Replace sizeof('\0') with sizeof("")

Because sizeof('\0') is actually sizeof(int) not sizeof(char).

cJSON.c

@@ -628,7 +628,7 @@ static const unsigned char *parse_string(cJSON * const item, const unsigned char
 
         /* This is at most how much we need for the output */
         allocation_length = (size_t) (input_end - input) - skipped_bytes;
-        output = (unsigned char*)hooks->allocate(allocation_length + sizeof('\0'));
+        output = (unsigned char*)hooks->allocate(allocation_length + sizeof(""));
         if (output == NULL)
         {
             goto fail; /* allocation failure */
@@ -1101,7 +1101,7 @@ static cJSON_bool print_value(const cJSON * const item, const size_t depth, cons
                 return false;
             }
 
-            raw_length = strlen(item->valuestring) + sizeof('\0');
+            raw_length = strlen(item->valuestring) + sizeof("");
             output = ensure(output_buffer, raw_length, hooks);
             if (output == NULL)
             {

fuzzing/afl.c

@@ -56,7 +56,7 @@ static char *read_file(const char *filename)
     }
 
     /* allocate content buffer */
-    content = (char*)malloc((size_t)length + sizeof('\0'));
+    content = (char*)malloc((size_t)length + sizeof(""));
     if (content == NULL)
     {
         goto cleanup;

tests/common.c

@@ -70,7 +70,7 @@ CJSON_PUBLIC(char*) read_file(const char *filename)
     }
 
     /* allocate content buffer */
-    content = (char*)malloc((size_t)length + sizeof('\0'));
+    content = (char*)malloc((size_t)length + sizeof(""));
     if (content == NULL)
     {
         goto cleanup;