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/* bsd.h -- BSD disklabel data structure definitions, types, and functions */
/* This program is copyright (c) 2009 by Roderick W. Smith. It is distributed
under the terms of the GNU GPL version 2, as detailed in the COPYING file. */
#include <stdint.h>
#include <sys/types.h>
#include "gptpart.h"
#include "diskio.h"
#ifndef __BSD_STRUCTS
#define __BSD_STRUCTS
#define BSD_SIGNATURE UINT32_C(0x82564557) /* BSD disklabel signature ("magic") */
// BSD disklabels can start at offsets of 64 or the sector size -- at least,
// I *THINK* that's what's going on. I've seen them at 64 or 512 on disks
// with 512-byte blocks and at 2048 on disks with 2048-byte blocks. The
// LABEL_OFFSET2 value will be replaced by the block size in the
// ReadBSDData() function....
#define LABEL_OFFSET1 64
#define LABEL_OFFSET2 512
#define NUM_OFFSETS 2
// FreeBSD documents a maximum # of partitions of 8, but I saw 16 on a NetBSD
// disk. I'm quadrupling that for further safety. Note that BSDReadData()
// uses a 4096-byte I/O buffer. In combination with LABEL_OFFSET3 and the
// additional 148-byte offset to the actual partition data, that gives a
// theoretical maximum of 118.75 partitions that the program can handle before
// memory errors will occur.
#define MAX_BSD_PARTS 64
using namespace std;
/****************************************
* *
* BSDData class and related structures *
* *
****************************************/
// Possible states of the MBR
enum BSDValidity {unknown, bsd_invalid, bsd};
// Data for a single BSD partition record
// Create entries for all fields, although we only use lengthLBA, firstLBA,
// and fsType, to simplify loading the data from disk....
struct BSDRecord { // the partition table
uint32_t lengthLBA; // number of sectors in partition
uint32_t firstLBA; // starting sector
uint32_t fragSize; // filesystem basic fragment size
uint8_t fsType; // filesystem type, see below
uint8_t frag; // filesystem fragments per block
uint16_t pcpg; // filesystem cylinders per group
};
// Full data in tweaked BSD format
// For some reason this has to be packed or MS Visual C++'s debugger complains
// about memory errors whenever a BSDData variable is destroyed.
#pragma pack (8)
class BSDData {
protected:
// We only need a few items from the main BSD disklabel data structure....
uint32_t signature; // the magic number
uint32_t sectorSize; // # of bytes per sector
uint32_t signature2; // the magic number (again)
uint16_t numParts; // number of partitions in table
struct BSDRecord* partitions; // partition array
// Above are basic BSD disklabel data; now add more stuff....
uint64_t labelFirstLBA; // first sector of BSD disklabel (partition or disk)
uint64_t labelLastLBA; // final sector of BSD disklabel
uint64_t labelStart; // BSD disklabel start point in bytes from labelFirstLBA
BSDValidity state;
public:
BSDData(void);
~BSDData(void);
int ReadBSDData(const string & deviceFilename, uint64_t startSector, uint64_t endSector);
int ReadBSDData(DiskIO *myDisk, uint64_t startSector, uint64_t endSector);
void ReverseMetaBytes(void);
void DisplayBSDData(void);
int ShowState(void); // returns 1 if BSD disklabel detected
int IsDisklabel(void);
// Functions to extract data on specific partitions....
uint8_t GetType(int i);
uint64_t GetFirstSector(int i);
uint64_t GetLength(int i);
int GetNumParts(void);
GPTPart AsGPT(int i); // Return BSD part. as GPT part.
}; // struct MBRData
#pragma pack ()
#endif