Add Android CI

This adds to the CI a cross build for Android NDK r16 API 21 (because
thats what GStreamer currently use) for arm64.

GNU iconv must be built manually into our docker image because Android
NDK doesn't seems to ship it. The latest NDK r17 API 28 has iconv.h but
iconv_open() symbol isn't found by the linker. Looks like broken NDK.

libffi also needs to be built manually because the meson subproject
doesn't support building for Android platform. It needs a recent RC
release because latest stable release is 4 years old and fails to
build.

Fixes #1385.

.gitlab-ci.yml

@@ -1,4 +1,4 @@
-image: registry.gitlab.gnome.org/gnome/glib/master:v1
+image: registry.gitlab.gnome.org/gnome/glib/master:v2
 
 stages:
   - build
@@ -32,6 +32,18 @@ fedora-meson-x86_64:
       - "${CI_PROJECT_DIR}/_build/meson-logs"
       - "${CI_PROJECT_DIR}/_coverage"
 
+fedora-meson-android_ndk_r16_api21_arm64:
+  stage: build
+  except:
+    - tags
+  script:
+    # FIXME: add --werror
+    - meson --cross-file=/opt/cross-file-android_ndk_r16_api21_arm64.txt -Diconv=gnu -Dinternal_pcre=true --buildtype debug _build
+    - ninja -C _build
+  artifacts:
+    paths:
+      - "${CI_PROJECT_DIR}/_build/meson-logs"
+
 msys2-mingw32:
   stage: build
   tags:

.gitlab-ci/Dockerfile

@@ -25,10 +25,16 @@ RUN dnf -y install \
     python3-wheel \
     systemtap-sdt-devel \
     zlib-devel \
+    wget \
+    unzip \
+    make \
  && dnf clean all
 
 RUN pip3 install meson
 
+COPY setup-android-ndk.sh .
+RUN ./setup-android-ndk.sh
+
 ARG HOST_USER_ID=5555
 ENV HOST_USER_ID ${HOST_USER_ID}
 RUN useradd -u $HOST_USER_ID -ms /bin/bash user

.gitlab-ci/setup-android-ndk.sh

@@ -0,0 +1,106 @@
+#!/bin/bash
+
+#
+# Copyright 2018 Collabora ltd.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, see <http://www.gnu.org/licenses/>.
+#
+# Author: Xavier Claessens <xavier.claessens@collabora.com>
+#
+
+set -e
+
+cd /opt
+
+# Download Android NDK
+wget --quiet https://dl.google.com/android/repository/android-ndk-r16-linux-x86_64.zip
+echo "5b9ec70eac78f6cef8572dff9a133c9b18c83155dc6d980237a6925df4ae65b7b2adb3d8ea55b3ce9f3f75868f20eefdb8c87da110683c2dd1a1a27c44dc5b91  android-ndk-r16-linux-x86_64.zip" | sha512sum -c
+unzip android-ndk-r16-linux-x86_64.zip
+rm android-ndk-r16-linux-x86_64.zip
+
+# Setup cross build env
+export ANDROID_HOST=aarch64-linux-android
+export ANDROID_BUILD=linux-x86_64
+export ANDROID_ARCH=arm64
+export ANDROID_NDK=/opt/android-ndk-r16
+export ANDROID_VERSION=21
+export ANDROID_TOOLCHAIN_VERSION=4.9
+export ANDROID_SYSROOT=$ANDROID_NDK/platforms/android-$ANDROID_VERSION/arch-$ANDROID_ARCH
+export ANDROID_PREBUILT=$ANDROID_NDK/toolchains/$ANDROID_HOST-$ANDROID_TOOLCHAIN_VERSION/prebuilt/$ANDROID_BUILD/bin
+export CPPFLAGS="--sysroot=$ANDROID_SYSROOT -isystem $ANDROID_NDK/sysroot/usr/include/  -isystem $ANDROID_NDK/sysroot/usr/include/$ANDROID_HOST"
+export CFLAGS="$CPPFLAGS -D__ANDROID_API__=$ANDROID_VERSION"
+export AR=$ANDROID_HOST-ar
+export RANLIB=$ANDROID_HOST-ranlib
+export CPP=$ANDROID_HOST-cpp
+export PATH=$ANDROID_PREBUILT:$PATH
+
+# Cross build libiconv
+wget --quiet http://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.15.tar.gz
+echo "1233fe3ca09341b53354fd4bfe342a7589181145a1232c9919583a8c9979636855839049f3406f253a9d9829908816bb71fd6d34dd544ba290d6f04251376b1a  libiconv-1.15.tar.gz" | sha512sum -c
+tar xzf libiconv-1.15.tar.gz
+rm libiconv-1.15.tar.gz
+pushd libiconv-1.15
+./configure --host=$ANDROID_HOST --prefix=/opt/$ANDROID_HOST  --libdir=/opt/$ANDROID_HOST/lib64
+make
+make install
+popd
+
+# Cross build libffi
+wget --quiet https://github.com/libffi/libffi/releases/download/v3.3-rc0/libffi-3.3-rc0.tar.gz
+echo "e6e695d32cd6eb7d65983f32986fccdfc786a593d2ea18af30ce741f58cfa1eb264b1a8d09df5084cb916001aea15187b005c2149a0620a44397a4453b6137d4  libffi-3.3-rc0.tar.gz" | sha512sum -c
+tar xzf libffi-3.3-rc0.tar.gz
+rm libffi-3.3-rc0.tar.gz
+pushd libffi-3.3-rc0
+./configure --host=$ANDROID_HOST --prefix=/opt/$ANDROID_HOST --libdir=/opt/$ANDROID_HOST/lib64
+make
+make install
+popd
+
+# Create a pkg-config wrapper that won't pick fedora libraries
+export PKG_CONFIG=/opt/${ANDROID_HOST}/bin/pkg-config
+cat > $PKG_CONFIG <<- EOM
+#!/bin/sh
+SYSROOT=/opt/${ANDROID_HOST}
+export PKG_CONFIG_DIR=
+export PKG_CONFIG_LIBDIR=\${SYSROOT}/lib64/pkgconfig
+export PKG_CONFIG_SYSROOT_DIR=\${SYSROOT}
+exec pkg-config "\$@"
+EOM
+chmod +x $PKG_CONFIG
+
+# Create a cross file that can be passed to meson
+cat > /opt/cross-file-android_ndk_r16_api21_arm64.txt <<- EOM
+[host_machine]
+system = 'android'
+cpu_family = 'arm64'
+cpu = 'arm64'
+endian = 'little'
+
+[properties]
+c_args = ['--sysroot=${ANDROID_SYSROOT}',
+          '-isystem', '/opt/${ANDROID_HOST}/include',
+          '-isystem', '${ANDROID_NDK}/sysroot/usr/include/',
+          '-isystem', '${ANDROID_NDK}/sysroot/usr/include/${ANDROID_HOST}',
+          '-D__ANDROID_API__=${ANDROID_VERSION}']
+c_link_args = ['--sysroot=${ANDROID_SYSROOT}',
+               '-L/opt/${ANDROID_HOST}/lib64',
+               '-fuse-ld=gold']
+
+[binaries]
+c = '${ANDROID_PREBUILT}/${ANDROID_HOST}-gcc'
+cpp = '${ANDROID_PREBUILT}/${ANDROID_HOST}-g++'
+ar = '${ANDROID_PREBUILT}/${ANDROID_HOST}-ar'
+strip = '${ANDROID_PREBUILT}/${ANDROID_HOST}-strip'
+pkgconfig = '${PKG_CONFIG}'
+EOM