| 1 | /**********************************************************************
|
|---|
| 2 | *
|
|---|
| 3 | * MFFile.cpp
|
|---|
| 4 | * Copyright (C) 2003 UNESCO
|
|---|
| 5 | *
|
|---|
| 6 | * A component of the Greenstone digital library software
|
|---|
| 7 | * from the New Zealand Digital Library Project at the
|
|---|
| 8 | * University of Waikato, New Zealand.
|
|---|
| 9 | *
|
|---|
| 10 | * This program is free software; you can redistribute it and/or modify
|
|---|
| 11 | * it under the terms of the GNU General Public License as published by
|
|---|
| 12 | * the Free Software Foundation; either version 2 of the License, or
|
|---|
| 13 | * (at your option) any later version.
|
|---|
| 14 | *
|
|---|
| 15 | * This program is distributed in the hope that it will be useful,
|
|---|
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|---|
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|---|
| 18 | * GNU General Public License for more details.
|
|---|
| 19 | *
|
|---|
| 20 | * You should have received a copy of the GNU General Public License
|
|---|
| 21 | * along with this program; if not, write to the Free Software
|
|---|
| 22 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|---|
| 23 | *
|
|---|
| 24 | *********************************************************************/
|
|---|
| 25 |
|
|---|
| 26 | ////////////////////////////////////////////////////////////
|
|---|
| 27 | // MfFile.cpp : Master file object methods using blocked I/O
|
|---|
| 28 | //
|
|---|
| 29 | ////////////////////////////////////////////////////////////
|
|---|
| 30 | #include "stdafx.h"
|
|---|
| 31 | #include "IsisDb.h"
|
|---|
| 32 | #include "Checking.h"
|
|---|
| 33 |
|
|---|
| 34 |
|
|---|
| 35 |
|
|---|
| 36 | //----------------------------------------------------------------------------------
|
|---|
| 37 | // MfFile::MfFile() :
|
|---|
| 38 | //
|
|---|
| 39 | // Constructor, makes a Masterfile object that isn't connected to a file
|
|---|
| 40 | //----------------------------------------------------------------------------------
|
|---|
| 41 | MfFile::MfFile() : BlkFile(), hdr_created_(false), nextaddr_(MFCTLLEN)
|
|---|
| 42 | {
|
|---|
| 43 | lastWrittenBlock_ = -1;
|
|---|
| 44 | }
|
|---|
| 45 |
|
|---|
| 46 | //----------------------------------------------------------------------------------
|
|---|
| 47 | // int MfFile::OpenMf(const TCHAR *fname,
|
|---|
| 48 | // FileSystem::AccessMode mode /* = FileSystem::FILE_READWRITE */)
|
|---|
| 49 | //
|
|---|
| 50 | // Opens a Masterfile object
|
|---|
| 51 | //----------------------------------------------------------------------------------
|
|---|
| 52 | int MfFile::OpenMf(const TCHAR *fname, FileSystem::AccessMode mode
|
|---|
| 53 | /* = FileSystem::FILE_READWRITE */)
|
|---|
| 54 | {
|
|---|
| 55 | TCHAR mstFileName[_MAX_PATH];
|
|---|
| 56 | _tcscpy(mstFileName, fname);
|
|---|
| 57 |
|
|---|
| 58 | if (!CFileBase::Exists(mstFileName)) {
|
|---|
| 59 | mstFileName[strlen(mstFileName) - 3] = 'M';
|
|---|
| 60 | mstFileName[strlen(mstFileName) - 2] = 'S';
|
|---|
| 61 | mstFileName[strlen(mstFileName) - 1] = 'T';
|
|---|
| 62 | }
|
|---|
| 63 |
|
|---|
| 64 | int rc;
|
|---|
| 65 | try
|
|---|
| 66 | {
|
|---|
| 67 | rc = CFileBase::Open(mstFileName, mode);
|
|---|
| 68 | hdr_created_ = true;
|
|---|
| 69 | ReadMfHdr();
|
|---|
| 70 | PrintMfHdr();
|
|---|
| 71 | Checking::CheckMfHeader(mstFileName, mfh_);
|
|---|
| 72 | }
|
|---|
| 73 | catch (CFileBaseException e)
|
|---|
| 74 | {
|
|---|
| 75 | throw CIsisDbException(ISIS_MF_OPEN_ERROR, __FILE__, __LINE__);
|
|---|
| 76 | }
|
|---|
| 77 | return rc;
|
|---|
| 78 | }
|
|---|
| 79 |
|
|---|
| 80 | //----------------------------------------------------------------------------------
|
|---|
| 81 | // int MfFile::createMf(const TCHAR *fname, int type)
|
|---|
| 82 | //
|
|---|
| 83 | // Creates a Masterfile object
|
|---|
| 84 | //----------------------------------------------------------------------------------
|
|---|
| 85 | int MfFile::CreateMf(const TCHAR *fname, int type)
|
|---|
| 86 | {
|
|---|
| 87 | return 0;
|
|---|
| 88 | }
|
|---|
| 89 |
|
|---|
| 90 | //////////////////////////////
|
|---|
| 91 | MfFile::~MfFile()
|
|---|
| 92 | {
|
|---|
| 93 | }
|
|---|
| 94 |
|
|---|
| 95 | //----------------------------------------------------------------------------------
|
|---|
| 96 | // void MfFile::ReadMfRecord(long mfb, int mfp, MfRecord &m)
|
|---|
| 97 | //
|
|---|
| 98 | // Reads the master file record beginning at address (mfb,mfp) into m
|
|---|
| 99 | //----------------------------------------------------------------------------------
|
|---|
| 100 | bool MfFile::ReadMfRecord(long mfb, int mfp, MfRecord &m)
|
|---|
| 101 | {
|
|---|
| 102 | return m.Read(*this, mfb, mfp);
|
|---|
| 103 | }
|
|---|
| 104 |
|
|---|
| 105 | //-------------------------------------------------------------------------------
|
|---|
| 106 | // void WriteMfRecord(long mfb, int mfp, MfRecord &m)
|
|---|
| 107 | //
|
|---|
| 108 | // Helper protected method, which writes the Master file record m at address
|
|---|
| 109 | // (mfb, mfp) mfb (1:MAXMFB), mfp (0: MFBLKSIZE)
|
|---|
| 110 | //-------------------------------------------------------------------------------
|
|---|
| 111 | void MfFile::WriteMfRecord(long mfb, int mfp, MfRecord &m)
|
|---|
| 112 | {
|
|---|
| 113 | m.Write(*this, mfb, mfp);
|
|---|
| 114 | }
|
|---|
| 115 |
|
|---|
| 116 |
|
|---|
| 117 | //--------------------------------------------------------------------------------
|
|---|
| 118 | // void CreateMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 119 | //
|
|---|
| 120 | // Create a new record. The MFN to be assigned is obtained from the field nxtmfn_
|
|---|
| 121 | // in the Master file header. Then addMfRecord is called for adding the record
|
|---|
| 122 | // at the end of the master file, at the position indicated by the fields
|
|---|
| 123 | // nxtmfb_/nxtmfb_. The next MFN to be assigned is updated.
|
|---|
| 124 | //
|
|---|
| 125 | //--------------------------------------------------------------------------------
|
|---|
| 126 | void MfFile::CreateMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 127 | {
|
|---|
| 128 | }
|
|---|
| 129 |
|
|---|
| 130 | void MfFile::AppendNewBlock()
|
|---|
| 131 | {
|
|---|
| 132 | }
|
|---|
| 133 |
|
|---|
| 134 | //--------------------------------------------------------------------------------
|
|---|
| 135 | // void AddMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 136 | //
|
|---|
| 137 | // Add the record at the end of the master file, at the position indicated by
|
|---|
| 138 | // the fields nxtmfb_/nxtmfp_. (nxtmfp_ is in range [1:MFBLKSIZE])
|
|---|
| 139 | // Return the address where the record was stored into mfb & mfp
|
|---|
| 140 | //--------------------------------------------------------------------------------
|
|---|
| 141 | void MfFile::AddMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 142 | {
|
|---|
| 143 | }
|
|---|
| 144 |
|
|---|
| 145 |
|
|---|
| 146 | //--------------------------------------------------------------------------------
|
|---|
| 147 | // void UpdateMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 148 | //
|
|---|
| 149 | // Update a Master file record.If possible, i.e. if the record length was not
|
|---|
| 150 | // increased, the record is written back at its original location otherwise it is
|
|---|
| 151 | // written at the end of the file. In both cases, MFBWB/MFBWP are not changed.
|
|---|
| 152 | //
|
|---|
| 153 | //--------------------------------------------------------------------------------
|
|---|
| 154 | void MfFile::UpdateMfRecord(MfRecord &m, long &mfb, int &mfp)
|
|---|
| 155 | {
|
|---|
| 156 | }
|
|---|
| 157 |
|
|---|
| 158 |
|
|---|
| 159 | /////////////////////////////////////////////////////////////////////////////////////
|
|---|
| 160 | // methods for dumping file and record headers
|
|---|
| 161 |
|
|---|
| 162 |
|
|---|
| 163 | void MfFile::PrintMfHdr(SMfHeader &h)
|
|---|
| 164 | // Prints header record
|
|---|
| 165 | {
|
|---|
| 166 | }
|
|---|
| 167 |
|
|---|
| 168 | //////////////////////////////
|
|---|
| 169 |
|
|---|
| 170 | void MfFile::PrintMfRecord(MfRecord &m)
|
|---|
| 171 | // Print a master file record structure
|
|---|
| 172 | {
|
|---|
| 173 | m.Dump();
|
|---|
| 174 | }
|
|---|
| 175 |
|
|---|
| 176 | /////////////////////////////////////////////////////////////////////////////////////
|
|---|
| 177 | // Methods for accessing records directly
|
|---|
| 178 |
|
|---|
| 179 | //----------------------------------------------------------------------------------
|
|---|
| 180 | // void MfFile::ReadMfRecord(long daddr, MfRecord &m)
|
|---|
| 181 | //
|
|---|
| 182 | // Reads a master file record into the master record object m.
|
|---|
| 183 | // Non blocked version
|
|---|
| 184 | //----------------------------------------------------------------------------------
|
|---|
| 185 | void MfFile::ReadMfRecord(long daddr, MfRecord &m)
|
|---|
| 186 | {
|
|---|
| 187 | m.Clear();
|
|---|
| 188 | ReadLeader(daddr, m); // Read record leader (Leader is added to record)
|
|---|
| 189 | m.ExtractSubLeader();
|
|---|
| 190 |
|
|---|
| 191 | //TRACE("\nReadMfRecord -- mfn=%ld mfrl=%d", m.GetMfn(), m.GetMfrl());
|
|---|
| 192 | //assert(m.CheckIntegrity());
|
|---|
| 193 | int mfrl = m.GetMfrl();
|
|---|
| 194 | if (mfrl < 0) mfrl = -mfrl; // mfrl can be negative!!!!
|
|---|
| 195 | char* p = new char[mfrl];
|
|---|
| 196 | CFileBase::Fetch(p, mfrl, daddr);
|
|---|
| 197 | m.AddToRecord(p+GetLeaderSize(), mfrl-GetLeaderSize());
|
|---|
| 198 | delete[] p;
|
|---|
| 199 | nextaddr_ += mfrl;
|
|---|
| 200 | int mfb = nextaddr_ / MFBLKSIZE + 1;
|
|---|
| 201 | int mfp = nextaddr_ % MFBLKSIZE;
|
|---|
| 202 | if (mfp > MFBLKSIZE - GetMinLeaderSize())
|
|---|
| 203 | {
|
|---|
| 204 | mfb++;
|
|---|
| 205 | mfp = 0;
|
|---|
| 206 | }
|
|---|
| 207 | nextaddr_ = (mfb-1)*MFBLKSIZE + mfp;
|
|---|
| 208 | m.DecomposeRecord();
|
|---|
| 209 | }
|
|---|
| 210 |
|
|---|
| 211 | //---------------------------------------------------------------------------------
|
|---|
| 212 | // void MfFile::WriteMfRecord(long daddr, MfRecord &m)
|
|---|
| 213 | //
|
|---|
| 214 | // Stores Master record object m to disk address daddr
|
|---|
| 215 | // Non blocked version
|
|---|
| 216 | //---------------------------------------------------------------------------------
|
|---|
| 217 | void MfFile::WriteMfRecord(long daddr, MfRecord &m)
|
|---|
| 218 | {
|
|---|
| 219 | }
|
|---|
| 220 | /////////////////////////////////////////////////////////////////////////////////////
|
|---|
| 221 | // Master file locking methods
|
|---|
| 222 |
|
|---|
| 223 |
|
|---|
| 224 |
|
|---|
| 225 | //-----------------------------------------------------------------------------------
|
|---|
| 226 | // void MfFile::InitFileLockHdr(SMfLockHeader &hdr)
|
|---|
| 227 | //
|
|---|
| 228 | // Initialize a the lock header for a newly constructed file lock header.
|
|---|
| 229 | //-----------------------------------------------------------------------------------
|
|---|
| 230 | void MfFile::InitFileLockHdr(SMfLockHeader &hdr)
|
|---|
| 231 | {
|
|---|
| 232 | hdr.lockProtect_ = (uint32_t)0;
|
|---|
| 233 | hdr.readLock_ = (uint32_t)0;
|
|---|
| 234 | hdr.writeLock_ = (uint32_t)0;
|
|---|
| 235 | }
|
|---|
| 236 |
|
|---|
| 237 | //-----------------------------------------------------------------------------------
|
|---|
| 238 | // FileError MfFile::WriteFileLockHdr(const SMfLockHeader &hdr)
|
|---|
| 239 | //
|
|---|
| 240 | // Write the lock header to the file.
|
|---|
| 241 | // Returns a non-zero value to indicate an error condition or zero if successful.
|
|---|
| 242 | //-----------------------------------------------------------------------------------
|
|---|
| 243 | FileError MfFile::WriteFileLockHdr(const SMfLockHeader &hdr)
|
|---|
| 244 | {
|
|---|
| 245 |
|
|---|
| 246 | return CFileBase::Store(&hdr, sizeof(SMfLockHeader), sizeof(SMfHeader));
|
|---|
| 247 | }
|
|---|
| 248 |
|
|---|
| 249 | //-----------------------------------------------------------------------------------
|
|---|
| 250 | // FileError MfFile::ReadFileLockHdr(SMfLockHeader &hdr)
|
|---|
| 251 | //
|
|---|
| 252 | // Read the lock header from the file.
|
|---|
| 253 | // Returns a non-zero value to indicate an error condition or zero if successful.
|
|---|
| 254 | //-----------------------------------------------------------------------------------
|
|---|
| 255 | FileError MfFile::ReadFileLockHdr(SMfLockHeader &hdr)
|
|---|
| 256 | {
|
|---|
| 257 |
|
|---|
| 258 | return CFileBase::Fetch(&hdr, sizeof(SMfLockHeader), sizeof(SMfHeader));
|
|---|
| 259 | }
|
|---|
| 260 |
|
|---|
| 261 | //-----------------------------------------------------------------------------------
|
|---|
| 262 | // int MfFile::LockFile(CFileMgrLockType l_type)
|
|---|
| 263 | //
|
|---|
| 264 | // Lock the file and set the lock access mode to shared or exclusive.
|
|---|
| 265 | // Returns a non-zero value if the file cannot be locked or the lock variable cannot
|
|---|
| 266 | // be changed because it is exclusive or another thread is currently updating it.
|
|---|
| 267 | //-----------------------------------------------------------------------------------
|
|---|
| 268 | int MfFile::LockFile(MfLockType l_type)
|
|---|
| 269 | {
|
|---|
| 270 | // Read the file lock to ensure that this file has a lock header
|
|---|
| 271 | // and to keep the header in sync during multiple file access.
|
|---|
| 272 | SMfLockHeader lock_header;
|
|---|
| 273 | if (ReadFileLockHdr(lock_header) != FILE_NO_ERROR)
|
|---|
| 274 | return fileError_;
|
|---|
| 275 |
|
|---|
| 276 | // Cannot modifiy this lock until the thread holding it releases the
|
|---|
| 277 | // lock header.
|
|---|
| 278 | if (lock_header.lockProtect_ != 0)
|
|---|
| 279 | {
|
|---|
| 280 | fileError_ = ISIS_MFLOCK_ACCESS_ERROR;
|
|---|
| 281 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 282 | throw CFileBaseException(fileError_);
|
|---|
| 283 | #else
|
|---|
| 284 | return fileError_;
|
|---|
| 285 | #endif
|
|---|
| 286 | }
|
|---|
| 287 |
|
|---|
| 288 | switch (l_type)
|
|---|
| 289 | {
|
|---|
| 290 | case MF_WRITE_LOCK :
|
|---|
| 291 | // Cannot obtain an exclusive lock until all the threads in the
|
|---|
| 292 | // read lock queue have finished
|
|---|
| 293 | if ((lock_header.readLock_ != 0) ||
|
|---|
| 294 | (lock_header.writeLock_ != 0))
|
|---|
| 295 | {
|
|---|
| 296 | fileError_ = ISIS_MFLOCK_ERROR;
|
|---|
| 297 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 298 | throw CFileBaseException(fileError_);
|
|---|
| 299 | #else
|
|---|
| 300 | return fileError_;
|
|---|
| 301 | #endif
|
|---|
| 302 | }
|
|---|
| 303 | else
|
|---|
| 304 | {
|
|---|
| 305 | lock_header.writeLock_ = 1;
|
|---|
| 306 | }
|
|---|
| 307 |
|
|---|
| 308 | lock_header.lockProtect_ = 1;
|
|---|
| 309 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 310 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 311 | return fileError_;
|
|---|
| 312 |
|
|---|
| 313 | // Skip over the read lock member
|
|---|
| 314 | SeekTo(sizeof(SMfHeader) + (sizeof(uint32_t) * 2));
|
|---|
| 315 | if (CFileBase::Store(&lock_header.writeLock_, sizeof(uint32_t)) !=
|
|---|
| 316 | FILE_NO_ERROR)
|
|---|
| 317 | return fileError_;
|
|---|
| 318 |
|
|---|
| 319 | lock_header.lockProtect_ = (uint32_t)0;
|
|---|
| 320 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 321 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 322 | return fileError_;
|
|---|
| 323 | break;
|
|---|
| 324 |
|
|---|
| 325 | case MF_READ_LOCK :
|
|---|
| 326 | // This lock is exclusively owned and cannot be read locked
|
|---|
| 327 | // until the thread holding this lock release the exclusive lock.
|
|---|
| 328 | if (lock_header.writeLock_ == 1)
|
|---|
| 329 | {
|
|---|
| 330 | fileError_ = ISIS_MFLOCK_ERROR;
|
|---|
| 331 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 332 | throw CFileBaseException(fileError_);
|
|---|
| 333 | #else
|
|---|
| 334 | return fileError_;
|
|---|
| 335 | #endif
|
|---|
| 336 | }
|
|---|
| 337 |
|
|---|
| 338 | if (lock_header.readLock_ < 0xFFFFFFFF)
|
|---|
| 339 | {
|
|---|
| 340 | lock_header.readLock_++;
|
|---|
| 341 | }
|
|---|
| 342 | else
|
|---|
| 343 | {
|
|---|
| 344 | fileError_ = ISIS_MFLOCK_ERROR;
|
|---|
| 345 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 346 | throw CFileBaseException(fileError_);
|
|---|
| 347 | #else
|
|---|
| 348 | return fileError_;
|
|---|
| 349 | #endif
|
|---|
| 350 | }
|
|---|
| 351 |
|
|---|
| 352 | lock_header.lockProtect_ = 1;
|
|---|
| 353 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 354 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 355 | return fileError_;
|
|---|
| 356 |
|
|---|
| 357 | if (CFileBase::Store(&lock_header.readLock_, sizeof(uint32_t)) !=
|
|---|
| 358 | FILE_NO_ERROR)
|
|---|
| 359 | return fileError_;
|
|---|
| 360 |
|
|---|
| 361 | lock_header.lockProtect_ = (uint32_t)0;
|
|---|
| 362 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 363 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 364 | return fileError_;
|
|---|
| 365 | break;
|
|---|
| 366 |
|
|---|
| 367 | default: // Invalid lock type specified
|
|---|
| 368 | fileError_ = ISIS_INVALID_LOCK_TYPE;
|
|---|
| 369 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 370 | throw CFileBaseException(fileError_);
|
|---|
| 371 | #else
|
|---|
| 372 | return fileError_;
|
|---|
| 373 | #endif
|
|---|
| 374 | }
|
|---|
| 375 |
|
|---|
| 376 | return fileError_ = fileError_ = FILE_NO_ERROR;
|
|---|
| 377 | }
|
|---|
| 378 |
|
|---|
| 379 | //-----------------------------------------------------------------------------------
|
|---|
| 380 | // int MfFile::UnlockFile(CFileMgrLockType l_type)
|
|---|
| 381 | //
|
|---|
| 382 | // Unlock the file. Returns a non-zero value if the file cannot be unlocked or the
|
|---|
| 383 | // lock variable cannot be changed because it is exclusive or another thread is
|
|---|
| 384 | // currently updating it.
|
|---|
| 385 | //-----------------------------------------------------------------------------------
|
|---|
| 386 | int MfFile::UnlockFile(MfLockType l_type)
|
|---|
| 387 | {
|
|---|
| 388 |
|
|---|
| 389 | // Read the file lock to ensure that this file has a lock header
|
|---|
| 390 | // and to keep the header in sync during multiple file access.
|
|---|
| 391 | SMfLockHeader lock_header;
|
|---|
| 392 | if (ReadFileLockHdr(lock_header) != FILE_NO_ERROR)
|
|---|
| 393 | return fileError_;
|
|---|
| 394 |
|
|---|
| 395 | // Cannot modifiy this lock until the thread holding it releases the
|
|---|
| 396 | // lock header.
|
|---|
| 397 | if (lock_header.lockProtect_ != 0)
|
|---|
| 398 | {
|
|---|
| 399 | fileError_ = ISIS_MFLOCK_ACCESS_ERROR;
|
|---|
| 400 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 401 | throw CFileBaseException(fileError_);
|
|---|
| 402 | #else
|
|---|
| 403 | return fileError_;
|
|---|
| 404 | #endif
|
|---|
| 405 | }
|
|---|
| 406 |
|
|---|
| 407 | switch (l_type)
|
|---|
| 408 | {
|
|---|
| 409 | case MF_WRITE_LOCK :
|
|---|
| 410 | if (lock_header.writeLock_ == 0)
|
|---|
| 411 | return FILE_NO_ERROR;
|
|---|
| 412 | else
|
|---|
| 413 | lock_header.writeLock_ = 0;
|
|---|
| 414 |
|
|---|
| 415 | lock_header.lockProtect_ = 1;
|
|---|
| 416 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 417 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 418 | return fileError_;
|
|---|
| 419 |
|
|---|
| 420 | // Skip over the read lock member
|
|---|
| 421 | SeekTo(sizeof(SMfHeader) + (sizeof(uint32_t) * 2));
|
|---|
| 422 | if (CFileBase::Store(&lock_header.writeLock_, sizeof(uint32_t)) !=
|
|---|
| 423 | FILE_NO_ERROR)
|
|---|
| 424 | return fileError_;
|
|---|
| 425 |
|
|---|
| 426 | lock_header.lockProtect_ = (uint32_t)0;
|
|---|
| 427 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 428 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 429 | return fileError_;
|
|---|
| 430 | break;
|
|---|
| 431 |
|
|---|
| 432 | case MF_READ_LOCK :
|
|---|
| 433 | if (lock_header.readLock_ == 0) // This record is not locked
|
|---|
| 434 | return fileError_ = FILE_NO_ERROR;
|
|---|
| 435 | else if (lock_header.readLock_ > 0) // Prevent read lock rollover
|
|---|
| 436 | lock_header.readLock_--;
|
|---|
| 437 | else
|
|---|
| 438 | lock_header.readLock_ = 0;
|
|---|
| 439 |
|
|---|
| 440 | lock_header.lockProtect_ = 1;
|
|---|
| 441 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 442 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 443 | return fileError_;
|
|---|
| 444 |
|
|---|
| 445 | if (CFileBase::Store(&lock_header.readLock_, sizeof(uint32_t)) !=
|
|---|
| 446 | FILE_NO_ERROR)
|
|---|
| 447 | return fileError_;
|
|---|
| 448 |
|
|---|
| 449 | lock_header.lockProtect_ = (uint32_t)0;
|
|---|
| 450 | if (CFileBase::Store(&lock_header.lockProtect_, sizeof(uint32_t),
|
|---|
| 451 | sizeof(SMfHeader)) != FILE_NO_ERROR)
|
|---|
| 452 | return fileError_;
|
|---|
| 453 | break;
|
|---|
| 454 |
|
|---|
| 455 | default: // Invalid lock type specified
|
|---|
| 456 | fileError_ = FMGR_INVALID_LOCK_TYPE;
|
|---|
| 457 | #ifdef __CPP_EXCEPTIONS__
|
|---|
| 458 | throw CFileBaseException(fileError_);
|
|---|
| 459 | #else
|
|---|
| 460 | return fileError_;
|
|---|
| 461 | #endif
|
|---|
| 462 | }
|
|---|
| 463 |
|
|---|
| 464 | return fileError_ = fileError_ = FILE_NO_ERROR;
|
|---|
| 465 | }
|
|---|
| 466 |
|
|---|
| 467 | //-----------------------------------------------------------------------------------
|
|---|
| 468 | // FileError MfFile::ResetFileLock()
|
|---|
| 469 | //
|
|---|
| 470 | // Reset the file's lock header. This function will clear all the file lock fields
|
|---|
| 471 | // without testing the lock or the lock protect. Returns a non-zero value to indicate
|
|---|
| 472 | // an error condition or zero if successful.
|
|---|
| 473 | //-----------------------------------------------------------------------------------
|
|---|
| 474 | FileError MfFile::ResetFileLock()
|
|---|
| 475 | {
|
|---|
| 476 | SMfLockHeader lock_header;
|
|---|
| 477 | InitFileLockHdr(lock_header);
|
|---|
| 478 | return WriteFileLockHdr(lock_header);
|
|---|
| 479 | }
|
|---|
