mirror of
https://github.com/marqs85/ossc
synced 2025-11-01 08:26:03 +03:00
126 lines
4.5 KiB
C
126 lines
4.5 KiB
C
/******************************************************************************
|
|
* *
|
|
* License Agreement *
|
|
* *
|
|
* Copyright (c) 2006 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 "sys/alt_errno.h"
|
|
#include "sys/alt_warning.h"
|
|
#include "priv/alt_file.h"
|
|
#include "os/alt_syscall.h"
|
|
|
|
/*
|
|
* The read() system call is used to read a block of data from a file or device.
|
|
* This function simply vectors the request to the device driver associated
|
|
* with the input file descriptor "file".
|
|
*
|
|
* ALT_READ is mapped onto the read() system call in alt_syscall.h
|
|
*/
|
|
|
|
#ifdef ALT_USE_DIRECT_DRIVERS
|
|
|
|
#include "system.h"
|
|
#include "sys/alt_driver.h"
|
|
|
|
/*
|
|
* Provide minimal version that just reads from the stdin device when provided.
|
|
*/
|
|
|
|
int ALT_READ (int file, void *ptr, size_t len)
|
|
{
|
|
#ifdef ALT_STDIN_PRESENT
|
|
ALT_DRIVER_READ_EXTERNS(ALT_STDIN_DEV);
|
|
#endif
|
|
|
|
#if !defined(ALT_STDIN_PRESENT)
|
|
/* Generate a link time warning, should this function ever be called. */
|
|
ALT_STUB_WARNING(read);
|
|
#endif
|
|
|
|
switch (file) {
|
|
#ifdef ALT_STDIN_PRESENT
|
|
case 0: /* stdin file descriptor */
|
|
return ALT_DRIVER_READ(ALT_STDIN_DEV, ptr, len, 0);
|
|
#endif /* ALT_STDIN_PRESENT */
|
|
default:
|
|
ALT_ERRNO = EBADFD;
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
#else /* !ALT_USE_DIRECT_DRIVERS */
|
|
|
|
int ALT_READ (int file, void *ptr, size_t len)
|
|
{
|
|
alt_fd* fd;
|
|
int rval;
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
/*
|
|
* If the file has not been opened with read access, or if the driver does
|
|
* not provide an implementation of read(), generate an error. Otherwise
|
|
* call the drivers read() function to process the request.
|
|
*/
|
|
|
|
if (((fd->fd_flags & O_ACCMODE) != O_WRONLY) &&
|
|
(fd->dev->read))
|
|
{
|
|
if ((rval = fd->dev->read(fd, ptr, len)) < 0)
|
|
{
|
|
ALT_ERRNO = -rval;
|
|
return -1;
|
|
}
|
|
return rval;
|
|
}
|
|
else
|
|
{
|
|
ALT_ERRNO = EACCES;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
ALT_ERRNO = EBADFD;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
#endif /* ALT_USE_DIRECT_DRIVERS */
|