vi: make regexp search case-insensitive if ":set ignorecase" is active

Reported by Dan Moinescu <dan@moinescu.net>.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 28 insertions, 40 deletions

diff --git a/editors/vi.c b/editors/vi.c
index 3615ee469..097f309c8 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -1707,65 +1707,53 @@ static char *new_screen(int ro, int co)
 // search for pattern starting at p
 static char *char_search(char *p, const char *pat, int dir, int range)
 {
-        char *q;
         struct re_pattern_buffer preg;
+        const char *err;
+        char *q;
         int i;
         int size;
 
         re_syntax_options = RE_SYNTAX_POSIX_EXTENDED;
-        preg.translate = 0;
-        preg.fastmap = 0;
-        preg.buffer = 0;
-        preg.allocated = 0;
+        if (ignorecase)
+                re_syntax_options = RE_SYNTAX_POSIX_EXTENDED | RE_ICASE;
+
+        memset(&preg, 0, sizeof(preg));
+        err = re_compile_pattern(pat, strlen(pat), &preg);
+        if (err != NULL) {
+                status_line_bold("bad search pattern '%s': %s", pat, err);
+                return p;
+        }
 
         // assume a LIMITED forward search
-        q = next_line(p);
-        q = end_line(q);
         q = end - 1;
-        if (dir == BACK) {
-                q = prev_line(p);
+        if (dir == BACK)
                 q = text;
-        }
-        // count the number of chars to search over, forward or backward
-        size = q - p;
-        if (size < 0)
-                size = p - q;
         // RANGE could be negative if we are searching backwards
         range = q - p;
-
-        q = (char *)re_compile_pattern(pat, strlen(pat), (struct re_pattern_buffer *)&preg);
-        if (q != 0) {
-                // The pattern was not compiled
-                status_line_bold("bad search pattern: '%s': %s", pat, q);
-                i = 0;                  // return p if pattern not compiled
-                goto cs1;
-        }
-
         q = p;
+        size = range;
         if (range < 0) {
+                size = -size;
                 q = p - size;
                 if (q < text)
                         q = text;
         }
         // search for the compiled pattern, preg, in p[]
-        // range < 0-  search backward
-        // range > 0-  search forward
+        // range < 0: search backward
+        // range > 0: search forward
         // 0 < start < size
-        // re_search() < 0  not found or error
-        // re_search() > 0  index of found pattern
-        //            struct pattern    char     int    int    int     struct reg
-        // re_search (*pattern_buffer,  *string, size,  start, range,  *regs)
-        i = re_search(&preg, q, size, 0, range, 0);
-        if (i == -1) {
-                p = 0;
-                i = 0;                  // return NULL if pattern not found
-        }
- cs1:
-        if (dir == FORWARD) {
+        // re_search() < 0: not found or error
+        // re_search() >= 0: index of found pattern
+        //           struct pattern   char     int   int    int    struct reg
+        // re_search(*pattern_buffer, *string, size, start, range, *regs)
+        i = re_search(&preg, q, size, /*start:*/ 0, range, /*struct re_registers*:*/ NULL);
+        regfree(&preg);
+        if (i < 0)
+                return NULL;
+        if (dir == FORWARD)
                 p = p + i;
-        } else {
+        else
                 p = p - i;
-        }
         return p;
 }
 
@@ -1790,7 +1778,7 @@ static char *char_search(char *p, const char *pat, int dir, int range)
 
         len = strlen(pat);
         if (dir == FORWARD) {
-                stop = end - 1; // assume range is p - end-1
+                stop = end - 1; // assume range is p..end-1
                 if (range == LIMITED)
                         stop = next_line(p);    // range is to next line
                 for (start = p; start < stop; start++) {
@@ -1799,7 +1787,7 @@ static char *char_search(char *p, const char *pat, int dir, int range)
                         }
                 }
         } else if (dir == BACK) {
-                stop = text;    // assume range is text - p
+                stop = text;    // assume range is text..p
                 if (range == LIMITED)
                         stop = prev_line(p);    // range is to prev line
                 for (start = p - len; start >= stop; start--) {