r_misc.c

这是ucfs文件系统源代码

/*
**********************************************************************
*                          Micrium, Inc.
*                      949 Crestview Circle
*                     Weston,  FL 33327-1848
*
*                            uC/FS
*
*             (c) Copyright 2001 - 2006, Micrium, Inc.
*                      All rights reserved.
*
***********************************************************************

----------------------------------------------------------------------
File        : r_misc.c
Purpose     : Device Driver for simple array in RAM
---------------------------END-OF-HEADER------------------------------
*/

/*********************************************************************
*
*             #include Section
*
**********************************************************************
*/

#include "fs_dev.h"
#include "fs_lbl.h"
#include "FS_ConfDefaults.h"        /* FS Configuration */

#if FS_USE_RAMDISK_DRIVER

#include "fs_api.h"
#include "fs_clib.h"
#include "FS_Debug.h"

#ifdef WIN32
#include <windows.h>
#endif

/*********************************************************************
*
*        Static data
*
**********************************************************************
*/

typedef struct {
  FS_U8 aaaData[FS_RAMDISK_MAXUNIT][FS_RR_BLOCKNUM][FS_RAMDISK_SECTOR_SIZE];
} RAMDISK;

#ifndef FS_RAMDISK_ADDR
static RAMDISK _RamDrive;
static RAMDISK * _pRAMDrive = &_RamDrive;
#else
static RAMDISK * _pRAMDrive = (RAMDISK *) FS_RAMDISK_ADDR;
#endif

#ifdef WIN32
static int _ReadDelay;
static int _WriteDelay;
#endif

/*********************************************************************
*
*       Static code
*
**********************************************************************
*/


/*********************************************************************
*
*       _DevStatus
*
*  Description:
*    FS driver function. Get status of the RAM disk.
*
*  Parameters:
*    Unit    - Device number.
*
*  Return value:
*    FS_MEDIA_STATEUNKNOWN if the state of the media is unknown.
*    FS_MEDIA_ISNOTPRESENT if no card is present.
*    FS_MEDIA_ISPRESENT if a card is present.
*/

static int _DevStatus(FS_U8 Unit) {
  FS_USE_PARA(Unit);
  return FS_MEDIA_IS_PRESENT;
}


/*********************************************************************
*
*       _DevRead
*
*  Description:
*    FS driver function. Read a sector from the RAM disk.
*
*  Parameters:
*    Unit        - Unit number.
*    Sector      - Sector to be read from the device.
*    pBuffer     - Pointer to buffer for storing the data.
*
*  Return value:
*    ==0         - Sector has been read and copied to pBuffer.
*    <0          - An error has occured.
*/
static int _DevRead(FS_U8 Unit, FS_U32 Sector, void *pBuffer) {
  if (Sector >= FS_RR_BLOCKNUM) {
    FS_DEBUG_ERROROUT("_DevRead: Sector out of range\n");
    return -1;
  }
  FS_MEMCPY(pBuffer, &_pRAMDrive->aaaData[Unit][Sector][0], FS_RAMDISK_SECTOR_SIZE);
#ifdef WIN32
  Sleep(_ReadDelay);
#endif
  return 0;
}

/*********************************************************************
*
*       _ReadBurst
*
*  Description:
*    Read multiple sectors.
*
*  Parameters:
*    Unit        - Unit number.
*    SectorNo    - First sector to be read from the device.
*    NumSectors  - Number of sectors to be read from the device.
*    pBuffer     - Pointer to buffer for storing the data.
*
*  Return value:
*    ==0         - Sector has been read and copied to pBuffer.
*    <0          - An error has occured.
*/
static int _ReadBurst(FS_U8 Unit, FS_U32 SectorNo, FS_U32 NumSectors, void *pBuffer) {
  if (SectorNo + NumSectors > FS_RR_BLOCKNUM) {
    FS_DEBUG_ERROROUT("_ReadBurst: Sector out of range\n");
    return -1;
  }
  FS_MEMCPY(pBuffer, &_pRAMDrive->aaaData[Unit][SectorNo][0], NumSectors * FS_RAMDISK_SECTOR_SIZE);
#ifdef WIN32
  Sleep(_ReadDelay);
#endif
  return 0;
}

/*********************************************************************
*
*       _WriteBurst
*
*  Description:
*    Read multiple sectors.
*
*  Parameters:
*    Unit        - Unit number.
*    SectorNo    - First sector to be written to the device.
*    NumSectors  - Number of sectors to be written to the device.
*    pBuffer     - Pointer to buffer for holding the data.
*
*  Return value:
*    ==0         - O.K.: Sector has been written to device.
*    <0          - An error has occured.
*/
static int _WriteBurst(FS_U8 Unit, FS_U32 SectorNo, FS_U32 NumSectors, const void *pBuffer) {
  if (SectorNo + NumSectors > FS_RR_BLOCKNUM) {
    FS_DEBUG_ERROROUT("_WriteBurst: Sector out of range\n");
    return -1;
  }
  FS_MEMCPY(&_pRAMDrive->aaaData[Unit][SectorNo][0], pBuffer, NumSectors * FS_RAMDISK_SECTOR_SIZE);
#ifdef WIN32
  Sleep(_WriteDelay);
#endif
  return 0;
}


/*********************************************************************
*
*       _DevWrite
*
*  Description:
*    FS driver function. Write sector to the RAM disk.
*
*  Parameters:
*    Unit        - Unit number.
*    Sector      - Sector to be written to the device.
*    pBuffer     - Pointer to data to be stored.
*
*  Return value:
*    ==0         - Sector has been written to the device.
*    <0          - An error has occured.
*/

static int _DevWrite(FS_U8 Unit, FS_U32 Sector, const void *pBuffer) {
  if (Sector >= FS_RR_BLOCKNUM) {
    FS_DEBUG_ERROROUT("_DevWrite: Sector out of range\n");
    return -1;
  }
  FS_MEMCPY(&_pRAMDrive->aaaData[Unit][Sector][0], pBuffer, FS_RAMDISK_SECTOR_SIZE);
#ifdef WIN32
  Sleep(_WriteDelay);
#endif
  return 0;
}


/*********************************************************************
*
*       _DevIoCtl
*
*  Description:
*    FS driver function. Execute device command.
*
*  Parameters:
*    Unit        - Unit number.
*    Cmd         - Command to be executed.
*    Aux         - Parameter depending on command.
*    pBuffer     - Pointer to a buffer used for the command.
*
*  Return value:
*    Command specific. In general a negative value means an error.
*/
static int _DevIoCtl(FS_U8 Unit, FS_I32 Cmd, FS_I32 Aux, void *pBuffer) {
  FS_DEV_INFO *pInfo;
  FS_USE_PARA(Unit);
  FS_USE_PARA(Aux);
  switch (Cmd) {
  case FS_CMD_GET_DEVINFO:
    if (!pBuffer) {
      return -1;
    }
    pInfo = (FS_DEV_INFO *)pBuffer;
    pInfo->NumSectors      = FS_RR_BLOCKNUM;
    pInfo->BytesPerSector  = FS_RAMDISK_SECTOR_SIZE;
    break;
#ifdef WIN32
  case FS_CMD_SET_DELAY:
    _ReadDelay  = Aux;
    _WriteDelay = (int)pBuffer;
    break;
#endif

  default:
    break;
  }
  return 0;
}

/*********************************************************************
*
*       Public data
*
**********************************************************************
*/

const FS_DEVICE_TYPE FS__ramdevice_driver = {
  "ram",
  FS_RAMDISK_MAXUNIT,
  _DevStatus,
  _DevRead,
  _DevWrite,
  _DevIoCtl,
  _ReadBurst,      /* Optional function */
  _WriteBurst,     /* Optional function */
  NULL,
  NULL
};

#endif /* FS_USE_RAMDISK_DRIVER */

/*************************** End of file ****************************/