Make sure we match the same way when adding a mapping and looking up a mapping

Fixes https://github.com/libsdl-org/SDL/issues/6898

(cherry picked from commit 3db9112ef4cbb936b11f941f8a98c1704e37e140)

src/joystick/SDL_gamecontroller.c

@@ -752,9 +752,12 @@ static ControllerMapping_t *SDL_PrivateMatchControllerMappingForGUID(SDL_Joystic
 
         if (SDL_memcmp(&guid, &mapping_guid, sizeof(guid)) == 0) {
             Uint16 mapping_crc = 0;
-            const char *crc_string = SDL_strstr(mapping->mapping, SDL_CONTROLLER_CRC_FIELD);
-            if (crc_string) {
-                mapping_crc = (Uint16)SDL_strtol(crc_string + SDL_CONTROLLER_CRC_FIELD_SIZE, NULL, 16); 
+
+            if (match_crc) {
+                const char *crc_string = SDL_strstr(mapping->mapping, SDL_CONTROLLER_CRC_FIELD);
+                if (crc_string) {
+                    mapping_crc = (Uint16)SDL_strtol(crc_string + SDL_CONTROLLER_CRC_FIELD_SIZE, NULL, 16);
+                }
             }
             if (crc == mapping_crc) {
                 return mapping;
@@ -767,7 +770,7 @@ static ControllerMapping_t *SDL_PrivateMatchControllerMappingForGUID(SDL_Joystic
 /*
  * Helper function to scan the mappings database for a controller with the specified GUID
  */
-static ControllerMapping_t *SDL_PrivateGetControllerMappingForGUID(SDL_JoystickGUID guid)
+static ControllerMapping_t *SDL_PrivateGetControllerMappingForGUID(SDL_JoystickGUID guid, SDL_bool create_mapping)
 {
     ControllerMapping_t *mapping;
     Uint16 vendor, product, crc;
@@ -802,6 +805,10 @@ static ControllerMapping_t *SDL_PrivateGetControllerMappingForGUID(SDL_JoystickG
         }
     }
 
+    if (!create_mapping) {
+        return NULL;
+    }
+
 #if SDL_JOYSTICK_XINPUT
     if (SDL_IsJoystickXInput(guid)) {
         /* This is an XInput device */
@@ -1269,7 +1276,7 @@ SDL_PrivateAddMappingForGUID(SDL_JoystickGUID jGUID, const char *mappingString,
         }
     }
 
-    pControllerMapping = SDL_PrivateMatchControllerMappingForGUID(jGUID, SDL_TRUE, SDL_TRUE);
+    pControllerMapping = SDL_PrivateGetControllerMappingForGUID(jGUID, SDL_FALSE);
     if (pControllerMapping) {
         /* Only overwrite the mapping if the priority is the same or higher. */
         if (pControllerMapping->priority <= priority) {
@@ -1329,7 +1336,7 @@ static ControllerMapping_t *SDL_PrivateGetControllerMappingForNameAndGUID(const
 {
     ControllerMapping_t *mapping;
 
-    mapping = SDL_PrivateGetControllerMappingForGUID(guid);
+    mapping = SDL_PrivateGetControllerMappingForGUID(guid, SDL_TRUE);
 #ifdef __LINUX__
     if (!mapping && name) {
         if (SDL_strstr(name, "Xbox 360 Wireless Receiver")) {
@@ -1744,7 +1751,7 @@ SDL_GameControllerMappingForIndex(int mapping_index)
 char *
 SDL_GameControllerMappingForGUID(SDL_JoystickGUID guid)
 {
-    ControllerMapping_t *mapping = SDL_PrivateGetControllerMappingForGUID(guid);
+    ControllerMapping_t *mapping = SDL_PrivateGetControllerMappingForGUID(guid, SDL_TRUE);
     if (mapping) {
         return CreateMappingString(mapping, guid);
     } else {