lib/serialize.c

   1 /*
   2    Provides a serialize/unserialize functionality for INI-like formats.
   3
   4    Copyright (C) 2011-2023
   5    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 lib/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 /*** forward declarations (file scope functions) *************************************************/
  50
  51 /*** file scope variables ************************************************************************/
  52
  53 /* --------------------------------------------------------------------------------------------- */
  54 /*** file scope functions ************************************************************************/
  55 /* --------------------------------------------------------------------------------------------- */
  56
  57 static void
  58 G_GNUC_PRINTF (2, 3)
  59 prepend_error_message (GError ** error, const char *format, ...)
  60 {
  61     char *prepend_str;
  62     char *split_str;
  63     va_list ap;
  64
  65     if ((error == NULL) || (*error == NULL))
  66         return;
  67
  68     va_start (ap, format);
  69     prepend_str = g_strdup_vprintf (format, ap);
  70     va_end (ap);
  71
  72     split_str = g_strdup_printf ("%s: %s", prepend_str, (*error)->message);
  73     g_free (prepend_str);
  74     g_free ((*error)->message);
  75     (*error)->message = split_str;
  76 }
  77
  78 /* --------------------------------------------------------------------------------------------- */
  79
  80 static const char *
  81 go_to_end_of_serialized_string (const char *non_serialized_data,
  82                                 const char *already_serialized_part, size_t * offset)
  83 {
  84     size_t calculated_offset;
  85     const char *semi_ptr = strchr (non_serialized_data + 1, SRLZ_DELIM_C);
  86
  87     calculated_offset = (semi_ptr - non_serialized_data) + 1 + strlen (already_serialized_part);
  88     if (calculated_offset >= strlen (non_serialized_data))
  89         return NULL;
  90
  91     non_serialized_data += calculated_offset;
  92     *offset += calculated_offset;
  93
  94     return non_serialized_data;
  95 }
  96
  97 /* --------------------------------------------------------------------------------------------- */
  98 /*** public functions ****************************************************************************/
  99 /* --------------------------------------------------------------------------------------------- */
 100
 101 /**
 102  * Serialize some string object to string
 103  *
 104  * @param prefix prefix for serialization
 105  * @param data data for serialization
 106  * @param error contain pointer to object for handle error code and message
 107  *
 108  * @return serialized data as newly allocated string
 109  */
 110
 111 char *
 112 mc_serialize_str (const char prefix, const char *data, GError ** error)
 113 {
 114     if (data == NULL)
 115     {
 116         g_set_error (error, MC_ERROR, 0, "mc_serialize_str(): Input data is NULL.");
 117         return NULL;
 118     }
 119     return g_strdup_printf ("%c%zu" SRLZ_DELIM_S "%s", prefix, strlen (data), data);
 120 }
 121
 122 /* --------------------------------------------------------------------------------------------- */
 123 /**
 124  * Deserialize string to string object
 125  *
 126  * @param prefix prefix for deserailization
 127  * @param data data for deserialization
 128  * @param error contain pointer to object for handle error code and message
 129  *
 130  * @return newly allocated string
 131  */
 132
 133 #define FUNC_NAME "mc_serialize_str()"
 134 char *
 135 mc_deserialize_str (const char prefix, const char *data, GError ** error)
 136 {
 137     size_t data_len;
 138
 139     if ((data == NULL) || (*data == '\0'))
 140     {
 141         g_set_error (error, MC_ERROR, 0, FUNC_NAME ": Input data is NULL or empty.");
 142         return NULL;
 143     }
 144
 145     if (*data != prefix)
 146     {
 147         g_set_error (error, MC_ERROR, 0, FUNC_NAME ": String prefix doesn't equal to '%c'", prefix);
 148         return NULL;
 149     }
 150
 151     {
 152         char buffer[BUF_TINY];
 153         char *semi_ptr;
 154         size_t semi_offset;
 155
 156         semi_ptr = strchr (data + 1, SRLZ_DELIM_C);
 157         if (semi_ptr == NULL)
 158         {
 159             g_set_error (error, MC_ERROR, 0,
 160                          FUNC_NAME ": Length delimiter '%c' doesn't exists", SRLZ_DELIM_C);
 161             return NULL;
 162         }
 163         semi_offset = semi_ptr - (data + 1);
 164         if (semi_offset >= BUF_TINY)
 165         {
 166             g_set_error (error, MC_ERROR, 0, FUNC_NAME ": Too big string length");
 167             return NULL;
 168         }
 169         strncpy (buffer, data + 1, semi_offset);
 170         buffer[semi_offset] = '\0';
 171         data_len = atol (buffer);
 172         data += semi_offset + 2;
 173     }
 174
 175     if (data_len > strlen (data))
 176     {
 177         g_set_error (error, MC_ERROR, 0,
 178                      FUNC_NAME
 179                      ": Specified data length (%zu) is greater than actual data length (%zu)",
 180                      data_len, strlen (data));
 181         return NULL;
 182     }
 183     return g_strndup (data, data_len);
 184 }
 185
 186 #undef FUNC_NAME
 187
 188 /* --------------------------------------------------------------------------------------------- */
 189 /**
 190  * Serialize mc_config_t object to string
 191  *
 192  * @param data data for serialization
 193  * @param error contain pointer to object for handle error code and message
 194  *
 195  * @return serialized data as newly allocated string
 196  */
 197
 198 char *
 199 mc_serialize_config (mc_config_t * data, GError ** error)
 200 {
 201     gchar **groups, **group_iterator;
 202     GString *buffer;
 203
 204     buffer = g_string_new ("");
 205     groups = mc_config_get_groups (data, NULL);
 206
 207     for (group_iterator = groups; *group_iterator != NULL; group_iterator++)
 208     {
 209         char *serialized_str;
 210         gchar **params, **param_iterator;
 211
 212         serialized_str = mc_serialize_str ('g', *group_iterator, error);
 213         if (serialized_str == NULL)
 214         {
 215             g_string_free (buffer, TRUE);
 216             g_strfreev (groups);
 217             return NULL;
 218         }
 219         g_string_append (buffer, serialized_str);
 220         g_free (serialized_str);
 221
 222         params = mc_config_get_keys (data, *group_iterator, NULL);
 223
 224         for (param_iterator = params; *param_iterator != NULL; param_iterator++)
 225         {
 226             char *value;
 227
 228             serialized_str = mc_serialize_str ('p', *param_iterator, error);
 229             if (serialized_str == NULL)
 230             {
 231                 g_string_free (buffer, TRUE);
 232                 g_strfreev (params);
 233                 g_strfreev (groups);
 234                 return NULL;
 235             }
 236             g_string_append (buffer, serialized_str);
 237             g_free (serialized_str);
 238
 239             value = mc_config_get_string_raw (data, *group_iterator, *param_iterator, "");
 240             serialized_str = mc_serialize_str ('v', value, error);
 241             g_free (value);
 242
 243             if (serialized_str == NULL)
 244             {
 245                 g_string_free (buffer, TRUE);
 246                 g_strfreev (params);
 247                 g_strfreev (groups);
 248                 return NULL;
 249             }
 250
 251             g_string_append (buffer, serialized_str);
 252             g_free (serialized_str);
 253         }
 254
 255         g_strfreev (params);
 256     }
 257
 258     g_strfreev (groups);
 259
 260     return g_string_free (buffer, FALSE);
 261 }
 262
 263 /* --------------------------------------------------------------------------------------------- */
 264 /**
 265  * Deserialize string to mc_config_t object
 266  *
 267  * @param data data for serialization
 268  * @param error contain pointer to object for handle error code and message
 269  *
 270  * @return newly allocated mc_config_t object
 271  */
 272
 273 #define FUNC_NAME "mc_deserialize_config()"
 274 #define prepend_error_and_exit() { \
 275     prepend_error_message (error, FUNC_NAME " at %zu", current_position + 1); \
 276                 mc_config_deinit (ret_data); \
 277                 return NULL; \
 278 }
 279
 280 mc_config_t *
 281 mc_deserialize_config (const char *data, GError ** error)
 282 {
 283     char *current_group = NULL, *current_param = NULL, *current_value = NULL;
 284     size_t current_position = 0;
 285     mc_config_t *ret_data;
 286     enum automat_status
 287     {
 288         WAIT_GROUP,
 289         WAIT_PARAM,
 290         WAIT_VALUE
 291     } current_status = WAIT_GROUP;
 292
 293     ret_data = mc_config_init (NULL, FALSE);
 294
 295     while (data != NULL)
 296     {
 297         if ((current_status == WAIT_GROUP) && (*data == 'p') && (current_group != NULL))
 298             current_status = WAIT_PARAM;
 299
 300         switch (current_status)
 301         {
 302         case WAIT_GROUP:
 303             g_free (current_group);
 304
 305             current_group = mc_deserialize_str ('g', data, error);
 306             if (current_group == NULL)
 307                 prepend_error_and_exit ();
 308
 309             data = go_to_end_of_serialized_string (data, current_group, &current_position);
 310             current_status = WAIT_PARAM;
 311             break;
 312         case WAIT_PARAM:
 313             g_free (current_param);
 314
 315             current_param = mc_deserialize_str ('p', data, error);
 316             if (current_param == NULL)
 317             {
 318                 g_free (current_group);
 319                 prepend_error_and_exit ();
 320             }
 321
 322             data = go_to_end_of_serialized_string (data, current_param, &current_position);
 323             current_status = WAIT_VALUE;
 324             break;
 325         case WAIT_VALUE:
 326             current_value = mc_deserialize_str ('v', data, error);
 327             if (current_value == NULL)
 328             {
 329                 g_free (current_group);
 330                 g_free (current_param);
 331                 prepend_error_and_exit ();
 332             }
 333             mc_config_set_string (ret_data, current_group, current_param, current_value);
 334
 335             data = go_to_end_of_serialized_string (data, current_value, &current_position);
 336             g_free (current_value);
 337             current_status = WAIT_GROUP;
 338             break;
 339         default:
 340             break;
 341         }
 342     }
 343     g_free (current_group);
 344     g_free (current_param);
 345
 346     return ret_data;
 347 }
 348
 349 #undef FUNC_NAME
 350
 351 /* --------------------------------------------------------------------------------------------- */