lib/serialize.c

   1 /*
   2    Provides a serialize/unserialize functionality for INI-like formats.
   3
   4    Copyright (C) 2011-2017
   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 /*** file scope variables ************************************************************************/
  50
  51 /*** file scope functions ************************************************************************/
  52 /* --------------------------------------------------------------------------------------------- */
  53
  54 static void
  55 G_GNUC_PRINTF (2, 3)
  56 prepend_error_message (GError ** error, const char *format, ...)
  57 {
  58     char *prepend_str;
  59     char *split_str;
  60     va_list ap;
  61
  62     if ((error == NULL) || (*error == NULL))
  63         return;
  64
  65     va_start (ap, format);
  66     prepend_str = g_strdup_vprintf (format, ap);
  67     va_end (ap);
  68
  69     split_str = g_strdup_printf ("%s: %s", prepend_str, (*error)->message);
  70     g_free (prepend_str);
  71     g_free ((*error)->message);
  72     (*error)->message = split_str;
  73 }
  74
  75 /* --------------------------------------------------------------------------------------------- */
  76
  77 static const char *
  78 go_to_end_of_serialized_string (const char *non_serialized_data,
  79                                 const char *already_serialized_part, size_t * offset)
  80 {
  81     size_t calculated_offset;
  82     const char *semi_ptr = strchr (non_serialized_data + 1, SRLZ_DELIM_C);
  83
  84     calculated_offset = (semi_ptr - non_serialized_data) + 1 + strlen (already_serialized_part);
  85     if (calculated_offset >= strlen (non_serialized_data))
  86         return NULL;
  87
  88     non_serialized_data += calculated_offset;
  89     *offset += calculated_offset;
  90
  91     return non_serialized_data;
  92 }
  93
  94 /* --------------------------------------------------------------------------------------------- */
  95 /*** public functions ****************************************************************************/
  96 /* --------------------------------------------------------------------------------------------- */
  97
  98 /**
  99  * Serialize some string object to string
 100  *
 101  * @param prefix prefix for serailization
 102  * @param data data for serialization
 103  * @param error contain pointer to object for handle error code and message
 104  *
 105  * @return serialized data as newly allocated string
 106  */
 107
 108 char *
 109 mc_serialize_str (const char prefix, const char *data, GError ** error)
 110 {
 111     if (data == NULL)
 112     {
 113         g_set_error (error, MC_ERROR, 0, "mc_serialize_str(): Input data is NULL.");
 114         return NULL;
 115     }
 116     return g_strdup_printf ("%c%zu" SRLZ_DELIM_S "%s", prefix, strlen (data), data);
 117 }
 118
 119 /* --------------------------------------------------------------------------------------------- */
 120 /**
 121  * Deserialize string to string object
 122  *
 123  * @param prefix prefix for deserailization
 124  * @param data data for deserialization
 125  * @param error contain pointer to object for handle error code and message
 126  *
 127  * @return newly allocated string
 128  */
 129
 130 #define FUNC_NAME "mc_serialize_str()"
 131 char *
 132 mc_deserialize_str (const char prefix, const char *data, GError ** error)
 133 {
 134     size_t data_len;
 135
 136     if ((data == NULL) || (strlen (data) == 0))
 137     {
 138         g_set_error (error, MC_ERROR, 0, FUNC_NAME ": Input data is NULL or empty.");
 139         return NULL;
 140     }
 141
 142     if (*data != prefix)
 143     {
 144         g_set_error (error, MC_ERROR, 0, FUNC_NAME ": String prefix doesn't equal to '%c'", 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, 0,
 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, 0, 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, 0,
 175                      FUNC_NAME
 176                      ": Specified data length (%zu) is greater than actual data length (%zu)",
 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     GString *buffer;
 200
 201     buffer = g_string_new ("");
 202     groups = mc_config_get_groups (data, NULL);
 203
 204     for (group_iterator = groups; *group_iterator != NULL; group_iterator++)
 205     {
 206         char *serialized_str;
 207         gchar **params, **param_iterator;
 208
 209         serialized_str = mc_serialize_str ('g', *group_iterator, error);
 210         if (serialized_str == NULL)
 211         {
 212             g_string_free (buffer, TRUE);
 213             g_strfreev (groups);
 214             return NULL;
 215         }
 216         g_string_append (buffer, serialized_str);
 217         g_free (serialized_str);
 218
 219         params = mc_config_get_keys (data, *group_iterator, NULL);
 220
 221         for (param_iterator = params; *param_iterator != NULL; param_iterator++)
 222         {
 223             char *value;
 224
 225             serialized_str = mc_serialize_str ('p', *param_iterator, error);
 226             if (serialized_str == NULL)
 227             {
 228                 g_string_free (buffer, TRUE);
 229                 g_strfreev (params);
 230                 g_strfreev (groups);
 231                 return NULL;
 232             }
 233             g_string_append (buffer, serialized_str);
 234             g_free (serialized_str);
 235
 236             value = mc_config_get_string_raw (data, *group_iterator, *param_iterator, "");
 237             serialized_str = mc_serialize_str ('v', value, error);
 238             g_free (value);
 239
 240             if (serialized_str == NULL)
 241             {
 242                 g_string_free (buffer, TRUE);
 243                 g_strfreev (params);
 244                 g_strfreev (groups);
 245                 return NULL;
 246             }
 247
 248             g_string_append (buffer, serialized_str);
 249             g_free (serialized_str);
 250         }
 251
 252         g_strfreev (params);
 253     }
 254     return g_string_free (buffer, FALSE);
 255 }
 256
 257 /* --------------------------------------------------------------------------------------------- */
 258 /**
 259  * Deserialize string to mc_config_t object
 260  *
 261  * @param data data for serialization
 262  * @param error contain pointer to object for handle error code and message
 263  *
 264  * @return newly allocated mc_config_t object
 265  */
 266
 267 #define FUNC_NAME "mc_deserialize_config()"
 268 #define prepend_error_and_exit() { \
 269     prepend_error_message (error, FUNC_NAME " at %zu", current_position + 1); \
 270                 mc_config_deinit (ret_data); \
 271                 return NULL; \
 272 }
 273
 274 mc_config_t *
 275 mc_deserialize_config (const char *data, GError ** error)
 276 {
 277     char *current_group = NULL, *current_param = NULL, *current_value = NULL;
 278     size_t current_position = 0;
 279     mc_config_t *ret_data;
 280     enum automat_status
 281     {
 282         WAIT_GROUP,
 283         WAIT_PARAM,
 284         WAIT_VALUE
 285     } current_status = WAIT_GROUP;
 286
 287     ret_data = mc_config_init (NULL, FALSE);
 288
 289     while (data != NULL)
 290     {
 291         if ((current_status == WAIT_GROUP) && (*data == 'p') && (current_group != NULL))
 292             current_status = WAIT_PARAM;
 293
 294         switch (current_status)
 295         {
 296         case WAIT_GROUP:
 297             g_free (current_group);
 298
 299             current_group = mc_deserialize_str ('g', data, error);
 300             if (current_group == NULL)
 301                 prepend_error_and_exit ();
 302
 303             data = go_to_end_of_serialized_string (data, current_group, &current_position);
 304             current_status = WAIT_PARAM;
 305             break;
 306         case WAIT_PARAM:
 307             g_free (current_param);
 308
 309             current_param = mc_deserialize_str ('p', data, error);
 310             if (current_param == NULL)
 311             {
 312                 g_free (current_group);
 313                 prepend_error_and_exit ();
 314             }
 315
 316             data = go_to_end_of_serialized_string (data, current_param, &current_position);
 317             current_status = WAIT_VALUE;
 318             break;
 319         case WAIT_VALUE:
 320             current_value = mc_deserialize_str ('v', data, error);
 321             if (current_value == NULL)
 322             {
 323                 g_free (current_group);
 324                 g_free (current_param);
 325                 prepend_error_and_exit ();
 326             }
 327             mc_config_set_string (ret_data, current_group, current_param, current_value);
 328
 329             data = go_to_end_of_serialized_string (data, current_value, &current_position);
 330             g_free (current_value);
 331             current_status = WAIT_GROUP;
 332             break;
 333         default:
 334             break;
 335         }
 336     }
 337     g_free (current_group);
 338     g_free (current_param);
 339
 340     return ret_data;
 341 }
 342
 343 #undef FUNC_NAME
 344
 345 /* --------------------------------------------------------------------------------------------- */