uuid: add id_read_format_try

Provide id_read_format() functionality without log_error
when ID is not valid one - it will just return 0.

Does not need to use log_suppress() then.

WHATS_NEW

@@ -1,5 +1,6 @@
 Version 2.02.137 -
 =====================================
+  Added internal id_read_format_try() function to check and read valid UUID.
   Use dm_get_status_mirror() instead of individual parsers.
   Add mem pool arg for check_transient_status() target function.
   Avoid misleading error with -m is omitted with lvconvert to raid types.

lib/uuid/uuid.c

@@ -132,7 +132,7 @@ static void _build_inverse(void)
 		_inverse_c[(int) *ptr] = (char) 0x1;
 }
 
-int id_valid(struct id *id)
+static int _id_valid(struct id *id, int e)
 {
 	int i;
 
@@ -140,6 +140,7 @@ int id_valid(struct id *id)
 
 	for (i = 0; i < ID_LEN; i++)
 		if (!_inverse_c[id->uuid[i]]) {
+			if (e)
 				log_error("UUID contains invalid character '%c'", id->uuid[i]);
 			return 0;
 		}
@@ -147,6 +148,12 @@ int id_valid(struct id *id)
 	return 1;
 }
 
+int id_valid(struct id *id)
+{
+	return _id_valid(id, 1);
+}
+
+
 int id_equal(const struct id *lhs, const struct id *rhs)
 {
 	return !memcmp(lhs->uuid, rhs->uuid, sizeof(lhs->uuid));
@@ -179,7 +186,7 @@ int id_write_format(const struct id *id, char *buffer, size_t size)
 	return 1;
 }
 
-int id_read_format(struct id *id, const char *buffer)
+static int _id_read_format(struct id *id, const char *buffer, int e)
 {
 	int out = 0;
 
@@ -192,6 +199,7 @@ int id_read_format(struct id *id, const char *buffer)
 		}
 
 		if (out >= ID_LEN) {
+			if (e)
 				log_error("Too many characters to be uuid.");
 			return 0;
 		}
@@ -200,12 +208,23 @@ int id_read_format(struct id *id, const char *buffer)
 	}
 
 	if (out != ID_LEN) {
+		if (e)
 			log_error("Couldn't read uuid: incorrect number of "
 				  "characters.");
 		return 0;
 	}
 
-	return id_valid(id);
+	return _id_valid(id, e);
+}
+
+int id_read_format(struct id *id, const char *buffer)
+{
+	return _id_read_format(id, buffer, 1);
+}
+
+int id_read_format_try(struct id *id, const char *buffer)
+{
+	return _id_read_format(id, buffer, 0);
 }
 
 char *id_format_and_copy(struct dm_pool *mem, const struct id *id)

lib/uuid/uuid.h

@@ -56,6 +56,10 @@ int id_write_format(const struct id *id, char *buffer, size_t size);
  * Reads a formatted uuid.
  */
 int id_read_format(struct id *id, const char *buffer);
+/*
+ * Tries to read a formatted uuid without logging error for invalid ID
+ */
+int id_read_format_try(struct id *id, const char *buffer);
 
 char *id_format_and_copy(struct dm_pool *mem, const struct id *id);