git: fix numerous bugs in git_quote and git_unquote

git always quotes with leading zeros to ensure the octal
representation is 3 characters long.  We enforce that to match
low ASCII characters (e.g. [x01-\x06]) that don't need the
range provided by 3 characters.

git_unquote now does a single pass so it won't get fooled by
decoded backslashes into parsing a digit as an octal character.
git_unquote is also capped to "\377" so we don't overflow a
byte.

1 files changed, 2 insertions, 0 deletions

diff --git a/t/git.t b/t/git.t
index 4a45bbaf..bc1dea50 100644
--- a/t/git.t
+++ b/t/git.t
@@ -168,5 +168,7 @@ is(git_quote($s = "Eléanor"), '"El\\303\\251anor"', 'quoted octal');
 is(git_quote($s = "hello\"world"), '"hello\"world"', 'quoted dq');
 is(git_quote($s = "hello\\world"), '"hello\\\\world"', 'quoted backslash');
 is(git_quote($s = "hello\nworld"), '"hello\\nworld"', 'quoted LF');
+is(git_quote($s = "hello\x06world"), '"hello\\006world"', 'quoted \\x06');
+is(git_unquote($s = '"hello\\006world"'), "hello\x06world", 'unquoted \\x06');
 
 done_testing();