From c7cc870e07722a234c620f87edbed55354fb3009 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] Backport: Introduce LTTNG_RELAYD_WORKING_DIRECTORY
 environment variable

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>
---
 src/bin/lttng-relayd/main.c                   | 18 +++++++-
 src/common/defaults.h                         |  2 +
 .../test_relayd_workding_directory            | 41 ++++++++++++++++++-
 3 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index 7f0b413bc..c171dfdfe 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -374,6 +374,16 @@ end:
 	return ret;
 }
 
+static void parse_env_options(void)
+{
+	char *value = NULL;
+
+	value = lttng_secure_getenv(DEFAULT_LTTNG_RELAYD_WORKING_DIRECTORY_ENV);
+	if (value) {
+		opt_working_directory = value;
+	}
+}
+
 static int set_options(int argc, char **argv)
 {
 	int c, ret = 0, option_index = 0, retval = 0;
@@ -3156,7 +3166,13 @@ int main(int argc, char **argv)
 	int ret = 0, retval = 0;
 	void *status;
 
-	/* Parse arguments */
+	/* Parse environment variables */
+	parse_env_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 d88d7b1a6..efe7f3058 100644
--- a/src/common/defaults.h
+++ b/src/common/defaults.h
@@ -323,6 +323,8 @@
 #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"
+
 /*
  * Returns the default subbuf size.
  *
diff --git a/tests/regression/tools/working-directory/test_relayd_workding_directory b/tests/regression/tools/working-directory/test_relayd_workding_directory
index 2422ea8c0..bf486893f 100755
--- a/tests/regression/tools/working-directory/test_relayd_workding_directory
+++ b/tests/regression/tools/working-directory/test_relayd_workding_directory
@@ -22,11 +22,10 @@ TESTDIR=$CURDIR/../../../
 
 DIR=$(readlink -f $TESTDIR)
 
-NUM_TESTS=22
+NUM_TESTS=28
 
 source $TESTDIR/utils/utils.sh
 
-
 #MUST set TESTDIR before calling those functions
 plan_tests $NUM_TESTS
 
@@ -181,6 +180,42 @@ function test_relayd_failure()
 	rm -rf ${working_dir} ${output_dest}
 }
 
+function test_relayd_env()
+{
+	local 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" ""
+
+	local cwd=$(readlink /proc/${RELAYD_PIDS}/cwd)
+
+	is "x${cwd}" "x${working_dir}" "Working directory changed"
+
+	stop_lttng_relayd
+	rm -rf ${working_dir}
+	unset LTTNG_RELAYD_WORKING_DIRECTORY
+}
+
+function test_relayd_cmdline_overwrite_env()
+{
+	local working_dir_env=$(mktemp -d)
+	local 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 ${working_dir_cmdline}"
+
+	local cwd=$(readlink /proc/${RELAYD_PIDS}/cwd)
+
+	is "x${cwd}" "x${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
@@ -189,6 +224,8 @@ 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