LXR linux/tools/testing/selftests/bpf/prog_tests/btf

   1// SPDX-License-Identifier: GPL-2.0
   2#include <test_progs.h>
   3#include <bpf/btf.h>
   4
   5static int duration = 0;
   6
   7void btf_dump_printf(void *ctx, const char *fmt, va_list args)
   8{
   9        vfprintf(ctx, fmt, args);
  10}
  11
  12static 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
  26static 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
  43done:
  44        btf_dump__free(d);
  45        return err;
  46}
  47
  48static 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
 114done:
 115        btf__free(btf);
 116        return err;
 117}
 118
 119void 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}
 131