Merge branch 'jh/trace2-sid-fix'

Polishing of the new trace2 facility continues.  The system-level
configuration can specify site-wide trace2 settings, which can be
overridden with per-user configuration and environment variables.

* jh/trace2-sid-fix:
  trace2: fixup access problem on /etc/gitconfig in read_very_early_config
  trace2: update docs to describe system/global config settings
  trace2: make SIDs more unique
  trace2: clarify UTC datetime formatting
  trace2: report peak memory usage of the process
  trace2: use system/global config for default trace2 settings
  config: add read_very_early_config()
  trace2: find exec-dir before trace2 initialization
  trace2: add absolute elapsed time to start event
  trace2: refactor setting process starting time
  config: initialize opts structure in repo_read_config()

1 files changed, 16 insertions, 20 deletions

diff --git a/trace2/tr2_dst.c b/trace2/tr2_dst.c
index c3d82ca6a4..5dda0ca1cd 100644
--- a/trace2/tr2_dst.c
+++ b/trace2/tr2_dst.c
@@ -1,17 +1,7 @@
 #include "cache.h"
 #include "trace2/tr2_dst.h"
 #include "trace2/tr2_sid.h"
-
-/*
- * If a Trace2 target cannot be opened for writing, we should issue a
- * warning to stderr, but this is very annoying if the target is a pipe
- * or socket and beyond the user's control -- especially since every
- * git command (and sub-command) will print the message.  So we silently
- * eat these warnings and just discard the trace data.
- *
- * Enable the following environment variable to see these warnings.
- */
-#define TR2_ENVVAR_DST_DEBUG "GIT_TR2_DST_DEBUG"
+#include "trace2/tr2_sysenv.h"
 
 /*
  * How many attempts we will make at creating an automatically-named trace file.
@@ -23,7 +13,7 @@ static int tr2_dst_want_warning(void)
 	static int tr2env_dst_debug = -1;
 
 	if (tr2env_dst_debug == -1) {
-		const char *env_value = getenv(TR2_ENVVAR_DST_DEBUG);
+		const char *env_value = tr2_sysenv_get(TR2_SYSENV_DST_DEBUG);
 		if (!env_value || !*env_value)
 			tr2env_dst_debug = 0;
 		else
@@ -75,7 +65,8 @@ static int tr2_dst_try_auto_path(struct tr2_dst *dst, const char *tgt_prefix)
 		if (tr2_dst_want_warning())
 			warning("trace2: could not open '%.*s' for '%s' tracing: %s",
 				(int) base_path_len, path.buf,
-				dst->env_var_name, strerror(errno));
+				tr2_sysenv_display_name(dst->sysenv_var),
+				strerror(errno));
 
 		tr2_dst_trace_disable(dst);
 		strbuf_release(&path);
@@ -97,7 +88,9 @@ static int tr2_dst_try_path(struct tr2_dst *dst, const char *tgt_value)
 	if (fd == -1) {
 		if (tr2_dst_want_warning())
 			warning("trace2: could not open '%s' for '%s' tracing: %s",
-				tgt_value, dst->env_var_name, strerror(errno));
+				tgt_value,
+				tr2_sysenv_display_name(dst->sysenv_var),
+				strerror(errno));
 
 		tr2_dst_trace_disable(dst);
 		return 0;
@@ -171,7 +164,8 @@ static int tr2_dst_try_unix_domain_socket(struct tr2_dst *dst,
 	if (!path || !*path) {
 		if (tr2_dst_want_warning())
 			warning("trace2: invalid AF_UNIX value '%s' for '%s' tracing",
-				tgt_value, dst->env_var_name);
+				tgt_value,
+				tr2_sysenv_display_name(dst->sysenv_var));
 
 		tr2_dst_trace_disable(dst);
 		return 0;
@@ -181,7 +175,7 @@ static int tr2_dst_try_unix_domain_socket(struct tr2_dst *dst,
 	    strlen(path) >= sizeof(((struct sockaddr_un *)0)->sun_path)) {
 		if (tr2_dst_want_warning())
 			warning("trace2: invalid AF_UNIX path '%s' for '%s' tracing",
-				path, dst->env_var_name);
+				path, tr2_sysenv_display_name(dst->sysenv_var));
 
 		tr2_dst_trace_disable(dst);
 		return 0;
@@ -203,7 +197,8 @@ static int tr2_dst_try_unix_domain_socket(struct tr2_dst *dst,
 error:
 	if (tr2_dst_want_warning())
 		warning("trace2: could not connect to socket '%s' for '%s' tracing: %s",
-			path, dst->env_var_name, strerror(e));
+			path, tr2_sysenv_display_name(dst->sysenv_var),
+			strerror(e));
 
 	tr2_dst_trace_disable(dst);
 	return 0;
@@ -223,7 +218,7 @@ static void tr2_dst_malformed_warning(struct tr2_dst *dst,
 	struct strbuf buf = STRBUF_INIT;
 
 	strbuf_addf(&buf, "trace2: unknown value for '%s': '%s'",
-		    dst->env_var_name, tgt_value);
+		    tr2_sysenv_display_name(dst->sysenv_var), tgt_value);
 	warning("%s", buf.buf);
 
 	strbuf_release(&buf);
@@ -239,7 +234,7 @@ int tr2_dst_get_trace_fd(struct tr2_dst *dst)
 
 	dst->initialized = 1;
 
-	tgt_value = getenv(dst->env_var_name);
+	tgt_value = tr2_sysenv_get(dst->sysenv_var);
 
 	if (!tgt_value || !strcmp(tgt_value, "") || !strcmp(tgt_value, "0") ||
 	    !strcasecmp(tgt_value, "false")) {
@@ -305,7 +300,8 @@ void tr2_dst_write_line(struct tr2_dst *dst, struct strbuf *buf_line)
 		return;
 
 	if (tr2_dst_want_warning())
-		warning("unable to write trace to '%s': %s", dst->env_var_name,
+		warning("unable to write trace to '%s': %s",
+			tr2_sysenv_display_name(dst->sysenv_var),
 			strerror(errno));
 	tr2_dst_trace_disable(dst);
 }