HITDAQ/FPGA_nios/hit_pat_bsp/HAL/src/alt_fcntl.c
2024-10-11 14:26:20 +02:00

102 lines
4.5 KiB
C

/******************************************************************************
* *
* License Agreement *
* *
* Copyright (c) 2004 Altera Corporation, San Jose, California, USA. *
* All rights reserved. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the "Software"), *
* to deal in the Software without restriction, including without limitation *
* the rights to use, copy, modify, merge, publish, distribute, sublicense, *
* and/or sell copies of the Software, and to permit persons to whom the *
* Software is furnished to do so, subject to the following conditions: *
* *
* The above copyright notice and this permission notice shall be included in *
* all copies or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR *
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE *
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER *
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *
* DEALINGS IN THE SOFTWARE. *
* *
* This agreement shall be governed in all respects by the laws of the State *
* of California and by the laws of the United States of America. *
* *
* Altera does not recommend, suggest or require that this reference design *
* file be used in conjunction or combination with any other product. *
******************************************************************************/
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdarg.h>
#include "sys/alt_errno.h"
#include "priv/alt_file.h"
#include "alt_types.h"
#include "os/alt_syscall.h"
#define ALT_FCNTL_FLAGS_MASK ((alt_u32) (O_APPEND | O_NONBLOCK))
/*
* fcntl() is a limited implementation of the standard fcntl() system call.
* It can be used to change the state of the flags associated with an open
* file descriptor. Normally these flags are set during the call to
* open(). It is anticipated that the main use of this function will be to
* change the state of a device from blocking to non-blocking (where this is
* supported).
*
* The input argument "fd" is the file descriptor to be manipulated. "cmd"
* is the command to execute. This can be either F_GETFL (return the
* current value of the flags) or F_SETFL (set the value of the flags).
*
* If "cmd" is F_SETFL then the argument "arg" is the new value of flags,
* otherwise "arg" is ignored. Only the flags: O_APPEND and O_NONBLOCK
* can be updated by a call to fcntl(). All other flags remain
* unchanged.
*
* ALT_FCNTL is mapped onto the fcntl() system call in alt_syscall.h
*/
int ALT_FCNTL (int file, int cmd, ...)
{
alt_fd* fd;
long flags;
va_list argp;
/*
* A common error case is that when the file descriptor was created, the call
* to open() failed resulting in a negative file descriptor. This is trapped
* below so that we don't try and process an invalid file descriptor.
*/
fd = (file < 0) ? NULL : &alt_fd_list[file];
if (fd)
{
switch (cmd)
{
case F_GETFL:
return fd->fd_flags & ~((alt_u32) ALT_FD_FLAGS_MASK);
case F_SETFL:
va_start(argp, cmd);
flags = va_arg(argp, long);
fd->fd_flags &= ~ALT_FCNTL_FLAGS_MASK;
fd->fd_flags |= (flags & ALT_FCNTL_FLAGS_MASK);
va_end(argp);
return 0;
default:
ALT_ERRNO = EINVAL;
return -1;
}
}
ALT_ERRNO = EBADFD;
return -1;
}