lazily load core.sharedrepository

The "shared_repository" config is loaded as part of
check_repository_format_version, but it's not quite like the
other values we check there. Something like
core.repositoryformatversion only makes sense in per-repo
config, but core.sharedrepository can be set in a per-user
config (e.g., to make all "git init" invocations shared by
default).

So it would make more sense as part of git_default_config.
Commit 457f06d (Introduce core.sharedrepository, 2005-12-22)
says:

  [...]the config variable is set in the function which
  checks the repository format. If this were done in
  git_default_config instead, a lot of programs would need
  to be modified to call git_config(git_default_config)
  first.

This is still the case today, but we have one extra trick up
our sleeve. Now that we have the git_configset
infrastructure, it's not so expensive for us to ask for a
single value. So we can simply lazy-load it on demand.

This should be OK to do in general. There are some problems
with loading config before setup_git_directory() is called,
but we shouldn't be accessing the value before then (if we
were, then it would already be broken, as the variable would
not have been set by check_repository_format_version!). The
trickiest caller is git-init, but it handles the values
manually itself.

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

1 files changed, 9 insertions, 0 deletions

diff --git a/environment.c b/environment.c
index b42e238434..8b8c8e8496 100644
--- a/environment.c
+++ b/environment.c
@@ -326,13 +326,22 @@ const char *get_commit_output_encoding(void)
 }
 
 static int the_shared_repository = PERM_UMASK;
+static int need_shared_repository_from_config = 1;
 
 void set_shared_repository(int value)
 {
 	the_shared_repository = value;
+	need_shared_repository_from_config = 0;
 }
 
 int get_shared_repository(void)
 {
+	if (need_shared_repository_from_config) {
+		const char *var = "core.sharedrepository";
+		const char *value;
+		if (!git_config_get_value(var, &value))
+			the_shared_repository = git_config_perm(var, value);
+		need_shared_repository_from_config = 0;
+	}
 	return the_shared_repository;
 }