Clang warnings (#7090)

* clang_warnings: Fix unecessary comparison

Netdata was verifying whether a pointer that will never be NULL could be NULL.
This commit removes this

* clang_warnings: Fix unecessary comparison

Netdata was doing another unecessary comparison in other file

* clang_warnings: Unecessary parenthesis

This commit removes the excess of parenthesis in a file

* clang_warnings: Remove unecessary initialization

Remove from json file a initial set that is overwritten few lines late

* clang_warnings: Comments

Fix comments on top of the function

* clang_warnings: Missing Cast

Volatile variable generates warnings with Clang sometimes, so it
was necessary to cast variables

* clang_warnings: Return from previous

Considering the possible problems given by the solution,
I am returning for the previous stage

2 files changed, 4 insertions, 9 deletions

diff --git a/libnetdata/health/health.c b/libnetdata/health/health.c
index a70f284b1f..e03538db3f 100644
--- a/libnetdata/health/health.c
+++ b/libnetdata/health/health.c
@@ -112,7 +112,7 @@ int health_silencers_json_read_callback(JSON_ENTRY *e)
         case JSON_OBJECT:
 #ifndef ENABLE_JSONC
             e->callback_function = health_silencers_json_read_callback;
-            if(e->name && strcmp(e->name,"")) {
+            if(strcmp(e->name,"")) {
                 // init silencer
                 debug(D_HEALTH, "JSON: Got object with a name, initializing new silencer for %s",e->name);
 #endif
diff --git a/libnetdata/json/json.c b/libnetdata/json/json.c
index 7c5adca3db..3ccc561c6f 100644
--- a/libnetdata/json/json.c
+++ b/libnetdata/json/json.c
@@ -284,18 +284,13 @@ size_t json_walk_primitive(char *js, jsmntok_t *t, size_t start, JSON_ENTRY *e)
  * @param t the tokens
  * @param nest the length of structure t
  * @param start the first position
- * @param e the output structure.
+ * @param e the structure with values and callback to be used inside the function.
  *
  * @return It returns the array length
  */
 size_t json_walk_array(char *js, jsmntok_t *t, size_t nest, size_t start, JSON_ENTRY *e)
 {
-    JSON_ENTRY ne = {
-            .name = "",
-            .fullname = "",
-            .callback_data = NULL,
-            .callback_function = NULL
-    };
+    JSON_ENTRY ne;
 
     char old = js[t[start].end];
     js[t[start].end] = '\0';
@@ -315,7 +310,7 @@ size_t json_walk_array(char *js, jsmntok_t *t, size_t nest, size_t start, JSON_E
     start++;
     for(i = 0; i < size ; i++) {
         ne.pos = i;
-        if (!e->name || !e->fullname || strlen(e->name) > JSON_NAME_LEN  - 24 || strlen(e->fullname) > JSON_FULLNAME_LEN -24) {
+        if (strlen(e->name) > JSON_NAME_LEN  - 24 || strlen(e->fullname) > JSON_FULLNAME_LEN -24) {
             info("JSON: JSON walk_array ignoring element with name:%s fullname:%s",e->name, e->fullname);
             continue;
         }