1 files changed, 143 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/test_btf_dump.c b/tools/testing/selftests/bpf/test_btf_dump.c
new file mode 100644
index 000000000000..8f850823d35f
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_btf_dump.c
@@ -0,0 +1,143 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <linux/err.h>
+#include <btf.h>
+
+#define CHECK(condition, format...) ({                                  \
+        int __ret = !!(condition);                                      \
+        if (__ret) {                                                    \
+                fprintf(stderr, "%s:%d:FAIL ", __func__, __LINE__);     \
+                fprintf(stderr, format);                                \
+        }                                                               \
+        __ret;                                                          \
+})
+
+void btf_dump_printf(void *ctx, const char *fmt, va_list args)
+{
+        vfprintf(ctx, fmt, args);
+}
+
+struct btf_dump_test_case {
+        const char *name;
+        struct btf_dump_opts opts;
+} btf_dump_test_cases[] = {
+        {.name = "btf_dump_test_case_syntax", .opts = {}},
+        {.name = "btf_dump_test_case_ordering", .opts = {}},
+        {.name = "btf_dump_test_case_padding", .opts = {}},
+        {.name = "btf_dump_test_case_packing", .opts = {}},
+        {.name = "btf_dump_test_case_bitfields", .opts = {}},
+        {.name = "btf_dump_test_case_multidim", .opts = {}},
+        {.name = "btf_dump_test_case_namespacing", .opts = {}},
+};
+
+static int btf_dump_all_types(const struct btf *btf,
+                              const struct btf_dump_opts *opts)
+{
+        size_t type_cnt = btf__get_nr_types(btf);
+        struct btf_dump *d;
+        int err = 0, id;
+
+        d = btf_dump__new(btf, NULL, opts, btf_dump_printf);
+        if (IS_ERR(d))
+                return PTR_ERR(d);
+
+        for (id = 1; id <= type_cnt; id++) {
+                err = btf_dump__dump_type(d, id);
+                if (err)
+                        goto done;
+        }
+
+done:
+        btf_dump__free(d);
+        return err;
+}
+
+int test_btf_dump_case(int n, struct btf_dump_test_case *test_case)
+{
+        char test_file[256], out_file[256], diff_cmd[1024];
+        struct btf *btf = NULL;
+        int err = 0, fd = -1;
+        FILE *f = NULL;
+
+        fprintf(stderr, "Test case #%d (%s): ", n, test_case->name);
+
+        snprintf(test_file, sizeof(test_file), "%s.o", test_case->name);
+
+        btf = btf__parse_elf(test_file, NULL);
+        if (CHECK(IS_ERR(btf),
+            "failed to load test BTF: %ld\n", PTR_ERR(btf))) {
+                err = -PTR_ERR(btf);
+                btf = NULL;
+                goto done;
+        }
+
+        snprintf(out_file, sizeof(out_file),
+                 "/tmp/%s.output.XXXXXX", test_case->name);
+        fd = mkstemp(out_file);
+        if (CHECK(fd < 0, "failed to create temp output file: %d\n", fd)) {
+                err = fd;
+                goto done;
+        }
+        f = fdopen(fd, "w");
+        if (CHECK(f == NULL, "failed to open temp output file: %s(%d)\n",
+                  strerror(errno), errno)) {
+                close(fd);
+                goto done;
+        }
+
+        test_case->opts.ctx = f;
+        err = btf_dump_all_types(btf, &test_case->opts);
+        fclose(f);
+        close(fd);
+        if (CHECK(err, "failure during C dumping: %d\n", err)) {
+                goto done;
+        }
+
+        snprintf(test_file, sizeof(test_file), "progs/%s.c", test_case->name);
+        /*
+         * Diff test output and expected test output, contained between
+         * START-EXPECTED-OUTPUT and END-EXPECTED-OUTPUT lines in test case.
+         * For expected output lines, everything before '*' is stripped out.
+         * Also lines containing comment start and comment end markers are
+         * ignored. 
+         */
+        snprintf(diff_cmd, sizeof(diff_cmd),
+                 "awk '/START-EXPECTED-OUTPUT/{out=1;next} "
+                 "/END-EXPECTED-OUTPUT/{out=0} "
+                 "/\\/\\*|\\*\\//{next} " /* ignore comment start/end lines */
+                 "out {sub(/^[ \\t]*\\*/, \"\"); print}' '%s' | diff -u - '%s'",
+                 test_file, out_file);
+        err = system(diff_cmd);
+        if (CHECK(err,
+                  "differing test output, output=%s, err=%d, diff cmd:\n%s\n",
+                  out_file, err, diff_cmd))
+                goto done;
+
+        remove(out_file);
+        fprintf(stderr, "OK\n");
+
+done:
+        btf__free(btf);
+        return err;
+}
+
+int main() {
+        int test_case_cnt, i, err, failed = 0;
+
+        test_case_cnt = sizeof(btf_dump_test_cases) /
+                        sizeof(btf_dump_test_cases[0]);
+
+        for (i = 0; i < test_case_cnt; i++) {
+                err = test_btf_dump_case(i, &btf_dump_test_cases[i]);
+                if (err)
+                        failed++;
+        }
+
+        fprintf(stderr, "%d tests succeeded, %d tests failed.\n",
+                test_case_cnt - failed, failed);
+
+        return failed;
+}