1 files changed, 278 insertions, 0 deletions

diff --git a/Alc/midi/base.c b/Alc/midi/base.c
new file mode 100644
index 00000000..25dd19d9
--- /dev/null
+++ b/Alc/midi/base.c
@@ -0,0 +1,278 @@
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+#include "midi/base.h"
+
+#include "alMidi.h"
+#include "alMain.h"
+#include "alError.h"
+#include "alThunk.h"
+#include "evtqueue.h"
+#include "rwlock.h"
+#include "alu.h"
+
+
+/* Microsecond resolution */
+#define TICKS_PER_SECOND (1000000)
+
+/* MIDI events */
+#define SYSEX_EVENT  (0xF0)
+
+
+void InitEvtQueue(EvtQueue *queue)
+{
+    queue->events = NULL;
+    queue->maxsize = 0;
+    queue->size = 0;
+    queue->pos = 0;
+}
+
+void ResetEvtQueue(EvtQueue *queue)
+{
+    ALsizei i;
+    for(i = 0;i < queue->size;i++)
+    {
+        if(queue->events[i].event == SYSEX_EVENT)
+        {
+            free(queue->events[i].param.sysex.data);
+            queue->events[i].param.sysex.data = NULL;
+        }
+    }
+
+    free(queue->events);
+    queue->events = NULL;
+    queue->maxsize = 0;
+    queue->size = 0;
+    queue->pos = 0;
+}
+
+ALenum InsertEvtQueue(EvtQueue *queue, const MidiEvent *evt)
+{
+    ALsizei pos;
+
+    if(queue->maxsize == queue->size)
+    {
+        if(queue->pos > 0)
+        {
+            /* Queue has some stale entries, remove them to make space for more
+             * events. */
+            for(pos = 0;pos < queue->pos;pos++)
+            {
+                if(queue->events[pos].event == SYSEX_EVENT)
+                {
+                    free(queue->events[pos].param.sysex.data);
+                    queue->events[pos].param.sysex.data = NULL;
+                }
+            }
+            memmove(&queue->events[0], &queue->events[queue->pos],
+                    (queue->size-queue->pos)*sizeof(queue->events[0]));
+            queue->size -= queue->pos;
+            queue->pos = 0;
+        }
+        else
+        {
+            /* Queue is full, double the allocated space. */
+            void *temp = NULL;
+            ALsizei newsize;
+
+            newsize = (queue->maxsize ? (queue->maxsize<<1) : 16);
+            if(newsize > queue->maxsize)
+                temp = realloc(queue->events, newsize * sizeof(queue->events[0]));
+            if(!temp)
+                return AL_OUT_OF_MEMORY;
+
+            queue->events = temp;
+            queue->maxsize = newsize;
+        }
+    }
+
+    pos = queue->pos;
+    if(queue->size > 0)
+    {
+        ALsizei high = queue->size - 1;
+        while(pos < high)
+        {
+            ALsizei mid = pos + (high-pos)/2;
+            if(queue->events[mid].time < evt->time)
+                pos = mid + 1;
+            else
+                high = mid;
+        }
+        while(pos < queue->size && queue->events[pos].time <= evt->time)
+            pos++;
+
+        if(pos < queue->size)
+            memmove(&queue->events[pos+1], &queue->events[pos],
+                    (queue->size-pos)*sizeof(queue->events[0]));
+    }
+
+    queue->events[pos] = *evt;
+    queue->size++;
+
+    return AL_NO_ERROR;
+}
+
+
+void MidiSynth_Construct(MidiSynth *self, ALCdevice *device)
+{
+    InitEvtQueue(&self->EventQueue);
+
+    RWLockInit(&self->Lock);
+
+    self->Soundfonts = NULL;
+    self->NumSoundfonts = 0;
+
+    self->Gain = 1.0f;
+    self->State = AL_INITIAL;
+
+    self->LastEvtTime = 0;
+    self->NextEvtTime = UINT64_MAX;
+    self->SamplesSinceLast = 0.0;
+    self->SamplesToNext = 0.0;
+
+    self->SamplesPerTick = (ALdouble)device->Frequency / TICKS_PER_SECOND;
+}
+
+void MidiSynth_Destruct(MidiSynth *self)
+{
+    ALsizei i;
+
+    for(i = 0;i < self->NumSoundfonts;i++)
+        DecrementRef(&self->Soundfonts[i]->ref);
+    free(self->Soundfonts);
+    self->Soundfonts = NULL;
+    self->NumSoundfonts = 0;
+
+    ResetEvtQueue(&self->EventQueue);
+}
+
+
+ALenum MidiSynth_selectSoundfonts(MidiSynth *self, ALCcontext *context, ALsizei count, const ALuint *ids)
+{
+    ALCdevice *device = context->Device;
+    ALsoundfont **sfonts;
+    ALsizei i;
+
+    if(self->State != AL_INITIAL && self->State != AL_STOPPED)
+        return AL_INVALID_OPERATION;
+
+    sfonts = calloc(1, count * sizeof(sfonts[0]));
+    if(!sfonts) return AL_OUT_OF_MEMORY;
+
+    for(i = 0;i < count;i++)
+    {
+        if(ids[i] == 0)
+            sfonts[i] = ALsoundfont_getDefSoundfont(context);
+        else if(!(sfonts[i]=LookupSfont(device, ids[i])))
+        {
+            free(sfonts);
+            return AL_INVALID_VALUE;
+        }
+    }
+
+    for(i = 0;i < count;i++)
+        IncrementRef(&sfonts[i]->ref);
+    sfonts = ExchangePtr((XchgPtr*)&self->Soundfonts, sfonts);
+    count = ExchangeInt(&self->NumSoundfonts, count);
+
+    for(i = 0;i < count;i++)
+        DecrementRef(&sfonts[i]->ref);
+    free(sfonts);
+
+    return AL_NO_ERROR;
+}
+
+extern inline void MidiSynth_setGain(MidiSynth *self, ALfloat gain);
+extern inline ALfloat MidiSynth_getGain(const MidiSynth *self);
+extern inline void MidiSynth_setState(MidiSynth *self, ALenum state);
+extern inline ALenum MidiSynth_getState(const MidiSynth *self);
+
+void MidiSynth_stop(MidiSynth *self)
+{
+    ResetEvtQueue(&self->EventQueue);
+
+    self->LastEvtTime = 0;
+    self->NextEvtTime = UINT64_MAX;
+    self->SamplesSinceLast = 0.0;
+    self->SamplesToNext = 0.0;
+}
+
+extern inline void MidiSynth_reset(MidiSynth *self);
+
+ALuint64 MidiSynth_getTime(const MidiSynth *self)
+{
+    ALuint64 time = self->LastEvtTime + (self->SamplesSinceLast/self->SamplesPerTick);
+    return clampu64(time, self->LastEvtTime, self->NextEvtTime);
+}
+
+extern inline ALuint64 MidiSynth_getNextEvtTime(const MidiSynth *self);
+
+void MidiSynth_setSampleRate(MidiSynth *self, ALdouble srate)
+{
+    ALdouble sampletickrate = srate / TICKS_PER_SECOND;
+
+    self->SamplesSinceLast = self->SamplesSinceLast * sampletickrate / self->SamplesPerTick;
+    self->SamplesToNext = self->SamplesToNext * sampletickrate / self->SamplesPerTick;
+    self->SamplesPerTick = sampletickrate;
+}
+
+extern inline void MidiSynth_update(MidiSynth *self, ALCdevice *device);
+
+ALenum MidiSynth_insertEvent(MidiSynth *self, ALuint64 time, ALuint event, ALsizei param1, ALsizei param2)
+{
+    MidiEvent entry;
+    ALenum err;
+
+    entry.time = time;
+    entry.event = event;
+    entry.param.val[0] = param1;
+    entry.param.val[1] = param2;
+
+    err = InsertEvtQueue(&self->EventQueue, &entry);
+    if(err != AL_NO_ERROR) return err;
+
+    if(entry.time < self->NextEvtTime)
+    {
+        self->NextEvtTime = entry.time;
+
+        self->SamplesToNext  = (self->NextEvtTime - self->LastEvtTime) * self->SamplesPerTick;
+        self->SamplesToNext -= self->SamplesSinceLast;
+    }
+
+    return AL_NO_ERROR;
+}
+
+ALenum MidiSynth_insertSysExEvent(MidiSynth *self, ALuint64 time, const ALbyte *data, ALsizei size)
+{
+    MidiEvent entry;
+    ALenum err;
+
+    entry.time = time;
+    entry.event = SYSEX_EVENT;
+    entry.param.sysex.size = size;
+    entry.param.sysex.data = malloc(size);
+    if(!entry.param.sysex.data)
+        return AL_OUT_OF_MEMORY;
+    memcpy(entry.param.sysex.data, data, size);
+
+    err = InsertEvtQueue(&self->EventQueue, &entry);
+    if(err != AL_NO_ERROR)
+    {
+        free(entry.param.sysex.data);
+        return err;
+    }
+
+    if(entry.time < self->NextEvtTime)
+    {
+        self->NextEvtTime = entry.time;
+
+        self->SamplesToNext  = (self->NextEvtTime - self->LastEvtTime) * self->SamplesPerTick;
+        self->SamplesToNext -= self->SamplesSinceLast;
+    }
+
+    return AL_NO_ERROR;
+}