1 files changed, 50 insertions, 0 deletions
diff --git a/bin/mi5.awk b/bin/mi5.awk
new file mode 100644
index 00000000..c05955ff
--- /dev/null
+++ b/bin/mi5.awk
@@ -0,0 +1,50 @@
+# Crude m4 preprocessor
+BEGIN { mac = 0 }
+
+# Print an m4 opener as the first byte
+NR == 1 { printf "`" }
+
+# Blocks
+NF == 1 && $1 == "<%" && !mac {
+    mac = 1
+    printf "'"
+    next
+}
+NF == 1 && $1 == "%>" && mac {
+    mac = 0
+    printf "`"
+    next
+}
+
+# If processing macros, strip leading and trailing whitespace and skip blank
+# lines
+mac {
+    sub(/^ */, "")
+    sub(/ *$/, "")
+}
+mac && !NF { next }
+
+# Inlines
+mac {
+    print $0 "dnl"
+}
+!mac {
+
+    # Don't let apostrophes close the comment
+    gsub(/'/, "''`")
+
+    # Don't let $ signs confound expansion
+    gsub(/\$/, "$'`")
+
+    # Replace m5 opener with m4 closer
+    gsub(/<% */, "'")
+
+    # Replace m5 closer with m4 opener
+    gsub(/ *%>/, "`")
+    print
+}
+
+# Print an m4 closer and newline deleter as the last bytes
+END {
+    print "'dnl"
+}