test57: test that state isn't corrupted after a signal handler being executed.

2010-08-04 09:00:58 +00:00
parent b43f3b6bfc
commit 83fc90c8c3
4 changed files with 172 additions and 3 deletions
@@ -0,0 +1,102 @@
+
+/* This test tests whether registers are correctly restored after a
+ * signal handler is executed. The assembly file (test57loop.S) puts
+ * 'random' values in the registers, and the C code checks whether
+ * these values are the same, before and after the signal handler.
+ */
+
+#define _POSIX_SOURCE 1
+
+#include <stdio.h>
+#include <signal.h>
+#include <err.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#define SIGNAL SIGUSR1
+
+volatile int remaining_invocations = 2, handler_level = 0;
+
+void check_context_loop(void);
+
+#define REGS 8	/* how many registers pusha and popa save. */
+
+#define ESP 3	/* where is esp saved? */
+
+unsigned long newstate[REGS], origstate[REGS];
+
+void handler(int signal)
+{
+	int st;
+	sigset_t set, oset;
+	handler_level++;
+	remaining_invocations--;
+	if(remaining_invocations < 1)
+		return;
+	sigemptyset(&set);
+	sigaddset(&set, SIGNAL);
+	sigprocmask(SIG_UNBLOCK, &set,  &oset);
+	wait(&st);
+	handler_level--;
+}
+
+int main(int argc, char *argv[])
+{
+	pid_t child_pid;
+
+	printf("Test 57 ");
+
+	if(signal(SIGNAL, handler) == SIG_ERR)
+		err(1, "signal");
+
+	fflush(NULL);
+
+	if((child_pid=fork()) < 0)
+		err(1, "fork");
+
+	if(child_pid == 0) {
+		pid_t ppid = 0;
+
+		/* Keep signaling the parent until
+		 * it disappears.
+		 */
+		while((ppid = getppid()) > 1) {
+			if(kill(ppid, SIGNAL) < 0)
+				err(1, "kill");
+			sleep(1);
+		}
+
+		exit(0);
+	} else {
+		int i;
+		int err = 0;
+
+		check_context_loop();
+
+		/* correct 2nd esp for 'pusha' difference. */
+		newstate[ESP] += REGS*4;
+
+		for(i = 0; i < REGS; i++) {
+#if 0
+			printf("%d %08lx %08lx diff  ",
+				i, newstate[i], origstate[i]);
+#endif
+			if(newstate[i] != origstate[i]) {
+				fprintf(stderr, "reg %d changed; "
+					"found 0x%lx, expected 0x%lx\n",
+					i, newstate[i], origstate[i]);
+				err = 1;
+			}
+		}
+
+		if(!err) printf(" ok\n");
+
+		exit(err);
+	}
+
+	return 0;
+}
+