nuttx/libs/libc/misc/lib_ioctl.c
Gregory Nutt a64869aa67 CONFIG_NFILE_DESCRIPTORS=0 can no longer be used to disable the file system. NuttX with no file system does not make sense.
Squashed commit of the following:

    configs/:  The few configurations that formerly set CONFIG_NFILE_DESCRIPTORS=0 should not default, rather they should set the number of descriptors to 3.
    fs/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    tools/:  Tools updates for changes to usage of CONFIG_NFILE_DESCRIPTORS.
    syscall/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    libs/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    include/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    drivers/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    Documentation/:  Remove all references to CONFIG_NFILE_DESCRIPTORS == 0
    binfmt/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    arch/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    net/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    sched/:  Remove all conditional logic based on CONFIG_NFILE_DESCRIPTORS == 0
    sched/Kconfig:  CONFIG_NFILE_DESCRIPTORS may no longer to set to a value less than 3
    configs/:  Remove all settings for CONFIG_NFILE_DESCRIPTORS < 3
2019-02-11 12:09:26 -06:00

118 lines
4.2 KiB
C

/****************************************************************************
* libs/libc/misc/lib_ioctl.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdarg.h>
#include <errno.h>
#include <assert.h>
#include <nuttx/fs/fs.h>
#include "libc.h"
#ifdef CONFIG_LIBC_IOCTL_VARIADIC
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ioctl
*
* Description:
* Perform device specific operations.
*
* Input Parameters:
* fd File/socket descriptor of device
* req The ioctl command
* ... A third argument of type unsigned long is expected
*
* Returned Value:
* >=0 on success (positive non-zero values are cmd-specific)
* -1 on failure with errno set properly:
*
* EBADF
* 'fd' is not a valid descriptor.
* EFAULT
* 'arg' references an inaccessible memory area.
* EINVAL
* 'cmd' or 'arg' is not valid.
* ENOTTY
* 'fd' is not associated with a character special device.
* ENOTTY
* The specified request does not apply to the kind of object that the
* descriptor 'fd' references.
*
****************************************************************************/
int ioctl(int fd, int req, ...)
{
unsigned long arg;
va_list ap;
/* Get the unsigned long argument.
*
* REVISIT: This could be the cause of the crash down the road if the
* actual size of the argument is anything other than sizeof(unsigned long).
* Most small integers will be promoted to 'int'. ARM should pass the
* following test with all three types having sizeof(type) == 4 bytes.
* 'float' should also be tested. But 'long long' and 'double' are out of
* the question! Don't try to pass them.
*
* And what will happen if no third argument is passed? In most cases,
* this should just result in a garbage value for arg. But you may
* discover cases where something worse happens!
*/
DEBUGASSERT(sizeof(int) == sizeof(unsigned long) &&
sizeof(FAR void *) == sizeof(unsigned long));
va_start(ap, req);
arg = va_arg(ap, unsigned long);
va_end(ap);
/* Then let fs_ioctl() to the real work */
return fs_ioctl(fd, req, arg);
}
#endif /* CONFIG_LIBC_IOCTL_VARIADIC */