Add Dockerfile for building and running local Skia checkout with SwiftShader

This also adds a little helper to fuzz that allows us to see what
GPU is being targeted.

This is the first step in getting a SwiftShader fuzz target.

To prove that this works, simply download this patch and run:

./docker/skia-with-swift-shader-base/build-with-swift-shader-and-run "out/with-swift-shader/fuzz --gpuInfo -t api -n NativeGLCanvas -b out/with-swift-shader/fiddle"
Running supplied command ['out/with-swift-shader/fuzz', '--gpuInfo', '-t', 'api', '-n', 'NativeGLCanvas', '-b', 'out/with-swift-shader/fiddle']
Fuzzing NativeGLCanvas...
GL_RENDERER Google SwiftShader
GL_VENDOR Google Inc.
GL_VERSION OpenGL ES 3.0 SwiftShader 4.0.0.6

Bug: skia:
Change-Id: I3cc11a6bcd14f70f6025011722f9a73c94cb1f65
Reviewed-on: https://skia-review.googlesource.com/132269
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>

4 files changed, 139 insertions, 1 deletions

diff --git a/docker/README.md b/docker/README.md
index c237c61795..41c2a39346 100644
--- a/docker/README.md
+++ b/docker/README.md
@@ -3,12 +3,35 @@ Docker
 
 Docker files for building different Skia targets.
 
-Manual
+skia-release
 ------
 
+This image is used to build Skia at TOT with SwiftShader.
+
 There is a continuous process that builds this docker image, but if you
 need to manually push a verison, then run the following commands:
 
     docker build -t skia-release ./docker/skia-release/
     docker tag skia-release gcr.io/skia-public/skia-release:prod
     docker push gcr.io/skia-public/skia-release:prod
+
+
+skia-with-swift-shader-base
+------
+
+This image is used to build a local checkout of Skia with SwiftShader and run the built
+executables without requiring the SwiftShader be installed on the host.
+
+For example (see build-with-swift-shader-and-run for more info), to reproduce a
+fuzzer bug in SwiftShader:
+
+    # First, copy the test case into $SKIA_ROOT, say $SKIA_ROOT/skbug_1234
+    build-with-swift-shader-and-run "out/with-swift-shader/fuzz -t filter_fuzz -b /skia/skbug_1234"
+
+There is a continuous process that builds this docker image (which only really changes
+if SwiftShader is updated), but if you need to manually push a version, then run the
+following commands:
+
+    docker build -t skia-with-swift-shader-base ./docker/skia-with-swift-shader-base/
+    docker tag skia-with-swift-shader-base gcr.io/skia-public/skia-with-swift-shader-base:prod
+    docker push gcr.io/skia-public/skia-with-swift-shader-base:prod
\ No newline at end of file
diff --git a/docker/skia-with-swift-shader-base/Dockerfile b/docker/skia-with-swift-shader-base/Dockerfile
new file mode 100644
index 0000000000..953d375d63
--- /dev/null
+++ b/docker/skia-with-swift-shader-base/Dockerfile
@@ -0,0 +1,18 @@
+# Dockerfile for building Skia in release mode, using 3rd party libs from DEPS, with SwiftShader.
+FROM launcher.gcr.io/google/clang-debian9 AS build
+RUN apt-get update && apt-get upgrade -y && apt-get install -y \
+  git \
+  python \
+  curl \
+  build-essential \
+  libfontconfig-dev \
+  libgl1-mesa-dev \
+  libglu1-mesa-dev
+
+ADD https://storage.googleapis.com/swiftshader-binaries/OpenGL_ES/Latest/Linux/libGLESv2.so /usr/local/lib/libGLESv2.so
+ADD https://storage.googleapis.com/swiftshader-binaries/OpenGL_ES/Latest/Linux/libEGL.so /usr/local/lib/libEGL.so
+RUN cd /tmp \
+  && git clone 'https://chromium.googlesource.com/chromium/tools/depot_tools.git' \
+  && git clone https://swiftshader.googlesource.com/SwiftShader swiftshader
+
+RUN mkdir -m 0777 /skia
\ No newline at end of file
diff --git a/docker/skia-with-swift-shader-base/build-with-swift-shader-and-run b/docker/skia-with-swift-shader-base/build-with-swift-shader-and-run
new file mode 100755
index 0000000000..3fd96afe89
--- /dev/null
+++ b/docker/skia-with-swift-shader-base/build-with-swift-shader-and-run
@@ -0,0 +1,61 @@
+#!/usr/bin/python
+
+import subprocess
+import os
+import argparse
+
+
+# This script compiles and runs a skia app using Swiftshader in a docker container, making it easy
+# to use Swiftshade w/o having to over-write /usr/local/lib/libEGL.so and related on the
+# host development machine.
+
+# The Skia repo to be compiled will be the one on the host machine, which will
+# default to the one specified by the environment variable $SKIA_ROOT with a fallback to the
+# current working directory.
+
+# Example usage
+
+# Prove SwiftShader is really being used:
+#   build-with-swift-shader-and-run "out/with-swift-shader/fuzz --gpuInfo -t api -n NativeGLCanvas"
+
+# Notice the output says GL_RENDERER Google SwiftShader
+# After running the above, feel free to check out $SKIA_OUT/out/with-swift-shader. It has binaries
+# but if you try to run out/with-swift-shader/fuzz --gpuInfo -t api -n NativeGLCanvas w/o using
+# Docker, it will use the host's GPU (e.g. GL_VENDOR NVIDIA Corporation).
+
+# Reproduce a fuzzer bug in SwiftShader:
+# First, copy the test case into $SKIA_ROOT, say $SKIA_ROOT/skbug_1234
+#    build-with-swift-shader-and-run "out/with-swift-shader/fuzz -t filter_fuzz -b /skia/skbug_1234"
+
+# $SKIA_ROOT gets mapped to /skia - other than that, the docker container does not have
+# access to the host file system.
+
+
+IMAGE = 'gcr.io/skia-public/skia-with-swift-shader-base:prod'
+
+BUILD_SCRIPT_PATH = '/skia/docker/skia-with-swift-shader-base/build.sh'
+EXECUTABLE_DIR = 'out/with-swift-shader/'
+
+parser = argparse.ArgumentParser()
+parser.add_argument('--sync_deps', action='store_true', help='Sync the deps before building?')
+parser.add_argument('command', help='A string containing the command to be run '
+                                    '(e.g. out/with-swift-shader/fuzz --help)')
+args = parser.parse_args()
+
+skia_root = os.environ['SKIA_ROOT'] or os.getcwd()
+
+print 'Assuming SKIA_ROOT to be %s' % skia_root
+
+build_cmd = ['docker', 'run', '--rm', '-v', '%s:/skia' % skia_root, IMAGE, BUILD_SCRIPT_PATH]
+if args.sync_deps:
+    build_cmd += ['sync-deps']
+
+print 'Compiling executables to %s/%s' % (skia_root, EXECUTABLE_DIR)
+
+print subprocess.check_output(build_cmd)
+
+supplied_cmd = args.command.split(' ')
+print 'Running supplied command %s' % supplied_cmd
+run_cmd = ['docker', 'run', '--rm', '-w=/skia', '-v', '%s:/skia' % skia_root, IMAGE] + supplied_cmd
+
+print subprocess.check_output(run_cmd)
\ No newline at end of file
diff --git a/docker/skia-with-swift-shader-base/build.sh b/docker/skia-with-swift-shader-base/build.sh
new file mode 100755
index 0000000000..cabd931948
--- /dev/null
+++ b/docker/skia-with-swift-shader-base/build.sh
@@ -0,0 +1,36 @@
+#!/bin/sh
+# Copyright 2018 Google, LLC
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+
+set +e
+
+mkdir -p /skia/out/with-swift-shader
+
+echo '
+cc = "clang"
+cxx = "clang++"
+skia_use_egl = true
+is_debug = false
+skia_use_system_freetype2 = false
+extra_cflags = [
+  "-I/tmp/swiftshader/include",
+  "-DGR_EGL_TRY_GLES3_THEN_GLES2",
+  "-g0",
+]
+extra_ldflags = [
+  "-L/usr/local/lib",
+  "-Wl,-rpath",
+  "-Wl,/usr/local/lib"
+] ' > /skia/out/with-swift-shader/args.gn
+
+# /skia is where the host Skia checkout is linked to in the container
+cd /skia
+if [ "sync-deps" = "$1" ]; then
+    python tools/git-sync-deps
+fi
+./bin/fetch-gn
+./bin/gn gen out/with-swift-shader
+/tmp/depot_tools/ninja -C out/with-swift-shader