1 files changed, 80 insertions, 0 deletions
diff --git a/scripts/env2string.awk b/scripts/env2string.awk
new file mode 100644
index 0000000000..57d0fc8f3b
--- /dev/null
+++ b/scripts/env2string.awk
@@ -0,0 +1,80 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright 2021 Google, Inc
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+# Awk script to parse a text file containing an environment and convert it
+# to a C string which can be compiled into U-Boot.
+
+# The resulting output is:
+#
+#   #define CONFIG_EXTRA_ENV_TEXT "<environment here>"
+#
+# If the input is empty, this script outputs a comment instead.
+
+BEGIN {
+	# env holds the env variable we are currently processing
+	env = "";
+	ORS = ""
+}
+
+# Skip empty lines, as these are generated by the clang preprocessor
+NF {
+	# Quote quotes
+	gsub("\"", "\\\"")
+
+	# Is this the start of a new environment variable?
+	if (match($0, "^([^ \t=][^ =]*)=(.*)$", arr)) {
+		if (length(env) != 0) {
+			# Record the value of the variable now completed
+			vars[var] = env
+		}
+		var = arr[1]
+		env = arr[2]
+
+		# Deal with += which concatenates the new string to the existing
+		# variable
+		if (length(env) != 0 && match(var, "^(.*)[+]$", var_arr))
+		{
+			# Allow var\+=val to indicate that the variable name is
+			# var+ and this is not actually a concatenation
+			if (substr(var_arr[1], length(var_arr[1])) == "\\") {
+				# Drop the backslash
+				sub(/\\[+]$/, "+", var)
+			} else {
+				var = var_arr[1]
+				env = vars[var] env
+			}
+		}
+	} else {
+		# Change newline to space
+		gsub(/^[ \t]+/, "")
+
+		# Don't keep leading spaces generated by the previous blank line
+		if (length(env) == 0) {
+			env = $0
+		} else {
+			env = env " " $0
+		}
+	}
+}
+
+END {
+	# Record the value of the variable now completed. If the variable is
+	# empty it is not set.
+	if (length(env) != 0) {
+		vars[var] = env
+	}
+
+	if (length(vars) != 0) {
+		printf("%s", "#define CONFIG_EXTRA_ENV_TEXT \"")
+
+		# Print out all the variables
+		for (var in vars) {
+			env = vars[var]
+			print var "=" vars[var] "\\0"
+		}
+		print "\"\n"
+	}
+}