/*****************************************************************************\
 * Copyright (c) 2004 Mark Aylett <mark@emantic.co.uk>                       *
 *                                                                           *
 * 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.                                    *
\*****************************************************************************/

static const char rcsid[] = "$Id: mar_file_c.c,v 1.3 2004/12/14 13:09:23 marayl Exp $";

#include "mar_file_c.h"

#include "mar_debug_c.h"
#include "mar_flags_c.h"
#include "mar_format_c.h"

#include <assert.h>
#include <errno.h>

#include <sys/types.h>

#if !defined(WIN32)
#include "unix/mar_file_c.c"
#else /* WIN32 */
#include "win/mar_file_c.c"
#endif /* WIN32 */

MAR_EXTERN int
mar_closefile_(int fd)
{
    return close(fd);
}

MAR_EXTERN int
mar_openfile_(const char* path, int flags, mode_t mode)
{
    int local;
    if (-1 == mar_toflags_(&local, flags))
        return -1;

    return open(path, local, mode);
}

MAR_EXTERN int
mar_extendfile_(int fd, size_t size)
{
    /**
     * The lseek function can be used to move the file pointer beyond the end
     * of the file, in which case any subsequent write operation should fill
     * the gap between the current end of file and the file pointer with zeros.
     *
     * Bug: On Windows 95/98 the gap is filled with garbage instead of zeros.
     */

    static const mar_byte_t ZERO = 0;

    off_t cur;
    int err;

    if (!size)
        return 0;

    /**
     * Store current file pointer for later restoration.
     */
    if (-1 == (cur = lseek(fd, 0, SEEK_CUR))) {

        MAR_DEBUG_MSG("Failed to extend file:"
                      " Bad call to lseek\n");
        return -1;
    }

    if (-1 == lseek(fd, (off_t)(size - 1), SEEK_END)) {

        MAR_DEBUG_MSG("Failed to extend file:"
                      " Bad call to lseek\n");
        return -1;
    }

    if (1 != write(fd, &ZERO, 1)) {

        MAR_DEBUG_MSG("Failed to extend file:"
                      " Bad call to write\n");
        goto fail;
    }

    /**
     * Ensure that gap is filled with zeros.
     */
    if (-1 == fsync(fd)) {

        MAR_DEBUG_MSG("Failed to extend file:"
                      " Bad call to fsync\n");
        goto fail;
    }

    /**
     * Restore original file pointer.
     */
    if (-1 == lseek(fd, cur, SEEK_SET)) {

        MAR_DEBUG_MSG("Failed to extend file:"
                      " Bad call to lseek\n");
        return -1;
    }

    return 0;

 fail:
    err = errno;
    lseek(fd, cur, SEEK_SET);
    errno = err;
    return -1;
}

MAR_EXTERN int
mar_syncfile_(int fd)
{
    int ret = fsync(fd);
    MAR_DEBUG_MSG("Failed to sync file:"
                  " Bad call to fsync\n");
    return ret;
}

MAR_EXTERN int
mar_truncatefile_(int fd, off_t size)
{
    int ret = ftruncate(fd, size);
    MAR_DEBUG_MSG("Failed to truncate file:"
                  " Bad call to ftruncate\n");
    return ret;
}

MAR_EXTERN int
mar_filesize_(int fd, size_t* size)
{
    assert(size);
    return mar_dofilesize_(fd, size);
}