match KEY="A|B" without temporary string copy

2 files changed, 43 insertions, 13 deletions

diff --git a/test/udev-test.pl b/test/udev-test.pl
index 9725aff5ba..f630b74a9d 100755
--- a/test/udev-test.pl
+++ b/test/udev-test.pl
@@ -1451,6 +1451,31 @@ KERNEL=="dontknow*|ttyACM*|nothing*", NAME="right"
 EOF
 	},
 	{
+		desc		=> "test multi matches 3",
+		subsys		=> "tty",
+		devpath		=> "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+		exp_name	=> "right",
+		rules		=> <<EOF
+KERNEL=="dontknow|nothing", NAME="nomatch"
+KERNEL=="dontknow|ttyACM0a|nothing|attyACM0", NAME="wrong1"
+KERNEL=="X|attyACM0|dontknow|ttyACM0a|nothing|attyACM0", NAME="wrong2"
+KERNEL=="dontknow|ttyACM0|nothing", NAME="right"
+EOF
+	},
+	{
+		desc		=> "test multi matches 4",
+		subsys		=> "tty",
+		devpath		=> "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+		exp_name	=> "right",
+		rules		=> <<EOF
+KERNEL=="dontknow|nothing", NAME="nomatch"
+KERNEL=="dontknow|ttyACM0a|nothing|attyACM0", NAME="wrong1"
+KERNEL=="X|attyACM0|dontknow|ttyACM0a|nothing|attyACM0", NAME="wrong2"
+KERNEL=="all|dontknow|ttyACM0", NAME="right"
+KERNEL=="ttyACM0a|nothing", NAME="wrong3"
+EOF
+	},
+	{
 		desc		=> "IMPORT parent test sequence 1/2 (keep)",
 		subsys		=> "block",
 		devpath		=> "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
diff --git a/udev/udev-rules.c b/udev/udev-rules.c
index 0643811d7a..8c0e1d961b 100644
--- a/udev/udev-rules.c
+++ b/udev/udev-rules.c
@@ -1726,21 +1726,26 @@ static int match_key(struct udev_rules *rules, struct token *token, const char *
 		break;
 	case GL_SPLIT:
 		{
-			char value[UTIL_PATH_SIZE];
+			const char *split;
+			size_t len;
 
-			util_strlcpy(value, &rules->buf[token->key.value_off], sizeof(value));
-			key_value = value;
-			while (key_value != NULL) {
-				pos = strchr(key_value, '|');
-				if (pos != NULL) {
-					pos[0] = '\0';
-					pos = &pos[1];
-				}
-				dbg(rules->udev, "match %s '%s' <-> '%s'\n", token_str[token->type], key_value, val);
-				match = (strcmp(key_value, val) == 0);
-				if (match)
+			split = &rules->buf[token->key.value_off];
+			len = strlen(val);
+			while (1) {
+				const char *next;
+
+				next = strchr(split, '|');
+				if (next != NULL) {
+					size_t matchlen = (size_t)(next - split);
+
+					match = (matchlen == len && strncmp(split, val, matchlen) == 0);
+					if (match)
+						break;
+				} else {
+					match = (strcmp(split, val) == 0);
 					break;
-				key_value = pos;
+				}
+				split = &next[1];
 			}
 			break;
 		}