Add codecs to librbcodec.

Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>

lib/rbcodec/codecs/hes.c

@@ -0,0 +1,108 @@
+/* Ripped off from Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ */
+
+#include <string.h>
+#include "codeclib.h"
+#include "libgme/hes_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 Hes_Emu hes_emu;
+
+/****************** rockbox interface ******************/
+
+static void set_codec_track(int t) {
+    Hes_start_track(&hes_emu, t); 
+
+    /* for loop mode we disable track limits */
+    if (!ci->loop_track()) {
+        Track_set_fade(&hes_emu, Track_get_length( &hes_emu, t ), 4000);
+    }
+    ci->set_elapsed(t*1000); /* t is track no to display */
+}
+
+/* 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);
+
+        Hes_init(&hes_emu);
+        Hes_set_sample_rate(&hes_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;
+    intptr_t param;
+    int track = 0;
+    
+    DEBUGF("HES: next_track\n");
+    if (codec_init()) {
+        return CODEC_ERROR;
+    }  
+
+    codec_set_replaygain(ci->id3);
+
+    /* Read the entire file */
+    DEBUGF("HES: request file\n");
+    ci->seek_buffer(0);
+    buf = ci->request_buffer(&n, ci->filesize);
+    if (!buf || n < (size_t)ci->filesize) {
+        DEBUGF("HES: file load failed\n");
+        return CODEC_ERROR;
+    }
+
+    if ((err = Hes_load_mem(&hes_emu, buf, ci->filesize))) {
+        DEBUGF("HES: Hes_load_mem failed (%s)\n", err);
+        return CODEC_ERROR;
+    }
+
+    /* Update internal track count */
+    if (hes_emu.m3u.size > 0)
+        hes_emu.track_count = hes_emu.m3u.size;
+
+next_track:
+    set_codec_track(track);
+
+    /* 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) {
+            track = param/1000;
+            ci->seek_complete();
+            if (track >= hes_emu.track_count) break;
+            goto next_track;
+        }
+
+        /* Generate audio buffer */
+        err = Hes_play(&hes_emu, CHUNK_SIZE, samples);
+        if (err || Track_ended(&hes_emu)) {
+            track++;
+            if (track >= hes_emu.track_count) break;
+            goto next_track;
+        }
+
+        ci->pcmbuf_insert(samples, NULL, CHUNK_SIZE >> 1);
+    }
+
+    return CODEC_OK;
+}