+/* SPDX-License-Identifier: LGPL-2.1+ */
#pragma once
/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
Copyright 2016 Michael Karcher
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+//#include <errno.h>
#include <sched.h>
#include <sys/syscall.h>
* raw_clone() - uses clone to create a new process with clone flags
* @flags: Flags to pass to the clone system call
*
- * Uses the clone system call to create a new process with the cloning
- * flags and termination signal passed in the flags parameter. Opposed
- * to glibc's clone funtion, using this function does not set up a
- * separate stack for the child, but relies on copy-on-write semantics
- * on the one stack at a common virtual address, just as fork does.
+ * Uses the clone system call to create a new process with the cloning flags and termination signal passed in the flags
+ * parameter. Opposed to glibc's clone funtion, using this function does not set up a separate stack for the child, but
+ * relies on copy-on-write semantics on the one stack at a common virtual address, just as fork does.
*
- * To obtain copy-on-write semantics, flags must not contain CLONE_VM,
- * and thus CLONE_THREAD and CLONE_SIGHAND (which require CLONE_VM) are
- * not usabale.
- * Additionally, as this function does not pass the ptid, newtls and ctid
- * parameters to the kernel, flags must not contain CLONE_PARENT_SETTID,
- * CLONE_CHILD_SETTID, CLONE_CHILD_CLEARTID or CLONE_SETTLS.
+ * To obtain copy-on-write semantics, flags must not contain CLONE_VM, and thus CLONE_THREAD and CLONE_SIGHAND (which
+ * require CLONE_VM) are not usable.
+ *
+ * Additionally, as this function does not pass the ptid, newtls and ctid parameters to the kernel, flags must not
+ * contain CLONE_PARENT_SETTID, CLONE_CHILD_SETTID, CLONE_CHILD_CLEARTID or CLONE_SETTLS.
*
* Returns: 0 in the child process and the child process id in the parent.
*/
-static inline int raw_clone(unsigned long flags) {
+static inline pid_t raw_clone(unsigned long flags) {
+ pid_t ret;
+
assert((flags & (CLONE_VM|CLONE_PARENT_SETTID|CLONE_CHILD_SETTID|
CLONE_CHILD_CLEARTID|CLONE_SETTLS)) == 0);
-#if defined(__s390__) || defined(__CRIS__)
- /* On s390 and cris the order of the first and second arguments
+#if defined(__s390x__) || defined(__s390__) || defined(__CRIS__)
+ /* On s390/s390x and cris the order of the first and second arguments
* of the raw clone() system call is reversed. */
- return (int) syscall(__NR_clone, NULL, flags);
-#elif defined(__sparc__) && defined(__arch64__)
+ ret = (pid_t) syscall(__NR_clone, NULL, flags);
+#elif defined(__sparc__)
{
/**
- * sparc64 always returns the other process id in %o0, and
+ * sparc always returns the other process id in %o0, and
* a boolean flag whether this is the child or the parent in
* %o1. Inline assembly is needed to get the flag returned
* in %o1.
*/
- int in_child;
- int child_pid;
- asm volatile("mov %2, %%g1\n\t"
- "mov %3, %%o0\n\t"
+ int in_child, child_pid, error;
+
+ asm volatile("mov %3, %%g1\n\t"
+ "mov %4, %%o0\n\t"
"mov 0 , %%o1\n\t"
+#if defined(__arch64__)
"t 0x6d\n\t"
+#else
+ "t 0x10\n\t"
+#endif
+ "addx %%g0, 0, %2\n\t"
"mov %%o1, %0\n\t"
"mov %%o0, %1" :
- "=r"(in_child), "=r"(child_pid) :
+ "=r"(in_child), "=r"(child_pid), "=r"(error) :
"i"(__NR_clone), "r"(flags) :
- "%o1", "%o0", "%g1" );
- if (in_child)
- return 0;
- else
- return child_pid;
+ "%o1", "%o0", "%g1" "cc" );
+
+ if (error) {
+ errno = child_pid;
+ ret = -1;
+ } else
+ ret = in_child ? 0 : child_pid;
}
#else
- return (int) syscall(__NR_clone, flags, NULL);
+ ret = (pid_t) syscall(__NR_clone, flags, NULL);
#endif
+
+ if (ret == 0)
+ reset_cached_pid();
+
+ return ret;
}