Mercurial > sdl-ios-xcode
view src/timer/mint/SDL_vbltimer.S @ 773:da0a2ad35bf4
Date: Sun, 4 Jan 2004 23:48:19 +0100
From: Max Horn
Subject: Re: Again Audio CD patch
Am 04.01.2004 um 22:38 schrieb Sam Lantinga:
>
> Okay, I fixed the buffering problems by simply using a 4 second buffer
> instead of a 1 second buffer. However, using your code I can't play an
> entire CD - the playback stops after the first song.
>
Found the problem: FSReadFork returns eofErr when the file is finished.
However, we check its return value for errors, and if anything but
noErr occurs, the reader thread aborts its current iteration. That is
bad, because it aborts before it can ever set the flag which tells that
the file is over (also, any remaining data which FSRead did return is
lost - so you'd not hear about to 4 seconds from the end of the file.
Furthermore, the computed data size was 8 bytes to high (I forgot to
account for the fact that the size of an (A)IFF chunk always contains
the chunk header & size fields, too). This is enough to make it work.
However, the end condition is rather fragile, so I tuned some other
things to be pessimistic (check for <= 0 instead of == 0, when eofErr
is encountered enforce mReadFilePosition == mFileLength). You never
know...
The attached patch fixes the issue for me.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Mon, 05 Jan 2004 00:57:51 +0000 |
| parents | f6ffac90895c |
| children | c9b51268668f |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif /* * VBL queue routine * * Patrice Mandin */ #define _vbl_queue 0x456 .text .globl _SDL_AtariVblInstall .globl _SDL_AtariVblUninstall /*--- Vector installer ---*/ _SDL_AtariVblInstall: movel sp@(4),my_vector lea _my_vbl,a0 clrw vbl_mutex /* Stop interrupts */ movew #0x2700,sr /* Read vbl_queue pointer */ movel _vbl_queue.w,a1 /* Search a free place */ moveq #7,d0 bcl_search_place: movel (a1),d1 beqs place_found addql #4,a1 dbra d0,bcl_search_place /* Not found */ moveq #1,d0 bras exit_vbl_queue /* Then install ourselves */ place_found: movel a0,(a1) moveq #0,d0 exit_vbl_queue: /* Restart interrupts */ movew #0x2300,sr rts /*--- Vector uninstaller ---*/ _SDL_AtariVblUninstall: movel sp@(4),d0 cmpl my_vector,d0 bnes badvector movel #_my_vbl,d0 /* Stop interrupts */ movew #0x2700,sr /* Read vbl_queue pointer */ movel _vbl_queue.w,a1 /* Search where we are */ moveq #7,d1 bcl2_search_place: cmpl (a1),d0 bnes next_place clrl (a1) moveq #0,d1 next_place: addql #4,a1 dbra d1,bcl2_search_place /* Restart interrupts */ movew #0x2300,sr badvector: rts /*--- Our vbl ---*/ _my_vbl: /* Verify if this is not already running */ tstw vbl_mutex bnes vbl_end notw vbl_mutex moveml d0-d7/a0-a6,sp@- movel my_vector,a0 jsr a0@ moveml sp@+,d0-d7/a0-a6 clrw vbl_mutex vbl_end: rts .data .even .comm vbl_mutex,2*1 .even .comm my_vector,4*1