src/engine/e_soundfile_mp3.pas

   1 (* Copyright (C)  Doom 2D: Forever Developers
   2  *
   3  * This program is free software: you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation, either version 3 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *)
  16 {$INCLUDE ../shared/a_modes.inc}
  17 unit e_soundfile_mp3;
  18
  19 interface
  20
  21 uses e_soundfile, mpg123, classes;
  22
  23 type
  24   // an MP3 loader that uses libmpg123
  25
  26   TMP3Loader = class (TSoundLoader)
  27   public
  28     function Load(Data: Pointer; Len: LongWord; SStreaming: Boolean): Boolean; override; overload;
  29     function Load(FName: string; SStreaming: Boolean): Boolean; override; overload;
  30     function SetPosition(Pos: LongWord): Boolean; override;
  31     function FillBuffer(Buf: Pointer; Len: LongWord): LongWord; override;
  32     function GetAll(var OutPtr: Pointer): LongWord; override;
  33     procedure Free(); override;
  34
  35   private
  36     FMPG: pmpg123_handle;
  37     FData: TStream;
  38     FBuf: Pointer;
  39     FAllSamples: Pointer;
  40     FOpen: Boolean;
  41
  42     function LoadStream(Stream: TStream; SStreaming: Boolean): Boolean;
  43   end;
  44
  45   TMP3LoaderFactory = class (TSoundLoaderFactory)
  46   public
  47     constructor Create();
  48     destructor Destroy(); override;
  49     function MatchHeader(Data: Pointer; Len: LongWord): Boolean; override;
  50     function MatchExtension(FName: string): Boolean; override;
  51     function GetLoader(): TSoundLoader; override;
  52   private
  53     FMPG: pmpg123_handle; // tester context
  54   end;
  55
  56 implementation
  57
  58 uses sysutils, utils, e_sound, e_log, ctypes, xstreams;
  59
  60 (* Reader functions for mpg123_replace_reader_handle *)
  61
  62 function streamLSeek(h: Pointer; off: coff_t; whence: cint): coff_t; cdecl;
  63 var
  64   S: TStream;
  65 begin
  66   S:= TStream(h);
  67   try
  68     case whence of
  69       0: Result := s.Seek(off, soBeginning); // SEEK_SET
  70       1: Result := s.Seek(off, soCurrent);   // SEEK_CUR
  71       2: Result := s.Seek(off, soEnd);       // SEEK_END
  72     end;
  73   except
  74     Result := -1;
  75   end;
  76 end;
  77
  78 function streamRead(h: Pointer; buf: Pointer; len: csize_t): csize_t; cdecl; // ssize_t
  79 var
  80   S: TStream;
  81 begin
  82   S:= TStream(h);
  83   try
  84     Result := S.Read(buf^, len);
  85   except
  86     Result := csize_t(-1);
  87   end;
  88 end;
  89
  90 (* TMP3LoaderFactory *)
  91
  92 constructor TMP3LoaderFactory.Create();
  93 begin
  94   FMPG := mpg123_new(nil, nil);
  95   if FMPG <> nil then
  96     mpg123_replace_reader_handle(FMPG, streamRead, streamLSeek, nil);
  97 end;
  98
  99 destructor TMP3LoaderFactory.Destroy();
 100 begin
 101   if FMPG <> nil then mpg123_delete(FMPG);
 102 end;
 103
 104 function TMP3LoaderFactory.MatchHeader(Data: Pointer; Len: LongWord): Boolean;
 105 var
 106   ID3: array [0..9] of Byte;
 107   HeaderLen: LongInt;
 108   S: TSFSMemoryStreamRO;
 109   Info: mpg123_frameinfo;
 110 begin
 111   Result := False;
 112   if Len < 10 then Exit;
 113
 114   // try and check for an ID3 header
 115   Move(Data^, ID3, 10);
 116   if (ID3[0] = Ord('I')) and (ID3[1] = Ord('D')) and (ID3[2] = Ord('3')) then
 117   begin
 118     HeaderLen := ID3[9] + (ID3[8] shl 7) + (ID3[7] shl 14) + (ID3[6] shl 21);
 119     Result := Len > (HeaderLen + 10);
 120     if Result then Exit;
 121   end;
 122
 123   // if there isn't one, employ heavier shit
 124   if FMPG = nil then Exit;
 125
 126   S := TSFSMemoryStreamRO.Create(Data, Len);
 127
 128   if mpg123_open_handle(FMPG, S) = MPG123_OK then
 129   begin
 130     Result := mpg123_info(FMPG, @Info) = MPG123_OK;
 131     mpg123_close(FMPG);
 132   end;
 133
 134   S.Destroy();
 135 end;
 136
 137 function TMP3LoaderFactory.MatchExtension(FName: string): Boolean;
 138 var
 139   Ext: string;
 140 begin
 141   Ext := GetFilenameExt(FName);
 142   Result := (Ext = '.mp3') or (Ext = '.mpeg3');
 143 end;
 144
 145 function TMP3LoaderFactory.GetLoader(): TSoundLoader;
 146 begin
 147   Result := TMP3Loader.Create();
 148 end;
 149
 150 (* TMP3Loader *)
 151
 152 function TMP3Loader.LoadStream(Stream: TStream; SStreaming: Boolean): Boolean;
 153 var
 154   SRate, SEnc, SChans: LongInt;
 155 begin
 156   FMPG := mpg123_new(nil, nil);
 157   if FMPG = nil then
 158   begin
 159     e_LogWriteln('MPG123: mpg123_new() failed');
 160     Exit;
 161   end;
 162
 163   try
 164     if mpg123_replace_reader_handle(FMPG, streamRead, streamLSeek, nil) <> MPG123_OK then
 165       raise Exception.Create('mpg123_replace_header_handle failed');
 166     if mpg123_open_handle(FMPG, Stream) <> MPG123_OK then
 167       raise Exception.Create('mpg123_open_handle failed');
 168
 169     FOpen := True;
 170
 171     if mpg123_getformat(FMPG, @SRate, @SChans, @SEnc) <> MPG123_OK then
 172       raise Exception.Create('mpg123_get_format failed');
 173     if (SChans < 1) or (SChans > 2) or (SRate <= 0) then
 174       raise Exception.Create('invalid format');
 175
 176     mpg123_format_none(FMPG);
 177     if mpg123_format(FMPG, SRate, SChans, MPG123_ENC_SIGNED_16) <> MPG123_OK then
 178       raise Exception.Create('mpg123_format failed');
 179   except
 180     on E: Exception do
 181     begin
 182       e_LogWriteln('MPG123: Load(Data) failed: ' + E.Message);
 183       if FOpen then mpg123_close(FMPG);
 184       mpg123_delete(FMPG);
 185       FMPG := nil;
 186       FOpen := False;
 187       Exit;
 188     end;
 189   end;
 190
 191   FData := Stream;
 192   FFormat.SampleRate := SRate;
 193   FFormat.SampleBits := 16;
 194   FFormat.Channels := SChans;
 195   FStreaming := SStreaming;
 196
 197   Result := True;
 198 end;
 199
 200 function TMP3Loader.Load(Data: Pointer; Len: LongWord; SStreaming: Boolean): Boolean;
 201 var
 202   S: TStream;
 203 begin
 204   Result := False;
 205
 206   // TODO: have to make a dupe here because Data gets deallocated after loading
 207   //       this is obviously very shit
 208   FBuf := GetMem(Len);
 209   if FBuf = nil then Exit;
 210   Move(Data^, FBuf^, Len);
 211
 212   S := TSFSMemoryStreamRO.Create(FBuf, Len{, True});
 213   Result := LoadStream(S, SStreaming);
 214
 215   if not Result and (S <> nil) then
 216   begin
 217     S.Destroy();
 218     FreeMem(FBuf);
 219     FBuf := nil;
 220   end;
 221 end;
 222
 223 function TMP3Loader.Load(FName: string; SStreaming: Boolean): Boolean;
 224 var
 225   S: TStream = nil;
 226 begin
 227   Result := False;
 228
 229   try
 230     S := openDiskFileRO(FName);
 231     Result := LoadStream(S, SStreaming);
 232   except
 233     on E: Exception do
 234       e_LogWritefln('ModPlug: ERROR: could not read file `%s`: %s', [FName, E.Message]);
 235   end;
 236
 237   if not Result and (S <> nil) then
 238     S.Destroy();
 239 end;
 240
 241 function TMP3Loader.SetPosition(Pos: LongWord): Boolean;
 242 begin
 243   Result := False;
 244   if FMPG = nil then Exit;
 245   Result := mpg123_seek(FMPG, Pos, 0) = MPG123_OK;
 246 end;
 247
 248 function TMP3Loader.FillBuffer(Buf: Pointer; Len: LongWord): LongWord;
 249 var
 250   Ret: LongInt;
 251   Got: csize_t;
 252 begin
 253   Result := 0;
 254   Got := 0;
 255   if FMPG = nil then Exit;
 256   Ret := mpg123_read(FMPG, Buf, Len, @Got);
 257   if FLooping and (Ret = MPG123_DONE) then
 258     mpg123_seek(FMPG, 0, 0); // loop
 259   Result := Got;
 260 end;
 261
 262 function TMP3Loader.GetAll(var OutPtr: Pointer): LongWord;
 263 begin
 264   Result := 0;
 265   if FMPG = nil then Exit;
 266   if FStreaming then Exit;
 267   // TODO
 268 end;
 269
 270 procedure TMP3Loader.Free();
 271 begin
 272   if FOpen then mpg123_close(FMPG);
 273   if FMPG <> nil then mpg123_delete(FMPG);
 274   if FData <> nil then FData.Destroy();
 275   if FBuf <> nil then FreeMem(FBuf);
 276   if FAllSamples <> nil then FreeMem(FAllSamples);
 277   FOpen := False;
 278   FMPG := nil;
 279   FData := nil;
 280   FBuf := nil;
 281   FAllSamples := nil;
 282 end;
 283
 284 initialization
 285   if mpg123_init() = MPG123_OK then
 286     e_AddSoundLoader(TMP3LoaderFactory.Create());
 287 finalization
 288   mpg123_exit();
 289 end.