db/mork/src/orkinFile.h

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  37
  38 #ifndef _ORKINTABLE_
  39 #define _ORKINTABLE_ 1
  40
  41 #ifndef _MDB_
  42 #include "mdb.h"
  43 #endif
  44
  45 #ifndef _MORK_
  46 #include "mork.h"
  47 #endif
  48
  49 #ifndef _MORKNODE_
  50 #include "morkNode.h"
  51 #endif
  52
  53 #ifndef _MORKHANDLE_
  54 #include "morkHandle.h"
  55 #endif
  56
  57 #ifndef _MORKFILE_
  58 #include "morkFile.h"
  59 #endif
  60
  61 //3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
  62
  63 #define morkMagic_kFile 0x46696C65 /* ascii 'File' */
  64
  65 /*| orkinFile:
  66 |*/
  67 class orkinFile : public morkHandle, public nsIMdbFile { // nsIMdbFile
  68
  69 // { ===== begin morkNode interface =====
  70 public: // morkNode virtual methods
  71   // virtual void CloseMorkNode(morkEnv* ev); // morkHandle is fine
  72   virtual ~orkinFile(); // morkHandle destructor does everything
  73
  74 protected: // construction is protected (use the static Make() method)
  75   orkinFile(morkEnv* ev, // note morkUsage is always morkUsage_kPool
  76     morkHandleFace* ioFace,    // must not be nil, cookie for this handle
  77     morkFile* ioObject); // must not be nil, the object for this handle
  78
  79   // void CloseHandle(morkEnv* ev); // don't need to specialize closing
  80
  81 private: // copying is not allowed
  82   orkinFile(const morkHandle& other);
  83   orkinFile& operator=(const morkHandle& other);
  84
  85 // public: // dynamic type identification
  86   // mork_bool IsHandle() const //
  87   // { return IsNode() && mNode_Derived == morkDerived_kHandle; }
  88 // } ===== end morkNode methods =====
  89
  90 protected: // morkHandle memory management operators
  91   void* operator new(size_t inSize, morkPool& ioPool, morkZone& ioZone, morkEnv* ev) CPP_THROW_NEW
  92   { return ioPool.NewHandle(ev, inSize, &ioZone); }
  93
  94   void* operator new(size_t inSize, morkPool& ioPool, morkEnv* ev) CPP_THROW_NEW
  95   { return ioPool.NewHandle(ev, inSize, (morkZone*) 0); }
  96
  97   void* operator new(size_t inSize, morkHandleFace* ioFace) CPP_THROW_NEW
  98   { MORK_USED_1(inSize); return ioFace; }
  99
 100
 101 public: // construction:
 102
 103   static orkinFile* MakeFile(morkEnv* ev, morkFile* ioObject);
 104
 105 public: // utilities:
 106
 107   morkEnv* CanUseFile(nsIMdbEnv* mev, mork_bool inMutable,
 108     mdb_err* outErr) const;
 109
 110 public: // type identification
 111   mork_bool IsOrkinFile() const
 112   { return mHandle_Magic == morkMagic_kFile; }
 113
 114   mork_bool IsOrkinFileHandle() const
 115   { return this->IsHandle() && this->IsOrkinFile(); }
 116
 117   NS_DECL_ISUPPORTS
 118 // { ===== begin nsIMdbObject methods =====
 119
 120   // { ----- begin attribute methods -----
 121   NS_IMETHOD IsFrozenMdbObject(nsIMdbEnv* ev, mdb_bool* outIsReadonly);
 122   // same as nsIMdbPort::GetIsPortReadonly() when this object is inside a port.
 123   // } ----- end attribute methods -----
 124
 125   // { ----- begin factory methods -----
 126   NS_IMETHOD GetMdbFactory(nsIMdbEnv* ev, nsIMdbFactory** acqFactory);
 127   // } ----- end factory methods -----
 128
 129   // { ----- begin ref counting for well-behaved cyclic graphs -----
 130   NS_IMETHOD GetWeakRefCount(nsIMdbEnv* ev, // weak refs
 131     mdb_count* outCount);
 132   NS_IMETHOD GetStrongRefCount(nsIMdbEnv* ev, // strong refs
 133     mdb_count* outCount);
 134
 135   NS_IMETHOD AddWeakRef(nsIMdbEnv* ev);
 136   NS_IMETHOD AddStrongRef(nsIMdbEnv* ev);
 137
 138   NS_IMETHOD CutWeakRef(nsIMdbEnv* ev);
 139   NS_IMETHOD CutStrongRef(nsIMdbEnv* ev);
 140
 141   NS_IMETHOD CloseMdbObject(nsIMdbEnv* ev); // called at strong refs zero
 142   NS_IMETHOD IsOpenMdbObject(nsIMdbEnv* ev, mdb_bool* outOpen);
 143   // } ----- end ref counting -----
 144
 145 // } ===== end nsIMdbObject methods =====
 146
 147 // { ===== begin nsIMdbFile methods =====
 148
 149   // { ----- begin pos methods -----
 150   NS_IMETHOD Tell(nsIMdbEnv* ev, mdb_pos* outPos);
 151   NS_IMETHOD Seek(nsIMdbEnv* ev, mdb_pos inPos);
 152   NS_IMETHOD Eof(nsIMdbEnv* ev, mdb_pos* outPos);
 153   // } ----- end pos methods -----
 154
 155   // { ----- begin read methods -----
 156   NS_IMETHOD Read(nsIMdbEnv* ev, void* outBuf, mdb_size inSize,
 157     mdb_size* outActualSize);
 158   NS_IMETHOD Get(nsIMdbEnv* ev, void* outBuf, mdb_size inSize,
 159     mdb_pos inPos, mdb_size* outActualSize);
 160   // } ----- end read methods -----
 161
 162   // { ----- begin write methods -----
 163   NS_IMETHOD  Write(nsIMdbEnv* ev, const void* inBuf, mdb_size inSize,
 164     mdb_size* outActualSize);
 165   NS_IMETHOD  Put(nsIMdbEnv* ev, const void* inBuf, mdb_size inSize,
 166     mdb_pos inPos, mdb_size* outActualSize);
 167   NS_IMETHOD  Flush(nsIMdbEnv* ev);
 168   // } ----- end attribute methods -----
 169
 170   // { ----- begin path methods -----
 171   NS_IMETHOD  Path(nsIMdbEnv* ev, mdbYarn* outFilePath);
 172   // } ----- end path methods -----
 173
 174   // { ----- begin replacement methods -----
 175   NS_IMETHOD  Steal(nsIMdbEnv* ev, nsIMdbFile* ioThief);
 176   NS_IMETHOD  Thief(nsIMdbEnv* ev, nsIMdbFile** acqThief);
 177   // } ----- end replacement methods -----
 178
 179   // { ----- begin versioning methods -----
 180   NS_IMETHOD BecomeTrunk(nsIMdbEnv* ev);
 181   // If this file is a file version branch created by calling AcquireBud(),
 182   // BecomeTrunk() causes this file's content to replace the original
 183   // file's content, typically by assuming the original file's identity.
 184   // This default implementation of BecomeTrunk() does nothing, and this
 185   // is appropriate behavior for files which are not branches, and is
 186   // also the right behavior for files returned from AcquireBud() which are
 187   // in fact the original file that has been truncated down to zero length.
 188
 189   NS_IMETHOD AcquireBud(nsIMdbEnv* ev, nsIMdbHeap* ioHeap,
 190     nsIMdbFile** acqBud); // acquired file for new version of content
 191   // AcquireBud() starts a new "branch" version of the file, empty of content,
 192   // so that a new version of the file can be written.  This new file
 193   // can later be told to BecomeTrunk() the original file, so the branch
 194   // created by budding the file will replace the original file.  Some
 195   // file subclasses might initially take the unsafe but expedient
 196   // approach of simply truncating this file down to zero length, and
 197   // then returning the same morkFile pointer as this, with an extra
 198   // reference count increment.  Note that the caller of AcquireBud() is
 199   // expected to eventually call CutStrongRef() on the returned file
 200   // in order to release the strong reference.  High quality versions
 201   // of morkFile subclasses will create entirely new files which later
 202   // are renamed to become the old file, so that better transactional
 203   // behavior is exhibited by the file, so crashes protect old files.
 204   // Note that AcquireBud() is an illegal operation on readonly files.
 205   // } ----- end versioning methods -----
 206
 207 // } ===== end nsIMdbFile methods =====
 208 };
 209
 210 //3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
 211
 212 #endif /* _ORKINTABLE_ */