lib/search/regex.c

   1 /*
   2    Search text engine.
   3    Regex search
   4
   5    Copyright (C) 2009 The Free Software Foundation, Inc.
   6
   7    Written by:
   8    Slava Zanko <slavazanko@gmail.com>, 2009.
   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 2 of the
  15    License, or (at your option) any later version.
  16
  17    The Midnight Commander is distributed in the hope that it will be
  18    useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  19    of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20    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, write to the Free Software
  24    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  25    MA 02110-1301, USA.
  26  */
  27
  28 #include <config.h>
  29
  30 #include <stdlib.h>
  31
  32 #include "lib/global.h"
  33 #include "lib/strutil.h"
  34
  35 #include "src/strescape.h"
  36 #include "src/charsets.h"
  37
  38 #include "search.h"
  39 #include "internal.h"
  40
  41 /*** global variables ****************************************************************************/
  42
  43 /*** file scope macro definitions ****************************************************************/
  44
  45 /*** file scope type declarations ****************************************************************/
  46
  47 typedef enum {
  48     REPLACE_T_NO_TRANSFORM = 0,
  49     REPLACE_T_UPP_TRANSFORM_CHAR = 1,
  50     REPLACE_T_LOW_TRANSFORM_CHAR = 2,
  51     REPLACE_T_UPP_TRANSFORM = 4,
  52     REPLACE_T_LOW_TRANSFORM = 8
  53 } replace_transform_type_t;
  54
  55 /*** file scope variables ************************************************************************/
  56
  57 /*** file scope functions ************************************************************************/
  58
  59 static gboolean
  60 mc_search__regex_str_append_if_special (GString * copy_to, GString * regex_str, gsize * offset)
  61 {
  62     char *tmp_regex_str;
  63     gsize spec_chr_len;
  64     const char **spec_chr;
  65     const char *special_chars[] = {
  66         "\\s", "\\S",
  67         "\\d", "\\D",
  68         "\\b", "\\B",
  69         "\\w", "\\W",
  70         "\\t", "\\n",
  71         "\\r", "\\f",
  72         "\\a", "\\e",
  73         "\\x", "\\X",
  74         "\\c", "\\C",
  75         "\\l", "\\L",
  76         "\\u", "\\U",
  77         "\\E", "\\Q",
  78         NULL
  79     };
  80     spec_chr = special_chars;
  81
  82     tmp_regex_str = &(regex_str->str[*offset]);
  83
  84     while (*spec_chr) {
  85         spec_chr_len = strlen (*spec_chr);
  86         if (!strncmp (tmp_regex_str, *spec_chr, spec_chr_len)) {
  87             if (!strutils_is_char_escaped (regex_str->str, tmp_regex_str)) {
  88                 if (!strncmp ("\\x", *spec_chr, spec_chr_len)) {
  89                     if (*(tmp_regex_str + spec_chr_len) == '{') {
  90                         while ((spec_chr_len < regex_str->len - *offset)
  91                                && *(tmp_regex_str + spec_chr_len) != '}')
  92                             spec_chr_len++;
  93                         if (*(tmp_regex_str + spec_chr_len) == '}')
  94                             spec_chr_len++;
  95                     } else
  96                         spec_chr_len += 2;
  97                 }
  98                 g_string_append_len (copy_to, tmp_regex_str, spec_chr_len);
  99                 *offset += spec_chr_len;
 100                 return TRUE;
 101             }
 102         }
 103         spec_chr++;
 104     }
 105     return FALSE;
 106
 107 }
 108
 109 /* --------------------------------------------------------------------------------------------- */
 110 static void
 111 mc_search__cond_struct_new_regex_hex_add (const char *charset, GString * str_to,
 112                                           const char *one_char, gsize str_len)
 113 {
 114     GString *upp, *low;
 115     gchar *tmp_str;
 116     gsize loop;
 117
 118     upp = mc_search__toupper_case_str (charset, one_char, str_len);
 119     low = mc_search__tolower_case_str (charset, one_char, str_len);
 120
 121     for (loop = 0; loop < upp->len; loop++) {
 122
 123         if (loop < low->len) {
 124             if (upp->str[loop] == low->str[loop])
 125                 tmp_str = g_strdup_printf ("\\x%02X", (unsigned char) upp->str[loop]);
 126             else
 127                 tmp_str =
 128                     g_strdup_printf ("[\\x%02X\\x%02X]", (unsigned char) upp->str[loop],
 129                                      (unsigned char) low->str[loop]);
 130         } else {
 131             tmp_str = g_strdup_printf ("\\x%02X", (unsigned char) upp->str[loop]);
 132         }
 133         g_string_append (str_to, tmp_str);
 134         g_free (tmp_str);
 135     }
 136     g_string_free (upp, TRUE);
 137     g_string_free (low, TRUE);
 138 }
 139
 140 /* --------------------------------------------------------------------------------------------- */
 141
 142 static void
 143 mc_search__cond_struct_new_regex_accum_append (const char *charset, GString * str_to,
 144                                                GString * str_from)
 145 {
 146     GString *recoded_part;
 147     gchar *one_char;
 148     gsize loop;
 149     gboolean just_letters;
 150
 151     loop = 0;
 152     recoded_part = g_string_new ("");
 153
 154     while (loop < str_from->len) {
 155         one_char =
 156             mc_search__get_one_symbol (charset, &(str_from->str[loop]),
 157                                        (str_from->len - loop > 6) ? 6 : str_from->len - loop,
 158                                        &just_letters);
 159         if (!strlen (one_char)) {
 160             loop++;
 161             continue;
 162         }
 163         if (just_letters) {
 164             mc_search__cond_struct_new_regex_hex_add (charset, recoded_part, one_char,
 165                                                       strlen (one_char));
 166         } else {
 167             g_string_append (recoded_part, one_char);
 168         }
 169         loop += strlen (one_char);
 170         if (!strlen (one_char))
 171             loop++;
 172         g_free (one_char);
 173     }
 174
 175     g_string_append (str_to, recoded_part->str);
 176     g_string_free (recoded_part, TRUE);
 177     g_string_set_size (str_from, 0);
 178 }
 179
 180 /* --------------------------------------------------------------------------------------------- */
 181
 182 static GString *
 183 mc_search__cond_struct_new_regex_ci_str (const char *charset, const char *str, gsize str_len)
 184 {
 185     GString *accumulator, *spec_char, *ret_str;
 186     gsize loop;
 187     GString *tmp;
 188     tmp = g_string_new_len (str, str_len);
 189
 190
 191     ret_str = g_string_new ("");
 192     accumulator = g_string_new ("");
 193     spec_char = g_string_new ("");
 194     loop = 0;
 195
 196     while (loop <= str_len) {
 197         if (mc_search__regex_str_append_if_special (spec_char, tmp, &loop)) {
 198             mc_search__cond_struct_new_regex_accum_append (charset, ret_str, accumulator);
 199             g_string_append_len (ret_str, spec_char->str, spec_char->len);
 200             g_string_set_size (spec_char, 0);
 201             continue;
 202         }
 203
 204         if (tmp->str[loop] == '[' && !strutils_is_char_escaped (tmp->str, &(tmp->str[loop]))) {
 205             mc_search__cond_struct_new_regex_accum_append (charset, ret_str, accumulator);
 206
 207             while (loop < str_len && !(tmp->str[loop] == ']'
 208                                        && !strutils_is_char_escaped (tmp->str,
 209                                                                      &(tmp->str[loop])))) {
 210                 g_string_append_c (ret_str, tmp->str[loop]);
 211                 loop++;
 212
 213             }
 214             g_string_append_c (ret_str, tmp->str[loop]);
 215             loop++;
 216             continue;
 217         }
 218         /*
 219            TODO: handle [ and ]
 220          */
 221         g_string_append_c (accumulator, tmp->str[loop]);
 222         loop++;
 223     }
 224     mc_search__cond_struct_new_regex_accum_append (charset, ret_str, accumulator);
 225
 226     g_string_free (accumulator, TRUE);
 227     g_string_free (spec_char, TRUE);
 228     g_string_free (tmp, TRUE);
 229     return ret_str;
 230 }
 231
 232 /* --------------------------------------------------------------------------------------------- */
 233
 234 static mc_search__found_cond_t
 235 mc_search__regex_found_cond_one (mc_search_t * lc_mc_search, mc_search_regex_t * regex,
 236                                  GString * search_str)
 237 {
 238 #ifdef SEARCH_TYPE_GLIB
 239     GError *error = NULL;
 240
 241     if (!g_regex_match_full
 242         (regex, search_str->str, -1, 0, G_REGEX_MATCH_NEWLINE_ANY, &lc_mc_search->regex_match_info,
 243          &error)) {
 244         g_match_info_free (lc_mc_search->regex_match_info);
 245         lc_mc_search->regex_match_info = NULL;
 246         if (error) {
 247             lc_mc_search->error = MC_SEARCH_E_REGEX;
 248             lc_mc_search->error_str = str_conv_gerror_message (error, _(" Regular expression error "));
 249             g_error_free (error);
 250             return COND__FOUND_ERROR;
 251         }
 252         return COND__NOT_FOUND;
 253     }
 254     lc_mc_search->num_rezults = g_match_info_get_match_count (lc_mc_search->regex_match_info);
 255 #else /* SEARCH_TYPE_GLIB */
 256     lc_mc_search->num_rezults = pcre_exec (regex, lc_mc_search->regex_match_info,
 257                                         search_str->str, search_str->len - 1, 0, 0, lc_mc_search->iovector,
 258                                         MC_SEARCH__NUM_REPLACE_ARGS);
 259     if (lc_mc_search->num_rezults < 0) {
 260         return COND__NOT_FOUND;
 261     }
 262 #endif /* SEARCH_TYPE_GLIB */
 263     return COND__FOUND_OK;
 264
 265 }
 266
 267 /* --------------------------------------------------------------------------------------------- */
 268
 269 static mc_search__found_cond_t
 270 mc_search__regex_found_cond (mc_search_t * lc_mc_search, GString * search_str)
 271 {
 272     gsize loop1;
 273     mc_search_cond_t *mc_search_cond;
 274     mc_search__found_cond_t ret;
 275
 276     for (loop1 = 0; loop1 < lc_mc_search->conditions->len; loop1++) {
 277         mc_search_cond = (mc_search_cond_t *) g_ptr_array_index (lc_mc_search->conditions, loop1);
 278
 279         if (!mc_search_cond->regex_handle)
 280             continue;
 281
 282         ret = mc_search__regex_found_cond_one (lc_mc_search, mc_search_cond->regex_handle, search_str);
 283
 284         if (ret != COND__NOT_FOUND)
 285             return ret;
 286     }
 287     return COND__NOT_ALL_FOUND;
 288 }
 289
 290 /* --------------------------------------------------------------------------------------------- */
 291
 292 static int
 293 mc_search_regex__get_max_num_of_replace_tokens (const gchar * str, gsize len)
 294 {
 295     int max_token = 0;
 296     gsize loop;
 297     for (loop = 0; loop < len - 1; loop++) {
 298         if (str[loop] == '\\' && (str[loop + 1] & (char) 0xf0) == 0x30 /* 0-9 */ ) {
 299             if (strutils_is_char_escaped (str, &str[loop]))
 300                 continue;
 301             if (max_token < str[loop + 1] - '0')
 302                 max_token = str[loop + 1] - '0';
 303             continue;
 304         }
 305         if (str[loop] == '$' && str[loop + 1] == '{') {
 306             gsize tmp_len;
 307             char *tmp_str;
 308             int tmp_token;
 309             if (strutils_is_char_escaped (str, &str[loop]))
 310                 continue;
 311
 312             for (tmp_len = 0;
 313                  loop + tmp_len + 2 < len && (str[loop + 2 + tmp_len] & (char) 0xf0) == 0x30;
 314                  tmp_len++);
 315             if (str[loop + 2 + tmp_len] == '}') {
 316                 tmp_str = g_strndup (&str[loop + 2], tmp_len);
 317                 tmp_token = atoi (tmp_str);
 318                 if (max_token < tmp_token)
 319                     max_token = tmp_token;
 320                 g_free (tmp_str);
 321             }
 322         }
 323     }
 324     return max_token;
 325 }
 326
 327 /* --------------------------------------------------------------------------------------------- */
 328
 329 static char *
 330 mc_search_regex__get_token_by_num (const mc_search_t * lc_mc_search, gsize lc_index)
 331 {
 332     int fnd_start = 0, fnd_end = 0;
 333
 334 #ifdef SEARCH_TYPE_GLIB
 335     g_match_info_fetch_pos (lc_mc_search->regex_match_info, lc_index, &fnd_start, &fnd_end);
 336 #else /* SEARCH_TYPE_GLIB */
 337     fnd_start = lc_mc_search->iovector[lc_index * 2 + 0];
 338     fnd_end = lc_mc_search->iovector[lc_index * 2 + 1];
 339 #endif /* SEARCH_TYPE_GLIB */
 340
 341     if (fnd_end - fnd_start == 0)
 342         return NULL;
 343
 344     return g_strndup (lc_mc_search->regex_buffer->str + fnd_start, fnd_end - fnd_start);
 345
 346 }
 347
 348 /* --------------------------------------------------------------------------------------------- */
 349 static int
 350 mc_search_regex__process_replace_str (const GString * replace_str, const gsize current_pos,
 351                                       gsize * skip_len, replace_transform_type_t * replace_flags)
 352 {
 353     int ret = -1;
 354     char *tmp_str;
 355     const char *curr_str = &(replace_str->str[current_pos]);
 356
 357     if (current_pos > replace_str->len)
 358         return -1;
 359
 360     *skip_len = 0;
 361
 362     if (*curr_str == '$' && *(curr_str + 1) == '{' && (*(curr_str + 2) & (char) 0xf0) == 0x30) {
 363         if (strutils_is_char_escaped (replace_str->str, curr_str)) {
 364             *skip_len = 1;
 365             return -1;
 366         }
 367
 368         for (*skip_len = 0;
 369              current_pos + *skip_len + 2 < replace_str->len
 370              && (*(curr_str + 2 + *skip_len) & (char) 0xf0) == 0x30; (*skip_len)++);
 371
 372         if (*(curr_str + 2 + *skip_len) != '}')
 373             return -1;
 374
 375         tmp_str = g_strndup (curr_str + 2, *skip_len);
 376         if (tmp_str == NULL)
 377             return -1;
 378
 379         ret = atoi (tmp_str);
 380         g_free (tmp_str);
 381
 382         *skip_len += 3;         /* ${} */
 383         return ret;
 384     }
 385
 386     if (*curr_str == '\\') {
 387         if (strutils_is_char_escaped (replace_str->str, curr_str)) {
 388             *skip_len = 1;
 389             return -1;
 390         }
 391
 392         if ((*(curr_str + 1) & (char) 0xf0) == 0x30) {
 393             ret = *(curr_str + 1) - '0';
 394             *skip_len = 2;      /* \\ and one digit */
 395             return ret;
 396         }
 397         ret = -2;
 398         *skip_len += 2;
 399         switch (*(curr_str + 1)) {
 400         case 'U':
 401             *replace_flags |= REPLACE_T_UPP_TRANSFORM;
 402             *replace_flags &= ~REPLACE_T_LOW_TRANSFORM;
 403             break;
 404         case 'u':
 405             *replace_flags |= REPLACE_T_UPP_TRANSFORM_CHAR;
 406             break;
 407         case 'L':
 408             *replace_flags |= REPLACE_T_LOW_TRANSFORM;
 409             *replace_flags &= ~REPLACE_T_UPP_TRANSFORM;
 410             break;
 411         case 'l':
 412             *replace_flags |= REPLACE_T_LOW_TRANSFORM_CHAR;
 413             break;
 414         case 'E':
 415             *replace_flags = REPLACE_T_NO_TRANSFORM;
 416             break;
 417         default:
 418             ret = -1;
 419             break;
 420         }
 421     }
 422     return ret;
 423 }
 424 static void
 425 mc_search_regex__process_append_str (GString * dest_str, const char *from, gsize len,
 426                                      replace_transform_type_t * replace_flags)
 427 {
 428     gsize loop = 0;
 429     gsize char_len;
 430     char *tmp_str;
 431     GString *tmp_string;
 432
 433     if (len == (gsize) -1)
 434         len = strlen (from);
 435
 436     if (*replace_flags == REPLACE_T_NO_TRANSFORM) {
 437         g_string_append_len (dest_str, from, len);
 438         return;
 439     }
 440     while (loop < len) {
 441         tmp_str = mc_search__get_one_symbol (NULL, from + loop, len - loop, NULL);
 442         char_len = strlen (tmp_str);
 443         if (*replace_flags & REPLACE_T_UPP_TRANSFORM_CHAR) {
 444             *replace_flags &= !REPLACE_T_UPP_TRANSFORM_CHAR;
 445             tmp_string = mc_search__toupper_case_str (NULL, tmp_str, char_len);
 446             g_string_append (dest_str, tmp_string->str);
 447             g_string_free (tmp_string, TRUE);
 448
 449         } else if (*replace_flags & REPLACE_T_LOW_TRANSFORM_CHAR) {
 450             *replace_flags &= !REPLACE_T_LOW_TRANSFORM_CHAR;
 451             tmp_string = mc_search__toupper_case_str (NULL, tmp_str, char_len);
 452             g_string_append (dest_str, tmp_string->str);
 453             g_string_free (tmp_string, TRUE);
 454
 455         } else if (*replace_flags & REPLACE_T_UPP_TRANSFORM) {
 456             tmp_string = mc_search__toupper_case_str (NULL, tmp_str, char_len);
 457             g_string_append (dest_str, tmp_string->str);
 458             g_string_free (tmp_string, TRUE);
 459
 460         } else if (*replace_flags & REPLACE_T_LOW_TRANSFORM) {
 461             tmp_string = mc_search__tolower_case_str (NULL, tmp_str, char_len);
 462             g_string_append (dest_str, tmp_string->str);
 463             g_string_free (tmp_string, TRUE);
 464
 465         } else {
 466             g_string_append (dest_str, tmp_str);
 467         }
 468         g_free (tmp_str);
 469         loop += char_len;
 470     }
 471
 472 }
 473
 474 /*** public functions ****************************************************************************/
 475
 476 void
 477 mc_search__cond_struct_new_init_regex (const char *charset, mc_search_t * lc_mc_search,
 478                                        mc_search_cond_t * mc_search_cond)
 479 {
 480     GString *tmp = NULL;
 481 #ifdef SEARCH_TYPE_GLIB
 482     GError *error = NULL;
 483 #else /* SEARCH_TYPE_GLIB */
 484     const char *error;
 485     int erroffset;
 486 #endif /* SEARCH_TYPE_GLIB */
 487
 488     if (!lc_mc_search->is_case_sentitive) {
 489         tmp = g_string_new_len (mc_search_cond->str->str, mc_search_cond->str->len);
 490         g_string_free (mc_search_cond->str, TRUE);
 491         mc_search_cond->str = mc_search__cond_struct_new_regex_ci_str (charset, tmp->str, tmp->len);
 492         g_string_free (tmp, TRUE);
 493     }
 494 #ifdef SEARCH_TYPE_GLIB
 495     mc_search_cond->regex_handle =
 496         g_regex_new (mc_search_cond->str->str, G_REGEX_OPTIMIZE | G_REGEX_RAW | G_REGEX_DOTALL, 0,
 497                      &error);
 498
 499     if (error != NULL) {
 500         lc_mc_search->error = MC_SEARCH_E_REGEX_COMPILE;
 501         lc_mc_search->error_str = str_conv_gerror_message (error, _(" Regular expression error "));
 502         g_error_free (error);
 503         return;
 504     }
 505 #else /* SEARCH_TYPE_GLIB */
 506     mc_search_cond->regex_handle =
 507         pcre_compile (mc_search_cond->str->str, PCRE_EXTRA, &error, &erroffset, NULL);
 508     if (mc_search_cond->regex_handle == NULL) {
 509         lc_mc_search->error = MC_SEARCH_E_REGEX_COMPILE;
 510         lc_mc_search->error_str = g_strdup (error);
 511         return;
 512     }
 513     lc_mc_search->regex_match_info = pcre_study (mc_search_cond->regex_handle, 0, &error);
 514     if (lc_mc_search->regex_match_info == NULL) {
 515         if (error) {
 516             lc_mc_search->error = MC_SEARCH_E_REGEX_COMPILE;
 517             lc_mc_search->error_str = g_strdup (error);
 518             g_free (mc_search_cond->regex_handle);
 519             mc_search_cond->regex_handle = NULL;
 520             return;
 521         }
 522     }
 523 #endif /* SEARCH_TYPE_GLIB */
 524 }
 525
 526 /* --------------------------------------------------------------------------------------------- */
 527
 528 gboolean
 529 mc_search__run_regex (mc_search_t * lc_mc_search, const void *user_data,
 530                       gsize start_search, gsize end_search, gsize * found_len)
 531 {
 532     gsize current_pos, virtual_pos;
 533     int current_chr = 0;
 534     gint start_pos;
 535     gint end_pos;
 536
 537     if (lc_mc_search->regex_buffer != NULL)
 538         g_string_free (lc_mc_search->regex_buffer, TRUE);
 539
 540     lc_mc_search->regex_buffer = g_string_new ("");
 541
 542     virtual_pos = current_pos = start_search;
 543     while (virtual_pos <= end_search) {
 544         g_string_set_size (lc_mc_search->regex_buffer, 0);
 545         lc_mc_search->start_buffer = current_pos;
 546
 547         while (1) {
 548             current_chr = mc_search__get_char (lc_mc_search, user_data, current_pos);
 549             if (current_chr == MC_SEARCH_CB_ABORT)
 550                 break;
 551
 552             current_pos++;
 553
 554             if (current_chr == MC_SEARCH_CB_SKIP)
 555                 continue;
 556
 557             virtual_pos++;
 558
 559             g_string_append_c (lc_mc_search->regex_buffer, (char) current_chr);
 560
 561
 562             if (current_chr == 0 || (char) current_chr == '\n')
 563                 break;
 564
 565             if (virtual_pos > end_search)
 566                 break;
 567
 568         }
 569         switch (mc_search__regex_found_cond (lc_mc_search, lc_mc_search->regex_buffer)) {
 570         case COND__FOUND_OK:
 571 #ifdef SEARCH_TYPE_GLIB
 572             g_match_info_fetch_pos (lc_mc_search->regex_match_info, 0, &start_pos, &end_pos);
 573 #else /* SEARCH_TYPE_GLIB */
 574             start_pos = lc_mc_search->iovector[0];
 575             end_pos = lc_mc_search->iovector[1];
 576 #endif /* SEARCH_TYPE_GLIB */
 577             if (found_len)
 578                 *found_len = end_pos - start_pos;
 579             lc_mc_search->normal_offset = lc_mc_search->start_buffer + start_pos;
 580             return TRUE;
 581             break;
 582         case COND__NOT_ALL_FOUND:
 583             break;
 584         default:
 585             g_string_free (lc_mc_search->regex_buffer, TRUE);
 586             lc_mc_search->regex_buffer = NULL;
 587             return FALSE;
 588             break;
 589         }
 590         if (( lc_mc_search->update_fn != NULL ) &&
 591             ( (lc_mc_search->update_fn) (user_data, current_pos) == MC_SEARCH_CB_ABORT))
 592             current_chr = MC_SEARCH_CB_ABORT;
 593
 594         if (current_chr == MC_SEARCH_CB_ABORT)
 595             break;
 596     }
 597     g_string_free (lc_mc_search->regex_buffer, TRUE);
 598     lc_mc_search->regex_buffer = NULL;
 599     lc_mc_search->error = MC_SEARCH_E_NOTFOUND;
 600
 601     if (current_chr != MC_SEARCH_CB_ABORT)
 602         lc_mc_search->error_str = g_strdup (_(STR_E_NOTFOUND));
 603     else
 604         lc_mc_search->error_str = NULL;
 605
 606     return FALSE;
 607 }
 608
 609 /* --------------------------------------------------------------------------------------------- */
 610 GString *
 611 mc_search_regex_prepare_replace_str (mc_search_t * lc_mc_search, GString * replace_str)
 612 {
 613     GString *ret;
 614     gchar *tmp_str;
 615
 616     int num_replace_tokens, lc_index;
 617     gsize loop;
 618     gsize len = 0;
 619     gchar *prev_str;
 620     replace_transform_type_t replace_flags = REPLACE_T_NO_TRANSFORM;
 621
 622     num_replace_tokens =
 623         mc_search_regex__get_max_num_of_replace_tokens (replace_str->str, replace_str->len);
 624
 625     if (lc_mc_search->num_rezults < 0)
 626         return g_string_new_len (replace_str->str, replace_str->len);
 627
 628     if (num_replace_tokens > lc_mc_search->num_rezults - 1
 629         || num_replace_tokens > MC_SEARCH__NUM_REPLACE_ARGS) {
 630         lc_mc_search->error = MC_SEARCH_E_REGEX_REPLACE;
 631         lc_mc_search->error_str = g_strdup (STR_E_RPL_NOT_EQ_TO_FOUND);
 632         return NULL;
 633     }
 634
 635     ret = g_string_new ("");
 636     prev_str = replace_str->str;
 637     for (loop = 0; loop < replace_str->len - 1; loop++) {
 638         lc_index = mc_search_regex__process_replace_str (replace_str, loop, &len, &replace_flags);
 639
 640         if (lc_index == -1) {
 641             if (len != 0) {
 642                 mc_search_regex__process_append_str (ret, prev_str,
 643                                                      replace_str->str - prev_str + loop,
 644                                                      &replace_flags);
 645                 mc_search_regex__process_append_str (ret, replace_str->str + loop + 1, len - 1,
 646                                                      &replace_flags);
 647                 prev_str = replace_str->str + loop + len;
 648                 loop += len - 1;
 649             }
 650             continue;
 651         }
 652
 653         if (lc_index == -2) {
 654             if (loop)
 655                 mc_search_regex__process_append_str (ret, prev_str,
 656                                                      replace_str->str - prev_str + loop,
 657                                                      &replace_flags);
 658             prev_str = replace_str->str + loop + len;
 659             loop += len - 1;
 660             continue;
 661         }
 662
 663         if (lc_index > lc_mc_search->num_rezults) {
 664             g_string_free (ret, TRUE);
 665             lc_mc_search->error = MC_SEARCH_E_REGEX_REPLACE;
 666             lc_mc_search->error_str = g_strdup_printf (STR_E_RPL_INVALID_TOKEN, lc_index);
 667             return NULL;
 668         }
 669
 670         tmp_str = mc_search_regex__get_token_by_num (lc_mc_search, lc_index);
 671         if (tmp_str == NULL)
 672             continue;
 673
 674         if (loop)
 675             mc_search_regex__process_append_str (ret, prev_str, replace_str->str - prev_str + loop,
 676                                                  &replace_flags);
 677         prev_str = replace_str->str + loop + len;
 678
 679         mc_search_regex__process_append_str (ret, tmp_str, -1, &replace_flags);
 680         g_free (tmp_str);
 681         loop += len - 1;
 682     }
 683     mc_search_regex__process_append_str (ret, prev_str,
 684                                          replace_str->str - prev_str + replace_str->len,
 685                                          &replace_flags);
 686
 687     return ret;
 688 }