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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Test installing a signal handler before the Go code starts.
// This is a lot like misc/cgo/testcshared/main4.c.
#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <sched.h>
#include <time.h>
#include <errno.h>
#include "libgo2.h"
static void die(const char* msg) {
perror(msg);
exit(EXIT_FAILURE);
}
static volatile sig_atomic_t sigioSeen;
static volatile sig_atomic_t sigpipeSeen;
// Use up some stack space.
static void recur(int i, char *p) {
char a[1024];
*p = '\0';
if (i > 0) {
recur(i - 1, a);
}
}
static void pipeHandler(int signo, siginfo_t* info, void* ctxt) {
sigpipeSeen = 1;
}
// Signal handler that uses up more stack space than a goroutine will have.
static void ioHandler(int signo, siginfo_t* info, void* ctxt) {
char a[1024];
recur(4, a);
sigioSeen = 1;
}
static jmp_buf jmp;
static char* nullPointer;
// An arbitrary function which requires proper stack alignment; see
// http://golang.org/issue/17641.
static void callWithVarargs(void* dummy, ...) {
va_list args;
va_start(args, dummy);
va_end(args);
}
// Signal handler for SIGSEGV on a C thread.
static void segvHandler(int signo, siginfo_t* info, void* ctxt) {
sigset_t mask;
int i;
// Call an arbitrary function that requires the stack to be properly aligned.
callWithVarargs("dummy arg", 3.1415);
if (sigemptyset(&mask) < 0) {
die("sigemptyset");
}
if (sigaddset(&mask, SIGSEGV) < 0) {
die("sigaddset");
}
i = sigprocmask(SIG_UNBLOCK, &mask, NULL);
if (i != 0) {
fprintf(stderr, "sigprocmask: %s\n", strerror(i));
exit(EXIT_FAILURE);
}
// Don't try this at home.
longjmp(jmp, signo);
// We should never get here.
abort();
}
// Set up the signal handlers in a high priority constructor,
// so that they are installed before the Go code starts.
static void init(void) __attribute__ ((constructor (200)));
static void init() {
struct sigaction sa;
memset(&sa, 0, sizeof sa);
sa.sa_sigaction = ioHandler;
if (sigemptyset(&sa.sa_mask) < 0) {
die("sigemptyset");
}
sa.sa_flags = SA_SIGINFO;
if (sigaction(SIGIO, &sa, NULL) < 0) {
die("sigaction");
}
sa.sa_sigaction = segvHandler;
if (sigaction(SIGSEGV, &sa, NULL) < 0 || sigaction(SIGBUS, &sa, NULL) < 0) {
die("sigaction");
}
sa.sa_sigaction = pipeHandler;
if (sigaction(SIGPIPE, &sa, NULL) < 0) {
die("sigaction");
}
}
int main(int argc, char** argv) {
int verbose;
sigset_t mask;
int i;
struct timespec ts;
verbose = argc > 1;
setvbuf(stdout, NULL, _IONBF, 0);
// Call setsid so that we can use kill(0, SIGIO) below.
// Don't check the return value so that this works both from
// a job control shell and from a shell script.
setsid();
if (verbose) {
printf("calling RunGoroutines\n");
}
RunGoroutines();
// Block SIGIO in this thread to make it more likely that it
// will be delivered to a goroutine.
if (verbose) {
printf("calling pthread_sigmask\n");
}
if (sigemptyset(&mask) < 0) {
die("sigemptyset");
}
if (sigaddset(&mask, SIGIO) < 0) {
die("sigaddset");
}
i = pthread_sigmask(SIG_BLOCK, &mask, NULL);
if (i != 0) {
fprintf(stderr, "pthread_sigmask: %s\n", strerror(i));
exit(EXIT_FAILURE);
}
if (verbose) {
printf("calling kill\n");
}
if (kill(0, SIGIO) < 0) {
die("kill");
}
if (verbose) {
printf("waiting for sigioSeen\n");
}
// Wait until the signal has been delivered.
i = 0;
while (!sigioSeen) {
ts.tv_sec = 0;
ts.tv_nsec = 1000000;
nanosleep(&ts, NULL);
i++;
if (i > 5000) {
fprintf(stderr, "looping too long waiting for SIGIO\n");
exit(EXIT_FAILURE);
}
}
if (verbose) {
printf("provoking SIGPIPE\n");
}
GoRaiseSIGPIPE();
if (verbose) {
printf("waiting for sigpipeSeen\n");
}
// Wait until the signal has been delivered.
i = 0;
while (!sigpipeSeen) {
ts.tv_sec = 0;
ts.tv_nsec = 1000000;
nanosleep(&ts, NULL);
i++;
if (i > 5000) {
fprintf(stderr, "looping too long waiting for SIGPIPE\n");
exit(EXIT_FAILURE);
}
}
if (verbose) {
printf("calling setjmp\n");
}
// Test that a SIGSEGV on this thread is delivered to us.
if (setjmp(jmp) == 0) {
if (verbose) {
printf("triggering SIGSEGV\n");
}
*nullPointer = '\0';
fprintf(stderr, "continued after address error\n");
exit(EXIT_FAILURE);
}
if (verbose) {
printf("calling TestSEGV\n");
}
TestSEGV();
printf("PASS\n");
return 0;
}
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