syncobj.c
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/*------------------------------------------------------------------------*/
/* Sample code of OS dependent synchronization object controls */
/* for FatFs R0.07d (C)ChaN, 2009 */
/*------------------------------------------------------------------------*/
#include <windows.h> // Win32
//#include <ucos_ii.h> // uC/OS-II
#include "../ff.h"
#if _FS_REENTRANT
/*------------------------------------------------------------------------*/
/* Create a Synchronization Object for a Volume
/*------------------------------------------------------------------------*/
/* This function is called in f_mount function to create a new
/ synchronization object, such as semaphore and mutex. When a FALSE is
/ returned, the f_mount function fails with FR_INT_ERR.
*/
BOOL 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 */
)
{
BOOL ret;
*sobj = CreateMutex(NULL, FALSE, NULL); // Win32
ret = (*sobj != INVALID_HANDLE_VALUE) ? TRUE : FALSE; //
// *sobj = VolumeSemId[vol]; // uITRON (give a static created sync object)
// ret = TRUE; // The initial value of the semaphore must be 1.
// *sobj = OSMutexCreate(0, &err); // uC/OS-II
// ret = (err == OS_NO_ERR) ? TRUE : FALSE; //
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 FALSE is
/ returned, the f_mount function fails with FR_INT_ERR.
*/
BOOL 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 */
)
{
BOOL ret;
ret = CloseHandle(sobj); // Win32
// ret = TRUE; // uITRON (nothing to do)
// OSMutexDel(sobj, OS_DEL_ALWAYS, &err); // uC/OS-II
// ret = (err == OS_NO_ERR) ? TRUE : FALSE; //
return ret;
}
/*------------------------------------------------------------------------*/
/* Request Grant to Access the Volume */
/*------------------------------------------------------------------------*/
/* This function is called on entering file functions to lock the volume.
/ When a FALSE is returned, the file function fails with FR_TIMEOUT.
*/
BOOL ff_req_grant ( /* TRUE:Got a grant to access the volume, FALSE:Could not get a grant */
_SYNC_t sobj /* Sync object to wait */
)
{
BOOL ret;
ret = (WaitForSingleObject(sobj, _FS_TIMEOUT) == WAIT_OBJECT_0) ? TRUE : FALSE; // Win32
// ret = (wai_sem(sobj) == E_OK) ? TRUE : FALSE; // uITRON
// OSMutexPend(sobj, _FS_TIMEOUT, &err)); // uC/OS-II
// ret = (err == OS_NO_ERR) ? TRUE : FALSE; //
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 */
)
{
ReleaseMutex(sobj); // Win32
// sig_sem(sobj); // uITRON
// OSMutexPost(sobj); // uC/OS-II
}
#else
#error This file is not needed in this configuration.
#endif