fix(main/python-torchaudio): enable ffmpeg support by creating a torc…

…haudio-ffmpeg subpackage

based on code from the audacity-ffmpeg subpackage
https://github.com/termux/termux-packages/tree/fd2e21fcffc72c0f5192bf296cf31a89f448eb39/x11-packages/audacity

packages/python-torchaudio/build.sh

@@ -3,18 +3,82 @@ TERMUX_PKG_DESCRIPTION="Data manipulation and transformation for audio signal pr
 TERMUX_PKG_LICENSE="BSD 2-Clause"
 TERMUX_PKG_MAINTAINER="@termux"
 TERMUX_PKG_VERSION=2.5.0
-TERMUX_PKG_SRCURL=git+https://github.com/pytorch/audio
-# FFMPEG
-TERMUX_PKG_DEPENDS="libc++, python, python-pip, python-torch"
+TERMUX_PKG_REVISION=1
+# FFmpeg 7 is not yet supported. The subpackage should be removed when FFmpeg 7
+# is supported by an upstream release.
+# https://github.com/pytorch/audio/issues/3857
+_FFMPEG_VERSION=6.1.2
+_FFMPEG_SRCURL="https://www.ffmpeg.org/releases/ffmpeg-$_FFMPEG_VERSION.tar.xz"
+_FFMPEG_RM_AFTER_INSTALL="
+opt/torchaudio/include
+opt/torchaudio/lib/pkgconfig
+opt/torchaudio/share
+"
+TERMUX_PKG_SRCURL=(https://github.com/pytorch/audio/archive/refs/tags/v${TERMUX_PKG_VERSION}.tar.gz
+                   $_FFMPEG_SRCURL)
+TERMUX_PKG_SHA256=(fca49590d36966879f37cef29dcc83507e97e7cad68035a851734d93066c018e
+                   3b624649725ecdc565c903ca6643d41f33bd49239922e45c9b1442c63dca4e38)
+TERMUX_PKG_DEPENDS="libc++, python, python-pip, python-torch, torchaudio-ffmpeg"
 TERMUX_PKG_PYTHON_COMMON_DEPS="wheel, setuptools"
+TERMUX_PKG_RM_AFTER_INSTALL=$_FFMPEG_RM_AFTER_INSTALL
+
+_ffmpeg_configure_make_install() {
+	export _FFMPEG_PREFIX=${TERMUX_PREFIX}/opt/torchaudio
+	LDFLAGS="-Wl,-rpath=${_FFMPEG_PREFIX}/lib ${LDFLAGS}"
+
+	local _ARCH
+	case ${TERMUX_ARCH} in
+		arm ) _ARCH=armeabi-v7a ;;
+		i686 ) _ARCH=x86 ;;
+		* ) _ARCH=$TERMUX_ARCH ;;
+	esac
+
+	mkdir -p _ffmpeg-${_FFMPEG_VERSION}
+	pushd _ffmpeg-${_FFMPEG_VERSION}
+	$TERMUX_PKG_SRCDIR/ffmpeg-${_FFMPEG_VERSION}/configure \
+		--prefix=${_FFMPEG_PREFIX} \
+		--cc=${CC} \
+		--pkg-config=false \
+		--arch=${_ARCH} \
+		--cross-prefix=llvm- \
+		--enable-cross-compile \
+		--target-os=android \
+		--disable-version3 \
+		--disable-static \
+		--enable-shared \
+		--disable-all \
+		--disable-autodetect \
+		--disable-doc \
+		--enable-avcodec \
+		--enable-avformat \
+		--enable-avdevice \
+		--enable-avfilter \
+		--disable-asm
+	make -j ${TERMUX_PKG_MAKE_PROCESSES}
+	make install
+	popd
+}
+
+_ffmpeg_post_make_install() {
+	local _FFMPEG_DOCDIR=$TERMUX_PREFIX/share/doc/torchaudio-ffmpeg
+	mkdir -p ${_FFMPEG_DOCDIR}
+	ln -sfr ${TERMUX_PREFIX}/share/LICENSES/LGPL-2.1.txt \
+		${_FFMPEG_DOCDIR}/LICENSE
+}
+
+_ffmpeg_post_massage() {
+	rm -rf lib/pkgconfig
+}
 
 termux_step_pre_configure() {
+	_ffmpeg_configure_make_install
 	termux_setup_cmake
 	termux_setup_ninja
 
 	export BUILD_VERSION=$TERMUX_PKG_VERSION
-	# FIXME: The same as torchvision, upstream doesn't support ffmpeg 6.
-	export USE_FFMPEG=0
+	export FFMPEG_ROOT="$_FFMPEG_PREFIX"
+	# use this FFMPEG_ROOT when the system ffmpeg package can work
+	# export FFMPEG_ROOT="$TERMUX_PREFIX"
 	export TORCHAUDIO_CMAKE_PREFIX_PATH="$TERMUX_PYTHON_HOME/site-packages/torch;$TERMUX_PREFIX"
 	export host_alias="$TERMUX_HOST_PLATFORM"
 }
@@ -26,3 +90,11 @@ termux_step_configure() {
 termux_step_make_install() {
 	pip -v install --no-build-isolation --no-deps --prefix "$TERMUX_PREFIX" "$TERMUX_PKG_SRCDIR"
 }
+
+termux_step_post_make_install() {
+	_ffmpeg_post_make_install
+}
+
+termux_step_post_massage() {
+	_ffmpeg_post_massage
+}

packages/python-torchaudio/ffmpeg-configure.patch

@@ -0,0 +1,51 @@
++++ ./ffmpeg-6.1.2/configure
+@@ -5336,13 +5336,9 @@
+         striptype=""
+         ;;
+     android)
+-        disable symver
+         enable section_data_rel_ro
+         add_cflags -fPIE
+         add_ldexeflags -fPIE -pie
+-        SLIB_INSTALL_NAME='$(SLIBNAME)'
+-        SLIB_INSTALL_LINKS=
+-        SHFLAGS='-shared -Wl,-soname,$(SLIBNAME)'
+         ;;
+     haiku)
+         prefix_default="/boot/common"
++++ ./ffmpeg-6.1.2/libavcodec/allcodecs.c
+@@ -154,7 +154,6 @@
+ extern const FFCodec ff_h264_crystalhd_decoder;
+ extern const FFCodec ff_h264_v4l2m2m_decoder;
+ extern const FFCodec ff_h264_mediacodec_decoder;
+-extern const FFCodec ff_h264_mediacodec_encoder;
+ extern const FFCodec ff_h264_mmal_decoder;
+ extern const FFCodec ff_h264_qsv_decoder;
+ extern const FFCodec ff_h264_rkmpp_decoder;
+@@ -850,6 +849,7 @@
+ extern const FFCodec ff_libopenh264_decoder;
+ extern const FFCodec ff_h264_amf_encoder;
+ extern const FFCodec ff_h264_cuvid_decoder;
++extern const FFCodec ff_h264_mediacodec_encoder;
+ extern const FFCodec ff_h264_mf_encoder;
+ extern const FFCodec ff_h264_nvenc_encoder;
+ extern const FFCodec ff_h264_omx_encoder;
++++ ./ffmpeg-6.1.2/libavutil/file_open.c
+@@ -119,7 +119,7 @@
+ #undef free
+     free(ptr);
+ #else
+-    size_t len = strlen(prefix) + 12; /* room for "/tmp/" and "XXXXXX\0" */
++    size_t len = strlen(prefix) + strlen("@TERMUX_PREFIX@/tmp/") + 7; /* room for "@TERMUX_PREFIX@/tmp/" and "XXXXXX\0" */
+     *filename  = av_malloc(len);
+ #endif
+     /* -----common section-----*/
+@@ -136,7 +136,7 @@
+ #   endif
+     fd = open(*filename, O_RDWR | O_BINARY | O_CREAT | O_EXCL, 0600);
+ #else
+-    snprintf(*filename, len, "/tmp/%sXXXXXX", prefix);
++    snprintf(*filename, len, "@TERMUX_PREFIX@/tmp/%sXXXXXX", prefix);
+     fd = mkstemp(*filename);
+ #if defined(_WIN32) || defined (__ANDROID__)
+     if (fd < 0) {

packages/python-torchaudio/torchaudio-ffmpeg.subpackage.sh

@@ -0,0 +1,6 @@
+
+TERMUX_SUBPKG_DESCRIPTION="Minimal FFmpeg libraries for python-torchaudio"
+TERMUX_SUBPKG_INCLUDE="
+opt/torchaudio/lib/
+share/doc/torchaudio-ffmpeg/
+"