convert: refactor code to clarify ownership of check_roundtrip_encoding

The `check_roundtrip_encoding` variable is tracked in a `const char *`
even though it may contain allocated strings at times. The result is
that those strings may be leaking because we never free them.

Refactor the code to always store allocated strings in this variable.
The default value is handled in `check_roundtrip()` now, which is the
only user of the variable.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/config.c b/config.c
index fb56e11276..f9101045ee 100644
--- a/config.c
+++ b/config.c
@@ -1564,8 +1564,10 @@ static int git_default_core_config(const char *var, const char *value,
 		return 0;
 	}
 
-	if (!strcmp(var, "core.checkroundtripencoding"))
-		return git_config_string(&check_roundtrip_encoding, var, value);
+	if (!strcmp(var, "core.checkroundtripencoding")) {
+		FREE_AND_NULL(check_roundtrip_encoding);
+		return git_config_string((const char **) &check_roundtrip_encoding, var, value);
+	}
 
 	if (!strcmp(var, "core.notesref")) {
 		if (!value)