trace2: teach Git to log environment variables

Via trace2, Git can already log interesting config parameters (see the
trace2_cmd_list_config() function). However, this can grant an
incomplete picture because many config parameters also allow overrides
via environment variables.

To allow for more complete logs, we add a new trace2_cmd_list_env_vars()
function and supporting implementation, modeled after the pre-existing
config param logging implementation.

Signed-off-by: Josh Steadmon <steadmon@google.com>
Acked-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/trace2.c b/trace2.c
index c7b4f14d29..2c6b570077 100644
--- a/trace2.c
+++ b/trace2.c
@@ -121,6 +121,7 @@ static void tr2main_atexit_handler(void)
 	tr2_sid_release();
 	tr2_cmd_name_release();
 	tr2_cfg_free_patterns();
+	tr2_cfg_free_env_vars();
 	tr2_sysenv_release();
 
 	trace2_enabled = 0;
@@ -311,6 +312,14 @@ void trace2_cmd_list_config_fl(const char *file, int line)
 	tr2_cfg_list_config_fl(file, line);
 }
 
+void trace2_cmd_list_env_vars_fl(const char *file, int line)
+{
+	if (!trace2_enabled)
+		return;
+
+	tr2_list_env_vars_fl(file, line);
+}
+
 void trace2_cmd_set_config_fl(const char *file, int line, const char *key,
 			      const char *value)
 {