Use libmpg123 to decode MPEG audio

mpg123 is configured as an optional dependency. Works for full files currently.

5 files changed, 137 insertions, 37 deletions

diff --git a/src/audio/player.c b/src/audio/player.c
index b2a6ae15..ef238378 100644
--- a/src/audio/player.c
+++ b/src/audio/player.c
@@ -30,6 +30,10 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
 #include <the_Foundation/thread.h>
 #include <SDL_audio.h>
 
+#if defined (LAGRANGE_ENABLE_MPG123)
+#  include <mpg123.h>
+#endif
+
 /*----------------------------------------------------------------------------------------------*/
 
 iDeclareType(ContentSpec)
@@ -68,6 +72,9 @@ struct Impl_Decoder {
     uint64_t          currentSample;
     uint64_t          totalSamples; /* zero if unknown */
     stb_vorbis *      vorbis;
+#if defined (LAGRANGE_ENABLE_MPG123)
+    mpg123_handle *   mpeg;
+#endif
 };
 
 enum iDecoderStatus {
@@ -155,8 +162,18 @@ static enum iDecoderStatus decodeWav_Decoder_(iDecoder *d, iRanges inputRange) {
     return ok_DecoderStatus;
 }
 
-static enum iDecoderStatus decodeVorbis_Decoder_(iDecoder *d, iRanges inputRange) {
-    iUnused(inputRange);
+static void writePending_Decoder_(iDecoder *d) {
+    /* Write as much as we can. */
+    lock_Mutex(&d->outputMutex);
+    size_t avail = vacancy_SampleBuf(&d->output);
+    size_t n = iMin(avail, size_Array(&d->pendingOutput));
+    write_SampleBuf(&d->output, constData_Array(&d->pendingOutput), n);
+    removeN_Array(&d->pendingOutput, 0, n);
+    unlock_Mutex(&d->outputMutex);
+    d->currentSample += n;
+}
+
+static enum iDecoderStatus decodeVorbis_Decoder_(iDecoder *d) {
     const iBlock *input = &d->input->data;
     if (!d->vorbis) {
         lock_Mutex(&d->input->mtx);
@@ -213,14 +230,47 @@ static enum iDecoderStatus decodeVorbis_Decoder_(iDecoder *d, iRanges inputRange
             }
         }
     }
-    /* Write as much as we can. */
-    lock_Mutex(&d->outputMutex);
-    size_t avail = vacancy_SampleBuf(&d->output);
-    size_t n = iMin(avail, size_Array(&d->pendingOutput));
-    write_SampleBuf(&d->output, constData_Array(&d->pendingOutput), n);
-    removeN_Array(&d->pendingOutput, 0, n);
-    unlock_Mutex(&d->outputMutex);
-    d->currentSample += n;
+    writePending_Decoder_(d);
+    return status;
+}
+
+enum iDecoderStatus decodeMpeg_Decoder_(iDecoder *d) {
+    enum iDecoderStatus status = ok_DecoderStatus;
+#if defined (LAGRANGE_ENABLE_MPG123)
+    const iBlock *input = &d->input->data;
+    if (!d->mpeg) {
+        d->mpeg = mpg123_new(NULL, NULL);
+        mpg123_format_none(d->mpeg);
+        mpg123_format(d->mpeg, d->outputFreq, d->output.numChannels, MPG123_ENC_SIGNED_16);
+        mpg123_open_feed(d->mpeg);
+        lock_Mutex(&d->input->mtx);
+        mpg123_feed(d->mpeg, constData_Block(input), size_Block(input));
+        unlock_Mutex(&d->input->mtx);
+        long r; int ch, enc;
+        mpg123_getformat(d->mpeg, &r, &ch, &enc);
+        iAssert(r == d->outputFreq);
+        iAssert(ch == d->output.numChannels);
+        iAssert(enc == MPG123_ENC_SIGNED_16);
+    }
+    while (size_Array(&d->pendingOutput) < d->output.count) {
+        int16_t buffer[512];
+        size_t bytesWritten = 0;
+        const int rc = mpg123_read(d->mpeg, buffer, sizeof(buffer), &bytesWritten);
+        const float gain = d->gain;
+        for (size_t i = 0; i < bytesWritten / 2; i++) {
+            buffer[i] *= gain;
+        }
+        pushBackN_Array(&d->pendingOutput, buffer, bytesWritten / 2 / d->output.numChannels);
+        if (rc == MPG123_NEED_MORE) {
+            status = needMoreInput_DecoderStatus;
+            break;
+        }
+        else if (rc == MPG123_DONE) {
+            break;
+        }
+    }
+    writePending_Decoder_(d);
+#endif
     return status;
 }
 
@@ -242,7 +292,11 @@ static iThreadResult run_Decoder_(iThread *thread) {
                     status = decodeWav_Decoder_(d, inputRange);
                     break;
                 case vorbis_DecoderType:
-                    status = decodeVorbis_Decoder_(d, inputRange);
+                    status = decodeVorbis_Decoder_(d);
+                    break;
+                case mpeg_DecoderType:
+                    status = decodeMpeg_Decoder_(d);
+                    break;
                 default:
                     break;
             }
@@ -280,6 +334,9 @@ void init_Decoder(iDecoder *d, iInputBuf *input, const iContentSpec *spec) {
     d->currentSample = 0;
     d->totalSamples  = spec->totalSamples;
     d->vorbis = NULL;
+#if defined (LAGRANGE_ENABLE_MPG123)
+    d->mpeg = NULL;
+#endif
     init_Mutex(&d->outputMutex);
     d->thread = new_Thread(run_Decoder_);
     setUserData_Thread(d->thread, d);
@@ -295,6 +352,15 @@ void deinit_Decoder(iDecoder *d) {
     deinit_Mutex(&d->outputMutex);
     deinit_SampleBuf(&d->output);
     deinit_Array(&d->pendingOutput);
+    if (d->vorbis) {
+        stb_vorbis_close(d->vorbis);
+    }
+#if defined (LAGRANGE_ENABLE_MPG123)
+    if (d->mpeg) {
+        mpg123_close(d->mpeg);
+        mpg123_delete(d->mpeg);
+    }
+#endif
 }
 
 iDefineTypeConstructionArgs(Decoder, (iInputBuf *input, const iContentSpec *spec),
@@ -336,6 +402,11 @@ static iContentSpec contentSpec_Player_(const iPlayer *d) {
              !cmp_String(&d->mime, "audio/x-vorbis+ogg")) {
         content.type = vorbis_DecoderType;
     }
+#if defined (LAGRANGE_ENABLE_MPG123)
+    else if (!cmp_String(&d->mime, "audio/mpeg") || !cmp_String(&d->mime, "audio/mp3")) {
+        content.type = mpeg_DecoderType;
+    }
+#endif
     else {
         /* TODO: Could try decoders to see if one works? */
         content.type = none_DecoderType;
@@ -438,6 +509,24 @@ static iContentSpec contentSpec_Player_(const iPlayer *d) {
         content.inputFormat     = AUDIO_F32; /* actually stb_vorbis provides floats */
         stb_vorbis_close(vrb);
     }
+    else if (content.type == mpeg_DecoderType) {
+#if defined (LAGRANGE_ENABLE_MPG123)
+        mpg123_handle *mh = mpg123_new(NULL, NULL);
+        mpg123_open_feed(mh);
+        mpg123_feed(mh, constData_Block(&d->data->data), size_Block(&d->data->data));
+        long rate = 0;
+        int channels = 0;
+        int encoding = 0;
+        if (mpg123_getformat(mh, &rate, &channels, &encoding) == MPG123_OK) {
+            content.output.freq     = rate;
+            content.output.channels = channels;
+            content.inputFormat     = AUDIO_S16;
+            content.output.format   = AUDIO_S16;
+        }
+        mpg123_close(mh);
+        mpg123_delete(mh);
+#endif
+    }
     iAssert(content.inputFormat == content.output.format ||
             (content.inputFormat == AUDIO_S24LSB && content.output.format == AUDIO_S16) ||
             (content.inputFormat == AUDIO_F64LSB && content.output.format == AUDIO_F32));
diff --git a/src/gmrequest.c b/src/gmrequest.c
index dd2c2720..7b6414d2 100644
--- a/src/gmrequest.c
+++ b/src/gmrequest.c
@@ -460,6 +460,9 @@ void submit_GmRequest(iGmRequest *d) {
             else if (endsWithCase_String(path, ".ogg")) {
                 setCStr_String(&d->resp.meta, "audio/ogg");
             }
+            else if (endsWithCase_String(path, ".mp3")) {
+                setCStr_String(&d->resp.meta, "audio/mpeg");
+            }
             else {
                 setCStr_String(&d->resp.meta, "application/octet-stream");
             }
diff --git a/src/macos.h b/src/macos.h
index 700d50f8..ee06b69e 100644
--- a/src/macos.h
+++ b/src/macos.h
@@ -28,6 +28,8 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
 
 iBool   shouldDefaultToMetalRenderer_MacOS  (void);
 
-void    setupApplication_MacOS  (void);
-void    insertMenuItems_MacOS   (const char *menuLabel, int atIndex, const iMenuItem *items, size_t count);
-void    handleCommand_MacOS     (const char *cmd);
+void    enableMomentumScroll_MacOS  (void);
+void    registerURLHandler_MacOS    (void);
+void    setupApplication_MacOS      (void);
+void    insertMenuItems_MacOS       (const char *menuLabel, int atIndex, const iMenuItem *items, size_t count);
+void    handleCommand_MacOS         (const char *cmd);
diff --git a/src/main.c b/src/main.c
index 464176e6..de9132ab 100644
--- a/src/main.c
+++ b/src/main.c
@@ -20,25 +20,25 @@ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
 
-#include <the_Foundation/commandline.h>
-#include <stdio.h>
-#if defined (iPlatformMsys)
-#  define SDL_MAIN_HANDLED
-#endif
-#include <SDL.h>
-
 #include "app.h"
 
 #if defined (iPlatformApple)
-extern void enableMomentumScroll_MacOS(void);
-extern void registerURLHandler_MacOS(void);
+#  include "macos.h"
 #endif
-
 #if defined (iPlatformMsys)
 #  include "win32.h"
+#  define SDL_MAIN_HANDLED
 #endif
+#if defined (LAGRANGE_ENABLE_MPG123)
+#  include <mpg123.h>
+#endif
+
+#include <the_Foundation/commandline.h>
+#include <SDL.h>
+#include <stdio.h>
 
 int main(int argc, char **argv) {
+    printf("Lagrange: A Beautiful Gemini Client\n");
 #if defined (iPlatformApple)
     enableMomentumScroll_MacOS();
     registerURLHandler_MacOS();
@@ -48,9 +48,11 @@ int main(int argc, char **argv) {
     setDPIAware_Win32();
     SDL_SetMainReady();
 #endif
+    /* Initialize libraries. */
+#if defined (LAGRANGE_ENABLE_MPG123)
+    mpg123_init();
+#endif
     init_Foundation();
-    printf("Lagrange: A Beautiful Gemini Client\n");
-    /* Initialize SDL. */
     SDL_SetHint(SDL_HINT_VIDEO_ALLOW_SCREENSAVER, "1");
     if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) {
         fprintf(stderr, "SDL init failed: %s\n", SDL_GetError());
@@ -58,5 +60,8 @@ int main(int argc, char **argv) {
     }
     run_App(argc, argv);
     SDL_Quit();
+#if defined (LAGRANGE_ENABLE_MPG123)
+    mpg123_exit();
+#endif
     return 0;
 }
diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index 5adb8bd0..b540a999 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -1584,17 +1584,18 @@ static iBool processAudioPlayerEvents_DocumentWidget_(iDocumentWidget *d, const
         if (contains_Rect(rect, mouse)) {
             iPlayerUI ui;
             init_PlayerUI(&ui, plr, rect);
-            if (ev->type == SDL_MOUSEBUTTONDOWN || ev->type == SDL_MOUSEMOTION) {
-                if (ev->type == SDL_MOUSEBUTTONDOWN &&
-                    flags_Player(plr) & adjustingVolume_PlayerFlag &&
-                    contains_Rect(adjusted_Rect(ui.volumeAdjustRect,
-                                                zero_I2(),
-                                                init_I2(-height_Rect(ui.volumeAdjustRect), 0)),
-                                  mouse)) {
-                    setGrabbedPlayer_DocumentWidget_(d, run);
-                    processEvent_Click(&d->click, ev);
-                    /* The rest is done in the DocumentWidget click responder. */
-                }
+            if (ev->type == SDL_MOUSEBUTTONDOWN && flags_Player(plr) & adjustingVolume_PlayerFlag &&
+                contains_Rect(adjusted_Rect(ui.volumeAdjustRect,
+                                            zero_I2(),
+                                            init_I2(-height_Rect(ui.volumeAdjustRect), 0)),
+                              mouse)) {
+                setGrabbedPlayer_DocumentWidget_(d, run);
+                processEvent_Click(&d->click, ev);
+                /* The rest is done in the DocumentWidget click responder. */
+                refresh_Widget(d);
+                return iTrue;
+            }
+            else if (ev->type == SDL_MOUSEBUTTONDOWN || ev->type == SDL_MOUSEMOTION) {
                 refresh_Widget(d);
                 return iTrue;
             }