[PATCH 2/7] setup: handle NULL value when parsing extensions

From: Jeff King <peff@peff.net>
Date: Dec 7, 2023, 07:11 UTC
Message-ID: <20231207071121.GB1276005@coredump.intra.peff.net>
In-Reply-To: <20231207071030.GA1275835@coredump.intra.peff.net>

The "partialclone" extension config records a string, and hence it is an error to have an implicit bool like:

  [extensions]
  partialclone

in your config. We should recognize and reject this, rather than segfaulting (which is the current behavior). Note that it's OK to use config_error_nonbool() here, even though the return value is an enum. We explicitly document EXTENSION_ERROR as -1 for compatibility with error(), etc.

This is the only extension value that has this problem. Most of the others are bools that interpret this value naturally. The exception is extensions.objectformat, which does correctly check for NULL.

Signed-off-by: Jeff King <peff@peff.net>
---
 setup.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/setup.c b/setup.c
index fc592dc6dd..50131be7cc 100644
--- a/setup.c
+++ b/setup.c
@@ -559,6 +559,8 @@ static enum extension_result handle_extension_v0(const char *var,
 			data->precious_objects = git_config_bool(var, value);
 			return EXTENSION_OK;
 		} else if (!strcmp(ext, "partialclone")) {
+			if (!value)
+				return config_error_nonbool(var);
 			data->partial_clone = xstrdup(value);
 			return EXTENSION_OK;
 		} else if (!strcmp(ext, "worktreeconfig")) {

-- 
2.43.0.664.ga12c899002