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Fix computation of total data clusters and free clusters #42

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Fix computation of total data clusters and free clusters #42

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9 changes: 6 additions & 3 deletions src/core/FatSystem.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -160,7 +160,7 @@ void FatSystem::parseHeader()
(rootEntries*FAT_ENTRY_SIZE + bytesPerSector-1)/bytesPerSector;
unsigned long dataSectors = totalSectors -
(reservedSectors + fats*sectorsPerFat + rootDirSectors);
unsigned long totalClusters = dataSectors/sectorsPerCluster;
totalClusters = dataSectors/sectorsPerCluster;
bits = (totalClusters > MAX_FAT12) ? 16 : 12;
} else {
type = FAT32;
Expand All @@ -170,6 +170,9 @@ void FatSystem::parseHeader()
diskLabel = string(buffer+FAT_DISK_LABEL, FAT_DISK_LABEL_SIZE);
rootDirectory = FAT_READ_LONG(buffer, FAT_ROOT_DIRECTORY)&0xffffffff;
fsType = string(buffer+FAT_DISK_FS, FAT_DISK_FS_SIZE);
unsigned long dataSectors = totalSectors -
(reservedSectors + fats*sectorsPerFat);
totalClusters = dataSectors/sectorsPerCluster;
}

if (bytesPerSector != 512) {
Expand Down Expand Up @@ -663,7 +666,7 @@ bool FatSystem::init()
bytesPerCluster = bytesPerSector*sectorsPerCluster;
totalSize = totalSectors*bytesPerSector;
fatSize = sectorsPerFat*bytesPerSector;
totalClusters = (fatSize*8)/bits;
// totalClusters = (fatSize*8)/bits;
dataSize = totalClusters*bytesPerCluster;

if (type == FAT16) {
Expand Down Expand Up @@ -860,7 +863,7 @@ void FatSystem::computeStats()

freeClusters = 0;
for (unsigned int cluster=0; cluster<totalClusters; cluster++) {
if (freeCluster(cluster)) {
if (freeCluster(cluster + 2)) {
freeClusters++;
}
}
Expand Down