MINOR: tools: add a generic binary hex string parser

We currently use such an hex parser in pat_parse_bin() to parse hex
string patterns. We'll need another generic one so let's move it to
standard.c and have pat_parse_bin() make use of it.

include/common/standard.h

@@ -508,6 +508,14 @@ static inline unsigned int popcount(unsigned int a)
 	return cnt;
 }
 
+/*
+ * Parse binary string written in hexadecimal (source) and store the decoded
+ * result into binstr and set binstrlen to the lengh of binstr. Memory for
+ * binstr is allocated by the function. In case of error, returns 0 with an
+ * error message in err.
+ */
+int parse_binary(const char *source, char **binstr, int *binstrlen, char **err);
+
 /* copies at most <n> characters from <src> and always terminates with '\0' */
 char *my_strndup(const char *src, int n);
 

src/pattern.c

@@ -440,39 +440,10 @@ int pat_parse_str(const char **text, struct pattern *pattern, struct sample_stor
 /* Parse a binary written in hexa. It is allocated. */
 int pat_parse_bin(const char **text, struct pattern *pattern, struct sample_storage *smp, int *opaque, char **err)
 {
-	int len;
-	const char *p = *text;
-	int i,j;
-
-	len  = strlen(p);
-	if (len%2) {
-		memprintf(err, "an even number of hex digit is expected");
-		return 0;
-	}
-
 	pattern->type = SMP_T_CBIN;
-	pattern->len = len >> 1;
-	pattern->ptr.str = malloc(pattern->len);
 	pattern->smp = smp;
-	if (!pattern->ptr.str) {
-		memprintf(err, "out of memory while loading string pattern");
-		return 0;
-	}
 
-	i = j = 0;
+	return parse_binary(*text, &pattern->ptr.str, &pattern->len, err);
-	while (j < pattern->len) {
-		if (!ishex(p[i++]))
-			goto bad_input;
-		if (!ishex(p[i++]))
-			goto bad_input;
-		pattern->ptr.str[j++] =  (hex2i(p[i-2]) << 4) + hex2i(p[i-1]);
-	}
-	return 1;
-
-bad_input:
-	memprintf(err, "an hex digit is expected (found '%c')", p[i-1]);
-	free(pattern->ptr.str);
-	return 0;
 }
 
 /* Parse and concatenate all further strings into one. */

src/standard.c

@@ -1356,6 +1356,48 @@ const char *parse_size_err(const char *text, unsigned *ret) {
 	return NULL;
 }
 
+/*
+ * Parse binary string written in hexadecimal (source) and store the decoded
+ * result into binstr and set binstrlen to the lengh of binstr. Memory for
+ * binstr is allocated by the function. In case of error, returns 0 with an
+ * error message in err.
+ */
+int parse_binary(const char *source, char **binstr, int *binstrlen, char **err)
+{
+	int len;
+	const char *p = source;
+	int i,j;
+
+	len = strlen(source);
+	if (len % 2) {
+		memprintf(err, "an even number of hex digit is expected");
+		return 0;
+	}
+
+	len = len >> 1;
+	*binstrlen = len;
+	*binstr = calloc(len, sizeof(char));
+	if (!*binstr) {
+		memprintf(err, "out of memory while loading string pattern");
+		return 0;
+	}
+
+	i = j = 0;
+	while (j < len) {
+		if (!ishex(p[i++]))
+			goto bad_input;
+		if (!ishex(p[i++]))
+			goto bad_input;
+		(*binstr)[j++] =  (hex2i(p[i-2]) << 4) + hex2i(p[i-1]);
+	}
+	return len;
+
+bad_input:
+	memprintf(err, "an hex digit is expected (found '%c')", p[i-1]);
+	free(binstr);
+	return 0;
+}
+
 /* copies at most <n> characters from <src> and always terminates with '\0' */
 char *my_strndup(const char *src, int n)
 {