initial import

1 files changed, 83 insertions, 0 deletions

diff --git a/inc/bpb.h b/inc/bpb.h
new file mode 100644
index 0000000..8df04a1
--- /dev/null
+++ b/inc/bpb.h
@@ -0,0 +1,83 @@
+#ifndef BPB_H
+#define BPB_H
+
+#include <stdint.h>
+#include "sassert.h"
+
+#define DOS_BPB_OFFSET_ON_DISK 0x0B
+
+typedef _Packed struct DOS_BPB_DOS3
+{
+	/** Number of bytes per sector. */
+	uint16_t bytesPerSector;
+	/** Number of sectors per cluster. Must be power of 2. */
+	uint8_t sectorsPerCluster;
+	/** Number of reserved sectors. */
+	uint16_t reservedSectors;
+	/** Number of FATs. */
+	uint8_t numberOfFATs;
+	/** Maximum number of entries in the root directory. */
+	uint16_t rootDirEntries;
+	/** Total number of sectors on the drive. If drive larger than 32MB, this field is zero, see numberOfSectorsLarge. */
+	uint16_t numberOfSectors;
+	/** Media descriptor byte. */
+	uint8_t mediaType;
+	/** Number of sectors used by a FAT. */
+	uint16_t sectorsPerFAT;
+	/** Number of sectors per track. */
+	uint16_t sectorsPerTrack;
+	/** Number of heads. */
+	uint16_t numberOfHeads;
+	/** Number of hidden sectors on the drive, from the start of the drive. */
+	uint32_t hiddenSectors;
+	/** Number of sectors, only used if drive > 32MB. */
+	uint32_t numberOfSectorsLarge;
+} DOS_BPB_DOS3;
+STATIC_ASSERT(sizeof(DOS_BPB_DOS3) == 25);
+
+typedef _Packed struct DOS_BPB_DOS4
+{
+	struct DOS_BPB_DOS3;
+	uint8_t physicalDriveNumber;
+	uint8_t flags;
+	uint8_t extendedBootSignature;
+	uint32_t volumeSerialNumber;
+	char volumeLabel[11];
+	char fsType[8];
+} DOS_BPB_DOS4;
+STATIC_ASSERT(sizeof(DOS_BPB_DOS4) == 25 + 26);
+
+typedef _Packed struct DOS_BPB_FAT32
+{
+	struct DOS_BPB_DOS3;
+	uint32_t sectorPerFatLarge;
+	uint16_t extendedFlags;
+	uint16_t version;
+	uint32_t rootDirCluster;
+	uint16_t infoSector;
+	uint16_t backupBootSector;
+
+	char bootFileName[12];
+	uint8_t physicalDriveNumber;
+	uint8_t flags;
+	uint8_t extendedBootSignature;
+	uint32_t volumeSerialNumber;
+	char volumeLabel[11];
+	char fsType[8];
+} DOS_BPB_FAT32;
+STATIC_ASSERT(sizeof(DOS_BPB_FAT32) == 25 + 54);
+
+/** Union of all BPB types. Default is DOS4 / FAT16. */
+typedef union DOS_BPB
+{
+	struct DOS_BPB_DOS3;
+	struct DOS_BPB_DOS4  fat16;
+	struct DOS_BPB_FAT32 fat32;
+} DOS_BPB;
+
+typedef enum DOS_BPB_MEDIA_TYPE
+{
+	DOS_BPB_MEDIA_HDD = 0xF8
+} DOS_BPB_MEDIA_TYPE;
+
+#endif // BPB_H