contrib/libarchive-2/tar/subst.c

   1 /*-
   2  * Copyright (c) 2008 Joerg Sonnenberger
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "bsdtar_platform.h"
  27 __FBSDID("$FreeBSD: src/usr.bin/tar/subst.c,v 1.4 2008/06/15 10:08:16 kientzle Exp $");
  28
  29 #if HAVE_REGEX_H
  30 #include "bsdtar.h"
  31
  32 #include <errno.h>
  33 #include <regex.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #ifndef REG_BASIC
  38 #define REG_BASIC 0
  39 #endif
  40
  41 struct subst_rule {
  42         struct subst_rule *next;
  43         regex_t re;
  44         char *result;
  45         unsigned int global:1, print:1, symlink:1;
  46 };
  47
  48 struct substitution {
  49         struct subst_rule *first_rule, *last_rule;
  50 };
  51
  52 static void
  53 init_substitution(struct bsdtar *bsdtar)
  54 {
  55         struct substitution *subst;
  56
  57         bsdtar->substitution = subst = malloc(sizeof(*subst));
  58         if (subst == NULL)
  59                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
  60         subst->first_rule = subst->last_rule = NULL;
  61 }
  62
  63 void
  64 add_substitution(struct bsdtar *bsdtar, const char *rule_text)
  65 {
  66         struct subst_rule *rule;
  67         struct substitution *subst;
  68         const char *end_pattern, *start_subst;
  69         char *pattern;
  70         int r;
  71
  72         if ((subst = bsdtar->substitution) == NULL) {
  73                 init_substitution(bsdtar);
  74                 subst = bsdtar->substitution;
  75         }
  76
  77         rule = malloc(sizeof(*rule));
  78         if (rule == NULL)
  79                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
  80         rule->next = NULL;
  81
  82         if (subst->last_rule == NULL)
  83                 subst->first_rule = rule;
  84         else
  85                 subst->last_rule->next = rule;
  86         subst->last_rule = rule;
  87
  88         if (*rule_text == '\0')
  89                 bsdtar_errc(bsdtar, 1, 0, "Empty replacement string");
  90         end_pattern = strchr(rule_text + 1, *rule_text);
  91         if (end_pattern == NULL)
  92                 bsdtar_errc(bsdtar, 1, 0, "Invalid replacement string");
  93
  94         pattern = malloc(end_pattern - rule_text);
  95         if (pattern == NULL)
  96                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
  97         memcpy(pattern, rule_text + 1, end_pattern - rule_text - 1);
  98         pattern[end_pattern - rule_text - 1] = '\0';
  99
 100         if ((r = regcomp(&rule->re, pattern, REG_BASIC)) != 0) {
 101                 char buf[80];
 102                 regerror(r, &rule->re, buf, sizeof(buf));
 103                 bsdtar_errc(bsdtar, 1, 0, "Invalid regular expression: %s", buf);
 104         }
 105         free(pattern);
 106
 107         start_subst = end_pattern + 1;
 108         end_pattern = strchr(start_subst, *rule_text);
 109         if (end_pattern == NULL)
 110                 bsdtar_errc(bsdtar, 1, 0, "Invalid replacement string");
 111
 112         rule->result = malloc(end_pattern - start_subst + 1);
 113         if (rule->result == NULL)
 114                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
 115         memcpy(rule->result, start_subst, end_pattern - start_subst);
 116         rule->result[end_pattern - start_subst] = '\0';
 117
 118         rule->global = 0;
 119         rule->print = 0;
 120         rule->symlink = 0;
 121
 122         while (*++end_pattern) {
 123                 switch (*end_pattern) {
 124                 case 'g':
 125                 case 'G':
 126                         rule->global = 1;
 127                         break;
 128                 case 'p':
 129                 case 'P':
 130                         rule->print = 1;
 131                         break;
 132                 case 's':
 133                 case 'S':
 134                         rule->symlink = 1;
 135                         break;
 136                 default:
 137                         bsdtar_errc(bsdtar, 1, 0, "Invalid replacement flag %c", *end_pattern);
 138                 }
 139         }
 140 }
 141
 142 static void
 143 realloc_strncat(struct bsdtar *bsdtar, char **str, const char *append, size_t len)
 144 {
 145         char *new_str;
 146         size_t old_len;
 147
 148         if (*str == NULL)
 149                 old_len = 0;
 150         else
 151                 old_len = strlen(*str);
 152
 153         new_str = malloc(old_len + len + 1);
 154         if (new_str == NULL)
 155                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
 156         memcpy(new_str, *str, old_len);
 157         memcpy(new_str + old_len, append, len);
 158         new_str[old_len + len] = '\0';
 159         free(*str);
 160         *str = new_str;
 161 }
 162
 163 static void
 164 realloc_strcat(struct bsdtar *bsdtar, char **str, const char *append)
 165 {
 166         char *new_str;
 167         size_t old_len;
 168
 169         if (*str == NULL)
 170                 old_len = 0;
 171         else
 172                 old_len = strlen(*str);
 173
 174         new_str = malloc(old_len + strlen(append) + 1);
 175         if (new_str == NULL)
 176                 bsdtar_errc(bsdtar, 1, errno, "Out of memory");
 177         memcpy(new_str, *str, old_len);
 178         strcpy(new_str + old_len, append);
 179         free(*str);
 180         *str = new_str;
 181 }
 182
 183 int
 184 apply_substitution(struct bsdtar *bsdtar, const char *name, char **result, int symlink_only)
 185 {
 186         const char *path = name;
 187         regmatch_t matches[10];
 188         size_t i, j;
 189         struct subst_rule *rule;
 190         struct substitution *subst;
 191         int c, got_match, print_match;
 192
 193         *result = NULL;
 194
 195         if ((subst = bsdtar->substitution) == NULL)
 196                 return 0;
 197
 198         got_match = 0;
 199         print_match = 0;
 200
 201         for (rule = subst->first_rule; rule != NULL; rule = rule->next) {
 202                 if (symlink_only && !rule->symlink)
 203                         continue;
 204                 if (regexec(&rule->re, name, 10, matches, 0))
 205                         break;
 206
 207                 got_match = 1;
 208                 print_match |= rule->print;
 209                 realloc_strncat(bsdtar, result, name, matches[0].rm_so);
 210
 211                 for (i = 0, j = 0; rule->result[i] != '\0'; ++i) {
 212                         if (rule->result[i] == '~') {
 213                                 realloc_strncat(bsdtar, result, rule->result + j, i - j);
 214                                 realloc_strncat(bsdtar, result, name, matches[0].rm_eo);
 215                                 j = i + 1;
 216                                 continue;
 217                         }
 218                         if (rule->result[i] != '\\')
 219                                 continue;
 220
 221                         ++i;
 222                         c = rule->result[i];
 223                         switch (c) {
 224                         case '~':
 225                         case '\\':
 226                                 realloc_strncat(bsdtar, result, rule->result + j, i - j - 1);
 227                                 j = i;
 228                                 break;
 229                         case '1':
 230                         case '2':
 231                         case '3':
 232                         case '4':
 233                         case '5':
 234                         case '6':
 235                         case '7':
 236                         case '8':
 237                         case '9':
 238                                 realloc_strncat(bsdtar, result, rule->result + j, i - j - 1);
 239                                 if ((size_t)(c - '0') > (size_t)(rule->re.re_nsub)) {
 240                                         free(*result);
 241                                         *result = NULL;
 242                                         return -1;
 243                                 }
 244                                 realloc_strncat(bsdtar, result, name + matches[c - '0'].rm_so, matches[c - '0'].rm_eo - matches[c - '0'].rm_so);
 245                                 j = i + 1;
 246                                 break;
 247                         default:
 248                                 /* Just continue; */
 249                                 break;
 250                         }
 251
 252                 }
 253
 254                 realloc_strcat(bsdtar, result, rule->result + j);
 255
 256                 name += matches[0].rm_eo;
 257
 258                 if (!rule->global)
 259                         break;
 260         }
 261
 262         if (got_match)
 263                 realloc_strcat(bsdtar, result, name);
 264
 265         if (print_match)
 266                 fprintf(stderr, "%s >> %s\n", path, *result);
 267
 268         return got_match;
 269 }
 270
 271 void
 272 cleanup_substitution(struct bsdtar *bsdtar)
 273 {
 274         struct subst_rule *rule;
 275         struct substitution *subst;
 276
 277         if ((subst = bsdtar->substitution) == NULL)
 278                 return;
 279
 280         while ((rule = subst->first_rule) != NULL) {
 281                 subst->first_rule = rule->next;
 282                 free(rule->result);
 283                 free(rule);
 284         }
 285         free(subst);
 286 }
 287 #endif /* HAVE_REGEX_H */