glebfm/strace
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

test/threaded_execve: make it also test a case when leader is not in syscall

Browse Source 
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2012-03-17 01:24:25 +01:00
parent b468f2320a
commit cb419c52cb
1 changed files with 22 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
test/threaded_execve.c
View File

@ -10,24 +10,24 @@
*
* # Should not be confused by traced execve-ing thread
* # replacing traced leader:
* [LEADER_EXIT=1] strace -oLOG -f ./threaded_execve
* strace -oLOG -f ./threaded_execve
*
* # Same, but different output mode. Output after execve
* # should go into leader's LOG.<pid> file, not into execve'ed
* # thread's log file:
* [LEADER_EXIT=1] strace -oLOG -ff ./threaded_execve
* strace -oLOG -ff ./threaded_execve
*
* # Should not be confused by non-traced execve-ing thread
* # replacing traced leader:
* [LEADER_EXIT=1] strace -oLOG ./threaded_execve
* ^^^^^^^^^^^^^^^^^^^^^
* strace -oLOG ./threaded_execve
* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* In Linux 3.2, non-traced execve-ing thread does not
* become traced after execve, even though it has pid == leader's pid
* after execve. And yet, strace's waitpid doesn't return ECHILD.
*
* # Run for NUM seconds, not just one second.
* # Watch top to check for memory leaks in strace:
* [LEADER_EXIT=1] strace -oLOG -f ./threaded_execve <NUM>
* strace -oLOG -f ./threaded_execve <NUM>
*
*/
#define NUM_THREADS 1
@ -65,6 +65,7 @@ extern int __clone2(int (*fn) (void *), void *child_stack_base,
#define syscall_exit(v) syscall(__NR_exit, (v));
static char my_name[PATH_MAX];
static int leader_final_action;
static int
thread1(void *unused)
@ -77,18 +78,20 @@ thread1(void *unused)
static int
thread2(void *unused)
{
char buf[64];
sprintf(buf, "%d", leader_final_action);
write(1, "2", 1);
usleep(20*1000);
/* This fails with ENOENT if leader has exited by now! :) */
execl("/proc/self/exe", "exe", "exe", NULL);
execl("/proc/self/exe", "exe", "exe", buf, NULL);
/* So fall back to resolved name */
execl(my_name, "exe", "exe", NULL);
execl(my_name, "exe", "exe", buf, NULL);
for(;;) pause();
return 0;
}
static void
thread_leader(int die)
thread_leader(void)
{
/* malloc gives sufficiently aligned buffer.
* long buf[] does not! (on ia64).
@ -111,27 +114,31 @@ thread_leader(int die)
| 0 /* no signal to send on death */
, NULL);
if (die) syscall_exit(42);
for(;;) pause();
/* Various states leader can be while other thread execve's: */
switch (leader_final_action % 3) {
case 0: syscall_exit(42); /* leader is dead */
case 1: for(;;) pause(); /* leader is in syscall */
default: for(;;) continue; /* leader is in userspace */
}
}
int
main(int argc, char **argv)
{
int die = getenv("LEADER_EXIT") != NULL;
if (readlink("/proc/self/exe", my_name, sizeof(my_name)-1) <= 0)
return 1;
setbuf(stdout, NULL);
if (argv[1] && strcmp(argv[1], "exe") == 0)
thread_leader(die);
if (argv[1] && strcmp(argv[1], "exe") == 0) {
leader_final_action = atoi(argv[2]) + 1;
thread_leader();
}
printf("%d: thread leader\n", getpid());
alarm(argv[1] ? atoi(argv[1]) : 1);
thread_leader(die);
thread_leader();
return 0;
}