cmdinterface: Fix handling of extremely long lines

src/gamehistorylogger.cpp

@@ -367,7 +367,7 @@ void GameStoryLogger::logGameFrame()
 		// output frame
 		auto reportJSON = genFrameReport(gameFrames.back(), outputKey, outputNaming);
 		std::string reportJSONStr = std::string("__REPORT__") + reportJSON.dump(-1, ' ', false, nlohmann::ordered_json::error_handler_t::replace) + "__ENDREPORT__";
-		outputLine(reportJSONStr);
+		outputLine(std::move(reportJSONStr));
 	}
 }
 
@@ -402,7 +402,7 @@ void GameStoryLogger::logDebugModeChange(bool enabled)
 	if (outputModes.anyEnabled())
 	{
 		std::string reportJSONStr = std::string("__DEBUGMODE__") + ((enabled) ? "true" : "false") + "__ENDDEBUGMODE__";
-		outputLine(reportJSONStr);
+		outputLine(std::move(reportJSONStr));
 	}
 }
 
@@ -421,7 +421,7 @@ void GameStoryLogger::logGameOver()
 		bool hitTimeout = (game.gameTimeLimitMinutes > 0) ? (gameTime >= (game.gameTimeLimitMinutes * 60 * 1000)) : false;
 		auto reportJSON = genEndOfGameReport(outputKey, outputNaming, hitTimeout);
 		std::string reportJSONStr = std::string("__REPORTextended__") + reportJSON.dump(-1, ' ', false, nlohmann::ordered_json::error_handler_t::replace) + "__ENDREPORTextended__";
-		outputLine(reportJSONStr);
+		outputLine(std::move(reportJSONStr));
 	}
 
 	if (fileHandle)
@@ -643,30 +643,24 @@ inline void from_json(const nlohmann::json& j, GameStoryLogger::DebugModeEvent&
 	p.gameTime = j.at("gameTime").get<uint32_t>();
 }
 
-void GameStoryLogger::outputLine(const std::string &line)
+void GameStoryLogger::outputLine(std::string &&line)
 {
+	line.append("\n");
 	if (outputModes.cmdInterface)
 	{
-		wz_command_interface_output("%s\n", line.c_str());
+		wz_command_interface_output_str(line.c_str());
 	}
 	if (outputModes.logFile)
 	{
 		if (fileHandle)
 		{
 			if (WZ_PHYSFS_writeBytes(fileHandle, line.c_str(), line.size()) != line.size())
 			{
-				// Failed to write data to file
+				// Failed to write line to file
 				debug(LOG_ERROR, "Could not write to output file; PHYSFS error: %s", WZ_PHYSFS_getLastError());
 				PHYSFS_close(fileHandle);
 				fileHandle = nullptr;
 			}
-			if (WZ_PHYSFS_writeBytes(fileHandle, "\n", 1) != 1)
-			{
-				// Failed to write newline to file
-				debug(LOG_ERROR, "Could not write newline to output file; PHYSFS error: %s", WZ_PHYSFS_getLastError());
-				PHYSFS_close(fileHandle);
-				fileHandle = nullptr;
-			}
 			PHYSFS_flush(fileHandle);
 		}
 	}

src/gamehistorylogger.h

@@ -150,7 +150,7 @@ class GameStoryLogger
 	nlohmann::json genEndOfGameReport(OutputKey key, OutputNaming naming, bool timeout) const;
 	std::string getLogOutputFilename() const;
 
-	void outputLine(const std::string& line);
+	void outputLine(std::string&& line);
 
 private:
 	OutputModes outputModes;

src/stdinreader.cpp

@@ -1097,38 +1097,78 @@ bool wz_command_interface_enabled()
 	return wz_command_interface() != WZ_Command_Interface::None;
 }
 
-void wz_command_interface_output(const char *str, ...)
+void wz_command_interface_output_str(const char *str)
 {
 	if (wz_command_interface() == WZ_Command_Interface::None)
 	{
 		return;
 	}
-	va_list ap;
-	static char outputBuffer[maxReserveMessageBufferSize];
-	va_start(ap, str);
-	vssprintf(outputBuffer, str, ap);
-	va_end(ap);
 
-	size_t outputBufferLen = strlen(outputBuffer);
-	if (outputBufferLen == 0)
+	size_t bufferLen = strlen(str);
+	if (bufferLen == 0)
 	{
 		return;
 	}
 
 	if (wz_command_interface() == WZ_Command_Interface::StdIn_Interface)
 	{
-		fwrite(outputBuffer, sizeof(char), outputBufferLen, stderr);
+		fwrite(str, sizeof(char), bufferLen, stderr);
 		fflush(stderr);
 	}
 	else
 	{
-		latestWriteBuffer.insert(latestWriteBuffer.end(), outputBuffer, outputBuffer + outputBufferLen);
+		latestWriteBuffer.insert(latestWriteBuffer.end(), str, str + bufferLen);
 		cmdInterfaceOutputQueue->enqueue(std::move(latestWriteBuffer));
 		latestWriteBuffer = std::vector<char>();
 		latestWriteBuffer.reserve(maxReserveMessageBufferSize);
 	}
 }
 
+void wz_command_interface_output(const char *str, ...)
+{
+	if (wz_command_interface() == WZ_Command_Interface::None)
+	{
+		return;
+	}
+	va_list ap;
+	static char outputBuffer[maxReserveMessageBufferSize];
+	int ret = -1;
+	va_start(ap, str);
+	ret = vssprintf(outputBuffer, str, ap);
+	va_end(ap);
+	if (ret >= 0 && ret < maxReserveMessageBufferSize)
+	{
+		// string was completely written
+		wz_command_interface_output_str(outputBuffer);
+	}
+	else
+	{
+		// string was truncated - try again but use a heap-allocated string
+		if (ret < 0)
+		{
+			// some ancient implementations of vsnprintf return -1 instead of the needed buffer length...
+			errlog("WZCMD ERROR: Failed to output truncated string - check vsnprintf implementation");
+			return;
+		}
+		size_t neededBufferSize = static_cast<size_t>(ret);
+		char* tmpBuffer = (char *)malloc(neededBufferSize + 1);
+		va_start(ap, str);
+		ret = vsnprintf(tmpBuffer, neededBufferSize + 1, str, ap);
+		va_end(ap);
+		if (ret < 0 || ret >= neededBufferSize + 1)
+		{
+			errlog("WZCMD ERROR: Failed to output truncated string");
+			free(tmpBuffer);
+			return;
+		}
+		if (tmpBuffer)
+		{
+			wz_command_interface_output_str(tmpBuffer);
+			free(tmpBuffer);
+		}
+	}
+}
+
 void configSetCmdInterface(WZ_Command_Interface mode, std::string value)
 {
 	if (cmdInputThread || cmdOutputThread)

src/stdinreader.h

@@ -43,3 +43,5 @@ void wz_command_interface_output(const char *str, ...) WZ_DECL_FORMAT(__MINGW_PR
 #else
 void wz_command_interface_output(const char *str, ...) WZ_DECL_FORMAT(printf, 1, 2);
 #endif
+
+void wz_command_interface_output_str(const char *str);