grep/grep-2.5.1-egf-speedup.patch

--- grep-2.5.1/src/search.c	2004-12-14 15:08:58.985159277 +0000
+++ grep-2.5.1/src/search.c	2004-12-14 15:55:21.257729918 +0000
@@ -39,6 +39,9 @@
 #ifdef HAVE_LIBPCRE
 # include <pcre.h>
 #endif
+#ifdef HAVE_LANGINFO_CODESET
+# include <langinfo.h>
+#endif
 
 #define NCHAR (UCHAR_MAX + 1)
 
@@ -70,9 +73,10 @@
    call the regexp matcher at all. */
 static int kwset_exact_matches;
 
-#if defined(MBS_SUPPORT)
-static char* check_multibyte_string PARAMS ((char const *buf, size_t size));
-#endif
+/* UTF-8 encoding allows some optimizations that we can't otherwise
+   assume in a multibyte encoding. */
+static int using_utf8;
+
 static void kwsinit PARAMS ((void));
 static void kwsmusts PARAMS ((void));
 static void Gcompile PARAMS ((char const *, size_t));
@@ -84,6 +88,15 @@
 static size_t Pexecute PARAMS ((char const *, size_t, size_t *, int));
 
 void
+check_utf8 (void)
+{
+#ifdef HAVE_LANGINFO_CODESET
+  if (strcmp (nl_langinfo (CODESET), "UTF-8") == 0)
+    using_utf8 = 1;
+#endif
+}
+
+void
 dfaerror (char const *mesg)
 {
   error (2, 0, mesg);
@@ -141,47 +154,6 @@
     }
 }
 
-#ifdef MBS_SUPPORT
-/* This function allocate the array which correspond to "buf".
-   Then this check multibyte string and mark on the positions which
-   are not singlebyte character nor the first byte of a multibyte
-   character.  Caller must free the array.  */
-static char*
-check_multibyte_string(char const *buf, size_t size)
-{
-  char *mb_properties = xmalloc(size);
-  mbstate_t cur_state;
-  wchar_t wc;
-  int i;
-  memset(&cur_state, 0, sizeof(mbstate_t));
-  memset(mb_properties, 0, sizeof(char)*size);
-  for (i = 0; i < size ;)
-    {
-      size_t mbclen;
-      mbclen = mbrtowc(&wc, buf + i, size - i, &cur_state);
-
-      if (mbclen == (size_t) -1 || mbclen == (size_t) -2 || mbclen == 0)
-	{
-	  /* An invalid sequence, or a truncated multibyte character.
-	     We treat it as a singlebyte character.  */
-	  mbclen = 1;
-	}
-      else if (match_icase)
-	{
-	  if (iswupper((wint_t)wc))
-	    {
-	      wc = towlower((wint_t)wc);
-	      wcrtomb(buf + i, wc, &cur_state);
-	    }
-	}
-      mb_properties[i] = mbclen;
-      i += mbclen;
-    }
-
-  return mb_properties;
-}
-#endif
-
 static void
 Gcompile (char const *pattern, size_t size)
 {
@@ -190,6 +162,7 @@
   size_t total = size;
   char const *motif = pattern;
 
+  check_utf8 ();
   re_set_syntax (RE_SYNTAX_GREP | RE_HAT_LISTS_NOT_NEWLINE | (match_icase ? RE_ICASE : 0));
   dfasyntax (RE_SYNTAX_GREP | RE_HAT_LISTS_NOT_NEWLINE, match_icase, eolbyte);
 
@@ -266,6 +239,7 @@
   size_t total = size;
   char const *motif = pattern;
 
+  check_utf8 ();
   if (strcmp (matcher, "awk") == 0)
     {
       re_set_syntax (RE_SYNTAX_AWK | (match_icase ? RE_ICASE : 0));
@@ -350,18 +324,8 @@
   struct kwsmatch kwsm;
   size_t i, ret_val;
 #ifdef MBS_SUPPORT
-  char *mb_properties = NULL;
-  if (MB_CUR_MAX > 1)
-    {
-      if (match_icase)
-        {
-          char *case_buf = xmalloc(size);
-          memcpy(case_buf, buf, size);
-          buf = case_buf;
-        }
-      if (kwset)
-        mb_properties = check_multibyte_string(buf, size);
-    }
+  mbstate_t mbs;
+  memset (&mbs, '\0', sizeof (mbstate_t));
 #endif /* MBS_SUPPORT */
 
   buflim = buf + size;
@@ -373,18 +337,48 @@
 	  if (kwset)
 	    {
 	      /* Find a possible match using the KWset matcher. */
+#ifdef MBS_SUPPORT
+	      size_t bytes_left = 0;
+#endif /* MBS_SUPPORT */
 	      size_t offset = kwsexec (kwset, beg, buflim - beg, &kwsm);
 	      if (offset == (size_t) -1)
 	        goto failure;
+#ifdef MBS_SUPPORT
+	      if (MB_CUR_MAX > 1 && !using_utf8)
+		{
+		  bytes_left = offset;
+		  while (bytes_left)
+		    {
+		      size_t len = mbrlen (beg, bytes_left, &mbs);
+		      if (len == (size_t) -1 || len == 0)
+			{
+			  /* Incomplete character: treat as single-byte. */
+			  memset (&mbs, '\0', sizeof (mbstate_t));
+			  beg++;
+			  bytes_left--;
+			  continue;
+			}
+
+		      if (len == (size_t) -2)
+			/* Offset points inside multibyte character:
+			 * no good. */
+			break;
+
+		      beg += len;
+		      bytes_left -= len;
+		    }
+		}
+	      else
+#endif /* MBS_SUPPORT */
 	      beg += offset;
 	      /* Narrow down to the line containing the candidate, and
 		 run it through DFA. */
 	      end = memchr(beg, eol, buflim - beg);
 	      end++;
 #ifdef MBS_SUPPORT
-	      if (MB_CUR_MAX > 1 && mb_properties[beg - buf] == 0)
+	      if (MB_CUR_MAX > 1 && bytes_left)
 		continue;
-#endif
+#endif /* MBS_SUPPORT */
 	      while (beg > buf && beg[-1] != eol)
 		--beg;
 	      if (kwsm.index < kwset_exact_matches)
@@ -395,13 +389,47 @@
 	  else
 	    {
 	      /* No good fixed strings; start with DFA. */
+#ifdef MBS_SUPPORT
+	      size_t bytes_left = 0;
+#endif /* MBS_SUPPORT */
 	      size_t offset = dfaexec (&dfa, beg, buflim - beg, &backref);
 	      if (offset == (size_t) -1)
 		break;
 	      /* Narrow down to the line we've found. */
+#ifdef MBS_SUPPORT
+	      if (MB_CUR_MAX > 1 && !using_utf8)
+		{
+		  bytes_left = offset;
+		  while (bytes_left)
+		    {
+		      size_t len = mbrlen (beg, bytes_left, &mbs);
+		      if (len == (size_t) -1 || len == 0)
+			{
+			  /* Incomplete character: treat as single-byte. */
+			  memset (&mbs, '\0', sizeof (mbstate_t));
+			  beg++;
+			  bytes_left--;
+			  continue;
+			}
+
+		      if (len == (size_t) -2)
+			/* Offset points inside multibyte character:
+			 * no good. */
+			break;
+
+		      beg += len;
+		      bytes_left -= len;
+		    }
+		}
+	      else
+#endif /* MBS_SUPPORT */
 	      beg += offset;
 	      end = memchr (beg, eol, buflim - beg);
 	      end++;
+#ifdef MBS_SUPPORT
+	      if (MB_CUR_MAX > 1 && bytes_left)
+		continue;
+#endif /* MBS_SUPPORT */
 	      while (beg > buf && beg[-1] != eol)
 		--beg;
 	    }
@@ -469,15 +497,6 @@
     } /* for (beg = end ..) */
 
  failure:
-#ifdef MBS_SUPPORT
-  if (MB_CUR_MAX > 1)
-    {
-      if (mb_properties)
-	free (mb_properties);
-      if (match_icase)
-	free ((char *) buf);
-    }
-#endif /* MBS_SUPPORT */
   return (size_t) -1;
 
  success_in_beg_and_end:
@@ -486,15 +505,6 @@
   /* FALLTHROUGH */
 
  success_in_start_and_len:
-#ifdef MBS_SUPPORT
-  if (MB_CUR_MAX > 1)
-    {
-      if (mb_properties)
-	free (mb_properties);
-      if (match_icase)
-	free ((char *) buf);
-    }
-#endif /* MBS_SUPPORT */
   *match_size = len;
   return start;
 }
@@ -504,6 +514,7 @@
 {
   char const *beg, *lim, *err;
 
+  check_utf8 ();
   kwsinit ();
   beg = pattern;
   do
@@ -531,17 +542,8 @@
   struct kwsmatch kwsmatch;
   size_t ret_val;
 #ifdef MBS_SUPPORT
-  char *mb_properties = NULL;
-  if (MB_CUR_MAX > 1)
-    {
-      if (match_icase)
-        {
-          char *case_buf = xmalloc(size);
-          memcpy(case_buf, buf, size);
-          buf = case_buf;
-        }
-      mb_properties = check_multibyte_string(buf, size);
-    }
+  mbstate_t mbs;
+  memset (&mbs, '\0', sizeof (mbstate_t));
 #endif /* MBS_SUPPORT */
 
   for (beg = buf; beg <= buf + size; ++beg)
@@ -550,8 +552,33 @@
       if (offset == (size_t) -1)
 	goto failure;
 #ifdef MBS_SUPPORT
-      if (MB_CUR_MAX > 1 && mb_properties[offset+beg-buf] == 0)
-	continue; /* It is a part of multibyte character.  */
+      if (MB_CUR_MAX > 1 && !using_utf8)
+	{
+	  size_t bytes_left = offset;
+	  while (bytes_left)
+	    {
+	      size_t len = mbrlen (beg, bytes_left, &mbs);
+	      if (len == (size_t) -1 || len == 0)
+		{
+		  /* Incomplete character: treat as single-byte. */
+		  memset (&mbs, '\0', sizeof (mbstate_t));
+		  beg++;
+		  bytes_left--;
+		  continue;
+		}
+
+	      if (len == (size_t) -2)
+		/* Offset points inside multibyte character: no good. */
+		break;
+
+	      beg += len;
+	      bytes_left -= len;
+	    }
+
+	  if (bytes_left)
+	    continue;
+	}
+      else
 #endif /* MBS_SUPPORT */
       beg += offset;
       len = kwsmatch.size[0];
@@ -587,6 +614,36 @@
 	          if (offset == -1) {
 	            break; /* Try a different anchor. */
 	          }
+#ifdef MBS_SUPPORT
+		  if (MB_CUR_MAX > 1 && !using_utf8)
+		    {
+		      size_t bytes_left = offset;
+		      while (bytes_left)
+			{
+			  size_t len = mbrlen (beg, bytes_left, &mbs);
+			  if (len == (size_t) -1 || len == 0)
+			    {
+			      /* Incomplete character: treat as single-byte. */
+			      memset (&mbs, '\0', sizeof (mbstate_t));
+			      beg++;
+			      bytes_left--;
+			      continue;
+			    }
+
+			  if (len == (size_t) -2)
+			    /* Offset points inside multibyte character:
+			     * no good. */
+			    break;
+
+			  beg += len;
+			  bytes_left -= len;
+			}
+
+		      if (bytes_left)
+			break; /* Try a different anchor. */
+		    }
+		  else
+#endif /* MBS_SUPPORT */
 	          beg += offset;
 	          len = kwsmatch.size[0];
 	        }
@@ -597,19 +654,31 @@
     }
 
  failure:
+  return -1;
+
+ success:
 #ifdef MBS_SUPPORT
-  if (MB_CUR_MAX > 1)
+  if (MB_CUR_MAX > 1 && !using_utf8)
     {
-      if (match_icase)
-        free((char *) buf);
-      if (mb_properties)
-        free(mb_properties);
+      end = beg + len;
+      while (end < buf + size)
+	{
+	  size_t len = mbrlen (end, buf + size - end, &mbs);
+	  if (len == (size_t) -1 || len == (size_t) -2 || len == 0)
+	    {
+	      memset (&mbs, '\0', sizeof (mbstate_t));
+	      len = 1;
+	    }
+	  if (len == 1 && *end == eol)
+	    break;
+
+	  end += len;
+	}
     }
+  else
 #endif /* MBS_SUPPORT */
-  return -1;
-
- success:
   end = memchr (beg + len, eol, (buf + size) - (beg + len));
+
   end++;
   while (buf < beg && beg[-1] != eol)
     --beg;
@@ -618,15 +687,6 @@
 
  success_in_beg_and_len:
   *match_size = len;
-#ifdef MBS_SUPPORT
-  if (MB_CUR_MAX > 1)
-    {
-      if (mb_properties)
-	free (mb_properties);
-      if (match_icase)
-	free ((char *) buf);
-    }
-#endif /* MBS_SUPPORT */
   return beg - buf;
 }