/* ****************************************************************************
* esint8 dir_addCluster(FileSystem *fs,euint32 firstCluster)
* This function extends a directory by 1 cluster + optional the number of
* clusters you want pre-allocated. It will also delete the contents of that
* cluster. (or clusters)
* Return value: 0 on success, -1 on fail
*/
esint8 dir_addCluster(FileSystem *fs,euint32 firstCluster)
{
euint32 lastc,logicalc;
ClusterChain cache;
fs_initClusterChain(fs,&cache,firstCluster);
if(fat_allocClusterChain(fs,&cache,1)) {
return(-1);
}
lastc = fs_getLastCluster(fs,&cache);
if(CLUSTER_PREALLOC_DIRECTORY) {
if(fat_allocClusterChain(fs,&cache,CLUSTER_PREALLOC_DIRECTORY)) {
return(-1);
}
logicalc = fat_DiscToLogicCluster(fs,firstCluster,lastc);
while(!fat_LogicToDiscCluster(fs,&cache,++logicalc)) {
fs_clearCluster(fs,cache.DiscCluster);
}
} else {
fs_clearCluster(fs,lastc);
}
return(0);
}
/* ****************************************************************************
* euint32 file_fwrite(File* file,euint32 offset,euint32 size,euint8* buf)
* Description: This function writes to a file, at offset 'offset' and size 'size'.
* It also updates the FileSize in the object, and discstructure.
* Return value: Bytes actually written.
*/
euint32 file_fwrite(File* file,euint32 offset,euint32 size,euint8* buf)
{
euint32 need_cluster;
euint32 cclus,csec,cbyte;
euint32 size_left=size,bytes_written=0;
euint32 rclus,rsec;
euint32 coffset=offset;
euint16 btr;
euint8 *tbuf;
if(!file_getAttr(file,FILE_STATUS_OPEN) || !file_getAttr(file,FILE_STATUS_WRITE))return(0);
if(offset>file->FileSize){
offset=file->FileSize;
}
need_cluster = file_requiredCluster(file,offset,size);
if(need_cluster){
if(fat_allocClusterChain(file->fs,&(file->Cache),need_cluster+CLUSTER_PREALLOC_FILE)!=0){
return(0);
}
}
while(size_left>0){
cclus = coffset/(512*file->fs->volumeId.SectorsPerCluster);
csec = (coffset/(512))%file->fs->volumeId.SectorsPerCluster;
cbyte = coffset%512;
if(cbyte!=0 || size_left<512){
btr = 512-(coffset%512)>=size_left?size_left:512-(coffset%512);
}else{
btr = 512;
}
if((fat_LogicToDiscCluster(file->fs,&(file->Cache),cclus))!=0){
file->FileSize+=bytes_written;
dir_setFileSize(file->fs,&(file->Location),file->FileSize);
return(bytes_written);
}
rclus=file->Cache.DiscCluster;
rsec=fs_clusterToSector(file->fs,rclus);
if(btr==512){
/*part_writeBuf(file->fs->part,rsec+csec,buf+bytes_written);*/
part_directSectorWrite(file->fs->part,rsec+csec,buf+bytes_written);
}else{
/*part_readBuf(file->fs->part,rsec+csec,tbuf);*/
tbuf = part_getSect(file->fs->part,rsec+csec,IOM_MODE_READWRITE);
memCpy(buf+bytes_written,tbuf+(coffset%512),btr);
/*part_writeBuf(file->fs->part,rsec+csec,tbuf);*/
part_relSect(file->fs->part,tbuf);
}
coffset+=btr;
bytes_written+=btr;
size_left-=btr;
}
if(bytes_written>file->FileSize-offset){
file->FileSize+=bytes_written-(file->FileSize-offset);
}
return(bytes_written);
}