Merge branch 'fix/CHT-824-limit-number-messages-loadhistory' into 'de…

…velop'

CHT-824. Limit to 256 number of messages that can be requested per block

Closes CHT-824

See merge request megachat/MEGAchat!1523

examples/megaclc/megaclc.cpp

@@ -102,7 +102,7 @@ std::mutex g_reviewPublicChatOutFileLogsMutex;
 std::unique_ptr<std::ofstream> g_reviewPublicChatOutFileLogs;
 class ReviewPublicChat_GetUserEmail_Listener;
 
-static const int MAX_NUMBER_MESSAGES = 300;
+static const int MAX_NUMBER_MESSAGES = 100; // chatd doesn't allow more than 256
 
 struct ConsoleLock
 {

src/chatdMsg.h

@@ -144,6 +144,8 @@ enum Opcode
       *    of OLDMSGs, followed by a HISTDONE. Note that count is always negative.
       * Send: <chatid> <count>
       *
+      * @note count is limited to 256
+      *
       * This command is sent at the following situations:
       *  1. After a JOIN command to load last messages, when no local history.
       *  2. When the app requests to load more old messages and there's no more history

src/megachatapi.h

@@ -44,6 +44,8 @@ typedef int MegaChatIndex;  // int32_t
 const MegaChatHandle MEGACHAT_INVALID_HANDLE = ~(MegaChatHandle)0;
 const MegaChatIndex MEGACHAT_INVALID_INDEX = 0x7fffffff;
 const MegaChatTimeStamp MEGACHAT_INVALID_TIMESTAMP = 0;
+const int MAX_MESSAGES_PER_BLOCK = 256;
+const int MIN_MESSAGES_PER_BLOCK = 1;
 
 class MegaChatApi;
 class MegaChatApiImpl;
@@ -4834,12 +4836,15 @@ class MegaChatApi
      * is local and there's no more history locally available, the number of messages could be
      * lower too (and the next call to MegaChatApi::loadMessages will fetch messages from server).
      *
+     * @note \c count has a maximun value of 256. If user requests more than 256 messages,
+     *  only 256 messages will returned if exits
+     *
      * When there are no more history available from the reported source of messages
      * (local / remote), or when the requested \c count has been already loaded,
      * the callback MegaChatRoomListener::onMessageLoaded will be called with a NULL message.
      *
      * @param chatid MegaChatHandle that identifies the chat room
-     * @param count The number of requested messages to load.
+     * @param count The number of requested messages to load (Range 1 - 256)
      *
      * @return Return the source of the messages that is going to be fetched. The possible values are:
      *   - MegaChatApi::SOURCE_ERROR = -1: history has to be fetched from server, but we are not logged in yet

src/megachatapi_impl.cpp

@@ -4799,6 +4799,13 @@ void MegaChatApiImpl::closeChatPreview(MegaChatHandle chatid)
 int MegaChatApiImpl::loadMessages(MegaChatHandle chatid, int count)
 {
     int ret = MegaChatApi::SOURCE_NONE;
+
+    if (count > MAX_MESSAGES_PER_BLOCK)
+    {
+        API_LOG_WARNING("count value is higher than chatd allows");
+    }
+
+    count = std::clamp(count, MIN_MESSAGES_PER_BLOCK, MAX_MESSAGES_PER_BLOCK);
     sdkMutex.lock();
 
     ChatRoom *chatroom = findChatRoom(chatid);