Add darwin arm64 libs (#368)

Add opus and openh264 for arm64

Co-authored-by: Atsushi Watanabe <atsushi.w@ieee.org>
Co-authored-by: Earther <qn.khuat@gmail.com>

Makefile

@@ -16,7 +16,8 @@ supported_platforms := \
   linux-arm64 \
   linux-x64 \
   windows-x64 \
-  darwin-x64
+  darwin-x64 \
+  darwin-arm64
 cmd_build := build
 cmd_test := test
 examples_dir := examples

dockerfiles/darwin-arm64.Dockerfile

@@ -0,0 +1,47 @@
+FROM dockercore/golang-cross as m1cross
+
+ARG DEBIAN_FRONTEND=noninteractive
+RUN apt-get update -qq && apt-get install -y -q --no-install-recommends \
+    cmake \
+    git \
+    libssl-dev \
+    libxml2-dev \
+    libz-dev \
+  && rm -rf /var/lib/apt/lists/*
+
+ENV SDK_VERSION=11.3 \
+    TARGET_DIR=/osxcross/target \
+    UNATTENDED=1
+
+WORKDIR /work
+RUN git clone --depth=1 https://github.com/tpoechtrager/osxcross.git /work \
+  && cd /work/tarballs \
+  && wget -q https://github.com/phracker/MacOSX-SDKs/releases/download/${SDK_VERSION}/MacOSX${SDK_VERSION}.sdk.tar.xz
+
+# Build cross compile toolchain for Apple silicon
+RUN ./build.sh
+
+
+FROM dockcross/base
+
+ENV OSX_CROSS_PATH=/osxcross
+
+COPY --from=m1cross "${OSX_CROSS_PATH}/." "${OSX_CROSS_PATH}/"
+ENV PATH=${OSX_CROSS_PATH}/target/bin:$PATH
+
+COPY init.sh /tmp/init.sh
+RUN bash /tmp/init.sh
+
+ENV CC=arm64-apple-darwin20.4-clang \
+    CXX=arm64-apple-darwin20.4-clang++ \
+    CPP=arm64-apple-darwin20.4-clang++ \
+    AR=arm64-apple-darwin20.4-ar \
+    AS=arm64-apple-darwin20.4-as \
+    LD=arm64-apple-darwin20.4-ld
+
+COPY darwin-arm64.cmake ${OSX_CROSS_PATH}/
+ENV CMAKE_TOOLCHAIN_FILE ${OSX_CROSS_PATH}/darwin-arm64.cmake
+
+ARG IMAGE=lherman/cross-darwin-arm64
+ARG VERSION=latest
+ENV DEFAULT_DOCKCROSS_IMAGE ${IMAGE}:${VERSION}

dockerfiles/darwin-arm64.cmake

@@ -0,0 +1,8 @@
+set(CMAKE_SYSTEM_NAME Darwin)
+set(CMAKE_SYSTEM_VERSION 1)
+set(CMAKE_SYSTEM_PROCESSOR arm64)
+
+set(CMAKE_C_COMPILER $ENV{CC})
+set(CMAKE_CXX_COMPILER $ENV{CXX})
+set(CMAKE_AR $ENV{AR})
+set(CMAKE_ASM_COMPILER ${CMAKE_C_COMPILER})

pkg/codec/opus/opus_static.go

@@ -8,5 +8,6 @@ package opus
 //#cgo linux,arm64 LDFLAGS: ${SRCDIR}/lib/libopus-linux-arm64.a -lm
 //#cgo linux,amd64 LDFLAGS: ${SRCDIR}/lib/libopus-linux-x64.a -lm
 //#cgo darwin,amd64 LDFLAGS: ${SRCDIR}/lib/libopus-darwin-x64.a
+//#cgo darwin,arm64 LDFLAGS: ${SRCDIR}/lib/libopus-darwin-arm64.a
 //#cgo windows,amd64 LDFLAGS: ${SRCDIR}/lib/libopus-windows-x64.a
 import "C"