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 #ifdef __GNUG__
  14 #pragma implementation "cachedb.h"
  15 #endif
  16
  17 #include "cachedb.h"
  18
  19 #include <apti18n.h>
  20 #include <apt-pkg/error.h>
  21 #include <apt-pkg/md5.h>
  22 #include <apt-pkg/sha1.h>
  23 #include <apt-pkg/sha256.h>
  24 #include <apt-pkg/strutl.h>
  25 #include <apt-pkg/configuration.h>
  26
  27 #include <netinet/in.h>       // htonl, etc
  28                                                                         /*}}}*/
  29
  30 // CacheDB::ReadyDB - Ready the DB2                                     /*{{{*/
  31 // ---------------------------------------------------------------------
  32 /* This opens the DB2 file for caching package information */
  33 bool CacheDB::ReadyDB(string DB)
  34 {
  35    int err;
  36
  37    ReadOnly = _config->FindB("APT::FTPArchive::ReadOnlyDB",false);
  38
  39    // Close the old DB
  40    if (Dbp != 0)
  41       Dbp->close(Dbp,0);
  42
  43    /* Check if the DB was disabled while running and deal with a
  44       corrupted DB */
  45    if (DBFailed() == true)
  46    {
  47       _error->Warning(_("DB was corrupted, file renamed to %s.old"),DBFile.c_str());
  48       rename(DBFile.c_str(),(DBFile+".old").c_str());
  49    }
  50
  51    DBLoaded = false;
  52    Dbp = 0;
  53    DBFile = string();
  54
  55    if (DB.empty())
  56       return true;
  57
  58    db_create(&Dbp, NULL, 0);
  59    if ((err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_BTREE,
  60                         (ReadOnly?DB_RDONLY:DB_CREATE),
  61                         0644)) != 0)
  62    {
  63       if (err == DB_OLD_VERSION)
  64       {
  65           _error->Warning(_("DB is old, attempting to upgrade %s"),DBFile.c_str());
  66           err = Dbp->upgrade(Dbp, DB.c_str(), 0);
  67           if (!err)
  68              err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_HASH,
  69                             (ReadOnly?DB_RDONLY:DB_CREATE), 0644);
  70
  71       }
  72       if (err)
  73       {
  74           Dbp = 0;
  75           return _error->Error(_("Unable to open DB file %s: %s"),DB.c_str(), db_strerror(err));
  76       }
  77    }
  78
  79    DBFile = DB;
  80    DBLoaded = true;
  81    return true;
  82 }
  83                                                                         /*}}}*/
  84 // CacheDB::OpenFile - Open the filei                                   /*{{{*/
  85 // ---------------------------------------------------------------------
  86 /* */
  87 bool CacheDB::OpenFile()
  88 {
  89         Fd = new FileFd(FileName,FileFd::ReadOnly);
  90         if (_error->PendingError() == true)
  91         {
  92                 delete Fd;
  93                 Fd = NULL;
  94                 return false;
  95         }
  96         return true;
  97 }
  98                                                                         /*}}}*/
  99 // CacheDB::GetFileStat - Get stats from the file                       /*{{{*/
 100 // ---------------------------------------------------------------------
 101 /* This gets the size from the database if it's there.  If we need
 102  * to look at the file, also get the mtime from the file. */
 103 bool CacheDB::GetFileStat()
 104 {
 105         if ((CurStat.Flags & FlSize) == FlSize)
 106         {
 107                 /* Already worked out the file size */
 108         }
 109         else
 110         {
 111                 /* Get it from the file. */
 112                 if (Fd == NULL && OpenFile() == false)
 113                 {
 114                         return false;
 115                 }
 116                 // Stat the file
 117                 struct stat St;
 118                 if (fstat(Fd->Fd(),&St) != 0)
 119                 {
 120                         return _error->Errno("fstat",
 121                                 _("Failed to stat %s"),FileName.c_str());
 122                 }
 123                 CurStat.FileSize = St.st_size;
 124                 CurStat.mtime = htonl(St.st_mtime);
 125                 CurStat.Flags |= FlSize;
 126         }
 127         return true;
 128 }
 129                                                                         /*}}}*/
 130 // CacheDB::GetCurStat - Set the CurStat variable.                      /*{{{*/
 131 // ---------------------------------------------------------------------
 132 /* Sets the CurStat variable.  Either to 0 if no database is used
 133  * or to the value in the database if one is used */
 134 bool CacheDB::GetCurStat()
 135 {
 136    memset(&CurStat,0,sizeof(CurStat));
 137
 138         if (DBLoaded)
 139         {
 140                 /* First see if thre is anything about it
 141                    in the database */
 142
 143                 /* Get the flags (and mtime) */
 144    InitQuery("st");
 145    // Ensure alignment of the returned structure
 146    Data.data = &CurStat;
 147    Data.ulen = sizeof(CurStat);
 148    Data.flags = DB_DBT_USERMEM;
 149                 if (Get() == false)
 150       {
 151          CurStat.Flags = 0;
 152       }
 153                 CurStat.Flags = ntohl(CurStat.Flags);
 154                 CurStat.FileSize = ntohl(CurStat.FileSize);
 155    }
 156         return true;
 157 }
 158                                                                         /*}}}*/
 159 // CacheDB::GetFileInfo - Get all the info about the file               /*{{{*/
 160 // ---------------------------------------------------------------------
 161 bool CacheDB::GetFileInfo(string FileName, bool DoControl, bool DoContents,
 162                                 bool GenContentsOnly,
 163                                 bool DoMD5, bool DoSHA1, bool DoSHA256)
 164 {
 165         this->FileName = FileName;
 166
 167         if (GetCurStat() == false)
 168    {
 169                 return false;
 170    }
 171    OldStat = CurStat;
 172
 173         if (GetFileStat() == false)
 174         {
 175                 delete Fd;
 176                 Fd = NULL;
 177                 return false;
 178         }
 179
 180         Stats.Bytes += CurStat.FileSize;
 181         Stats.Packages++;
 182
 183         if (DoControl && LoadControl() == false
 184                 || DoContents && LoadContents(GenContentsOnly) == false
 185                 || DoMD5 && GetMD5(false) == false
 186                 || DoSHA1 && GetSHA1(false) == false
 187                 || DoSHA256 && GetSHA256(false) == false)
 188         {
 189                 delete Fd;
 190                 Fd = NULL;
 191                 delete DebFile;
 192                 DebFile = NULL;
 193                 return false;
 194         }
 195
 196         delete Fd;
 197         Fd = NULL;
 198         delete DebFile;
 199         DebFile = NULL;
 200
 201    return true;
 202 }
 203                                                                         /*}}}*/
 204 // CacheDB::LoadControl - Load Control information                      /*{{{*/
 205 // ---------------------------------------------------------------------
 206 /* */
 207 bool CacheDB::LoadControl()
 208 {
 209    // Try to read the control information out of the DB.
 210    if ((CurStat.Flags & FlControl) == FlControl)
 211    {
 212       // Lookup the control information
 213       InitQuery("cl");
 214       if (Get() == true && Control.TakeControl(Data.data,Data.size) == true)
 215             return true;
 216       CurStat.Flags &= ~FlControl;
 217    }
 218
 219    if (Fd == NULL && OpenFile() == false)
 220    {
 221       return false;
 222    }
 223    // Create a deb instance to read the archive
 224    if (DebFile == 0)
 225    {
 226       DebFile = new debDebFile(*Fd);
 227       if (_error->PendingError() == true)
 228          return false;
 229    }
 230
 231    Stats.Misses++;
 232    if (Control.Read(*DebFile) == false)
 233       return false;
 234
 235    if (Control.Control == 0)
 236       return _error->Error(_("Archive has no control record"));
 237
 238    // Write back the control information
 239    InitQuery("cl");
 240    if (Put(Control.Control,Control.Length) == true)
 241       CurStat.Flags |= FlControl;
 242    return true;
 243 }
 244                                                                         /*}}}*/
 245 // CacheDB::LoadContents - Load the File Listing                        /*{{{*/
 246 // ---------------------------------------------------------------------
 247 /* */
 248 bool CacheDB::LoadContents(bool GenOnly)
 249 {
 250    // Try to read the control information out of the DB.
 251    if ((CurStat.Flags & FlContents) == FlContents)
 252    {
 253       if (GenOnly == true)
 254          return true;
 255
 256       // Lookup the contents information
 257       InitQuery("cn");
 258       if (Get() == true)
 259       {
 260          if (Contents.TakeContents(Data.data,Data.size) == true)
 261             return true;
 262       }
 263
 264       CurStat.Flags &= ~FlContents;
 265    }
 266
 267    if (Fd == NULL && OpenFile() == false)
 268    {
 269       return false;
 270    }
 271    // Create a deb instance to read the archive
 272    if (DebFile == 0)
 273    {
 274       DebFile = new debDebFile(*Fd);
 275       if (_error->PendingError() == true)
 276          return false;
 277    }
 278
 279    if (Contents.Read(*DebFile) == false)
 280       return false;
 281
 282    // Write back the control information
 283    InitQuery("cn");
 284    if (Put(Contents.Data,Contents.CurSize) == true)
 285       CurStat.Flags |= FlContents;
 286    return true;
 287 }
 288                                                                         /*}}}*/
 289
 290 static string bytes2hex(uint8_t *bytes, size_t length) {
 291    char space[65];
 292    if (length * 2 > sizeof(space) - 1) length = (sizeof(space) - 1) / 2;
 293    for (size_t i = 0; i < length; i++)
 294       snprintf(&space[i*2], 3, "%02x", bytes[i]);
 295    return string(space);
 296 }
 297
 298 static inline unsigned char xdig2num(char dig) {
 299    if (isdigit(dig)) return dig - '0';
 300    if ('a' <= dig && dig <= 'f') return dig - 'a' + 10;
 301    if ('A' <= dig && dig <= 'F') return dig - 'A' + 10;
 302    return 0;
 303 }
 304
 305 static void hex2bytes(uint8_t *bytes, const char *hex, int length) {
 306    while (length-- > 0) {
 307       *bytes = 0;
 308       if (isxdigit(hex[0]) && isxdigit(hex[1])) {
 309           *bytes = xdig2num(hex[0]) * 16 + xdig2num(hex[1]);
 310           hex += 2;
 311       }
 312       bytes++;
 313    }
 314 }
 315
 316 // CacheDB::GetMD5 - Get the MD5 hash                                   /*{{{*/
 317 // ---------------------------------------------------------------------
 318 /* */
 319 bool CacheDB::GetMD5(bool GenOnly)
 320 {
 321    // Try to read the control information out of the DB.
 322    if ((CurStat.Flags & FlMD5) == FlMD5)
 323    {
 324       if (GenOnly == true)
 325          return true;
 326
 327       MD5Res = bytes2hex(CurStat.MD5, sizeof(CurStat.MD5));
 328          return true;
 329       }
 330
 331    Stats.MD5Bytes += CurStat.FileSize;
 332
 333    if (Fd == NULL && OpenFile() == false)
 334    {
 335       return false;
 336    }
 337    MD5Summation MD5;
 338    if (Fd->Seek(0) == false || MD5.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 339       return false;
 340
 341    MD5Res = MD5.Result();
 342    hex2bytes(CurStat.MD5, MD5Res.data(), sizeof(CurStat.MD5));
 343       CurStat.Flags |= FlMD5;
 344    return true;
 345 }
 346                                                                         /*}}}*/
 347 // CacheDB::GetSHA1 - Get the SHA1 hash                                 /*{{{*/
 348 // ---------------------------------------------------------------------
 349 /* */
 350 bool CacheDB::GetSHA1(bool GenOnly)
 351 {
 352    // Try to read the control information out of the DB.
 353    if ((CurStat.Flags & FlSHA1) == FlSHA1)
 354    {
 355       if (GenOnly == true)
 356          return true;
 357
 358       SHA1Res = bytes2hex(CurStat.SHA1, sizeof(CurStat.SHA1));
 359       return true;
 360    }
 361
 362    Stats.SHA1Bytes += CurStat.FileSize;
 363
 364    if (Fd == NULL && OpenFile() == false)
 365    {
 366       return false;
 367    }
 368    SHA1Summation SHA1;
 369    if (Fd->Seek(0) == false || SHA1.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 370       return false;
 371
 372    SHA1Res = SHA1.Result();
 373    hex2bytes(CurStat.SHA1, SHA1Res.data(), sizeof(CurStat.SHA1));
 374    CurStat.Flags |= FlSHA1;
 375    return true;
 376 }
 377                                                                         /*}}}*/
 378 // CacheDB::GetSHA256 - Get the SHA256 hash                             /*{{{*/
 379 // ---------------------------------------------------------------------
 380 /* */
 381 bool CacheDB::GetSHA256(bool GenOnly)
 382 {
 383    // Try to read the control information out of the DB.
 384    if ((CurStat.Flags & FlSHA256) == FlSHA256)
 385    {
 386       if (GenOnly == true)
 387          return true;
 388
 389       SHA256Res = bytes2hex(CurStat.SHA256, sizeof(CurStat.SHA256));
 390       return true;
 391    }
 392
 393    Stats.SHA256Bytes += CurStat.FileSize;
 394
 395    if (Fd == NULL && OpenFile() == false)
 396    {
 397       return false;
 398    }
 399    SHA256Summation SHA256;
 400    if (Fd->Seek(0) == false || SHA256.AddFD(Fd->Fd(),CurStat.FileSize) == false)
 401       return false;
 402
 403    SHA256Res = SHA256.Result();
 404    hex2bytes(CurStat.SHA256, SHA256Res.data(), sizeof(CurStat.SHA256));
 405    CurStat.Flags |= FlSHA256;
 406    return true;
 407 }
 408                                                                         /*}}}*/
 409 // CacheDB::Finish - Write back the cache structure                     /*{{{*/
 410 // ---------------------------------------------------------------------
 411 /* */
 412 bool CacheDB::Finish()
 413 {
 414    // Optimize away some writes.
 415    if (CurStat.Flags == OldStat.Flags &&
 416        CurStat.mtime == OldStat.mtime)
 417       return true;
 418
 419    // Write the stat information
 420    CurStat.Flags = htonl(CurStat.Flags);
 421    CurStat.FileSize = htonl(CurStat.FileSize);
 422    InitQuery("st");
 423    Put(&CurStat,sizeof(CurStat));
 424    CurStat.Flags = ntohl(CurStat.Flags);
 425    CurStat.FileSize = ntohl(CurStat.FileSize);
 426
 427    return true;
 428 }
 429                                                                         /*}}}*/
 430 // CacheDB::Clean - Clean the Database                                  /*{{{*/
 431 // ---------------------------------------------------------------------
 432 /* Tidy the database by removing files that no longer exist at all. */
 433 bool CacheDB::Clean()
 434 {
 435    if (DBLoaded == false)
 436       return true;
 437
 438    /* I'm not sure what VERSION_MINOR should be here.. 2.4.14 certainly
 439       needs the lower one and 2.7.7 needs the upper.. */
 440    DBC *Cursor;
 441    if ((errno = Dbp->cursor(Dbp, NULL, &Cursor, 0)) != 0)
 442       return _error->Error(_("Unable to get a cursor"));
 443
 444    DBT Key;
 445    DBT Data;
 446    memset(&Key,0,sizeof(Key));
 447    memset(&Data,0,sizeof(Data));
 448    while ((errno = Cursor->c_get(Cursor,&Key,&Data,DB_NEXT)) == 0)
 449    {
 450       const char *Colon = (char *)Key.data;
 451       for (; Colon != (char *)Key.data+Key.size && *Colon != ':'; Colon++);
 452       if ((char *)Key.data+Key.size - Colon > 2)
 453       {
 454          if (stringcmp((char *)Key.data,Colon,"st") == 0 ||
 455              stringcmp((char *)Key.data,Colon,"cn") == 0 ||
 456              stringcmp((char *)Key.data,Colon,"cl") == 0)
 457          {
 458             if (FileExists(string(Colon+1,(const char *)Key.data+Key.size)) == true)
 459                 continue;
 460          }
 461       }
 462
 463       Cursor->c_del(Cursor,0);
 464    }
 465
 466    return true;
 467 }
 468                                                                         /*}}}*/