From 2a10de3b3b5a198a1633ff4167a9610c493994c1 Mon Sep 17 00:00:00 2001
From: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Date: Tue, 22 May 2018 13:48:07 -0400
Subject: [PATCH 1/1] Introduce LTTNG_RELAYD_WORKING_DIRECTORY environment
 variable
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LTTNG_RELAYD_WORKING_DIRECTORY is equivalent to the --working-directory
command line options.

Note: when using --working-directory, the command line option always
overwrite the environment configuration, LTTNG_RELAYD_WORKING_DIRECTORY
in this case.

Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---
 src/bin/lttng-relayd/main.c                   | 29 +++++++++-
 src/common/defaults.h                         |  2 +
 .../test_relayd_working_directory             | 57 ++++++++++++++++++-
 3 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index ad97a0b9b..5f72c32a9 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -406,6 +406,23 @@ end:
 	return ret;
 }
 
+static int parse_env_options(void)
+{
+	int ret = 0;
+	char *value = NULL;
+
+	value = lttng_secure_getenv(DEFAULT_LTTNG_RELAYD_WORKING_DIRECTORY_ENV);
+	if (value) {
+		opt_working_directory = strdup(value);
+		if (!opt_working_directory) {
+			ERR("Failed to allocate working directory string (\"%s\")",
+					value);
+			ret = -1;
+		}
+	}
+	return ret;
+}
+
 static int set_options(int argc, char **argv)
 {
 	int c, ret = 0, option_index = 0, retval = 0;
@@ -3686,7 +3703,17 @@ int main(int argc, char **argv)
 	int ret = 0, retval = 0;
 	void *status;
 
-	/* Parse arguments */
+	/* Parse environment variables */
+	ret = parse_env_options();
+	if (ret) {
+		retval = -1;
+		goto exit_options;
+	}
+
+	/*
+	 * Parse arguments.
+	 * Command line arguments overwrite environment.
+	 */
 	progname = argv[0];
 	if (set_options(argc, argv)) {
 		retval = -1;
diff --git a/src/common/defaults.h b/src/common/defaults.h
index 183e31518..1545d0a74 100644
--- a/src/common/defaults.h
+++ b/src/common/defaults.h
@@ -346,6 +346,8 @@
 #define DEFAULT_LTTNG_RELAYD_TCP_KEEP_ALIVE_PROBE_INTERVAL_ENV "LTTNG_RELAYD_TCP_KEEP_ALIVE_PROBE_INTERVAL"
 #define DEFAULT_LTTNG_RELAYD_TCP_KEEP_ALIVE_ABORT_THRESHOLD_ENV "LTTNG_RELAYD_TCP_KEEP_ALIVE_ABORT_THRESHOLD"
 
+#define DEFAULT_LTTNG_RELAYD_WORKING_DIRECTORY_ENV "LTTNG_RELAYD_WORKING_DIRECTORY"
+
 /*
  * Name of the intermediate directory used to rename the trace chunk of a
  * session's first rotation.
diff --git a/tests/regression/tools/working-directory/test_relayd_working_directory b/tests/regression/tools/working-directory/test_relayd_working_directory
index 13e816d8a..8a261af21 100755
--- a/tests/regression/tools/working-directory/test_relayd_working_directory
+++ b/tests/regression/tools/working-directory/test_relayd_working_directory
@@ -22,11 +22,10 @@ TESTDIR=$CURDIR/../../../
 
 DIR=$(readlink -f "$TESTDIR")
 
-NUM_TESTS=27
+NUM_TESTS=35
 
 source $TESTDIR/utils/utils.sh
 
-
 #MUST set TESTDIR before calling those functions
 plan_tests $NUM_TESTS
 
@@ -223,6 +222,58 @@ function test_relayd_failure()
 	rm -rf "$working_dir"
 }
 
+function test_relayd_env()
+{
+	local working_dir
+	local cwd
+	local pid
+
+	working_dir=$(mktemp -d)
+
+	diag "Test lttng-relayd change working directory from env. variable"
+
+	export LTTNG_RELAYD_WORKING_DIRECTORY=${working_dir}
+	start_lttng_relayd_opt 1 "-b" ""
+
+	pid=$(pgrep "$RELAYD_MATCH")
+	ok $? "Found lttng-relayd"
+
+	cwd=$(readlink "/proc/$pid/cwd")
+
+	is "$cwd" "$working_dir" "Working directory changed"
+
+	stop_lttng_relayd
+	rm -rf "$working_dir"
+	unset LTTNG_RELAYD_WORKING_DIRECTORY
+}
+
+function test_relayd_cmdline_overwrite_env()
+{
+	local working_dir_env
+	local working_dir_cmdline
+	local cwd
+	local pid
+
+	working_dir_env=$(mktemp -d)
+	working_dir_cmdline=$(mktemp -d)
+
+	diag "Test lttng-relayd change working directory command line overwrite env variable"
+
+	export LTTNG_RELAYD_WORKING_DIRECTORY=${working_dir_env}
+	start_lttng_relayd_opt 1 "-b" "--working-dir ${working_dir_cmdline}"
+
+	pid=$(pgrep "$RELAYD_MATCH")
+	ok $? "Found lttng-relayd"
+
+	cwd=$(readlink "/proc/$pid/cwd")
+
+	is "$cwd" "$working_dir_cmdline" "Working directory is the one from command line"
+
+	stop_lttng_relayd
+	rm -rf "$working_dir_env" "$working_dir_cmdline"
+	unset LTTNG_RELAYD_WORKING_DIRECTORY
+}
+
 TESTS=(
 	test_relayd
 	test_relayd_daemon
@@ -231,6 +282,8 @@ TESTS=(
 	test_relayd_background_no_working_dir
 	test_relayd_debug_permission
 	test_relayd_failure
+	test_relayd_env
+	test_relayd_cmdline_overwrite_env
 )
 
 for fct_test in "${TESTS[@]}";
-- 
2.34.1