fix search/replace misbehaviors for good (I hope)

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@1598 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

diff --git a/ChangeLog b/ChangeLog
index 59825ec5e0ae0ff03d92b60589ecaa08bb82aae8..d3fcc6bb6795e781d45bf794620ac097dead7beb 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -32,11 +32,12 @@ CVS code -
        - Allow WHEREIS_NEXT_KEY to be used in view mode. (DLR)
 - search.c:
   findnextstr(), do_replace_loop()
-       - Fix potential infinite loops when doing certain forward regex
-         replacements, where we end up either perpetually adding to the
-         end of one line (e. g. replace "$" with anything non-blank) or
-         not moving at all (e. g. replace "^" or "^$" with anything
-         blank). (DLR; found by Mike Frysinger and DLR)
+       - Fix potential infinite loops and other misbehavior when doing
+         certain zero-length regex replacements ("^", "$", and "^$").
+         Add a no_sameline parameter to findnextstr(), and set it in
+         the calls in do_replace_loop() when such regexes are found, so
+         that such regexes are only found once per line. (DLR; found by
+         Mike Frysinger and DLR)
 - winio.c:
   get_accepted_kbinput()
        - Translate Ctrl-8 into NANO_DELETE_KEY, since it apparently is

diff --git a/src/proto.h b/src/proto.h
index ddf08cc844836350ea7743a6b89b7a36423cc6d5..ea59974d391d68b83e9f3bed75d9b8aedb6ec8a3 100644 (file)
--- a/src/proto.h
+++ b/src/proto.h
@@ -363,7 +363,7 @@ int search_init(int replacing);
 int is_whole_word(int curr_pos, const char *datastr, const char *searchword);
 filestruct *findnextstr(int quiet, int bracket_mode,
                        const filestruct *begin, int beginx,
-                       const char *needle, int no_same_loc);
+                       const char *needle, int no_sameline);
 int do_search(void);
 int do_research(void);
 void replace_abort(void);

diff --git a/src/search.c b/src/search.c
index ce587de9e359ca1772e0f85c7f3760f7c18b974b..cbfa29861a30a51f81f679f770ecdb1e7063afc5 100644 (file)
--- a/src/search.c
+++ b/src/search.c
@@ -247,7 +247,7 @@ int is_whole_word(int curr_pos, const char *datastr, const char *searchword)
 
 filestruct *findnextstr(int quiet, int bracket_mode,
                        const filestruct *begin, int beginx,
-                       const char *needle, int no_same_loc)
+                       const char *needle, int no_sameline)
 {
     filestruct *fileptr = current;
     const char *searchstr, *rev_start = NULL, *found = NULL;
@@ -266,11 +266,11 @@ filestruct *findnextstr(int quiet, int bracket_mode,
        searchstr = &fileptr->data[current_x_find];
 
        /* Look for needle in searchstr.  Keep going until we find it
-        * and, if no_same_loc is set, until it isn't the one at
-        * current[current_x].  If we don't find it, we'll end up at
-        * current[current_x] regardless of whether no_same_loc is
+        * and, if no_sameline is set, until it isn't on the current
+        * line.  If we don't find it, we'll end up at
+        * current[current_x] regardless of whether no_sameline is
         * set. */
-       while ((found = strstrwrapper(searchstr, needle, rev_start, current_x_find)) == NULL || (no_same_loc && fileptr == current && current_x_find == current_x)) {
+       while ((found = strstrwrapper(searchstr, needle, rev_start, current_x_find)) == NULL || (no_sameline && fileptr == current)) {
 
            /* finished processing file, get out */
            if (search_last_line) {
@@ -325,11 +325,11 @@ filestruct *findnextstr(int quiet, int bracket_mode,
        searchstr = fileptr->data;
 
        /* Look for needle in searchstr.  Keep going until we find it
-        * and, if no_same_loc is set, until it isn't the one at
-        * current[current_x].  If we don't find it, we'll end up at
-        * current[current_x] regardless of whether no_same_loc is
+        * and, if no_sameline is set, until it isn't on the current
+        * line.  If we don't find it, we'll end up at
+        * current[current_x] regardless of whether no_sameline is
         * set. */
-       while ((found = strstrwrapper(searchstr, needle, rev_start, current_x_find)) == NULL || (no_same_loc && fileptr == current && current_x_find == current_x)) {
+       while ((found = strstrwrapper(searchstr, needle, rev_start, current_x_find)) == NULL || (no_sameline && fileptr == current)) {
 
            /* finished processing file, get out */
            if (search_last_line) {
@@ -618,8 +618,8 @@ int do_replace_loop(const char *prevanswer, const filestruct *begin,
 {
     int replaceall = 0, numreplaced = -1;
 #ifdef HAVE_REGEX_H
-    /* The special case regex flags. */
-    int old_bol = 0, old_eol = 0;
+    /* The starting-line match and zero-length regex flags. */
+    int beginline = 0, caretdollar = 0;
 #endif
     filestruct *fileptr = NULL;
     char *copy;
@@ -646,37 +646,35 @@ int do_replace_loop(const char *prevanswer, const filestruct *begin,
     while (1) {
        size_t match_len;
 
-#ifdef HAVE_REGEX_H
-       /* Check the special case regex flags.  If the last (forward,
-        * zero-length) regex replace left us at the beginning or end of
-        * the line as it was before replacement, move to the beginning
-        * or end of the line as it is now. */
-       if (old_bol)
-           current_x = 0;
-       if (old_eol)
-           current_x = strlen(current->data);
-#endif
-
        /* Sweet optimization by Rocco here. */
        fileptr = findnextstr(fileptr || replaceall || search_last_line,
                FALSE, begin, *beginx, prevanswer,
 #ifdef HAVE_REGEX_H
-               old_bol || old_eol
+               /* We should find a zero-length regex only once per
+                * line.  If the caretdollar flag is set, it means that
+                * the last search found one on the beginning line, so we
+                * should skip over the beginning line when doing this
+                * search. */
+               caretdollar
 #else
                0
 #endif
                );
 
 #ifdef HAVE_REGEX_H
-       /* If either of the special case regex flags are set and we're
-        * back where we started, it means we've wrapped around, so
+       /* If the caretdollar flag is set, we've found a match on the
+        * beginning line already, and we're still on the beginning line
+        * after the search, it means that we've wrapped around, so
         * we're done. */
-       if ((old_bol || old_eol) && fileptr == begin && current_x == *beginx)
+       if (caretdollar && beginline && fileptr == begin)
            fileptr = NULL;
-       /* Otherwise, reset the flags and continue. */
+       /* Otherwise, set the beginline flag if we've found a match on
+        * the beginning line, reset the caretdollar flag, and
+        * continue. */
        else {
-           old_bol = 0;
-           old_eol = 0;
+           if (fileptr == begin)
+               beginline = 1;
+           caretdollar = 0;
        }
 #endif
 
@@ -720,6 +718,13 @@ int do_replace_loop(const char *prevanswer, const filestruct *begin,
            curs_set(1);
        }
 
+#ifdef HAVE_REGEX_H
+       /* Set the caretdollar flag if we're doing a zero-length regex
+        * replace (such as "^", "$", or "^$"). */
+       if (ISSET(USE_REGEXP) && match_len == 0)
+           caretdollar = 1;
+#endif
+
        if (*i > 0 || replaceall) {     /* Yes, replace it!!!! */
            long length_change;
            size_t match_len;
@@ -763,24 +768,9 @@ int do_replace_loop(const char *prevanswer, const filestruct *begin,
             * text, so searching will resume after the replacement
             * text.  Note that current_x might be set to -1 here. */
 #ifndef NANO_SMALL
-           if (!ISSET(REVERSE_SEARCH)) {
-#endif
-#ifdef HAVE_REGEX_H
-               /* Set the special case regex flags if we're at the
-                * beginning or end of the line before a (forward,
-                * zero-length) regex replace.  Note that they can both
-                * be set if we're replacing the magicline. */
-               if (ISSET(USE_REGEXP) && match_len == 0) {
-                   if (current_x <= 0)
-                       old_bol = 1;
-                   if (current_x == strlen(current->data))
-                       old_eol = 1;
-               }
+           if (!ISSET(REVERSE_SEARCH))
 #endif
                current_x += match_len + length_change - 1;
-#ifndef NANO_SMALL
-           }
-#endif
 
            /* Cleanup. */
            totsize += length_change;