Merge remote-tracking branch 'org/master'

* org/master:
  Enable Travis CI with basic Docker build testing
  Properly cleanup apk build dependency in Dockerfile
  Use multi-thread to "make" in Dockerfile to speedup build
  Specify git clone depth in Dockerfile to speed up git cloning
  Clone libsodium with specify single branch in Dockerfile
  Replace apk parameter `--update` with `--no-cache` to reduce size

.travis.yml

@@ -0,0 +1,14 @@
+---
+
+dist: xenial
+
+language: minimal
+
+git:
+  depth: 5
+
+script:
+  - docker build -t dnscrypt-server-docker-ci-test .
+
+services:
+  - docker

Dockerfile

@@ -6,38 +6,41 @@ ENV BUILD_DEPS   make gcc musl-dev git libevent-dev expat-dev shadow autoconf fi
 ENV RUNTIME_DEPS bash util-linux coreutils findutils grep openssl ldns ldns-tools libevent expat libexecinfo coreutils drill ca-certificates
 
 RUN set -x && \
-    apk --update upgrade && apk add --no-cache $RUNTIME_DEPS $BUILD_DEPS && \
+    apk --no-cache upgrade && apk add --no-cache $RUNTIME_DEPS && \
     update-ca-certificates 2> /dev/null || true
 
 ENV UNBOUND_GIT_URL https://github.com/jedisct1/unbound.git
 ENV UNBOUND_GIT_REVISION 7bd08b7a9987a0780892131f8590b6e384194bbc
 
 RUN set -x && \
+    apk add --no-cache $BUILD_DEPS && \
     mkdir -p /tmp/src && \
     cd /tmp/src && \
-    git clone "$UNBOUND_GIT_URL" && \
+    git clone --depth=1000 "$UNBOUND_GIT_URL" && \
     cd unbound && \
     git checkout "$UNBOUND_GIT_REVISION" && \
     groupadd _unbound && \
     useradd -g _unbound -s /etc -d /dev/null _unbound && \
     ./configure --prefix=/opt/unbound --with-pthreads \
     --with-username=_unbound --with-libevent --enable-event-api && \
-    make install && \
+    make -j$(getconf _NPROCESSORS_ONLN) install && \
     mv /opt/unbound/etc/unbound/unbound.conf /opt/unbound/etc/unbound/unbound.conf.example && \
+    apk del --purge $BUILD_DEPS && \
     rm -fr /opt/unbound/share/man && \
     rm -fr /tmp/* /var/tmp/*
 
 ENV LIBSODIUM_GIT_URL https://github.com/jedisct1/libsodium.git
 
 RUN set -x && \
+    apk add --no-cache $BUILD_DEPS && \
     mkdir -p /tmp/src && \
     cd /tmp/src && \
-    git clone "$LIBSODIUM_GIT_URL" && \
+    git clone --depth=1 --branch stable "$LIBSODIUM_GIT_URL" && \
     cd libsodium && \
-    git checkout stable && \
     env CFLAGS=-Ofast ./configure --disable-dependency-tracking && \
-    make check && make install && \
+    make -j$(getconf _NPROCESSORS_ONLN) check && make -j$(getconf _NPROCESSORS_ONLN) install && \
     ldconfig /usr/local/lib && \
+    apk del --purge $BUILD_DEPS && \
     rm -fr /tmp/* /var/tmp/*
 
 ENV DNSCRYPT_WRAPPER_GIT_URL https://github.com/jedisct1/dnscrypt-wrapper.git
@@ -46,9 +49,10 @@ ENV DNSCRYPT_WRAPPER_GIT_BRANCH xchacha-stamps
 COPY queue.h /tmp
 
 RUN set -x && \
+    apk add --no-cache $BUILD_DEPS && \
     mkdir -p /tmp/src && \
     cd /tmp/src && \
-    git clone --branch=${DNSCRYPT_WRAPPER_GIT_BRANCH} ${DNSCRYPT_WRAPPER_GIT_URL} && \
+    git clone --depth=1 --branch=${DNSCRYPT_WRAPPER_GIT_BRANCH} ${DNSCRYPT_WRAPPER_GIT_URL} && \
     cd dnscrypt-wrapper && \
     sed -i 's#<sys/queue.h>#"/tmp/queue.h"#' compat.h && \
     sed -i 's#HAVE_BACKTRACE#NO_BACKTRACE#' compat.h && \
@@ -57,13 +61,13 @@ RUN set -x && \
     useradd -g _dnscrypt-wrapper -s /etc -d /opt/dnscrypt-wrapper/empty _dnscrypt-wrapper && \
     groupadd _dnscrypt-signer && \
     useradd -g _dnscrypt-signer -G _dnscrypt-wrapper -s /etc -d /dev/null _dnscrypt-signer && \
-    make configure && \
+    make -j$(getconf _NPROCESSORS_ONLN) configure && \
     env CFLAGS=-Ofast ./configure --prefix=/opt/dnscrypt-wrapper && \
-    make install && \
+    make -j$(getconf _NPROCESSORS_ONLN) install && \
+    apk del --purge $BUILD_DEPS && \
     rm -fr /tmp/* /var/tmp/*
 
 RUN set -x && \
-    echo apk del --purge $BUILD_DEPS && \
     echo rm -rf /tmp/* /var/tmp/* /usr/local/include
 
 RUN mkdir -p \