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#include <sys/mman.h>
#include <sched.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/prctl.h>
#include <sys/user.h>
#include "zdtmtst.h"
const char *test_doc = "Create a crazy process tree";
const char *test_author = "Andrew Vagin <avagin@parallels.com>";
struct process
{
pid_t pid;
pid_t sid;
int sks[2];
int dead;
int wait;
};
#define MEM_SIZE (2 * PAGE_SIZE)
#define PR_MAX (MEM_SIZE / sizeof(struct process))
struct process *processes;
int nr_processes = 0;
int current = 0;
static void sigchld_handler(int signal, siginfo_t *siginfo, void *data)
{
pid_t pid = siginfo->si_pid;
if (siginfo->si_status == 2)
waitpid(pid, NULL, WNOHANG);
}
static void cleanup(void)
{
int i, ret;
for (i = 0; i < nr_processes; i++) {
if (processes[i].dead)
continue;
if (processes[i].pid <= 0)
continue;
kill(processes[i].pid, SIGKILL);
}
while (1) {
ret = wait(NULL);
if (ret == -1) {
if (errno == ECHILD)
break;
pr_perror("wait");
exit(1);
}
}
}
enum commands
{
TEST_FORK,
TEST_DIE_WAIT,
TEST_DIE,
TEST_SUBREAPER,
TEST_SETSID,
TEST_MAX
};
int cmd_weght[TEST_MAX] = {10, 3, 1, 10, 7};
int sum_weight = 0;
static int get_rnd_op(void)
{
int i, m;
if (sum_weight == 0) {
for (i = 0; i < TEST_MAX; i++)
sum_weight += cmd_weght[i];
}
m = lrand48() % sum_weight;
for (i = 0; i < TEST_MAX; i++) {
if (m > cmd_weght[i]) {
m -= cmd_weght[i];
continue;
}
return i;
}
return -1;
}
struct command
{
enum commands cmd;
int arg1;
int arg2;
};
static void handle_command(void);
static void mainloop(void)
{
while (1)
handle_command();
}
#define CLONE_STACK_SIZE 4096
/* All arguments should be above stack, because it grows down */
struct clone_args {
char stack[CLONE_STACK_SIZE] __stack_aligned__;
char stack_ptr[0];
int id;
};
static int clone_func(void *_arg)
{
struct clone_args *args = (struct clone_args *) _arg;
current = args->id;
test_msg("%3d: Hello. My pid is %d\n", args->id, getpid());
mainloop();
exit(0);
}
static int make_child(int id, int flags)
{
struct clone_args args;
pid_t cid;
args.id = id;
cid = clone(clone_func, args.stack_ptr,
flags | SIGCHLD, &args);
if (cid < 0)
pr_perror("clone(%d, %d)", id, flags);
processes[id].pid = cid;
return cid;
}
static void handle_command(void)
{
int sk = processes[current].sks[0], ret, status = 0;
struct command cmd;
ret = read(sk, &cmd, sizeof(cmd));
if (ret != sizeof(cmd)) {
pr_perror("Unable to get command");
goto err;
}
switch (cmd.cmd) {
case TEST_FORK:
{
pid_t pid;
pid = make_child(cmd.arg1, cmd.arg2 ? CLONE_PARENT : 0);
if (pid < 0) {
status = -1;
goto err;
}
test_msg("%3d: fork(%d, %x) = %d\n",
current, cmd.arg1, cmd.arg2, pid);
processes[cmd.arg1].pid = pid;
}
break;
case TEST_SUBREAPER:
test_msg("%3d: subreaper(%d)\n", current, cmd.arg1);
if (prctl(PR_SET_CHILD_SUBREAPER, cmd.arg1, 0, 0, 0) == -1) {
pr_perror("PR_SET_CHILD_SUBREAPER");
status = -1;
}
break;
case TEST_SETSID:
if (getsid(0) == getpid())
break;
test_msg("%3d: setsid()\n", current);
if(setsid() == -1) {
pr_perror("setsid");
status = -1;
}
break;
case TEST_DIE_WAIT:
test_msg("%3d: wait()\n", current);
case TEST_DIE:
test_msg("%3d: die()\n", current);
processes[current].dead = 1;
shutdown(sk, SHUT_RDWR);
if (cmd.cmd == TEST_DIE_WAIT)
exit(2);
exit(0);
default:
pr_perror("Unknown operation %d", cmd.cmd);
status = -1;
break;
}
ret = write(sk, &status, sizeof(status));
if (ret != sizeof(status)) {
pr_perror("Unable to answer");
goto err;
}
if (status < 0)
goto err;
return;
err:
shutdown(sk, SHUT_RDWR);
exit(1);
}
static int send_command(int id, enum commands op, int arg)
{
int sk = processes[id].sks[1], ret, status;
struct command cmd = {op, arg};
if (op == TEST_FORK) {
cmd.arg1 = nr_processes;
nr_processes++;
if (nr_processes > PR_MAX)
return -1;
cmd.arg2 = arg;
}
ret = write(sk, &cmd, sizeof(cmd));
if (ret != sizeof(cmd)) {
pr_perror("Unable to send command");
goto err;
}
status = 0;
ret = read(sk, &status, sizeof(status));
if (ret != sizeof(status) &&
!(status == 0 && (op == TEST_DIE || op == TEST_DIE_WAIT))) {
pr_perror("Unable to get answer");
goto err;
}
if (status) {
pr_perror("The command(%d, %d) failed", op, arg);
goto err;
}
return 0;
err:
cleanup();
exit(1);
}
int main(int argc, char ** argv)
{
struct sigaction act;
int pid, i, ret;
int fail_cnt = 0;
test_init(argc, argv);
if (prctl(PR_SET_CHILD_SUBREAPER, 1, 0, 0, 0) == -1) {
pr_perror("PR_SET_CHILD_SUBREAPER");
return -1;
}
ret = sigaction(SIGCHLD, NULL, &act);
if (ret < 0) {
pr_perror("sigaction() failed");
return -1;
}
act.sa_flags |= SA_NOCLDSTOP | SA_SIGINFO | SA_RESTART;
act.sa_sigaction = sigchld_handler;
sigemptyset(&act.sa_mask);
sigaddset(&act.sa_mask, SIGCHLD);
ret = sigaction(SIGCHLD, &act, NULL);
if (ret < 0) {
pr_perror("sigaction() failed");
return -1;
}
processes = mmap(NULL, MEM_SIZE, PROT_WRITE | PROT_READ,
MAP_SHARED | MAP_ANONYMOUS, 0, 0);
if (processes == NULL) {
pr_perror("Unable to map share memory");
return 1;
}
for (i = 0; i < PR_MAX; i++) {
if (socketpair(PF_UNIX, SOCK_STREAM, 0, processes[i].sks) == -1) {
pr_perror("socketpair");
return 1;
}
}
nr_processes++;
pid = make_child(0, 0);
if (pid < 0)
return -1;
while(nr_processes < PR_MAX) {
int op, id;
int flags = lrand48() % 2;
op = get_rnd_op();
if (op == TEST_DIE || op == TEST_DIE_WAIT || op == TEST_SUBREAPER) {
if (nr_processes == 1)
continue;
else
id = lrand48() % (nr_processes - 1) + 1;
} else if (op == TEST_FORK) {
id = nr_processes * 9 / 10 + lrand48() % nr_processes / 10;
while (processes[id].dead != 0)
id--;
} else
id = lrand48() % nr_processes;
if (processes[id].dead)
continue;
send_command(id, op, flags);
}
for (i = 0; i < nr_processes; i++) {
if (processes[i].dead)
continue;
if (processes[i].pid == 0)
continue;
processes[i].sid = getsid(processes[i].pid);
if (processes[i].sid == -1) {
pr_perror("getsid(%d)", i);
goto err;
}
}
test_daemon();
test_waitsig();
for (i = 0; i < nr_processes; i++) {
pid_t sid;
if (processes[i].dead)
continue;
if (processes[i].pid == 0)
continue;
sid = getsid(processes[i].pid);
if (sid == -1) {
pr_perror("getsid(%d)", i);
goto err;
}
if (sid != processes[i].sid) {
fail("%d, %d: wrong sid %d (expected %d)",
i, processes[i].pid, sid, processes[i].sid);
fail_cnt++;
}
}
if (fail_cnt)
goto err;
pass();
cleanup();
return 0;
err:
cleanup();
return 1;
}
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