include/clone_internal.h

   1 #ifndef _CLONE_INTERNAL_H
   2 #define _CLONE_INTERNAL_H
   3
   4 #include <clone3.h>
   5
   6 /* The clone3 syscall provides a superset of the functionality of the clone
   7    interface.  The kernel might extend __CL_ARGS struct in the future, with
   8    each version with a different __SIZE.  If the child is created, it will
   9    start __FUNC function with __ARG arguments.
  10
  11    Different than kernel, the implementation also returns EINVAL for an
  12    invalid NULL __CL_ARGS or __FUNC (similar to __clone).
  13
  14    All callers are responsible for correctly aligning the stack.  The stack is
  15    not aligned prior to the syscall (this differs from the exported __clone).
  16
  17    This function is only implemented if the ABI defines HAVE_CLONE3_WRAPPER.
  18 */
  19 extern int __clone3 (struct clone_args *__cl_args, size_t __size,
  20                      int (*__func) (void *__arg), void *__arg);
  21
  22 /* The internal wrapper of clone/clone2 and clone3.  Different than __clone3,
  23    it will align the stack if required.  If __clone3 returns -1 with ENOSYS,
  24    fall back to clone or clone2.  */
  25 extern int __clone_internal (struct clone_args *__cl_args,
  26                              int (*__func) (void *__arg), void *__arg);
  27 /* clone3 wrapper with a sticky check to avoid re-issuing the syscall if
  28    it fails with ENOSYS.  */
  29 extern int __clone3_internal (struct clone_args *cl_args,
  30                               int (*func) (void *args), void *arg)
  31      attribute_hidden;
  32 /* The fallback code which calls clone/clone2 based on clone3 arguments.  */
  33 extern int __clone_internal_fallback (struct clone_args *__cl_args,
  34                                       int (*__func) (void *__arg),
  35                                       void *__arg)
  36      attribute_hidden;
  37
  38 /* Return whether the kernel supports pid file descriptor, including clone
  39    with CLONE_PIDFD and waitid with P_PIDFD.  */
  40 extern bool __clone_pidfd_supported (void) attribute_hidden;
  41
  42 #ifndef _ISOMAC
  43 libc_hidden_proto (__clone3)
  44 libc_hidden_proto (__clone_internal)
  45 #endif
  46
  47 #endif