Codechange: Use std::deque for chat history instead of fixed array

1 files changed, 16 insertions, 44 deletions

diff --git a/src/network/network_chat_gui.cpp b/src/network/network_chat_gui.cpp
index 80a0b7869..a1157e261 100644
--- a/src/network/network_chat_gui.cpp
+++ b/src/network/network_chat_gui.cpp
@@ -8,6 +8,7 @@
 /** @file network_chat_gui.cpp GUI for handling chat messages. */
 
 #include <stdarg.h> /* va_list */
+#include <deque>
 
 #include "../stdafx.h"
 #include "../strings_func.h"
@@ -44,7 +45,7 @@ struct ChatMessage {
 };
 
 /* used for chat window */
-static ChatMessage *_chatmsg_list = nullptr; ///< The actual chat message list.
+static std::deque<ChatMessage> _chatmsg_list; ///< The actual chat message list.
 static bool _chatmessage_dirty = false;   ///< Does the chat message need repainting?
 static bool _chatmessage_visible = false; ///< Is a chat message visible.
 static bool _chat_tab_completion_active;  ///< Whether tab completion is active.
@@ -58,20 +59,6 @@ static PointDimension _chatmsg_box;
 static uint8 *_chatmessage_backup = nullptr; ///< Backup in case text is moved.
 
 /**
- * Count the chat messages.
- * @return The number of chat messages.
- */
-static inline uint GetChatMessageCount()
-{
-	uint i = 0;
-	for (; i < MAX_CHAT_MESSAGES; i++) {
-		if (_chatmsg_list[i].message[0] == '\0') break;
-	}
-
-	return i;
-}
-
-/**
  * Add a text message to the 'chat window' to be shown
  * @param colour The colour this message is to be shown in
  * @param duration The duration of the chat message in seconds
@@ -88,13 +75,11 @@ void CDECL NetworkAddChatMessage(TextColour colour, uint duration, const char *m
 
 	Utf8TrimString(buf, DRAW_STRING_BUFFER);
 
-	uint msg_count = GetChatMessageCount();
-	if (MAX_CHAT_MESSAGES == msg_count) {
-		memmove(&_chatmsg_list[0], &_chatmsg_list[1], sizeof(_chatmsg_list[0]) * (msg_count - 1));
-		msg_count = MAX_CHAT_MESSAGES - 1;
+	if (_chatmsg_list.size() == MAX_CHAT_MESSAGES) {
+		_chatmsg_list.pop_back();
 	}
 
-	ChatMessage *cmsg = &_chatmsg_list[msg_count++];
+	ChatMessage *cmsg = &_chatmsg_list.emplace_front();
 	strecpy(cmsg->message, buf, lastof(cmsg->message));
 	cmsg->colour = (colour & TC_IS_PALETTE_COLOUR) ? colour : TC_WHITE;
 	cmsg->remove_time = std::chrono::steady_clock::now() + std::chrono::seconds(duration);
@@ -115,15 +100,11 @@ void NetworkInitChatMessage()
 {
 	MAX_CHAT_MESSAGES    = _settings_client.gui.network_chat_box_height;
 
-	_chatmsg_list        = ReallocT(_chatmsg_list, _settings_client.gui.network_chat_box_height);
+	_chatmsg_list.clear();
 	_chatmsg_box.x       = 10;
 	_chatmsg_box.width   = _settings_client.gui.network_chat_box_width_pct * _screen.width / 100;
 	NetworkReInitChatBoxSize();
 	_chatmessage_visible = false;
-
-	for (uint i = 0; i < MAX_CHAT_MESSAGES; i++) {
-		_chatmsg_list[i].message[0] = '\0';
-	}
 }
 
 /** Hide the chatbox */
@@ -175,21 +156,13 @@ void NetworkUndrawChatMessage()
 /** Check if a message is expired. */
 void NetworkChatMessageLoop()
 {
-	for (uint i = 0; i < MAX_CHAT_MESSAGES; i++) {
-		ChatMessage *cmsg = &_chatmsg_list[i];
-		if (cmsg->message[0] == '\0') continue;
-
+	for (auto it = _chatmsg_list.begin(); it != _chatmsg_list.end();) {
 		/* Message has expired, remove from the list */
-		if (std::chrono::steady_clock::now() > cmsg->remove_time) {
-			/* Move the remaining messages over the current message */
-			if (i != MAX_CHAT_MESSAGES - 1) memmove(cmsg, cmsg + 1, sizeof(*cmsg) * (MAX_CHAT_MESSAGES - i - 1));
-
-			/* Mark the last item as empty */
-			_chatmsg_list[MAX_CHAT_MESSAGES - 1].message[0] = '\0';
+		if (std::chrono::steady_clock::now() > it->remove_time) {
+			it = _chatmsg_list.erase(it);
 			_chatmessage_dirty = true;
-
-			/* Go one item back, because we moved the array 1 to the left */
-			i--;
+		} else {
+			it++;
 		}
 	}
 }
@@ -206,8 +179,7 @@ void NetworkDrawChatMessage()
 	if (_iconsole_mode == ICONSOLE_FULL) return;
 
 	/* Check if we have anything to draw at all */
-	uint count = GetChatMessageCount();
-	if (count == 0) return;
+	if (_chatmsg_list.size() == 0) return;
 
 	int x      = _chatmsg_box.x;
 	int y      = _screen.height - _chatmsg_box.y - _chatmsg_box.height;
@@ -230,8 +202,8 @@ void NetworkDrawChatMessage()
 	_cur_dpi = &_screen; // switch to _screen painting
 
 	int string_height = 0;
-	for (uint i = 0; i < count; i++) {
-		SetDParamStr(0, _chatmsg_list[i].message);
+	for (auto &cmsg : _chatmsg_list) {
+		SetDParamStr(0, cmsg.message);
 		string_height += GetStringLineCount(STR_JUST_RAW_STRING, width - 1) * FONT_HEIGHT_NORMAL + NETWORK_CHAT_LINE_SPACING;
 	}
 
@@ -247,8 +219,8 @@ void NetworkDrawChatMessage()
 	/* Paint the chat messages starting with the lowest at the bottom */
 	int ypos = bottom - 2;
 
-	for (int i = count - 1; i >= 0; i--) {
-		ypos = DrawStringMultiLine(_chatmsg_box.x + 3, _chatmsg_box.x + _chatmsg_box.width - 1, top, ypos, _chatmsg_list[i].message, _chatmsg_list[i].colour, SA_LEFT | SA_BOTTOM | SA_FORCE) - NETWORK_CHAT_LINE_SPACING;
+	for (auto &cmsg : _chatmsg_list) {
+		ypos = DrawStringMultiLine(_chatmsg_box.x + 3, _chatmsg_box.x + _chatmsg_box.width - 1, top, ypos, cmsg.message, cmsg.colour, SA_LEFT | SA_BOTTOM | SA_FORCE) - NETWORK_CHAT_LINE_SPACING;
 		if (ypos < top) break;
 	}