From 7506fc9f00a64c2d69e60d7ef0189040d8a2fd36 Mon Sep 17 00:00:00 2001
From: Richard Ainger <raing3@gmail.com>
Date: Sun, 7 Aug 2022 12:48:00 +1000
Subject: [PATCH] Fixed infinite loop and crash which could occur when using
 "Import from cheat.db".

---
 UI/CwCheatScreen.cpp | 82 ++++++++++++++++++++++++--------------------
 UI/CwCheatScreen.h   |  1 +
 2 files changed, 45 insertions(+), 38 deletions(-)

diff --git a/UI/CwCheatScreen.cpp b/UI/CwCheatScreen.cpp
index aaf5b8e13a..567eab3f8d 100644
--- a/UI/CwCheatScreen.cpp
+++ b/UI/CwCheatScreen.cpp
@@ -201,7 +201,6 @@ UI::EventReturn CwCheatScreen::OnImportCheat(UI::EventParams &params) {
 	}
 	std::string line;
 	std::vector<std::string> title;
-	bool finished = false;
 	std::vector<std::string> newList;
 
 	Path cheatFile = GetSysDirectory(DIRECTORY_CHEATS) / "cheat.db";
@@ -215,43 +214,39 @@ UI::EventReturn CwCheatScreen::OnImportCheat(UI::EventParams &params) {
 	}
 
 	char linebuf[2048]{};
+	bool parseGameEntry = false;
+	bool parseCheatEntry = false;
+
 	while (in && !feof(in)) {
 		char *line = GetLineNoNewline(linebuf, sizeof(linebuf), in);
-		if (line && gameID == line) {
-			title.push_back(line);
-			line = GetLineNoNewline(linebuf, sizeof(linebuf), in);
-			if (line)
-				title.push_back(line);
-			do {
-				if (finished == false){
-					line = GetLineNoNewline(linebuf, sizeof(linebuf), in);
-				}
-				if (line && line[0] == '_' && line[1] == 'C') {
-					// Test if cheat already exists.
-					for (const auto &existing : fileInfo_) {
-						if (std::string(line).substr(4) == existing.name) {
-							finished = false;
-							goto loop;
-						}
-					}
 
-					newList.push_back(line);
-					line = GetLineNoNewline(linebuf, sizeof(linebuf), in);
-					do {
-						if (line)
-							newList.push_back(line);
-						line = GetLineNoNewline(linebuf, sizeof(linebuf), in);
-					} while ((line[0] == '_' && line[1] == 'L') || line[0] == '/' || line[0] == '#');
-					finished = true;
-				} else {
-					continue;
-				}
-			loop:;
-			} while (!feof(in) && ((line[0] == '_' && line[1] != 'S') || line[0] == '/' || line[0] == '#'));
-			finished = true;
+		if (!line) {
+			continue;
+		}
+
+		if (line[0] == '_' && line[1] == 'S') {
+			parseGameEntry = gameID == line;
+			parseCheatEntry = false;
+		} else if (parseGameEntry && line[0] == '_' && line[1] == 'C') {
+			// Test if cheat already exists.
+			parseCheatEntry = !HasCheatWithName(std::string(line).substr(4));
+		}
+
+		if (!parseGameEntry) {
+			if (newList.size() > 0) {
+				// Only parse the first matching game entry.
+				break;
+			} else {
+				// Haven't yet found a matching game entry, continue parsing.
+				continue;
+			}
+		}
+
+		if (line[0] == '_' && (line[1] == 'S' || line[1] == 'G') && title.size() < 2) {
+			title.push_back(line);
+		} else if (parseCheatEntry && (line[0] == '_' && (line[1] == 'C' || line[1] == 'L')) || line[0] == '/' || line[0] == '#') {
+			newList.push_back(line);
 		}
-		if (finished == true)
-			break;
 	}
 	fclose(in);
 
@@ -270,12 +265,13 @@ UI::EventReturn CwCheatScreen::OnImportCheat(UI::EventParams &params) {
 	if (!append)
 		return UI::EVENT_SKIPPED;
 
-	auto it = title.begin();
-	if (((title2[0] == '_' && title2[1] != 'S') || title2[0] == '/' || title2[0] == '#') && it != title.end() && (++it) != title.end()) {
-		fprintf(append, "%s\n%s", title[0].c_str(), title[1].c_str());
+	if (title2.size() == 0 || title2[0] != '_' || title2[1] != 'S') {
+		for (int i = (int)title.size(); i > 0; i--) {
+			newList.insert(newList.begin(), title[i - 1]);
+		}
 	}
 
-	NOTICE_LOG(COMMON, "Imported %u entries from %s.\n", (int)newList.size(), cheatFile.c_str());
+	NOTICE_LOG(COMMON, "Imported %u lines from %s.\n", (int)newList.size(), cheatFile.c_str());
 	if (newList.size() != 0) {
 		fputc('\n', append);
 	}
@@ -303,6 +299,16 @@ UI::EventReturn CwCheatScreen::OnCheckBox(int index) {
 	return UI::EVENT_DONE;
 }
 
+bool CwCheatScreen::HasCheatWithName(const std::string &name) {
+	for (const auto &existing : fileInfo_) {
+		if (name == existing.name) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
 bool CwCheatScreen::RebuildCheatFile(int index) {
 	if (!engine_)
 		return false;
diff --git a/UI/CwCheatScreen.h b/UI/CwCheatScreen.h
index 79f8386ce0..e2e167c771 100644
--- a/UI/CwCheatScreen.h
+++ b/UI/CwCheatScreen.h
@@ -48,6 +48,7 @@ private:
 	UI::EventReturn OnCheckBox(int index);
 
 	enum { INDEX_ALL = -1 };
+	bool HasCheatWithName(const std::string &name);
 	bool RebuildCheatFile(int index);
 
 	UI::ScrollView *rightScroll_ = nullptr;