fix: Watcher on MacOS (#254)

* fix: Watcher on MacOS

* fix: Kill time limit for watcher

Author: aberter0x3f

src/core/judgingthread.cpp

@@ -954,7 +954,7 @@ void JudgingThread::runProgram() {
 	}
 
 	argumentsList << "_tmperr";
-	argumentsList << QString("%1").arg(timeLimit + extraTime);
+	argumentsList << QString("%1").arg(timeLimit);
 	argumentsList << QString("%1").arg(memoryLimit);
 	argumentsList << QString("%1").arg(rawTimeLimit);
 	argumentsList << QString("%1").arg(rawMemoryLimit);
@@ -1007,7 +1007,7 @@ void JudgingThread::runProgram() {
 	}
 
 	argumentsList << "_tmperr";
-	argumentsList << QString("%1").arg(timeLimit + extraTime);
+	argumentsList << QString("%1").arg(timeLimit);
 	argumentsList << QString("%1").arg(memoryLimit);
 	argumentsList << QString("%1").arg(rawTimeLimit);
 	argumentsList << QString("%1").arg(rawMemoryLimit);
@@ -1044,7 +1044,10 @@ void JudgingThread::runProgram() {
 	QElapsedTimer timer;
 	timer.start();
 
-	while (timer.elapsed() <= timeLimit + extraTime) {
+	// Using rlimit to limit CPU time can only be accurate to seconds,
+	// so here it is rounded up to an integer second.
+	long long killTimeLimit = (timeLimit + 999) / 1000 * 1000 + extraTime;
+	while (timer.elapsed() <= killTimeLimit) {
 		if (runner->state() != QProcess::Running) {
 			isProgramFinishedInExtraTimeLimit = true;
 			break;

unix/watcher_unix.cpp

@@ -144,29 +144,20 @@ auto main(int argc, char *argv[]) -> int {
 			return RS_RE;
 		}
 	} else {
-		if (! stdinRedirect.empty()) {
-			if (freopen(stdinRedirect.c_str(), "r", stdin) == NULL) {
-				perror("freopen stdin");
-				exit(RS_FAIL);
-			}
-		} else {
-			fclose(stdin);
+		std::string finalStdinRedirect = stdinRedirect.empty() ? "/dev/null" : stdinRedirect;
+		if (freopen(finalStdinRedirect.c_str(), "r", stdin) == NULL) {
+			perror("freopen stdin");
+			exit(RS_FAIL);
 		}
-		if (! stdoutRedirect.empty()) {
-			if (freopen(stdoutRedirect.c_str(), "w", stdout) == NULL) {
-				perror("freopen stdout");
-				exit(RS_FAIL);
-			}
-		} else {
-			fclose(stdout);
+		std::string finalStdoutRedirect = stdoutRedirect.empty() ? "/dev/null" : stdoutRedirect;
+		if (freopen(finalStdoutRedirect.c_str(), "w", stdout) == NULL) {
+			perror("freopen stdout");
+			exit(RS_FAIL);
 		}
-		if (! stderrRedirect.empty()) {
-			if (freopen(stderrRedirect.c_str(), "w", stderr) == NULL) {
-				perror("freopen stderr");
-				exit(RS_FAIL);
-			}
-		} else {
-			fclose(stderr);
+		std::string finalStderrRedirect = stderrRedirect.empty() ? "/dev/null" : stderrRedirect;
+		if (freopen(finalStderrRedirect.c_str(), "w", stderr) == NULL) {
+			perror("freopen stderr");
+			exit(RS_FAIL);
 		}
 
 		rlimit memlim{}, stalim{}, timlim{};