syscall.c

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/*------------------------------------------------------------------------*/
/* Sample code of OS dependent controls for FatFs                         */
/* (C)ChaN, 2014                                                          */
/*------------------------------------------------------------------------*/

#include <stdlib.h>     /* ANSI memory controls */
#include "../ff.h"

#if _FS_REENTRANT
/*-----------------------------------------------------------------------
 Create a Synchronization Object
------------------------------------------------------------------------
 This function is called in f_mount function to create a new
 synchronization object, such as semaphore and mutex. When a zero is
 returned, the f_mount function fails with FR_INT_ERR.
*/

int ff_cre_syncobj (    /* TRUE:Function succeeded, FALSE:Could not create due to any error */
    BYTE vol,           /* Corresponding logical drive being processed */
    _SYNC_t *sobj       /* Pointer to return the created sync object */
)
{
  int ret;
  
  osSemaphoreDef(SEM);
  *sobj = osSemaphoreCreate(osSemaphore(SEM), 1);       
  ret = (*sobj != NULL);
  
  return ret;
}



/*------------------------------------------------------------------------*/
/* Delete a Synchronization Object                                        */
/*------------------------------------------------------------------------*/
/* This function is called in f_mount function to delete a synchronization
/  object that created with ff_cre_syncobj function. When a zero is
/  returned, the f_mount function fails with FR_INT_ERR.
*/

int ff_del_syncobj (    /* TRUE:Function succeeded, FALSE:Could not delete due to any error */
    _SYNC_t sobj        /* Sync object tied to the logical drive to be deleted */
)
{
  osSemaphoreDelete (sobj);
  return 1;
}



/*------------------------------------------------------------------------*/
/* Request Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on entering file functions to lock the volume.
/  When a zero is returned, the file function fails with FR_TIMEOUT.
*/

int ff_req_grant (  /* TRUE:Got a grant to access the volume, FALSE:Could not get a grant */
    _SYNC_t sobj    /* Sync object to wait */
)
{
  int ret = 0;
  
  if(osSemaphoreWait(sobj, _FS_TIMEOUT) == osOK)
  {
    ret = 1;
  }
  
  return ret;
}



/*------------------------------------------------------------------------*/
/* Release Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on leaving file functions to unlock the volume.
*/

void ff_rel_grant (
    _SYNC_t sobj    /* Sync object to be signaled */
)
{
  osSemaphoreRelease(sobj);
}

#endif




#if _USE_LFN == 3   /* LFN with a working buffer on the heap */
/*------------------------------------------------------------------------*/
/* Allocate a memory block                                                */
/*------------------------------------------------------------------------*/
/* If a NULL is returned, the file function fails with FR_NOT_ENOUGH_CORE.
*/

void* ff_memalloc ( /* Returns pointer to the allocated memory block */
    UINT msize      /* Number of bytes to allocate */
)
{
    return malloc(msize);   /* Allocate a new memory block with POSIX API */
}


/*------------------------------------------------------------------------*/
/* Free a memory block                                                    */
/*------------------------------------------------------------------------*/

void ff_memfree (
    void* mblock    /* Pointer to the memory block to free */
)
{
    free(mblock);   /* Discard the memory block with POSIX API */
}

#endif