/* $NetBSD: memfs.c,v 1.1 2011/03/06 18:22:13 phx Exp $ */

/*-
* Copyright (c) 2011 Frank Wille.
* All rights reserved.
*
* Written by Frank Wille for The NetBSD Project.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <sys/param.h>

#include <lib/libsa/stand.h>

#include "globals.h"
#include "memfs.h"

struct memhandle {
       char *base;
       off_t off;
};

int
mem_open(const char *path, struct open_file *f)
{
       struct memhandle *mh;

       mh = alloc(sizeof(struct memhandle));
       if (mh == NULL)
               return ENOMEM;
       mh->base = (char *)read_hex(path);
       mh->off = 0;
       f->f_fsdata = mh;
       return 0;
}

#ifndef LIBSA_NO_FS_CLOSE
int
mem_close(struct open_file *f)
{

       dealloc(f->f_fsdata, sizeof(struct memhandle));
       return 0;
}
#endif

int
mem_read(struct open_file *f, void *buf, size_t size, size_t *resid)
{
       struct memhandle *mh;

       mh = f->f_fsdata;
       memcpy(buf, mh->base + mh->off, size);
       mh->off += size;
       if (resid)
               *resid = 0;
       return 0;
}

#ifndef LIBSA_NO_FS_WRITE
int
mem_write(struct open_file *f, void *buf, size_t size, size_t *resid)
{
       struct memhandle *mh;

       mh = f->f_fsdata;
       memcpy(mh->base + mh->off, buf, size);
       mh->off += size;
       if (resid)
               *resid = 0;
       return 0;
}
#endif

#ifndef LIBSA_NO_FS_SEEK
off_t
mem_seek(struct open_file *f, off_t offset, int where)
{
       struct memhandle *mh;

       mh = f->f_fsdata;
       switch (where) {
       case SEEK_SET:
               mh->off = offset;
               break;
       case SEEK_CUR:
               mh->off += offset;
               break;
       default:
               errno = EOFFSET;
               return -1;
       }
       return mh->off;
}
#endif

int
mem_stat(struct open_file *f, struct stat *sb)
{

       return EIO;
}