make TALER_MINT_parse_json_data more expressive

src/mint/taler-mint-httpd_parsing.c

@@ -462,76 +462,6 @@ GNUNET_MINT_parse_navigate_json (struct MHD_Connection *connection,
 }
 
 
-/**
- * Find a fixed-size field in the top-level of the JSON tree and store
- * it in @a data.
- *
- * Sends an error response if navigation is impossible (i.e.
- * the JSON object is invalid)
- *
- * @param connection the connection to send an error response to
- * @param root the JSON node to start the navigation at.
- * @param field name of the field to navigate to
- * @param data where to store the extracted data
- * @param data_size size of the @a data field
- * @param[IN|OUT] ret return value, function does nothing if @a ret is not #GNUNET_YES
- *                    on entry; will set @a ret to:
- *    #GNUNET_YES if navigation was successful
- *    #GNUNET_NO if json is malformed, error response was generated
- *    #GNUNET_SYSERR on internal error
- */
-static void
-parse_fixed_json_data (struct MHD_Connection *connection,
-                       const json_t *root,
-                       const char *field,
-                       void *data,
-                       size_t data_size,
-                       int *ret)
-{
-  if (GNUNET_YES != *ret)
-    return;
-  *ret = GNUNET_MINT_parse_navigate_json (connection,
-                                          root,
-                                          JNAV_FIELD, field,
-                                          JNAV_RET_DATA, data, data_size);
-}
-
-
-/**
- * Find a variable-size field in the top-level of the JSON tree and store
- * it in @a data.
- *
- * Sends an error response if navigation is impossible (i.e.
- * the JSON object is invalid)
- *
- * @param connection the connection to send an error response to
- * @param root the JSON node to start the navigation at.
- * @param field name of the field to navigate to
- * @param data where to store a pointer to memory allocated for the extracted data
- * @param[IN|OUT] ret return value, function does nothing if @a ret is not #GNUNET_YES
- *                    on entry; will set @a ret to:
- *    #GNUNET_YES if navigation was successful
- *    #GNUNET_NO if json is malformed, error response was generated
- *    #GNUNET_SYSERR on internal error
- */
-static void
-parse_variable_json_data (struct MHD_Connection *connection,
-                          const json_t *root,
-                          const char *field,
-                          void **data,
-                          size_t *data_size,
-                          int *ret)
-{
-  if (GNUNET_YES != *ret)
-    return;
-  *ret = GNUNET_MINT_parse_navigate_json (connection,
-                                          root,
-                                          JNAV_FIELD, field,
-                                          JNAV_RET_DATA_VAR, data, data_size);
-
-}
-
-
 /**
  * Parse JSON object into components based on the given field
  * specification.
@@ -558,23 +488,51 @@ TALER_MINT_parse_json_data (struct MHD_Connection *connection,
   ret = GNUNET_YES;
   for (i=0; NULL != spec[i].field_name; i++)
   {
-    if (0 == spec[i].destination_size_in)
+    switch (spec[i].command)
     {
-      ptr = NULL;
+    case JNAV_FIELD:
-      parse_variable_json_data (connection, root,
+      GNUNET_break (0);
-                                spec[i].field_name,
+      return GNUNET_SYSERR;
-                                &ptr,
+    case JNAV_INDEX:
-                                &spec[i].destination_size_out,
+      GNUNET_break (0);
-                                &ret);
+      return GNUNET_SYSERR;
-      spec[i].destination = ptr;
+    case JNAV_RET_DATA:
-    }
+      if (GNUNET_YES != ret)
-    else
+        break;
-    {
+      ret = GNUNET_MINT_parse_navigate_json (connection,
-      parse_fixed_json_data (connection, root,
+                                             root,
+                                             JNAV_FIELD,
                                              spec[i].field_name,
+                                             JNAV_RET_DATA,
                                              spec[i].destination,
-                             spec[i].destination_size_in,
+                                             spec[i].destination_size_in);
-                             &ret);
+      break;
+    case JNAV_RET_DATA_VAR:
+      if (GNUNET_YES != ret)
+        break;
+      ptr = NULL;
+      ret = GNUNET_MINT_parse_navigate_json (connection,
+                                             root,
+                                             JNAV_FIELD,
+                                             spec[i].field_name,
+                                             JNAV_RET_DATA_VAR,
+                                             &ptr,
+                                             &spec[i].destination_size_out);
+      spec[i].destination = ptr;
+      break;
+    case JNAV_RET_TYPED_JSON:
+      if (GNUNET_YES != ret)
+        break;
+      ptr = NULL;
+      ret = GNUNET_MINT_parse_navigate_json (connection,
+                                             root,
+                                             JNAV_FIELD,
+                                             spec[i].field_name,
+                                             JNAV_RET_TYPED_JSON,
+                                             spec[i].type,
+                                             &ptr);
+      spec[i].destination = ptr;
+      break;
     }
   }
   if (GNUNET_YES != ret)
@@ -595,13 +553,34 @@ TALER_MINT_release_parsed_data (struct GNUNET_MINT_ParseFieldSpec *spec)
   unsigned int i;
 
   for (i=0; NULL != spec[i].field_name; i++)
-    if ( (0 == spec[i].destination_size_in) &&
+  {
-         (0 != spec[i].destination_size_out) )
+    switch (spec[i].command)
+    {
+    case JNAV_FIELD:
+      GNUNET_break (0);
+      return;
+    case JNAV_INDEX:
+      GNUNET_break (0);
+      return;
+    case JNAV_RET_DATA:
+      break;
+    case JNAV_RET_DATA_VAR:
+      if (0 != spec[i].destination_size_out)
       {
         GNUNET_free (spec[i].destination);
         spec[i].destination = NULL;
         spec[i].destination_size_out = 0;
       }
+      break;
+    case JNAV_RET_TYPED_JSON:
+      if (NULL != spec[i].destination)
+      {
+        json_decref (spec[i].destination);
+        spec[i].destination = NULL;
+      }
+      break;
+    }
+  }
 }
 
 
@@ -774,7 +753,6 @@ TALER_MINT_mhd_request_var_arg_data (struct MHD_Connection *connection,
   *out_data = out;
   *out_size = olen;
   return GNUNET_OK;
-
 }
 
 

src/mint/taler-mint-httpd_parsing.h

@@ -162,6 +162,22 @@ struct GNUNET_MINT_ParseFieldSpec
    * variable-size allocations).
    */
   size_t destination_size_out;
+
+  /**
+   * Navigation command to use to extract the value.  Note that
+   * #JNAV_RET_DATA or #JNAV_RET_DATA_VAR must be used for @e
+   * destination_size_in and @e destination_size_out to have a
+   * meaning.  #JNAV_FIELD and #JNAV_INDEX must not be used here!
+   */
+  enum TALER_MINT_JsonNavigationCommand command;
+
+  /**
+   * JSON type to use, only meaningful in connection with a @e command
+   * value of #JNAV_RET_TYPED_JSON.  Typical values are
+   * #JSON_ARRAY and #JSON_OBJECT.
+   */
+  int type;
+
 };
 
 
@@ -201,19 +217,34 @@ TALER_MINT_release_parsed_data (struct GNUNET_MINT_ParseFieldSpec *spec);
  * @param field name of the field
  * @param value where to store the value
  */
-#define TALER_MINT_PARSE_FIXED(field,value) { field, value, sizeof (*value), 0 }
+#define TALER_MINT_PARSE_FIXED(field,value) { field, value, sizeof (*value), 0, JNAV_RET_DATA, 0 }
 
 /**
  * Generate line in parser specification for variable-size value.
  *
  * @param field name of the field
  */
-#define TALER_MINT_PARSE_VARIABLE(field) { field, NULL, 0, 0 }
+#define TALER_MINT_PARSE_VARIABLE(field) { field, NULL, 0, 0, JNAV_RET_DATA_VAR, 0 }
+
+/**
+ * Generate line in parser specification for JSON array value.
+ *
+ * @param field name of the field
+ */
+#define TALER_MINT_PARSE_ARRAY(field) { field, NULL, 0, 0, JNAV_RET_TYPED_JSON, JSON_ARRAY }
+
+/**
+ * Generate line in parser specification for JSON object value.
+ *
+ * @param field name of the field
+ */
+#define TALER_MINT_PARSE_OBJECT(field) { field, NULL, 0, 0, JNAV_RET_TYPED_JSON, JSON_OBJECT }
+
 
 /**
  * Generate line in parser specification indicating the end of the spec.
  */
-#define TALER_MINT_PARSE_END { NULL, NULL, 0, 0 }
+#define TALER_MINT_PARSE_END { NULL, NULL, 0, 0, JNAV_FIELD, 0 }
 
 
 /**

src/mint/taler-mint-httpd_refresh.c

@@ -275,29 +275,57 @@ TALER_MINT_handler_refresh_melt (struct RequestHandler *rh,
   if ( (GNUNET_NO == res) || (NULL == root) )
     return MHD_YES;
 
-  /* session_pub field must always be present */
+  res = GNUNET_MINT_parse_navigate_json (connection,
-  res = GNUNET_MINT_parse_navigate_json (connection, root,
+                                         root,
-                                  JNAV_FIELD, "session_pub",
+                                         JNAV_FIELD,
+                                         "session_pub",
                                          JNAV_RET_DATA,
                                          &refresh_session_pub,
                                          sizeof (struct GNUNET_CRYPTO_EddsaPublicKey));
-  if (GNUNET_OK != res)
+  if (GNUNET_SYSERR == res)
-  {
-    // FIXME: return 'internal error'?
-    GNUNET_break (0);
     return MHD_NO;
-  }
   if (GNUNET_NO == res)
     return MHD_YES;
-
+  res = GNUNET_MINT_parse_navigate_json (connection,
-  res = GNUNET_MINT_parse_navigate_json (connection, root,
+                                         root,
-                                         JNAV_FIELD, "new_denoms",
+                                         JNAV_FIELD,
+                                         "new_denoms",
                                          JNAV_RET_TYPED_JSON,
                                          JSON_ARRAY,
                                          &new_denoms);
+  if (GNUNET_SYSERR == res)
+    return MHD_NO;
+  if (GNUNET_NO == res)
+    return MHD_YES;
+
+  res = GNUNET_MINT_parse_navigate_json (connection,
+                                         root,
+                                         JNAV_FIELD,
+                                         "melt_coins",
+                                         JNAV_RET_TYPED_JSON,
+                                         JSON_ARRAY,
+                                         &melt_coins);
   if (GNUNET_OK != res)
+    {
+      // FIXME: leaks!
       return res;
+    }
+
+  melt_sig_json = json_object_get (root,
+                                   "melt_signature");
+  if (NULL == melt_sig_json)
+  {
+    return TALER_MINT_reply_json_pack (connection,
+                                       MHD_HTTP_BAD_REQUEST,
+                                       "{s:s}",
+                                       "error",
+                                       "melt_signature missing");
+  }
+
+
+
   num_new_denoms = json_array_size (new_denoms);
+
   denom_pubs = GNUNET_malloc (num_new_denoms *
                               sizeof (struct GNUNET_CRYPTO_rsa_PublicKey *));
 
@@ -326,27 +354,8 @@ TALER_MINT_handler_refresh_melt (struct RequestHandler *rh,
     }
   }
 
-  res = GNUNET_MINT_parse_navigate_json (connection, root,
-                                         JNAV_FIELD, "melt_coins",
-                                         JNAV_RET_TYPED_JSON,
-                                         JSON_ARRAY,
-                                         &melt_coins);
-  if (GNUNET_OK != res)
-    {
-      // FIXME: leaks!
-      return res;
-    }
 
-  melt_sig_json = json_object_get (root,
+
-                                   "melt_signature");
-  if (NULL == melt_sig_json)
-  {
-    return TALER_MINT_reply_json_pack (connection,
-                                       MHD_HTTP_BAD_REQUEST,
-                                       "{s:s}",
-                                       "error",
-                                       "melt_signature missing");
-  }
 
   coin_count = json_array_size (melt_coins);
   coin_public_infos = GNUNET_malloc (coin_count *