raw_syscalls: add lxc_raw_clone{_cb}()

[mirror_lxc.git] / src / lxc / namespace.h

diff --git a/src/lxc/namespace.h b/src/lxc/namespace.h
index e35de60bc82c62893a1afdde3c2d5234e72f9932..be2bf8b7133281abd58cb6dd486152ec96b11c2a 100644 (file)
--- a/src/lxc/namespace.h
+++ b/src/lxc/namespace.h
@@ -4,7 +4,7 @@
  * (C) Copyright IBM Corp. 2007, 2009
  *
  * Authors:
- * Daniel Lezcano <dlezcano at fr.ibm.com>
+ * Daniel Lezcano <daniel.lezcano at free.fr>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -18,15 +18,46 @@
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
-#ifndef __namespace_h
-#define __namespace_h
+#ifndef __LXC_NAMESPACE_H
+#define __LXC_NAMESPACE_H
 
-#include <sys/syscall.h>
 #include <sched.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+
+#ifndef CLONE_PARENT_SETTID
+#define CLONE_PARENT_SETTID 0x00100000
+#endif
+
+#ifndef CLONE_CHILD_CLEARTID
+#define CLONE_CHILD_CLEARTID 0x00200000
+#endif
+
+#ifndef CLONE_CHILD_SETTID
+#define CLONE_CHILD_SETTID 0x01000000
+#endif
+
+#ifndef CLONE_VFORK
+#define CLONE_VFORK 0x00004000
+#endif
+
+#ifndef CLONE_THREAD
+#define CLONE_THREAD 0x00010000
+#endif
+
+#ifndef CLONE_SETTLS
+#define CLONE_SETTLS 0x00080000
+#endif
+
+#ifndef CLONE_VM
+#define CLONE_VM 0x00000100
+#endif
 
-#include "config.h"
+#ifndef CLONE_FILES
+#define CLONE_FILES 0x00000400
+#endif
 
 #ifndef CLONE_FS
 #  define CLONE_FS                0x00000200
@@ -34,6 +65,9 @@
 #ifndef CLONE_NEWNS
 #  define CLONE_NEWNS             0x00020000
 #endif
+#ifndef CLONE_NEWCGROUP
+#  define CLONE_NEWCGROUP         0x02000000
+#endif
 #ifndef CLONE_NEWUTS
 #  define CLONE_NEWUTS            0x04000000
 #endif
@@ -49,19 +83,70 @@
 #ifndef CLONE_NEWNET
 #  define CLONE_NEWNET            0x40000000
 #endif
-#ifdef IS_BIONIC
-int clone(int (*fn)(void *), void *child_stack,
-       int flags, void *arg);
+
+enum {
+       LXC_NS_USER,
+       LXC_NS_MNT,
+       LXC_NS_PID,
+       LXC_NS_UTS,
+       LXC_NS_IPC,
+       LXC_NS_NET,
+       LXC_NS_CGROUP,
+       LXC_NS_MAX
+};
+
+extern const struct ns_info {
+       const char *proc_name;
+       int clone_flag;
+       const char *flag_name;
+       const char *env_name;
+} ns_info[LXC_NS_MAX];
+
+#if defined(__ia64__)
+int __clone2(int (*__fn) (void *__arg), void *__child_stack_base,
+             size_t __child_stack_size, int __flags, void *__arg, ...);
 #else
 int clone(int (*fn)(void *), void *child_stack,
        int flags, void *arg, ...
        /* pid_t *ptid, struct user_desc *tls, pid_t *ctid */ );
 #endif
 
-
+/**
+ * lxc_clone() - create a new process
+ *
+ * - allocate stack:
+ *   This function allocates a new stack the size of page and passes it to the
+ *   kernel.
+ *
+ * - support all CLONE_*flags:
+ *   This function supports all CLONE_* flags. If in doubt or not sufficiently
+ *   familiar with process creation in the kernel and interactions with libcs
+ *   this function should be used.
+ *
+ * - pthread_atfork() handlers depending on libc:
+ *   Whether this function runs pthread_atfork() handlers depends on the
+ *   corresponding libc wrapper. glibc currently does not run pthread_atfork()
+ *   handlers but does not guarantee that they are not. Other libcs might or
+ *   might not run pthread_atfork() handlers. If you require guarantees please
+ *   refer to the lxc_raw_clone*() functions in raw_syscalls.{c,h}.
+ *
+ * - should call lxc_raw_getpid():
+ *   The child should use lxc_raw_getpid() to retrieve its pid.
+ */
 extern pid_t lxc_clone(int (*fn)(void *), void *arg, int flags);
 
-extern int lxc_namespace_2_cloneflag(char *namespace);
+extern int lxc_namespace_2_cloneflag(const char *namespace);
+extern int lxc_namespace_2_ns_idx(const char *namespace);
+extern int lxc_namespace_2_std_identifiers(char *namespaces);
 extern int lxc_fill_namespace_flags(char *flaglist, int *flags);
 
+/**
+ * Because of older glibc's pid cache (up to 2.25) whenever clone() is called
+ * the child must must retrieve it's own pid via lxc_raw_getpid().
+ */
+static inline pid_t lxc_raw_getpid(void)
+{
+       return (pid_t) syscall(SYS_getpid);
+}
+
 #endif