uclibc-ng/libpthread/linuxthreads/wrapsyscall.c

/* Wrapper around system calls to provide cancellation points.
   Copyright (C) 1996,1997,1998,1999,2000,2001 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   see <http://www.gnu.org/licenses/>.  */

#include <fcntl.h>
#include <sys/mman.h>
#include <pthread.h>
#include <unistd.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdlib.h>
#include <termios.h>
#include <sys/epoll.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/syscall.h>


#ifndef __PIC__
/* We need a hook to force this file to be linked in when static
   libpthread is used.  */
const char __pthread_provide_wrappers = 0;
#endif

/* Using private interface to libc (__libc_foo) to implement
 * cancellable versions of some libc functions */
#define CANCELABLE_SYSCALL(res_type, name, param_list, params)			\
res_type __libc_##name param_list;						\
res_type									\
__attribute__ ((weak))								\
name param_list									\
{										\
  res_type result;								\
  int oldtype;									\
  pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype);		\
  result = __libc_##name params;						\
  pthread_setcanceltype (oldtype, NULL);					\
  return result;								\
}

/* Like CANCELABLE_SYSCALL but the wrapper is a strong definition.  Used for
 * the functions that also export a __GI_ alias (libpthread_hidden_def): a weak
 * wrapper makes that __GI_ symbol weak too, and on MIPS a function derives its
 * PIC gp via %gp_rel(__GI_name) -- with two weak __GI_name (this wrapper and
 * the libc fallback) the linker may pick the fallback, at a different address,
 * so the wrapper computes a wrong gp and SIGSEGVs in its prologue.  A strong
 * wrapper makes its __GI_ win the link, co-located with the code. */
#define CANCELABLE_SYSCALL_STRONG(res_type, name, param_list, params)		\
res_type __libc_##name param_list;						\
res_type									\
name param_list									\
{										\
  res_type result;								\
  int oldtype;									\
  pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype);		\
  result = __libc_##name params;						\
  pthread_setcanceltype (oldtype, NULL);					\
  return result;								\
}

#define CANCELABLE_SYSCALL_VA(res_type, name, param_list, params, last_arg)	\
res_type __libc_##name param_list;						\
res_type									\
__attribute__ ((weak))								\
name param_list									\
{										\
  res_type result;								\
  int oldtype;									\
  va_list ap;									\
  pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype);		\
  va_start (ap, last_arg);							\
  result = __libc_##name params;						\
  va_end (ap);									\
  pthread_setcanceltype (oldtype, NULL);					\
  return result;								\
}


/* close(2).  */
CANCELABLE_SYSCALL (int, close, (int fd), (fd))


/* fcntl(2).  */
CANCELABLE_SYSCALL_VA (int, fcntl, (int fd, int cmd, ...),
		       (fd, cmd, va_arg (ap, long int)), cmd)

#if __WORDSIZE == 32
/* fcntl64(2).  */
CANCELABLE_SYSCALL_VA (int, fcntl64, (int fd, int cmd, ...),
		       (fd, cmd, va_arg (ap, long int)), cmd)
#endif

/* fsync(2).  */
CANCELABLE_SYSCALL (int, fsync, (int fd), (fd))


/* lseek(2).  */
CANCELABLE_SYSCALL (off_t, lseek, (int fd, off_t offset, int whence),
		    (fd, offset, whence))

/* lseek64(2).  */
CANCELABLE_SYSCALL (off64_t, lseek64, (int fd, off64_t offset, int whence),
		    (fd, offset, whence))

#if defined(__NR_msync) && defined(__ARCH_USE_MMU__)

/* msync(2).  */
CANCELABLE_SYSCALL (int, msync, (void *addr, size_t length, int flags),
		    (addr, length, flags))
#endif


/* nanosleep(2).  */
libpthread_hidden_proto(nanosleep)
CANCELABLE_SYSCALL_STRONG (int, nanosleep, (const struct timespec *requested_time,
				     struct timespec *remaining),
		    (requested_time, remaining))
libpthread_hidden_def(nanosleep)


/* open(2).  */
CANCELABLE_SYSCALL_VA (int, open, (const char *pathname, int flags, ...),
		       (pathname, flags, va_arg (ap, mode_t)), flags)


/* open64(3).  */
CANCELABLE_SYSCALL_VA (int, open64, (const char *pathname, int flags, ...),
		       (pathname, flags, va_arg (ap, mode_t)), flags)

/* pause(2).  */
CANCELABLE_SYSCALL (int, pause, (void), ())


/* Enable this if enabling these in syscalls.c */
/* pread(3).  */
CANCELABLE_SYSCALL (ssize_t, pread, (int fd, void *buf, size_t count,
				     off_t offset),
		    (fd, buf, count, offset))


#if defined __NR_pread64
/* pread64(3).  */
CANCELABLE_SYSCALL (ssize_t, pread64, (int fd, void *buf, size_t count,
				       off64_t offset),
		    (fd, buf, count, offset))
#endif

/* pwrite(3).  */
CANCELABLE_SYSCALL (ssize_t, pwrite, (int fd, const void *buf, size_t n,
				      off_t offset),
		    (fd, buf, n, offset))


#if defined __NR_pwrited64
/* pwrite64(3).  */
CANCELABLE_SYSCALL (ssize_t, pwrite64, (int fd, const void *buf, size_t n,
					off64_t offset),
		    (fd, buf, n, offset))
#endif

/* read(2).  */
CANCELABLE_SYSCALL (ssize_t, read, (int fd, void *buf, size_t count),
		    (fd, buf, count))


/* system(3).  */
CANCELABLE_SYSCALL (int, system, (const char *line), (line))


/* tcdrain(2).  */
CANCELABLE_SYSCALL (int, tcdrain, (int fd), (fd))


/* wait(2).  */
CANCELABLE_SYSCALL (__pid_t, wait, (__WAIT_STATUS_DEFN stat_loc), (stat_loc))


/* waitpid(2).  */
libpthread_hidden_proto(waitpid)
CANCELABLE_SYSCALL_STRONG (__pid_t, waitpid, (__pid_t pid, int *stat_loc,
				       int options),
		    (pid, stat_loc, options))
libpthread_hidden_def(waitpid)


/* write(2).  */
CANCELABLE_SYSCALL (ssize_t, write, (int fd, const void *buf, size_t n),
		    (fd, buf, n))

#if defined __UCLIBC_HAS_SOCKET__
/* The following system calls are thread cancellation points specified
   in XNS.  */

/* accept(2).  */
CANCELABLE_SYSCALL (int, accept, (int fd, __SOCKADDR_ARG addr,
				  socklen_t *addr_len),
		    (fd, addr, addr_len))

#if defined __UCLIBC_LINUX_SPECIFIC__
/* accept4(2).  */
CANCELABLE_SYSCALL (int, accept4, (int fd, __SOCKADDR_ARG addr,
				  socklen_t *addr_len, int flags),
		    (fd, addr, addr_len, flags))
#endif

/* connect(2).  */
CANCELABLE_SYSCALL (int, connect, (int fd, __CONST_SOCKADDR_ARG addr,
				     socklen_t len),
		    (fd, addr, len))

/* recv(2).  */
CANCELABLE_SYSCALL (ssize_t, recv, (int fd, __ptr_t buf, size_t n, int flags),
		    (fd, buf, n, flags))

/* recvfrom(2).  */
CANCELABLE_SYSCALL (ssize_t, recvfrom, (int fd, __ptr_t buf, size_t n, int flags,
					__SOCKADDR_ARG addr, socklen_t *addr_len),
		    (fd, buf, n, flags, addr, addr_len))

/* recvmsg(2).  */
CANCELABLE_SYSCALL (ssize_t, recvmsg, (int fd, struct msghdr *message, int flags),
		    (fd, message, flags))

/* send(2).  */
CANCELABLE_SYSCALL (ssize_t, send, (int fd, const __ptr_t buf, size_t n,
				    int flags),
		    (fd, buf, n, flags))

/* sendmsg(2).  */
CANCELABLE_SYSCALL (ssize_t, sendmsg, (int fd, const struct msghdr *message,
				       int flags),
		    (fd, message, flags))

/* sendto(2).  */
CANCELABLE_SYSCALL (ssize_t, sendto, (int fd, const __ptr_t buf, size_t n,
				      int flags, __CONST_SOCKADDR_ARG addr,
				      socklen_t addr_len),
		    (fd, buf, n, flags, addr, addr_len))
#endif /* __UCLIBC_HAS_SOCKET__ */

#ifdef  __UCLIBC_HAS_EPOLL__
# include <sys/epoll.h>
# ifdef __NR_epoll_wait
CANCELABLE_SYSCALL (int, epoll_wait, (int epfd, struct epoll_event *events, int maxevents, int timeout),
		    (epfd, events, maxevents, timeout))
# endif
# ifdef __NR_epoll_pwait
CANCELABLE_SYSCALL (int, epoll_pwait, (int epfd, struct epoll_event *events, int maxevents, int timeout,
				       const sigset_t *set),
		    (epfd, events, maxevents, timeout, set))
# endif
#endif