lib: Extend LTP_ENABLE_DEBUG to support verbosity levels

Following the introduction of verbosity levels for the `-D` command line
flag, this patch extends the `LTP_ENABLE_DEBUG` environment variable to
support the same levels (1, and 2).

Previously, `LTP_ENABLE_DEBUG` acted as a simple boolean toggle. It now
mirrors the behavior of `-D`, allowing developers to specify the exact
level of debug verbosity required from the environment.

And, command-line should take precedence over environment variables when
set both.

Signed-off-by: Li Wang <liwang@redhat.com>
Reviewed-by: Andrea Cervesato <andrea.cervesato@suse.com>

Author: wangli5665

doc/developers/debugging.rst

@@ -9,7 +9,7 @@ Debug messages
 --------------
 
 The LTP framework supports ``TDEBUG`` flag test debug messages. These
-messages can be enabled using the ``-D`` parameter or setting ``LTP_ENABLE_DEBUG=1``
+messages can be enabled using the ``-D[1,2]`` parameter or setting ``LTP_ENABLE_DEBUG=1,2``
 environment variable (see :doc:`../users/setup_tests`).
 
 The ``-D`` parameter also supports the following verbosity levels:

lib/newlib_tests/tst_res_flags.c

@@ -21,7 +21,7 @@ static struct tcase {
 	{FLAG(TCONF)},
 	{FLAG(TWARN)},
 	{FLAG(TINFO)},
-	{FLAG(TDEBUG), " (printed only with -D or LTP_ENABLE_DEBUG=1)"},
+	{FLAG(TDEBUG), " (printed only with -D[1,2] or LTP_ENABLE_DEBUG=1,2)"},
 };
 
 static void do_cleanup(void)

lib/tst_test.c

@@ -675,7 +675,7 @@ static void print_help(void)
 	fprintf(stderr, "LTP_COLORIZE_OUTPUT      Force colorized output behaviour (y/1 always, n/0: never)\n");
 	fprintf(stderr, "LTP_DEV                  Path to the block device to be used (for .needs_device)\n");
 	fprintf(stderr, "LTP_DEV_FS_TYPE          Filesystem used for testing (default: %s)\n", DEFAULT_FS_TYPE);
-	fprintf(stderr, "LTP_ENABLE_DEBUG         Print debug messages (set 1 or y)\n");
+	fprintf(stderr, "LTP_ENABLE_DEBUG         Print debug messages (set 1(y) or 2)\n");
 	fprintf(stderr, "LTP_REPRODUCIBLE_OUTPUT  Values 1 or y discard the actual content of the messages printed by the test\n");
 	fprintf(stderr, "LTP_QUIET                Values 1 or y will suppress printing TCONF, TWARN, TINFO, and TDEBUG messages\n");
 	fprintf(stderr, "LTP_SINGLE_FS_TYPE       Specifies filesystem instead all supported (for .all_filesystems)\n");
@@ -1445,9 +1445,16 @@ static void do_setup(int argc, char *argv[])
 
 	parse_opts(argc, argv);
 
-	if (tdebug_env && (!strcmp(tdebug_env, "1") || !strcmp(tdebug_env, "y"))) {
-		tst_res(TINFO, "Enabling debug info");
-		context->tdebug = 1;
+	if (tdebug_env && !context->tdebug) {
+		if (!strcmp(tdebug_env, "2"))
+			context->tdebug = 2;
+		else if (!strcmp(tdebug_env, "1") || !strcmp(tdebug_env, "y"))
+			context->tdebug = 1;
+		else
+			tst_res(TWARN, "Invalid LTP_ENABLE_DEBUG value: %s", tdebug_env);
+
+		if (context->tdebug)
+			tst_res(TINFO, "Enabling debug info (level %d)", context->tdebug);
 	}
 
 	if (tst_test->needs_kconfigs && tst_kconfig_check(tst_test->needs_kconfigs))