[PATCH 5/9] builtin: introduce startup_info struct

[Jonathan Nieder <jrnieder@gmail.com>]

From: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>

The startup_info struct will collect information managed by the git
setup code, such as the prefix for relative paths passed on the
command line (i.e., path to the starting cwd from the toplevel of
the work tree) and whether a git repository has been found.

In other words, startup_info is intended to be a collection of global
variables representing results that were previously returned from
setup functions.  Letting these values persist means there is more
flexibility in deciding when to run setup.

For now, the struct is empty.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
Creation of struct split off from its population, mostly for
reviewability.  Feel free to merge this patch with the next one
if you prefer.

 cache.h       |    5 +++++
 environment.c |    1 +
 git.c         |    4 ++++
 3 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/cache.h b/cache.h
index 5eb0573..1479824 100644
--- a/cache.h
+++ b/cache.h
@@ -1058,6 +1058,11 @@ void overlay_tree_on_cache(const char *tree_name, const char *prefix);
 char *alias_lookup(const char *alias);
 int split_cmdline(char *cmdline, const char ***argv);
 
+/* git.c */
+struct startup_info {
+};
+extern struct startup_info *startup_info;
+
 /* builtin/merge.c */
 int checkout_fast_forward(const unsigned char *from, const unsigned char *to);
 
diff --git a/environment.c b/environment.c
index 876c5e5..c36c902 100644
--- a/environment.c
+++ b/environment.c
@@ -52,6 +52,7 @@ enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE;
 char *notes_ref_name;
 int grafts_replace_parents = 1;
 int core_apply_sparse_checkout;
+struct startup_info *startup_info;
 
 /* Parallel index stat data preload? */
 int core_preload_index = 0;
diff --git a/git.c b/git.c
index 32720e5..b1d51c9 100644
--- a/git.c
+++ b/git.c
@@ -13,6 +13,7 @@ const char git_usage_string[] =
 const char git_more_info_string[] =
 	"See 'git help COMMAND' for more information on a specific command.";
 
+static struct startup_info git_startup_info;
 static int use_pager = -1;
 struct pager_config {
 	const char *cmd;
@@ -477,6 +478,9 @@ int main(int argc, const char **argv)
 {
 	const char *cmd;
 
+	memset(&git_startup_info, 0, sizeof(git_startup_info));
+	startup_info = &git_startup_info;
+
 	cmd = git_extract_argv0_path(argv[0]);
 	if (!cmd)
 		cmd = "git-help";
-- 
1.7.0.4