Initial implementation of ccache caching for builds

Signed-off-by: Jesse Vincent <jesse@keyboard.io>

bin/kaleidoscope-builder

@@ -29,6 +29,7 @@ build_paths() {
     OUTPUT_DIR="${OUTPUT_DIR:-output/${LIBRARY}}"
     OUTPUT_PATH="${OUTPUT_PATH:-${SOURCEDIR}/${OUTPUT_DIR}}"
     STABLE_TEMP_DIR="${STABLE_TEMP_DIR:-/tmp/kaleidoscope-${USER}}"
+    CCACHE_WRAPPER_DIR="${CCACHE_WRAPPER_DIR:-${STABLE_TEMP_DIR}/ccache/bin}"
     CORE_CACHE_PATH="${CORE_CACHE_PATH:-${STABLE_TEMP_DIR}/arduino-cores}"
     
 
@@ -45,6 +46,24 @@ build_filenames () {
     ELF_FILE_PATH="${OUTPUT_PATH}/${OUTPUT_FILE_PREFIX}.elf"
 }
 
+
+enable_ccache () {
+    if  [ `which ccache` ]; then
+    if ! [ -d $CCACHE_WRAPPER_DIR ]; then
+	mkdir -p $CCACHE_WRAPPER_DIR
+	ln -s `which ccache` ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}gcc
+	ln -s `which ccache` ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}g++
+	ln -s ${AVR_NM} ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}nm
+	ln -s ${AVR_OBJCOPY} ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}objcopy
+	ln -s ${AVR_AR} ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}ar
+	ln -s ${AVR_SIZE} ${CCACHE_WRAPPER_DIR}/${COMPILER_PREFIX}size
+    fi
+    export CCACHE_PATH=${COMPILER_PATH}/
+    CCACHE_ENABLE="-prefs compiler.path=${CCACHE_WRAPPER_DIR}/"
+    fi
+}
+
+
 firmware_size () {
     if [ "${BOARD}" = "virtual" ]; then
         echo "[Size not computed for virtual build]"
@@ -193,6 +212,8 @@ compile () {
     build_version
     build_paths
     build_filenames
+    enable_ccache
+
     install -d "${OUTPUT_PATH}"
 
     echo "Building ${OUTPUT_DIR}/${SKETCH} (${LIB_VERSION}) ..."
@@ -247,6 +268,7 @@ compile () {
 	      -build-path "${BUILD_PATH}" \
 	      -ide-version "${ARDUINO_IDE_VERSION}" \
 	      -prefs "compiler.cpp.extra_flags=-std=c++11 -Woverloaded-virtual -Wno-unused-parameter -Wno-unused-variable -Wno-ignored-qualifiers ${ARDUINO_CFLAGS} ${LOCAL_CFLAGS}" \
+	      $CCACHE_ENABLE \
 	      -warnings all \
         ${ARDUINO_VERBOSE} \
 	      ${ARDUINO_AVR_GCC_PREFIX_PARAM} \

etc/kaleidoscope-builder.conf

@@ -147,6 +147,7 @@ COMPILER_PREFIX="${COMPILER_PREFIX:-avr-}"
 AVR_SIZE="${AVR_SIZE:-${COMPILER_PATH}/${COMPILER_PREFIX}size}"
 AVR_SIZE_FLAGS="${AVR_SIZE_FLAGS:--C --mcu=${MCU}}"
 AVR_OBJDUMP="${AVR_OBJDUMP:-${COMPILER_PATH}/${COMPILER_PREFIX}objdump}"
+AVR_OBJCOPY="${AVR_OBJCOPY:-${COMPILER_PATH}/${COMPILER_PREFIX}objcopy}"
 AVR_NM="${AVR_NM:-${COMPILER_PATH}/${COMPILER_PREFIX}nm}"
 AVR_AR="${AVR_AR:-${COMPILER_PATH}/${COMPILER_PREFIX}ar}"
 AVR_GCC="${AVR_GCC:-${COMPILER_PATH}/${COMPILER_PREFIX}gcc}"