#define _GNU_SOURCE
#include <errno.h>
#include <poll.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#include "live.h"
#include "livebus.h"

typedef struct Test Test;

struct Test
{
	Live l;
	Daemon first;
	Daemon second;
	int ipcfirst;
	int ipcnew;
	DBusConnection *busfirst;
	DBusConnection *busnew;
	char address[512];
};

static int
setup(Test *t)
{
	memset(t, 0, sizeof *t);
	daemoninit(&t->first, "first daemon");
	daemoninit(&t->second, "second daemon");
	t->ipcfirst = -1;
	t->ipcnew = -1;
	return livesetup(&t->l, "collision");
}

static int
addressunchanged(Test *t)
{
	char contents[2048], address[512];
	size_t ncontents;
	pid_t declared;

	if(!readfile(t->l.addrfile, contents, sizeof contents, &ncontents) ||
	   !parseaddress(contents, ncontents, address, sizeof address, &declared))
		return 0;
	if(declared != t->first.pid)
		return fail("IBus address PID %ld, expected %ld", (long)declared,
			(long)t->first.pid);
	return strcmp(address, t->address) == 0 ||
		fail("first private IBus address changed after collision");
}

static int
waitsecond(Test *t)
{
	struct pollfd pfd;
	int n, status, timeout;
	int64_t deadline;

	deadline = nowms() + Starttimeout;
	for(;;){
		do
			n = waitpid(t->second.pid, &status, WNOHANG);
		while(n < 0 && errno == EINTR);
		if(n == t->second.pid){
			t->second.pid = -1;
			readerrors(&t->second);
			if(!WIFEXITED(status) || WEXITSTATUS(status) == 0)
				return fail("second daemon did not exit unsuccessfully: %#x",
					status);
			if(strstr(t->second.err, "IPC endpoint is already in use") == NULL)
				return fail("second daemon did not report the IPC collision");
			return 1;
		}
		if(n < 0){
			fail("waitpid second daemon %ld: %s", (long)t->second.pid,
				strerror(errno));
			if(errno == ECHILD)
				t->second.pid = -1;
			return 0;
		}
		if(!daemonalive(&t->first))
			return 0;
		timeout = leftms(deadline);
		if(timeout == 0){
			fail("second daemon did not exit after the endpoint collision");
			killdaemon(&t->second, NULL);
			return 0;
		}
		pfd.fd = t->second.errfd;
		pfd.events = POLLIN|POLLHUP;
		pfd.revents = 0;
		n = poll(&pfd, 1, timeout > 20 ? 20 : timeout);
		if(n < 0 && errno == EINTR)
			continue;
		if(n < 0)
			return fail("poll second daemon: %s", strerror(errno));
		if(pfd.revents != 0)
			readerrors(&t->second);
	}
}

static int
runcollision(Test *t, char *program, char *mapdir)
{
	if(!startdaemon(&t->l, &t->first, program, mapdir) ||
	   !waitready(&t->l, &t->first, t->address, sizeof t->address))
		return 0;
	t->ipcfirst = connectsocket(t->l.socket, nowms() + Calltimeout);
	if(t->ipcfirst < 0)
		return fail("connect persistent IPC client: %s", strerror(errno));
	if(!ipcprobe(t->ipcfirst, "persistent pre-collision"))
		return 0;
	t->busfirst = openbus(t->address, "persistent pre-collision");
	if(t->busfirst == NULL ||
	   !hello(t->busfirst, NULL, 0, "persistent pre-collision Hello"))
		return 0;
	if(!startdaemon(&t->l, &t->second, program, mapdir) ||
	   !waitsecond(t) || !daemonalive(&t->first) || !addressunchanged(t))
		return 0;
	if(!ipcprobe(t->ipcfirst, "persistent post-collision"))
		return 0;
	if(!createcontext(t->busfirst, NULL, 0,
	   "persistent post-collision context"))
		return 0;
	t->ipcnew = connectsocket(t->l.socket, nowms() + Calltimeout);
	if(t->ipcnew < 0)
		return fail("connect new IPC client after collision: %s",
			strerror(errno));
	if(!ipcprobe(t->ipcnew, "new post-collision"))
		return 0;
	t->busnew = openbus(t->address, "new post-collision");
	if(t->busnew == NULL ||
	   !hello(t->busnew, NULL, 0, "new post-collision Hello") ||
	   !createcontext(t->busnew, NULL, 0, "new post-collision context"))
		return 0;
	return daemonalive(&t->first);
}

static int
cleanup(Test *t)
{
	int n, ok, status;

	ok = 1;
	closebus(&t->busnew);
	closebus(&t->busfirst);
	if(t->ipcnew >= 0){
		if(close(t->ipcnew) < 0)
			ok = fail("close new IPC client: %s", strerror(errno));
		t->ipcnew = -1;
	}
	if(t->ipcfirst >= 0){
		if(close(t->ipcfirst) < 0)
			ok = fail("close persistent IPC client: %s", strerror(errno));
		t->ipcfirst = -1;
	}
	if(t->second.pid > 0){
		do
			n = waitpid(t->second.pid, &status, WNOHANG);
		while(n < 0 && errno == EINTR);
		if(n == t->second.pid)
			t->second.pid = -1;
		else if(n == 0){
			ok = fail("second daemon still running during cleanup");
			if(!killdaemon(&t->second, NULL))
				ok = 0;
		}else{
			fail("check second daemon during cleanup: %s", strerror(errno));
			ok = 0;
			if(errno == ECHILD)
				t->second.pid = -1;
			else if(!killdaemon(&t->second, NULL))
				ok = 0;
		}
	}
	if(!stopdaemon(&t->first))
		ok = 0;
	if(!closeerrors(&t->first))
		ok = 0;
	if(!closeerrors(&t->second))
		ok = 0;
	if(!liveclean(&t->l))
		ok = 0;
	return ok;
}

int
main(int argc, char **argv)
{
	Test test;
	int ok;

	testname = "daemon_collision_test";
	if(argc != 3){
		fprintf(stderr, "usage: daemon_collision_test strans mapdir\n");
		return 2;
	}
	ok = setup(&test);
	if(ok)
		ok = runcollision(&test, argv[1], argv[2]);
	if(!cleanup(&test))
		ok = 0;
	if(!ok){
		showerrors(&test.first);
		showerrors(&test.second);
		return 1;
	}
	printf("daemon endpoint collision ownership: ok\n");
	return 0;
}