1 files changed, 137 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/ay.c b/lib/rbcodec/codecs/ay.c
new file mode 100644
index 0000000000..b11ad84294
--- /dev/null
+++ b/lib/rbcodec/codecs/ay.c
@@ -0,0 +1,137 @@
+
+/* Ripped off from Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ */
+
+#include <codecs/lib/codeclib.h>
+#include "libgme/ay_emu.h" 
+
+CODEC_HEADER
+
+/* Maximum number of bytes to process in one iteration */
+#define CHUNK_SIZE (1024*2)
+
+static int16_t samples[CHUNK_SIZE] IBSS_ATTR;
+static struct Ay_Emu ay_emu;
+
+/****************** rockbox interface ******************/
+
+static void set_codec_track(int t, int multitrack) {
+    Ay_start_track(&ay_emu, t); 
+
+    /* for loop mode we disable track limits */
+    if (!ci->loop_track()) {
+        Track_set_fade(&ay_emu, Track_get_length( &ay_emu, t ) - 4000, 4000);
+    }
+    if (multitrack) ci->set_elapsed(t*1000); /* t is track no to display */
+    else ci->set_elapsed(0);
+}
+
+/* this is the codec entry point */
+enum codec_status codec_main(enum codec_entry_call_reason reason)
+{
+    if (reason == CODEC_LOAD) {
+        /* we only render 16 bits */
+        ci->configure(DSP_SET_SAMPLE_DEPTH, 16);
+
+        /* 44 Khz, Interleaved stereo */
+        ci->configure(DSP_SET_FREQUENCY, 44100);
+        ci->configure(DSP_SET_STEREO_MODE, STEREO_INTERLEAVED);
+
+        Ay_init(&ay_emu);
+        Ay_set_sample_rate(&ay_emu, 44100);
+    }
+
+    return CODEC_OK;
+}
+
+/* this is called for each file to process */
+enum codec_status codec_run(void)
+{
+    blargg_err_t err;
+    uint8_t *buf;
+    size_t n;
+    int track, is_multitrack;
+    intptr_t param;
+    uint32_t elapsed_time;
+
+    /* reset values */
+    track = is_multitrack = 0;
+    elapsed_time = 0;
+
+    DEBUGF("AY: next_track\n");
+    if (codec_init()) {
+        return CODEC_ERROR;
+    }  
+
+    codec_set_replaygain(ci->id3);
+        
+    /* Read the entire file */
+    DEBUGF("AY: request file\n");
+    ci->seek_buffer(0);
+    buf = ci->request_buffer(&n, ci->filesize);
+    if (!buf || n < (size_t)ci->filesize) {
+        DEBUGF("AY: file load failed\n");
+        return CODEC_ERROR;
+    }
+   
+    if ((err = Ay_load_mem(&ay_emu, buf, ci->filesize))) {
+        DEBUGF("AY: Ay_load_mem failed (%s)\n", err);
+        return CODEC_ERROR;
+    }
+
+    /* Update internal track count */
+    if (ay_emu.m3u.size > 0)
+        ay_emu.track_count = ay_emu.m3u.size;
+
+    /* Check if file has multiple tracks */
+    if (ay_emu.track_count > 1) {
+        is_multitrack = 1;
+    }
+
+next_track:
+    set_codec_track(track, is_multitrack);
+
+    /* The main decoder loop */
+    while (1) {
+        enum codec_command_action action = ci->get_command(&param);
+
+        if (action == CODEC_ACTION_HALT)
+            break;
+
+        if (action == CODEC_ACTION_SEEK_TIME) {
+            if (is_multitrack) {
+                track = param/1000;
+                ci->seek_complete();
+                if (track >= ay_emu.track_count) break;
+                goto next_track;
+            }
+
+            ci->set_elapsed(param);
+            elapsed_time = param;
+            Track_seek(&ay_emu, param);
+            ci->seek_complete();
+            
+            /* Set fade again */
+            if (!ci->loop_track()) {
+                Track_set_fade(&ay_emu, Track_get_length( &ay_emu, track ) - 4000, 4000);
+            }
+        }
+
+        /* Generate audio buffer */
+        err = Ay_play(&ay_emu, CHUNK_SIZE, samples);
+        if (err || Track_ended(&ay_emu)) {
+            track++;
+            if (track >= ay_emu.track_count) break;
+            goto next_track;
+        }
+
+        ci->pcmbuf_insert(samples, NULL, CHUNK_SIZE >> 1);
+
+        /* Set elapsed time for one track files */
+        if (!is_multitrack) {
+            elapsed_time += (CHUNK_SIZE / 2) * 10 / 441;
+            ci->set_elapsed(elapsed_time);
+        }
+    }
+
+    return CODEC_OK;
+}