BASIC audio keywords; documentation coming soon

Author: braindigitalis

include/audio.h

@@ -189,6 +189,14 @@ audio_device_t *mixer_device(void);
  */
 void mixer_idle(void);
 
+void mixer_stop_stream(mixer_stream_t* ch);
+
+void mixer_pause_stream(mixer_stream_t* ch);
+
+void mixer_resume_stream(mixer_stream_t* ch);
+
+bool mixer_stream_is_paused(mixer_stream_t* ch);
+
 /**
  * @brief Convert a memory-resident WAV into 44.1 kHz stereo S16_LE
  *
@@ -253,3 +261,4 @@ size_t wav_size_to_samples(size_t length);
  * @return         Size in bytes of the decoded buffer
  */
 size_t wav_samples_to_size(size_t samples);
+

include/basic/audio.h

@@ -0,0 +1,19 @@
+#pragma once
+#include <kernel.h>
+#include <audio.h>
+
+int64_t assign_stream(struct basic_ctx* ctx);
+
+bool release_stream(struct basic_ctx* ctx, int64_t stream_id);
+
+mixer_stream_t* get_stream(struct basic_ctx* ctx, int64_t stream_id);
+
+void stream_statement(struct basic_ctx* ctx);
+
+void sound_statement(struct basic_ctx* ctx);
+
+int64_t basic_decibels(struct basic_ctx* ctx);
+
+void sound_list_free_all(struct basic_ctx *ctx);
+
+void stream_list_free_all(struct basic_ctx *ctx);

include/basic/context.h

@@ -7,6 +7,7 @@
 #include <stdbool.h>
 #include "tokenizer.h"
 #include "buddy_allocator.h"
+#include "audio.h"
 
 typedef struct {
 	uint16_t source_port;
@@ -17,6 +18,12 @@ typedef struct {
 	struct queued_udp_packet* next;
 } queued_udp_packet;
 
+typedef struct basic_sound_t {
+	int16_t *pcm;			/* interleaved S16LE */
+	size_t frames;			/* stereo frames */
+	struct basic_sound_t* next;	/* Next */
+} basic_sound_t;
+
 /**
  * @brief BASIC program context.
  *
@@ -331,6 +338,11 @@ typedef struct basic_ctx {
 	buddy_allocator_t* allocator;
 
 	queued_udp_packet last_packet;
+
+	mixer_stream_t* audio_streams[64];
+
+	basic_sound_t* sounds;
+
 } basic_ctx;
 
 /**

include/basic/tokenizer.h

@@ -188,8 +188,19 @@ typedef void (*keyword_handler_t)(struct basic_ctx*);
     T(SOCKBINREAD, STMT, sockbinread_statement)		/* 116 */ \
     T(BINREAD, STMT, readbinary_statement) 		/* 117 */ \
     T(BINWRITE, STMT, writebinary_statement) 		/* 118 */ \
-    T(GRAPHPRINT, STMT, graphprint_statement) 		/* 118 */ \
-    T(VDU, STMT, vdu_statement) 			/* 118 */ \
+    T(GRAPHPRINT, STMT, graphprint_statement) 		/* 119 */ \
+    T(VDU, STMT, vdu_statement) 			/* 120 */ \
+    T(STREAM, STMT, stream_statement) 			/* 121 */ \
+    T(CREATE, STMT, NULL) 				/* 122 */ \
+    T(DESTROY, STMT, NULL) 				/* 123 */ \
+    T(SOUND, STMT, sound_statement) 			/* 124 */ \
+    T(VOLUME, STMT, NULL) 				/* 125 */ \
+    T(PLAY, STMT, NULL) 				/* 126 */ \
+    T(STOP, STMT, NULL) 				/* 127 */ \
+    T(PAUSE, STMT, NULL) 				/* 128 */ \
+    T(LOAD, STMT, NULL) 				/* 129 */ \
+    T(UNLOAD, STMT, NULL) 				/* 130 */ \
+
 
 GENERATE_ENUM_LIST(TOKEN, token_t)
 

src/audio/mixer.c

@@ -26,6 +26,7 @@ struct mixer_stream {
 	uint32_t queued_frames;   /* total frames queued across chunks */
 	uint16_t gain_q8_8;       /* 256 == 1.0 */
 	bool muted;
+	bool paused;
 	bool in_use;
 	uint32_t chunk_frames;    /* preferred chunk allocation size (frames) */
 };
@@ -43,6 +44,7 @@ typedef struct {
 
 	/* Idle registration state */
 	bool idle_registered;
+
 } mixer_state_t;
 
 static mixer_state_t mix;
@@ -168,6 +170,7 @@ mixer_stream_t *mixer_create_stream(void) {
 			ch->queued_frames = 0;
 			ch->gain_q8_8 = 256u;   /* 1.0 */
 			ch->muted = false;
+			ch->paused = false;
 			ch->in_use = true;
 			ch->chunk_frames = 2048u; /* ~42.7 ms @ 48 kHz */
 			return ch;
@@ -177,11 +180,30 @@ mixer_stream_t *mixer_create_stream(void) {
 	return NULL;
 }
 
-void mixer_free_stream(mixer_stream_t *ch) {
+void mixer_pause_stream(mixer_stream_t *ch) {
 	if (!ch) {
 		return;
 	}
 
+	ch->paused = true;
+}
+
+void mixer_resume_stream(mixer_stream_t *ch) {
+	if (!ch) {
+		return;
+	}
+
+	ch->paused = false;
+}
+
+bool mixer_stream_is_paused(mixer_stream_t* ch) {
+	if (!ch) {
+		return false;
+	}
+	return ch->paused;
+}
+
+void mixer_stop_stream(mixer_stream_t* ch) {
 	/* Drop any queued audio */
 	chunk_t *p = ch->head;
 	while (p) {
@@ -193,6 +215,14 @@ void mixer_free_stream(mixer_stream_t *ch) {
 	ch->head = NULL;
 	ch->tail = NULL;
 	ch->queued_frames = 0;
+}
+
+void mixer_free_stream(mixer_stream_t *ch) {
+	if (!ch) {
+		return;
+	}
+
+	mixer_stop_stream(ch);
 	ch->in_use = false;
 }
 
@@ -293,7 +323,7 @@ void mixer_idle(void)
 		/* mix stream into this block */
 		for (uint32_t c = 0; c < mix.streams_cap; c++) {
 			struct mixer_stream *ch = &mix.streams[c];
-			if (!ch->in_use || ch->muted || !ch->head) {
+			if (!ch->in_use || ch->muted || !ch->head || ch->paused) {
 				continue;
 			}