Small test program triggering a self-deadlock in the memory allocator

when a signal handler that itself uses the allocator is invoked while
the thread originally was in the allocator.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@25449 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/tests/system/libroot/posix/Jamfile

@@ -24,6 +24,10 @@ SimpleTest setjmp_test2
 	: setjmp_test2.S
 ;
 
+SimpleTest signal_in_allocator_test
+	: signal_in_allocator_test.cpp
+;
+
 SimpleTest signal_test
 	: signal_test.cpp
 ;

src/tests/system/libroot/posix/signal_in_allocator_test.cpp

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2008, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <string.h>
+
+#include <OS.h>
+
+
+static int64 sHandledSignals = 0;
+
+
+static status_t
+signal_pusher(void* data)
+{
+	team_info teamInfo;
+	get_team_info(B_CURRENT_TEAM, &teamInfo);
+	thread_id mainThread = teamInfo.team;
+
+	while (true) {
+		send_signal(mainThread, SIGUSR1);
+		snooze(1000);
+	}
+
+	return B_OK;
+}
+
+
+static void
+signal_handler(int signal)
+{
+	free(malloc(10));
+	sHandledSignals++;
+}
+
+
+int
+main()
+{
+	const int testSeconds = 2;
+	printf("Trying to provoke allocator deadlock in signal handler.\n");
+	printf("If successful test will finish in %d seconds...\n", testSeconds);
+
+	// install signal handler
+	if (signal(SIGUSR1, signal_handler) == SIG_ERR) {
+		fprintf(stderr, "Error: Failed to install signal handler: %s\n",
+			strerror(errno));
+		exit(1);
+	}
+
+	// start signal thread
+	thread_id signalThread = spawn_thread(&signal_pusher, "signal pusher",
+		B_NORMAL_PRIORITY, NULL);
+	resume_thread(signalThread);
+
+	bigtime_t endTime = system_time() + 1000000 * (bigtime_t)testSeconds;
+	while (system_time() < endTime) {
+		const int allocationCount = 1000;
+		void* allocations[allocationCount];
+		for (int i = 0; i < allocationCount; i++)
+			allocations[i] = malloc(rand() % 50);
+		for (int i = 0; i < allocationCount; i++)
+			free(allocations[i]);
+	}
+
+	kill_thread(signalThread);
+	snooze(1000);
+
+	printf("test successful, handled %lld signals\n", sHandledSignals);
+
+	return 0;
+}