Add Docker-based build process

.gitignore

@@ -0,0 +1,3 @@
+bazel-*
+out/
+WORKSPACE

CONTRIBUTING.md

@@ -25,4 +25,4 @@ information on using pull requests.
 ## Community Guidelines
 
 This project follows
-[Google's Open Source Community Guidelines](https://opensource.google/conduct/).
+[Google's Open Source Community Guidelines](https://opensource.google/conduct/).

Makefile

@@ -18,8 +18,10 @@ OS := $(shell uname -s)
 
 ifeq ($(OS),Linux)
 CPU ?= k8
+WORKSPACE_PLATFORM_FILE := WORKSPACE.linux
 else ifeq ($(OS),Darwin)
 CPU ?= darwin
+WORKSPACE_PLATFORM_FILE := WORKSPACE.darwin
 else
 $(error $(OS) is not supported)
 endif
@@ -37,12 +39,9 @@ BAZEL_OUT_DIR := $(MAKEFILE_DIR)/bazel-out/$(CPU)-$(COMPILATION_MODE)/bin
 
 # Linux-specific parameters
 BAZEL_BUILD_TARGET_Linux := //tflite/public:libedgetpu_direct_all.so
-# --experimental_repo_remote_exec for remotable parameter used in
-# --`repository_rule` from TF.
 BAZEL_BUILD_FLAGS_Linux := --crosstool_top=@crosstool//:toolchains \
                            --compiler=gcc \
-                           --linkopt=-l:libusb-1.0.so \
-                           --experimental_repo_remote_exec
+                           --linkopt=-l:libusb-1.0.so
 BAZEL_BUILD_OUTPUT_FILE_Linux := libedgetpu.so.1.0
 BAZEL_BUILD_OUTPUT_SYMLINK_Linux := libedgetpu.so.1
 
@@ -63,10 +62,10 @@ BAZEL_BUILD_OUTPUT_SYMLINK_Darwin := libedgetpu.1.dylib
 
 # Common parameters
 BAZEL_BUILD_FLAGS := --sandbox_debug --subcommands \
+  --experimental_repo_remote_exec \
   --compilation_mode=$(COMPILATION_MODE) \
   --define darwinn_portable=1 \
   --copt=-DSTRIP_LOG=1 \
-  --copt=-DEDGETPU_EXTERNAL_RELEASE_RUNTIME \
   --copt=-fno-rtti \
   --copt=-fno-exceptions \
   --copt='-D__FILE__=""' \
@@ -93,23 +92,66 @@ endef
 endif
 endif
 
+.PHONY: libedgetpu \
+        libedgetpu-direct \
+        libedgetpu-throttled \
+        workspace \
+        clean
+
 libedgetpu: libedgetpu-direct libedgetpu-throttled
 
-libedgetpu-direct:
+libedgetpu-direct: workspace
 	bazel build $(BAZEL_BUILD_FLAGS) $(BAZEL_BUILD_TARGET)
 	$(call copy_out,direct)
 	$(call strip_out,direct)
 
-libedgetpu-throttled:
+libedgetpu-throttled: workspace
 	bazel build $(BAZEL_BUILD_FLAGS) --copt=-DTHROTTLE_EDGE_TPU $(BAZEL_BUILD_TARGET)
 	$(call copy_out,throttled)
 	$(call strip_out,throttled)
 
+workspace: bazel/WORKSPACE bazel/$(WORKSPACE_PLATFORM_FILE)
+	cat $^ > WORKSPACE
+
 clean:
 	rm -rf $(OUT_DIR)
 
-ifdef DOCKER_MK
+################################################################################
+# Docker commands
+################################################################################
+DOCKER_CONTEXT_DIR := $(MAKEFILE_DIR)/docker
 DOCKER_WORKSPACE := $(MAKEFILE_DIR)
-DOCKER_TAG_BASE=coral-libedgetpu
-include $(DOCKER_MK)
-endif
+DOCKER_CONTAINER_WORKSPACE := /workspace
+DOCKER_CPUS ?= k8 armv7a armv6 aarch64
+DOCKER_TARGETS ?=
+DOCKER_IMAGE ?= debian:stretch
+DOCKER_TAG_BASE ?= libedgetpu-cross
+DOCKER_TAG := "$(DOCKER_TAG_BASE)-$(subst :,-,$(DOCKER_IMAGE))"
+DOCKER_SHELL_COMMAND ?=
+
+DOCKER_MAKE_COMMAND := \
+for cpu in $(DOCKER_CPUS); do \
+    make CPU=\$${cpu} -C $(DOCKER_CONTAINER_WORKSPACE) $(DOCKER_TARGETS) || exit 1; \
+done
+
+define docker_run_command
+chmod a+w /; \
+groupadd --gid $(shell id -g) $(shell id -g -n); \
+useradd -m -e '' -s /bin/bash --gid $(shell id -g) --uid $(shell id -u) $(shell id -u -n); \
+echo '$(shell id -u -n) ALL=(ALL) NOPASSWD:ALL' >> /etc/sudoers; \
+su $(shell id -u -n) $(if $(1),-c '$(1)',)
+endef
+
+docker-image:
+	docker build $(DOCKER_IMAGE_OPTIONS) -t $(DOCKER_TAG) \
+	    --build-arg IMAGE=$(DOCKER_IMAGE) $(DOCKER_CONTEXT_DIR)
+
+docker-shell: docker-image
+	docker run --rm -i --tty --workdir $(DOCKER_CONTAINER_WORKSPACE) \
+	    -v $(DOCKER_WORKSPACE):$(DOCKER_CONTAINER_WORKSPACE) \
+	    $(DOCKER_TAG) /bin/bash -c "$(call docker_run_command,$(DOCKER_SHELL_COMMAND))"
+
+docker-build: docker-image
+	docker run --rm -i $(shell tty -s && echo --tty) \
+	    -v $(DOCKER_WORKSPACE):$(DOCKER_CONTAINER_WORKSPACE) \
+	    $(DOCKER_TAG) /bin/bash -c "$(call docker_run_command,$(DOCKER_MAKE_COMMAND))"

README.md

@@ -6,7 +6,31 @@ This software is distributed in the binary form at [coral.ai/software](https://c
 
 ## Building
 
-At present only Bazel build system is supported, but it can be invoked from the Makefile. 
+At present only [Bazel](https://bazel.build/) build system is supported. For
+proper environment setup check `docker` directory.
+
+Build native binaries on Linux and macOS:
+```
+$ make
+```
+
+Build native binaries on Windows:
+```
+$ build.bat
+```
+
+Cross-compile for ARMv7-A (32 bit), and ARMv8-A (64 bit) on Linux:
+```
+$ CPU=armv7a make
+$ CPU=aarch64 make
+```
+
+Build Linux binaries inside Docker container (works on Linux and macOS):
+```
+$ DOCKER_CPUS="k8 armv7a aarch64" DOCKER_TARGETS=libedgetpu make docker-build
+```
+
+All built binaries go to the `out` directory.
 
 ## Support
 

api/watchdog.cc

@@ -86,8 +86,11 @@ util::StatusOr<int64> TimerFdWatchdog::Activate() {
     case WatchdogState::ACTIVE:
       break;  // Already active: Return old activation_id.
     case WatchdogState::BARKING:
-      return util::FailedPreconditionError(
-          "Cannot activate a barking watchdog.");
+      VLOG(1) << "A barking watchdog was re-activated.";
+      RETURN_IF_ERROR(timer_->Set(timeout_ns_));
+      state_ = WatchdogState::ACTIVE;
+      activation_id_ = GetNextActivationId(activation_id_);
+      break;
     case WatchdogState::INACTIVE:
       VLOG(5) << "Activating the watchdog.";
       RETURN_IF_ERROR(timer_->Set(timeout_ns_));
@@ -190,9 +193,11 @@ void TimerFdWatchdog::Watcher() {
       // Acquire lock again to update shared state after calling expire_.
       {
         StdMutexLock lock(&mutex_);
-        //  Watchdog might be destroyed while callback was running.
-        //  In that case, retain the 'DESTROYED' state.
-        if (state_ != WatchdogState::DESTROYED) {
+        // While the watchdog was executing the expire_ callback (ie BARKING):
+        //  If ~Watchdog was called, retain DESTROYED state.
+        //  If Activate was called (re-activated), retain ACTIVE state.
+        //  If Deactivate was called, state will change to INACTIVE now.
+        if (state_ == WatchdogState::BARKING) {
           state_ = WatchdogState::INACTIVE;
         }
       }

api/watchdog.h

@@ -162,7 +162,9 @@ class TimerFdWatchdog : public Watchdog {
   // The timer to be used for keeping track of expiration deadlines.
   std::unique_ptr<Timer> timer_;
 
-  // A single mutex to protect mutable fields in this class.
+  // A single mutex to protect mutable fields in this class. This mutex is not
+  // held while the watchdog callback is being executed. It is safe to signal,
+  // activate, deactivate or destroy a barking watchdog.
   std::mutex mutex_;
 
   // Watchdog state machine:
@@ -280,9 +282,11 @@ class CascadeWatchdog : public Watchdog {
   // A mutex to protect mutable class fields.
   std::mutex mutex_;
 
-  // Specifies which child watchdog is currently active. It can be used as an
-  // index to configs_ or watchdogs_. -1 means all watchdogs are inactive.
+  // Value that indicates all watchdogs are inactive.
   static constexpr int kNoneActive = -1;
+
+  // Specifies which child watchdog is currently active. A value other than
+  // kNoneActive can be used as an index to configs_ or watchdogs_.
   int currently_active_ GUARDED_BY(mutex_){kNoneActive};
 
   // The current/last generated activation ID for the caller of Activate on this

build.bat

@@ -15,6 +15,8 @@ echo off
 
 setlocal
 
+type bazel\WORKSPACE bazel\WORKSPACE.windows > WORKSPACE 2>NUL
+
 set THROTTLED=0
 set COMPILATION_MODE=opt
 set OUT_DIR=%~dp0\out
@@ -48,7 +50,8 @@ set BAZEL_BUILD_FLAGS= ^
 --define darwinn_portable=1 ^
 --copt=/DSTRIP_LOG=1 ^
 --copt=/DABSL_FLAGS_STRIP_NAMES ^
---copt=/DEDGETPU_EXTERNAL_RELEASE_RUNTIME ^
+--copt=/D_HAS_DEPRECATED_RESULT_OF ^
+--copt=/D_HAS_DEPRECATED_ADAPTOR_TYPEDEFS ^
 --copt=/GR- ^
 --copt=/DWIN32_LEAN_AND_MEAN ^
 --copt=/D_WINSOCKAPI_ ^

docker/Dockerfile

@@ -0,0 +1,38 @@
+ARG IMAGE
+FROM ${IMAGE}
+
+COPY update_sources.sh /
+RUN /update_sources.sh
+
+RUN dpkg --add-architecture armhf
+RUN dpkg --add-architecture arm64
+RUN apt-get update && apt-get install -y \
+  python \
+  python-future \
+  python-numpy \
+  build-essential \
+  crossbuild-essential-armhf \
+  crossbuild-essential-arm64 \
+  libusb-1.0-0-dev \
+  libusb-1.0-0-dev:arm64 \
+  libusb-1.0-0-dev:armhf \
+  zlib1g-dev \
+  zlib1g-dev:armhf \
+  zlib1g-dev:arm64 \
+  sudo \
+  pkg-config \
+  zip \
+  unzip \
+  curl \
+  wget \
+  git \
+  $(grep Ubuntu /etc/os-release > /dev/null && echo vim-common || echo xxd)
+
+RUN git clone https://github.com/raspberrypi/tools.git && \
+    cd tools && \
+    git reset --hard 4a335520900ce55e251ac4f420f52bf0b2ab6b1f
+
+ARG BAZEL_VERSION=3.2.0
+RUN wget -O /bazel https://github.com/bazelbuild/bazel/releases/download/${BAZEL_VERSION}/bazel-${BAZEL_VERSION}-installer-linux-x86_64.sh && \
+    bash /bazel && \
+    rm -f /bazel

docker/Dockerfile.windows

@@ -0,0 +1,42 @@
+FROM mcr.microsoft.com/windows/servercore:1903
+SHELL ["powershell", "-command"]
+
+# Install chocolatey + Win10 SDK + VS build tools
+RUN "Set-ExecutionPolicy Bypass -Scope Process -Force; iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))" 
+RUN choco install -y windows-sdk-10
+RUN choco install -y visualstudio2019buildtools
+RUN choco install -y visualstudio2019-workload-vctools
+RUN choco install -y python3
+RUN python -m pip install six numpy wheel
+
+# Install 7-zip
+RUN choco install -y 7zip
+RUN setx /M PATH $($Env:PATH + ';C:\Program Files\7-Zip')
+
+# Install msys2
+ARG MSYS_VERSION=20200602
+ADD http://repo.msys2.org/distrib/x86_64/msys2-base-x86_64-${MSYS_VERSION}.tar.xz c:/windows/temp
+RUN 7z.exe x c:\windows\temp\msys2-base-x86_64-$env:MSYS_VERSION.tar.xz
+RUN 7z.exe x c:\msys2-base-x86_64-$env:MSYS_VERSION.tar -o"c:\\"
+RUN setx /M PATH $($Env:PATH + ';C:\msys64\usr\bin')
+
+# Install patch
+ARG PATCH_VERSION=2.7.6-1
+ADD http://repo.msys2.org/msys/x86_64/patch-${PATCH_VERSION}-x86_64.pkg.tar.xz c:/windows/temp
+RUN 7z.exe x -y c:\windows\temp\patch-$env:PATCH_VERSION-x86_64.pkg.tar.xz
+RUN 7z.exe x -y c:\patch-$env:PATCH_VERSION-x86_64.pkg.tar -o"c:\\msys64"
+
+# Install vim (for xxd)
+ARG VIM_VERSION=8.2.0592-1
+ADD http://repo.msys2.org/msys/x86_64/vim-${VIM_VERSION}-x86_64.pkg.tar.xz c:/windows/temp
+RUN 7z.exe x -y c:\windows\temp\vim-$env:VIM_VERSION-x86_64.pkg.tar.xz
+RUN 7z.exe x -y c:\vim-$env:VIM_VERSION-x86_64.pkg.tar -o"c:\\msys64"
+
+# Install libusb release package
+ARG LIBUSB_VERSION=1.0.22
+ADD https://github.com/libusb/libusb/releases/download/v${LIBUSB_VERSION}/libusb-${LIBUSB_VERSION}.7z c:/windows/temp
+RUN 7z x -oc:\libusb-1.0.22 c:\windows\temp\libusb-1.0.22.7z
+
+# Install Bazel
+ARG BAZEL_VERSION=3.2.0
+ADD https://github.com/bazelbuild/bazel/releases/download/${BAZEL_VERSION}/bazel-${BAZEL_VERSION}-windows-x86_64.exe c:/windows/system32/bazel.exe

docker/update_sources.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+. /etc/os-release
+
+[[ "${NAME}" == "Ubuntu" ]] || exit 0
+
+sed -i "s/deb\ /deb \[arch=amd64\]\ /g" /etc/apt/sources.list
+
+cat <<EOT >> /etc/apt/sources.list
+deb [arch=arm64,armhf] http://ports.ubuntu.com/ubuntu-ports ${UBUNTU_CODENAME} main universe
+deb [arch=arm64,armhf] http://ports.ubuntu.com/ubuntu-ports ${UBUNTU_CODENAME}-updates main universe
+deb [arch=arm64,armhf] http://ports.ubuntu.com/ubuntu-ports ${UBUNTU_CODENAME}-security main universe
+EOT