introduce MDESound

sound/CMakeLists.txt

@@ -0,0 +1,6 @@
+setup_lib(sound Sound)
+target_link_libraries(
+	MDESound
+	PRIVATE
+	MDECore
+)

sound/id3.c

@@ -0,0 +1,102 @@
+#include <MDE/Sound/ID3.h>
+#include <MDE/Core/String.h>
+
+static unsigned int syncsafe(FILE* f) {
+        unsigned char d[4];
+        unsigned int  r = 0;
+        int           i;
+        fread(d, 4, 1, f);
+
+        for(i = 0; i < 4; i++) {
+                r = r << 7;
+                r = r | (d[i] & 127);
+        }
+
+        return r;
+}
+
+static unsigned int big(FILE* f) {
+        unsigned char d[4];
+        unsigned int  r = 0;
+        int           i;
+        fread(d, 4, 1, f);
+
+        for(i = 0; i < 4; i++) {
+                r = r << 8;
+                r = r | d[i];
+        }
+
+        return r;
+}
+
+char* MDEID3GetTag(const char* path, const char* name, size_t* size){
+        FILE*          f = fopen(path, "rb");
+        unsigned char* d = NULL;
+        char           sig[3];
+        unsigned char  ver[2];
+        unsigned char  flag;
+        unsigned char  frame[4];
+        unsigned int   dsz = 0;
+        if(f == NULL) return NULL;
+
+        fread(sig, 3, 1, f);
+        if(memcmp(sig, "ID3", 3) != 0) return NULL;
+
+        fread(ver, 2, 1, f);
+        if(memcmp(ver, "\x04\x00", 2) != 0 && memcmp(ver, "\x03\x00", 2) != 0) return NULL;
+
+        fread(&flag, 1, 1, f);
+        if(flag & (1 << 6)) return NULL; /* FIXME */
+        if(flag & (1 << 7)) return NULL; /* what even is this??? */
+
+        dsz = syncsafe(f);
+
+        while(dsz > 0) {
+                unsigned int fsz;
+
+                fread(frame, 4, 1, f);
+                if(frame[0] == 0) break; /* XXX: Is this ok? */
+
+                if(memcmp(ver, "\x04\x00", 2) == 0) {
+                        fsz = syncsafe(f);
+                } else {
+                        fsz = big(f);
+                }
+
+                fseek(f, 2, SEEK_CUR);
+                if(memcmp(frame, name, strlen(name)) == 0) {
+			d = malloc(fsz);
+			fread(d, fsz, 1, f);
+
+			*size = fsz;
+			break;
+                } else {
+                        fseek(f, fsz, SEEK_CUR);
+                }
+
+                dsz -= 4 + 4 + 2 + fsz;
+        }
+
+        fclose(f);
+
+        return d;
+}
+
+char* MDEID3GetString(const char* path, const char* name){
+	size_t sz;
+	unsigned char* d = MDEID3GetTag(path, name, &sz);
+	char* s;
+	if(d == NULL) return NULL;
+	if(d[0] == 1 || d[0] == 2){
+		free(d);
+		return NULL;
+	}
+
+	s = malloc(sz - 1 + 1);
+	memcpy(s, d + 1, sz - 1);
+	s[sz - 1] = 0;
+
+	free(d);
+
+	return s;
+}

sound/mp3.c

@@ -0,0 +1,54 @@
+#include <MDE/Sound/Sound.h>
+#include <MDE/Sound/ID3.h>
+
+#define DR_MP3_IMPLEMENTATION
+#include <dr_mp3.h>
+
+static MDESoundContext mp3_open(const char* path){
+	MDESoundContext ctx = malloc(sizeof(*ctx));
+	memset(ctx, 0, sizeof(*ctx));
+
+	ctx->title = MDEID3GetString(path, "TIT2");
+	ctx->artist = MDEID3GetString(path, "TPE1");
+	ctx->album = MDEID3GetString(path, "TALB");
+	ctx->genre = MDEID3GetString(path, "TCON");
+
+	ctx->opaque = malloc(sizeof(drmp3));
+	if(!drmp3_init_file(ctx->opaque, path, NULL)){
+		free(ctx);
+		return NULL;
+	}
+
+	ctx->channels = ((drmp3*)ctx->opaque)->channels;
+	ctx->sample_rate = ((drmp3*)ctx->opaque)->sampleRate;
+	ctx->frames = drmp3_get_pcm_frame_count(ctx->opaque);
+
+	return ctx;
+}
+
+static void mp3_close(MDESoundContext ctx){
+	if(ctx->title != NULL) free(ctx->title);
+	if(ctx->artist != NULL) free(ctx->artist);
+	if(ctx->album != NULL) free(ctx->album);
+	if(ctx->genre != NULL) free(ctx->genre);
+
+	drmp3_uninit(ctx->opaque);
+	free(ctx->opaque);
+	free(ctx);
+}
+
+static int mp3_read(MDESoundContext ctx, short* out, int frames){
+	return drmp3_read_pcm_frames_s16(ctx->opaque, frames, out);
+}
+
+static void mp3_seek(MDESoundContext ctx, int frames){
+	drmp3_seek_to_pcm_frame(ctx->opaque, frames);
+}
+
+static MDESoundDriverRec rec = {
+	mp3_open,
+	mp3_close,
+	mp3_read,
+	mp3_seek
+};
+MDESoundDriver MDESoundDriverMP3 = &rec;

sound/sound.c

@@ -0,0 +1,69 @@
+#include <MDE/Sound/Sound.h>
+
+#define TRY_DRIVER(name) \
+	if(sound->context == NULL){ \
+		sound->driver = MDESoundDriver ## name; \
+		sound->context = MDESoundDriver ## name->open(path); \
+	}
+
+MDESound MDESoundOpen(const char* path){
+	MDESound sound = malloc(sizeof(*sound));
+	sound->context = NULL;
+
+	TRY_DRIVER(MP3);
+
+	if(sound->context == NULL){
+		free(sound);
+		return NULL;
+	}
+
+	if(sound->context->channels != 2 && sound->context->channels != 1){
+		MDESoundClose(sound);
+		return NULL;
+	}
+
+	return sound;
+}
+
+int MDESoundRead(MDESound sound, short* out, int frames){
+	short* f = malloc(sizeof(*f) * sound->context->channels * frames);
+	int r = sound->driver->read(sound->context, f, frames);
+	int i;
+	if(sound->context->channels == 2){
+		for(i = 0; i < r * 2; i++){
+			out[i] = f[i];
+		}
+	}else if(sound->context->channels == 1){
+		for(i = 0; i < r; i++){
+			out[i * 2 + 0] = f[i];
+			out[i * 2 + 1] = f[i];
+		}
+		r *= 2;
+	}
+	free(f);
+
+	return r;
+}
+
+int MDESoundReadFloat(MDESound sound, float* out, int frames){
+	short* f = malloc(sizeof(*f) * 2 * frames);
+	int i;
+	int r = MDESoundRead(sound, f, frames);
+
+	for(i = 0; i < r * 2; i++){
+		out[i] = f[i] / 32767.0;
+	}
+
+	free(f);
+
+	return r;
+}
+
+void MDESoundSeek(MDESound sound, int frames){
+	sound->driver->seek(sound->context, frames);
+}
+
+void MDESoundClose(MDESound sound){
+	sound->driver->close(sound->context);
+	free(sound);
+}