[FFmpeg-devel] [PATCH 1/2] lavc/mediacodec_wrapper: factorize MediaCodec creation functions

Matthieu Bouron matthieu.bouron at gmail.com
Thu Dec 14 19:06:11 EET 2017


On Thu, Dec 14, 2017 at 01:02:49PM +0100, wm4 wrote:
> On Thu, 14 Dec 2017 12:53:38 +0100
> Matthieu Bouron <matthieu.bouron at gmail.com> wrote:
> 
> > On Thu, Dec 14, 2017 at 12:21:28PM +0100, wm4 wrote:
> > > On Thu, 14 Dec 2017 11:09:13 +0100
> > > Matthieu Bouron <matthieu.bouron at gmail.com> wrote:
> > >   
> > > > ---
> > > >  libavcodec/mediacodec_wrapper.c | 262 +++++++++++-----------------------------
> > > >  1 file changed, 70 insertions(+), 192 deletions(-)
> > > > 
> > > > diff --git a/libavcodec/mediacodec_wrapper.c b/libavcodec/mediacodec_wrapper.c
> > > > index f34450a6d8..4660e895ca 100644
> > > > --- a/libavcodec/mediacodec_wrapper.c
> > > > +++ b/libavcodec/mediacodec_wrapper.c
> > > > @@ -1132,200 +1132,78 @@ fail:  
> > > 
> > >   
> > > > +#define DECLARE_FF_AMEDIACODEC_CREATE_FUNC(func, jfunc)                                     \
> > > > +FFAMediaCodec* ff_AMediaCodec_##func(const char *arg)                                       \
> > > > +{                                                                                           \
> > > > +    int ret = -1;                                                                           \
> > > > +    JNIEnv *env = NULL;                                                                     \
> > > > +    FFAMediaCodec *codec = NULL;                                                            \
> > > > +    jstring jarg = NULL;                                                                    \
> > > > +    jobject object = NULL;                                                                  \
> > > > +                                                                                            \
> > > > +    codec = av_mallocz(sizeof(FFAMediaCodec));                                              \
> > > > +    if (!codec) {                                                                           \
> > > > +        return NULL;                                                                        \
> > > > +    }                                                                                       \
> > > > +    codec->class = &amediacodec_class;                                                      \
> > > > +                                                                                            \
> > > > +    env = ff_jni_get_env(codec);                                                            \
> > > > +    if (!env) {                                                                             \
> > > > +        av_freep(&codec);                                                                   \
> > > > +        return NULL;                                                                        \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    if (ff_jni_init_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec) < 0) { \
> > > > +        goto fail;                                                                          \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    jarg = ff_jni_utf_chars_to_jstring(env, arg, codec);                                    \
> > > > +    if (!jarg) {                                                                            \
> > > > +        goto fail;                                                                          \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    object = (*env)->CallStaticObjectMethod(env,                                            \
> > > > +                                            codec->jfields.mediacodec_class,                \
> > > > +                                            codec->jfields.jfunc,                           \
> > > > +                                            jarg);                                          \
> > > > +    if (ff_jni_exception_check(env, 1, codec) < 0) {                                        \
> > > > +        goto fail;                                                                          \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    codec->object = (*env)->NewGlobalRef(env, object);                                      \
> > > > +    if (!codec->object) {                                                                   \
> > > > +        goto fail;                                                                          \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    if (codec_init_static_fields(codec) < 0) {                                              \
> > > > +        goto fail;                                                                          \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    if (codec->jfields.get_input_buffer_id && codec->jfields.get_output_buffer_id) {        \
> > > > +        codec->has_get_i_o_buffer = 1;                                                      \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    ret = 0;                                                                                \
> > > > +fail:                                                                                       \
> > > > +    if (jarg) {                                                                             \
> > > > +        (*env)->DeleteLocalRef(env, jarg);                                                  \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    if (object) {                                                                           \
> > > > +        (*env)->DeleteLocalRef(env, object);                                                \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    if (ret < 0) {                                                                          \
> > > > +        ff_jni_reset_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec);      \
> > > > +        av_freep(&codec);                                                                   \
> > > > +    }                                                                                       \
> > > > +                                                                                            \
> > > > +    return codec;                                                                           \
> > > >  }
> > > >    
> > > 
> > > Such long macros are very ugly. And the only macro argument that is
> > > used in the body is jfunc. Would it be possible to move most of the
> > > macro into a proper function, with jfunc as pointer argument or so?  
> > 
> > I agree with you that such macros are ugly.
> > 
> > I used this approach as the jfunc value cannot be known before
> > ff_jni_init_jfields is called.
> > 
> > I will try another approach and send a new patch.
> 
> Right, it seems it's not as simple as passing a pointer. Maybe
> offsetof() could help.

Patch updated. I did not use offsetof as it felt a bit weird to pass an
offset of a struct to a function to call the right method.

-- 
Matthieu B.
-------------- next part --------------
>From 250e87f2834a4780c3056837dadc511dac7af25e Mon Sep 17 00:00:00 2001
From: Matthieu Bouron <matthieu.bouron at gmail.com>
Date: Wed, 13 Dec 2017 13:49:58 +0100
Subject: [PATCH] lavc/mediacodec_wrapper: factorize MediaCodec creation
 functions

---
 libavcodec/mediacodec_wrapper.c | 162 +++++++---------------------------------
 1 file changed, 29 insertions(+), 133 deletions(-)

diff --git a/libavcodec/mediacodec_wrapper.c b/libavcodec/mediacodec_wrapper.c
index f34450a6d8..329a5eb896 100644
--- a/libavcodec/mediacodec_wrapper.c
+++ b/libavcodec/mediacodec_wrapper.c
@@ -1132,13 +1132,18 @@ fail:
     return ret;
 }
 
-FFAMediaCodec* ff_AMediaCodec_createCodecByName(const char *name)
+#define CREATE_CODEC_BY_NAME   0
+#define CREATE_DECODER_BY_TYPE 1
+#define CREATE_ENCODER_BY_TYPE 2
+
+static inline FFAMediaCodec *codec_create(int method, const char *arg)
 {
     int ret = -1;
     JNIEnv *env = NULL;
     FFAMediaCodec *codec = NULL;
-    jstring codec_name = NULL;
+    jstring jarg = NULL;
     jobject object = NULL;
+    jmethodID create_id = NULL;
 
     codec = av_mallocz(sizeof(FFAMediaCodec));
     if (!codec) {
@@ -1156,77 +1161,23 @@ FFAMediaCodec* ff_AMediaCodec_createCodecByName(const char *name)
         goto fail;
     }
 
-    codec_name = ff_jni_utf_chars_to_jstring(env, name, codec);
-    if (!codec_name) {
-        goto fail;
-    }
-
-    object = (*env)->CallStaticObjectMethod(env, codec->jfields.mediacodec_class, codec->jfields.create_by_codec_name_id, codec_name);
-    if (ff_jni_exception_check(env, 1, codec) < 0) {
-        goto fail;
-    }
-
-    codec->object = (*env)->NewGlobalRef(env, object);
-    if (!codec->object) {
-        goto fail;
-    }
-
-    if (codec_init_static_fields(codec) < 0) {
-        goto fail;
-    }
-
-    if (codec->jfields.get_input_buffer_id && codec->jfields.get_output_buffer_id) {
-        codec->has_get_i_o_buffer = 1;
-    }
-
-    ret = 0;
-fail:
-    if (codec_name) {
-        (*env)->DeleteLocalRef(env, codec_name);
-    }
-
-    if (object) {
-        (*env)->DeleteLocalRef(env, object);
-    }
-
-    if (ret < 0) {
-        ff_jni_reset_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec);
-        av_freep(&codec);
-    }
-
-    return codec;
-}
-
-FFAMediaCodec* ff_AMediaCodec_createDecoderByType(const char *mime)
-{
-    int ret = -1;
-    JNIEnv *env = NULL;
-    FFAMediaCodec *codec = NULL;
-    jstring mime_type = NULL;
-    jobject object = NULL;
-
-    codec = av_mallocz(sizeof(FFAMediaCodec));
-    if (!codec) {
-        return NULL;
-    }
-    codec->class = &amediacodec_class;
-
-    env = ff_jni_get_env(codec);
-    if (!env) {
-        av_freep(&codec);
-        return NULL;
-    }
-
-    if (ff_jni_init_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec) < 0) {
+    jarg = ff_jni_utf_chars_to_jstring(env, arg, codec);
+    if (!jarg) {
         goto fail;
     }
 
-    mime_type = ff_jni_utf_chars_to_jstring(env, mime, codec);
-    if (!mime_type) {
-        goto fail;
+    switch (method) {
+    case CREATE_CODEC_BY_NAME:   create_id = codec->jfields.create_by_codec_name_id;   break;
+    case CREATE_DECODER_BY_TYPE: create_id = codec->jfields.create_decoder_by_type_id; break;
+    case CREATE_ENCODER_BY_TYPE: create_id = codec->jfields.create_encoder_by_type_id; break;
+    default:
+        av_assert0(0);
     }
 
-    object = (*env)->CallStaticObjectMethod(env, codec->jfields.mediacodec_class, codec->jfields.create_decoder_by_type_id, mime_type);
+    object = (*env)->CallStaticObjectMethod(env,
+                                            codec->jfields.mediacodec_class,
+                                            create_id,
+                                            jarg);
     if (ff_jni_exception_check(env, 1, codec) < 0) {
         goto fail;
     }
@@ -1246,8 +1197,8 @@ FFAMediaCodec* ff_AMediaCodec_createDecoderByType(const char *mime)
 
     ret = 0;
 fail:
-    if (mime_type) {
-        (*env)->DeleteLocalRef(env, mime_type);
+    if (jarg) {
+        (*env)->DeleteLocalRef(env, jarg);
     }
 
     if (object) {
@@ -1262,70 +1213,15 @@ fail:
     return codec;
 }
 
-FFAMediaCodec* ff_AMediaCodec_createEncoderByType(const char *mime)
-{
-    int ret = -1;
-    JNIEnv *env = NULL;
-    FFAMediaCodec *codec = NULL;
-    jstring mime_type = NULL;
-    jobject object = NULL;
+#define DECLARE_FF_AMEDIACODEC_CREATE_FUNC(name, method) \
+FFAMediaCodec *ff_AMediaCodec_##name(const char *arg)    \
+{                                                        \
+    return codec_create(method, arg);                    \
+}                                                        \
 
-    codec = av_mallocz(sizeof(FFAMediaCodec));
-    if (!codec) {
-        return NULL;
-    }
-    codec->class = &amediacodec_class;
-
-    env = ff_jni_get_env(codec);
-    if (!env) {
-        av_freep(&codec);
-        return NULL;
-    }
-
-    if (ff_jni_init_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec) < 0) {
-        goto fail;
-    }
-
-    mime_type = ff_jni_utf_chars_to_jstring(env, mime, codec);
-    if (!mime_type) {
-        goto fail;
-    }
-
-    object = (*env)->CallStaticObjectMethod(env, codec->jfields.mediacodec_class, codec->jfields.create_encoder_by_type_id, mime_type);
-    if (ff_jni_exception_check(env, 1, codec) < 0) {
-        goto fail;
-    }
-
-    codec->object = (*env)->NewGlobalRef(env, object);
-    if (!codec->object) {
-        goto fail;
-    }
-
-    if (codec_init_static_fields(codec) < 0) {
-        goto fail;
-    }
-
-    if (codec->jfields.get_input_buffer_id && codec->jfields.get_output_buffer_id) {
-        codec->has_get_i_o_buffer = 1;
-    }
-
-    ret = 0;
-fail:
-    if (mime_type) {
-        (*env)->DeleteLocalRef(env, mime_type);
-    }
-
-    if (object) {
-        (*env)->DeleteLocalRef(env, object);
-    }
-
-    if  (ret < 0) {
-        ff_jni_reset_jfields(env, &codec->jfields, jni_amediacodec_mapping, 1, codec);
-        av_freep(&codec);
-    }
-
-    return codec;
-}
+DECLARE_FF_AMEDIACODEC_CREATE_FUNC(createCodecByName,   CREATE_CODEC_BY_NAME)
+DECLARE_FF_AMEDIACODEC_CREATE_FUNC(createDecoderByType, CREATE_DECODER_BY_TYPE)
+DECLARE_FF_AMEDIACODEC_CREATE_FUNC(createEncoderByType, CREATE_ENCODER_BY_TYPE)
 
 int ff_AMediaCodec_delete(FFAMediaCodec* codec)
 {
-- 
2.15.1



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