// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include <stdio.h>
#include <errno.h>
#include <bpf/btf.h>
#include <bpf/libbpf.h>
#include "test_progs.h"
static const char * const btf_kind_str_mapping[] = {
[BTF_KIND_UNKN] = "UNKNOWN",
[BTF_KIND_INT] = "INT",
[BTF_KIND_PTR] = "PTR",
[BTF_KIND_ARRAY] = "ARRAY",
[BTF_KIND_STRUCT] = "STRUCT",
[BTF_KIND_UNION] = "UNION",
[BTF_KIND_ENUM] = "ENUM",
[BTF_KIND_FWD] = "FWD",
[BTF_KIND_TYPEDEF] = "TYPEDEF",
[BTF_KIND_VOLATILE] = "VOLATILE",
[BTF_KIND_CONST] = "CONST",
[BTF_KIND_RESTRICT] = "RESTRICT",
[BTF_KIND_FUNC] = "FUNC",
[BTF_KIND_FUNC_PROTO] = "FUNC_PROTO",
[BTF_KIND_VAR] = "VAR",
[BTF_KIND_DATASEC] = "DATASEC",
[BTF_KIND_FLOAT] = "FLOAT",
[BTF_KIND_DECL_TAG] = "DECL_TAG",
[BTF_KIND_TYPE_TAG] = "TYPE_TAG",
[BTF_KIND_ENUM64] = "ENUM64",
};
static const char *btf_kind_str(__u16 kind)
{
if (kind > BTF_KIND_ENUM64)
return "UNKNOWN";
return btf_kind_str_mapping[kind];
}
static const char *btf_int_enc_str(__u8 encoding)
{
switch (encoding) {
case 0:
return "(none)";
case BTF_INT_SIGNED:
return "SIGNED";
case BTF_INT_CHAR:
return "CHAR";
case BTF_INT_BOOL:
return "BOOL";
default:
return "UNKN";
}
}
static const char *btf_var_linkage_str(__u32 linkage)
{
switch (linkage) {
case BTF_VAR_STATIC:
return "static";
case BTF_VAR_GLOBAL_ALLOCATED:
return "global-alloc";
default:
return "(unknown)";
}
}
static const char *btf_func_linkage_str(const struct btf_type *t)
{
switch (btf_vlen(t)) {
case BTF_FUNC_STATIC:
return "static";
case BTF_FUNC_GLOBAL:
return "global";
case BTF_FUNC_EXTERN:
return "extern";
default:
return "(unknown)";
}
}
static const char *btf_str(const struct btf *btf, __u32 off)
{
if (!off)
return "(anon)";
return btf__str_by_offset(btf, off) ?: "(invalid)";
}
int fprintf_btf_type_raw(FILE *out, const struct btf *btf, __u32 id)
{
const struct btf_type *t;
int kind, i;
__u32 vlen;
t = btf__type_by_id(btf, id);
if (!t)
return -EINVAL;
vlen = btf_vlen(t);
kind = btf_kind(t);
fprintf(out, "[%u] %s '%s'", id, btf_kind_str(kind), btf_str(btf, t->name_off));
switch (kind) {
case BTF_KIND_INT:
fprintf(out, " size=%u bits_offset=%u nr_bits=%u encoding=%s",
t->size, btf_int_offset(t), btf_int_bits(t),
btf_int_enc_str(btf_int_encoding(t)));
break;
case BTF_KIND_PTR:
case BTF_KIND_CONST:
case BTF_KIND_VOLATILE:
case BTF_KIND_RESTRICT:
case BTF_KIND_TYPEDEF:
case BTF_KIND_TYPE_TAG:
fprintf(out, " type_id=%u", t->type);
break;
case BTF_KIND_ARRAY: {
const struct btf_array *arr = btf_array(t);
fprintf(out, " type_id=%u index_type_id=%u nr_elems=%u",
arr->type, arr->index_type, arr->nelems);
break;
}
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
const struct btf_member *m = btf_members(t);
fprintf(out, " size=%u vlen=%u", t->size, vlen);
for (i = 0; i < vlen; i++, m++) {
__u32 bit_off, bit_sz;
bit_off = btf_member_bit_offset(t, i);
bit_sz = btf_member_bitfield_size(t, i);
fprintf(out, "\n\t'%s' type_id=%u bits_offset=%u",
btf_str(btf, m->name_off), m->type, bit_off);
if (bit_sz)
fprintf(out, " bitfield_size=%u", bit_sz);
}
break;
}
case BTF_KIND_ENUM: {
const struct btf_enum *v = btf_enum(t);
const char *fmt_str;
fmt_str = btf_kflag(t) ? "\n\t'%s' val=%d" : "\n\t'%s' val=%u";
fprintf(out, " encoding=%s size=%u vlen=%u",
btf_kflag(t) ? "SIGNED" : "UNSIGNED", t->size, vlen);
for (i = 0; i < vlen; i++, v++) {
fprintf(out, fmt_str,
btf_str(btf, v->name_off), v->val);
}
break;
}
case BTF_KIND_ENUM64: {
const struct btf_enum64 *v = btf_enum64(t);
const char *fmt_str;
fmt_str = btf_kflag(t) ? "\n\t'%s' val=%lld" : "\n\t'%s' val=%llu";
fprintf(out, " encoding=%s size=%u vlen=%u",
btf_kflag(t) ? "SIGNED" : "UNSIGNED", t->size, vlen);
for (i = 0; i < vlen; i++, v++) {
fprintf(out, fmt_str,
btf_str(btf, v->name_off),
((__u64)v->val_hi32 << 32) | v->val_lo32);
}
break;
}
case BTF_KIND_FWD:
fprintf(out, " fwd_kind=%s", btf_kflag(t) ? "union" : "struct");
break;
case BTF_KIND_FUNC:
fprintf(out, " type_id=%u linkage=%s", t->type, btf_func_linkage_str(t));
break;
case BTF_KIND_FUNC_PROTO: {
const struct btf_param *p = btf_params(t);
fprintf(out, " ret_type_id=%u vlen=%u", t->type, vlen);
for (i = 0; i < vlen; i++, p++) {
fprintf(out, "\n\t'%s' type_id=%u",
btf_str(btf, p->name_off), p->type);
}
break;
}
case BTF_KIND_VAR:
fprintf(out, " type_id=%u, linkage=%s",
t->type, btf_var_linkage_str(btf_var(t)->linkage));
break;
case BTF_KIND_DATASEC: {
const struct btf_var_secinfo *v = btf_var_secinfos(t);
fprintf(out, " size=%u vlen=%u", t->size, vlen);
for (i = 0; i < vlen; i++, v++) {
fprintf(out, "\n\ttype_id=%u offset=%u size=%u",
v->type, v->offset, v->size);
}
break;
}
case BTF_KIND_FLOAT:
fprintf(out, " size=%u", t->size);
break;
case BTF_KIND_DECL_TAG:
fprintf(out, " type_id=%u component_idx=%d",
t->type, btf_decl_tag(t)->component_idx);
break;
default:
break;
}
return 0;
}
/* Print raw BTF type dump into a local buffer and return string pointer back.
* Buffer *will* be overwritten by subsequent btf_type_raw_dump() calls
*/
const char *btf_type_raw_dump(const struct btf *btf, int type_id)
{
static char buf[16 * 1024];
FILE *buf_file;
buf_file = fmemopen(buf, sizeof(buf) - 1, "w");
if (!buf_file) {
fprintf(stderr, "Failed to open memstream: %d\n", errno);
return NULL;
}
fprintf_btf_type_raw(buf_file, btf, type_id);
fflush(buf_file);
fclose(buf_file);
return buf;
}
int btf_validate_raw(struct btf *btf, int nr_types, const char *exp_types[])
{
int i;
bool ok = true;
ASSERT_EQ(btf__type_cnt(btf) - 1, nr_types, "btf_nr_types");
for (i = 1; i <= nr_types; i++) {
if (!ASSERT_STREQ(btf_type_raw_dump(btf, i), exp_types[i - 1], "raw_dump"))
ok = false;
}
return ok;
}
static void btf_dump_printf(void *ctx, const char *fmt, va_list args)
{
vfprintf(ctx, fmt, args);
}
/* Print BTF-to-C dump into a local buffer and return string pointer back.
* Buffer *will* be overwritten by subsequent btf_type_raw_dump() calls
*/
const char *btf_type_c_dump(const struct btf *btf)
{
static char buf[16 * 1024];
FILE *buf_file;
struct btf_dump *d = NULL;
int err, i;
buf_file = fmemopen(buf, sizeof(buf) - 1, "w");
if (!buf_file) {
fprintf(stderr, "Failed to open memstream: %d\n", errno);
return NULL;
}
d = btf_dump__new(btf, btf_dump_printf, buf_file, NULL);
if (libbpf_get_error(d)) {
fprintf(stderr, "Failed to create btf_dump instance: %ld\n", libbpf_get_error(d));
goto err_out;
}
for (i = 1; i < btf__type_cnt(btf); i++) {
err = btf_dump__dump_type(d, i);
if (err) {
fprintf(stderr, "Failed to dump type [%d]: %d\n", i, err);
goto err_out;
}
}
btf_dump__free(d);
fflush(buf_file);
fclose(buf_file);
return buf;
err_out:
btf_dump__free(d);
fclose(buf_file);
return NULL;
}
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