docker: Lock image build

Author: madadam

docker/linux.sh

@@ -139,8 +139,14 @@ function print_help() {
 function build_container() {
     log_group_begin "Building image $image_name"
 
-    ndk_version=$(cat ndk-version.txt)
-    dock build -t $image_name --build-arg NDK_VERSION=$ndk_version - < docker/Dockerfile.linux
+    local ndk_version=$(cat ndk-version.txt)
+
+    flock --exclusive docker/Dockerfile.linux \
+        docker $(docker_host) build \
+            --tag $image_name \
+            --file docker/Dockerfile.linux \
+            --build-arg NDK_VERSION=$ndk_version \
+            docker
 
     log_group_end
 }

docker/utils.sh

@@ -24,14 +24,16 @@ function check_dependency {
     command -v $dep >/dev/null 2>&1 || { error "'$dep' is not installed"; }
 }
 
-function dock() {
+function docker_host() {
     if [ -n "$host" ]; then
-        docker --host ssh://$host "$@"
-    else
-        docker "$@"
+        echo -n "--host ssh://$host"
     fi
 }
 
+function dock() {
+    docker $(docker_host) "$@"
+}
+
 function exe() (
     local opts=
     local history_log=