Add cross-compilation scripts for Windows

Build the Windows binary from mingw on Linux, using the official
prebuilt binaries for ffmpeg, SDL2 and adb.

MSYS2 and all its packaged dll are not necessary anymore.

Makefile.CrossWindows

@@ -0,0 +1,106 @@
+# This makefile provides recipes to build a "portable" version of scrcpy for
+# Windows.
+#
+# Here, "portable" means that the client and server binaries are expected to be
+# anywhere, but in the same directory, instead of well-defined separate
+# locations (e.g. /usr/bin/scrcpy and /usr/share/scrcpy/scrcpy-server.jar).
+#
+# In particular, this implies to change the location from where the client push
+# the server to the device.
+
+.PHONY: default clean \
+	build-server \
+	prepare-deps-win32 prepare-deps-win64 \
+	build-win32 build-win64 \
+	dist-win32 dist-win64 \
+	zip-win32 zip-win64 \
+	sums release
+
+GRADLE ?= ./gradlew
+
+SERVER_BUILD_DIR := build-server
+WIN32_BUILD_DIR := build-win32
+WIN64_BUILD_DIR := build-win64
+
+DIST := dist
+WIN32_TARGET_DIR := scrcpy-win32
+WIN64_TARGET_DIR := scrcpy-win64
+
+VERSION := $(shell git describe --tags --always)
+WIN32_TARGET := $(WIN32_TARGET_DIR)-$(VERSION).zip
+WIN64_TARGET := $(WIN64_TARGET_DIR)-$(VERSION).zip
+
+release: clean zip-win32 zip-win64 sums
+	@echo "Release created in $(DIST)/."
+
+clean:
+	$(GRADLE) clean
+	rm -rf "$(SERVER_BUILD_DIR)" "$(WIN32_BUILD_DIR)" "$(WIN64_BUILD_DIR)" "$(DIST)"
+
+build-server:
+	[ -d "$(SERVER_BUILD_DIR)" ] || ( mkdir "$(SERVER_BUILD_DIR)" && \
+		meson "$(SERVER_BUILD_DIR)" \
+			--buildtype release -Dbuild_app=false )
+		ninja -C "$(SERVER_BUILD_DIR)"
+
+prepare-deps-win32:
+	-$(MAKE) -C prebuilt-deps prepare-win32
+
+build-win32: prepare-deps-win32
+	[ -d "$(WIN32_BUILD_DIR)" ] || ( mkdir "$(WIN32_BUILD_DIR)" && \
+		meson "$(WIN32_BUILD_DIR)" \
+			--cross-file cross_win32.txt \
+			--buildtype release --strip -Db_lto=true \
+			-Dbuild_server=false \
+			-Doverride_server_path=scrcpy-server.jar )
+	ninja -C "$(WIN32_BUILD_DIR)"
+
+prepare-deps-win64:
+	-$(MAKE) -C prebuilt-deps prepare-win64
+
+build-win64: prepare-deps-win64
+	[ -d "$(WIN64_BUILD_DIR)" ] || ( mkdir "$(WIN64_BUILD_DIR)" && \
+		meson "$(WIN64_BUILD_DIR)" \
+			--cross-file cross_win64.txt \
+			--buildtype release --strip -Db_lto=true \
+			-Dbuild_server=false \
+			-Doverride_server_path=scrcpy-server.jar )
+	ninja -C "$(WIN64_BUILD_DIR)"
+
+dist-win32: build-server build-win32
+	mkdir -p "$(DIST)/$(WIN32_TARGET_DIR)"
+	cp "$(SERVER_BUILD_DIR)"/server/scrcpy-server.jar "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp "$(WIN32_BUILD_DIR)"/app/scrcpy.exe "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win32-shared/bin/avutil-56.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win32-shared/bin/avcodec-58.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win32-shared/bin/avformat-58.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win32-shared/bin/swresample-3.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/adb.exe "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/AdbWinApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/AdbWinUsbApi.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+	cp prebuilt-deps/SDL2-2.0.8/i686-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN32_TARGET_DIR)/"
+
+dist-win64: build-server build-win64
+	mkdir -p "$(DIST)/$(WIN64_TARGET_DIR)"
+	cp "$(SERVER_BUILD_DIR)"/server/scrcpy-server.jar "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp "$(WIN64_BUILD_DIR)"/app/scrcpy.exe "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win64-shared/bin/avutil-56.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win64-shared/bin/avcodec-58.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win64-shared/bin/avformat-58.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/ffmpeg-4.0-win64-shared/bin/swresample-3.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/adb.exe "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/AdbWinApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/platform-tools/AdbWinUsbApi.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+	cp prebuilt-deps/SDL2-2.0.8/x86_64-w64-mingw32/bin/SDL2.dll "$(DIST)/$(WIN64_TARGET_DIR)/"
+
+zip-win32: dist-win32
+	cd "$(DIST)"; \
+		zip -r "$(WIN32_TARGET)" "$(WIN32_TARGET_DIR)"
+
+zip-win64: dist-win64
+	cd "$(DIST)"; \
+		zip -r "$(WIN64_TARGET)" "$(WIN64_TARGET_DIR)"
+
+sums:
+	cd "$(DIST)"; \
+		sha256sum *.zip > SHA256SUM.txt

app/meson.build

@@ -19,12 +19,54 @@ src = [
     'src/tinyxpm.c',
 ]
 
-dependencies = [
-    dependency('libavformat'),
-    dependency('libavcodec'),
-    dependency('libavutil'),
-    dependency('sdl2'),
-]
+if not meson.is_cross_build()
+
+    # native build
+    dependencies = [
+        dependency('libavformat'),
+        dependency('libavcodec'),
+        dependency('libavutil'),
+        dependency('sdl2'),
+    ]
+
+else
+
+    # cross-compile mingw32 build (from Linux to Windows)
+    cc = meson.get_compiler('c')
+
+    prebuilt_sdl2 = meson.get_cross_property('prebuilt_sdl2')
+    sdl2_bin_dir = meson.current_source_dir() + '/../prebuilt-deps/' + prebuilt_sdl2 + '/bin'
+    sdl2_lib_dir = meson.current_source_dir() + '/../prebuilt-deps/' + prebuilt_sdl2 + '/lib'
+    sdl2_include_dir = '../prebuilt-deps/' + prebuilt_sdl2 + '/include'
+
+    sdl2 = declare_dependency(
+        dependencies: [
+            cc.find_library('SDL2', dirs: sdl2_bin_dir),
+            cc.find_library('SDL2main', dirs: sdl2_lib_dir),
+        ],
+        include_directories: include_directories(sdl2_include_dir)
+    )
+
+    prebuilt_ffmpeg_shared = meson.get_cross_property('prebuilt_ffmpeg_shared')
+    prebuilt_ffmpeg_dev = meson.get_cross_property('prebuilt_ffmpeg_dev')
+    ffmpeg_bin_dir = meson.current_source_dir() + '/../prebuilt-deps/' + prebuilt_ffmpeg_shared + '/bin'
+    ffmpeg_include_dir = '../prebuilt-deps/' + prebuilt_ffmpeg_dev + '/include'
+    ffmpeg = declare_dependency(
+        dependencies: [
+            cc.find_library('avcodec-58', dirs: ffmpeg_bin_dir),
+            cc.find_library('avformat-58', dirs: ffmpeg_bin_dir),
+            cc.find_library('avutil-56', dirs: ffmpeg_bin_dir),
+        ],
+        include_directories: include_directories(ffmpeg_include_dir)
+    )
+
+    dependencies = [
+        ffmpeg,
+        sdl2,
+        cc.find_library('mingw32')
+    ]
+
+endif
 
 cc = meson.get_compiler('c')
 

cross_win32.txt

@@ -0,0 +1,20 @@
+# apt install mingw-w64 mingw-w64-tools
+
+[binaries]
+name = 'mingw'
+c = '/usr/bin/i686-w64-mingw32-gcc'
+cpp = '/usr/bin/i686-w64-mingw32-g++'
+ar = '/usr/bin/i686-w64-mingw32-ar'
+strip = '/usr/bin/i686-w64-mingw32-strip'
+pkgconfig = '/usr/bin/i686-w64-mingw32-pkg-config'
+
+[host_machine]
+system = 'windows'
+cpu_family = 'x86'
+cpu = 'i686'
+endian = 'little'
+
+[properties]
+prebuilt_ffmpeg_shared = 'ffmpeg-4.0-win32-shared'
+prebuilt_ffmpeg_dev = 'ffmpeg-4.0-win32-dev'
+prebuilt_sdl2 = 'SDL2-2.0.8/i686-w64-mingw32'

cross_win64.txt

@@ -0,0 +1,20 @@
+# apt install mingw-w64 mingw-w64-tools
+
+[binaries]
+name = 'mingw'
+c = '/usr/bin/x86_64-w64-mingw32-gcc'
+cpp = '/usr/bin/x86_64-w64-mingw32-g++'
+ar = '/usr/bin/x86_64-w64-mingw32-ar'
+strip = '/usr/bin/x86_64-w64-mingw32-strip'
+pkgconfig = '/usr/bin/x86_64-w64-mingw32-pkg-config'
+
+[host_machine]
+system = 'windows'
+cpu_family = 'x86'
+cpu = 'x86_64'
+endian = 'little'
+
+[properties]
+prebuilt_ffmpeg_shared = 'ffmpeg-4.0-win64-shared'
+prebuilt_ffmpeg_dev = 'ffmpeg-4.0-win64-dev'
+prebuilt_sdl2 = 'SDL2-2.0.8/x86_64-w64-mingw32'

prebuilt-deps/.gitignore

@@ -0,0 +1,4 @@
+*
+!/.gitignore
+!/Makefile
+!/prepare-dep

prebuilt-deps/Makefile

@@ -0,0 +1,40 @@
+.PHONY: prepare-win32 prepare-win64 \
+	prepare-ffmpeg-shared-win32 \
+	prepare-ffmpeg-dev-win32 \
+	prepare-ffmpeg-shared-win64 \
+	prepare-ffmpeg-dev-win64 \
+	prepare-sdl2 \
+	prepare-adb
+
+prepare-win32: prepare-sdl2 prepare-ffmpeg-shared-win32 prepare-ffmpeg-dev-win32 prepare-adb
+prepare-win64: prepare-sdl2 prepare-ffmpeg-shared-win64 prepare-ffmpeg-dev-win64 prepare-adb
+
+prepare-ffmpeg-shared-win32:
+	@./prepare-dep https://ffmpeg.zeranoe.com/builds/win32/shared/ffmpeg-4.0-win32-shared.zip \
+		530c92df0ca14c35901b4b681847d62da3c50a0cc9b7ced37b04968f6b5c243d \
+		ffmpeg-4.0-win32-shared
+
+prepare-ffmpeg-dev-win32:
+	@./prepare-dep https://ffmpeg.zeranoe.com/builds/win32/dev/ffmpeg-4.0-win32-dev.zip \
+		e2f5200b5e73c4d0abb9b89c4ffc0438f92a0aadc54c81cf57e18c81a9f11c6b \
+		ffmpeg-4.0-win32-dev
+
+prepare-ffmpeg-shared-win64:
+	@./prepare-dep https://ffmpeg.zeranoe.com/builds/win64/shared/ffmpeg-4.0-win64-shared.zip \
+		8fe2d344463dbefc2db4239a4203a55ed0324faceaae57276a40c4fabda84c37 \
+		ffmpeg-4.0-win64-shared
+
+prepare-ffmpeg-dev-win64:
+	@./prepare-dep https://ffmpeg.zeranoe.com/builds/win64/dev/ffmpeg-4.0-win64-dev.zip \
+		facced738eabfc53fa92834dea8b24426f64db61298688fed480145945be07fa \
+		ffmpeg-4.0-win64-dev
+
+prepare-sdl2:
+	@./prepare-dep https://libsdl.org/release/SDL2-devel-2.0.8-mingw.tar.gz \
+		ffff7305d634aff5e1df5b7bb935435c3a02c8b03ad94a1a2be9169a558a7961 \
+		SDL2-2.0.8
+
+prepare-adb:
+	@./prepare-dep https://dl.google.com/android/repository/platform-tools_r27.0.1-windows.zip \
+	    880662adfb0d6911ff250b9e13930ae1a4110fc36d5866afd4f8f56d935f7939 \
+		platform-tools

prebuilt-deps/prepare-dep

@@ -0,0 +1,58 @@
+#!/bin/bash
+set -e
+url="$1"
+sum="$2"
+dir="$3"
+
+checksum() {
+    local file="$1"
+    local sum="$2"
+    echo "$file: verifying checksum..."
+    echo "$sum  $file" | sha256sum -c
+}
+
+get_file() {
+    local url="$1"
+    local file="$2"
+    local sum="$3"
+    if [[ -f "$file" ]]
+    then
+        echo "$file: found"
+    else
+        echo "$file: not found, downloading..."
+        wget "$url" -O "$file"
+    fi
+    checksum "$file" "$sum"
+}
+
+extract() {
+    local file="$1"
+    echo "Extracting $file..."
+    if [[ "$file" == *.zip ]]
+    then
+        unzip -q "$file"
+    elif [[ "$file" == *.tar.gz ]]
+    then
+        tar xf "$file"
+    else
+        echo "Unsupported file: $file"
+        return 1
+    fi
+}
+
+get_dep() {
+    local url="$1"
+    local sum="$2"
+    local dir="$3"
+    local file="${url##*/}"
+    if [[ -d "$dir" ]]
+    then
+        echo "$dir: found"
+    else
+        echo "$dir: not found"
+        get_file "$url" "$file" "$sum"
+        extract "$file"
+    fi
+}
+
+get_dep "$1" "$2" "$3"