lib/util/tiniparser.c

   1 /*
   2  * Trivial smb.conf parsing code
   3  * iniparser compatibility layer.
   4  *
   5  * Copyright Jeremy Allison <jra@samba.org> 2014
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, and the entire permission notice in its entirety,
  12  *    including the disclaimer of warranties.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. The name of the author may not be used to endorse or promote
  17  *    products derived from this software without specific prior
  18  *    written permission.
  19  *
  20  * ALTERNATIVELY, this product may be distributed under the terms of
  21  * the GNU Public License Version 3 or later, in which case the provisions
  22  * of the GPL are required INSTEAD OF the above restrictions.  (This clause is
  23  * necessary due to a potential bad interaction between the GPL and
  24  * the restrictions contained in a BSD-style copyright.)
  25  *
  26  * THIS SOFTWARE IS PROVIDED `AS IS'' AND ANY EXPRESS OR IMPLIED
  27  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  29  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  30  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  31  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  32  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  34  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  36  * OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <stdbool.h>
  42 #include <ctype.h>
  43 #include <errno.h>
  44 #include <string.h>
  45 #include <stddef.h>
  46 #include "tini.h"
  47 #include "tiniparser.h"
  48
  49 struct tiniparser_entry {
  50         struct tiniparser_entry *next_entry;
  51         char *key;
  52         char *value;
  53 };
  54
  55 struct tiniparser_section {
  56         struct tiniparser_section *next_section;
  57         struct tiniparser_entry *entry_list;
  58         char section_name[];
  59 };
  60
  61 struct tiniparser_dictionary {
  62         struct tiniparser_section *section_list;
  63 };
  64
  65 /*
  66  * Find a section from a given key.
  67  * Also return start of subkey.
  68  * Return NULL if section name can't be found,
  69  * if no section name given, or no subkey given.
  70  */
  71
  72 static struct tiniparser_section *find_section(struct tiniparser_dictionary *d,
  73                                         const char *key,
  74                                         const char **subkey)
  75 {
  76         struct tiniparser_section *curr_section;
  77         const char *p;
  78         size_t section_len;
  79
  80         if (key == NULL) {
  81                 return NULL;
  82         }
  83         p = strchr(key, ':');
  84         if (p == NULL) {
  85                 /* No section. */
  86                 return NULL;
  87         }
  88
  89         section_len = p - key;
  90         /* Ensure we have at least one character of section name. */
  91         if (section_len == 0) {
  92                 return NULL;
  93         }
  94         /* Ensure we have at least one character of subkey. */
  95         if (p[1] == '\0') {
  96                 return NULL;
  97         }
  98
  99         for (curr_section = d->section_list;
 100                         curr_section;
 101                         curr_section = curr_section->next_section) {
 102                 /*
 103                  * Check if the key section matches the
 104                  * section name *exactly* (with terminating
 105                  * null after section_len characters.
 106                  */
 107                 if ((strncasecmp(key, curr_section->section_name, section_len) == 0) &&
 108                                 (curr_section->section_name[section_len] == '\0')) {
 109                         *subkey = p+1;
 110                         return curr_section;
 111                 }
 112         }
 113         return NULL;
 114 }
 115
 116 static struct tiniparser_entry *find_entry(struct tiniparser_section *section,
 117                                         const char *key)
 118 {
 119         struct tiniparser_entry *curr_entry;
 120
 121         for (curr_entry = section->entry_list;
 122                         curr_entry;
 123                         curr_entry = curr_entry->next_entry) {
 124                 if (strcasecmp(key,
 125                                 curr_entry->key) == 0) {
 126                         return curr_entry;
 127                 }
 128         }
 129         return NULL;
 130 }
 131
 132 const char *tiniparser_getstring(struct tiniparser_dictionary *d,
 133                         const char *key,
 134                         const char *default_value)
 135 {
 136         struct tiniparser_section *section;
 137         struct tiniparser_entry *entry;
 138         const char *subkey;
 139
 140         section = find_section(d, key, &subkey);
 141         if (section == NULL) {
 142                 return default_value;
 143         }
 144
 145         entry = find_entry(section, subkey);
 146         if (entry == NULL) {
 147                 return default_value;
 148         }
 149
 150         return entry->value;
 151 }
 152
 153
 154 bool tiniparser_getboolean(struct tiniparser_dictionary *d,
 155                         const char *key,
 156                         bool default_value)
 157 {
 158         const char *value = tiniparser_getstring(d, key, NULL);
 159
 160         if (value == NULL) {
 161                 return default_value;
 162         }
 163
 164         switch(value[0]) {
 165                 case '1':
 166                 case 'T':
 167                 case 't':
 168                 case 'y':
 169                 case 'Y':
 170                         return true;
 171                 case '0':
 172                 case 'F':
 173                 case 'f':
 174                 case 'n':
 175                 case 'N':
 176                         return false;
 177                 default:
 178                         break;
 179         }
 180
 181         return default_value;
 182 }
 183
 184 int tiniparser_getint(struct tiniparser_dictionary *d,
 185                         const char *key,
 186                         int default_value)
 187 {
 188         const char *value = tiniparser_getstring(d, key, NULL);
 189
 190         if (value == NULL) {
 191                 return default_value;
 192         }
 193
 194         return (int)strtol(value, NULL, 0);
 195 }
 196
 197 static bool value_parser(const char *key,
 198                         const char *value,
 199                         void *private_data)
 200 {
 201         struct tiniparser_dictionary *d =
 202                 (struct tiniparser_dictionary *)private_data;
 203         struct tiniparser_section *section = d->section_list;
 204         struct tiniparser_entry *entry = NULL;
 205         size_t val_len;
 206         size_t key_len;
 207
 208         if (section == NULL) {
 209                 return false;
 210         }
 211         if (key == NULL) {
 212                 return false;
 213         }
 214         if (value == NULL) {
 215                 return false;
 216         }
 217
 218         key_len = strlen(key) + 1;
 219         val_len = strlen(value) + 1;
 220
 221         entry = find_entry(section, key);
 222         if (entry) {
 223                 /* Replace current value. */
 224                 char *new_val = malloc(val_len);
 225                 if (new_val == NULL) {
 226                         return false;
 227                 }
 228                 memcpy(new_val, value, val_len);
 229                 free(entry->value);
 230                 entry->value = new_val;
 231                 return true;
 232         }
 233
 234         /* Create a new entry. */
 235         entry = malloc(sizeof(struct tiniparser_entry));
 236         if (entry == NULL) {
 237                 return false;
 238         }
 239         entry->key = malloc(key_len);
 240         if (entry->key == NULL) {
 241                 free(entry);
 242                 return false;
 243         }
 244         memcpy(entry->key, key, key_len);
 245
 246         entry->value = malloc(val_len);
 247         if (entry->value == NULL) {
 248                 free(entry->key);
 249                 free(entry);
 250                 return false;
 251         }
 252         memcpy(entry->value, value, val_len);
 253
 254         entry->next_entry = section->entry_list;
 255         section->entry_list = entry;
 256         return true;
 257 }
 258
 259 static bool section_parser(const char *section_name,
 260                         void *private_data)
 261 {
 262         struct tiniparser_section **pp_section;
 263         struct tiniparser_section *new_section;
 264         struct tiniparser_dictionary *d =
 265                 (struct tiniparser_dictionary *)private_data;
 266         size_t section_name_len;
 267
 268         if (section_name == NULL) {
 269                 return false;
 270         }
 271
 272         /* Section names can't contain ':' */
 273         if (strchr(section_name, ':') != NULL) {
 274                 return false;
 275         }
 276
 277         /* Do we already have this section ? */
 278         for (pp_section = &d->section_list;
 279                         *pp_section;
 280                         pp_section = &(*pp_section)->next_section) {
 281                 if (strcasecmp(section_name,
 282                                 (*pp_section)->section_name) == 0) {
 283                         /*
 284                          * Move to the front of the list for
 285                          * value_parser() to find it.
 286                          */
 287
 288                         /* First save current entry. */
 289                         struct tiniparser_section *curr_section = *pp_section;
 290
 291                         /* Now unlink current entry from list. */
 292                         *pp_section = curr_section->next_section;
 293
 294                         /* Make current entry next point to whole list. */
 295                         curr_section->next_section = d->section_list;
 296
 297                         /* And replace list with current entry at start. */
 298                         d->section_list = curr_section;
 299
 300                         return true;
 301                 }
 302         }
 303
 304         section_name_len = strlen(section_name) + 1;
 305
 306         /* Create new section. */
 307         new_section = malloc(
 308                 offsetof(struct tiniparser_section, section_name) +
 309                 section_name_len);
 310         if (new_section == NULL) {
 311                 return false;
 312         }
 313
 314         memcpy(new_section->section_name, section_name, section_name_len);
 315
 316         new_section->entry_list = NULL;
 317
 318         /* Add it to the head of the singly linked list. */
 319         new_section->next_section = d->section_list;
 320         d->section_list = new_section;
 321         return true;
 322 }
 323
 324 struct tiniparser_dictionary *tiniparser_load(const char *filename)
 325 {
 326         bool ret;
 327         struct tiniparser_dictionary *d = NULL;
 328         FILE *fp = fopen(filename, "r");
 329
 330         if (fp == NULL) {
 331                 return NULL;
 332         }
 333
 334         d = malloc(sizeof(struct tiniparser_dictionary));
 335         if (d == NULL) {
 336                 fclose(fp);
 337                 return NULL;
 338         }
 339         d->section_list = NULL;
 340
 341         ret = tini_parse(fp,
 342                         false,
 343                         section_parser,
 344                         value_parser,
 345                         d);
 346         fclose(fp);
 347         if (ret == false) {
 348                 tiniparser_freedict(d);
 349                 d = NULL;
 350         }
 351         return d;
 352 }
 353
 354 void tiniparser_freedict(struct tiniparser_dictionary *d)
 355 {
 356         struct tiniparser_section *curr_section, *next_section;
 357
 358         if (d == NULL) {
 359                 return;
 360         }
 361
 362         for (curr_section = d->section_list;
 363                         curr_section;
 364                         curr_section = next_section) {
 365                 struct tiniparser_entry *curr_entry, *next_entry;
 366
 367                 next_section = curr_section->next_section;
 368
 369                 for (curr_entry = curr_section->entry_list;
 370                                 curr_entry;
 371                                 curr_entry = next_entry) {
 372                         next_entry = curr_entry->next_entry;
 373
 374                         free(curr_entry->key);
 375                         free(curr_entry->value);
 376                         free(curr_entry);
 377                 }
 378                 free(curr_section);
 379         }
 380         free(d);
 381 }