From: Nick Bowler <nbowler@draconx.ca>
Date: Sun, 8 Jan 2023 04:19:18 +0000 (-0500)
Subject: gen-options.awk: Work around busybox regex bug.
X-Git-Url: http://git.draconx.ca/gitweb/dxcommon.git/commitdiff_plain/0a296c1808200072deea6285f3e9992fca6095dd

gen-options.awk: Work around busybox regex bug.

It appears that busybox awk does not recognize \] in a character class,
interpreting the backslash literally and taking the ] as the end of the
character class:

  % printf '%s\n' ']' '\]' | busybox awk '/^[\]]$/ { print; }'
  \]

  % printf '%s\n' ']' '\]' | gawk '/^[\]]$/ { print; }'
  ]

Busybox does accept []] as meaning "] is part of the character class",
but this syntax is not portable to heirloom (and presumably also Solaris
10) awk, which only works with [\]].  GNU awk accepts either form.

So instead, let's avoid this problematic construct entirely by writing
the test in a different way.
---

diff --git a/scripts/gen-options.awk b/scripts/gen-options.awk
index f1dbb1c..a93c47c 100755
--- a/scripts/gen-options.awk
+++ b/scripts/gen-options.awk
@@ -152,7 +152,7 @@ $0 ~ /^-/ {
   }
 
   # Extract argument name
-  if (work ~ /^\[=[^\] \t]+\]/) {
+  if (work ~ /^\[=[^ \t]+\]/ && sub(/\]/, "&", work) == 1) {
     if (n = index(work, "]")) {
       arg = substr(work, 3, n-3)
       work = substr(work, n+1)