fuzzing: beautified and updated JSON target

Added 'nxt_conf_json_length' check for extra hit coverage.

Fixes: a93d878 ("fuzzing: add fuzzing targets")

fuzzing/nxt_json_fuzz.c

@@ -31,63 +31,78 @@ LLVMFuzzerInitialize(int *argc, char ***argv)
 int
 LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
-    nxt_mp_t               *mp;
-    nxt_str_t              input;
-    nxt_thread_t           *thr;
-    nxt_runtime_t          *rt;
-    nxt_conf_value_t       *conf;
-    nxt_conf_validation_t  vldt;
+    nxt_mp_t                *mp;
+    nxt_str_t               input;
+    nxt_thread_t            *thr;
+    nxt_runtime_t           *rt;
+    nxt_conf_value_t        *conf;
+    nxt_conf_validation_t   vldt;
+    nxt_conf_json_pretty_t  pretty;
 
     if (size < KMININPUTLENGTH || size > KMAXINPUTLENGTH) {
         return 0;
     }
 
+    input.start = (u_char *)data;
+    input.length = size;
+
+    nxt_memzero(&pretty, sizeof(nxt_conf_json_pretty_t));
+    nxt_memzero(&vldt, sizeof(nxt_conf_validation_t));
+
+
+    /*
+     * Create memory pool and validation pool.
+     * Initialize 'nxt_runtime_t'.
+     */
     thr = nxt_thread();
 
     mp = nxt_mp_create(1024, 128, 256, 32);
     if (mp == NULL) {
         return 0;
     }
 
+    vldt.pool = nxt_mp_create(1024, 128, 256, 32);
+    if (vldt.pool == NULL) {
+        nxt_mp_destroy(mp);
+        return 0;
+    }
+
     rt = nxt_mp_zget(mp, sizeof(nxt_runtime_t));
     if (rt == NULL) {
         goto failed;
     }
 
-    thr->runtime = rt;
-    rt->mem_pool = mp;
-
-    input.start = (u_char *)data;
-    input.length = size;
-
-    conf = nxt_conf_json_parse_str(mp, &input);
-    if (conf == NULL) {
+    rt->languages = nxt_array_create(mp, 1, sizeof(nxt_app_lang_module_t));
+    if (rt->languages == NULL) {
         goto failed;
     }
 
-    nxt_memzero(&vldt, sizeof(nxt_conf_validation_t));
-
-    vldt.pool = nxt_mp_create(1024, 128, 256, 32);
-    if (vldt.pool == NULL) {
-        goto failed;
-    }
+    rt->mem_pool = mp;
+    thr->runtime = rt;
 
-    vldt.conf = conf;
     vldt.conf_pool = mp;
     vldt.ver = NXT_VERNUM;
 
-    rt->languages = nxt_array_create(mp, 1, sizeof(nxt_app_lang_module_t));
-    if (rt->languages == NULL) {
+
+    /*
+     * Parse json and validate conf.
+     */
+    conf = nxt_conf_json_parse_str(mp, &input);
+    if (conf == NULL) {
         goto failed;
     }
 
+    nxt_conf_json_length(conf, NULL);
+    nxt_conf_json_length(conf, &pretty);
+
+    vldt.conf = conf;
     nxt_conf_validate(&vldt);
 
-    nxt_mp_destroy(vldt.pool);
 
 failed:
 
     nxt_mp_destroy(mp);
+    nxt_mp_destroy(vldt.pool);
 
     return 0;
 }