On 7/3/20 4:59 AM, Jesper Dangaard Brouer wrote:
On Thu, 2 Jul 2020 14:24:14 -0700
Yonghong Song <yhs@xxxxxx> wrote:
On 7/2/20 10:59 AM, Jesper Dangaard Brouer wrote:
This is a follow up adjustment to commit 6c92bd5cd465 ("selftests/bpf:
Test_progs indicate to shell on non-actions"), that returns shell exit
indication EXIT_FAILURE (value 1) when user selects a non-existing test.
The problem with using EXIT_FAILURE is that a shell script cannot tell
the difference between a non-existing test and the test failing.
This patch uses value 2 as shell exit indication.
(Aside note unrecognized option parameters use value 64).
Fixes: 6c92bd5cd465 ("selftests/bpf: Test_progs indicate to shell on non-actions")
Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
---
tools/testing/selftests/bpf/test_progs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index 104e833d0087..e8f7cd5dbae4 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -12,6 +12,8 @@
#include <string.h>
#include <execinfo.h> /* backtrace */
+#define EXIT_NO_TEST 2
How do you ensure this won't collide with other exit code
from other library functions (e.g., error code 64 is used
for unrecognized option which I have no idea what 64 means)?
I expect 64 comes from: /usr/include/sysexits.h
#define EX_USAGE 64 /* command line usage error */
Thanks for the pointer.
Maybe -2 for the exit code?
No. The process's exit status must be a number between 0 and 255, as
defined in man exit(3). (run: 'man 3 exit' as there are many manpages
named exit).
Yes, if user app exits with -2, it actually prints 254, -1 for 255...
But don't use above 127, because that is usually used for indicating
signals. E.g. 139 means 11=SIGSEGV $((139 & 127))=11. POSIX defines
in man wait(3p) check WIFSIGNALED(STATUS) and WTERMSIG(139)=11.
(Hint: cmd 'kill -l' list signals and their numbers).
I bring up Segmentation fault explicitly, as we are seeing these happen
with different tests (that are part of test_progs). CI people writing
these shell-scripts could pickup these hints and report them, if that
makes sense.
Make sense to use from 1 - 127 range for normal exit.
test_progs already uses -1.
Well that is a bug then. This will be seen by the shell (parent
process) as 255.
I think previously people may just check test_progs return 0 or non-0.
Since here you will try to check different error return code, It makes
sense to do an audit to explicitly define all return values. So this
way, tools can have a reliable way to check exit code.
+
/* defined in test_progs.h */
struct test_env env = {};
@@ -740,7 +742,7 @@ int main(int argc, char **argv)
close(env.saved_netns_fd);
if (env.succ_cnt + env.fail_cnt + env.skip_cnt == 0)
- return EXIT_FAILURE;
+ return EXIT_NO_TEST;
return env.fail_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
}
