add writeJsonFile

Change-Id: I6269845fbd3b40d697bc7c77a457b380a5906bbc

1 files changed, 39 insertions, 2 deletions

diff --git a/src/hs-helper.cpp b/src/hs-helper.cpp
index 159668e..33ab721 100644
--- a/src/hs-helper.cpp
+++ b/src/hs-helper.cpp
@@ -283,12 +283,11 @@ std::string get_application_id(const afb_req_t request)
  *
  * #### Return
  * 0 : read success
- * 1 : read fail
+ * -1 : read fail
  *
  */
 int readJsonFile(const char* file, struct json_object **obj)
 {
-    *obj = nullptr;
     int ret = -1;
     FILE *fp = fopen(file, "rb");
     if(fp == nullptr) {
@@ -296,6 +295,7 @@ int readJsonFile(const char* file, struct json_object **obj)
         return ret;
     }
 
+    *obj = nullptr;
     const int buf_size = 128;
     char buf[buf_size];
     struct json_tokener *tokener = json_tokener_new();
@@ -321,3 +321,40 @@ int readJsonFile(const char* file, struct json_object **obj)
 	json_tokener_free(tokener);
 	return ret;
 }
+
+/**
+ * write to json file
+ *
+ * #### Parameters
+ * - file : output file name
+ * - obj : json_object
+ *
+ * #### Return
+ * 0 : read success
+ * -1 : read fail
+ *
+ */
+int writeJsonFile(const char* file,  struct json_object *obj)
+{
+    int ret = -1;
+    FILE *fp = fopen(file, "wb");
+    if(fp == nullptr) {
+        AFB_ERROR("open %s failed", file);
+        return ret;
+    }
+
+    const char *str = json_object_to_json_string(obj);
+    size_t len = sizeof(str);
+    size_t cnt = fwrite(str, len, 1, fp);
+    if(cnt == len) {
+        ret = 0;
+        fflush(fp);
+        fsync(fileno(fp));
+    }
+    else {
+        AFB_WARNING("write to %s failed.", file);
+    }
+
+    fclose(fp);
+    return ret;
+}
\ No newline at end of file