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#ifndef __ALT_FILE_H__

#define __ALT_FILE_H__

/******************************************************************************

*                                                                             *

* 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.          *

******************************************************************************/

/******************************************************************************

*                                                                             *

* THIS IS A LIBRARY READ-ONLY SOURCE FILE. DO NOT EDIT.                       *

*                                                                             *

******************************************************************************/

#include "sys/alt_dev.h"

#include "sys/alt_llist.h"

#include "os/alt_sem.h"

#include "alt_types.h"

/*

 * This header provides the internal defenitions required to control file

 * access. These variables and functions are not guaranteed to exist in

 * future implementations of the HAL.

 */

#ifdef __cplusplus

extern "C"

{

#endif /* __cplusplus */

/*

 * The function alt_find_dev() is used to search the device list "list" to

 * locate a device named "name". If a match is found, then a pointer to the

 * device is returned, otherwise NULL is returned.

 */

extern alt_dev* alt_find_dev (const char* name, alt_llist* list);

/*

 * alt_find_file() is used to search the list of registered file systems to

 * find the filesystem that the file named "name" belongs to. If a match is

 * found, then a pointer to the filesystems alt_dev structure is returned,

 * otherwise NULL is returned.

 *

 * Note that a match does not indicate that the file exists, only that a

 * filesystem exists that is registered for a partition that could contain

 * the file. The filesystems open() function would need to be called in order

 * to determine if the file exists.

 */

extern alt_dev* alt_find_file (const char* name);

/*

 * alt_get_fd() is used to allocate a file descriptor for the device or

 * filesystem "dev". A negative return value indicates an error, otherwise the

 * return value is the index of the file descriptor within the file descriptor

 * pool.

 */

extern int alt_get_fd (alt_dev* dev);

/*

 * alt_release_fd() is called to free the file descriptor with index "fd".

 */

extern void alt_release_fd (int fd);

/*

 * alt_fd_lock() is called by ioctl() to mark the file descriptor "fd" as

 * being open for exclusive access. Subsequent calls to open() for the device

 * associated with "fd" will fail. A device is unlocked by either calling

 * close() for "fd", or by an alternate call to ioctl() (see ioctl.c for

 * details).

 */

extern int alt_fd_lock (alt_fd* fd);

/*

 * alt_fd_unlock() is called by ioctl() to unlock a descriptor previously

 * locked by a call to alt_fd_lock().

 */

extern int alt_fd_unlock (alt_fd* fd);

/*

 * "alt_fd_list" is the pool of file descriptors.

 */

extern alt_fd alt_fd_list[];

/*

 * flags used by alt_fd.

 *

 * ALT_FD_EXCL is used to mark a file descriptor as locked for exclusive

 * access, i.e. further calls to open() for the associated device should

 * fail.

 *

 * ALT_FD_DEV marks a dile descriptor as belonging to a device as oposed to a

 * filesystem.

 */

#define ALT_FD_EXCL 0x80000000

#define ALT_FD_DEV  0x40000000

#define ALT_FD_FLAGS_MASK (ALT_FD_EXCL | ALT_FD_DEV)

/*

 * "alt_dev_list" is the head of the linked list of registered devices.

 */

extern alt_llist alt_dev_list;

/*

 * "alt_fs_list" is the head of the linked list of registered filesystems.

 */

extern alt_llist alt_fs_list;

/*

 * "alt_fd_list_lock" is a semaphore used to ensure that access to the pool

 * of file descriptors is thread safe.

 */

ALT_EXTERN_SEM(alt_fd_list_lock)

/*

 * "alt_max_fd" is a 'high water mark'. It indicates the highest file

 * descriptor allocated. Use of this can save searching the entire pool

 * for active file descriptors, which helps avoid contention on access

 * to the file descriptor pool.

 */

extern alt_32 alt_max_fd;

/*

 * alt_io_redirect() is called at startup to redirect stdout, stdin, and

 * stderr to the devices named in the input arguments. By default these streams

 * are directed at /dev/null, and are then redirected using this function once

 * all of the devices have been registered within the system.

 */

extern void alt_io_redirect(const char* stdout_dev,

                            const char* stdin_dev,

                            const char* stderr_dev);

#ifdef __cplusplus

}

#endif

#endif /* __ALT_FILE_H__ */