On Mon, Jul 22, 2024 at 12:31:00AM -0400, George Koehler wrote:
> This diff adds sound to Mini vMac, with files/SGLUSNIO.h using sndio.
> 
> The emulator passes sound samples via MySound_BeginWrite and
> MySound_EndWrite to the X11 glue OSGLUXWN.c, which collects them into
> a ring of 16 buffers of 512 samples each.  The other sound glues (for
> ALSA and /dev/dsp) use non-blocking writes in a weird way.  I tried to
> use non-blocking writes for sndio, but that caused the sound to go
> silent after 3 seconds (at the 3rd call to MySound_SecondNotify).
> This diff uses blocking writes.
> 

For non-blocking writes to work, the caller must call poll(2) or an
equivalent to wake up when the device can accept data. I couldn't find
any poll(2) calls in the ALSA backend so I don't understand how writes
are triggered. Does it retry periodically? If so, you need to call
sio_pollfd(), poll(), sio_revents() before the non-blocking
sio_write().

Anyway, your diff looks right.

FWIW, the blocking sio_write() would likely block for at most one
block, which by default is 10ms.

> I have not contacted upstream.  When I do, I plan to change the
> license of files/GLUSNIO.h to Mini vMac's license.
> 
> Does it work?  Is it ok to commit?
> --gkoehler
> 
> Index: Makefile
> ===================================================================
> RCS file: /cvs/ports/emulators/minivmac/Makefile,v
> diff -u -p -r1.1.1.1 Makefile
> --- Makefile	18 Jul 2024 01:58:15 -0000	1.1.1.1
> +++ Makefile	22 Jul 2024 03:45:27 -0000
> @@ -2,6 +2,7 @@ ONLY_FOR_ARCHS =	i386 amd64 powerpc
>  
>  COMMENT =		early macintosh emulator
>  V =			36.04
> +REVISION =		0
>  DISTNAME =		minivmac-${V}
>  
>  CATEGORIES =		emulators
> @@ -10,7 +11,7 @@ HOMEPAGE = 		https://gryphel.com/c/miniv
>  
>  MAINTAINER =		Jag Talon <jag@aangat.lahat.computer>
>  
> -WANTLIB =		X11 c
> +WANTLIB =		X11 c sndio
>  
>  # GPLv2
>  PERMIT_PACKAGE =	Yes
> @@ -31,6 +32,9 @@ ALL_TARGET =		minivmac
>  SETUP_FLAGS-amd64 = 	-t ob64
>  SETUP_FLAGS-i386 = 	-t obsd
>  SETUP_FLAGS-powerpc = 	-t obsd -cpu ppc
> +
> +post-extract:
> +	cp ${FILESDIR}/SGLUSNIO.h ${WRKSRC}/src
>  
>  do-gen:
>  	cd ${WRKSRC}; cc setup/tool.c -o setup_t && \
> Index: files/SGLUSNIO.h
> ===================================================================
> RCS file: files/SGLUSNIO.h
> diff -N files/SGLUSNIO.h
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ files/SGLUSNIO.h	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,125 @@
> +/*
> + * Copyright (c) 2024 George Koehler <gkoehler@openbsd.org>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +/*
> +	Sound GLUe for SNdIO, https://man.openbsd.org/sio_open.3
> +*/
> +
> +LOCALVAR struct sio_hdl *audio_hdl;
> +LOCALVAR int audio_samples_pending;
> +
> +LOCALPROC MySound_Moved(void *arg, int delta)
> +{
> +	audio_samples_pending -= delta;
> +}
> +
> +LOCALPROC MySound_Start(void)
> +{
> +	if (audio_hdl) {
> +		MySound_Start0();
> +		audio_samples_pending = 0;
> +		sio_start(audio_hdl);
> +	}
> +}
> +
> +LOCALPROC MySound_Stop(void)
> +{
> +	if (audio_hdl) {
> +		sio_flush(audio_hdl);
> +	}
> +}
> +
> +LOCALFUNC blnr MySound_Init(void)
> +{
> +	struct sio_par par;
> +
> +	audio_hdl = sio_open(SIO_DEVANY, SIO_PLAY, 0 /* blocking */);
> +	if (audio_hdl == NULL) {
> +		fprintf(stderr, "Cannot open sndio.\n");
> +		return trueblnr;
> +	}
> +
> +	sio_initpar(&par);
> +	par.bits = 1 << kLn2SoundSampSz;
> +	par.sig = 0; /* unsigned samples */
> +	par.le = SIO_LE_NATIVE; /* byte order */
> +	par.pchan = 1;
> +	par.rate = SOUND_SAMPLERATE;
> +	par.round = kOneBuffLen;
> +	if (!sio_setpar(audio_hdl, &par) ||
> +		!sio_getpar(audio_hdl, &par) ||
> +		par.bits != 1 << kLn2SoundSampSz || par.sig != 0 ||
> +		par.le != SIO_LE_NATIVE || par.pchan != 1 ||
> +		par.rate < SOUND_SAMPLERATE * 995 / 1000 ||
> +		par.rate > SOUND_SAMPLERATE * 1005 / 1000)
> +	{
> +		fprintf(stderr, "Cannot set sndio parameters.\n");
> +		goto init_error;
> +	}
> +
> +	sio_onmove(audio_hdl, MySound_Moved, NULL);
> +	return trueblnr;
> +
> +init_error:
> +	sio_close(audio_hdl);
> +	audio_hdl = NULL;
> +	return trueblnr;
> +}
> +
> +LOCALPROC MySound_UnInit(void)
> +{
> +	if (audio_hdl) {
> +		sio_close(audio_hdl);
> +		audio_hdl = NULL;
> +	}
> +}
> +
> +GLOBALOSGLUPROC MySound_EndWrite(ui4r actL)
> +{
> +	tpSoundSamp PlayPtr;
> +	ui4b TotPendBuffs;
> +
> +	if (!MySound_EndWrite0(actL) || !audio_hdl) {
> +		return;
> +	}
> +
> +	/* sio_write will call MySound_Moved. */
> +	audio_samples_pending += kOneBuffLen;
> +
> +	/*
> +		Play one buffer (of kOneBuffSz bytes).
> +		Don't leave part of the buffer for later.
> +	*/
> +	PlayPtr = TheSoundBuffer + (ThePlayOffset & kAllBuffMask);
> +	if (sio_write(audio_hdl, PlayPtr, kOneBuffSz) != kOneBuffSz) {
> +		fprintf(stderr, "Error from sndio playing audio!\n");
> +		sio_close(audio_hdl);
> +		audio_hdl = NULL;
> +	}
> +	ThePlayOffset += kOneBuffLen;
> +
> +	TotPendBuffs = audio_samples_pending >> kLnOneBuffLen;
> +	if (TotPendBuffs < MinFilledSoundBuffs) {
> +		MinFilledSoundBuffs = TotPendBuffs;
> +	}
> +}
> +
> +LOCALPROC MySound_SecondNotify(void)
> +{
> +	if (audio_hdl) {
> +		MySound_SecondNotify0();
> +	}
> +}
> Index: patches/patch-setup_SPBLDOPT_i
> ===================================================================
> RCS file: patches/patch-setup_SPBLDOPT_i
> diff -N patches/patch-setup_SPBLDOPT_i
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-setup_SPBLDOPT_i	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,42 @@
> +- enable sndio on OpenBSD
> +
> +Index: setup/SPBLDOPT.i
> +--- setup/SPBLDOPT.i.orig
> ++++ setup/SPBLDOPT.i
> +@@ -542,7 +542,8 @@ LOCALFUNC blnr dfo_SoundEnabled(void)
> + 		|| ((gbk_apifam_xwn == gbo_apifam)
> + 			&& ((gbo_targfam == gbk_targfam_linx)
> + 				|| (gbo_targfam == gbk_targfam_fbsd)
> +-				|| (gbo_targfam == gbk_targfam_nbsd)));
> ++				|| (gbo_targfam == gbk_targfam_nbsd)
> ++				|| (gbo_targfam == gbk_targfam_obsd)));
> + 
> + 	return v;
> + }
> +@@ -568,6 +569,7 @@ enum {
> + 	gbk_sndapi_none,
> + 	gbk_sndapi_alsa,
> + 	gbk_sndapi_ddsp,
> ++	gbk_sndapi_sndio,
> + 	kNumSndApiLevels
> + };
> + 
> +@@ -594,6 +596,9 @@ LOCALFUNC char * GetSndApiName(int i)
> + 		case gbk_sndapi_ddsp:
> + 			s = "ddsp";
> + 			break;
> ++		case gbk_sndapi_sndio:
> ++			s = "sndio";
> ++			break;
> + 		default:
> + 			s = "(unknown sound api)";
> + 			break;
> +@@ -617,6 +622,8 @@ LOCALFUNC int dfo_sndapi(void)
> + 		v = gbk_sndapi_none;
> + 	} else if (gbo_targfam == gbk_targfam_linx) {
> + 		v = gbk_sndapi_alsa;
> ++	} else if (gbo_targfam == gbk_targfam_obsd) {
> ++		v = gbk_sndapi_sndio;
> + 	} else {
> + 		v = gbk_sndapi_ddsp;
> + 	}
> Index: patches/patch-setup_SPFILDEF_i
> ===================================================================
> RCS file: patches/patch-setup_SPFILDEF_i
> diff -N patches/patch-setup_SPFILDEF_i
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-setup_SPFILDEF_i	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,15 @@
> +- add sndio
> +
> +Index: setup/SPFILDEF.i
> +--- setup/SPFILDEF.i.orig
> ++++ setup/SPFILDEF.i
> +@@ -88,6 +88,9 @@ static void DoMYOSGLUEdepends(tDoOneDepends p)
> + 				case gbk_sndapi_ddsp:
> + 					s = "SGLUDDSP.h";
> + 					break;
> ++				case gbk_sndapi_sndio:
> ++					s = "SGLUSNIO.h";
> ++					break;
> + 			}
> + 
> + 			if (nullpr != s) {
> Index: patches/patch-setup_SPOTHRCF_i
> ===================================================================
> RCS file: patches/patch-setup_SPOTHRCF_i
> diff -N patches/patch-setup_SPOTHRCF_i
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-setup_SPOTHRCF_i	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,15 @@
> +- add sndio
> +
> +Index: setup/SPOTHRCF.i
> +--- setup/SPOTHRCF.i.orig
> ++++ setup/SPOTHRCF.i
> +@@ -555,6 +555,9 @@ LOCALPROC WriteAppSOUNDGLUcontents(void)
> + 		case gbk_sndapi_ddsp:
> + 			s = "DDSP";
> + 			break;
> ++		case gbk_sndapi_sndio:
> ++			s = "SNIO";
> ++			break;
> + 		default:
> + 			s = "???";
> + 			break;
> Index: patches/patch-setup_WRBGCFLS_i
> ===================================================================
> RCS file: patches/patch-setup_WRBGCFLS_i
> diff -N patches/patch-setup_WRBGCFLS_i
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-setup_WRBGCFLS_i	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,14 @@
> +- add sndio
> +
> +Index: setup/WRBGCFLS.i
> +--- setup/WRBGCFLS.i.orig
> ++++ setup/WRBGCFLS.i
> +@@ -357,6 +357,8 @@ LOCALPROC WriteBashGccMakeFile(void)
> + 					{
> + 						WriteCStrToDestFile(" -lossaudio");
> + 					}
> ++				} else if (gbk_sndapi_sndio == gbo_sndapi) {
> ++					WriteCStrToDestFile(" -lsndio");
> + 				}
> + #endif
> + #if 0
> Index: patches/patch-setup_WRCNFGAP_i
> ===================================================================
> RCS file: patches/patch-setup_WRCNFGAP_i
> diff -N patches/patch-setup_WRCNFGAP_i
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-setup_WRCNFGAP_i	22 Jul 2024 03:45:27 -0000
> @@ -0,0 +1,15 @@
> +- add sndio
> +
> +Index: setup/WRCNFGAP.i
> +--- setup/WRCNFGAP.i.orig
> ++++ setup/WRCNFGAP.i
> +@@ -194,6 +194,9 @@ LOCALPROC WriteCommonCNFGRAPIContents(void)
> + 						WriteDestFileLn("#include <sys/soundcard.h>");
> + 					}
> + 					break;
> ++				case gbk_sndapi_sndio:
> ++					WriteDestFileLn("#include <sndio.h>");
> ++					break;
> + 				default:
> + 					break;
> + 			}
> 
>