newlib-cygwin/newlib/libc/sys/linux/fpathconf.c

306 lines
6.1 KiB
C

/* Linux specific extensions to fpathconf.
Copyright (C) 1991,95,96,98,99,2000,2001 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. */
/* Modified for newlib July 19, 2002 by Jeff Johnston */
#include <errno.h>
#include <stddef.h>
#include <unistd.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>
#include <machine/weakalias.h>
#include "linux_fsinfo.h"
#define __set_errno(x) errno=(x)
/* The Linux kernel header mentioned this as a kind of generic value. */
#define LINUX_LINK_MAX 127
static long int posix_fpathconf (int fd, int name);
/* Get file-specific information about descriptor FD. */
long int
__fpathconf (fd, name)
int fd;
int name;
{
if (name == _PC_LINK_MAX)
{
struct statfs fsbuf;
/* Determine the filesystem type. */
if (__fstatfs (fd, &fsbuf) < 0)
{
if (errno == ENOSYS)
/* not possible, return the default value. */
return LINUX_LINK_MAX;
/* Some error occured. */
return -1;
}
switch (fsbuf.f_type)
{
case EXT2_SUPER_MAGIC:
return EXT2_LINK_MAX;
case MINIX_SUPER_MAGIC:
case MINIX_SUPER_MAGIC2:
return MINIX_LINK_MAX;
case MINIX2_SUPER_MAGIC:
case MINIX2_SUPER_MAGIC2:
return MINIX2_LINK_MAX;
case XENIX_SUPER_MAGIC:
return XENIX_LINK_MAX;
case SYSV4_SUPER_MAGIC:
case SYSV2_SUPER_MAGIC:
return SYSV_LINK_MAX;
case COH_SUPER_MAGIC:
return COH_LINK_MAX;
case UFS_MAGIC:
case UFS_CIGAM:
return UFS_LINK_MAX;
case REISERFS_SUPER_MAGIC:
return REISERFS_LINK_MAX;
default:
return LINUX_LINK_MAX;
}
}
return posix_fpathconf (fd, name);
}
/* Get file-specific information about descriptor FD. */
static long int
posix_fpathconf (fd, name)
int fd;
int name;
{
if (fd < 0)
{
__set_errno (EBADF);
return -1;
}
switch (name)
{
default:
__set_errno (EINVAL);
return -1;
case _PC_LINK_MAX:
#ifdef LINK_MAX
return LINK_MAX;
#else
return -1;
#endif
case _PC_MAX_CANON:
#ifdef MAX_CANON
return MAX_CANON;
#else
return -1;
#endif
case _PC_MAX_INPUT:
#ifdef MAX_INPUT
return MAX_INPUT;
#else
return -1;
#endif
case _PC_NAME_MAX:
#ifdef NAME_MAX
{
struct statfs buf;
int save_errno = errno;
if (__fstatfs (fd, &buf) < 0)
{
if (errno == ENOSYS)
{
__set_errno (save_errno);
return NAME_MAX;
}
else if (errno == ENODEV)
__set_errno (EINVAL);
return -1;
}
else
{
#ifdef _STATFS_F_NAMELEN
return buf.f_namelen;
#else
# ifdef _STATFS_F_NAME_MAX
return buf.f_name_max;
# else
return NAME_MAX;
# endif
#endif
}
}
#else
return -1;
#endif
case _PC_PATH_MAX:
#ifdef PATH_MAX
return PATH_MAX;
#else
return -1;
#endif
case _PC_PIPE_BUF:
#ifdef PIPE_BUF
return PIPE_BUF;
#else
return -1;
#endif
case _PC_CHOWN_RESTRICTED:
#ifdef _POSIX_CHOWN_RESTRICTED
return _POSIX_CHOWN_RESTRICTED;
#else
return -1;
#endif
case _PC_NO_TRUNC:
#ifdef _POSIX_NO_TRUNC
return _POSIX_NO_TRUNC;
#else
return -1;
#endif
case _PC_VDISABLE:
#ifdef _POSIX_VDISABLE
return _POSIX_VDISABLE;
#else
return -1;
#endif
case _PC_SYNC_IO:
#ifdef _POSIX_SYNC_IO
return _POSIX_SYNC_IO;
#else
return -1;
#endif
case _PC_ASYNC_IO:
#ifdef _POSIX_ASYNC_IO
{
/* AIO is only allowed on regular files and block devices. */
struct stat64 st;
if (__fxstat64 (_STAT_VER, fd, &st) < 0
|| (! S_ISREG (st.st_mode) && ! S_ISBLK (st.st_mode)))
return -1;
else
return 1;
}
#else
return -1;
#endif
case _PC_PRIO_IO:
#ifdef _POSIX_PRIO_IO
return _POSIX_PRIO_IO;
#else
return -1;
#endif
case _PC_SOCK_MAXBUF:
#ifdef SOCK_MAXBUF
return SOCK_MAXBUF;
#else
return -1;
#endif
case _PC_FILESIZEBITS:
#ifdef FILESIZEBITS
return FILESIZEBITS;
#else
/* We let platforms with larger file sizes overwrite this value. */
return 32;
#endif
case _PC_REC_INCR_XFER_SIZE:
/* XXX It is not entirely clear what the limit is supposed to do.
What is incremented? */
return -1;
case _PC_REC_MAX_XFER_SIZE:
/* XXX It is not entirely clear what the limit is supposed to do.
In general there is no top limit of the number of bytes which
case be transported at once. */
return -1;
case _PC_REC_MIN_XFER_SIZE:
{
/* XXX It is not entirely clear what the limit is supposed to do.
I assume this is the block size of the filesystem. */
struct statvfs64 sv;
if (__fstatvfs64 (fd, &sv) < 0)
return -1;
return sv.f_bsize;
}
case _PC_REC_XFER_ALIGN:
{
/* XXX It is not entirely clear what the limit is supposed to do.
I assume that the number should reflect the minimal block
alignment. */
struct statvfs64 sv;
if (__fstatvfs64 (fd, &sv) < 0)
return -1;
return sv.f_frsize;
}
case _PC_ALLOC_SIZE_MIN:
{
/* XXX It is not entirely clear what the limit is supposed to do.
I assume that the number should reflect the minimal block
alignment. */
struct statvfs64 sv;
if (__fstatvfs64 (fd, &sv) < 0)
return -1;
return sv.f_frsize;
}
case _PC_SYMLINK_MAX:
/* In general there are no limits. If a system has one it should
overwrite this case. */
return -1;
}
}
weak_alias (__fpathconf, fpathconf)