/**
* @private
* @brief Flushes all Write cache buffers with no active Handles.
*
* @param pIoman IOMAN Object.
*
* @return FF_ERR_NONE on Success.
**/
FF_ERROR FF_FlushCache(FF_IOMAN *pIoman) {
FF_T_UINT16 i,x;
if(!pIoman) {
return FF_ERR_NULL_POINTER | FF_FLUSHCACHE;
}
FF_PendSemaphore(pIoman->pSemaphore);
{
for(i = 0; i < pIoman->CacheSize; i++) {
if((pIoman->pBuffers + i)->NumHandles == 0 && (pIoman->pBuffers + i)->Modified == FF_TRUE) {
FF_BlockWrite(pIoman, (pIoman->pBuffers + i)->Sector, 1, (pIoman->pBuffers + i)->pBuffer);
// Buffer has now been flushed, mark it as a read buffer and unmodified.
(pIoman->pBuffers + i)->Mode = FF_MODE_READ;
(pIoman->pBuffers + i)->Modified = FF_FALSE;
// Search for other buffers that used this sector, and mark them as modified
// So that further requests will result in the new sector being fetched.
for(x = 0; x < pIoman->CacheSize; x++) {
if(x != i) {
if((pIoman->pBuffers + x)->Sector == (pIoman->pBuffers + i)->Sector && (pIoman->pBuffers + x)->Mode == FF_MODE_READ) {
(pIoman->pBuffers + x)->Modified = FF_TRUE;
}
}
}
}
}
}
FF_ReleaseSemaphore(pIoman->pSemaphore);
return FF_ERR_NONE;
}
/**
* @public
* @brief Unmounts the active partition.
*
* @param pIoman FF_IOMAN Object.
*
* @return FF_ERR_NONE on success.
**/
FF_ERROR FF_UnmountPartition(FF_IOMAN *pIoman) {
FF_ERROR RetVal = FF_ERR_NONE;
#ifdef FF_MIRROR_FATS_UMOUNT
FF_T_UINT i, y;
FF_BUFFER *pBuffer;
#endif
if(!pIoman || !pIoman->pPartition) {
return FF_ERR_NULL_POINTER | FF_UNMOUNTPARTITION;
}
if (!pIoman->pPartition->PartitionMounted)
return FF_ERR_NONE;
FF_PendSemaphore(pIoman->pSemaphore); // Ensure that there are no File Handles
{
if(!FF_ActiveHandles(pIoman)) {
if(pIoman->FirstFile == NULL) {
// Release Semaphore to call this function!
FF_ReleaseSemaphore(pIoman->pSemaphore);
RetVal = FF_FlushCache(pIoman); // Flush any unwritten sectors to disk.
if(FF_isERR(RetVal)) {
return RetVal;
}
// Reclaim Semaphore
FF_PendSemaphore(pIoman->pSemaphore);
pIoman->pPartition->PartitionMounted = FF_FALSE;
#ifdef FF_MIRROR_FATS_UMOUNT
FF_ReleaseSemaphore(pIoman->pSemaphore);
for(i = 0; i < pIoman->pPartition->SectorsPerFAT; i++) {
pBuffer = FF_GetBuffer(pIoman, pIoman->pPartition->FatBeginLBA + i, FF_MODE_READ);
if(!pBuffer) {
RetVal = FF_ERR_DEVICE_DRIVER_FAILED | FF_UNMOUNTPARTITION;
break;
}
for(y = 0; y < pIoman->pPartition->NumFATS; y++) {
FF_BlockWrite(pIoman, pIoman->pPartition->FatBeginLBA + (y*pIoman->pPartition->SectorsPerFAT) + i, 1, pBuffer->pBuffer, FF_FALSE);
}
}
FF_PendSemaphore(pIoman->pSemaphore);
#endif
} else {
RetVal = FF_ERR_IOMAN_ACTIVE_HANDLES | FF_UNMOUNTPARTITION;
}
} else {
RetVal = FF_ERR_IOMAN_ACTIVE_HANDLES | FF_UNMOUNTPARTITION; // Active handles found on the cache.
}
}
FF_ReleaseSemaphore(pIoman->pSemaphore);
return RetVal;
}
/**
* @private
* @brief Releases a buffer resource.
*
* @param pIoman Pointer to an FF_IOMAN object.
* @param pBuffer Pointer to an FF_BUFFER object.
*
**/
FF_ERROR FF_ReleaseBuffer(FF_IOMAN *pIoman, FF_BUFFER *pBuffer) {
FF_ERROR Error = FF_ERR_NONE;
// Protect description changes with a semaphore.
FF_PendSemaphore(pIoman->pSemaphore);
{
if (pBuffer->NumHandles) {
pBuffer->NumHandles--;
} else {
//printf ("FF_ReleaseBuffer: buffer not claimed\n");
}
#ifdef FF_CACHE_WRITE_THROUGH
if(pBuffer->Modified == FF_TRUE) {
Error = FF_BlockWrite(pIoman, pBuffer->Sector, 1, pBuffer->pBuffer, FF_TRUE);
if(!FF_isERR(Error)) { // Ensure if an error occurs its still possible to write the block again.
pBuffer->Modified = FF_FALSE;
}
}
#endif
}
FF_ReleaseSemaphore(pIoman->pSemaphore);
return Error;
}
static FF_ERROR FF_WriteClusters(FF_FILE *pFile, FF_T_UINT32 Count, FF_T_UINT8 *buffer) {
FF_T_UINT32 ulSectors;
FF_T_UINT32 SequentialClusters = 0;
FF_T_UINT32 nItemLBA;
FF_T_SINT32 slRetVal;
FF_ERROR Error;
while(Count != 0) {
if((Count - 1) > 0) {
SequentialClusters = FF_GetSequentialClusters(pFile->pIoman, pFile->AddrCurrentCluster, (Count - 1), &Error);
if(Error) {
return Error;
}
}
ulSectors = (SequentialClusters + 1) * pFile->pIoman->pPartition->SectorsPerCluster;
nItemLBA = FF_Cluster2LBA(pFile->pIoman, pFile->AddrCurrentCluster);
nItemLBA = FF_getRealLBA(pFile->pIoman, nItemLBA);
slRetVal = FF_BlockWrite(pFile->pIoman, nItemLBA, ulSectors, buffer);
if(slRetVal < 0) {
return slRetVal;
}
Count -= (SequentialClusters + 1);
pFile->AddrCurrentCluster = FF_TraverseFAT(pFile->pIoman, pFile->AddrCurrentCluster, (SequentialClusters + 1), &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += (SequentialClusters + 1);
buffer += ulSectors * pFile->pIoman->BlkSize;
SequentialClusters = 0;
}
return 0;
}
FF_BUFFER *FF_GetBuffer(FF_IOMAN *pIoman, FF_T_UINT32 Sector, FF_T_UINT8 Mode) {
FF_BUFFER *pBuffer;
FF_BUFFER *pBufLRU = NULL;
FF_BUFFER *pBufLHITS = NULL;
FF_BUFFER *pBufMatch = NULL;
FF_T_UINT32 i;
while(!pBufMatch) {
FF_PendSemaphore(pIoman->pSemaphore);
{
pBuffer = pIoman->pBuffers;
// HT if a perfect match has priority, find that first
for(i = 0; i < pIoman->CacheSize; i++, pBuffer++) {
pBuffer = (pIoman->pBuffers + i);
if(pBuffer->Sector == Sector && pBuffer->Valid == FF_TRUE) {
pBufMatch = pBuffer;
break; // Why look further if you found a perfect match?
}
}
if(pBufMatch) {
// A Match was found process!
if(Mode == FF_MODE_READ && pBufMatch->Mode == FF_MODE_READ) {
pBufMatch->NumHandles += 1;
pBufMatch->Persistance += 1;
FF_ReleaseSemaphore(pIoman->pSemaphore);
return pBufMatch;
}
if(pBufMatch->Mode == FF_MODE_WRITE && pBufMatch->NumHandles == 0) { // This buffer has no attached handles.
pBufMatch->Mode = Mode;
pBufMatch->NumHandles = 1;
pBufMatch->Persistance += 1;
FF_ReleaseSemaphore(pIoman->pSemaphore);
return pBufMatch;
}
if(pBufMatch->Mode == FF_MODE_READ && Mode == FF_MODE_WRITE && pBufMatch->NumHandles == 0) {
pBufMatch->Mode = Mode;
pBufMatch->Modified = FF_TRUE;
pBufMatch->NumHandles = 1;
pBufMatch->Persistance += 1;
FF_ReleaseSemaphore(pIoman->pSemaphore);
return pBufMatch;
}
pBufMatch = NULL; // Sector is already in use, keep yielding until its available!
} else {
pBuffer = pIoman->pBuffers;
for(i = 0; i < pIoman->CacheSize; i++, pBuffer++) {
if(pBuffer->NumHandles == 0) {
pBuffer->LRU += 1;
if(!pBufLRU) {
pBufLRU = pBuffer;
}
if(!pBufLHITS) {
pBufLHITS = pBuffer;
}
if(pBuffer->LRU >= pBufLRU->LRU) {
if(pBuffer->LRU == pBufLRU->LRU) {
if(pBuffer->Persistance > pBufLRU->Persistance) {
pBufLRU = pBuffer;
}
} else {
pBufLRU = pBuffer;
}
}
if(pBuffer->Persistance < pBufLHITS->Persistance) {
pBufLHITS = pBuffer;
}
}
}
if(pBufLRU) {
// Process the suitable candidate.
if(pBufLRU->Modified == FF_TRUE) {
FF_BlockWrite(pIoman, pBufLRU->Sector, 1, pBufLRU->pBuffer);
}
pBufLRU->Mode = Mode;
pBufLRU->Persistance = 1;
pBufLRU->LRU = 0;
pBufLRU->NumHandles = 1;
pBufLRU->Sector = Sector;
if(Mode == FF_MODE_WRITE) {
pBufLRU->Modified = FF_TRUE;
} else {
pBufLRU->Modified = FF_FALSE;
}
FF_BlockRead(pIoman, Sector, 1, pBufLRU->pBuffer);
pBufLRU->Valid = FF_TRUE;
FF_ReleaseSemaphore(pIoman->pSemaphore);
return pBufLRU;
}
}
}
FF_ReleaseSemaphore(pIoman->pSemaphore);
FF_Yield(); // Better to go asleep to give low-priority task a chance to release buffer(s)
}
return pBufMatch; // Return the Matched Buffer!
}
FF_BUFFER *FF_GetBuffer(FF_IOMAN *pIoman, FF_T_UINT32 Sector, FF_T_UINT8 Mode) {
FF_BUFFER *pBuffer;
FF_BUFFER *pBufLRU;
// FF_BUFFER *pBufLHITS = NULL; // Wasn't use anymore?
FF_BUFFER *pBufMatch = NULL;
FF_T_SINT32 RetVal;
FF_T_INT LoopCount = FF_GETBUFFER_WAIT_TIME;
FF_T_INT cacheSize = pIoman->CacheSize;
if (cacheSize <= 0) {
return NULL;
}
while(!pBufMatch) {
if (!--LoopCount) {
//
// *pError = FF_ERR_IOMAN_GETBUFFER_TIMEOUT;
//
return NULL;
}
FF_PendSemaphore(pIoman->pSemaphore);
{
for(pBuffer = pIoman->pBuffers; pBuffer < pIoman->pBuffers + cacheSize; pBuffer++) {
if(pBuffer->Sector == Sector && pBuffer->Valid) {
pBufMatch = pBuffer;
break; // Don't look further if you found a perfect match
}
}
if(pBufMatch) {
// A Match was found process!
if(Mode == FF_MODE_READ && pBufMatch->Mode == FF_MODE_READ) {
pBufMatch->NumHandles += 1;
pBufMatch->Persistance += 1;
break;
}
if(pBufMatch->NumHandles == 0) {
pBufMatch->Mode = (Mode & FF_MODE_RD_WR);
if((Mode & FF_MODE_WRITE) != 0) { // This buffer has no attached handles.
pBufMatch->Modified = FF_TRUE;
}
pBufMatch->NumHandles = 1;
pBufMatch->Persistance += 1;
break;
}
pBufMatch = NULL; // Sector is already in use, keep yielding until its available!
} else {
pBufLRU = NULL; // So put them to NULL here
for(pBuffer = pIoman->pBuffers; pBuffer < pIoman->pBuffers + cacheSize; pBuffer++) {
if(pBuffer->NumHandles)
continue; // Occupied
pBuffer->LRU += 1;
if(!pBufLRU) {
pBufLRU = pBuffer;
}
if(pBuffer->LRU > pBufLRU->LRU ||
(pBuffer->LRU == pBufLRU->LRU && pBuffer->Persistance > pBufLRU->Persistance)) {
pBufLRU = pBuffer;
}
}
// Choose a suitable buffer!
if(pBufLRU) {
// Process the suitable candidate.
if(pBufLRU->Modified == FF_TRUE) {
// Along with the FF_TRUE parameter to indicate semapahore has been claimed
RetVal = FF_BlockWrite(pIoman, pBufLRU->Sector, 1, pBufLRU->pBuffer, FF_TRUE);
if (RetVal < 0) {
pBufMatch = NULL;
break;
}
}
if (Mode == FF_MODE_WR_ONLY) {
memset (pBufLRU->pBuffer, '\0', pIoman->BlkSize);
} else {
RetVal = FF_BlockRead(pIoman, Sector, 1, pBufLRU->pBuffer, FF_TRUE);
if (RetVal < 0) {
pBufMatch = NULL;
break;
}
}
pBufLRU->Mode = (Mode & FF_MODE_RD_WR);
pBufLRU->Persistance = 1;
pBufLRU->LRU = 0;
pBufLRU->NumHandles = 1;
pBufLRU->Sector = Sector;
pBufLRU->Modified = (Mode & FF_MODE_WRITE) != 0;
pBufLRU->Valid = FF_TRUE;
pBufMatch = pBufLRU;
break;
}
}
}
FF_ReleaseSemaphore(pIoman->pSemaphore);
// Better to go asleep to give low-priority task a chance to release buffer(s)
FF_Sleep (FF_GETBUFFER_SLEEP_TIME);
} // while(!pBufMatch)
FF_ReleaseSemaphore(pIoman->pSemaphore);
return pBufMatch; // Return the Matched Buffer!
}
FF_ERROR FF_FormatPartition(FF_IOMAN *pIoman, FF_T_UINT32 ulPartitionNumber, FF_T_UINT32 ulClusterSize) {
FF_BUFFER *pBuffer;
FF_T_SINT8 scPartitionCount;
FF_T_UINT32 maxClusters, f16MaxClusters, f32MaxClusters;
FF_T_UINT32 fatSize = 32; // Default to a fat32 format.
FF_PARTITION_ENTRY partitionGeom;
FF_T_UINT32 ulBPRLba; ///< The LBA of the boot partition record.
FF_T_UINT32 fat32Size, fat16Size, newFat32Size, newFat16Size, finalFatSize;
FF_T_UINT32 sectorsPerCluster = ulClusterSize / pIoman->BlkSize;
FF_T_UINT32 ulReservedSectors, ulTotalSectors;
FF_T_UINT32 ul32DataSectors, ul16DataSectors;
FF_T_UINT32 i;
FF_T_UINT32 ulClusterBeginLBA;
FF_ERROR Error = FF_ERR_NONE;
// Get Partition Metrics, and pass on to FF_Format() function
pBuffer = FF_GetBuffer(pIoman, 0, FF_MODE_READ);
{
if(!pBuffer) {
return FF_ERR_DEVICE_DRIVER_FAILED | FF_FORMATPARTITION;
}
scPartitionCount = FF_PartitionCount(pBuffer->pBuffer);
if(!scPartitionCount) {
// Get Partition Geom from volume boot record.
ulBPRLba = 0;
partitionGeom.ulStartLBA = FF_getShort(pBuffer->pBuffer, FF_FAT_RESERVED_SECTORS); // Get offset to start of where we can actually put the FAT table.
ulReservedSectors = partitionGeom.ulStartLBA;
partitionGeom.ulLength = (FF_T_UINT32) FF_getShort(pBuffer->pBuffer, FF_FAT_16_TOTAL_SECTORS);
if(partitionGeom.ulLength == 0) { // 32-bit entry was used.
partitionGeom.ulLength = FF_getLong(pBuffer->pBuffer, FF_FAT_32_TOTAL_SECTORS);
}
ulTotalSectors = partitionGeom.ulLength;
partitionGeom.ulLength -= partitionGeom.ulStartLBA; // Remove the reserved sectors from the count.
} else {
// Get partition Geom from the partition table entry.
}
// Calculate the max possiblenumber of clusters based on clustersize.
maxClusters = partitionGeom.ulLength / sectorsPerCluster;
// Determine the size of a FAT table required to support this.
fat32Size = (maxClusters * 4) / pIoman->BlkSize; // Potential size in sectors of a fat32 table.
if((maxClusters * 4) % pIoman->BlkSize) {
fat32Size++;
}
fat32Size *= 2; // Officially there are 2 copies of the FAT.
fat16Size = (maxClusters * 2) / pIoman->BlkSize; // Potential size in bytes of a fat16 table.
if((maxClusters * 2) % pIoman->BlkSize) {
fat16Size++;
}
fat16Size *= 2;
// A real number of sectors to be available is therefore ~~
ul16DataSectors = partitionGeom.ulLength - fat16Size;
ul32DataSectors = partitionGeom.ulLength - fat32Size;
f16MaxClusters = ul16DataSectors / sectorsPerCluster;
f32MaxClusters = ul32DataSectors / sectorsPerCluster;
newFat16Size = (f16MaxClusters * 2) / pIoman->BlkSize;
if((f16MaxClusters * 2) % pIoman->BlkSize) {
newFat16Size++;
}
newFat32Size = (f32MaxClusters * 4) / pIoman->BlkSize;
if((f32MaxClusters * 4) % pIoman->BlkSize) {
newFat32Size++;
}
// Now determine if this should be fat16/32 format?
if(f16MaxClusters < 65525) {
fatSize = 16;
finalFatSize = newFat16Size;
} else {
fatSize = 32;
finalFatSize = newFat32Size;
}
FF_ReleaseBuffer(pIoman, pBuffer);
for(i = 0; i < finalFatSize*2; i++) { // Ensure the FAT table is clear.
if(i == 0) {
pBuffer = FF_GetBuffer(pIoman, partitionGeom.ulStartLBA, FF_MODE_WR_ONLY);
if(!pBuffer) {
return FF_ERR_DEVICE_DRIVER_FAILED;
}
memset(pBuffer->pBuffer, 0, pIoman->BlkSize);
} else {
FF_BlockWrite(pIoman, partitionGeom.ulStartLBA+i, 1, pBuffer->pBuffer, FF_FALSE);
}
}
switch(fatSize) {
case 16: {
FF_putShort(pBuffer->pBuffer, 0, 0xFFF8); // First FAT entry.
FF_putShort(pBuffer->pBuffer, 2, 0xFFFF); // RESERVED alloc.
break;
}
case 32: {
FF_putLong(pBuffer->pBuffer, 0, 0x0FFFFFF8); // FAT32 FAT sig.
FF_putLong(pBuffer->pBuffer, 4, 0xFFFFFFFF); // RESERVED alloc.
FF_putLong(pBuffer->pBuffer, 8, 0x0FFFFFFF); // Root dir allocation.
break;
}
default:
break;
}
FF_ReleaseBuffer(pIoman, pBuffer);
// Clear and initialise the root dir.
ulClusterBeginLBA = partitionGeom.ulStartLBA + (finalFatSize*2);
for(i = 0; i < sectorsPerCluster; i++) {
if(i == 0) {
pBuffer = FF_GetBuffer(pIoman, ulClusterBeginLBA, FF_MODE_WR_ONLY);
memset(pBuffer->pBuffer, 0, pIoman->BlkSize);
} else {
FF_BlockWrite(pIoman, ulClusterBeginLBA+i, 1, pBuffer->pBuffer, FF_FALSE);
}
}
FF_ReleaseBuffer(pIoman, pBuffer);
// Correctly modify the second FAT item again.
pBuffer = FF_GetBuffer(pIoman, partitionGeom.ulStartLBA + finalFatSize, FF_MODE_WRITE);
{
switch(fatSize) {
case 16: {
FF_putShort(pBuffer->pBuffer, 0, 0xFFF8);
FF_putShort(pBuffer->pBuffer, 2, 0xFFFF);
break;
}
case 32:
FF_putLong(pBuffer->pBuffer, 0, 0x0FFFFFF8);
FF_putLong(pBuffer->pBuffer, 4, 0xFFFFFFFF);
FF_putLong(pBuffer->pBuffer, 8, 0x0FFFFFFF); // Root dir allocation.
}
}
FF_ReleaseBuffer(pIoman, pBuffer);
// Modify the fields in the VBR/PBR for correct mounting.
pBuffer = FF_GetBuffer(pIoman, ulBPRLba, FF_MODE_WRITE); // Modify the FAT descriptions.
{
// -- First section Common vars to Fat12/16 and 32.
memset(pBuffer->pBuffer, 0, pIoman->BlkSize); // Clear the boot record.
FF_putChar(pBuffer->pBuffer, 0, 0xEB); // Place the Jump to bootstrap x86 instruction.
FF_putChar(pBuffer->pBuffer, 1, 0x3C); // Even though we won't populate the bootstrap code.
FF_putChar(pBuffer->pBuffer, 2, 0x90); // Some devices look for this as a signature.
memcpy(((FF_T_UINT8 *)pBuffer->pBuffer+3), "FULLFAT2", 8); // Place the FullFAT OEM code.
FF_putShort(pBuffer->pBuffer, 11, pIoman->BlkSize);
FF_putChar(pBuffer->pBuffer, 13, (FF_T_UINT8) sectorsPerCluster);
FF_putShort(pBuffer->pBuffer, FF_FAT_RESERVED_SECTORS, (FF_T_UINT16)partitionGeom.ulStartLBA); // Number of reserved sectors. (1 for fat12/16, 32 for f32).
FF_putShort(pBuffer->pBuffer, FF_FAT_NUMBER_OF_FATS, 2); // Always 2 copies.
//FF_putShort(pBuffer->pBuffer, 19, 0); // Number of sectors in partition if size < 32mb.
FF_putChar(pBuffer->pBuffer, 21, 0xF8); // Media type -- HDD.
FF_putShort(pBuffer->pBuffer, 510, 0xAA55); // MBR sig.
FF_putLong(pBuffer->pBuffer, 32, partitionGeom.ulLength+partitionGeom.ulStartLBA); // Total sectors of this partition.
if(fatSize == 32) {
FF_putShort(pBuffer->pBuffer, 36, (FF_T_UINT16)finalFatSize); // Number of sectors per fat.
FF_putShort(pBuffer->pBuffer, 44, 2); // Root dir cluster (2).
FF_putShort(pBuffer->pBuffer, 48, 1); // FSINFO sector at LBA1.
FF_putShort(pBuffer->pBuffer, 50, 6); // 0 for no backup boot sector.
FF_putChar(pBuffer->pBuffer, 66, 0x29); // Indicate extended signature is present.
memcpy(((FF_T_UINT8 *)pBuffer->pBuffer+71), "FullFAT2-V", 10); // Volume name.
memcpy(((FF_T_UINT8 *)pBuffer->pBuffer+81), "FAT32 ", 8);
// Put backup boot sector.
FF_BlockWrite(pIoman, 6, 1, pBuffer->pBuffer, FF_FALSE);
} else {
FF_putChar(pBuffer->pBuffer, 38, 0x28); // Signal this contains an extended signature.
memcpy(((FF_T_UINT8 *)pBuffer->pBuffer+43), "FullFAT2-V", 10); // Volume name.
memcpy(((FF_T_UINT8 *)pBuffer->pBuffer+54), "FAT16 ", 8);
FF_putShort(pBuffer->pBuffer, FF_FAT_16_SECTORS_PER_FAT, (FF_T_UINT16) finalFatSize);
FF_putShort(pBuffer->pBuffer, 17, 512); // Number of Dir entries. (FAT32 0).
//FF_putShort(pBuffer->pBuffer, FF_FAT_ROOT_ENTRY_COUNT,
}
}
}
FF_ReleaseBuffer(pIoman, pBuffer);
if(fatSize == 32) {
// Finally if FAT32, create an FSINFO sector.
pBuffer = FF_GetBuffer(pIoman, 1, FF_MODE_WRITE);
{
memset(pBuffer->pBuffer, 0, pIoman->BlkSize);
FF_putLong(pBuffer->pBuffer, 0, 0x41615252); // FSINFO sect magic number.
FF_putLong(pBuffer->pBuffer, 484, 0x61417272); // FSINFO second sig.
// Calculate total sectors, -1 for the root dir allocation. (Free sectors count).
FF_putLong(pBuffer->pBuffer, 488, ((ulTotalSectors - (ulReservedSectors + (2*finalFatSize))) / sectorsPerCluster)-1);
FF_putLong(pBuffer->pBuffer, 492, 2); // Hint for next free cluster.
FF_putShort(pBuffer->pBuffer, 510, 0xAA55);
}
FF_ReleaseBuffer(pIoman, pBuffer);
}
FF_FlushCache(pIoman);
return Error;
}
/**
* @public
* @brief Writes data to a File.
*
* @param pFile FILE Pointer.
* @param ElementSize Size of an Element of Data to be copied. (in bytes).
* @param Count Number of Elements of Data to be copied. (ElementSize * Count must not exceed ((2^31)-1) bytes. (2GB). For best performance, multiples of 512 bytes or Cluster sizes are best.
* @param buffer Byte-wise buffer containing the data to be written.
*
* @return
**/
FF_T_SINT32 FF_Write(FF_FILE *pFile, FF_T_UINT32 ElementSize, FF_T_UINT32 Count, FF_T_UINT8 *buffer) {
FF_T_UINT32 nBytes = ElementSize * Count;
FF_T_UINT32 nBytesWritten = 0;
FF_T_UINT32 nBytesToWrite;
FF_IOMAN *pIoman;
FF_BUFFER *pBuffer;
FF_T_UINT32 nRelBlockPos;
FF_T_UINT32 nItemLBA;
FF_T_SINT32 slRetVal = 0;
FF_T_UINT16 sSectors;
FF_T_UINT32 nRelClusterPos;
FF_T_UINT32 nBytesPerCluster, nClusterDiff, nClusters;
FF_ERROR Error;
if(!pFile) {
return FF_ERR_NULL_POINTER;
}
if(!(pFile->Mode & FF_MODE_WRITE)) {
return FF_ERR_FILE_NOT_OPENED_IN_WRITE_MODE;
}
// Make sure a write is after the append point.
if((pFile->Mode & FF_MODE_APPEND)) {
if(pFile->FilePointer < pFile->Filesize) {
FF_Seek(pFile, 0, FF_SEEK_END);
}
}
pIoman = pFile->pIoman;
nBytesPerCluster = (pIoman->pPartition->SectorsPerCluster * pIoman->BlkSize);
// Extend File for atleast nBytes!
// Handle file-space allocation
Error = FF_ExtendFile(pFile, pFile->FilePointer + nBytes);
if(Error) {
return Error;
}
nRelBlockPos = FF_getMinorBlockEntry(pIoman, pFile->FilePointer, 1); // Get the position within a block.
nClusterDiff = FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1) - pFile->CurrentCluster;
if(nClusterDiff) {
if(pFile->CurrentCluster != FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1)) {
pFile->AddrCurrentCluster = FF_TraverseFAT(pIoman, pFile->AddrCurrentCluster, nClusterDiff, &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += nClusterDiff;
}
}
nItemLBA = FF_Cluster2LBA(pIoman, pFile->AddrCurrentCluster);
nItemLBA = FF_getRealLBA(pIoman, nItemLBA + FF_getMajorBlockNumber(pIoman, pFile->FilePointer, 1)) + FF_getMinorBlockNumber(pIoman, pFile->FilePointer, 1);
if((nRelBlockPos + nBytes) < pIoman->BlkSize) { // Bytes to read are within a block and less than a block size.
pBuffer = FF_GetBuffer(pIoman, nItemLBA, FF_MODE_WRITE);
{
if(!pBuffer) {
return FF_ERR_DEVICE_DRIVER_FAILED;
}
memcpy((pBuffer->pBuffer + nRelBlockPos), buffer, nBytes);
}
FF_ReleaseBuffer(pIoman, pBuffer);
pFile->FilePointer += nBytes;
nBytesWritten = nBytes;
//return nBytes; // Return the number of bytes read.
} else {
//---------- Write (memcpy) to a Sector Boundary
if(nRelBlockPos != 0) { // Not on a sector boundary, at this point the LBA is known.
nBytesToWrite = pIoman->BlkSize - nRelBlockPos;
pBuffer = FF_GetBuffer(pIoman, nItemLBA, FF_MODE_WRITE);
{
if(!pBuffer) {
return FF_ERR_DEVICE_DRIVER_FAILED;
}
// Here we copy to the sector boudary.
memcpy((pBuffer->pBuffer + nRelBlockPos), buffer, nBytesToWrite);
}
FF_ReleaseBuffer(pIoman, pBuffer);
nBytes -= nBytesToWrite;
nBytesWritten += nBytesToWrite;
pFile->FilePointer += nBytesToWrite;
buffer += nBytesToWrite;
}
//---------- Write to a Cluster Boundary
nRelClusterPos = FF_getClusterPosition(pIoman, pFile->FilePointer, 1);
if(nRelClusterPos != 0 && nBytes >= nBytesPerCluster) { // Need to get to cluster boundary
nClusterDiff = FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1) - pFile->CurrentCluster;
if(nClusterDiff) {
if(pFile->CurrentCluster < FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1)) {
pFile->AddrCurrentCluster = FF_TraverseFAT(pIoman, pFile->AddrCurrentCluster, nClusterDiff, &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += nClusterDiff;
}
}
nItemLBA = FF_Cluster2LBA(pIoman, pFile->AddrCurrentCluster);
nItemLBA = FF_getRealLBA(pIoman, nItemLBA + FF_getMajorBlockNumber(pIoman, pFile->FilePointer, 1)) + FF_getMinorBlockNumber(pIoman, pFile->FilePointer, 1);
sSectors = (FF_T_UINT16) (pIoman->pPartition->SectorsPerCluster - (nRelClusterPos / pIoman->BlkSize));
slRetVal = FF_BlockWrite(pFile->pIoman, nItemLBA, sSectors, buffer);
if(slRetVal < 0) {
return slRetVal;
}
nBytesToWrite = sSectors * pIoman->BlkSize;
nBytes -= nBytesToWrite;
buffer += nBytesToWrite;
nBytesWritten += nBytesToWrite;
pFile->FilePointer += nBytesToWrite;
}
//---------- Write Clusters
if(nBytes >= nBytesPerCluster) {
//----- Thanks to Christopher Clark of DigiPen Institute of Technology in Redmond, US adding this traversal check.
nClusterDiff = FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1) - pFile->CurrentCluster;
if(nClusterDiff) {
if(pFile->CurrentCluster < FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1)) {
pFile->AddrCurrentCluster = FF_TraverseFAT(pIoman, pFile->AddrCurrentCluster, nClusterDiff, &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += nClusterDiff;
}
}
//----- End of Contributor fix.
nClusters = (nBytes / nBytesPerCluster);
slRetVal = FF_WriteClusters(pFile, nClusters, buffer);
if(slRetVal < 0) {
return slRetVal;
}
nBytesToWrite = (nBytesPerCluster * nClusters);
pFile->FilePointer += nBytesToWrite;
nBytes -= nBytesToWrite;
buffer += nBytesToWrite;
nBytesWritten += nBytesToWrite;
}
//---------- Write Remaining Blocks
if(nBytes >= pIoman->BlkSize) {
sSectors = (FF_T_UINT16) (nBytes / pIoman->BlkSize);
nClusterDiff = FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1) - pFile->CurrentCluster;
if(nClusterDiff) {
if(pFile->CurrentCluster < FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1)) {
pFile->AddrCurrentCluster = FF_TraverseFAT(pIoman, pFile->AddrCurrentCluster, nClusterDiff, &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += nClusterDiff;
}
}
nItemLBA = FF_Cluster2LBA(pIoman, pFile->AddrCurrentCluster);
nItemLBA = FF_getRealLBA(pIoman, nItemLBA + FF_getMajorBlockNumber(pIoman, pFile->FilePointer, 1)) + FF_getMinorBlockNumber(pIoman, pFile->FilePointer, 1);
slRetVal = FF_BlockWrite(pFile->pIoman, nItemLBA, sSectors, buffer);
if(slRetVal < 0) {
return slRetVal;
}
nBytesToWrite = sSectors * pIoman->BlkSize;
pFile->FilePointer += nBytesToWrite;
nBytes -= nBytesToWrite;
buffer += nBytesToWrite;
nBytesWritten += nBytesToWrite;
}
//---------- Write (memcpy) Remaining Bytes
if(nBytes > 0) {
nClusterDiff = FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1) - pFile->CurrentCluster;
if(nClusterDiff) {
if(pFile->CurrentCluster < FF_getClusterChainNumber(pFile->pIoman, pFile->FilePointer, 1)) {
pFile->AddrCurrentCluster = FF_TraverseFAT(pIoman, pFile->AddrCurrentCluster, nClusterDiff, &Error);
if(Error) {
return Error;
}
pFile->CurrentCluster += nClusterDiff;
}
}
nItemLBA = FF_Cluster2LBA(pIoman, pFile->AddrCurrentCluster);
nItemLBA = FF_getRealLBA(pIoman, nItemLBA + FF_getMajorBlockNumber(pIoman, pFile->FilePointer, 1)) + FF_getMinorBlockNumber(pIoman, pFile->FilePointer, 1);
pBuffer = FF_GetBuffer(pIoman, nItemLBA, FF_MODE_WRITE);
{
if(!pBuffer) {
return FF_ERR_DEVICE_DRIVER_FAILED;
}
memcpy(pBuffer->pBuffer, buffer, nBytes);
}
FF_ReleaseBuffer(pIoman, pBuffer);
nBytesToWrite = nBytes;
pFile->FilePointer += nBytesToWrite;
nBytes -= nBytesToWrite;
buffer += nBytesToWrite;
nBytesWritten += nBytesToWrite;
}
}
if(pFile->FilePointer > pFile->Filesize) {
pFile->Filesize = pFile->FilePointer;
}
return nBytesWritten;
}
