDE_REGEX;
 277       else if (strcmp (pattern, "glob") == 0)
 278         *hgopt = EXCLUDE_WILDCARDS;
 279       /* Ignore unknown syntax */
 280       return;
 281     }
 282
 283   len = strlen(pattern);
 284   if (pattern[len-1] == '/')
 285     {
 286       char *p;
 287
 288       --len;
 289       p = xmalloc (len+1);
 290       memcpy (p, pattern, len);
 291       p[len] = 0;
 292       pattern = p;
 293       exclude_add_pattern_buffer (ex, p);
 294       options |= FNM_LEADING_DIR|EXCLUDE_ALLOC;
 295     }
 296
 297   add_exclude (ex, pattern,
 298                ((*hgopt == EXCLUDE_REGEX)
 299                 ? (options & ~EXCLUDE_WILDCARDS)
 300                 : (options & ~EXCLUDE_REGEX)) | *hgopt);
 301 }
 302 \f
 303 static struct vcs_ignore_file vcs_ignore_files[] = {
 304   { ".cvsignore", EXCL_NON_RECURSIVE, cvs_addfn, NULL, NULL },
 305   { ".gitignore", 0, git_addfn, NULL, NULL },
 306   { ".bzrignore", 0, bzr_addfn, NULL, NULL },
 307   { ".hgignore",  0, hg_addfn, hg_initfn, NULL },
 308   { NULL, 0, git_addfn, NULL, NULL }
 309 };
 310
 311 static struct vcs_ignore_file *
 312 get_vcs_ignore_file (const char *name)
 313 {
 314   struct vcs_ignore_file *p;
 315
 316   for (p = vcs_ignore_files; p->filename; p++)
 317     if (strcmp (p->filename, name) == 0)
 318       break;
 319
 320   return p;
 321 }
 322 \f
 323 void
 324 exclude_vcs_ignores (void)
 325 {
 326   struct vcs_ignore_file *p;
 327
 328   for (p = vcs_ignore_files; p->filename; p++)
 329     excfile_add (p->filename, EXCL_DEFAULT);
 330 }