fuzzing: test more decode functions

fuzzing/fuzz_decoder.c

@@ -6,7 +6,52 @@
 
 static void decode_binn(const unsigned char *buf, unsigned int len){
   binn item;
-  binn_load_ex(buf, len, &item);
+  binn value;
+  binn_iter iter;
+  char key[256], *pkey;
+  int id, pos;
+
+  // this will check the integrity of the buffer
+  if (binn_load_ex(buf, len, &item) == FALSE) return;
+
+  // buffers smaller than 4 bytes cause error
+  if (len < 4) return;
+
+  // try to read it as a list
+  binn_list_get_value(buf, 1, &value);
+  binn_list_get_value(buf, 2, &value);
+  binn_list_get_value(buf, 3, &value);
+
+  binn_list_foreach(buf, value) {
+    // do nothing
+  }
+
+  // try to read it as a map
+  binn_map_get_value(buf,    1, &value);
+  binn_map_get_value(buf,   10, &value);
+  binn_map_get_value(buf, 1024, &value);
+
+  for (pos=1; pos<=binn_count(buf); pos++) {
+    binn_map_get_pair(buf, pos, &id, &value);
+  }
+
+  binn_map_foreach(buf, id, value) {
+    binn_map_get_value(buf, id, &value);
+  }
+
+  // try to read it as an object
+  binn_object_get_value(buf, "name", &value);
+  binn_object_get_value(buf, "age",  &value);
+  binn_object_get_value(buf, "city", &value);
+
+  for (pos=1; pos<=binn_count(buf); pos++) {
+    binn_object_get_pair(buf, pos, key, &value);
+  }
+
+  binn_object_foreach(buf, key, value) {
+    binn_object_get_value(buf, key, &value);
+  }
+
 }
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {