Add Linux build with frozen dependencies

.travis.yml

@@ -20,6 +20,12 @@ matrix:
       install: "./.travis/linux/deps.sh"
       script: "./.travis/linux/build.sh"
       after_success: "./.travis/linux/upload.sh"
+    - os: linux
+      env: NAME="linux build (frozen versions of dependencies)"
+      sudo: required
+      dist: trusty
+      services: docker
+      script: "./.travis/linux-frozen/build.sh"
     - os: osx
       env: NAME="macos build"
       sudo: false

.travis/linux-frozen/build.sh

@@ -0,0 +1,5 @@
+#!/bin/bash -ex
+mkdir -p "$HOME/.ccache"
+docker pull ubuntu:18.04
+docker run -v $(pwd):/yuzu -v "$HOME/.ccache":/root/.ccache ubuntu:18.04 /bin/bash -ex /yuzu/.travis/linux-frozen/docker.sh
+

.travis/linux-frozen/docker.sh

@@ -0,0 +1,22 @@
+#!/bin/bash -ex
+
+cd /yuzu
+
+apt-get update
+apt-get install -y build-essential wget git python-launchpadlib ccache
+
+# Install specific versions of packages with their dependencies
+# The apt repositories remove older versions regularly, so we can't use
+# apt-get and have to pull the packages directly from the archives.
+/yuzu/.travis/linux-frozen/install_package.py       \
+    libsdl2-dev 2.0.7+dfsg1-3ubuntu1 bionic          \
+    qtbase5-dev 5.9.3+dfsg-0ubuntu2 bionic           \
+    libqt5opengl5-dev 5.9.3+dfsg-0ubuntu2 bionic     \
+    libicu57 57.1-6ubuntu0.2 bionic                  \
+    cmake 3.10.2-1ubuntu2 bionic
+
+mkdir build && cd build
+cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/lib/ccache/gcc -DCMAKE_CXX_COMPILER=/usr/lib/ccache/g++
+make -j4
+
+ctest -VV -C Release

.travis/linux-frozen/install_package.py

@@ -0,0 +1,52 @@
+#!/usr/bin/python
+
+import sys
+import re
+import subprocess
+from launchpadlib.launchpad import Launchpad
+
+if sys.version_info[0] > 2:
+    xrange = range
+
+cachedir = '/.launchpadlib/cache/'
+launchpad = Launchpad.login_anonymously(
+    'grab build info', 'production', cachedir, version='devel')
+
+processed_packages = []
+deb_file_list = []
+
+
+def get_url(pkg, distro):
+    build_ref = launchpad.archives.getByReference(reference='ubuntu').getPublishedBinaries(
+        binary_name=pkg[0], distro_arch_series='https://api.launchpad.net/devel/ubuntu/' + distro + '/amd64', version=pkg[1], exact_match=True, order_by_date=True).entries[0]
+    build_link = build_ref['build_link']
+    deb_name = '{}_{}_{}.deb'.format(pkg[0], pkg[1], 'amd64' if build_ref['architecture_specific'] else 'all')
+    deb_link = build_link + '/+files/' + deb_name
+    return [deb_link, deb_name]
+
+
+def list_dependencies(deb_file):
+    t = subprocess.check_output(
+        ['bash', '-c', '(dpkg -I {} | grep -oP "^ Depends\: \K.*$") || true'.format(deb_file)])
+    deps = [i.strip() for i in t.split(',')]
+    equals_re = re.compile(r'^(.*) \(= (.*)\)$')
+    return [equals_re.sub(r'\1=\2', i).split('=') for i in filter(equals_re.match, deps)]
+
+
+def get_package(pkg, distro):
+    if pkg in processed_packages:
+        return
+    print('Getting {}...'.format(pkg[0]))
+    url = get_url(pkg, distro)
+    subprocess.check_call(['wget', '--quiet', url[0], '-O', url[1]])
+    for dep in list_dependencies(url[1]):
+        get_package(dep, distro)
+    processed_packages.append(pkg)
+    deb_file_list.append('./' + url[1])
+
+
+for i in xrange(1, len(sys.argv), 3):
+    get_package([sys.argv[i], sys.argv[i + 1]], sys.argv[i + 2])
+
+subprocess.check_call(
+['apt-get', 'install', '-y', '--force-yes'] + deb_file_list)