/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 */
#include "fs.h"
#include "fsdata.h"   /* file-system data generated by makefsdata.pl script */

#include <string.h>

/*--------------------------------------------------------------------------*/
/* Define the number of open files that we can support. */
#ifndef LWIP_MAX_OPEN_FILES
#define LWIP_MAX_OPEN_FILES     10
#endif

/* Define the file system memory allocation structure. */
struct fs_table {
    struct fs_file file;
    int inuse;
};

/* Allocate file system memory */
struct fs_table fs_memory[LWIP_MAX_OPEN_FILES];

/*--------------------------------------------------------------------------*/
static struct fs_file *fs_malloc(void) {
    int i;
    for (i = 0; i < LWIP_MAX_OPEN_FILES; i++) {
        if (fs_memory[i].inuse == 0) {
            fs_memory[i].inuse = 1;
            return (&fs_memory[i].file);
        }
    }
    return (NULL);
}

/*--------------------------------------------------------------------------*/
static void fs_free(struct fs_file *file) {
    int i;
    for (i = 0; i < LWIP_MAX_OPEN_FILES; i++) {
        if (&fs_memory[i].file == file) {
            fs_memory[i].inuse = 0;
            break;
        }
    }
    return;
}

/*--------------------------------------------------------------------------*/
struct fs_file *fs_open(char const *name) {
    struct fs_file *file;
    const struct fsdata_file *f;

    file = fs_malloc();
    if (file == NULL) {
        return NULL;
    }

    for (f = FS_ROOT; f != NULL; f = f->next) {
        if (!strcmp(name, (char *)f->name)) {
            file->data = (char *)f->data;
            file->len = f->len;
            file->index = f->len;
            file->pextension = NULL;
            return file;
        }
    }
    fs_free(file);
    return NULL;
}

/*--------------------------------------------------------------------------*/
void fs_close(struct fs_file *file) {
    fs_free(file);
}
/*--------------------------------------------------------------------------*/
int fs_read(struct fs_file *file, char *buffer, int count) {
    int read;

    if (file->index == file->len) {
        return -1;
    }

    read = file->len - file->index;
    if (read > count) {
        read = count;
    }

    memcpy(buffer, (file->data + file->index), read);
    file->index += read;

    return (read);
}