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/* COVERAGE: clone wait4 */
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <sched.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sys/syscall.h>
static int child_fn(void *arg)
{
exit(0);
}
#define STACK_SIZE (1024 * 1024) /* Stack size for cloned child */
/* For limit testing, we need the raw syscalls. */
#if defined(__ia64__) && defined(SYS_clone2)
static inline int
__sys_clone2(int flags, void *ustack_base, size_t ustack_size,
void *parent_tidptr, void *child_tidptr, void *tls)
{
return syscall(SYS_clone2, flags, ustack_base, ustack_size, parent_tidptr,
child_tidptr, tls);
}
#endif
#ifdef SYS_clone
// The main kernel config file says that clone comes from the "ABI
// hall of shame". Here's why. clone differs in the order of arguments
// between architectures. Here's the kernel code:
//
// #ifdef CONFIG_CLONE_BACKWARDS
// SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
// int __user *, parent_tidptr,
// int, tls_val,
// int __user *, child_tidptr)
// #elif defined(CONFIG_CLONE_BACKWARDS2)
// SYSCALL_DEFINE5(clone, unsigned long, newsp, unsigned long, clone_flags,
// int __user *, parent_tidptr,
// int __user *, child_tidptr,
// int, tls_val)
// #elif defined(CONFIG_CLONE_BACKWARDS3)
// SYSCALL_DEFINE6(clone, unsigned long, clone_flags, unsigned long, newsp,
// int, stack_size,
// int __user *, parent_tidptr,
// int __user *, child_tidptr,
// int, tls_val)
// #else
// SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
// int __user *, parent_tidptr,
// int __user *, child_tidptr,
// int, tls_val)
// #endif
//
// Note that systemtap actually probes do_fork(), which doesn't get
// the tls_val.
#if defined(__s390__) || defined(__s390x__)
#define CLONE_BACKWARDS2
#endif
#if defined(__powerpc__) || defined(__powerpc64__) \
|| defined(__arm__) || defined(__aarch64__) \
|| defined(__i386__)
#define CLONE_BACKWARDS
#endif
static inline long
__clone(unsigned long flags, void *child_stack, void *ptid, void *ctid,
int tls_val)
{
#ifdef CLONE_BACKWARDS
return syscall(SYS_clone, flags, child_stack, ptid, tls_val, ctid);
#elif defined(CLONE_BACKWARDS2)
return syscall(SYS_clone, child_stack, flags, ptid, ctid, tls_val);
#elif defined(CLONE_BACKWARDS3)
return syscall(SYS_clone, flags, child_stack, 0, ptid, ctid, tls_val);
#else
return syscall(SYS_clone, flags, child_stack, ptid, ctid, tls_val);
#endif
}
#endif
int
main()
{
char *stack;
char *stackTop;
pid_t pid;
stack = malloc(STACK_SIZE);
stackTop = stack + STACK_SIZE; /* Assume stack grows downward */
#if defined(__ia64__)
pid = __clone2(child_fn, stack, STACK_SIZE, SIGCHLD);
//staptest// clone2 (0x0|SIGCHLD, XXXX, 0x100000, XXXX, XXXX) = NNNN
#else
pid = clone(child_fn, stackTop, SIGCHLD, NULL);
//staptest// clone (0x0|SIGCHLD, XXXX, XXXX, XXXX) = NNNN
#endif
wait4(pid, NULL, 0, NULL); /* Wait for child */
//staptest// wait4 (NNNN, 0x0, 0x0, 0x0) = NNNN
#if defined(__ia64__)
pid = __clone2(child_fn, stack, STACK_SIZE, SIGCHLD);
//staptest// clone2 (0x0|SIGCHLD, XXXX, 0x100000, XXXX, XXXX) = NNNN
#else
pid = clone(child_fn, stackTop, SIGCHLD, NULL);
//staptest// clone (0x0|SIGCHLD, XXXX, XXXX, XXXX) = NNNN
#endif
wait4(pid, NULL, 0, NULL); /* Wait for child */
//staptest// wait4 (NNNN, 0x0, 0x0, 0x0) = NNNN
/* Limit testing. BTW, we want all these calls to fail, since we
* aren't cleaning up the child processes. */
#if defined(__ia64__) && defined(SYS_clone2)
// Keep sending an invalid flag value so all calls will fail.
pid = __sys_clone2(-1, NULL, 0, NULL, NULL, NULL);
//staptest// clone2 (CLONE_[^ ]+|XXXX, 0x0, 0x0, 0x0, 0x0) = -NNNN
pid = __sys_clone2(-1, (void *)-1, 0, NULL, NULL, NULL);
//staptest// clone2 (CLONE_[^ ]+|XXXX, 0x[f]+, 0x0, 0x0, 0x0) = -NNNN
pid = __sys_clone2(-1, NULL, -1, NULL, NULL, NULL);
//staptest// clone2 (CLONE_[^ ]+|XXXX, 0x0, 0x[f]+, 0x0, 0x0) = -NNNN
pid = __sys_clone2(-1, NULL, 0, (void *)-1, NULL, NULL);
//staptest// clone2 (CLONE_[^ ]+|XXXX, 0x0, 0x0, 0x[f]+, 0x0) = -NNNN
pid = __sys_clone2(-1, NULL, 0, NULL, (void *)-1, NULL);
//staptest// clone2 (CLONE_[^ ]+|XXXX, 0x0, 0x0, 0x0, 0x[f]+) = -NNNN
#endif
#ifdef SYS_clone
// We've got a bit of a problem here. On RHEL6, if you don't
// pass a stack pointer, the kernel uses a register value as a
// stack pointer. So, we'll pass an invalid value (1) for a stack
// pointer. Sigh, except that rawhide
// (4.0.0-0.rc3.git0.1.fc23.x86_64) needs a real stack pointer or
// this test program will crash.
pid = __clone((unsigned long)-1, stackTop, NULL, NULL, 0);
// On a 32-bit kernel, the full clone flags will overflow
// MAXSTRINGLEN.
//staptest// clone (CLONE_[^ ]+[[[[ ?!!!!|XXXX, XXXX, 0x0, 0x0]]]]?) = -NNNN
// Keep sending an invalid flag value so all calls will fail. But,
// sending a -1 will cause all the flags to be set, overflowing
// MAXSTRINGLEN. So, we'll use a different invalid flag value. You
// can't specify CLONE_NEWNS (new mount namespace group) and CLONE_FS
// (share filesystem info between processes) together.
// Unfortunately, on 4.0.0-0.rc3.git0.1.fc23.x86_64 passing -1 for
// a stack pointer causes the test executable to get a
// segmentation fault. So, we'll skip this one.
//
// pid = __clone(CLONE_FS|CLONE_NEWNS, (void *)-1, NULL, NULL, 0);
pid = __clone(CLONE_FS|CLONE_NEWNS, stackTop, (void *)-1, NULL, 0);
#ifdef __s390__
//staptest// clone (CLONE_FS|CLONE_NEWNS, XXXX, 0x[7]?[f]+, 0x0) = -NNNN
#else
//staptest// clone (CLONE_FS|CLONE_NEWNS, XXXX, 0x[f]+, 0x0) = -NNNN
#endif
pid = __clone(CLONE_FS|CLONE_NEWNS, stackTop, NULL, (void *)-1, 0);
#ifdef __s390__
//staptest// clone (CLONE_FS|CLONE_NEWNS, XXXX, 0x0, 0x[7]?[f]+) = -NNNN
#else
//staptest// clone (CLONE_FS|CLONE_NEWNS, XXXX, 0x0, 0x[f]+) = -NNNN
#endif
#endif
return 0;
}
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