fs_ffree.c

keil arm flash fs 最新版 在Ｋｅｉｌ ａｒｍ下使用

/*----------------------------------------------------------------------------
 *      R T L  -  F l a s h   F i l e   S y s t e m
 *----------------------------------------------------------------------------
 *      Name:    FS_FFREE.C 
 *      Purpose: Get File System Free Space Function
 *      Rev.:    V3.22
 *----------------------------------------------------------------------------
 *      This code is part of the RealView Run-Time Library.
 *      Copyright (c) 2004-2008 KEIL - An ARM Company. All rights reserved.
 *---------------------------------------------------------------------------*/

#include "File_Config.h"

/*--------------------------- ffree -----------------------------------------*/

U32 ffree (const char *drive) {
   /* Find a free space in the Flash File System. */
   IOB *fcb;
   int handle;
   U32 bl, free = 0;

   /* Find an unused _iob structure. */
   if ((handle = fs_find_iob ()) == EOF) {
      return (0);
   }
   fcb = &_iob[handle];
   /* Get the drive index. */
   fcb->drive = fs_get_drive (drive);
   if (fcb->drive == DRV_NONE && *drive == 0) {
      /* Empty string provided for a drive name. */
      fcb->drive = _DEF_DRIVE;
   }
   if (fcb->drive == DRV_NONE) {
      /* Invalid drive letter specified. */
      return (0);
   }
   if (fcb->drive == DRV_MCARD) {
      /* Calculate Free Memory for a Flash Card. */
      free = fat_free ();
      return (free);
   }
   /* Set drive parameters. */
   if (fs_set_params (fcb) == __FALSE) {
      return (0);
   }

   for (bl = 0; bl < fcb->NumSect; bl++) {
      /* Search all File Blocks for free space. */
      free += fs_get_freeMem (bl, fcb);
   }
   return (free);
}

/*----------------------------------------------------------------------------
 * end of file
 *---------------------------------------------------------------------------*/