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@xxxxxxxxxx>
---
As I mentioned in the commit message, I modeled this pretty closely on
the config parameter reporting code. It may make sense to split some of
this out into its own file, particularly the parts in trace2/tr2_cfg.c.
Alternatively, we could also just make the env var reporting part of the
config param reporting. Let me know if you have a preference either way.
Documentation/config/trace2.txt | 9 ++++
Documentation/technical/api-trace2.txt | 3 +-
git.c | 3 ++
t/helper/test-tool.c | 1 +
t/t0212-trace2-event.sh | 37 ++++++++++++++++
trace2.c | 9 ++++
trace2.h | 13 ++++++
trace2/tr2_cfg.c | 58 ++++++++++++++++++++++++++
trace2/tr2_cfg.h | 8 ++++
trace2/tr2_sysenv.c | 2 +
trace2/tr2_sysenv.h | 1 +
11 files changed, 143 insertions(+), 1 deletion(-)
diff --git a/Documentation/config/trace2.txt b/Documentation/config/trace2.txt
index 4ce0b9a6d1..01d3afd8a8 100644
--- a/Documentation/config/trace2.txt
+++ b/Documentation/config/trace2.txt
@@ -48,6 +48,15 @@ trace2.configParams::
May be overridden by the `GIT_TRACE2_CONFIG_PARAMS` environment
variable. Unset by default.
+trace2.envVars::
+ A comma-separated list of "important" environment variables that should
+ be recorded in the trace2 output. For example,
+ `GIT_HTTP_USER_AGENT,GIT_CONFIG` would cause the trace2 output to
+ contain events listing the overrides for HTTP user agent and the
+ location of the Git configuration file (assuming any are set). May be
+ overriden by the `GIT_TRACE2_ENV_VARS` environment variable. Unset by
+ default.
+
trace2.destinationDebug::
Boolean. When true Git will print error messages when a
trace target destination cannot be opened for writing.
diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt
index 4f07ceadcb..6b6085585d 100644
--- a/Documentation/technical/api-trace2.txt
+++ b/Documentation/technical/api-trace2.txt
@@ -656,7 +656,8 @@ The "exec_id" field is a command-unique id and is only useful if the
------------
`"def_param"`::
- This event is generated to log a global parameter.
+ This event is generated to log a global parameter, such as a config
+ setting, command-line flag, or environment variable.
+
------------
{
diff --git a/git.c b/git.c
index 7be7ad34bd..b7dbe82b0d 100644
--- a/git.c
+++ b/git.c
@@ -351,6 +351,7 @@ static int handle_alias(int *argcp, const char ***argv)
trace2_cmd_alias(alias_command, child.args.argv);
trace2_cmd_list_config();
+ trace2_cmd_list_env_vars();
trace2_cmd_name("_run_shell_alias_");
ret = run_command(&child);
@@ -388,6 +389,7 @@ static int handle_alias(int *argcp, const char ***argv)
trace2_cmd_alias(alias_command, new_argv);
trace2_cmd_list_config();
+ trace2_cmd_list_env_vars();
*argv = new_argv;
*argcp += count - 1;
@@ -439,6 +441,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
trace_argv_printf(argv, "trace: built-in: git");
trace2_cmd_name(p->cmd);
trace2_cmd_list_config();
+ trace2_cmd_list_env_vars();
validate_cache_entries(the_repository->index);
status = p->fn(argc, argv, prefix);
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index c9a232d238..4cdab7eef2 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -111,6 +111,7 @@ int cmd_main(int argc, const char **argv)
argc--;
trace2_cmd_name(cmds[i].name);
trace2_cmd_list_config();
+ trace2_cmd_list_env_vars();
return cmds[i].fn(argc, argv);
}
}
diff --git a/t/t0212-trace2-event.sh b/t/t0212-trace2-event.sh
index 7065a1b937..1529155cf0 100755
--- a/t/t0212-trace2-event.sh
+++ b/t/t0212-trace2-event.sh
@@ -199,6 +199,43 @@ test_expect_success JSON_PP 'event stream, list config' '
test_cmp expect actual
'
+# Test listing of all "interesting" environment variables.
+
+test_expect_success JSON_PP 'event stream, list env vars' '
+ test_when_finished "rm trace.event actual expect" &&
+ GIT_TRACE2_EVENT="$(pwd)/trace.event" \
+ GIT_TRACE2_ENV_VARS="A_VAR,OTHER_VAR,MISSING" \
+ A_VAR=1 OTHER_VAR="hello world" test-tool trace2 001return 0 &&
+ perl "$TEST_DIRECTORY/t0212/parse_events.perl" <trace.event >actual &&
+ sed -e "s/^|//" >expect <<-EOF &&
+ |VAR1 = {
+ | "_SID0_":{
+ | "argv":[
+ | "_EXE_",
+ | "trace2",
+ | "001return",
+ | "0"
+ | ],
+ | "exit_code":0,
+ | "hierarchy":"trace2",
+ | "name":"trace2",
+ | "params":[
+ | {
+ | "param":"A_VAR",
+ | "value":"1"
+ | },
+ | {
+ | "param":"OTHER_VAR",
+ | "value":"hello world"
+ | }
+ | ],
+ | "version":"$V"
+ | }
+ |};
+ EOF
+ test_cmp expect actual
+'
+
test_expect_success JSON_PP 'basic trace2_data' '
test_when_finished "rm trace.event actual expect" &&
GIT_TRACE2_EVENT="$(pwd)/trace.event" test-tool trace2 006data test_category k1 v1 test_category k2 v2 &&
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)
{
diff --git a/trace2.h b/trace2.h
index e5e81c0533..b18bc5529c 100644
--- a/trace2.h
+++ b/trace2.h
@@ -182,6 +182,19 @@ void trace2_cmd_list_config_fl(const char *file, int line);
#define trace2_cmd_list_config() trace2_cmd_list_config_fl(__FILE__, __LINE__)
+/*
+ * Emit one or more 'def_param' events for "important" environment variables.
+ *
+ * Use the TR2_SYSENV_ENV_VARS setting to register a comma-separated list of
+ * environment variables considered important. For example:
+ * git config --system trace2.envVars 'GIT_HTTP_USER_AGENT,GIT_CONFIG'
+ * or:
+ * GIT_TRACE2_ENV_VARS="GIT_HTTP_USER_AGENT,GIT_CONFIG"
+ */
+void trace2_cmd_list_env_vars_fl(const char *file, int line);
+
+#define trace2_cmd_list_env_vars() trace2_cmd_list_env_vars_fl(__FILE__, __LINE__)
+
/*
* Emit a "def_param" event for the given config key/value pair IF
* we consider the key to be "important".
diff --git a/trace2/tr2_cfg.c b/trace2/tr2_cfg.c
index caa7f06948..ec9ac1a6ef 100644
--- a/trace2/tr2_cfg.c
+++ b/trace2/tr2_cfg.c
@@ -7,6 +7,10 @@ static struct strbuf **tr2_cfg_patterns;
static int tr2_cfg_count_patterns;
static int tr2_cfg_loaded;
+static struct strbuf **tr2_cfg_env_vars;
+static int tr2_cfg_env_vars_count;
+static int tr2_cfg_env_vars_loaded;
+
/*
* Parse a string containing a comma-delimited list of config keys
* or wildcard patterns into a list of strbufs.
@@ -46,6 +50,45 @@ void tr2_cfg_free_patterns(void)
tr2_cfg_loaded = 0;
}
+/*
+ * Parse a string containing a comma-delimited list of environment variable
+ * names into a list of strbufs.
+ */
+static int tr2_load_env_vars(void)
+{
+ struct strbuf **s;
+ const char *varlist;
+
+ if (tr2_cfg_env_vars_loaded)
+ return tr2_cfg_env_vars_count;
+ tr2_cfg_env_vars_loaded = 1;
+
+ varlist = tr2_sysenv_get(TR2_SYSENV_ENV_VARS);
+ if (!varlist || !*varlist)
+ return tr2_cfg_env_vars_count;
+
+ tr2_cfg_env_vars = strbuf_split_buf(varlist, strlen(varlist), ',', -1);
+ for (s = tr2_cfg_env_vars; *s; s++) {
+ struct strbuf *buf = *s;
+
+ if (buf->len && buf->buf[buf->len - 1] == ',')
+ strbuf_setlen(buf, buf->len - 1);
+ strbuf_trim_trailing_newline(*s);
+ strbuf_trim(*s);
+ }
+
+ tr2_cfg_env_vars_count = s - tr2_cfg_env_vars;
+ return tr2_cfg_env_vars_count;
+}
+
+void tr2_cfg_free_env_vars(void)
+{
+ if (tr2_cfg_env_vars)
+ strbuf_list_free(tr2_cfg_env_vars);
+ tr2_cfg_env_vars_count = 0;
+ tr2_cfg_env_vars_loaded = 0;
+}
+
struct tr2_cfg_data {
const char *file;
int line;
@@ -79,6 +122,21 @@ void tr2_cfg_list_config_fl(const char *file, int line)
read_early_config(tr2_cfg_cb, &data);
}
+void tr2_list_env_vars_fl(const char *file, int line)
+{
+ struct strbuf **s;
+
+ if (tr2_load_env_vars() <= 0)
+ return;
+
+ for (s = tr2_cfg_env_vars; *s; s++) {
+ struct strbuf *buf = *s;
+ const char *val = getenv(buf->buf);
+ if (val && *val)
+ trace2_def_param_fl(file, line, buf->buf, val);
+ }
+}
+
void tr2_cfg_set_fl(const char *file, int line, const char *key,
const char *value)
{
diff --git a/trace2/tr2_cfg.h b/trace2/tr2_cfg.h
index d9c98f64dd..a11d71feb5 100644
--- a/trace2/tr2_cfg.h
+++ b/trace2/tr2_cfg.h
@@ -7,6 +7,12 @@
*/
void tr2_cfg_list_config_fl(const char *file, int line);
+/*
+ * Iterate over all "interesting" environment variables and emit 'def_param'
+ * events for them to TRACE2.
+ */
+void tr2_list_env_vars_fl(const char *file, int line);
+
/*
* Emit a "def_param" event for the given key/value pair IF we consider
* the key to be "interesting".
@@ -16,4 +22,6 @@ void tr2_cfg_set_fl(const char *file, int line, const char *key,
void tr2_cfg_free_patterns(void);
+void tr2_cfg_free_env_vars(void);
+
#endif /* TR2_CFG_H */
diff --git a/trace2/tr2_sysenv.c b/trace2/tr2_sysenv.c
index 3c3792eca2..a380dcf910 100644
--- a/trace2/tr2_sysenv.c
+++ b/trace2/tr2_sysenv.c
@@ -29,6 +29,8 @@ struct tr2_sysenv_entry {
static struct tr2_sysenv_entry tr2_sysenv_settings[] = {
[TR2_SYSENV_CFG_PARAM] = { "GIT_TRACE2_CONFIG_PARAMS",
"trace2.configparams" },
+ [TR2_SYSENV_ENV_VARS] = { "GIT_TRACE2_ENV_VARS",
+ "trace2.envvars" },
[TR2_SYSENV_DST_DEBUG] = { "GIT_TRACE2_DST_DEBUG",
"trace2.destinationdebug" },
diff --git a/trace2/tr2_sysenv.h b/trace2/tr2_sysenv.h
index d4364a7b85..3292ee15bc 100644
--- a/trace2/tr2_sysenv.h
+++ b/trace2/tr2_sysenv.h
@@ -11,6 +11,7 @@
*/
enum tr2_sysenv_variable {
TR2_SYSENV_CFG_PARAM = 0,
+ TR2_SYSENV_ENV_VARS,
TR2_SYSENV_DST_DEBUG,
--
2.25.1.696.g5e7596f4ac-goog
