Changes from v4:
* Rebased against master.
--
It is a wrapper for Linux clone syscall, to simplify the call to the
use only the most common arguments and remove architecture specific
handling (such as ia64 different name and signature).
---
support/Makefile | 1 +
support/xclone.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
support/xsched.h | 34 ++++++++++++++++++++++++++++++++
3 files changed, 85 insertions(+)
create mode 100644 support/xclone.c
create mode 100644 support/xsched.h
@@ -96,6 +96,7 @@ libsupport-routines = \
xchroot \
xclock_gettime \
xclock_settime \
+ xclone \
xclose \
xchmod \
xconnect \
new file mode 100644
@@ -0,0 +1,50 @@
+/* Auxiliary functions to issue the clone syscall.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library 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.
+
+ The GNU C Library 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 the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifdef __linux__
+# include <support/check.h>
+# include <stackinfo.h> /* For _STACK_GROWS_{UP,DOWN}. */
+# include <xsched.h>
+
+pid_t
+xclone (int (*fn) (void *arg), void *arg, void *stack, size_t stack_size,
+ int flags)
+{
+ pid_t r = -1;
+
+# ifdef __ia64__
+ extern int __clone2 (int (*fn) (void *arg), void *stack, size_t stack_size,
+ int flags, void *arg, ...);
+ r = __clone2 (f, stack, stack_size, flags, arg, /* ptid */ NULL,
+ /* tls */ NULL, /* ctid */ ctid);
+# else
+# if _STACK_GROWS_DOWN
+ r = clone (fn, stack + stack_size, flags, arg, /* ptid */ NULL,
+ /* tls */ NULL, /* ctid */ NULL);
+# elif _STACK_GROWS_UP
+ r = clone (fn, stack, flags, arg, /* ptid */ NULL, /* tls */ NULL,
+ &ctid);
+# endif
+# endif
+
+ if (r < 0)
+ FAIL_EXIT1 ("clone: %m");
+
+ return r;
+}
+#endif
new file mode 100644
@@ -0,0 +1,34 @@
+/* Wrapper for sched.h functions.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library 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.
+
+ The GNU C Library 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 the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef SUPPORT_XSCHED_H
+#define SUPPORT_XSCHED_H
+
+__BEGIN_DECLS
+
+#include <sched.h>
+#include <sys/types.h>
+
+#ifdef __linux__
+pid_t xclone (int (*fn) (void *arg), void *arg, void *stack,
+ size_t stack_size, int flags);
+#endif
+
+__END_DECLS
+
+#endif