CopyHFSMeta/Data.h

   1 #ifndef _DATA_H
   2 # define _DATA_H
   3
   4 # include <errno.h>
   5 /*
   6  * Exit status values.  We use some errno values because
   7  * they are convenient.
   8  * kGoodExit:  we finished copying, and no problems.
   9  * kNoSpaceExit:  Not enough space for the skeleton copy.
  10  * kCopyIOExit:  An I/O error occurred.  This may not be fatal,
  11  *      as it may just mean the source device went away.  We
  12  *      can continue later, perhaps.
  13  * kIntrExit:  The copying was interrupted.  As above, this may
  14  *      not be fatal.
  15  * kBadExit:  Any other problem.
  16  */
  17 enum {
  18         kGoodExit = 0,
  19         kNoSpaceExit = ENOSPC,
  20         kCopyIOExit = EIO,
  21         kIntrExit = EINTR,
  22         kBadExit = 1,
  23 };
  24
  25 /*
  26  * Data-manipulating functions and structures, used to
  27  * create the skeleton copy.
  28  */
  29 struct DeviceInfo;
  30 struct VolumeDescriptor;
  31 struct IOWrapper;
  32
  33 /*
  34  * We treat each data structure in the filesystem as
  35  * a <start, length> pair.
  36  */
  37 struct Extents {
  38         off_t base;
  39         off_t length;
  40         unsigned int fid;       // Optional, may not be set
  41 };
  42 typedef struct Extents Extents_t;
  43
  44 #define kExtentCount    100
  45
  46 /*
  47  * The in-core representation consists of a linked
  48  * list of an array of extents, up to 100 in each element.
  49  */
  50 struct ExtentList {
  51         size_t count;
  52         Extents_t extents[kExtentCount];
  53         struct ExtentList *next;
  54 };
  55 typedef struct ExtentList ExtentList_t;
  56 /*
  57  * The in-core description of the volume:  an input source,
  58  * a description of the volume, the linked list of extents,
  59  * the total number of bytes, and the number of linked list
  60  * elements.
  61  */
  62 struct VolumeObjects {
  63         struct DeviceInfo *devp;
  64         struct VolumeDescriptor *vdp;
  65         size_t count;
  66         off_t byteCount;
  67         ExtentList_t *list;
  68 };
  69 typedef struct VolumeObjects VolumeObjects_t;
  70
  71 typedef int (^extent_handler_t)(int fid, off_t start, off_t len);
  72
  73 extern VolumeObjects_t *InitVolumeObject(struct DeviceInfo *devp, struct VolumeDescriptor *vdp);
  74 extern int AddExtent(VolumeObjects_t *vop, off_t start, off_t length);
  75 extern int AddExtentForFile(VolumeObjects_t *vop, off_t start, off_t length, unsigned int fid);
  76 extern void PrintVolumeObject(VolumeObjects_t*);
  77 extern int CopyObjectsToDest(VolumeObjects_t*, struct IOWrapper *wrapper, off_t skip);
  78
  79 extern void WriteGatheredData(const char *, VolumeObjects_t*);
  80
  81 extern struct DeviceInfo *OpenDevice(const char *, int);
  82 extern struct VolumeDescriptor *VolumeInfo(struct DeviceInfo *);
  83 extern int AddHeaders(VolumeObjects_t *, int);
  84 extern void AddJournal(VolumeObjects_t *);
  85 extern void AddFileExtents(VolumeObjects_t *);
  86 extern int FindOtherMetadata(VolumeObjects_t *, extent_handler_t);
  87 extern int CompareVolumeHeaders(struct VolumeDescriptor*);
  88
  89 void ReleaseDeviceInfo(struct DeviceInfo *);
  90 void ReleaseVolumeDescriptor(struct VolumeDescriptor*);
  91 void ReleaseVolumeObjects(VolumeObjects_t *);
  92 #endif /* _DATA_H */