Use preprocessor constants for environment variable names.

We broke the discipline Linus set up to allow compiler help us
avoid typos in environment names in the early days of git over
time.  This defines a handful preprocessor constants for
environment variable names used in relatively core parts of the
system.

I've left out variable names specific to subsystems such as HTTP
and SSL as I do not think they are big problems.

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/cache.h b/cache.h
index 8ad5920d2..4943056c1 100644
--- a/cache.h
+++ b/cache.h
@@ -122,6 +122,10 @@ extern int cache_errno;
 #define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 #define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 #define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
+#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
+#define CONFIG_ENVIRONMENT "GIT_CONFIG"
+#define CONFIG_LOCAL_ENVIRONMENT "GIT_CONFIG_LOCAL"
+#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 
 extern int is_bare_git_dir(const char *dir);
 extern const char *get_git_dir(void);