Add and use SavedReactionTags::calc_hash().

td/telegram/ReactionManager.cpp

@@ -12,6 +12,7 @@
 #include "td/telegram/Global.h"
 #include "td/telegram/logevent/LogEvent.h"
 #include "td/telegram/MessagesManager.h"
+#include "td/telegram/misc.h"
 #include "td/telegram/OptionManager.h"
 #include "td/telegram/ReactionManager.hpp"
 #include "td/telegram/StickerFormat.h"
@@ -307,9 +308,22 @@ void ReactionManager::SavedReactionTags::update_saved_messages_tags(const vector
   }
   if (is_changed) {
     std::sort(tags_.begin(), tags_.end());
+    hash_ = calc_hash();
   }
 }
 
+int64 ReactionManager::SavedReactionTags::calc_hash() const {
+  vector<uint64> numbers;
+  for (const auto &tag : tags_) {
+    numbers.push_back(tag.reaction_type_.get_hash());
+    if (!tag.title_.empty()) {
+      numbers.push_back(get_md5_string_hash(tag.title_));
+    }
+    numbers.push_back(tag.count_);
+  }
+  return get_vector_hash(numbers);
+}
+
 ReactionManager::ReactionManager(Td *td, ActorShared<> parent) : td_(td), parent_(std::move(parent)) {
 }
 
@@ -859,6 +873,9 @@ void ReactionManager::on_get_saved_messages_tags(
         tags_.tags_ = std::move(saved_reaction_tags);
         need_send_update = true;
       }
+      if (tags_.hash_ != tags_.calc_hash()) {
+        LOG(ERROR) << "Receive unexpected Saved Messages tag hash";
+      }
       tags_.is_inited_ = true;
       break;
     }

td/telegram/ReactionManager.h

@@ -163,6 +163,8 @@ class ReactionManager final : public Actor {
 
     void update_saved_messages_tags(const vector<ReactionType> &old_tags, const vector<ReactionType> &new_tags,
                                     bool &is_changed, bool &need_reload_title);
+
+    int64 calc_hash() const;
   };
 
   td_api::object_ptr<td_api::emojiReaction> get_emoji_reaction_object(const string &emoji) const;

td/telegram/ReactionType.cpp

@@ -134,6 +134,14 @@ td_api::object_ptr<td_api::updateDefaultReactionType> ReactionType::get_update_d
   return td_api::make_object<td_api::updateDefaultReactionType>(get_reaction_type_object());
 }
 
+uint64 ReactionType::get_hash() const {
+  if (is_custom_reaction()) {
+    return static_cast<uint64>(get_custom_emoji_id(reaction_));
+  } else {
+    return get_md5_string_hash(remove_emoji_selectors(reaction_));
+  }
+}
+
 bool ReactionType::is_custom_reaction() const {
   return reaction_[0] == '#';
 }

td/telegram/ReactionType.h

@@ -55,6 +55,8 @@ class ReactionType {
 
   td_api::object_ptr<td_api::updateDefaultReactionType> get_update_default_reaction_type() const;
 
+  uint64 get_hash() const;
+
   bool is_custom_reaction() const;
 
   bool is_active_reaction(const FlatHashMap<ReactionType, size_t, ReactionTypeHash> &active_reaction_pos) const;

td/telegram/misc.cpp

@@ -8,6 +8,7 @@
 
 #include "td/utils/algorithm.h"
 #include "td/utils/common.h"
+#include "td/utils/crypto.h"
 #include "td/utils/Hints.h"
 #include "td/utils/misc.h"
 #include "td/utils/Slice.h"
@@ -285,6 +286,16 @@ bool is_allowed_username(Slice username) {
   return true;
 }
 
+uint64 get_md5_string_hash(const string &str) {
+  unsigned char hash[16];
+  md5(str, {hash, sizeof(hash)});
+  uint64 result = 0;
+  for (int i = 0; i <= 7; i++) {
+    result += static_cast<uint64>(hash[i]) << (56 - 8 * i);
+  }
+  return result;
+}
+
 int64 get_vector_hash(const vector<uint64> &numbers) {
   uint64 acc = 0;
   for (auto number : numbers) {

td/telegram/misc.h

@@ -39,6 +39,9 @@ bool is_valid_username(Slice username);
 // checks whether a string can be set as a username
 bool is_allowed_username(Slice username);
 
+// calculates truncated MD5 hash of a string
+uint64 get_md5_string_hash(const string &str) TD_WARN_UNUSED_RESULT;
+
 // calculates hash of list of uint64
 int64 get_vector_hash(const vector<uint64> &numbers) TD_WARN_UNUSED_RESULT;