ci/travis: Add a curl context

I arbitrarily picked Debian Jessie rather than duplicating
this matrix.  Not totally sure of the value of doing both
Ubuntu and Debian here for example.

.travis.yml

@@ -5,6 +5,7 @@ sudo: required
 env:
   - ci_distro=ubuntu ci_suite=trusty
   - ci_docker=debian:jessie-slim ci_distro=debian ci_suite=jessie
+  - ci_docker=debian:jessie-slim ci_distro=debian ci_suite=jessie ci_configopts="--with-curl"
   - ci_docker=debian:stretch-slim ci_distro=debian ci_suite=stretch
   - ci_docker=ubuntu:xenial ci_distro=ubuntu ci_suite=xenial
 

tests/ci-build.sh

@@ -52,13 +52,18 @@ NULL=
 # If yes, test failures break the build; if no, they are reported but ignored
 : "${ci_test_fatal:=yes}"
 
+# ci_configopts:
+# Additional args for configure
+: "${ci_configopts:=}"
+
 if [ -n "$ci_docker" ]; then
     exec docker run \
         --env=ci_docker="" \
         --env=ci_parallel="${ci_parallel}" \
         --env=ci_sudo=yes \
         --env=ci_test="${ci_test}" \
         --env=ci_test_fatal="${ci_test_fatal}" \
+        --env=ci_configopts="${ci_configopts}" \
         --privileged \
         ci-image \
         tests/ci-build.sh
@@ -81,6 +86,7 @@ make="make -j${ci_parallel} V=1 VERBOSE=1"
 ../configure \
     --enable-always-build-tests \
     --enable-installed-tests \
+    ${ci_configopts}
     "$@"
 
 ${make}

tests/ci-install.sh

@@ -50,6 +50,9 @@ NULL=
 # Typical values for ci_distro=fedora might be 25, rawhide
 : "${ci_suite:=jessie}"
 
+# ci_configopts: Additional arguments for configure
+: "${ci_configopts:=}"
+
 if [ $(id -u) = 0 ]; then
     sudo=
 else
@@ -104,6 +107,7 @@ case "$ci_distro" in
             libmount-dev \
             libselinux1-dev \
             libsoup2.4-dev \
+            libcurl4-openssl-dev \
             procps \
             zlib1g-dev \
             ${NULL}