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#ifndef __ALT_ERRNO_H__

#define __ALT_ERRNO_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.                       *

*                                                                             *

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

/*

 * errno is defined in <errno.h> so that it uses the thread local version

 * stored in the location pointed to by "_impure_ptr". This means that the

 * accesses to errno within the HAL library can cause the entirety of

 * of the structure pointed to by "_impure_ptr" to be added to the

 * users application. This can be undesirable in very small footprint systems.

 *

 * To avoid this happening, the HAL uses the macro ALT_ERRNO, defined below,

 * to access errno, rather than accessing it directly. This macro will only

 * use the thread local version if some other code has already caused it to be

 * included into the system, otherwise it will use the global errno value.

 *

 * This causes a slight increases in code size where errno is accessed, but

 * can lead to significant overall benefits in very small systems. The

 * increase is inconsequential when compared to the size of the structure

 * pointed to by _impure_ptr.

 *

 * Note that this macro accesses __errno() using an externally declared

 * function pointer (alt_errno). This is done so that the function call uses the

 * subroutine call instruction via a register rather than an immediate address.

 * This is important in the case that the code has been linked for a high

 * address, but __errno() is not being used. In this case the weak linkage

 * would have resulted in the instruction: "call 0" which would fail to link.

 */

extern int* (*alt_errno) (void);

/* Must define this so that values such as EBADFD are defined in errno.h. */

#define __LINUX_ERRNO_EXTENSIONS__

#include <errno.h>

#include "alt_types.h"

#undef errno

extern int errno;

static ALT_INLINE int* alt_get_errno(void)

{

  return ((alt_errno) ? alt_errno() : &errno);

}

#define ALT_ERRNO *alt_get_errno()

#endif /* __ALT_ERRNO_H__ */