MINOR: standard: Add a function to parse uints (dotted notation).

This function is useful to parse strings made of unsigned integers
and to allocate a C array of unsigned integers from there.
For instance this function allocates this array { 1, 2, 3, 4, } from
this string: "1.2.3.4".

include/common/standard.h

@@ -1367,6 +1367,8 @@ static inline void *my_realloc2(void *ptr, size_t size)
 	return ret;
 }
 
+int parse_dotted_uints(const char *s, unsigned int **nums, size_t *sz);
+
 /* HAP_STRING() makes a string from a literal while HAP_XSTRING() first
  * evaluates the argument and is suited to pass macros.
  *

src/standard.c

@@ -4058,6 +4058,50 @@ void debug_hexdump(FILE *out, const char *pfx, const char *buf,
 	}
 }
 
+/*
+ * Allocate an array of unsigned int with <nums> as address from <str> string
+ * made of integer sepereated by dot characters.
+ *
+ * First, initializes the value with <sz> as address to 0 and initializes the
+ * array with <nums> as address to NULL. Then allocates the array with <nums> as
+ * address updating <sz> pointed value to the size of this array.
+ *
+ * Returns 1 if succeeded, 0 if not.
+ */
+int parse_dotted_uints(const char *str, unsigned int **nums, size_t *sz)
+{
+	unsigned int *n;
+	const char *s, *end;
+
+	s = str;
+	*sz = 0;
+	end = str + strlen(str);
+	*nums = n = NULL;
+
+	while (1) {
+		unsigned int r;
+
+		if (s >= end)
+			break;
+
+		r = read_uint(&s, end);
+		/* Expected characters after having read an uint: '\0' or '.',
+		 * if '.', must not be terminal.
+		 */
+		if (*s != '\0'&& (*s++ != '.' || s == end))
+			return 0;
+
+		n = my_realloc2(n, *sz + 1);
+		if (!n)
+			return 0;
+
+		n[(*sz)++] = r;
+	}
+	*nums = n;
+
+	return 1;
+}
+
 /* do nothing, just a placeholder for debugging calls, the real one is in trace.c */
 __attribute__((weak,format(printf, 1, 2)))
 void trace(char *msg, ...)