Add travis CI config

This will let us setup travis-ci on the Breakpad GitHub mirror.

R=vapier@chromium.org, mark@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1873133003 .

.travis.yml

@@ -0,0 +1,26 @@
+# Travis build integration.
+# https://docs.travis-ci.com/
+language: cpp
+# TODO: add a clang build as well.
+compiler:
+ - gcc
+addons:
+  apt:
+    sources:
+      - ubuntu-toolchain-r-test
+    packages:
+      - gcc-4.8
+      - g++-4.8
+# Travis sets CC/CXX to the system toolchain based on the `compiler`
+# selection. If clang is added, this should move to be set inside the
+# matrix.
+env:
+  - USE_CC=gcc-4.8 USE_CXX=g++-4.8
+before_install: ./scripts/travis-checkout.sh
+script: ./scripts/travis-build.sh
+# TODO: add mac support
+os:
+  - linux
+notifications:
+  email:
+    - google-breakpad-dev@googlegroups.com

scripts/travis-build.sh

@@ -0,0 +1,32 @@
+#!/bin/sh
+
+set -ex
+
+setup_env() {
+  # Travis sets CC/CXX to the system toolchain, so our .travis.yml
+  # exports USE_{CC,CXX} for this script to use.
+  if [ -n "$USE_CC" ]; then
+      export CC=$USE_CC
+  fi
+  if [ -n "$USE_CXX" ]; then
+      export CXX=$USE_CXX
+  fi
+  # Use -jN for faster builds. Travis build machines under Docker
+  # have a lot of cores, but are memory-limited, so the kernel
+  # will OOM if we try to use them all, so use at most 4.
+  # See https://github.com/travis-ci/travis-ci/issues/1972
+  export NCPUS=$(getconf _NPROCESSORS_ONLN)
+  export JOBS=$(( $NCPUS < 4 ? $NCPUS : 4 ))
+}
+
+build() {
+  ./configure
+  make -j${JOBS} check
+}
+
+main() {
+  setup_env
+  build
+}
+
+main "$@"

scripts/travis-checkout.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+set -ex
+
+get_depot_tools() {
+  cd
+  git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
+  PATH="$HOME/depot_tools:$PATH"
+}
+
+gclient_sync() {
+  # Rename the source dir to match what gclient expects.
+  srcdir=$(basename "$TRAVIS_BUILD_DIR")
+  cd "${TRAVIS_BUILD_DIR}"/..
+  mv "${srcdir}" src
+  gclient config --unmanaged https://github.com/google/breakpad.git
+  gclient sync
+}
+
+main() {
+  get_depot_tools
+  gclient_sync
+}
+
+main "$@"