Build system: add single threaded mode

README.md

@@ -55,8 +55,10 @@ This will download the following dependenceis:
 To build the project, just use the `build` alias or invoke the `build.sh`
 script from the project's base directory.
 
-`build` and `build.sh` accept the environment variables `CXX` and `CXXFLAGS`.
-`CXXFLAGS` must at least specify the C++ version.
+`build` and `build.sh` accept the environment variables `CXX`, `CXXFLAGS`, and `SINGLE`.
+
+- `CXXFLAGS` must at least specify the C++ version.
+- Set `SINGLE` to `yes` to run the build script in single-threaded mode.
 
 To clean out the build or dependency directories, use `clean` and
 `clean_dependencies` or their corresponding scripts respectively.

scripts/build.sh

@@ -15,6 +15,13 @@
 # version 3 along with this program.
 # If not, see https://www.gnu.org/licenses/agpl-3.0.en.html
 
+if [ "$(tr '[:upper:]' '[:lower:]' <<< $SINGLE)" = "yes" ]; then
+    echo "Running build script in single-threaded mode."
+    WAIT_ANYWAY="wait"
+else
+    WAIT_ANYWAY=""
+fi
+
 if [ -z "$CXX" ]; then
     CXX="c++"
 fi
@@ -45,6 +52,7 @@ for lib in $(find ./src/lib -name "*.cpp"); do
     COMPILE_COMMAND="$CXX_WITH_FLAGS -fPIC -shared -o $(sed -e 's/^.\/src/.\/bin/;s/cpp$/so/' <<< $lib) $lib"
     echo $COMPILE_COMMAND
     $COMPILE_COMMAND &
+    $WAIT_ANYWAY
 done
 
 wait
@@ -69,6 +77,7 @@ COMPILE_COMMANDS=(
 for command in ${!COMPILE_COMMANDS[@]}; do
     echo "${COMPILE_COMMANDS[command]}"
     ${COMPILE_COMMANDS[command]} &
+    $WAIT_ANYWAY
 done
 
 wait

setupenv.bashrc

@@ -29,7 +29,7 @@ function run_tests {
 
 function build {
     pushd "$PROJECT_BASE_DIR" >/dev/null 2>&1
-    CXX="$CXX" CXXFLAGS="$CXXFLAGS" scripts/build.sh
+    SINGLE="$SINGLE" CXX="$CXX" CXXFLAGS="$CXXFLAGS" scripts/build.sh
     popd >/dev/null 2>&1
 }