tools/testing/selftests/bpf/prog_tests/btf_dump.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3 #include <bpf/btf.h>
   4
   5 static int duration = 0;
   6
   7 void btf_dump_printf(void *ctx, const char *fmt, va_list args)
   8 {
   9         vfprintf(ctx, fmt, args);
  10 }
  11
  12 static struct btf_dump_test_case {
  13         const char *name;
  14         const char *file;
  15         struct btf_dump_opts opts;
  16 } btf_dump_test_cases[] = {
  17         {"btf_dump: syntax", "btf_dump_test_case_syntax", {}},
  18         {"btf_dump: ordering", "btf_dump_test_case_ordering", {}},
  19         {"btf_dump: padding", "btf_dump_test_case_padding", {}},
  20         {"btf_dump: packing", "btf_dump_test_case_packing", {}},
  21         {"btf_dump: bitfields", "btf_dump_test_case_bitfields", {}},
  22         {"btf_dump: multidim", "btf_dump_test_case_multidim", {}},
  23         {"btf_dump: namespacing", "btf_dump_test_case_namespacing", {}},
  24 };
  25
  26 static int btf_dump_all_types(const struct btf *btf,
  27                               const struct btf_dump_opts *opts)
  28 {
  29         size_t type_cnt = btf__get_nr_types(btf);
  30         struct btf_dump *d;
  31         int err = 0, id;
  32
  33         d = btf_dump__new(btf, NULL, opts, btf_dump_printf);
  34         if (IS_ERR(d))
  35                 return PTR_ERR(d);
  36
  37         for (id = 1; id <= type_cnt; id++) {
  38                 err = btf_dump__dump_type(d, id);
  39                 if (err)
  40                         goto done;
  41         }
  42
  43 done:
  44         btf_dump__free(d);
  45         return err;
  46 }
  47
  48 static int test_btf_dump_case(int n, struct btf_dump_test_case *t)
  49 {
  50         char test_file[256], out_file[256], diff_cmd[1024];
  51         struct btf *btf = NULL;
  52         int err = 0, fd = -1;
  53         FILE *f = NULL;
  54
  55         snprintf(test_file, sizeof(test_file), "%s.o", t->file);
  56
  57         btf = btf__parse_elf(test_file, NULL);
  58         if (CHECK(IS_ERR(btf), "btf_parse_elf",
  59             "failed to load test BTF: %ld\n", PTR_ERR(btf))) {
  60                 err = -PTR_ERR(btf);
  61                 btf = NULL;
  62                 goto done;
  63         }
  64
  65         snprintf(out_file, sizeof(out_file), "/tmp/%s.output.XXXXXX", t->file);
  66         fd = mkstemp(out_file);
  67         if (CHECK(fd < 0, "create_tmp", "failed to create file: %d\n", fd)) {
  68                 err = fd;
  69                 goto done;
  70         }
  71         f = fdopen(fd, "w");
  72         if (CHECK(f == NULL, "open_tmp",  "failed to open file: %s(%d)\n",
  73                   strerror(errno), errno)) {
  74                 close(fd);
  75                 goto done;
  76         }
  77
  78         t->opts.ctx = f;
  79         err = btf_dump_all_types(btf, &t->opts);
  80         fclose(f);
  81         close(fd);
  82         if (CHECK(err, "btf_dump", "failure during C dumping: %d\n", err)) {
  83                 goto done;
  84         }
  85
  86         snprintf(test_file, sizeof(test_file), "progs/%s.c", t->file);
  87         if (access(test_file, R_OK) == -1)
  88                 /*
  89                  * When the test is run with O=, kselftest copies TEST_FILES
  90                  * without preserving the directory structure.
  91                  */
  92                 snprintf(test_file, sizeof(test_file), "%s.c", t->file);
  93         /*
  94          * Diff test output and expected test output, contained between
  95          * START-EXPECTED-OUTPUT and END-EXPECTED-OUTPUT lines in test case.
  96          * For expected output lines, everything before '*' is stripped out.
  97          * Also lines containing comment start and comment end markers are
  98          * ignored.
  99          */
 100         snprintf(diff_cmd, sizeof(diff_cmd),
 101                  "awk '/START-EXPECTED-OUTPUT/{out=1;next} "
 102                  "/END-EXPECTED-OUTPUT/{out=0} "
 103                  "/\\/\\*|\\*\\//{next} " /* ignore comment start/end lines */
 104                  "out {sub(/^[ \\t]*\\*/, \"\"); print}' '%s' | diff -u - '%s'",
 105                  test_file, out_file);
 106         err = system(diff_cmd);
 107         if (CHECK(err, "diff",
 108                   "differing test output, output=%s, err=%d, diff cmd:\n%s\n",
 109                   out_file, err, diff_cmd))
 110                 goto done;
 111
 112         remove(out_file);
 113
 114 done:
 115         btf__free(btf);
 116         return err;
 117 }
 118
 119 void test_btf_dump() {
 120         int i;
 121
 122         for (i = 0; i < ARRAY_SIZE(btf_dump_test_cases); i++) {
 123                 struct btf_dump_test_case *t = &btf_dump_test_cases[i];
 124
 125                 if (!test__start_subtest(t->name))
 126                         continue;
 127
 128                 test_btf_dump_case(i, &btf_dump_test_cases[i]);
 129         }
 130 }