ftparchive/cachedb.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: cachedb.h,v 1.4 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 #ifndef CACHEDB_H
  13 #define CACHEDB_H
  14
  15 #include <apt-pkg/hashes.h>
  16 #include <apt-pkg/debfile.h>
  17
  18 #include <db.h>
  19 #include <errno.h>
  20 #include <string>
  21 #include <string.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24
  25 #include "contents.h"
  26 #include "sources.h"
  27
  28 class FileFd;
  29
  30
  31 class CacheDB
  32 {
  33    protected:
  34
  35    // Database state/access
  36    DBT Key;
  37    DBT Data;
  38    char TmpKey[600];
  39    DB *Dbp;
  40    bool DBLoaded;
  41    bool ReadOnly;
  42    std::string DBFile;
  43
  44    // Generate a key for the DB of a given type
  45    void _InitQuery(const char *Type)
  46    {
  47       memset(&Key,0,sizeof(Key));
  48       memset(&Data,0,sizeof(Data));
  49       Key.data = TmpKey;
  50       Key.size = snprintf(TmpKey,sizeof(TmpKey),"%s:%s",FileName.c_str(), Type);
  51    }
  52
  53    void InitQueryStats() {
  54       _InitQuery("st");
  55    }
  56    void InitQuerySource() {
  57       _InitQuery("cs");
  58    }
  59    void InitQueryControl() {
  60       _InitQuery("cl");
  61    }
  62    void InitQueryContent() {
  63       _InitQuery("cn");
  64    }
  65
  66    inline bool Get()
  67    {
  68       return Dbp->get(Dbp,0,&Key,&Data,0) == 0;
  69    };
  70    inline bool Put(const void *In,unsigned long const &Length)
  71    {
  72       if (ReadOnly == true)
  73          return true;
  74       Data.size = Length;
  75       Data.data = (void *)In;
  76       if (DBLoaded == true && (errno = Dbp->put(Dbp,0,&Key,&Data,0)) != 0)
  77       {
  78          DBLoaded = false;
  79          return false;
  80       }
  81       return true;
  82    }
  83    bool OpenFile();
  84    void CloseFile();
  85
  86    bool OpenDebFile();
  87    void CloseDebFile();
  88
  89    // GetCurStat needs some compat code, see lp #1274466)
  90    bool GetCurStatCompatOldFormat();
  91    bool GetCurStatCompatNewFormat();
  92    bool GetCurStat();
  93
  94    bool GetFileStat(bool const &doStat = false);
  95    bool LoadControl();
  96    bool LoadContents(bool const &GenOnly);
  97    bool LoadSource();
  98    bool GetHashes(bool const GenOnly, unsigned int const DoHashes);
  99
 100    // Stat info stored in the DB, Fixed types since it is written to disk.
 101    enum FlagList {FlControl = (1<<0),FlMD5=(1<<1),FlContents=(1<<2),
 102                   FlSize=(1<<3), FlSHA1=(1<<4), FlSHA256=(1<<5),
 103                   FlSHA512=(1<<6), FlSource=(1<<7)
 104    };
 105
 106    // the on-disk format changed (FileSize increased to 64bit) in
 107    // commit 650faab0 which will lead to corruption with old caches
 108    struct StatStoreOldFormat
 109    {
 110       uint32_t Flags;
 111       uint32_t mtime;
 112       uint32_t FileSize;
 113       uint8_t  MD5[16];
 114       uint8_t  SHA1[20];
 115       uint8_t  SHA256[32];
 116    } CurStatOldFormat;
 117
 118    // WARNING: this struct is read/written to the DB so do not change the
 119    //          layout of the fields (see lp #1274466), only append to it
 120    struct StatStore
 121    {
 122       uint32_t Flags;
 123       uint32_t mtime;
 124       uint64_t FileSize;
 125       uint8_t  MD5[16];
 126       uint8_t  SHA1[20];
 127       uint8_t  SHA256[32];
 128       uint8_t  SHA512[64];
 129    } CurStat;
 130    struct StatStore OldStat;
 131
 132    // 'set' state
 133    std::string FileName;
 134    FileFd *Fd;
 135    debDebFile *DebFile;
 136
 137    public:
 138
 139    // Data collection helpers
 140    debDebFile::MemControlExtract Control;
 141    ContentsExtract Contents;
 142    DscExtract Dsc;
 143    HashStringList HashesList;
 144
 145    // Runtime statistics
 146    struct Stats
 147    {
 148       double Bytes;
 149       double MD5Bytes;
 150       double SHA1Bytes;
 151       double SHA256Bytes;
 152       double SHA512Bytes;
 153       unsigned long Packages;
 154       unsigned long Misses;
 155       unsigned long long DeLinkBytes;
 156
 157       inline void Add(const Stats &S) {
 158          Bytes += S.Bytes;
 159          MD5Bytes += S.MD5Bytes;
 160          SHA1Bytes += S.SHA1Bytes;
 161          SHA256Bytes += S.SHA256Bytes;
 162          SHA512Bytes += S.SHA512Bytes;
 163          Packages += S.Packages;
 164          Misses += S.Misses;
 165          DeLinkBytes += S.DeLinkBytes;
 166       };
 167       Stats() : Bytes(0), MD5Bytes(0), SHA1Bytes(0), SHA256Bytes(0),
 168                 SHA512Bytes(0),Packages(0), Misses(0), DeLinkBytes(0) {};
 169    } Stats;
 170
 171    bool ReadyDB(std::string const &DB = "");
 172    inline bool DBFailed() {return Dbp != 0 && DBLoaded == false;};
 173    inline bool Loaded() {return DBLoaded == true;};
 174
 175    inline unsigned long long GetFileSize(void) {return CurStat.FileSize;}
 176
 177    bool SetFile(std::string const &FileName,struct stat St,FileFd *Fd);
 178
 179    // terrible old overloaded interface
 180    bool GetFileInfo(std::string const &FileName,
 181          bool const &DoControl,
 182          bool const &DoContents,
 183          bool const &GenContentsOnly,
 184          bool const DoSource,
 185          unsigned int const DoHashes,
 186          bool const &checkMtime = false);
 187
 188    bool Finish();
 189
 190    bool Clean();
 191
 192    explicit CacheDB(std::string const &DB);
 193    ~CacheDB();
 194 };
 195
 196 #endif