125 lines
2.9 KiB
C++
125 lines
2.9 KiB
C++
/* fcntl.cc: fcntl syscall
|
|
|
|
This file is part of Cygwin.
|
|
|
|
This software is a copyrighted work licensed under the terms of the
|
|
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
|
|
details. */
|
|
|
|
#include "winsup.h"
|
|
#include <unistd.h>
|
|
#include "cygerrno.h"
|
|
#include "security.h"
|
|
#include "path.h"
|
|
#include "fhandler.h"
|
|
#include "dtable.h"
|
|
#include "cygheap.h"
|
|
#include "cygtls.h"
|
|
|
|
extern "C" int
|
|
fcntl64 (int fd, int cmd, ...)
|
|
{
|
|
int res = -1;
|
|
intptr_t arg = 0;
|
|
va_list args;
|
|
|
|
pthread_testcancel ();
|
|
|
|
__try
|
|
{
|
|
|
|
debug_printf ("fcntl(%d, %d, ...)", fd, cmd);
|
|
|
|
/* Don't lock the fd table when performing locking calls. */
|
|
cygheap_fdget cfd (fd, cmd < F_GETLK || cmd > F_SETLKW);
|
|
if (cfd < 0)
|
|
__leave;
|
|
|
|
/* FIXME? All numerical args to fcntl are defined as long on Linux.
|
|
This relies on a really dirty trick on x86_64: A 32 bit mov to
|
|
a register (e.g. mov $1, %edx) always sets the high 32 bit to 0.
|
|
We're following the Linux lead here since the third arg to any
|
|
function is in a register anyway (%r8 in MS ABI). That's the easy
|
|
case which is covered here by always reading the arg with
|
|
sizeof (intptr_t) == sizeof (long) == sizeof (void*) which matches
|
|
all targets.
|
|
|
|
However, the POSIX standard defines all numerical args as type int.
|
|
If we take that literally, we had a (small) problem on 64 bit, since
|
|
sizeof (void*) != sizeof (int). If we would like to follow POSIX more
|
|
closely than Linux, we'd have to call va_arg on a per cmd basis. */
|
|
|
|
va_start (args, cmd);
|
|
arg = va_arg (args, intptr_t);
|
|
va_end (args);
|
|
|
|
switch (cmd)
|
|
{
|
|
case F_DUPFD:
|
|
case F_DUPFD_CLOEXEC:
|
|
if (arg >= 0 && arg < OPEN_MAX)
|
|
{
|
|
int flags = cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0;
|
|
res = cygheap->fdtab.dup3 (fd, cygheap_fdnew ((arg) - 1), flags);
|
|
}
|
|
else
|
|
{
|
|
set_errno (EINVAL);
|
|
res = -1;
|
|
}
|
|
break;
|
|
default:
|
|
res = cfd->fcntl (cmd, arg);
|
|
break;
|
|
}
|
|
}
|
|
__except (EFAULT) {}
|
|
__endtry
|
|
syscall_printf ("%R = fcntl(%d, %d, %ly)", res, fd, cmd, arg);
|
|
return res;
|
|
}
|
|
|
|
#ifdef __i386__
|
|
extern "C" int
|
|
_fcntl (int fd, int cmd, ...)
|
|
{
|
|
intptr_t arg = 0;
|
|
va_list args;
|
|
struct __flock32 *src = NULL;
|
|
struct flock dst;
|
|
|
|
__try
|
|
{
|
|
va_start (args, cmd);
|
|
arg = va_arg (args, intptr_t);
|
|
va_end (args);
|
|
if (cmd == F_GETLK || cmd == F_SETLK || cmd == F_SETLKW)
|
|
{
|
|
src = (struct __flock32 *) arg;
|
|
dst.l_type = src->l_type;
|
|
dst.l_whence = src->l_whence;
|
|
dst.l_start = src->l_start;
|
|
dst.l_len = src->l_len;
|
|
dst.l_pid = src->l_pid;
|
|
arg = (intptr_t) &dst;
|
|
}
|
|
int res = fcntl64 (fd, cmd, arg);
|
|
if (cmd == F_GETLK)
|
|
{
|
|
src->l_type = dst.l_type;
|
|
src->l_whence = dst.l_whence;
|
|
src->l_start = dst.l_start;
|
|
src->l_len = dst.l_len;
|
|
src->l_pid = (short) dst.l_pid;
|
|
}
|
|
return res;
|
|
}
|
|
__except (EFAULT)
|
|
__endtry
|
|
return -1;
|
|
}
|
|
#else
|
|
EXPORT_ALIAS (fcntl64, fcntl)
|
|
EXPORT_ALIAS (fcntl64, _fcntl)
|
|
#endif
|