-Add: add Open Sound System (OSS) support

OSS is the prefered sound API under FreeBSD
ALSA is prefered under Linux

config.lib

@@ -42,6 +42,7 @@ set_default() {
 	with_sdlimage="1"
 	with_sdl2="1"
 	with_asound="1"
+	with_oss="1"
 	with_pulse="1"
 	with_munt="1"
 	enable_builtin_depend="1"
@@ -79,6 +80,7 @@ set_default() {
 		with_sdlimage
 		with_sdl2
 		with_asound
+		with_oss
 		with_pulse
 		with_munt
 		enable_builtin_depend
@@ -188,6 +190,9 @@ detect_params() {
 			--without-alsa)               with_asound="0";;
 			--with-alsa=*)                with_asound="$optarg";;
 
+			--with-oss)                   with_oss="2";;
+			--without-oss)                with_oss="0";;
+
 			--with-pulse)                 with_pulse="2";;
 			--without-pulse)              with_pulse="0";;
 			--with-pulse=*)               with_pulse="$optarg";;
@@ -439,9 +444,14 @@ check_params() {
 		with_sdl2="0"
 		with_sdl="0"
 		with_asound="0"
+		with_oss="0"
 		with_pulse="0"
 		with_munt="0"
 	fi
+	if [ "$os" = "FREEBSD" ] && [ "$with_oss" != "0" ] && [ "$with_asound" = "1" ] ; then
+		# prefers OSS to ALSA under FreeBSD
+		with_asound="0"
+	fi
 	detect_sdl2
 	detect_sdl
 	detect_asound
@@ -2037,6 +2047,7 @@ showhelp() {
 	echo "  --with-sdl[=sdl-config]        enables SDL video driver support"
 	echo "  --with-sdl2[=sdl2-config]      enables SDL2 video driver support"
 	echo "  --with-asound[=libasound.a]    enables ALSA support"
+	echo "  --with-oss                     enables Open Sound System"
 	echo "  --with-munt                    enables MUNT support"
 	echo "  --with-pulse[=libpulse.a]      enables PulseAudio support"
 	echo "  --disable-builtin-depend       disable use of builtin deps finder"

configure

@@ -95,7 +95,8 @@ AWKCOMMAND='
 		if ($0 == "SDL2"        && "'$sdl2_config'" == "")         { next; }
 		if ($0 == "SDL"         && "'$sdl_config'" == "")          { next; }
 		if ($0 == "ALSA"        && "'$with_asound'" == "0")        { next; }
-		if ($0 == "MUNT"        && "'$with_munt'" == "0")        { next; }
+		if ($0 == "OSS"         && "'$with_oss'" == "0")           { next; }
+		if ($0 == "MUNT"        && "'$with_munt'" == "0")          { next; }
 		if ($0 == "PULSE"       && "'$with_pulse'" == "0")         { next; }
 		if ($0 == "OSX"         && "'$os'" != "OSX")               { next; }
 		if ($0 == "TOS"         && "'$os'" != "TOS")               { next; }

source.list

@@ -16,6 +16,9 @@ audio/midi_atari.c
 	#else
 		#if ALSA
 			audio/dsp_alsa.c
+		#else
+		#if OSS
+			audio/dsp_oss.c
 		#else
 			#if SDL
 				audio/dsp_sdl.c
@@ -27,6 +30,7 @@ audio/midi_atari.c
 				#endif
 			#endif
 		#endif
+		#endif
 	#endif
 # MIDI
 	#if MUNT

src/audio/dsp_oss.c

@@ -0,0 +1,160 @@
+/** @file src/audio/dsp_oss.c OSS (Open Sound System) implementation of the DSP. */
+/* OSS is deprecated under linux, but still used in *BSD world */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/soundcard.h>
+#include "types.h"
+#include "../timer.h"
+#include "../os/error.h"
+#include "../os/endian.h"
+
+#include "dsp.h"
+
+#define AUDIO_DEVICE "/dev/dsp"
+
+static void oss_tick(void);
+
+static int s_oss_fd = -1;
+
+static const uint8 * s_data_to_play = NULL;
+static size_t s_bytes_to_play = 0;
+
+void DSP_Stop(void)
+{
+	if(s_oss_fd >= 0) {
+		close(s_oss_fd);
+		s_oss_fd = -1;
+	}
+}
+
+void DSP_Uninit(void)
+{
+	DSP_Stop();
+	Timer_Remove(oss_tick);
+}
+
+bool DSP_Init(void)
+{
+	s_oss_fd = open(AUDIO_DEVICE, O_WRONLY);
+	if(s_oss_fd < 0) {
+		Error("DSP_Init() OSS : open(%s) : %s\n", AUDIO_DEVICE, strerror(errno));
+		return false;
+	}
+#ifdef SNDCTL_SYSINFO
+	{
+		struct oss_sysinfo info;
+		if(ioctl(s_oss_fd, SNDCTL_SYSINFO, &info) < 0) {
+			Warning("ioctl(SNDCTL_SYSINFO) Failed : %s\n", strerror(errno));
+		} else {
+			Debug("DSP_Init() : %s version %s %d dsp devices\n",
+			      info.product, info.version, info.numaudios);
+		}
+	}
+#endif
+	close(s_oss_fd);
+	s_oss_fd = -1;
+	Timer_Add(oss_tick, 1000000 / 10, true);
+	return true;
+}
+
+void DSP_Play(const uint8 *data)
+{
+	int i;
+	uint32 len;
+	int freq;
+	ssize_t n;
+
+	DSP_Stop();
+
+	data += READ_LE_UINT16(data + 20);	/* skip Create Voice File header */
+
+	/* first byte is Block Type :
+	 * 0x00: Terminator
+	 * 0x01: Sound data
+	 * 0x02: Sound data continuation
+	 * 0x03: Silence
+	 * 0x04: Marker
+	 * 0x05: Text
+	 * 0x06: Repeat start
+	 * 0x07: Repeat end
+	 * 0x08: Extra info
+	 * 0x09: Sound data (New format) */
+	if (*data != 1) return;
+
+	/* next 3 bytes are block size (not including the 1 block type and size 4 bytes) */
+	len = (READ_LE_UINT32(data) >> 8) - 2;
+	data += 4;
+	/* byte  0    frequency divisor
+	 * byte  1    codec id : 0 is "8bits unsigned PCM"
+	 * bytes 2..n audio data */
+
+	freq = 1000000 / (256 - data[0]);
+	if (data[1] != 0) Warning("Unsupported VOC codec 0x%02x\n", (int)data[1]);
+
+	s_oss_fd = open(AUDIO_DEVICE, O_WRONLY);
+	if(s_oss_fd < 0) {
+		Error("open(%s) : %s\n", AUDIO_DEVICE, strerror(errno));
+		return;
+	}
+	i = AFMT_U8;	/* Unsigned 8bit samples */
+	if(ioctl(s_oss_fd, SNDCTL_DSP_SETFMT, &i) < 0) {
+		Error("Failed to set unsigned 8bit format\n");
+	}
+	i = 0;	/* MONO */
+	if(ioctl(s_oss_fd, SNDCTL_DSP_STEREO, &i) < 0) {
+		Error("Failed to set mono\n");
+	}
+	/*Debug("Setting sample rate = %d\n", freq);*/
+	if(ioctl(s_oss_fd, SNDCTL_DSP_SPEED, &freq) < 0) {
+		Error("Failed to set sample rate\n");
+	}
+	/*Debug("Real sample rate = %d\n", freq);*/
+
+	n = write(s_oss_fd, data + 2, len);
+	Debug("write() returned %d (len=%d)\n", (int)n, (int)len);
+	if(n < 0) {
+		if(errno == EWOULDBLOCK || errno == EAGAIN || errno == EINTR) {
+			s_data_to_play = data + 2;
+			s_bytes_to_play = len;
+		} else {
+			Error("DSP_Play() write() : %s\n", strerror(errno));
+		}
+	} else if((int)n < (int)len) {
+		s_data_to_play = data + 2 + n;
+		s_bytes_to_play = len - n;
+	}
+}
+
+#define DELAY_THRESHOLD (16)
+
+uint8 DSP_GetStatus(void)
+{
+	int delay;
+	if(s_oss_fd < 0) return 0;
+	if(s_bytes_to_play > 0) return 2;
+	if(ioctl(s_oss_fd, SNDCTL_DSP_GETODELAY, &delay) < 0) {
+		Warning("ioctl SNDCTL_DSP_GETODELAY : %s\n", strerror(errno));
+		return 0;
+	}
+	if(delay < DELAY_THRESHOLD) return 0;
+	/*Debug("DSP_GetStatus() : delay=%d\n", delay);*/
+	return 2;	/* playing */
+}
+
+static void oss_tick(void)
+{
+	ssize_t n;
+	if(s_oss_fd >= 0 && s_bytes_to_play > 0) {
+		n = write(s_oss_fd, s_data_to_play, s_bytes_to_play);
+		/*Debug("  write() returned %d (len=%d)\n", (int)n, (int)s_bytes_to_play);*/
+		if(n < 0) {
+			Error("oss_tick() write() : %s\n", strerror(errno));
+		} else {
+			s_data_to_play += n;
+			s_bytes_to_play -= n;
+		}
+	}
+}