(fontset_pattern_regexp): Optimize for the case that

PATTERN is full XLFD.

2 files changed, 27 insertions, 4 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 8544a1781af..1490b34b4a9 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2004-10-25  Kenichi Handa  <handa@m17n.org>
+
+        * fontset.c (fontset_pattern_regexp): Optimize for the case that
+        PATTERN is full XLFD.
+
 2004-10-24  Kenichi Handa  <handa@m17n.org>
 
         * regex.h (enum reg_errcode_t): New value REG_ERANGEX.
diff --git a/src/fontset.c b/src/fontset.c
index 960b6fcb34b..bccbce8bf45 100644
--- a/src/fontset.c
+++ b/src/fontset.c
@@ -789,16 +789,34 @@ fontset_pattern_regexp (pattern)
       || strcmp (SDATA (pattern), CACHED_FONTSET_NAME))
     {
       /* We must at first update the cached data.  */
-      char *regex = (char *) alloca (SCHARS (pattern) * 2 + 3);
-      char *p0, *p1 = regex;
+      char *regex, *p0, *p1;
+      int ndashes = 0, nstars = 0;
+      
+      for (p0 = SDATA (pattern); *p0; p0++)
+        {
+          if (*p0 == '-')
+            ndashes++;
+          else if (*p0 == '*')
+            nstars++;
+        }
+
+      /* If PATTERN is not full XLFD we conert "*" to ".*".  Otherwise
+         we convert "*" to "[^-]*" which is much faster in regular
+         expression matching.  */
+      if (ndashes < 14)
+        p1 = regex = (char *) alloca (SBYTES (pattern) + 2 * nstars + 1);
+      else
+        p1 = regex = (char *) alloca (SBYTES (pattern) + 5 * nstars + 1);
 
-      /* Convert "*" to ".*", "?" to ".".  */
       *p1++ = '^';
       for (p0 = (char *) SDATA (pattern); *p0; p0++)
         {
           if (*p0 == '*')
             {
-              *p1++ = '.';
+              if (ndashes < 14)
+                *p1++ = '.';
+              else
+                *p1++ = '[', *p1++ = '^', *p1++ = '-', *p1++ = ']';
               *p1++ = '*';
             }
           else if (*p0 == '?')