(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 8544a1781a..1490b34b4a 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2004-10-25  Kenichi Handa  <[email protected]>
+
+	* fontset.c (fontset_pattern_regexp): Optimize for the case that
+	PATTERN is full XLFD.
+
 2004-10-24  Kenichi Handa  <[email protected]>
 
 	* regex.h (enum reg_errcode_t): New value REG_ERANGEX.
diff --git a/src/fontset.c b/src/fontset.c
index 960b6fcb34..bccbce8bf4 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 == '?')