Hurd: dup3

This commit is contained in:
Thomas Schwinge 2012-05-10 13:15:40 -07:00 committed by Roland McGrath
parent cd9fa98583
commit 5aa3a74a59
5 changed files with 163 additions and 117 deletions

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@ -1,3 +1,12 @@
2012-05-10 Thomas Schwinge <thomas@schwinge.name>
dup3 for GNU Hurd.
* include/unistd.h: Declare __dup3 and use libc_hidden_proto on it.
* sysdeps/mach/hurd/dup3.c: New file, copy from dup2.c. Evolve it to
implement dup3 and do some further code clean-ups.
* sysdeps/mach/hurd/dup2.c (__dup2): Reimplement using __dup3.
* sysdeps/mach/hurd/kernel-features.h (__ASSUME_DUP3): Define.
2012-05-10 Samuel Thibault <samuel.thibault@ens-lyon.org>
* sysdeps/mach/hurd/dl-sysdep.c: Conditionalize contents on [SHARED].

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@ -80,7 +80,8 @@ char *__canonicalize_directory_name_internal (const char *__thisdir,
extern int __dup (int __fd);
extern int __dup2 (int __fd, int __fd2);
libc_hidden_proto (__dup2)
libc_hidden_proto (dup3)
extern int __dup3 (int __fd, int __fd2, int flags);
libc_hidden_proto (__dup3)
extern int __execve (const char *__path, char *const __argv[],
char *const __envp[]);
extern long int __pathconf (const char *__path, int __name);

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@ -1,4 +1,5 @@
/* Copyright (C) 1991, 92, 93, 94, 95, 97, 2002 Free Software Foundation, Inc.
/* Copyright (C) 1991-2012 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
@ -15,119 +16,20 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <hurd.h>
#include <hurd/fd.h>
/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
open on the same file as FD is. Return FD2 or -1. */
int
__dup2 (fd, fd2)
int fd;
int fd2;
__dup2 (int fd, int fd2)
{
struct hurd_fd *d;
int flags = 0;
/* Extract the ports and flags from FD. */
d = _hurd_fd_get (fd);
if (d == NULL)
{
errno = EBADF;
return -1;
}
if (fd2 == fd)
/* See the comment in dup3. */
flags = -1;
HURD_CRITICAL_BEGIN;
__spin_lock (&d->port.lock);
if (d->port.port == MACH_PORT_NULL)
{
__spin_unlock (&d->port.lock);
errno = EBADF;
fd2 = -1;
}
else if (fd2 == fd)
/* FD is valid and FD2 is already the same; just return it. */
__spin_unlock (&d->port.lock);
else
{
struct hurd_userlink ulink, ctty_ulink;
int flags = d->flags;
io_t ctty = _hurd_port_get (&d->ctty, &ctty_ulink);
io_t port = _hurd_port_locked_get (&d->port, &ulink); /* Unlocks D. */
if (fd2 < 0)
{
errno = EBADF;
fd2 = -1;
}
else
{
/* Get a hold of the destination descriptor. */
struct hurd_fd *d2;
if (fd2 >= _hurd_dtablesize)
{
/* The table is not large enough to hold the destination
descriptor. Enlarge it as necessary to allocate this
descriptor. */
__mutex_unlock (&_hurd_dtable_lock);
/* We still hold FD1's lock, but this is safe because
_hurd_alloc_fd will only examine the cells starting
at FD2. */
d2 = _hurd_alloc_fd (NULL, fd2);
if (d2)
__spin_unlock (&d2->port.lock);
__mutex_lock (&_hurd_dtable_lock);
}
else
{
d2 = _hurd_dtable[fd2];
if (d2 == NULL)
{
/* Must allocate a new one. We don't initialize the port
cells with this call so that if it fails (out of
memory), we will not have already added user
references for the ports, which we would then have to
deallocate. */
d2 = _hurd_dtable[fd2] = _hurd_new_fd (MACH_PORT_NULL,
MACH_PORT_NULL);
}
}
if (d2 == NULL)
{
fd2 = -1;
if (errno == EINVAL)
errno = EBADF; /* POSIX.1-1990 6.2.1.2 ll 54-55. */
}
else
{
/* Give the ports each a user ref for the new descriptor. */
__mach_port_mod_refs (__mach_task_self (), port,
MACH_PORT_RIGHT_SEND, 1);
if (ctty != MACH_PORT_NULL)
__mach_port_mod_refs (__mach_task_self (), ctty,
MACH_PORT_RIGHT_SEND, 1);
/* Install the ports and flags in the new descriptor slot. */
__spin_lock (&d2->port.lock);
d2->flags = flags & ~FD_CLOEXEC; /* Dup clears FD_CLOEXEC. */
_hurd_port_set (&d2->ctty, ctty);
_hurd_port_locked_set (&d2->port, port); /* Unlocks D2. */
}
}
__mutex_unlock (&_hurd_dtable_lock);
_hurd_port_free (&d->port, &ulink, port);
if (ctty != MACH_PORT_NULL)
_hurd_port_free (&d->ctty, &ctty_ulink, port);
}
HURD_CRITICAL_END;
return fd2;
return __dup3 (fd, fd2, flags);
}
libc_hidden_def (__dup2)
weak_alias (__dup2, dup2)

141
sysdeps/mach/hurd/dup3.c Normal file
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@ -0,0 +1,141 @@
/* Duplicate a file descriptor to a given number, with flags. Hurd version.
Copyright (C) 1991-2012 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <hurd.h>
#include <hurd/fd.h>
/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
open on the same file as FD is, and setting FD2's flags according to FLAGS.
Return FD2 or -1. */
int
__dup3 (int fd, int fd2, int flags)
{
struct hurd_fd *d;
/* Both passing flags different from O_CLOEXEC and FD2 being the same as FD
are invalid. */
if ((flags & ~O_CLOEXEC
|| fd2 == fd)
/* ... with the exception in case that dup2 behavior is requested: if FD
is valid and FD2 is already the same then just return it. */
&& ! (flags == -1
&& fd2 == fd))
return __hurd_fail (EINVAL);
/* Extract the ports and flags from FD. */
d = _hurd_fd_get (fd);
if (d == NULL)
return __hurd_fail (EBADF);
HURD_CRITICAL_BEGIN;
__spin_lock (&d->port.lock);
if (d->port.port == MACH_PORT_NULL)
{
__spin_unlock (&d->port.lock);
fd2 = __hurd_fail (EBADF);
}
else if (fd2 == fd)
__spin_unlock (&d->port.lock);
else
{
struct hurd_userlink ulink, ctty_ulink;
int d_flags = d->flags;
io_t ctty = _hurd_port_get (&d->ctty, &ctty_ulink);
io_t port = _hurd_port_locked_get (&d->port, &ulink); /* Unlocks D. */
if (fd2 < 0)
fd2 = __hurd_fail (EBADF);
else
{
/* Get a hold of the destination descriptor. */
struct hurd_fd *d2;
if (fd2 >= _hurd_dtablesize)
{
/* The table is not large enough to hold the destination
descriptor. Enlarge it as necessary to allocate this
descriptor. */
__mutex_unlock (&_hurd_dtable_lock);
/* We still hold FD1's lock, but this is safe because
_hurd_alloc_fd will only examine the cells starting
at FD2. */
d2 = _hurd_alloc_fd (NULL, fd2);
if (d2)
__spin_unlock (&d2->port.lock);
__mutex_lock (&_hurd_dtable_lock);
}
else
{
d2 = _hurd_dtable[fd2];
if (d2 == NULL)
{
/* Must allocate a new one. We don't initialize the port
cells with this call so that if it fails (out of
memory), we will not have already added user
references for the ports, which we would then have to
deallocate. */
d2 = _hurd_dtable[fd2] = _hurd_new_fd (MACH_PORT_NULL,
MACH_PORT_NULL);
}
}
if (d2 == NULL)
{
fd2 = -1;
if (errno == EINVAL)
errno = EBADF; /* POSIX.1-1990 6.2.1.2 ll 54-55. */
}
else
{
/* Give the ports each a user ref for the new descriptor. */
__mach_port_mod_refs (__mach_task_self (), port,
MACH_PORT_RIGHT_SEND, 1);
if (ctty != MACH_PORT_NULL)
__mach_port_mod_refs (__mach_task_self (), ctty,
MACH_PORT_RIGHT_SEND, 1);
/* Install the ports and flags in the new descriptor slot. */
__spin_lock (&d2->port.lock);
if (flags & O_CLOEXEC)
d2->flags = d_flags | FD_CLOEXEC;
else
/* dup clears FD_CLOEXEC. */
d2->flags = d_flags & ~FD_CLOEXEC;
_hurd_port_set (&d2->ctty, ctty);
_hurd_port_locked_set (&d2->port, port); /* Unlocks D2. */
}
}
__mutex_unlock (&_hurd_dtable_lock);
_hurd_port_free (&d->port, &ulink, port);
if (ctty != MACH_PORT_NULL)
_hurd_port_free (&d->ctty, &ctty_ulink, port);
}
HURD_CRITICAL_END;
return fd2;
}
libc_hidden_def (__dup3)
weak_alias (__dup3, dup3)

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@ -1,5 +1,5 @@
/* Set flags signalling availability of certain operating system features.
Copyright (C) 2007-2012 Free Software Foundation, Inc.
Copyright (C) 2012 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
@ -20,13 +20,6 @@
Almost none of these are used outside of sysdeps/unix/sysv/linux code.
But those referring to POSIX-level features like O_* flags can be. */
#include <fcntl.h>
/* If a system defines the O_CLOEXEC constant but it is sometimes ignored,
it must override this file to define __ASSUME_O_CLOEXEC conditionally
(or not at all) to indicate when O_CLOEXEC actually works. */
#ifdef O_CLOEXEC
# define __ASSUME_O_CLOEXEC 1
#endif
#define __ASSUME_O_CLOEXEC 1
#define __ASSUME_DUP3 1
#define __ASSUME_ACCEPT4 1