Document the big regex
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/scripts/generate_errors.pl b/scripts/generate_errors.pl
index 33b14ee..ecf552e 100755
--- a/scripts/generate_errors.pl
+++ b/scripts/generate_errors.pl
@@ -68,9 +68,17 @@
close FILE;
my $found = 0;
while ($content =~ m[
- (?:/\*[*!]([^<](?:[^*]|\*+[^*/])*)\*/)?
- \s*\#\s*define\s+(MBEDTLS_ERR_\w+)\s+\-(0[Xx][0-9A-Fa-f]+)\s*
- (?:/\*[*!]<((?:[^*]|\*+[^*/])*)\*/)?
+ # Both the before-comment and the after-comment are optional.
+ # Only the comment content is a regex capture group. The comment
+ # start and end parts are outside the capture group.
+ (?:/\*[*!](?!<) # Doxygen before-comment start
+ ((?:[^*]|\*+[^*/])*) # $1: Comment content (no */ inside)
+ \*/)? # Comment end
+ \s*\#\s*define\s+(MBEDTLS_ERR_\w+) # $2: name
+ \s+\-(0[Xx][0-9A-Fa-f]+)\s* # $3: value (without the sign)
+ (?:/\*[*!]< # Doxygen after-comment start
+ ((?:[^*]|\*+[^*/])*) # $4: Comment content (no */ inside)
+ \*/)? # Comment end
]gsx) {
my ($before, $name, $value, $after) = ($1, $2, $3, $4);
# Discard Doxygen comments that are coincidentally present before
