setup: make read_early_config() reusable

The pager configuration needs to be read early, possibly before
discovering any .git/ directory.

Let's not hide this function in pager.c, but make it available to other
callers.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/config.c b/config.c
index c6b874a..9cfbeaf 100644
--- a/config.c
+++ b/config.c
@@ -1412,6 +1412,37 @@ static void configset_iter(struct config_set *cs, config_fn_t fn, void *data)
 	}
 }
 
+void read_early_config(config_fn_t cb, void *data)
+{
+	git_config_with_options(cb, data, NULL, 1);
+
+	/*
+	 * Note that this is a really dirty hack that does the wrong thing in
+	 * many cases. The crux of the problem is that we cannot run
+	 * setup_git_directory() early on in git's setup, so we have no idea if
+	 * we are in a repository or not, and therefore are not sure whether
+	 * and how to read repository-local config.
+	 *
+	 * So if we _aren't_ in a repository (or we are but we would reject its
+	 * core.repositoryformatversion), we'll read whatever is in .git/config
+	 * blindly. Similarly, if we _are_ in a repository, but not at the
+	 * root, we'll fail to find .git/config (because it's really
+	 * ../.git/config, etc). See t7006 for a complete set of failures.
+	 *
+	 * However, we have historically provided this hack because it does
+	 * work some of the time (namely when you are at the top-level of a
+	 * valid repository), and would rarely make things worse (i.e., you do
+	 * not generally have a .git/config file sitting around).
+	 */
+	if (!startup_info->have_repository) {
+		struct git_config_source repo_config;
+
+		memset(&repo_config, 0, sizeof(repo_config));
+		repo_config.file = ".git/config";
+		git_config_with_options(cb, data, &repo_config, 1);
+	}
+}
+
 static void git_config_check_init(void);
 
 void git_config(config_fn_t fn, void *data)