checkpatch: detect doubly-encoded UTF-8

Copy and pasting from Thunderbird's "view source" window results in double
encoding of multibyte UTF-8 sequences.  The appearance of those sequences is
very peculiar, so detect it and give an error despite the (low) possibility
of false positives.

As the major offender, I am also adding the same check to my applypatch-msg
and commit-msg hooks, but this will also cause patchew to croak loudly when
this mistake happens.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1558099140-53240-1-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2019-05-17 15:19:00 +02:00
parent 19752e09b4
commit 874acb6f83

View File

@ -262,6 +262,19 @@ our $UTF8 = qr{
| $NON_ASCII_UTF8
}x;
# some readers default to ISO-8859-1 when showing email source. detect
# when UTF-8 is incorrectly interpreted as ISO-8859-1 and reencoded back.
# False positives are possible but very unlikely.
our $UTF8_MOJIBAKE = qr{
\xC3[\x82-\x9F] \xC2[\x80-\xBF] # c2-df 80-bf
| \xC3\xA0 \xC2[\xA0-\xBF] \xC2[\x80-\xBF] # e0 a0-bf 80-bf
| \xC3[\xA1-\xAC\xAE\xAF] (?: \xC2[\x80-\xBF]){2} # e1-ec/ee/ef 80-bf 80-bf
| \xC3\xAD \xC2[\x80-\x9F] \xC2[\x80-\xBF] # ed 80-9f 80-bf
| \xC3\xB0 \xC2[\x90-\xBF] (?: \xC2[\x80-\xBF]){2} # f0 90-bf 80-bf 80-bf
| \xC3[\xB1-\xB3] (?: \xC2[\x80-\xBF]){3} # f1-f3 80-bf 80-bf 80-bf
| \xC3\xB4 \xC2[\x80-\x8F] (?: \xC2[\x80-\xBF]){2} # f4 80-b8 80-bf 80-bf
}x;
# There are still some false positives, but this catches most
# common cases.
our $typeTypedefs = qr{(?x:
@ -1506,6 +1519,9 @@ sub process {
ERROR("Invalid UTF-8, patch and commit message should be encoded in UTF-8\n" . $hereptr);
}
if ($rawline =~ m/$UTF8_MOJIBAKE/) {
ERROR("Doubly-encoded UTF-8\n" . $herecurr);
}
# Check if it's the start of a commit log
# (not a header line and we haven't seen the patch filename)
if ($in_header_lines && $realfile =~ /^$/ &&