diff options
author | Eduard Zingerman | 2024-03-06 12:45:19 +0200 |
---|---|---|
committer | Andrii Nakryiko | 2024-03-06 15:18:15 -0800 |
commit | c8617e8bcf8d1ef357fadf5c96bd86b9952fb93f (patch) | |
tree | 98d73393511d70d2f7712f98ae0ace043330d0bc /tools | |
parent | 5bab7a277ca8d4ef377a50a6678577b5bd7f74d8 (diff) |
selftests/bpf: Utility functions to capture libbpf log in test_progs
Several test_progs tests already capture libbpf log in order to check
for some expected output, e.g bpf_tcp_ca.c, kfunc_dynptr_param.c,
log_buf.c and a few others.
This commit provides a, hopefully, simple API to capture libbpf log
w/o necessity to define new print callback in each test:
/* Creates a global memstream capturing INFO and WARN level output
* passed to libbpf_print_fn.
* Returns 0 on success, negative value on failure.
* On failure the description is printed using PRINT_FAIL and
* current test case is marked as fail.
*/
int start_libbpf_log_capture(void)
/* Destroys global memstream created by start_libbpf_log_capture().
* Returns a pointer to captured data which has to be freed.
* Returned buffer is null terminated.
*/
char *stop_libbpf_log_capture(void)
The intended usage is as follows:
if (start_libbpf_log_capture())
return;
use_libbpf();
char *log = stop_libbpf_log_capture();
ASSERT_HAS_SUBSTR(log, "... expected ...", "expected some message");
free(log);
As a safety measure, free(start_libbpf_log_capture()) is invoked in the
epilogue of the test_progs.c:run_one_test().
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-6-eddyz87@gmail.com
Diffstat (limited to 'tools')
-rw-r--r-- | tools/testing/selftests/bpf/test_progs.c | 59 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/test_progs.h | 3 |
2 files changed, 62 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index 808550986f30..89ff704e9dad 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -683,11 +683,69 @@ static const struct argp_option opts[] = { {}, }; +static FILE *libbpf_capture_stream; + +static struct { + char *buf; + size_t buf_sz; +} libbpf_output_capture; + +/* Creates a global memstream capturing INFO and WARN level output + * passed to libbpf_print_fn. + * Returns 0 on success, negative value on failure. + * On failure the description is printed using PRINT_FAIL and + * current test case is marked as fail. + */ +int start_libbpf_log_capture(void) +{ + if (libbpf_capture_stream) { + PRINT_FAIL("%s: libbpf_capture_stream != NULL\n", __func__); + return -EINVAL; + } + + libbpf_capture_stream = open_memstream(&libbpf_output_capture.buf, + &libbpf_output_capture.buf_sz); + if (!libbpf_capture_stream) { + PRINT_FAIL("%s: open_memstream failed errno=%d\n", __func__, errno); + return -EINVAL; + } + + return 0; +} + +/* Destroys global memstream created by start_libbpf_log_capture(). + * Returns a pointer to captured data which has to be freed. + * Returned buffer is null terminated. + */ +char *stop_libbpf_log_capture(void) +{ + char *buf; + + if (!libbpf_capture_stream) + return NULL; + + fputc(0, libbpf_capture_stream); + fclose(libbpf_capture_stream); + libbpf_capture_stream = NULL; + /* get 'buf' after fclose(), see open_memstream() documentation */ + buf = libbpf_output_capture.buf; + memset(&libbpf_output_capture, 0, sizeof(libbpf_output_capture)); + return buf; +} + static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args) { + if (libbpf_capture_stream && level != LIBBPF_DEBUG) { + va_list args2; + + va_copy(args2, args); + vfprintf(libbpf_capture_stream, format, args2); + } + if (env.verbosity < VERBOSE_VERY && level == LIBBPF_DEBUG) return 0; + vfprintf(stdout, format, args); return 0; } @@ -1081,6 +1139,7 @@ static void run_one_test(int test_num) cleanup_cgroup_environment(); stdio_restore(); + free(stop_libbpf_log_capture()); dump_test_log(test, state, false, false, NULL); } diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index 80df51244886..0ba5a20b19ba 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -397,6 +397,9 @@ int test__join_cgroup(const char *path); system(cmd); \ }) +int start_libbpf_log_capture(void); +char *stop_libbpf_log_capture(void); + static inline __u64 ptr_to_u64(const void *ptr) { return (__u64) (unsigned long) ptr; |