wimlib.net Git - wimlib/blob - src/capture_common.c

   1 /*
   2  * capture_common.c - Mostly code to handle excluding paths from capture.
   3  */
   4
   5 /*
   6  * Copyright (C) 2013 Eric Biggers
   7  *
   8  * This file is part of wimlib, a library for working with WIM files.
   9  *
  10  * wimlib is free software; you can redistribute it and/or modify it under the
  11  * terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option)
  13  * any later version.
  14  *
  15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include "config.h"
  26 #endif
  27
  28 #include "wimlib/assert.h"
  29 #include "wimlib/capture.h"
  30 #include "wimlib/error.h"
  31 #include "wimlib/paths.h"
  32
  33 #ifdef __WIN32__
  34 #  include "wimlib/win32.h" /* for fnmatch() equivalent */
  35 #else
  36 #  include <fnmatch.h>
  37 #endif
  38 #include <string.h>
  39
  40
  41 static int
  42 canonicalize_pattern(const tchar *pat, tchar **canonical_pat_ret)
  43 {
  44         tchar *canonical_pat;
  45
  46         if (pat[0] != T('/') && pat[0] != T('\\') &&
  47             pat[0] != T('\0') && pat[1] == T(':'))
  48         {
  49                 /* Pattern begins with drive letter */
  50                 if (pat[2] != T('/') && pat[2] != T('\\')) {
  51                         /* Something like c:file, which is actually a path
  52                          * relative to the current working directory on the c:
  53                          * drive.  We require paths with drive letters to be
  54                          * absolute. */
  55                         ERROR("Invalid path \"%"TS"\"; paths including drive letters "
  56                               "must be absolute!", pat);
  57                         ERROR("Maybe try \"%"TC":/%"TS"\"?",
  58                               pat[0], pat + 2);
  59                         return WIMLIB_ERR_INVALID_CAPTURE_CONFIG;
  60                 }
  61
  62                 WARNING("Pattern \"%"TS"\" starts with a drive letter, which is "
  63                         "being removed.", pat);
  64                 /* Strip the drive letter */
  65                 pat += 2;
  66         }
  67         canonical_pat = canonicalize_fs_path(pat);
  68         if (!canonical_pat)
  69                 return WIMLIB_ERR_NOMEM;
  70         *canonical_pat_ret = canonical_pat;
  71         return 0;
  72 }
  73
  74 static int
  75 copy_and_canonicalize_pattern_list(const struct wimlib_pattern_list *list,
  76                                    struct wimlib_pattern_list *copy)
  77 {
  78         int ret = 0;
  79
  80         copy->pats = CALLOC(list->num_pats, sizeof(list->pats[0]));
  81         if (!copy->pats)
  82                 return WIMLIB_ERR_NOMEM;
  83         copy->num_pats = list->num_pats;
  84         for (size_t i = 0; i < list->num_pats; i++) {
  85                 ret = canonicalize_pattern(list->pats[i], &copy->pats[i]);
  86                 if (ret)
  87                         break;
  88         }
  89         return ret;
  90 }
  91
  92 int
  93 copy_and_canonicalize_capture_config(const struct wimlib_capture_config *config,
  94                                      struct wimlib_capture_config **config_copy_ret)
  95 {
  96         struct wimlib_capture_config *config_copy;
  97         int ret;
  98
  99         config_copy = CALLOC(1, sizeof(struct wimlib_capture_config));
 100         if (!config_copy) {
 101                 ret = WIMLIB_ERR_NOMEM;
 102                 goto out_free_capture_config;
 103         }
 104         ret = copy_and_canonicalize_pattern_list(&config->exclusion_pats,
 105                                                  &config_copy->exclusion_pats);
 106         if (ret)
 107                 goto out_free_capture_config;
 108         ret = copy_and_canonicalize_pattern_list(&config->exclusion_exception_pats,
 109                                                  &config_copy->exclusion_exception_pats);
 110         if (ret)
 111                 goto out_free_capture_config;
 112         *config_copy_ret = config_copy;
 113         goto out;
 114 out_free_capture_config:
 115         free_capture_config(config_copy);
 116 out:
 117         return ret;
 118 }
 119
 120 static void
 121 destroy_pattern_list(struct wimlib_pattern_list *list)
 122 {
 123         for (size_t i = 0; i < list->num_pats; i++)
 124                 FREE(list->pats[i]);
 125         FREE(list->pats);
 126 }
 127
 128 void
 129 free_capture_config(struct wimlib_capture_config *config)
 130 {
 131         if (config) {
 132                 destroy_pattern_list(&config->exclusion_pats);
 133                 destroy_pattern_list(&config->exclusion_exception_pats);
 134                 FREE(config);
 135         }
 136 }
 137
 138 static bool
 139 match_pattern(const tchar *path,
 140               const tchar *path_basename,
 141               const struct wimlib_pattern_list *list)
 142 {
 143         for (size_t i = 0; i < list->num_pats; i++) {
 144
 145                 const tchar *pat = list->pats[i];
 146                 const tchar *string;
 147
 148                 if (*pat == T('/')) {
 149                         /* Absolute path from root of capture */
 150                         string = path;
 151                 } else {
 152                         if (tstrchr(pat, T('/')))
 153                                 /* Relative path from root of capture */
 154                                 string = path + 1;
 155                         else
 156                                 /* A file name pattern */
 157                                 string = path_basename;
 158                 }
 159
 160                 /* Warning: on Windows native builds, fnmatch() calls the
 161                  * replacement function in win32.c. */
 162                 if (fnmatch(pat, string, FNM_PATHNAME | FNM_NOESCAPE
 163                                 #ifdef FNM_CASEFOLD
 164                                         | FNM_CASEFOLD
 165                                 #endif
 166                             ) == 0)
 167                 {
 168                         DEBUG("\"%"TS"\" matches the pattern \"%"TS"\"",
 169                               string, pat);
 170                         return true;
 171                 } else {
 172                         DEBUG2("\"%"TS"\" does not match the pattern \"%"TS"\"",
 173                                string, pat);
 174                 }
 175         }
 176         return false;
 177 }
 178
 179 /* Return true if the image capture configuration file indicates we should
 180  * exclude the filename @path from capture.
 181  *
 182  * If @exclude_prefix is %true, the part of the path up and including the name
 183  * of the directory being captured is not included in the path for matching
 184  * purposes.  This allows, for example, a pattern like /hiberfil.sys to match a
 185  * file /mnt/windows7/hiberfil.sys if we are capturing the /mnt/windows7
 186  * directory.
 187  */
 188 bool
 189 exclude_path(const tchar *path, size_t path_len,
 190              const struct wimlib_capture_config *config, bool exclude_prefix)
 191 {
 192         if (!config)
 193                 return false;
 194         const tchar *basename = path_basename_with_len(path, path_len);
 195         if (exclude_prefix) {
 196                 wimlib_assert(path_len >= config->_prefix_num_tchars);
 197                 if (!tmemcmp(config->_prefix, path, config->_prefix_num_tchars) &&
 198                     path[config->_prefix_num_tchars] == T('/'))
 199                 {
 200                         path += config->_prefix_num_tchars;
 201                 }
 202         }
 203         return match_pattern(path, basename, &config->exclusion_pats) &&
 204                 !match_pattern(path, basename, &config->exclusion_exception_pats);
 205
 206 }