Mercurial > sdl-ios-xcode
view src/cdrom/macos/SDL_syscdrom.c @ 3880:74e828c64315 SDL-1.2
Fixed bug #292
I might be on crack here.
It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and
right channels of a stereo stream together, and clamps the new mono channel if
it would overflow.
Shouldn't it be dividing by 2 to average the two sample points instead of
clamping? Otherwise the mono sample point's volume doubles in the conversion.
This would also make the conversion faster, as it replaces two branches per
sample frame with a bitwise shift.
--ryan.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 24 Sep 2006 15:45:37 +0000 |
parents | 92947e3a18db |
children | 782fd950bd46 c121d94672cb a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" #ifdef SDL_CDROM_MACOS /* MacOS functions for system-level CD-ROM audio control */ #include <Devices.h> #include <Files.h> #include <LowMem.h> /* Use entry table macros, not functions in InterfaceLib */ #include "SDL_cdrom.h" #include "../SDL_syscdrom.h" #include "SDL_syscdrom_c.h" /* Added by Matt Slot */ #if !defined(LMGetUnitTableEntryCount) #define LMGetUnitTableEntryCount() *(short *)0x01D2 #endif /* The maximum number of CD-ROM drives we'll detect */ #define MAX_DRIVES 26 /* A list of available CD-ROM drives */ static long SDL_cdversion = 0; static struct { short dRefNum; short driveNum; long frames; char name[256]; Boolean hasAudio; } SDL_cdlist[MAX_DRIVES]; static StringPtr gDriverName = "\p.AppleCD"; /* The system-dependent CD control functions */ static const char *SDL_SYS_CDName(int drive); static int SDL_SYS_CDOpen(int drive); static int SDL_SYS_CDGetTOC(SDL_CD *cdrom); static CDstatus SDL_SYS_CDStatus(SDL_CD *cdrom, int *position); static int SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length); static int SDL_SYS_CDPause(SDL_CD *cdrom); static int SDL_SYS_CDResume(SDL_CD *cdrom); static int SDL_SYS_CDStop(SDL_CD *cdrom); static int SDL_SYS_CDEject(SDL_CD *cdrom); static void SDL_SYS_CDClose(SDL_CD *cdrom); static short SDL_SYS_ShortToBCD(short value) { return((value % 10) + (value / 10) * 0x10); /* Convert value to BCD */ } static short SDL_SYS_BCDToShort(short value) { return((value % 0x10) + (value / 0x10) * 10); /* Convert value from BCD */ } int SDL_SYS_CDInit(void) { SInt16 dRefNum = 0; SInt16 first, last; SDL_numcds = 0; /* Check that the software is available */ if (Gestalt(kGestaltAudioCDSelector, &SDL_cdversion) || !SDL_cdversion) return(0); /* Fill in our driver capabilities */ SDL_CDcaps.Name = SDL_SYS_CDName; SDL_CDcaps.Open = SDL_SYS_CDOpen; SDL_CDcaps.GetTOC = SDL_SYS_CDGetTOC; SDL_CDcaps.Status = SDL_SYS_CDStatus; SDL_CDcaps.Play = SDL_SYS_CDPlay; SDL_CDcaps.Pause = SDL_SYS_CDPause; SDL_CDcaps.Resume = SDL_SYS_CDResume; SDL_CDcaps.Stop = SDL_SYS_CDStop; SDL_CDcaps.Eject = SDL_SYS_CDEject; SDL_CDcaps.Close = SDL_SYS_CDClose; /* Walk the list, count each AudioCD driver, and save the refnums */ first = -1; last = 0 - LMGetUnitTableEntryCount(); for(dRefNum = first; dRefNum >= last; dRefNum--) { Str255 driverName; StringPtr namePtr; DCtlHandle deviceEntry; deviceEntry = GetDCtlEntry(dRefNum); if (! deviceEntry) continue; /* Is this an .AppleCD ? */ namePtr = (*deviceEntry)->dCtlFlags & (1L << dRAMBased) ? ((StringPtr) ((DCtlPtr) deviceEntry)->dCtlDriver + 18) : ((StringPtr) (*deviceEntry)->dCtlDriver + 18); BlockMoveData(namePtr, driverName, namePtr[0]+1); if (driverName[0] > gDriverName[0]) driverName[0] = gDriverName[0]; if (! EqualString(driverName, gDriverName, false, false)) continue; /* Record the basic info for each drive */ SDL_cdlist[SDL_numcds].dRefNum = dRefNum; BlockMoveData(namePtr + 1, SDL_cdlist[SDL_numcds].name, namePtr[0]); SDL_cdlist[SDL_numcds].name[namePtr[0]] = 0; SDL_cdlist[SDL_numcds].hasAudio = false; SDL_numcds++; } return(0); } static const char *SDL_SYS_CDName(int drive) { return(SDL_cdlist[drive].name); } static int get_drivenum(int drive) { QHdr *driveQ = GetDrvQHdr(); DrvQEl *driveElem; /* Update the drive number */ SDL_cdlist[drive].driveNum = 0; if ( driveQ->qTail ) { driveQ->qTail->qLink = 0; } for ( driveElem=(DrvQEl *)driveQ->qHead; driveElem; driveElem = (DrvQEl *)driveElem->qLink ) { if ( driveElem->dQRefNum == SDL_cdlist[drive].dRefNum ) { SDL_cdlist[drive].driveNum = driveElem->dQDrive; break; } } return(SDL_cdlist[drive].driveNum); } static int SDL_SYS_CDOpen(int drive) { return(drive); } static int SDL_SYS_CDGetTOC(SDL_CD *cdrom) { CDCntrlParam cdpb; CDTrackData tracks[SDL_MAX_TRACKS]; long i, leadout; /* Get the number of tracks on the CD by examining the TOC */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kReadTOC; cdpb.csParam.words[0] = kGetTrackRange; if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } cdrom->numtracks = SDL_SYS_BCDToShort(cdpb.csParam.bytes[1]) - SDL_SYS_BCDToShort(cdpb.csParam.bytes[0]) + 1; if ( cdrom->numtracks > SDL_MAX_TRACKS ) cdrom->numtracks = SDL_MAX_TRACKS; cdrom->status = CD_STOPPED; cdrom->cur_track = 0; /* Apparently these are set elsewhere */ cdrom->cur_frame = 0; /* Apparently these are set elsewhere */ /* Get the lead out area of the CD by examining the TOC */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kReadTOC; cdpb.csParam.words[0] = kGetLeadOutArea; if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } leadout = MSF_TO_FRAMES( SDL_SYS_BCDToShort(cdpb.csParam.bytes[0]), SDL_SYS_BCDToShort(cdpb.csParam.bytes[1]), SDL_SYS_BCDToShort(cdpb.csParam.bytes[2])); /* Get an array of track locations by examining the TOC */ SDL_memset(tracks, 0, sizeof(tracks)); SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kReadTOC; cdpb.csParam.words[0] = kGetTrackEntries; /* Type of Query */ * ((long *) (cdpb.csParam.words+1)) = (long) tracks; cdpb.csParam.words[3] = cdrom->numtracks * sizeof(tracks[0]); * ((char *) (cdpb.csParam.words+4)) = 1; /* First track */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } /* Read all the track TOC entries */ SDL_cdlist[cdrom->id].hasAudio = false; for ( i=0; i<cdrom->numtracks; ++i ) { cdrom->track[i].id = i+1; if (tracks[i].entry.control & kDataTrackMask) cdrom->track[i].type = SDL_DATA_TRACK; else { cdrom->track[i].type = SDL_AUDIO_TRACK; SDL_cdlist[SDL_numcds].hasAudio = true; } cdrom->track[i].offset = MSF_TO_FRAMES( SDL_SYS_BCDToShort(tracks[i].entry.min), SDL_SYS_BCDToShort(tracks[i].entry.min), SDL_SYS_BCDToShort(tracks[i].entry.frame)); cdrom->track[i].length = MSF_TO_FRAMES( SDL_SYS_BCDToShort(tracks[i+1].entry.min), SDL_SYS_BCDToShort(tracks[i+1].entry.min), SDL_SYS_BCDToShort(tracks[i+1].entry.frame)) - cdrom->track[i].offset; } /* Apparently SDL wants a fake last entry */ cdrom->track[i].offset = leadout; cdrom->track[i].length = 0; return(0); } /* Get CD-ROM status */ static CDstatus SDL_SYS_CDStatus(SDL_CD *cdrom, int *position) { CDCntrlParam cdpb; CDstatus status = CD_ERROR; Boolean spinning = false; if (position) *position = 0; /* Get the number of tracks on the CD by examining the TOC */ if ( ! get_drivenum(cdrom->id) ) { return(CD_TRAYEMPTY); } SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kReadTOC; cdpb.csParam.words[0] = kGetTrackRange; if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(CD_ERROR); } cdrom->numtracks = SDL_SYS_BCDToShort(cdpb.csParam.bytes[1]) - SDL_SYS_BCDToShort(cdpb.csParam.bytes[0]) + 1; if ( cdrom->numtracks > SDL_MAX_TRACKS ) cdrom->numtracks = SDL_MAX_TRACKS; cdrom->cur_track = 0; /* Apparently these are set elsewhere */ cdrom->cur_frame = 0; /* Apparently these are set elsewhere */ if (1 || SDL_cdlist[cdrom->id].hasAudio) { /* Get the current playback status */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioStatus; if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } switch(cdpb.csParam.cd.status) { case kStatusPlaying: status = CD_PLAYING; spinning = true; break; case kStatusPaused: status = CD_PAUSED; spinning = true; break; case kStatusMuted: status = CD_PLAYING; /* What should I do here? */ spinning = true; break; case kStatusDone: status = CD_STOPPED; spinning = true; break; case kStatusStopped: status = CD_STOPPED; spinning = false; break; case kStatusError: default: status = CD_ERROR; spinning = false; break; } if (spinning && position) *position = MSF_TO_FRAMES( SDL_SYS_BCDToShort(cdpb.csParam.cd.minute), SDL_SYS_BCDToShort(cdpb.csParam.cd.second), SDL_SYS_BCDToShort(cdpb.csParam.cd.frame)); } else status = CD_ERROR; /* What should I do here? */ return(status); } /* Start play */ static int SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length) { CDCntrlParam cdpb; /* Pause the current audio playback to avoid audible artifacts */ if ( SDL_SYS_CDPause(cdrom) < 0 ) { return(-1); } /* Specify the AudioCD playback mode */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kSetPlayMode; cdpb.csParam.bytes[0] = false; /* Repeat? */ cdpb.csParam.bytes[1] = kPlayModeSequential; /* Play mode */ /* ¥¥¥ÊTreat as soft error, NEC Drive doesnt support this call ¥¥¥ */ PBControlSync((ParmBlkPtr) &cdpb); #if 1 /* Specify the end of audio playback */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioStop; cdpb.csParam.words[0] = kBlockPosition; /* Position Mode */ *(long *) (cdpb.csParam.words + 1) = start+length-1; /* Search Address */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } /* Specify the start of audio playback, and start it */ SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioPlay; cdpb.csParam.words[0] = kBlockPosition; /* Position Mode */ *(long *) (cdpb.csParam.words + 1) = start+1; /* Search Address */ cdpb.csParam.words[3] = false; /* Stop address? */ cdpb.csParam.words[4] = kStereoPlayMode; /* Audio Play Mode */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } #else /* Specify the end of audio playback */ FRAMES_TO_MSF(start+length, &m, &s, &f); SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioStop; cdpb.csParam.words[0] = kTrackPosition; /* Position Mode */ cdpb.csParam.words[1] = 0; /* Search Address (hiword)*/ cdpb.csParam.words[2] = /* Search Address (loword)*/ SDL_SYS_ShortToBCD(cdrom->numtracks); if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } /* Specify the start of audio playback, and start it */ FRAMES_TO_MSF(start, &m, &s, &f); SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioPlay; cdpb.csParam.words[0] = kTrackPosition; /* Position Mode */ cdpb.csParam.words[1] = 0; /* Search Address (hiword)*/ cdpb.csParam.words[2] = SDL_SYS_ShortToBCD(1); /* Search Address (loword)*/ cdpb.csParam.words[3] = false; /* Stop address? */ cdpb.csParam.words[4] = kStereoPlayMode; /* Audio Play Mode */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } #endif return(0); } /* Pause play */ static int SDL_SYS_CDPause(SDL_CD *cdrom) { CDCntrlParam cdpb; SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioPause; cdpb.csParam.words[0] = 0; /* Pause/Continue Flag (hiword) */ cdpb.csParam.words[1] = 1; /* Pause/Continue Flag (loword) */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } return(0); } /* Resume play */ static int SDL_SYS_CDResume(SDL_CD *cdrom) { CDCntrlParam cdpb; SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioPause; cdpb.csParam.words[0] = 0; /* Pause/Continue Flag (hiword) */ cdpb.csParam.words[1] = 0; /* Pause/Continue Flag (loword) */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } return(0); } /* Stop play */ static int SDL_SYS_CDStop(SDL_CD *cdrom) { CDCntrlParam cdpb; SDL_memset(&cdpb, 0, sizeof(cdpb)); cdpb.ioVRefNum = SDL_cdlist[cdrom->id].driveNum; cdpb.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cdpb.csCode = kAudioStop; cdpb.csParam.words[0] = 0; /* Position Mode */ cdpb.csParam.words[1] = 0; /* Search Address (hiword) */ cdpb.csParam.words[2] = 0; /* Search Address (loword) */ if ( PBControlSync((ParmBlkPtr)&cdpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } return(0); } /* Eject the CD-ROM */ static int SDL_SYS_CDEject(SDL_CD *cdrom) { Boolean disk = false; QHdr *driveQ = GetDrvQHdr(); DrvQEl *driveElem; HParamBlockRec hpb; ParamBlockRec cpb; for ( driveElem = (DrvQEl *) driveQ->qHead; driveElem; driveElem = (driveElem) ? ((DrvQEl *) driveElem->qLink) : ((DrvQEl *) driveQ->qHead) ) { if ( driveQ->qTail ) { driveQ->qTail->qLink = 0; } if ( driveElem->dQRefNum != SDL_cdlist[cdrom->id].dRefNum ) { continue; } /* Does drive contain mounted volume? If not, skip */ SDL_memset(&hpb, 0, sizeof(hpb)); hpb.volumeParam.ioVRefNum = driveElem->dQDrive; if ( PBHGetVInfoSync(&hpb) != noErr ) { continue; } if ( (UnmountVol(0, driveElem->dQDrive) == noErr) && (Eject(0, driveElem->dQDrive) == noErr) ) { driveElem = 0; /* Clear pointer to reset our loop */ disk = true; } } /* If no disk is present, just eject the tray */ if (! disk) { SDL_memset(&cpb, 0, sizeof(cpb)); cpb.cntrlParam.ioVRefNum = 0; /* No Drive */ cpb.cntrlParam.ioCRefNum = SDL_cdlist[cdrom->id].dRefNum; cpb.cntrlParam.csCode = kEjectTheDisc; if ( PBControlSync((ParmBlkPtr)&cpb) != noErr ) { SDL_SetError("PBControlSync() failed"); return(-1); } } return(0); } /* Close the CD-ROM handle */ static void SDL_SYS_CDClose(SDL_CD *cdrom) { return; } void SDL_SYS_CDQuit(void) { while(SDL_numcds--) SDL_memset(SDL_cdlist + SDL_numcds, 0, sizeof(SDL_cdlist[0])); } #endif /* SDL_CDROM_MACOS */