On Sun, Jan 17, 2021 at 2:21 PM Alan Maguire alan.maguire@oracle.com wrote:
Test various type data dumping operations by comparing expected format with the dumped string; an snprintf-style printf function is used to record the string dumped.
Signed-off-by: Alan Maguire alan.maguire@oracle.com
tools/testing/selftests/bpf/prog_tests/btf_dump.c | 233 ++++++++++++++++++++++ 1 file changed, 233 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index c60091e..262561f4 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -232,6 +232,237 @@ void test_btf_dump_incremental(void) btf__free(btf); }
+#define STRSIZE 2048 +#define EXPECTED_STRSIZE 256
+void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{
char *s = ctx, new[STRSIZE];vsnprintf(new, STRSIZE, fmt, args);strncat(s, new, STRSIZE);vfprintf(ctx, fmt, args);+}
+/* skip "enum "/"struct " prefixes */ +#define SKIP_PREFIX(_typestr, _prefix) \
do { \if (strstr(_typestr, _prefix) == _typestr) \
why not strncmp?
_typestr += strlen(_prefix) + 1; \} while (0)+int btf_dump_data(struct btf *btf, struct btf_dump *d,
char *ptrtype, __u64 flags, void *ptr,char *str, char *expectedval)+{
struct btf_dump_emit_type_data_opts opts = { 0 };int ret = 0, cmp;__s32 type_id;opts.sz = sizeof(opts);opts.compact = true;
Please use DECLARE_LIBBPF_OPTS(), check other examples in selftests
if (flags & BTF_F_NONAME)opts.noname = true;if (flags & BTF_F_ZERO)opts.zero = true;SKIP_PREFIX(ptrtype, "enum");SKIP_PREFIX(ptrtype, "struct");SKIP_PREFIX(ptrtype, "union");type_id = btf__find_by_name(btf, ptrtype);if (CHECK(type_id <= 0, "find type id","no '%s' in BTF: %d\n", ptrtype, type_id)) {ret = -ENOENT;goto err;}str[0] = '\0';ret = btf_dump__emit_type_data(d, type_id, &opts, ptr);if (CHECK(ret < 0, "btf_dump__emit_type_data","failed: %d\n", ret))goto err;cmp = strncmp(str, expectedval, EXPECTED_STRSIZE);if (CHECK(cmp, "ensure expected/actual match","'%s' does not match expected '%s': %d\n",str, expectedval, cmp))ret = -EFAULT;+err:
if (ret)btf_dump__free(d);return ret;+}
+#define TEST_BTF_DUMP_DATA(_b, _d, _str, _type, _flags, _expected, ...) \
do { \char _expectedval[EXPECTED_STRSIZE] = _expected; \char __ptrtype[64] = #_type; \char *_ptrtype = (char *)__ptrtype; \static _type _ptrdata = __VA_ARGS__; \void *_ptr = &_ptrdata; \\if (btf_dump_data(_b, _d, _ptrtype, _flags, _ptr, \_str, _expectedval)) \return; \} while (0)+/* Use where expected data string matches its stringified declaration */ +#define TEST_BTF_DUMP_DATA_C(_b, _d, _str, _type, _opts, ...) \
TEST_BTF_DUMP_DATA(_b, _d, _str, _type, _opts, \"(" #_type ")" #__VA_ARGS__, __VA_ARGS__)+void test_btf_dump_data(void) +{
struct btf *btf = libbpf_find_kernel_btf();char str[STRSIZE];struct btf_dump_opts opts = { .ctx = str };struct btf_dump *d;if (CHECK(!btf, "get kernel BTF", "no kernel BTF found"))return;
use libbpf_get_error(), btf won't be NULL on error
d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf);if (CHECK(!d, "new dump", "could not create BTF dump"))
same, d won't be NULL on error
return;/* Verify type display for various types. */
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