ftparchive/cachedb.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: cachedb.cc,v 1.7 2004/05/08 19:41:01 mdz Exp $
   4 /* ######################################################################
   5
   6    CacheDB
   7
   8    Simple uniform interface to a cache database.
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #include "cachedb.h"
  14
  15 #include <apti18n.h>
  16 #include <apt-pkg/error.h>
  17 #include <apt-pkg/md5.h>
  18 #include <apt-pkg/sha1.h>
  19 #include <apt-pkg/sha2.h>
  20 #include <apt-pkg/strutl.h>
  21 #include <apt-pkg/configuration.h>
  22
  23 #include <netinet/in.h>       // htonl, etc
  24                                                                         /*}}}*/
  25
  26 // CacheDB::ReadyDB - Ready the DB2                                     /*{{{*/
  27 // ---------------------------------------------------------------------
  28 /* This opens the DB2 file for caching package information */
  29 bool CacheDB::ReadyDB(string const &DB)
  30 {
  31    int err;
  32
  33    ReadOnly = _config->FindB("APT::FTPArchive::ReadOnlyDB",false);
  34
  35    // Close the old DB
  36    if (Dbp != 0)
  37       Dbp->close(Dbp,0);
  38
  39    /* Check if the DB was disabled while running and deal with a
  40       corrupted DB */
  41    if (DBFailed() == true)
  42    {
  43       _error->Warning(_("DB was corrupted, file renamed to %s.old"),DBFile.c_str());
  44       rename(DBFile.c_str(),(DBFile+".old").c_str());
  45    }
  46
  47    DBLoaded = false;
  48    Dbp = 0;
  49    DBFile = string();
  50
  51    if (DB.empty())
  52       return true;
  53
  54    db_create(&Dbp, NULL, 0);
  55    if ((err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_BTREE,
  56                         (ReadOnly?DB_RDONLY:DB_CREATE),
  57                         0644)) != 0)
  58    {
  59       if (err == DB_OLD_VERSION)
  60       {
  61           _error->Warning(_("DB is old, attempting to upgrade %s"),DBFile.c_str());
  62           err = Dbp->upgrade(Dbp, DB.c_str(), 0);
  63           if (!err)
  64              err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_HASH,
  65                             (ReadOnly?DB_RDONLY:DB_CREATE), 0644);
  66
  67       }
  68       // the database format has changed from DB_HASH to DB_BTREE in
  69       // apt 0.6.44
  70       if (err == EINVAL)
  71       {
  72          _error->Error(_("DB format is invalid. If you upgraded from an older version of apt, please remove and re-create the database."));
  73       }
  74       if (err)
  75       {
  76           Dbp = 0;
  77           return _error->Error(_("Unable to open DB file %s: %s"),DB.c_str(), db_strerror(err));
  78       }
  79    }
  80
  81    DBFile = DB;
  82    DBLoaded = true;
  83    return true;
  84 }
  85                                                                         /*}}}*/
  86 // CacheDB::OpenFile - Open the file                                    /*{{{*/
  87 // ---------------------------------------------------------------------
  88 /* */
  89 bool CacheDB::OpenFile()
  90 {
  91         Fd = new FileFd(FileName,FileFd::ReadOnly);
  92         if (_error->PendingError() == true)
  93         {
  94                 delete Fd;
  95                 Fd = NULL;
  96                 return false;
  97         }
  98         return true;
  99 }
 100                                                                         /*}}}*/
 101 // CacheDB::GetFileStat - Get stats from the file                       /*{{{*/
 102 // ---------------------------------------------------------------------
 103 /* This gets the size from the database if it's there.  If we need
 104  * to look at the file, also get the mtime from the file. */
 105 bool CacheDB::GetFileStat(bool const &doStat)
 106 {
 107         if ((CurStat.Flags & FlSize) == FlSize && doStat == false)
 108         {
 109                 /* Already worked out the file size */
 110         }
 111         else
 112         {
 113                 /* Get it from the file. */
 114                 if (Fd == NULL && OpenFile() == false)
 115                 {
 116                         return false;
 117                 }
 118                 // Stat the file
 119                 struct stat St;
 120                 if (fstat(Fd->Fd(),&St) != 0)
 121                 {
 122                         return _error->Errno("fstat",
 123                                 _("Failed to stat %s"),FileName.c_str());
 124                 }
 125                 CurStat.FileSize = St.st_size;
 126                 CurStat.mtime = htonl(St.st_mtime);
 127                 CurStat.Flags |= FlSize;
 128         }
 129         return true;
 130 }
 131                                                                         /*}}}*/
 132 // CacheDB::GetCurStat - Set the CurStat variable.                      /*{{{*/
 133 // ---------------------------------------------------------------------
 134 /* Sets the CurStat variable.  Either to 0 if no database is used
 135  * or to the value in the database if one is used */
 136 bool CacheDB::GetCurStat()
 137 {
 138    memset(&CurStat,0,sizeof(CurStat));
 139
 140         if (DBLoaded)
 141         {
 142                 /* First see if there is anything about it
 143                    in the database */
 144
 145                 /* Get the flags (and mtime) */
 146    InitQuery("st");
 147    // Ensure alignment of the returned structure
 148    Data.data = &CurStat;
 149    Data.ulen = sizeof(CurStat);
 150    Data.flags = DB_DBT_USERMEM;
 151                 if (Get() == false)
 152       {
 153          CurStat.Flags = 0;
 154       }
 155                 CurStat.Flags = ntohl(CurStat.Flags);
 156                 CurStat.FileSize = ntohl(CurStat.FileSize);
 157    }
 158         return true;
 159 }
 160                                                                         /*}}}*/
 161 // CacheDB::GetFileInfo - Get all the info about the file               /*{{{*/
 162 // ---------------------------------------------------------------------
 163 bool CacheDB::GetFileInfo(string const &FileName, bool const &DoControl, bool const &DoContents,
 164                                 bool const &GenContentsOnly, bool const &DoMD5, bool const &DoSHA1,
 165                                 bool const &DoSHA256,   bool const &DoSHA512,
 166                           bool const &checkMtime)
 167 {
 168         this->FileName = FileName;
 169
 170         if (GetCurStat() == false)
 171    {
 172                 return false;
 173    }
 174    OldStat = CurStat;
 175
 176         if (GetFileStat(checkMtime) == false)
 177         {
 178                 delete Fd;
 179                 Fd = NULL;
 180                 return false;
 181         }
 182
 183     /* if mtime changed, update CurStat from disk */
 184     if (checkMtime == true && OldStat.mtime != CurStat.mtime)
 185         CurStat.Flags = FlSize;
 186
 187         Stats.Bytes += CurStat.FileSize;
 188         Stats.Packages++;
 189
 190         if ((DoControl && LoadControl() == false)
 191                 || (DoContents && LoadContents(GenContentsOnly) == false)
 192                 || (DoMD5 && GetMD5(false) == false)
 193                 || (DoSHA1 && GetSHA1(false) == false)
 194                 || (DoSHA256 && GetSHA256(false) == false)
 195                 || (DoSHA512 && GetSHA512(false) == false)
 196            )
 197         {
 198                 delete Fd;
 199                 Fd = NULL;
 200                 delete DebFile;
 201                 DebFile = NULL;
 202                 return false;
 203         }
 204
 205         delete Fd;
 206         Fd = NULL;
 207         delete DebFile;
 208         DebFile = NULL;
 209
 210    return true;
 211 }
 212                                                                         /*}}}*/
 213 // CacheDB::LoadControl - Load Control information                      /*{{{*/
 214 // ---------------------------------------------------------------------
 215 /* */
 216 bool CacheDB::LoadControl()
 217 {
 218    // Try to read the control information out of the DB.
 219    if ((CurStat.Flags & FlControl) == FlControl)
 220    {
 221       // Lookup the control information
 222       InitQuery("cl");
 223       if (Get() == true && Control.TakeControl(Data.data,Data.size) == true)
 224             return true;
 225       CurStat.Flags &= ~FlControl;
 226    }
 227
 228    if (Fd == NULL && OpenFile() == false)
 229    {
 230       return false;
 231    }
 232    // Create a deb instance to read the archive
 233    if (DebFile == 0)
 234    {
 235       DebFile = new debDebFile(*Fd);
 236       if (_error->PendingError() == true)
 237          return false;
 238    }
 239
 240    Stats.Misses++;
 241    if (Control.Read(*DebFile) == false)
 242       return false;
 243
 244    if (Control.Control == 0)
 245       return _error->Error(_("Archive has no control record"));
 246
 247    // Write back the control information
 248    InitQuery("cl");
 249    if (Put(Control.Control,Control.Length) == true)
 250       CurStat.Flags |= FlControl;
 251    return true;
 252 }
 253                                                                         /*}}}*/
 254 // CacheDB::LoadContents - Load the File Listing                        /*{{{*/
 255 // ---------------------------------------------------------------------
 256 /* */
 257 bool CacheDB::LoadContents(bool const &GenOnly)
 258 {
 259    // Try to read the control information out of the DB.
 260    if ((CurStat.Flags & FlContents) == FlContents)
 261    {
 262       if (GenOnly == true)
 263          return true;
 264
 265       // Lookup the contents information
 266       InitQuery("cn");
 267       if (Get() == true)
 268       {
 269          if (Contents.TakeContents(Data.data,Data.size) == true)
 270             return true;
 271       }
 272
 273       CurStat.Flags &= ~FlContents;
 274    }
 275
 276    if (Fd == NULL && OpenFile() == false)
 277    {
 278       return false;
 279    }
 280    // Create a deb instance to read the archive
 281    if (DebFile == 0)
 282    {
 283       DebFile = new debDebFile(*Fd);
 284       if (_error->PendingError() == true)
 285          return false;
 286    }
 287
 288    if (Contents.Read(*DebFile) == false)
 289       return false;
 290
 291    // Write back the control information
 292    InitQuery("cn");
 293    if (Put(Contents.Data,Contents.CurSize) == true)
 294       CurStat.Flags |= FlContents;
 295    return true;
 296 }
 297                                                                         /*}}}*/
 298
 299 static string bytes2hex(uint8_t *bytes, size_t length) {
 300    char space[65];
 301    if (length * 2 > sizeof(space) - 1) length = (sizeof(space) - 1) / 2;
 302    for (size_t i = 0; i < length; i++)
 303       snprintf(&space[i*2], 3, "%02x", bytes[i]);
 304    return string(space);
 305 }
 306
 307 static inline unsigned char xdig2num(char const &dig) {
 308    if (isdigit(dig)) return dig - '0';
 309    if ('a' <= dig && dig <= 'f') return dig - 'a' + 10;
 310    if ('A' <= dig && dig <= 'F') return dig - 'A' + 10;
 311    return 0;
 312 }
 313
 314 static void hex2bytes(uint8_t *bytes, const char *hex, int length) {
 315    while (length-- > 0) {
 316       *bytes = 0;
 317       if (isxdigit(hex[0]) && isxdigit(hex[1])) {
 318           *bytes = xdig2num(hex[0]) * 16 + xdig2num(hex[1]);
 319           hex += 2;
 320       }
 321       bytes++;
 322    }
 323 }
 324
 325 // CacheDB::GetMD5 - Get the MD5 hash                                   /*{{{*/
 326 // ---------------------------------------------------------------------
 327 /* */
 328 bool CacheDB::GetMD5(bool const &GenOnly)
 329 {
 330    // Try to read the control information out of the DB.
 331    if ((CurStat.Flags & FlMD5) == FlMD5)
 332    {
 333       if (GenOnly == true)
 334          return true;
 335
 336       MD5Res = bytes2hex(CurStat.MD5, sizeof(CurStat.MD5));
 337          return true;
 338       }
 339
 340    Stats.MD5Bytes += CurStat.FileSize;
 341
 342    if (Fd == NULL && OpenFile() == false)
 343    {
 344       return false;
 345    }
 346    MD5Summation MD5;
 347    if (Fd->Seek(0) == false || MD5.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 348       return false;
 349
 350    MD5Res = MD5.Result();
 351    hex2bytes(CurStat.MD5, MD5Res.data(), sizeof(CurStat.MD5));
 352       CurStat.Flags |= FlMD5;
 353    return true;
 354 }
 355                                                                         /*}}}*/
 356 // CacheDB::GetSHA1 - Get the SHA1 hash                                 /*{{{*/
 357 // ---------------------------------------------------------------------
 358 /* */
 359 bool CacheDB::GetSHA1(bool const &GenOnly)
 360 {
 361    // Try to read the control information out of the DB.
 362    if ((CurStat.Flags & FlSHA1) == FlSHA1)
 363    {
 364       if (GenOnly == true)
 365          return true;
 366
 367       SHA1Res = bytes2hex(CurStat.SHA1, sizeof(CurStat.SHA1));
 368       return true;
 369    }
 370
 371    Stats.SHA1Bytes += CurStat.FileSize;
 372
 373    if (Fd == NULL && OpenFile() == false)
 374    {
 375       return false;
 376    }
 377    SHA1Summation SHA1;
 378    if (Fd->Seek(0) == false || SHA1.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 379       return false;
 380
 381    SHA1Res = SHA1.Result();
 382    hex2bytes(CurStat.SHA1, SHA1Res.data(), sizeof(CurStat.SHA1));
 383    CurStat.Flags |= FlSHA1;
 384    return true;
 385 }
 386                                                                         /*}}}*/
 387 // CacheDB::GetSHA256 - Get the SHA256 hash                             /*{{{*/
 388 // ---------------------------------------------------------------------
 389 /* */
 390 bool CacheDB::GetSHA256(bool const &GenOnly)
 391 {
 392    // Try to read the control information out of the DB.
 393    if ((CurStat.Flags & FlSHA256) == FlSHA256)
 394    {
 395       if (GenOnly == true)
 396          return true;
 397
 398       SHA256Res = bytes2hex(CurStat.SHA256, sizeof(CurStat.SHA256));
 399       return true;
 400    }
 401
 402    Stats.SHA256Bytes += CurStat.FileSize;
 403
 404    if (Fd == NULL && OpenFile() == false)
 405    {
 406       return false;
 407    }
 408    SHA256Summation SHA256;
 409    if (Fd->Seek(0) == false || SHA256.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 410       return false;
 411
 412    SHA256Res = SHA256.Result();
 413    hex2bytes(CurStat.SHA256, SHA256Res.data(), sizeof(CurStat.SHA256));
 414    CurStat.Flags |= FlSHA256;
 415    return true;
 416 }
 417                                                                         /*}}}*/
 418 // CacheDB::GetSHA256 - Get the SHA256 hash                             /*{{{*/
 419 // ---------------------------------------------------------------------
 420 /* */
 421 bool CacheDB::GetSHA512(bool const &GenOnly)
 422 {
 423    // Try to read the control information out of the DB.
 424    if ((CurStat.Flags & FlSHA512) == FlSHA512)
 425    {
 426       if (GenOnly == true)
 427          return true;
 428
 429       SHA512Res = bytes2hex(CurStat.SHA512, sizeof(CurStat.SHA512));
 430       return true;
 431    }
 432
 433    Stats.SHA512Bytes += CurStat.FileSize;
 434
 435    if (Fd == NULL && OpenFile() == false)
 436    {
 437       return false;
 438    }
 439    SHA512Summation SHA512;
 440    if (Fd->Seek(0) == false || SHA512.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 441       return false;
 442
 443    SHA512Res = SHA512.Result();
 444    hex2bytes(CurStat.SHA512, SHA512Res.data(), sizeof(CurStat.SHA512));
 445    CurStat.Flags |= FlSHA512;
 446    return true;
 447 }
 448                                                                         /*}}}*/
 449 // CacheDB::Finish - Write back the cache structure                     /*{{{*/
 450 // ---------------------------------------------------------------------
 451 /* */
 452 bool CacheDB::Finish()
 453 {
 454    // Optimize away some writes.
 455    if (CurStat.Flags == OldStat.Flags &&
 456        CurStat.mtime == OldStat.mtime)
 457       return true;
 458
 459    // Write the stat information
 460    CurStat.Flags = htonl(CurStat.Flags);
 461    CurStat.FileSize = htonl(CurStat.FileSize);
 462    InitQuery("st");
 463    Put(&CurStat,sizeof(CurStat));
 464    CurStat.Flags = ntohl(CurStat.Flags);
 465    CurStat.FileSize = ntohl(CurStat.FileSize);
 466
 467    return true;
 468 }
 469                                                                         /*}}}*/
 470 // CacheDB::Clean - Clean the Database                                  /*{{{*/
 471 // ---------------------------------------------------------------------
 472 /* Tidy the database by removing files that no longer exist at all. */
 473 bool CacheDB::Clean()
 474 {
 475    if (DBLoaded == false)
 476       return true;
 477
 478    /* I'm not sure what VERSION_MINOR should be here.. 2.4.14 certainly
 479       needs the lower one and 2.7.7 needs the upper.. */
 480    DBC *Cursor;
 481    if ((errno = Dbp->cursor(Dbp, NULL, &Cursor, 0)) != 0)
 482       return _error->Error(_("Unable to get a cursor"));
 483
 484    DBT Key;
 485    DBT Data;
 486    memset(&Key,0,sizeof(Key));
 487    memset(&Data,0,sizeof(Data));
 488    while ((errno = Cursor->c_get(Cursor,&Key,&Data,DB_NEXT)) == 0)
 489    {
 490       const char *Colon = (char*)memrchr(Key.data, ':', Key.size);
 491       if (Colon)
 492       {
 493          if (stringcmp(Colon + 1, (char *)Key.data+Key.size,"st") == 0 ||
 494              stringcmp(Colon + 1, (char *)Key.data+Key.size,"cl") == 0 ||
 495              stringcmp(Colon + 1, (char *)Key.data+Key.size,"cn") == 0)
 496          {
 497             if (FileExists(string((const char *)Key.data,Colon)) == true)
 498                 continue;
 499          }
 500       }
 501
 502       Cursor->c_del(Cursor,0);
 503    }
 504    Dbp->compact(Dbp, NULL, NULL, NULL, NULL, DB_FREE_SPACE, NULL);
 505
 506    return true;
 507 }
 508                                                                         /*}}}*/