mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-15 19:02:04 +00:00
108 lines
2.6 KiB
C
108 lines
2.6 KiB
C
|
/// Very limited implementation. Half of code from Musl was cut.
|
||
|
|
/// This is Ok, because for now, this function is used only from clang driver.
|
||
|
|
|
||
|
|
#define _GNU_SOURCE
|
||
|
|
#include <spawn.h>
|
||
|
|
#include <sched.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
#include <signal.h>
|
||
|
|
#include <fcntl.h>
|
||
|
|
#include <sys/wait.h>
|
||
|
|
#include <syscall.h>
|
||
|
|
#include <sys/signal.h>
|
||
|
|
#include <pthread.h>
|
||
|
|
#include <spawn.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include "syscall.h"
|
||
|
|
|
||
|
|
struct args {
|
||
|
|
int p[2];
|
||
|
|
sigset_t oldmask;
|
||
|
|
const char *path;
|
||
|
|
int (*exec)(const char *, char *const *, char *const *);
|
||
|
|
const posix_spawn_file_actions_t *fa;
|
||
|
|
const posix_spawnattr_t *restrict attr;
|
||
|
|
char *const *argv, *const *envp;
|
||
|
|
};
|
||
|
|
|
||
|
|
void __get_handler_set(sigset_t *);
|
||
|
|
|
||
|
|
static int child(void *args_vp)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
struct args *args = args_vp;
|
||
|
|
int p = args->p[1];
|
||
|
|
const posix_spawnattr_t *restrict attr = args->attr;
|
||
|
|
|
||
|
|
close(args->p[0]);
|
||
|
|
|
||
|
|
/* Close-on-exec flag may have been lost if we moved the pipe
|
||
|
|
* to a different fd. We don't use F_DUPFD_CLOEXEC above because
|
||
|
|
* it would fail on older kernels and atomicity is not needed --
|
||
|
|
* in this process there are no threads or signal handlers. */
|
||
|
|
__syscall(SYS_fcntl, p, F_SETFD, FD_CLOEXEC);
|
||
|
|
|
||
|
|
pthread_sigmask(SIG_SETMASK, (attr->__flags & POSIX_SPAWN_SETSIGMASK)
|
||
|
|
? &attr->__ss : &args->oldmask, 0);
|
||
|
|
|
||
|
|
args->exec(args->path, args->argv, args->envp);
|
||
|
|
ret = -errno;
|
||
|
|
|
||
|
|
/* Since sizeof errno < PIPE_BUF, the write is atomic. */
|
||
|
|
ret = -ret;
|
||
|
|
if (ret) while (__syscall(SYS_write, p, &ret, sizeof ret) < 0);
|
||
|
|
_exit(127);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int __posix_spawnx(pid_t *restrict res, const char *restrict path,
|
||
|
|
int (*exec)(const char *, char *const *, char *const *),
|
||
|
|
const posix_spawn_file_actions_t *fa,
|
||
|
|
const posix_spawnattr_t *restrict attr,
|
||
|
|
char *const argv[restrict], char *const envp[restrict])
|
||
|
|
{
|
||
|
|
pid_t pid;
|
||
|
|
char stack[1024];
|
||
|
|
int ec=0, cs;
|
||
|
|
struct args args;
|
||
|
|
|
||
|
|
if (pipe2(args.p, O_CLOEXEC))
|
||
|
|
return errno;
|
||
|
|
|
||
|
|
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
|
||
|
|
|
||
|
|
args.path = path;
|
||
|
|
args.exec = exec;
|
||
|
|
args.fa = fa;
|
||
|
|
args.attr = attr ? attr : &(const posix_spawnattr_t){0};
|
||
|
|
args.argv = argv;
|
||
|
|
args.envp = envp;
|
||
|
|
|
||
|
|
pid = clone(child, stack+sizeof stack,
|
||
|
|
CLONE_VM|CLONE_VFORK|SIGCHLD, &args);
|
||
|
|
close(args.p[1]);
|
||
|
|
|
||
|
|
if (pid > 0) {
|
||
|
|
if (read(args.p[0], &ec, sizeof ec) != sizeof ec) ec = 0;
|
||
|
|
else waitpid(pid, &(int){0}, 0);
|
||
|
|
} else {
|
||
|
|
ec = -pid;
|
||
|
|
}
|
||
|
|
|
||
|
|
close(args.p[0]);
|
||
|
|
|
||
|
|
if (!ec && res) *res = pid;
|
||
|
|
|
||
|
|
pthread_setcancelstate(cs, 0);
|
||
|
|
|
||
|
|
return ec;
|
||
|
|
}
|
||
|
|
|
||
|
|
int posix_spawn(pid_t *restrict res, const char *restrict path,
|
||
|
|
const posix_spawn_file_actions_t *fa,
|
||
|
|
const posix_spawnattr_t *restrict attr,
|
||
|
|
char *const argv[restrict], char *const envp[restrict])
|
||
|
|
{
|
||
|
|
return __posix_spawnx(res, path, execve, fa, attr, argv, envp);
|
||
|
|
}
|