strace/tests/ipc_sem.c
Dmitry V. Levin 499c5aad0c semctl: fix indirect syscall decoding
On architectures where the semctl call is implemented by the ipc syscall
the 4th argument is passed by reference.

* ipc.c (sys_semctl): Handle the indirect ipc subcall case.
* tests/ipc_sem.c (main): Optionally match indirection
in the 4th argument of semctl calls.

Reported-by: Andreas Schwab <schwab@suse.de>
2015-03-16 14:23:09 +00:00

66 lines
1.5 KiB
C

#include <stdio.h>
#include <errno.h>
#include <sys/sem.h>
union semun {
int val; /* Value for SETVAL */
struct semid_ds *buf; /* Buffer for IPC_STAT, IPC_SET */
unsigned short *array; /* Array for GETALL, SETALL */
struct seminfo *__buf; /* Buffer for IPC_INFO
(Linux-specific) */
};
int
main(void)
{
int rc, id;
union semun un;
struct semid_ds ds;
struct seminfo info;
id = semget(IPC_PRIVATE, 1, 0600);
if (id < 0)
return 77;
printf("semget\\(IPC_PRIVATE, 1, 0600\\) += %d\n", id);
un.buf = &ds;
if (semctl(id, 0, IPC_STAT, un))
goto fail;
printf("semctl\\(%d, 0, (IPC_64\\|)?IPC_STAT, \\[?%p\\]?\\) += 0\n",
id, &ds);
un.__buf = &info;
int max = semctl(0, 0, SEM_INFO, un);
if (max < 0)
goto fail;
printf("semctl\\(0, 0, (IPC_64\\|)?SEM_INFO, \\[?%p\\]?\\) += %d\n",
&info, max);
un.buf = &ds;
rc = semctl(id, 0, SEM_STAT, un);
if (rc != id) {
/*
* In linux < v2.6.24-rc1 the first argument must be
* an index in the kernel's internal array.
*/
if (-1 != rc || EINVAL != errno)
goto fail;
printf("semctl\\(%d, 0, (IPC_64\\|)?SEM_STAT, \\[?%p\\]?\\)"
" += -1 EINVAL \\(Invalid argument\\)\n", id, &ds);
} else {
printf("semctl\\(%d, 0, (IPC_64\\|)?SEM_STAT, \\[?%p\\]?\\)"
" += %d\n", id, &ds, id);
}
rc = 0;
done:
if (semctl(id, 0, IPC_RMID, 0) < 0)
return 1;
printf("semctl\\(%d, 0, (IPC_64\\|)?IPC_RMID, \\[?0\\]?\\) += 0\n", id);
return rc;
fail:
rc = 1;
goto done;
}