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1 /* basicmbr.h -- MBR data structure definitions, types, and functions */
2 
3 /* This program is copyright (c) 2009-2013 by Roderick W. Smith. It is distributed
4   under the terms of the GNU GPL version 2, as detailed in the COPYING file. */
5 
6 #include <stdint.h>
7 #include <sys/types.h>
8 #include "diskio.h"
9 #include "mbrpart.h"
10 
11 #ifndef __BASICMBRSTRUCTS
12 #define __BASICMBRSTRUCTS
13 
14 #define MBR_SIGNATURE UINT16_C(0xAA55)
15 
16 // Maximum number of MBR partitions
17 #define MAX_MBR_PARTS 128
18 
19 using namespace std;
20 
21 /****************************************
22  *                                      *
23  * MBRData class and related structures *
24  *                                      *
25  ****************************************/
26 
27 // A 512-byte data structure into which the MBR can be loaded in one
28 // go. Also used when loading logical partitions.
29 #pragma pack(1)
30 struct TempMBR {
31    uint8_t code[440];
32    uint32_t diskSignature;
33    uint16_t nulls;
34    struct MBRRecord partitions[4];
35    uint16_t MBRSignature;
36 }; // struct TempMBR
37 
38 // Possible states of the MBR
39 enum MBRValidity {invalid, gpt, hybrid, mbr};
40 
41 // Full data in tweaked MBR format
42 class BasicMBRData {
43 protected:
44    uint8_t code[440];
45    uint32_t diskSignature;
46    uint16_t nulls;
47    // MAX_MBR_PARTS defaults to 128. This array holds both the primary and
48    // the logical partitions, to simplify data retrieval for GPT conversions.
49    MBRPart partitions[MAX_MBR_PARTS];
50    uint16_t MBRSignature;
51 
52    // Above are basic MBR data; now add more stuff....
53    uint32_t blockSize; // block size (usually 512)
54    uint64_t diskSize; // size in blocks
55    uint32_t numHeads; // number of heads, in CHS scheme
56    uint32_t numSecspTrack; // number of sectors per track, in CHS scheme
57    DiskIO* myDisk;
58    int canDeleteMyDisk;
59    string device;
60    MBRValidity state;
61    MBRPart* GetPartition(int i); // Return primary or logical partition
62 public:
63    BasicMBRData(void);
64    BasicMBRData(string deviceFilename);
65    ~BasicMBRData(void);
66    BasicMBRData & operator=(const BasicMBRData & orig);
67 
68    // File I/O functions...
69    int ReadMBRData(const string & deviceFilename);
70    int ReadMBRData(DiskIO * theDisk, int checkBlockSize = 1);
71    int ReadLogicalParts(uint64_t extendedStart, int partNum);
72    int WriteMBRData(void);
73    int WriteMBRData(DiskIO *theDisk);
74    int WriteMBRData(const string & deviceFilename);
75    int WriteMBRData(struct TempMBR & mbr, DiskIO *theDisk, uint64_t sector);
DiskSync(void)76    void DiskSync(void) {myDisk->DiskSync();}
77    void SetDisk(DiskIO *theDisk);
78 
79    // Display data for user...
80    void DisplayMBRData(void);
81    void ShowState(void);
82 
83    // GPT checks and fixes...
84    int CheckForGPT(void);
85    int BlankGPTData(void);
86 
87    // Functions that set or get disk metadata (size, CHS geometry, etc.)
SetDiskSize(uint64_t ds)88    void SetDiskSize(uint64_t ds) {diskSize = ds;}
SetBlockSize(uint32_t bs)89    void SetBlockSize(uint32_t bs) {blockSize = bs;}
GetValidity(void)90    MBRValidity GetValidity(void) {return state;}
SetHybrid(void)91    void SetHybrid(void) {state = hybrid;} // Set hybrid flag
92    void ReadCHSGeom(void);
93    int GetPartRange(uint32_t* low, uint32_t* high);
94    int LBAtoCHS(uint64_t lba, uint8_t * chs); // Convert LBA to CHS
95    int FindOverlaps(void);
96    int NumPrimaries(void);
97    int NumLogicals(void);
98    int CountParts(void);
99    void UpdateCanBeLogical(void);
100    uint64_t FirstLogicalLBA(void);
101    uint64_t LastLogicalLBA(void);
102    int AreLogicalsContiguous(void);
103    int DoTheyFit(void);
104    int SpaceBeforeAllLogicals(void);
105    int IsLegal(void);
106    int IsEEActive(void);
107    int FindNextInUse(int start);
108 
109    // Functions to create, delete, or change partitions
110    // Pass EmptyMBR 1 to clear the boot loader code, 0 to leave it intact
111    void EmptyMBR(int clearBootloader = 1);
112    void EmptyBootloader(void);
113    void AddPart(int num, const MBRPart& newPart);
114    void MakePart(int num, uint64_t startLBA, uint64_t lengthLBA, int type = 0x07,
115                  int bootable = 0);
116    int SetPartType(int num, int type);
117    int SetPartBootable(int num, int bootable = 1);
118    int MakeBiggestPart(int i, int type); // Make partition filling most space
119    void DeletePartition(int i);
120    int SetInclusionwChecks(int num, int inclStatus);
121    void RecomputeCHS(int partNum);
122    void SortMBR(int start = 0);
123    int DeleteOversizedParts();
124    int DeleteExtendedParts();
125    void OmitOverlaps(void);
126    void MaximizeLogicals();
127    void MaximizePrimaries();
128    void TrimPrimaries();
129    void MakeLogicalsContiguous(void);
130    void MakeItLegal(void);
131    int RemoveLogicalsFromFirstFour(void);
132    int MovePrimariesToFirstFour(void);
133    int CreateExtended(void);
134 
135    // Functions to find information on free space....
136    uint64_t FindFirstAvailable(uint64_t start = 1);
137    uint64_t FindLastInFree(uint64_t start);
138    uint64_t FindFirstInFree(uint64_t start);
139    int SectorUsedAs(uint64_t sector, int topPartNum = MAX_MBR_PARTS);
140 
141    // Functions to extract data on specific partitions....
142    uint8_t GetStatus(int i);
143    uint8_t GetType(int i);
144    uint64_t GetFirstSector(int i);
145    uint64_t GetLength(int i);
146 
147    // User interaction functions....
148    int DoMenu(const string& prompt = "\nMBR command (? for help): ");
149    void ShowCommands(void);
150 }; // class BasicMBRData
151 
152 #endif
153