/*
 * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Hyra nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>

FILE*
fopen(const char *pathname, const char *mode)
{
    int open_flags;
    int fd;

    if (mode == NULL)
        return NULL;

    /* Determine open flags */
    switch (mode[0]) {
    case 'r':
        if (mode[1] == '+') {
            open_flags = O_RDWR;
        } else {
            open_flags = O_RDONLY;
        }
        break;
    case 'w':
    case 'a':
    /* TODO: Change this once O_CREAT, O_TRUNC, and O_APPEND are added */
        if (mode[1] == '+') {
            open_flags = O_RDWR;
        } else {
            open_flags = O_WRONLY;
        }
        break;
    default:
        return NULL;
    }

    /* Try to open file */
    fd = open(pathname, open_flags);
    if (fd == -1)
        return NULL;

    /* Create stream with fdopen */
    return fdopen(fd, mode);
}