lib/serialize.c

   1 /*
   2    Provides a serialize/unserialize functionality for INI-like formats.
   3
   4    Copyright (C) 2011
   5    The Free Software Foundation, Inc.
   6
   7    Written by:
   8    Slava Zanko <slavazanko@gmail.com>, 2011
   9
  10    This file is part of the Midnight Commander.
  11
  12    The Midnight Commander is free software: you can redistribute it
  13    and/or modify it under the terms of the GNU General Public License as
  14    published by the Free Software Foundation, either version 3 of the License,
  15    or (at your option) any later version.
  16
  17    The Midnight Commander is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20    GNU General Public License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  24  */
  25
  26 /** \file serialize.c
  27  *  \brief Source: serialize/unserialize functionality for INI-like formats.
  28  */
  29
  30 #include <config.h>
  31
  32 #include <string.h>
  33 #include <stdlib.h>
  34 #include <stdarg.h>
  35
  36 #include "lib/global.h"
  37
  38 #include "lib/serialize.h"
  39
  40 /*** global variables ****************************************************************************/
  41
  42 /*** file scope macro definitions ****************************************************************/
  43
  44 #define SRLZ_DELIM_C ':'
  45 #define SRLZ_DELIM_S ":"
  46
  47 /*** file scope type declarations ****************************************************************/
  48
  49 /*** file scope variables ************************************************************************/
  50
  51 /*** file scope functions ************************************************************************/
  52 /* --------------------------------------------------------------------------------------------- */
  53
  54 static void
  55 prepend_error_message (GError ** error, const char *format, ...)
  56 {
  57     char *prepend_str;
  58     char *split_str;
  59     va_list ap;
  60
  61     if ((error == NULL) || (*error == NULL))
  62         return;
  63
  64     va_start (ap, format);
  65     prepend_str = g_strdup_vprintf (format, ap);
  66     va_end (ap);
  67
  68     split_str = g_strdup_printf ("%s: %s", prepend_str, (*error)->message);
  69     g_free (prepend_str);
  70     g_free ((*error)->message);
  71     (*error)->message = split_str;
  72 }
  73
  74 /* --------------------------------------------------------------------------------------------- */
  75
  76 static const char *
  77 go_to_end_of_serialized_string (const char *non_serialized_data,
  78                                 const char *already_serialized_part, size_t * offset)
  79 {
  80     size_t calculated_offset;
  81     const char *semi_ptr = strchr (non_serialized_data + 1, SRLZ_DELIM_C);
  82
  83     calculated_offset = (semi_ptr - non_serialized_data) + 1 + strlen (already_serialized_part);
  84     if (calculated_offset >= strlen (non_serialized_data))
  85         return NULL;
  86
  87     non_serialized_data += calculated_offset;
  88     *offset += calculated_offset;
  89
  90     return non_serialized_data;
  91 }
  92
  93 /* --------------------------------------------------------------------------------------------- */
  94 /*** public functions ****************************************************************************/
  95 /* --------------------------------------------------------------------------------------------- */
  96
  97 /**
  98  * Serialize some string object to string
  99  *
 100  * @param prefix prefix for serailization
 101  * @param data data for serialization
 102  * @param error contain pointer to object for handle error code and message
 103  *
 104  * @return serialized data as newly allocated string
 105  */
 106
 107 char *
 108 mc_serialize_str (const char prefix, const char *data, GError ** error)
 109 {
 110     if (data == NULL)
 111     {
 112         g_set_error (error, MC_ERROR, -1, "mc_serialize_str(): Input data is NULL.");
 113         return NULL;
 114     }
 115     return g_strdup_printf ("%c%zd" SRLZ_DELIM_S "%s", prefix, strlen (data), data);
 116 }
 117
 118 /* --------------------------------------------------------------------------------------------- */
 119 /**
 120  * Deserialize string to string object
 121  *
 122  * @param prefix prefix for deserailization
 123  * @param data data for deserialization
 124  * @param error contain pointer to object for handle error code and message
 125  *
 126  * @return newly allocated string
 127  */
 128
 129 #define FUNC_NAME "mc_serialize_str()"
 130 char *
 131 mc_deserialize_str (const char prefix, const char *data, GError ** error)
 132 {
 133     size_t data_len;
 134
 135     if ((data == NULL) || (strlen (data) == 0))
 136     {
 137         g_set_error (error, MC_ERROR, -1, FUNC_NAME ": Input data is NULL or empty.");
 138         return NULL;
 139     }
 140
 141     if (*data != prefix)
 142     {
 143         g_set_error (error, MC_ERROR, -2, FUNC_NAME ": String prefix doesn't equal to '%c'",
 144                      prefix);
 145         return NULL;
 146     }
 147
 148     {
 149         char buffer[BUF_TINY];
 150         char *semi_ptr;
 151         size_t semi_offset;
 152
 153         semi_ptr = strchr (data + 1, SRLZ_DELIM_C);
 154         if (semi_ptr == NULL)
 155         {
 156             g_set_error (error, MC_ERROR, -3,
 157                          FUNC_NAME ": Length delimiter '%c' doesn't exists", SRLZ_DELIM_C);
 158             return NULL;
 159         }
 160         semi_offset = semi_ptr - (data + 1);
 161         if (semi_offset >= BUF_TINY)
 162         {
 163             g_set_error (error, MC_ERROR, -3, FUNC_NAME ": Too big string length");
 164             return NULL;
 165         }
 166         strncpy (buffer, data + 1, semi_offset);
 167         buffer[semi_offset] = '\0';
 168         data_len = atol (buffer);
 169         data += semi_offset + 2;
 170     }
 171
 172     if (data_len > strlen (data))
 173     {
 174         g_set_error (error, MC_ERROR, -3,
 175                      FUNC_NAME
 176                      ": Specified data length (%zd) is greater than actual data length (%zd)",
 177                      data_len, strlen (data));
 178         return NULL;
 179     }
 180     return g_strndup (data, data_len);
 181 }
 182
 183 #undef FUNC_NAME
 184
 185 /* --------------------------------------------------------------------------------------------- */
 186 /**
 187  * Serialize mc_config_t object to string
 188  *
 189  * @param data data for serialization
 190  * @param error contain pointer to object for handle error code and message
 191  *
 192  * @return serialized data as newly allocated string
 193  */
 194
 195 char *
 196 mc_serialize_config (const mc_config_t * data, GError ** error)
 197 {
 198     gchar **groups, **group_iterator;
 199     size_t group_count;
 200     GString *buffer;
 201
 202     buffer = g_string_new ("");
 203     group_iterator = groups = mc_config_get_groups (data, &group_count);
 204
 205     while (group_count-- != 0)
 206     {
 207         char *serialized_str;
 208         gchar **params, **param_iterator;
 209         size_t param_count;
 210
 211         serialized_str = mc_serialize_str ('g', *group_iterator, error);
 212         if (serialized_str == NULL)
 213         {
 214             g_string_free (buffer, TRUE);
 215             g_strfreev (groups);
 216             return NULL;
 217         }
 218         g_string_append (buffer, serialized_str);
 219         g_free (serialized_str);
 220
 221         param_iterator = params = mc_config_get_keys (data, *group_iterator, &param_count);
 222
 223         while (param_count-- != 0)
 224         {
 225             char *value;
 226             serialized_str = mc_serialize_str ('p', *param_iterator, error);
 227             if (serialized_str == NULL)
 228             {
 229                 g_string_free (buffer, TRUE);
 230                 g_strfreev (params);
 231                 g_strfreev (groups);
 232                 return NULL;
 233             }
 234             g_string_append (buffer, serialized_str);
 235             g_free (serialized_str);
 236
 237             value = mc_config_get_string_raw (data, *group_iterator, *param_iterator, "");
 238             serialized_str = mc_serialize_str ('v', value, error);
 239             g_free (value);
 240
 241             if (serialized_str == NULL)
 242             {
 243                 g_string_free (buffer, TRUE);
 244                 g_strfreev (params);
 245                 g_strfreev (groups);
 246                 return NULL;
 247             }
 248
 249             g_string_append (buffer, serialized_str);
 250             g_free (serialized_str);
 251
 252             param_iterator++;
 253         }
 254
 255         g_strfreev (params);
 256
 257         group_iterator++;
 258     }
 259     return g_string_free (buffer, FALSE);
 260 }
 261
 262 /* --------------------------------------------------------------------------------------------- */
 263 /**
 264  * Deserialize string to mc_config_t object
 265  *
 266  * @param data data for serialization
 267  * @param error contain pointer to object for handle error code and message
 268  *
 269  * @return newly allocated mc_config_t object
 270  */
 271
 272 #define FUNC_NAME "mc_deserialize_config()"
 273 #define prepend_error_and_exit() { \
 274     prepend_error_message (error, FUNC_NAME " at %lu", current_position + 1); \
 275                 mc_config_deinit (ret_data); \
 276                 return NULL; \
 277 }
 278
 279 mc_config_t *
 280 mc_deserialize_config (const char *data, GError ** error)
 281 {
 282     char *current_group = NULL, *current_param = NULL, *current_value = NULL;
 283     size_t current_position = 0;
 284     mc_config_t *ret_data = mc_config_init (NULL);
 285     enum automat_status
 286     {
 287         WAIT_GROUP,
 288         WAIT_PARAM,
 289         WAIT_VALUE
 290     } current_status = WAIT_GROUP;
 291
 292     while (data != NULL)
 293     {
 294         if ((current_status == WAIT_GROUP) && (*data == 'p') && (current_group != NULL))
 295             current_status = WAIT_PARAM;
 296
 297         switch (current_status)
 298         {
 299         case WAIT_GROUP:
 300             g_free (current_group);
 301
 302             current_group = mc_deserialize_str ('g', data, error);
 303             if (current_group == NULL)
 304                 prepend_error_and_exit ();
 305
 306             data = go_to_end_of_serialized_string (data, current_group, &current_position);
 307             current_status = WAIT_PARAM;
 308             break;
 309         case WAIT_PARAM:
 310             g_free (current_param);
 311
 312             current_param = mc_deserialize_str ('p', data, error);
 313             if (current_param == NULL)
 314             {
 315                 g_free (current_group);
 316                 prepend_error_and_exit ();
 317             }
 318
 319             data = go_to_end_of_serialized_string (data, current_param, &current_position);
 320             current_status = WAIT_VALUE;
 321             break;
 322         case WAIT_VALUE:
 323             current_value = mc_deserialize_str ('v', data, error);
 324             if (current_value == NULL)
 325             {
 326                 g_free (current_group);
 327                 g_free (current_param);
 328                 prepend_error_and_exit ();
 329             }
 330             mc_config_set_string (ret_data, current_group, current_param, current_value);
 331
 332             data = go_to_end_of_serialized_string (data, current_value, &current_position);
 333             g_free (current_value);
 334             current_status = WAIT_GROUP;
 335             break;
 336         }
 337     }
 338     g_free (current_group);
 339     g_free (current_param);
 340
 341     return ret_data;
 342 }
 343
 344 #undef FUNC_NAME
 345
 346 /* --------------------------------------------------------------------------------------------- */