Problem: no code coverage in CI

Solution: add new coverage build, and upload results to coveralls.io

.travis.yml

@@ -12,6 +12,12 @@ env:
 - BUILD_TYPE=cmake CURVE=tweetnacl
 - BUILD_TYPE=default CURVE=libsodium
 - BUILD_TYPE=default
+- BUILD_TYPE=coverage CURVE=tweetnacl
+
+matrix:
+  exclude:
+    -  env: BUILD_TYPE=coverage CURVE=tweetnacl
+       os: osx
 
 sudo: false
 
@@ -21,6 +27,7 @@ addons:
     - kubuntu-backports
     packages:
     - cmake
+    - lcov
 
 before_install:
 - if [ $TRAVIS_OS_NAME == "osx" ] ; then brew update; brew install binutils ; fi

builds/coverage/ci_build.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+
+set -x
+
+mkdir tmp
+BUILD_PREFIX=$PWD/tmp
+
+CONFIG_OPTS=()
+CONFIG_OPTS+=("CFLAGS=-I${BUILD_PREFIX}/include")
+CONFIG_OPTS+=("CPPFLAGS=-I${BUILD_PREFIX}/include")
+CONFIG_OPTS+=("CXXFLAGS=-I${BUILD_PREFIX}/include")
+CONFIG_OPTS+=("LDFLAGS=-L${BUILD_PREFIX}/lib")
+CONFIG_OPTS+=("PKG_CONFIG_PATH=${BUILD_PREFIX}/lib/pkgconfig")
+CONFIG_OPTS+=("--prefix=${BUILD_PREFIX}")
+CONFIG_OPTS+=("--enable-code-coverage")
+
+if [ -z $CURVE ]; then
+    CMAKE_OPTS+=("-DENABLE_CURVE=OFF")
+elif [ $CURVE == "libsodium" ]; then
+    CMAKE_OPTS+=("-DWITH_LIBSODIUM=ON")
+
+    git clone --depth 1 -b stable git://github.com/jedisct1/libsodium.git
+    ( cd libsodium; ./autogen.sh; ./configure --prefix=$BUILD_PREFIX; make install)
+fi
+
+pip install --user cpp-coveralls
+
+# Build, check, and install from local source
+( cd ../..; ./autogen.sh && ./configure "${CONFIG_OPTS[@]}" && make -j5 && make check && coveralls --exclude tests --gcov-options '\-lp') || exit 1