diff options
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/btf_dump.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index 39fb81d9daeb..c60091ee8a21 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -129,6 +129,109 @@ done: return err; } +static char *dump_buf; +static size_t dump_buf_sz; +static FILE *dump_buf_file; + +void test_btf_dump_incremental(void) +{ + struct btf *btf = NULL; + struct btf_dump *d = NULL; + struct btf_dump_opts opts; + int id, err, i; + + dump_buf_file = open_memstream(&dump_buf, &dump_buf_sz); + if (!ASSERT_OK_PTR(dump_buf_file, "dump_memstream")) + return; + btf = btf__new_empty(); + if (!ASSERT_OK_PTR(btf, "new_empty")) + goto err_out; + opts.ctx = dump_buf_file; + d = btf_dump__new(btf, NULL, &opts, btf_dump_printf); + if (!ASSERT_OK(libbpf_get_error(d), "btf_dump__new")) + goto err_out; + + /* First, generate BTF corresponding to the following C code: + * + * enum { VAL = 1 }; + * + * struct s { int x; }; + * + */ + id = btf__add_enum(btf, NULL, 4); + ASSERT_EQ(id, 1, "enum_id"); + err = btf__add_enum_value(btf, "VAL", 1); + ASSERT_OK(err, "enum_val_ok"); + + id = btf__add_int(btf, "int", 4, BTF_INT_SIGNED); + ASSERT_EQ(id, 2, "int_id"); + + id = btf__add_struct(btf, "s", 4); + ASSERT_EQ(id, 3, "struct_id"); + err = btf__add_field(btf, "x", 2, 0, 0); + ASSERT_OK(err, "field_ok"); + + for (i = 1; i <= btf__get_nr_types(btf); i++) { + err = btf_dump__dump_type(d, i); + ASSERT_OK(err, "dump_type_ok"); + } + + fflush(dump_buf_file); + dump_buf[dump_buf_sz] = 0; /* some libc implementations don't do this */ + ASSERT_STREQ(dump_buf, +"enum {\n" +" VAL = 1,\n" +"};\n" +"\n" +"struct s {\n" +" int x;\n" +"};\n\n", "c_dump1"); + + /* Now, after dumping original BTF, append another struct that embeds + * anonymous enum. It also has a name conflict with the first struct: + * + * struct s___2 { + * enum { VAL___2 = 1 } x; + * struct s s; + * }; + * + * This will test that btf_dump'er maintains internal state properly. + * Note that VAL___2 enum value. It's because we've already emitted + * that enum as a global anonymous enum, so btf_dump will ensure that + * enum values don't conflict; + * + */ + fseek(dump_buf_file, 0, SEEK_SET); + + id = btf__add_struct(btf, "s", 4); + ASSERT_EQ(id, 4, "struct_id"); + err = btf__add_field(btf, "x", 1, 0, 0); + ASSERT_OK(err, "field_ok"); + err = btf__add_field(btf, "s", 3, 32, 0); + ASSERT_OK(err, "field_ok"); + + for (i = 1; i <= btf__get_nr_types(btf); i++) { + err = btf_dump__dump_type(d, i); + ASSERT_OK(err, "dump_type_ok"); + } + + fflush(dump_buf_file); + dump_buf[dump_buf_sz] = 0; /* some libc implementations don't do this */ + ASSERT_STREQ(dump_buf, +"struct s___2 {\n" +" enum {\n" +" VAL___2 = 1,\n" +" } x;\n" +" struct s s;\n" +"};\n\n" , "c_dump1"); + +err_out: + fclose(dump_buf_file); + free(dump_buf); + btf_dump__free(d); + btf__free(btf); +} + void test_btf_dump() { int i; @@ -140,4 +243,6 @@ void test_btf_dump() { test_btf_dump_case(i, &btf_dump_test_cases[i]); } + if (test__start_subtest("btf_dump: incremental")) + test_btf_dump_incremental(); } |