Mercurial > sdl-ios-xcode
view test/testcdrom.c @ 4216:5b99971a27b4 SDL-1.2
Fixed bug #698
Hans de Goede 2009-02-13 01:10:52 PST
Since the new "glitch free" version of pulseaudio (used in Fedora 10 amongst
others), the sound of SDL using apps (like a simple playmus call) has been
crackling.
While looking in to fixing this I noticed that the current pulseaudio code in
SDL uses pa_simple. However pa_simple uses a thread to pump pulseaudio events
and ipc, given that SDL already has its own thread for audio handling this is
clearly suboptimal, leading to unnecessary context switching IPC, etc. Also
pa_simple does not allow one to implement the WaitAudio() callback for SDL
audiodrivers properly.
Given that my work is mostly a rewrite (although some original pieces remain)
I'm attaching the new .c and .h file, as that is easier to review then the huge
diff.
Let me know if you also want the diff.
This new version has the following features:
-no longer use an additional thread next to the SDL sound thread
-do not crackle with glitch free audio
-when used with a newer pulse, which does glitch free audio, the total latency
is
the same as with the alsa driver
-proper WaitAudio() implementation, saving another mixlen worth of latency
-adds a WaitDone() implementation
This patch has been written in consultancy with Lennart Poetering (the
pulseaudio author) and has been reviewed by him for correct use of the pa API.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 21 Sep 2009 09:27:08 +0000 |
parents | b2b476a4a73c |
children | 782fd950bd46 c121d94672cb |
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/* Test the SDL CD-ROM audio functions */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <ctype.h> #include "SDL.h" /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ static void quit(int rc) { SDL_Quit(); exit(rc); } static void PrintStatus(int driveindex, SDL_CD *cdrom) { CDstatus status; char *status_str; status = SDL_CDStatus(cdrom); switch (status) { case CD_TRAYEMPTY: status_str = "tray empty"; break; case CD_STOPPED: status_str = "stopped"; break; case CD_PLAYING: status_str = "playing"; break; case CD_PAUSED: status_str = "paused"; break; case CD_ERROR: status_str = "error state"; break; } printf("Drive %d status: %s\n", driveindex, status_str); if ( status >= CD_PLAYING ) { int m, s, f; FRAMES_TO_MSF(cdrom->cur_frame, &m, &s, &f); printf("Currently playing track %d, %d:%2.2d\n", cdrom->track[cdrom->cur_track].id, m, s); } } static void ListTracks(SDL_CD *cdrom) { int i; int m, s, f; char* trtype; SDL_CDStatus(cdrom); printf("Drive tracks: %d\n", cdrom->numtracks); for ( i=0; i<cdrom->numtracks; ++i ) { FRAMES_TO_MSF(cdrom->track[i].length, &m, &s, &f); if ( f > 0 ) ++s; switch(cdrom->track[i].type) { case SDL_AUDIO_TRACK: trtype="audio"; break; case SDL_DATA_TRACK: trtype="data"; break; default: trtype="unknown"; break; } printf("\tTrack (index %d) %d: %d:%2.2d / %d [%s track]\n", i, cdrom->track[i].id, m, s, cdrom->track[i].length, trtype); } } static void PrintUsage(char *argv0) { fprintf(stderr, "Usage: %s [drive#] [command] [command] ...\n", argv0); fprintf(stderr, "Where 'command' is one of:\n"); fprintf(stderr, " -status\n"); fprintf(stderr, " -list\n"); fprintf(stderr, " -play [first_track] [first_frame] [num_tracks] [num_frames]\n"); fprintf(stderr, " -pause\n"); fprintf(stderr, " -resume\n"); fprintf(stderr, " -stop\n"); fprintf(stderr, " -eject\n"); fprintf(stderr, " -sleep <milliseconds>\n"); } int main(int argc, char *argv[]) { int drive; int i; SDL_CD *cdrom; /* Initialize SDL first */ if ( SDL_Init(SDL_INIT_CDROM) < 0 ) { fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError()); return(1); } /* Find out how many CD-ROM drives are connected to the system */ if ( SDL_CDNumDrives() == 0 ) { printf("No CD-ROM devices detected\n"); quit(0); } printf("Drives available: %d\n", SDL_CDNumDrives()); for ( i=0; i<SDL_CDNumDrives(); ++i ) { printf("Drive %d: \"%s\"\n", i, SDL_CDName(i)); } /* Open the CD-ROM */ drive = 0; i=1; if ( argv[i] && isdigit(argv[i][0]) ) { drive = atoi(argv[i++]); } cdrom = SDL_CDOpen(drive); if ( cdrom == NULL ) { fprintf(stderr, "Couldn't open drive %d: %s\n", drive, SDL_GetError()); quit(2); } #ifdef TEST_NULLCD cdrom = NULL; #endif /* Find out which function to perform */ for ( ; argv[i]; ++i ) { if ( strcmp(argv[i], "-status") == 0 ) { /* PrintStatus(drive, cdrom); */ } else if ( strcmp(argv[i], "-list") == 0 ) { ListTracks(cdrom); } else if ( strcmp(argv[i], "-play") == 0 ) { int strack, sframe; int ntrack, nframe; strack = 0; if ( argv[i+1] && isdigit(argv[i+1][0]) ) { strack = atoi(argv[++i]); } sframe = 0; if ( argv[i+1] && isdigit(argv[i+1][0]) ) { sframe = atoi(argv[++i]); } ntrack = 0; if ( argv[i+1] && isdigit(argv[i+1][0]) ) { ntrack = atoi(argv[++i]); } nframe = 0; if ( argv[i+1] && isdigit(argv[i+1][0]) ) { nframe = atoi(argv[++i]); } if ( CD_INDRIVE(SDL_CDStatus(cdrom)) ) { if ( SDL_CDPlayTracks(cdrom, strack, sframe, ntrack, nframe) < 0 ) { fprintf(stderr, "Couldn't play tracks %d/%d for %d/%d: %s\n", strack, sframe, ntrack, nframe, SDL_GetError()); } } else { fprintf(stderr, "No CD in drive!\n"); } } else if ( strcmp(argv[i], "-pause") == 0 ) { if ( SDL_CDPause(cdrom) < 0 ) { fprintf(stderr, "Couldn't pause CD: %s\n", SDL_GetError()); } } else if ( strcmp(argv[i], "-resume") == 0 ) { if ( SDL_CDResume(cdrom) < 0 ) { fprintf(stderr, "Couldn't resume CD: %s\n", SDL_GetError()); } } else if ( strcmp(argv[i], "-stop") == 0 ) { if ( SDL_CDStop(cdrom) < 0 ) { fprintf(stderr, "Couldn't eject CD: %s\n", SDL_GetError()); } } else if ( strcmp(argv[i], "-eject") == 0 ) { if ( SDL_CDEject(cdrom) < 0 ) { fprintf(stderr, "Couldn't eject CD: %s\n", SDL_GetError()); } } else if ( (strcmp(argv[i], "-sleep") == 0) && (argv[i+1] && isdigit(argv[i+1][0])) ) { SDL_Delay(atoi(argv[++i])); printf("Delayed %d milliseconds\n", atoi(argv[i])); } else { PrintUsage(argv[0]); SDL_CDClose(cdrom); quit(1); } } PrintStatus(drive, cdrom); SDL_CDClose(cdrom); SDL_Quit(); return(0); }