/*****************************************************************************************
 Copyright (c) 2002-2004 The UbixOS Project
 All rights reserved.

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 permitted provided that the following conditions are met:

 Redistributions of source code must retain the above copyright notice, this list of
 conditions, the following disclaimer and the list of authors.  Redistributions in binary
 form must reproduce the above copyright notice, this list of conditions, the following
 disclaimer and the list of authors in the documentation and/or other materials provided
 with the distribution. Neither the name of the UbixOS Project 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.

 $Id: vfs.c 158 2016-01-19 02:08:13Z reddawg $

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

#include <vfs/vfs.h>
#include <ubixos/vitals.h>
#include <lib/kmalloc.h>
#include <lib/kprintf.h>
#include <lib/string.h>
#include <sys/kern_descrip.h>

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

Function: void vfs_init();

Description: This Function Initializes The VFS Layer

Notes:

02/20/2004 - Approved for quality

************************************************************************/
int vfs_init() {
  /* Set up default fileSystems list */
  systemVitals->fileSystems = 0x0;

  /* Print information */
  kprintf("vfs0: loaded at address: [0x%X]\n",systemVitals->fileSystems);

  /* Return so we know things went well */
  return(0x0);
  }

struct fileSystem *vfsFindFS(int vfsType) {
  struct fileSystem *tmp = 0x0;

  /* Search For File System */
  for (tmp=systemVitals->fileSystems;tmp;tmp=tmp->next) {
    /* If Found Return File System */
    if (tmp->vfsType == vfsType) {
      return(tmp);
      }
    }

  /* If FS Not Found Return NULL */
  return(0x0);
  }

/*!
 * \brief register a file system
 *
 * This registers a new filesystem into the vfs which is referenced when trying to mount a device
 *
 * \param newFS pointer to fileSystem structure
 */
int vfsRegisterFS(struct fileSystem newFS) {
/*
int vfsType,
void *vfsInitFS,
void *vfsRead,
void *vfsWrite,
void *vfsOpenFile,
void *vfsUnlink,
void *vfsMakeDir,
void *vfsRemDir,
void *vfsSync) {
 */
  struct fileSystem *tmpFs = 0x0;

  if (vfsFindFS(newFS.vfsType) != 0x0) {
    kprintf("FS Is already Registered\n"); 
    return(0x1);
    }

  /* Allocate Memory */
  tmpFs = (struct fileSystem *)kmalloc(sizeof(struct fileSystem));
  if (tmpFs == NULL) {
	kprintf("vfsRegisterFS: memory allocation failed\n");
    /* Memory Allocation Failed */
    return(0x1);
    }

  /* Set Up FS Defaults */

/* 2004 7-16-2004 mji 
 * Old method:
 * tmpFs->vfsType       = newFS.vfsType;
 * tmpFs->vfsInitFS     = newFS.vfsInitFS;
 * tmpFs->vfsRead       = newFS.vfsRead;
 * tmpFs->vfsWrite      = newFS.vfsWrite;
 * tmpFs->vfsOpenFile   = newFS.vfsOpenFile;
 * tmpFs->vfsUnlink     = newFS.vfsUnlink;
 * tmpFs->vfsMakeDir    = newFS.vfsMakeDir;
 * tmpFs->vfsRemDir     = newFS.vfsRemDir;
 * tmpFs->vfsSync       = newFS.vfsSync;
 */
 /* new method: */

  memcpy(tmpFs, &newFS, sizeof(struct fileSystem)); 
  if (!systemVitals->fileSystems) {
    tmpFs->prev               = 0x0;
    tmpFs->next               = 0x0;
    systemVitals->fileSystems = tmpFs;
    }
  else {
    tmpFs->prev                     = 0x0;
    tmpFs->next                     = systemVitals->fileSystems;
    systemVitals->fileSystems->prev = tmpFs;
    systemVitals->fileSystems       = tmpFs;
    }

  return(0x0);
  }

/*!
 * \brief entry point for open syscall
 *
 * \param *td pointer to callers thread
 * \param *uap pointer to user space arguements for call
 *
 * \return index to file descriptor
 */
int sys_open(struct thread *td, struct sys_open_args *args) {
  int          error = 0x0;
  int          index = 0x0;
  struct file *nfp   = 0x0;

  error = falloc(td,&nfp,&index);

  if (error)
     return(error);

  strcpy(nfp->path, args->path);

  nfp->fd = fopen(args->path,"r");
  if (nfp->fd == 0x0)
    td->td_retval[0] = -1;
  else
    td->td_retval[0] = index;
  return (error);
  }

/* HACK */
int fstatfs(struct thread *td, struct fstatfs_args *args) {
  int error = 0x0;
  args->buf->f_mntonname[0] = '/';
  args->buf->f_mntonname[1] = '\0';
  args->buf->f_flags = 0x0;
  return(error);
  }

/***
 END
 ***/