env: Avoid using GNU features in awk

GNU has a very useful third argument to match() but this is not supported
in the POSIX awk.

Update the code to cope, so that the script is POSIX-compliant.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Mark Kettenis <mark.kettenis@xs4all.nl>

diff --git a/scripts/env2string.awk b/scripts/env2string.awk
index 57d0fc8..1bfe9ed 100644 (file)
--- a/scripts/env2string.awk
+++ b/scripts/env2string.awk
@@ -21,29 +21,39 @@ BEGIN {
 
 # Skip empty lines, as these are generated by the clang preprocessor
 NF {
+       do_output = 0
+
        # Quote quotes
        gsub("\"", "\\\"")
 
+       # Avoid using the non-POSIX third parameter to match(), by splitting
+       # the work into several steps.
+       has_var = match($0, "^([^ \t=][^ =]*)=(.*)$")
+
        # Is this the start of a new environment variable?
-       if (match($0, "^([^ \t=][^ =]*)=(.*)$", arr)) {
+       if (has_var) {
                if (length(env) != 0) {
                        # Record the value of the variable now completed
                        vars[var] = env
+                       do_output = 1
                }
-               var = arr[1]
-               env = arr[2]
+
+               # Collect the variable name. The value follows the '='
+               match($0, "^([^ \t=][^ =]*)=")
+               var = substr($0, 1, RLENGTH - 1)
+               env = substr($0, RLENGTH + 1)
 
                # Deal with += which concatenates the new string to the existing
-               # variable
-               if (length(env) != 0 && match(var, "^(.*)[+]$", var_arr))
-               {
+               # variable. Again we are careful to use POSIX match()
+               if (length(env) != 0 && match(var, "^(.*)[+]$")) {
+                       plusname = substr(var, RSTART, RLENGTH - 1)
                        # 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])) == "\\") {
+                       if (substr(plusname, length(plusname)) == "\\") {
                                # Drop the backslash
                                sub(/\\[+]$/, "+", var)
                        } else {
-                               var = var_arr[1]
+                               var = plusname
                                env = vars[var] env
                        }
                }
@@ -65,9 +75,10 @@ END {
        # empty it is not set.
        if (length(env) != 0) {
                vars[var] = env
+               do_output = 1
        }
 
-       if (length(vars) != 0) {
+       if (do_output) {
                printf("%s", "#define CONFIG_EXTRA_ENV_TEXT \"")
 
                # Print out all the variables