X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=lib%2Fts_bm.c;h=9e66ee4020e9085a5cde0c84bf18516335c691da;hp=2cc79112ecc39fc2c945047b67e1c1ac4e67723f;hb=76a67ec6fb79ff3570dcb5342142c16098299911;hpb=8082e4ed0a61da347f1c7f210493c4e9e55c8cd0

diff --git a/lib/ts_bm.c b/lib/ts_bm.c
index 2cc79112..9e66ee4 100644
--- a/lib/ts_bm.c
+++ b/lib/ts_bm.c
@@ -35,11 +35,11 @@
  *   matchings spread over multiple fragments, then go BM.
  */
 
-#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/string.h>
+#include <linux/ctype.h>
 #include <linux/textsearch.h>
 
 /* Alphabet size, use ASCII */
@@ -64,7 +64,8 @@ static unsigned int bm_find(struct ts_config *conf, struct ts_state *state)
 	struct ts_bm *bm = ts_config_priv(conf);
 	unsigned int i, text_len, consumed = state->offset;
 	const u8 *text;
-	int shift = bm->patlen, bs;
+	int shift = bm->patlen - 1, bs;
+	const u8 icase = conf->flags & TS_IGNORECASE;
 
 	for (;;) {
 		text_len = conf->get_next_block(consumed, &text, conf, state);
@@ -76,7 +77,9 @@ static unsigned int bm_find(struct ts_config *conf, struct ts_state *state)
 			DEBUGP("Searching in position %d (%c)\n", 
 				shift, text[shift]);
 			for (i = 0; i < bm->patlen; i++) 
-			     if (text[shift-i] != bm->pattern[bm->patlen-1-i])
+				if ((icase ? toupper(text[shift-i])
+				    : text[shift-i])
+					!= bm->pattern[bm->patlen-1-i])
 				     goto next;
 
 			/* London calling... */
@@ -94,43 +97,57 @@ next:			bs = bm->bad_shift[text[shift-i]];
 	return UINT_MAX;
 }
 
-static void compute_prefix_tbl(struct ts_bm *bm, const u8 *pattern,
-			       unsigned int len)
+static int subpattern(u8 *pattern, int i, int j, int g)
 {
-	int i, j, ended, l[ASIZE];
+	int x = i+g-1, y = j+g-1, ret = 0;
+
+	while(pattern[x--] == pattern[y--]) {
+		if (y < 0) {
+			ret = 1;
+			break;
+		}
+		if (--g == 0) {
+			ret = pattern[i-1] != pattern[j-1];
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static void compute_prefix_tbl(struct ts_bm *bm, int flags)
+{
+	int i, j, g;
 
 	for (i = 0; i < ASIZE; i++)
-		bm->bad_shift[i] = len;
-	for (i = 0; i < len - 1; i++)
-		bm->bad_shift[pattern[i]] = len - 1 - i;
+		bm->bad_shift[i] = bm->patlen;
+	for (i = 0; i < bm->patlen - 1; i++) {
+		bm->bad_shift[bm->pattern[i]] = bm->patlen - 1 - i;
+		if (flags & TS_IGNORECASE)
+			bm->bad_shift[tolower(bm->pattern[i])]
+			    = bm->patlen - 1 - i;
+	}
 
 	/* Compute the good shift array, used to match reocurrences 
 	 * of a subpattern */
-	for (i = 1; i < bm->patlen; i++) {
-		for (j = 0; j < bm->patlen && bm->pattern[bm->patlen - 1 - j]
-				== bm->pattern[bm->patlen - 1 - i - j]; j++);
-		l[i] = j;
-	}  
-
 	bm->good_shift[0] = 1;
 	for (i = 1; i < bm->patlen; i++)
 		bm->good_shift[i] = bm->patlen;
-	for (i = bm->patlen - 1; i > 0; i--)
-		bm->good_shift[l[i]] = i;
-	ended = 0;
-	for (i = 0; i < bm->patlen; i++) {
-		if (l[i] == bm->patlen - 1 - i)
-			ended = i;
-		if (ended)
-			bm->good_shift[i] = ended;
+        for (i = bm->patlen-1, g = 1; i > 0; g++, i--) {
+		for (j = i-1; j >= 1-g ; j--)
+			if (subpattern(bm->pattern, i, j, g)) {
+				bm->good_shift[g] = bm->patlen-j-g;
+				break;
+			}
 	}
 }
 
 static struct ts_config *bm_init(const void *pattern, unsigned int len,
-				 int gfp_mask)
+				 gfp_t gfp_mask, int flags)
 {
 	struct ts_config *conf;
 	struct ts_bm *bm;
+	int i;
 	unsigned int prefix_tbl_len = len * sizeof(unsigned int);
 	size_t priv_size = sizeof(*bm) + len + prefix_tbl_len;
 
@@ -138,11 +155,16 @@ static struct ts_config *bm_init(const void *pattern, unsigned int len,
 	if (IS_ERR(conf))
 		return conf;
 
+	conf->flags = flags;
 	bm = ts_config_priv(conf);
 	bm->patlen = len;
 	bm->pattern = (u8 *) bm->good_shift + prefix_tbl_len;
-	compute_prefix_tbl(bm, pattern, len);
-	memcpy(bm->pattern, pattern, len);
+	if (flags & TS_IGNORECASE)
+		for (i = 0; i < len; i++)
+			bm->pattern[i] = toupper(((u8 *)pattern)[i]);
+	else
+		memcpy(bm->pattern, pattern, len);
+	compute_prefix_tbl(bm, flags);
 
 	return conf;
 }