TRITON-2159 Port /lib/sdc/config.sh to linux

proto/usr/triton/config/config.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/bash
+#
+# functions for getting USB headnode config values (intended to be sourced
+# from other scripts)
+#
+# It is also possible to use this to get a JSON hash of the config options using:
+#
+# bash config.sh -json
+#
+# Copyright 2020 Joyent Inc.
+#
+
+# Sets SDC_CONFIG_FILENAME with the location of the config file.
+# On linux this is always the same, this function is here for
+# compatibility purposes
+function load_sdc_config_filename {
+    # the default
+    COMPUTE_NODE_CONFIG_FILENAME="/usr/triton/config/node.config"
+    SDC_CONFIG_FILENAME=${COMPUTE_NODE_CONFIG_FILENAME}
+    SDC_CONFIG_INC_DIR="$(dirname ${COMPUTE_NODE_CONFIG_FILENAME})"
+
+}
+
+
+# Loads config variables with prefix (default: CONFIG_)
+function load_sdc_config {
+
+    prefix=$1
+    [[ -z ${prefix} ]] && prefix="CONFIG_"
+
+    load_sdc_config_filename
+    if [[ -f ${SDC_CONFIG_INC_DIR}/generic ]]; then
+        GEN_FILE=${SDC_CONFIG_INC_DIR}/generic
+    else
+        GEN_FILE=/dev/null
+    fi
+
+    # Ignore comments, spaces at the beginning of lines and lines that don't
+    # start with a letter.
+    eval $((cat ${GEN_FILE} ${SDC_CONFIG_FILENAME}; echo "config_inc_dir=${SDC_CONFIG_INC_DIR}") | \
+        sed -e "s/^ *//" | grep -v "^#" | grep "^[a-zA-Z]" | \
+        sed -e "s/^/${prefix}/")
+}