parse_config_key(): return subsection len as size_t

We return the length to a subset of a string using an "int *"
out-parameter. This is fine most of the time, as we'd expect config keys
to be relatively short, but it could behave oddly if we had a gigantic
config key. A more appropriate type is size_t.

Let's switch over, which lets our callers use size_t as appropriate
(they are bound by our type because they must pass the out-parameter as
a pointer). This is mostly just a cleanup to make it clear this code
handles long strings correctly. In practice, our config parser already
chokes on long key names (because of a similar int/size_t mixup!).

When doing an int/size_t conversion, we have to be careful that nobody
was trying to assign a negative value to the variable. I manually
confirmed that for each case here. They tend to just feed the result to
xmemdupz() or similar; in a few cases I adjusted the parameter types for
helper functions to make sure the size_t is preserved.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/submodule-config.c b/submodule-config.c
index 4d1c92d..e175dfb 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -225,7 +225,8 @@ static int name_and_item_from_var(const char *var, struct strbuf *name,
 				  struct strbuf *item)
 {
 	const char *subsection, *key;
-	int subsection_len, parse;
+	size_t subsection_len;
+	int parse;
 	parse = parse_config_key(var, "submodule", &subsection,
 			&subsection_len, &key);
 	if (parse < 0 || !subsection)