From: Ketmar Dark Date: Sat, 12 Oct 2019 21:52:02 +0000 (+0300) Subject: game: added simple database for storing md5 file hashes X-Git-Url: http://deadsoftware.ru/gitweb?p=d2df-sdl.git;a=commitdiff_plain;h=331b05efe2f6761ea29488bc598661f96270909d game: added simple database for storing md5 file hashes --- diff --git a/src/game/Doom2DF.lpr b/src/game/Doom2DF.lpr index 88b0503..875879f 100644 --- a/src/game/Doom2DF.lpr +++ b/src/game/Doom2DF.lpr @@ -141,6 +141,7 @@ uses xprofiler in '../shared/xprofiler.pas', binheap in '../shared/binheap.pas', hashtable in '../shared/hashtable.pas', + fhashdb in '../shared/fhashdb.pas', idpool in '../shared/idpool.pas', xparser in '../shared/xparser.pas', xdynrec in '../shared/xdynrec.pas', diff --git a/src/shared/fhashdb.pas b/src/shared/fhashdb.pas new file mode 100644 index 0000000..7e45c10 --- /dev/null +++ b/src/shared/fhashdb.pas @@ -0,0 +1,476 @@ +(* Copyright (C) Doom 2D: Forever Developers + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, version 3 of the License ONLY. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + *) +{$INCLUDE ../shared/a_modes.inc} +// database of file hashes (md5) +unit fhashdb; + +interface + +uses + SysUtils, Classes, + md5, hashtable, utils; + + +type + THashKeyMD5 = class + public + class function hash (const k: TMD5Digest): LongWord; inline; + class function equ (const a, b: TMD5Digest): Boolean; inline; + class procedure freekey (var k: TMD5Digest); inline; + end; + + THashStrCIInt = specialize THashBase; + THashMD5Int = specialize THashBase; + + TFileHashDB = class + private + type + TFileInfo = record + name: AnsiString; // names are relative to `mBasePath` + hash: TMD5Digest; + size: LongWord; + age: LongInt; + nextFree: Integer; + // used in directory scanner + wasSeen: Boolean; + end; + + private + mBasePath: AnsiString; // ends with '/' + mHash2List: THashMD5Int; // hash -> list index + mFile2List: THashStrCIInt; // file name -> list index + mFileList: array of TFileInfo; + mFreeHead: Integer; + + private + procedure removeIndex (idx: Integer); + function allocIndex (): Integer; + + procedure scanDir (path: AnsiString; var changed: Boolean); + + public + constructor Create (aBasePath: AnsiString); + destructor Destroy (); override; + + // doesn't clear base path + procedure clear (); + + // (re)scans base path and all its subdirs + // returns `true` if db was changed + // you'd better call it after loading a database + function scanFiles (): Boolean; + + // those throws + procedure saveTo (st: TStream); + // this clears existing data + procedure loadFrom (st: TStream); + + // returns file name relative to base path or empty string + function findByHash (const md5: TMD5Digest): AnsiString; + // returns `true` if something was changed + // name is relative to base + function addWithHash (relname: AnsiString; const md5: TMD5Digest): Boolean; + end; + + +implementation + + +class function THashKeyMD5.hash (const k: TMD5Digest): LongWord; inline; begin + //result := joaatHashPtr(@k, sizeof(TMD5Digest)); + //k8: use first 4 bytes of k as a hash instead? it should be good enough + Move(k, result, sizeof(result)); +end; +class function THashKeyMD5.equ (const a, b: TMD5Digest): Boolean; inline; begin result := MD5Match(a, b); end; +class procedure THashKeyMD5.freekey (var k: TMD5Digest); inline; begin end; + + +//========================================================================== +// +// fixSlashes +// +// fixes all slashes; adds a final one too +// +//========================================================================== +function fixSlashes (const path: AnsiString; addFinal: Boolean): AnsiString; +var + f: Integer; +begin + result := path; + for f := 1 to length(result) do if (result[f] = '\') then result[f] := '/'; + if (addFinal) and (length(result) > 0) and (result[length(result)] <> '/') then result := result+'/'; +end; + + +//========================================================================== +// +// TFileHashDB.Create +// +//========================================================================== +constructor TFileHashDB.Create (aBasePath: AnsiString); +begin + mBasePath := aBasePath; + if (length(aBasePath) <> 0) then + begin + if not findFileCI(mBasePath, true) then mBasePath := aBasePath; + end; + mBasePath := fixSlashes(mBasePath, true); + mHash2List := THashMD5Int.Create(); + mFile2List := THashStrCIInt.Create(); + SetLength(mFileList, 0); + mFreeHead := -1; +end; + + +//========================================================================== +// +// TFileHashDB.Destroy +// +//========================================================================== +destructor TFileHashDB.Destroy (); +begin + mBasePath := ''; + mHash2List.Free; + mFile2List.Free; + SetLength(mFileList, 0); + mFreeHead := -1; +end; + + +//========================================================================== +// +// TFileHashDB.clear +// +// doesn't clear base path +// +//========================================================================== +procedure TFileHashDB.clear (); +begin + mHash2List.clear(); + mFile2List.clear(); + SetLength(mFileList, 0); + mFreeHead := -1; +end; + + +//========================================================================== +// +// TFileHashDB.saveTo +// +//========================================================================== +procedure TFileHashDB.saveTo (st: TStream); +var + sign: array[0..3] of AnsiChar; + f: Integer; +begin + sign := 'FHDB'; + st.WriteBuffer(sign, 4); + st.WriteWord(0); // version + st.WriteDWord(LongWord(mFile2List.count)); + for f := Low(mFileList) to High(mFileList) do + begin + if (length(mFileList[f].name) = 0) then continue; + st.WriteAnsiString(mFileList[f].name); + st.WriteBuffer(mFileList[f].hash, sizeof(TMD5Digest)); + st.WriteDWord(mFileList[f].size); + st.WriteDWord(LongWord(mFileList[f].age)); + end; +end; + + +//========================================================================== +// +// TFileHashDB.loadFrom +// +//========================================================================== +procedure TFileHashDB.loadFrom (st: TStream); +var + sign: array[0..3] of AnsiChar; + count: Integer; + idx: Integer; + fi: ^TFileInfo; +begin + clear(); + try + st.ReadBuffer(sign, 4); + if (sign <> 'FHDB') then raise Exception.Create('invalid database signature'); + count := st.ReadWord(); + if (count <> 0) then raise Exception.Create('invalid database version'); + count := Integer(st.ReadDWord()); + if (count < 0) or (count > 1024*1024) then raise Exception.Create('invalid database file count'); + while (count > 0) do + begin + idx := allocIndex(); + fi := @mFileList[idx]; + fi.name := st.ReadAnsiString(); + st.ReadBuffer(fi.hash, sizeof(TMD5Digest)); + fi.size := st.ReadDWord(); + fi.age := Integer(st.ReadDWord()); + if (length(fi.name) = 0) then raise Exception.Create('invalid database file name'); + if (fi.age = -1) then raise Exception.Create('invalid database file age'); + mFile2List.put(fi.name, idx); + mHash2List.put(fi.hash, idx); + Dec(count); + end; + except + begin + clear(); + raise; + end; + end; +end; + + +//========================================================================== +// +// TFileHashDB.removeIndex +// +//========================================================================== +procedure TFileHashDB.removeIndex (idx: Integer); +begin + if (idx < 0) or (idx > High(mFileList)) or (length(mFileList[idx].name) = 0) then exit; // nothing to do + mFile2List.del(mFileList[idx].name); + mHash2List.del(mFileList[idx].hash); + mFileList[idx].name := ''; + mFileList[idx].nextFree := mFreeHead; + mFreeHead := idx; +end; + + +//========================================================================== +// +// TFileHashDB.allocIndex +// +//========================================================================== +function TFileHashDB.allocIndex (): Integer; +begin + result := mFreeHead; + if (result >= 0) then + begin + mFreeHead := mFileList[result].nextFree; + end + else + begin + result := length(mFileList); + SetLength(mFileList, length(mFileList)+1); // oooh... + end; +end; + + +//========================================================================== +// +// TFileHashDB.scanDir +// +//========================================================================== +procedure TFileHashDB.scanDir (path: AnsiString; var changed: Boolean); +var + sr: TSearchRec; + dfn: AnsiString; + hfn: AnsiString; + md5: TMD5Digest; + ok: Boolean; + idx: Integer; + age: LongInt; + needUpdate: Boolean; +begin + if (FindFirst(path+'*', faAnyFile, sr) <> 0) then exit; + try + repeat + if ((sr.Attr and faDirectory) <> 0) then + begin + // directory + if (sr.Name <> '.') and (sr.Name <> '..') then scanDir(path+sr.Name+'/', changed); + end + else if (hasWadExtension(sr.Name)) then + begin + // file + dfn := fixSlashes(path+sr.Name, false); + // build internal file name + hfn := dfn; + Delete(hfn, 1, length(mBasePath)); // remove prefix + // find file in hash + if not mFile2List.get(hfn, idx) then idx := -1; + // check if we already have this file + age := FileAge(dfn); + if (age <> -1) then + begin + // do we need to update this file? + if (idx >= 0) then + begin + needUpdate := + (age <> mFileList[idx].age) or + (LongWord(sr.size) <> mFileList[idx].size); + end + else + begin + needUpdate := true; + end; + // recalc md5 and update file entry, if necessary + if (needUpdate) then + begin + ok := false; + try + md5 := MD5File(dfn); + ok := true; + except + end; + if (ok) then + begin + changed := true; + // remove old hash -> index mapping + if (idx >= 0) then mHash2List.del(mFileList[idx].hash); + // update + if (idx < 0) then idx := allocIndex(); + mFileList[idx].name := hfn; + mFileList[idx].hash := md5; + mFileList[idx].size := LongWord(sr.size); + mFileList[idx].age := age; + mFileList[idx].nextFree := -1; + mFileList[idx].wasSeen := true; + mFile2List.put(hfn, idx); + mHash2List.put(md5, idx); + end + else + begin + // update failed, remove this entry + if (idx >= 0) then changed := true; + removeIndex(idx); // cannot read, remove + end; + end + else + begin + if (idx >= 0) then mFileList[idx].wasSeen := true; + end; + end + else + begin + // remove this file if we don't have it anymore + if (idx >= 0) then changed := true; + removeIndex(idx); + end; + end + else + begin + dfn := fixSlashes(path+sr.Name, false); + // build internal file name + hfn := dfn; + Delete(hfn, 1, length(mBasePath)); // remove prefix + // find file in hash + if mFile2List.get(hfn, idx) then + begin + changed := true; + removeIndex(idx); + end; + end; + until (FindNext(sr) <> 0); + finally + FindClose(sr); + end; +end; + + +//========================================================================== +// +// TFileHashDB.scanFiles +// +// scans base path and all its subdirs +// returns `true` if db was changed +// +//========================================================================== +function TFileHashDB.scanFiles (): Boolean; +var + f: Integer; +begin + result := false; + for f := Low(mFileList) to High(mFileList) do mFileList[f].wasSeen := false; + scanDir(mBasePath, result); + // remove all unseen files + f := High(mFileList); + while (f >= 0) do + begin + if (length(mFileList[f].name) > 0) and (not mFileList[f].wasSeen) then removeIndex(f); + Dec(f); + end; +end; + + +//========================================================================== +// +// TFileHashDB.findByHash +// +// returns file name relative to base path or empty string +// +//========================================================================== +function TFileHashDB.findByHash (const md5: TMD5Digest): AnsiString; +var + idx: Integer; +begin + if not mHash2List.get(md5, idx) then begin result := ''; exit; end; + result := mFileList[idx].name; +end; + + +//========================================================================== +// +// TFileHashDB.addWithHash +// +// returns `true` if something was changed +// name is relative to base +// +//========================================================================== +function TFileHashDB.addWithHash (relname: AnsiString; const md5: TMD5Digest): Boolean; +var + age: LongInt; + size: LongInt; + handle: THandle; + fn: AnsiString; + idx: Integer; +begin + result := false; + if (length(relname) > length(mBasePath)) and strEquCI1251(mBasePath, Copy(relname, 1, length(mBasePath))) then Delete(relname, 1, Length(mBasePath)); + if (length(relname) = 0) then exit; + fn := mBasePath+relname; + if not findFileCI(fn) then exit; + // get age + age := FileAge(fn); + if (age = -1) then exit; + // get size + handle := FileOpen(fn, fmOpenRead or fmShareDenyNone); + if (handle = THandle(-1)) then exit; + size := FileSeek(handle, 0, fsFromEnd); + FileClose(handle); + if (size = -1) then exit; + // find old file, if any + Delete(fn, 1, length(mBasePath)); + if not mFile2List.get(fn, idx) then idx := -1; + // check for changes + if (idx >= 0) then + begin + if (mFileList[idx].size = size) and (mFileList[idx].age = age) and (MD5Match(mFileList[idx].hash, md5)) then exit; + removeIndex(idx); + end; + idx := allocIndex(); + mFileList[idx].name := fn; + mFileList[idx].hash := md5; + mFileList[idx].size := size; + mFileList[idx].age := age; + mFileList[idx].nextFree := -1; + mFile2List.put(fn, idx); + mHash2List.put(md5, idx); + result := true; +end; + + +end.