tree-wide: remove Lennart's copyright lines

[elogind.git] / src / basic / raw-clone.h

diff --git a/src/basic/raw-clone.h b/src/basic/raw-clone.h
index 1bef6f2dae0c50394483b734fce11a44e3885d7b..fb427f5d8d7510808947fdbf80adde1c84600a34 100644 (file)
--- a/src/basic/raw-clone.h
+++ b/src/basic/raw-clone.h
@@ -1,24 +1,11 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
 #pragma once
 
 /***
-  This file is part of elogind.
-
-  Copyright 2010 Lennart Poettering
   Copyright 2016 Michael Karcher
-  elogind 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.
-
-  elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+//#include <errno.h>
 #include <sched.h>
 #include <sys/syscall.h>
 
@@ -29,53 +16,64 @@
  * 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;
 }