Various find & replace improvements

 - Can now enter escape sequences (\n,\t,\x..) into find and replace text.
 - Can now enter regex backreferences using two formats:
   \n or \{n} where n >= 0 e.g. this allows for replace text such as 1\{2}3
 - Can now escape regex backreferences e.g. \\2 results in \2

buffer.c

@@ -1264,7 +1264,8 @@ Status bf_replace_string(Buffer *buffer, size_t replace_length,
 
     if (STATUS_IS_SUCCESS(status)) {
         buffer->is_dirty = 1;
-        status = bf_insert_string(buffer, string, string_length, 1);
+        status = bf_insert_string(buffer, string, string_length,
+                                  advance_cursor);
     }
 
     if (!grouped_changes_started) {
@@ -1275,10 +1276,6 @@ Status bf_replace_string(Buffer *buffer, size_t replace_length,
         return status;
     }
 
-    if (advance_cursor) {
-        bp_advance_to_offset(&buffer->pos, gb_get_point(buffer->data));
-    }
-
     return status;
 }
 

command.c

@@ -80,7 +80,7 @@ static Status cm_buffer_save_as(const CommandArgs *);
 static Status cm_save_file_prompt(Session *, char **file_path_ptr);
 static void cm_generate_find_prompt(const BufferSearch *,
                                     char prompt_text[MAX_CMD_PROMPT_LENGTH]);
-static Status cm_prerpare_search(Session *, const BufferPos *start_pos);
+static Status cm_prepare_search(Session *, const BufferPos *start_pos);
 static Status cm_buffer_find(const CommandArgs *);
 static Status cm_buffer_find_next(const CommandArgs *);
 static Status cm_buffer_toggle_search_direction(const CommandArgs *);
@@ -707,7 +707,7 @@ static void cm_generate_find_prompt(const BufferSearch *search,
              direction, case_sensitive);
 }
 
-static Status cm_prerpare_search(Session *sess, const BufferPos *start_pos)
+static Status cm_prepare_search(Session *sess, const BufferPos *start_pos)
 {
     Buffer *buffer = sess->active_buffer;
 
@@ -737,14 +737,36 @@ static Status cm_prerpare_search(Session *sess, const BufferPos *start_pos)
         return status;
     }
 
-    return bs_reinit(&buffer->search, start_pos, pattern, strlen(pattern));
+    size_t pattern_len = strlen(pattern);
+
+    if (buffer->search.search_type == BST_TEXT) {
+        char *processed_pattern = su_process_string(
+                                      pattern, pattern_len,
+                                      buffer->file_format == FF_WINDOWS,
+                                      &pattern_len);
+
+        if (processed_pattern == NULL) {
+            return st_get_error(ERR_OUT_OF_MEMORY, "Out Of Memory - "
+                                "Unable to process input");
+        } else {
+            pattern = processed_pattern;
+        }
+    }
+
+    status = bs_reinit(&buffer->search, start_pos, pattern, pattern_len);
+
+    if (buffer->search.search_type == BST_TEXT) {
+        free(pattern);
+    }
+
+    return status;
 }
 
 static Status cm_buffer_find(const CommandArgs *cmd_args)
 {
     Session *sess = cmd_args->sess;
 
-    RETURN_IF_FAIL(cm_prerpare_search(sess, NULL));
+    RETURN_IF_FAIL(cm_prepare_search(sess, NULL));
 
     if (pr_prompt_cancelled(sess->prompt)) {
         return STATUS_SUCCESS;
@@ -791,8 +813,15 @@ static Status cm_buffer_find_next(const CommandArgs *cmd_args)
             status = bf_set_bp(buffer, &buffer->search.last_match_pos);
         } else {
             char msg[MAX_MSG_SIZE];
+            const char *pattern = buffer->search.opt.pattern;
+
+            if (list_size(sess->search_history) > 0) {
+                pattern = list_get(sess->search_history,
+                                   list_size(sess->search_history) - 1);
+            }
+
             snprintf(msg, MAX_MSG_SIZE, "Unable to find pattern: \"%s\"",
-                     buffer->search.opt.pattern);
+                     pattern);
             se_add_msg(sess, msg);
         }
     }
@@ -884,12 +913,7 @@ static Status cm_prepare_replace(Session *sess, char **rep_text_ptr,
     *rep_length = strlen(rep_text);
 
     Buffer *buffer = sess->active_buffer;
-    Status status = rp_replace_init(&buffer->search, rep_text, *rep_length);
-
-    if (!STATUS_IS_SUCCESS(status)) {
-        free(rep_text);    
-        return status;
-    }
+    Status status = STATUS_SUCCESS;
 
     if (*rep_text != '\0') {
         status = se_add_replace_to_history(sess, rep_text);
@@ -900,6 +924,18 @@ static Status cm_prepare_replace(Session *sess, char **rep_text_ptr,
         }
     }
 
+    RETURN_IF_FAIL(rp_replace_init(&buffer->search, rep_text, *rep_length,
+                                   buffer->file_format == FF_WINDOWS));
+
+    rep_text = su_process_string(rep_text, *rep_length,
+                                 buffer->file_format == FF_WINDOWS,
+                                 rep_length);
+
+    if (rep_text == NULL) {
+        return st_get_error(ERR_OUT_OF_MEMORY, "Out Of Memory - "
+                            "Unable to process input");
+    }
+
     *rep_text_ptr = rep_text;
 
     return status;
@@ -909,7 +945,7 @@ static Status cm_buffer_replace(const CommandArgs *cmd_args)
 {
     Session *sess = cmd_args->sess;
     Buffer *buffer = sess->active_buffer;
-    RETURN_IF_FAIL(cm_prerpare_search(sess, NULL));
+    RETURN_IF_FAIL(cm_prepare_search(sess, NULL));
 
     if (pr_prompt_cancelled(sess->prompt)) {
         return STATUS_SUCCESS;
@@ -984,7 +1020,9 @@ static Status cm_buffer_replace(const CommandArgs *cmd_args)
             } else if (response == QR_CANCEL) {
                 break;
             } else if (response == QR_YES || response == QR_ALL) {
-                status = rp_replace_current_match(buffer, rep_text, rep_length);
+                size_t actual_rep_length;
+                status = rp_replace_current_match(buffer, rep_text, rep_length,
+                                                  &actual_rep_length);
 
                 if (!STATUS_IS_SUCCESS(status)) {
                     break;
@@ -994,7 +1032,8 @@ static Status cm_buffer_replace(const CommandArgs *cmd_args)
 
                 if (search->opt.forward) {
                     size_t new_offset = buffer->search.last_match_pos.offset;
-                    bp_advance_to_offset(&buffer->pos, new_offset + rep_length);
+                    bp_advance_to_offset(&buffer->pos,
+                                         new_offset + actual_rep_length);
                 }
             }
         }
@@ -1007,15 +1046,24 @@ static Status cm_buffer_replace(const CommandArgs *cmd_args)
         bc_end_grouped_changes(&buffer->changes);
     }
 
+    free(rep_text);
+
     if (!STATUS_IS_SUCCESS(status)) {
         return status;
     }
 
     char msg[MAX_MSG_SIZE];
 
     if (match_num == 0) {
+        const char *pattern = search->opt.pattern;
+
+        if (list_size(sess->search_history) > 0) {
+            pattern = list_get(sess->search_history,
+                               list_size(sess->search_history) - 1);
+        }
+
         snprintf(msg, MAX_MSG_SIZE, "Unable to find pattern \"%s\"",
-                 search->opt.pattern);
+                 pattern);
     } else if (replace_num == 0) {
         snprintf(msg, MAX_MSG_SIZE, "No occurrences replaced");
     } else {

config.mk

@@ -19,7 +19,7 @@ STATIC_SOURCES=wed.c display.c buffer.c util.c input.c session.c    \
 	encoding.c config_parse_util.c gap_buffer.c buffer_pos.c    \
 	text_search.c regex_search.c search.c replace.c undo.c      \
 	file_type.c regex_util.c syntax.c theme.c prompt.c          \
-	prompt_completer.c
+	prompt_completer.c search_util.c
 GENERATED_SOURCES=config_parse.c config_scan.c
 SOURCES=$(STATIC_SOURCES) $(GENERATED_SOURCES)
 

regex_search.h

@@ -22,7 +22,7 @@
 #include <pcre.h>
 #include "status.h"
 #include "buffer_pos.h"
-#include "search_options.h"
+#include "search_util.h"
 
 /* Recommend reading: man pcreapi */
 
@@ -45,27 +45,28 @@
 /* The max number of backreferences that can appear in replace text */
 #define MAX_BACK_REF_OCCURRENCES 100
 
+/* Structure to store each backreference occurence in replace text */
+typedef struct {
+    size_t back_ref_num; /* Backreference number */
+    size_t rep_text_index; /* Starting index in replace string */
+    size_t rep_text_length; /* Backreference length in replace string */
+
+    /* e.g. If the user did a regex find and replace and entered \4 as
+     * the replace text then a BackReference struct would look like:
+     * { 4, 0, 2 }
+     *
+     * 1\{2}3 on the other hand would be:
+     * { 2, 1, 4 } */
+} BackReference;
+
 /* This structure contains backreference data processed from replace text 
  * entered by the user */
 typedef struct {
-    /* Each backreference that occurs in replace text has an entry
-     * in the back_refs array below. Each entry has the following 3 properties
-     * stored in an array:
-     *
-     * 0: backreference number
-     * 1: starting index in replace string
-     * 2: backreference length
-     *
-     * e.g. If the user did a regex find and replace and entered \4 as
-     * the replace text then an entry in back_refs would look like:
-     *
-     * 0: 4
-     * 1: 0
-     * 2: 2 
-     *
-     * This information is stored to allow the backreference to be replaced
-     * with the actual matched text once the search has been performed. */
-    size_t back_refs[MAX_BACK_REF_OCCURRENCES][3];
+    /* Each backreference that occurs in the replace text has an entry
+     * in the back_refs array. This information is stored to allow the 
+     * backreference to be replaced with the actual matched text once
+     * a regex search has been performed. */
+    BackReference back_refs[MAX_BACK_REF_OCCURRENCES];
 
     /* The number of backreference entries in the back_refs array */
     size_t back_ref_occurrences;