travis: Add build with frozen versions for dependencies

.travis.yml

@@ -28,6 +28,12 @@ matrix:
       install: "./.travis/macos/deps.sh"
       script: "./.travis/macos/build.sh"
       after_success: "./.travis/macos/upload.sh"
+    - os: linux
+      env: NAME="linux build (frozen versions of dependencies)"
+      sudo: required
+      dist: trusty
+      services: docker
+      script: "./.travis/linux-frozen/build.sh"
 
 deploy:
   provider: releases

.travis/linux-frozen/build.sh

@@ -0,0 +1,4 @@
+#!/bin/bash -ex
+
+docker pull ubuntu:16.04
+docker run -v $(pwd):/citra ubuntu:16.04 /bin/bash -ex /citra/.travis/linux-frozen/docker.sh

.travis/linux-frozen/docker.sh

@@ -0,0 +1,27 @@
+#!/bin/bash -ex
+
+cd /citra
+
+apt-get update
+apt-get install -y build-essential wget git python-launchpadlib libssl-dev
+
+# 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.
+/citra/.travis/linux-frozen/install_package.py       \
+    libsdl2-dev 2.0.4+dfsg1-2ubuntu2 xenial          \
+    qtbase5-dev 5.2.1+dfsg-1ubuntu14.3 trusty        \
+    libqt5opengl5-dev 5.2.1+dfsg-1ubuntu14.3 trusty  \
+    libcurl4-openssl-dev 7.47.0-1ubuntu2.3 xenial    \
+    libicu52 52.1-3ubuntu0.6 trusty
+
+# Get a recent version of CMake
+wget https://cmake.org/files/v3.9/cmake-3.9.0-Linux-x86_64.sh
+echo y | sh cmake-3.9.0-Linux-x86_64.sh --prefix=cmake
+export PATH=/citra/cmake/cmake-3.9.0-Linux-x86_64/bin:$PATH
+
+mkdir build && cd build
+cmake .. -DUSE_SYSTEM_CURL=ON -DCMAKE_BUILD_TYPE=Release
+make -j4
+
+ctest -VV -C Release

.travis/linux-frozen/install_package.py

@@ -0,0 +1,38 @@
+#!/usr/bin/python
+
+import sys, re, subprocess
+from launchpadlib.launchpad import Launchpad
+
+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_link = 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']
+    deb_name = pkg[0] + '_' + pkg[1] + '_amd64.deb'
+    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 ' + deb_file + ' | grep -oP "^ Depends\: \K.*$"'])
+    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 ' + 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'] + deb_file_list)