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-rw-r--r--tools/bpf/bpftool/btf_dumper.c783
1 files changed, 783 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
new file mode 100644
index 000000000..13be48763
--- /dev/null
+++ b/tools/bpf/bpftool/btf_dumper.c
@@ -0,0 +1,783 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (c) 2018 Facebook */
+
+#include <ctype.h>
+#include <stdio.h> /* for (FILE *) used by json_writer */
+#include <string.h>
+#include <unistd.h>
+#include <asm/byteorder.h>
+#include <linux/bitops.h>
+#include <linux/btf.h>
+#include <linux/err.h>
+#include <bpf/btf.h>
+#include <bpf/bpf.h>
+
+#include "json_writer.h"
+#include "main.h"
+
+#define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1)
+#define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK)
+#define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3)
+#define BITS_ROUNDUP_BYTES(bits) \
+ (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
+
+static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
+ __u8 bit_offset, const void *data);
+
+static int btf_dump_func(const struct btf *btf, char *func_sig,
+ const struct btf_type *func_proto,
+ const struct btf_type *func, int pos, int size);
+
+static int dump_prog_id_as_func_ptr(const struct btf_dumper *d,
+ const struct btf_type *func_proto,
+ __u32 prog_id)
+{
+ struct bpf_prog_info_linear *prog_info = NULL;
+ const struct btf_type *func_type;
+ const char *prog_name = NULL;
+ struct bpf_func_info *finfo;
+ struct btf *prog_btf = NULL;
+ struct bpf_prog_info *info;
+ int prog_fd, func_sig_len;
+ char prog_str[1024];
+
+ /* Get the ptr's func_proto */
+ func_sig_len = btf_dump_func(d->btf, prog_str, func_proto, NULL, 0,
+ sizeof(prog_str));
+ if (func_sig_len == -1)
+ return -1;
+
+ if (!prog_id)
+ goto print;
+
+ /* Get the bpf_prog's name. Obtain from func_info. */
+ prog_fd = bpf_prog_get_fd_by_id(prog_id);
+ if (prog_fd == -1)
+ goto print;
+
+ prog_info = bpf_program__get_prog_info_linear(prog_fd,
+ 1UL << BPF_PROG_INFO_FUNC_INFO);
+ close(prog_fd);
+ if (IS_ERR(prog_info)) {
+ prog_info = NULL;
+ goto print;
+ }
+ info = &prog_info->info;
+
+ if (!info->btf_id || !info->nr_func_info ||
+ btf__get_from_id(info->btf_id, &prog_btf))
+ goto print;
+ finfo = u64_to_ptr(info->func_info);
+ func_type = btf__type_by_id(prog_btf, finfo->type_id);
+ if (!func_type || !btf_is_func(func_type))
+ goto print;
+
+ prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
+
+print:
+ if (!prog_id)
+ snprintf(&prog_str[func_sig_len],
+ sizeof(prog_str) - func_sig_len, " 0");
+ else if (prog_name)
+ snprintf(&prog_str[func_sig_len],
+ sizeof(prog_str) - func_sig_len,
+ " %s/prog_id:%u", prog_name, prog_id);
+ else
+ snprintf(&prog_str[func_sig_len],
+ sizeof(prog_str) - func_sig_len,
+ " <unknown_prog_name>/prog_id:%u", prog_id);
+
+ prog_str[sizeof(prog_str) - 1] = '\0';
+ jsonw_string(d->jw, prog_str);
+ btf__free(prog_btf);
+ free(prog_info);
+ return 0;
+}
+
+static void btf_dumper_ptr(const struct btf_dumper *d,
+ const struct btf_type *t,
+ const void *data)
+{
+ unsigned long value = *(unsigned long *)data;
+ const struct btf_type *ptr_type;
+ __s32 ptr_type_id;
+
+ if (!d->prog_id_as_func_ptr || value > UINT32_MAX)
+ goto print_ptr_value;
+
+ ptr_type_id = btf__resolve_type(d->btf, t->type);
+ if (ptr_type_id < 0)
+ goto print_ptr_value;
+ ptr_type = btf__type_by_id(d->btf, ptr_type_id);
+ if (!ptr_type || !btf_is_func_proto(ptr_type))
+ goto print_ptr_value;
+
+ if (!dump_prog_id_as_func_ptr(d, ptr_type, value))
+ return;
+
+print_ptr_value:
+ if (d->is_plain_text)
+ jsonw_printf(d->jw, "%p", (void *)value);
+ else
+ jsonw_printf(d->jw, "%lu", value);
+}
+
+static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id,
+ __u8 bit_offset, const void *data)
+{
+ int actual_type_id;
+
+ actual_type_id = btf__resolve_type(d->btf, type_id);
+ if (actual_type_id < 0)
+ return actual_type_id;
+
+ return btf_dumper_do_type(d, actual_type_id, bit_offset, data);
+}
+
+static int btf_dumper_enum(const struct btf_dumper *d,
+ const struct btf_type *t,
+ const void *data)
+{
+ const struct btf_enum *enums = btf_enum(t);
+ __s64 value;
+ __u16 i;
+
+ switch (t->size) {
+ case 8:
+ value = *(__s64 *)data;
+ break;
+ case 4:
+ value = *(__s32 *)data;
+ break;
+ case 2:
+ value = *(__s16 *)data;
+ break;
+ case 1:
+ value = *(__s8 *)data;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = 0; i < btf_vlen(t); i++) {
+ if (value == enums[i].val) {
+ jsonw_string(d->jw,
+ btf__name_by_offset(d->btf,
+ enums[i].name_off));
+ return 0;
+ }
+ }
+
+ jsonw_int(d->jw, value);
+ return 0;
+}
+
+static bool is_str_array(const struct btf *btf, const struct btf_array *arr,
+ const char *s)
+{
+ const struct btf_type *elem_type;
+ const char *end_s;
+
+ if (!arr->nelems)
+ return false;
+
+ elem_type = btf__type_by_id(btf, arr->type);
+ /* Not skipping typedef. typedef to char does not count as
+ * a string now.
+ */
+ while (elem_type && btf_is_mod(elem_type))
+ elem_type = btf__type_by_id(btf, elem_type->type);
+
+ if (!elem_type || !btf_is_int(elem_type) || elem_type->size != 1)
+ return false;
+
+ if (btf_int_encoding(elem_type) != BTF_INT_CHAR &&
+ strcmp("char", btf__name_by_offset(btf, elem_type->name_off)))
+ return false;
+
+ end_s = s + arr->nelems;
+ while (s < end_s) {
+ if (!*s)
+ return true;
+ if (*s <= 0x1f || *s >= 0x7f)
+ return false;
+ s++;
+ }
+
+ /* '\0' is not found */
+ return false;
+}
+
+static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id,
+ const void *data)
+{
+ const struct btf_type *t = btf__type_by_id(d->btf, type_id);
+ struct btf_array *arr = (struct btf_array *)(t + 1);
+ long long elem_size;
+ int ret = 0;
+ __u32 i;
+
+ if (is_str_array(d->btf, arr, data)) {
+ jsonw_string(d->jw, data);
+ return 0;
+ }
+
+ elem_size = btf__resolve_size(d->btf, arr->type);
+ if (elem_size < 0)
+ return elem_size;
+
+ jsonw_start_array(d->jw);
+ for (i = 0; i < arr->nelems; i++) {
+ ret = btf_dumper_do_type(d, arr->type, 0,
+ data + i * elem_size);
+ if (ret)
+ break;
+ }
+
+ jsonw_end_array(d->jw);
+ return ret;
+}
+
+static void btf_int128_print(json_writer_t *jw, const void *data,
+ bool is_plain_text)
+{
+ /* data points to a __int128 number.
+ * Suppose
+ * int128_num = *(__int128 *)data;
+ * The below formulas shows what upper_num and lower_num represents:
+ * upper_num = int128_num >> 64;
+ * lower_num = int128_num & 0xffffffffFFFFFFFFULL;
+ */
+ __u64 upper_num, lower_num;
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ upper_num = *(__u64 *)data;
+ lower_num = *(__u64 *)(data + 8);
+#else
+ upper_num = *(__u64 *)(data + 8);
+ lower_num = *(__u64 *)data;
+#endif
+
+ if (is_plain_text) {
+ if (upper_num == 0)
+ jsonw_printf(jw, "0x%llx", lower_num);
+ else
+ jsonw_printf(jw, "0x%llx%016llx", upper_num, lower_num);
+ } else {
+ if (upper_num == 0)
+ jsonw_printf(jw, "\"0x%llx\"", lower_num);
+ else
+ jsonw_printf(jw, "\"0x%llx%016llx\"", upper_num, lower_num);
+ }
+}
+
+static void btf_int128_shift(__u64 *print_num, __u16 left_shift_bits,
+ __u16 right_shift_bits)
+{
+ __u64 upper_num, lower_num;
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ upper_num = print_num[0];
+ lower_num = print_num[1];
+#else
+ upper_num = print_num[1];
+ lower_num = print_num[0];
+#endif
+
+ /* shake out un-needed bits by shift/or operations */
+ if (left_shift_bits >= 64) {
+ upper_num = lower_num << (left_shift_bits - 64);
+ lower_num = 0;
+ } else {
+ upper_num = (upper_num << left_shift_bits) |
+ (lower_num >> (64 - left_shift_bits));
+ lower_num = lower_num << left_shift_bits;
+ }
+
+ if (right_shift_bits >= 64) {
+ lower_num = upper_num >> (right_shift_bits - 64);
+ upper_num = 0;
+ } else {
+ lower_num = (lower_num >> right_shift_bits) |
+ (upper_num << (64 - right_shift_bits));
+ upper_num = upper_num >> right_shift_bits;
+ }
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ print_num[0] = upper_num;
+ print_num[1] = lower_num;
+#else
+ print_num[0] = lower_num;
+ print_num[1] = upper_num;
+#endif
+}
+
+static void btf_dumper_bitfield(__u32 nr_bits, __u8 bit_offset,
+ const void *data, json_writer_t *jw,
+ bool is_plain_text)
+{
+ int left_shift_bits, right_shift_bits;
+ __u64 print_num[2] = {};
+ int bytes_to_copy;
+ int bits_to_copy;
+
+ bits_to_copy = bit_offset + nr_bits;
+ bytes_to_copy = BITS_ROUNDUP_BYTES(bits_to_copy);
+
+ memcpy(print_num, data, bytes_to_copy);
+#if defined(__BIG_ENDIAN_BITFIELD)
+ left_shift_bits = bit_offset;
+#elif defined(__LITTLE_ENDIAN_BITFIELD)
+ left_shift_bits = 128 - bits_to_copy;
+#else
+#error neither big nor little endian
+#endif
+ right_shift_bits = 128 - nr_bits;
+
+ btf_int128_shift(print_num, left_shift_bits, right_shift_bits);
+ btf_int128_print(jw, print_num, is_plain_text);
+}
+
+
+static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset,
+ const void *data, json_writer_t *jw,
+ bool is_plain_text)
+{
+ int nr_bits = BTF_INT_BITS(int_type);
+ int total_bits_offset;
+
+ /* bits_offset is at most 7.
+ * BTF_INT_OFFSET() cannot exceed 128 bits.
+ */
+ total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type);
+ data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
+ bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
+ btf_dumper_bitfield(nr_bits, bit_offset, data, jw,
+ is_plain_text);
+}
+
+static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset,
+ const void *data, json_writer_t *jw,
+ bool is_plain_text)
+{
+ __u32 *int_type;
+ __u32 nr_bits;
+
+ int_type = (__u32 *)(t + 1);
+ nr_bits = BTF_INT_BITS(*int_type);
+ /* if this is bit field */
+ if (bit_offset || BTF_INT_OFFSET(*int_type) ||
+ BITS_PER_BYTE_MASKED(nr_bits)) {
+ btf_dumper_int_bits(*int_type, bit_offset, data, jw,
+ is_plain_text);
+ return 0;
+ }
+
+ if (nr_bits == 128) {
+ btf_int128_print(jw, data, is_plain_text);
+ return 0;
+ }
+
+ switch (BTF_INT_ENCODING(*int_type)) {
+ case 0:
+ if (BTF_INT_BITS(*int_type) == 64)
+ jsonw_printf(jw, "%llu", *(__u64 *)data);
+ else if (BTF_INT_BITS(*int_type) == 32)
+ jsonw_printf(jw, "%u", *(__u32 *)data);
+ else if (BTF_INT_BITS(*int_type) == 16)
+ jsonw_printf(jw, "%hu", *(__u16 *)data);
+ else if (BTF_INT_BITS(*int_type) == 8)
+ jsonw_printf(jw, "%hhu", *(__u8 *)data);
+ else
+ btf_dumper_int_bits(*int_type, bit_offset, data, jw,
+ is_plain_text);
+ break;
+ case BTF_INT_SIGNED:
+ if (BTF_INT_BITS(*int_type) == 64)
+ jsonw_printf(jw, "%lld", *(long long *)data);
+ else if (BTF_INT_BITS(*int_type) == 32)
+ jsonw_printf(jw, "%d", *(int *)data);
+ else if (BTF_INT_BITS(*int_type) == 16)
+ jsonw_printf(jw, "%hd", *(short *)data);
+ else if (BTF_INT_BITS(*int_type) == 8)
+ jsonw_printf(jw, "%hhd", *(char *)data);
+ else
+ btf_dumper_int_bits(*int_type, bit_offset, data, jw,
+ is_plain_text);
+ break;
+ case BTF_INT_CHAR:
+ if (isprint(*(char *)data))
+ jsonw_printf(jw, "\"%c\"", *(char *)data);
+ else
+ if (is_plain_text)
+ jsonw_printf(jw, "0x%hhx", *(char *)data);
+ else
+ jsonw_printf(jw, "\"\\u00%02hhx\"",
+ *(char *)data);
+ break;
+ case BTF_INT_BOOL:
+ jsonw_bool(jw, *(bool *)data);
+ break;
+ default:
+ /* shouldn't happen */
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int btf_dumper_struct(const struct btf_dumper *d, __u32 type_id,
+ const void *data)
+{
+ const struct btf_type *t;
+ struct btf_member *m;
+ const void *data_off;
+ int kind_flag;
+ int ret = 0;
+ int i, vlen;
+
+ t = btf__type_by_id(d->btf, type_id);
+ if (!t)
+ return -EINVAL;
+
+ kind_flag = BTF_INFO_KFLAG(t->info);
+ vlen = BTF_INFO_VLEN(t->info);
+ jsonw_start_object(d->jw);
+ m = (struct btf_member *)(t + 1);
+
+ for (i = 0; i < vlen; i++) {
+ __u32 bit_offset = m[i].offset;
+ __u32 bitfield_size = 0;
+
+ if (kind_flag) {
+ bitfield_size = BTF_MEMBER_BITFIELD_SIZE(bit_offset);
+ bit_offset = BTF_MEMBER_BIT_OFFSET(bit_offset);
+ }
+
+ jsonw_name(d->jw, btf__name_by_offset(d->btf, m[i].name_off));
+ data_off = data + BITS_ROUNDDOWN_BYTES(bit_offset);
+ if (bitfield_size) {
+ btf_dumper_bitfield(bitfield_size,
+ BITS_PER_BYTE_MASKED(bit_offset),
+ data_off, d->jw, d->is_plain_text);
+ } else {
+ ret = btf_dumper_do_type(d, m[i].type,
+ BITS_PER_BYTE_MASKED(bit_offset),
+ data_off);
+ if (ret)
+ break;
+ }
+ }
+
+ jsonw_end_object(d->jw);
+
+ return ret;
+}
+
+static int btf_dumper_var(const struct btf_dumper *d, __u32 type_id,
+ __u8 bit_offset, const void *data)
+{
+ const struct btf_type *t = btf__type_by_id(d->btf, type_id);
+ int ret;
+
+ jsonw_start_object(d->jw);
+ jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off));
+ ret = btf_dumper_do_type(d, t->type, bit_offset, data);
+ jsonw_end_object(d->jw);
+
+ return ret;
+}
+
+static int btf_dumper_datasec(const struct btf_dumper *d, __u32 type_id,
+ const void *data)
+{
+ struct btf_var_secinfo *vsi;
+ const struct btf_type *t;
+ int ret = 0, i, vlen;
+
+ t = btf__type_by_id(d->btf, type_id);
+ if (!t)
+ return -EINVAL;
+
+ vlen = BTF_INFO_VLEN(t->info);
+ vsi = (struct btf_var_secinfo *)(t + 1);
+
+ jsonw_start_object(d->jw);
+ jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off));
+ jsonw_start_array(d->jw);
+ for (i = 0; i < vlen; i++) {
+ ret = btf_dumper_do_type(d, vsi[i].type, 0, data + vsi[i].offset);
+ if (ret)
+ break;
+ }
+ jsonw_end_array(d->jw);
+ jsonw_end_object(d->jw);
+
+ return ret;
+}
+
+static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
+ __u8 bit_offset, const void *data)
+{
+ const struct btf_type *t = btf__type_by_id(d->btf, type_id);
+
+ switch (BTF_INFO_KIND(t->info)) {
+ case BTF_KIND_INT:
+ return btf_dumper_int(t, bit_offset, data, d->jw,
+ d->is_plain_text);
+ case BTF_KIND_STRUCT:
+ case BTF_KIND_UNION:
+ return btf_dumper_struct(d, type_id, data);
+ case BTF_KIND_ARRAY:
+ return btf_dumper_array(d, type_id, data);
+ case BTF_KIND_ENUM:
+ return btf_dumper_enum(d, t, data);
+ case BTF_KIND_PTR:
+ btf_dumper_ptr(d, t, data);
+ return 0;
+ case BTF_KIND_UNKN:
+ jsonw_printf(d->jw, "(unknown)");
+ return 0;
+ case BTF_KIND_FWD:
+ /* map key or value can't be forward */
+ jsonw_printf(d->jw, "(fwd-kind-invalid)");
+ return -EINVAL;
+ case BTF_KIND_TYPEDEF:
+ case BTF_KIND_VOLATILE:
+ case BTF_KIND_CONST:
+ case BTF_KIND_RESTRICT:
+ return btf_dumper_modifier(d, type_id, bit_offset, data);
+ case BTF_KIND_VAR:
+ return btf_dumper_var(d, type_id, bit_offset, data);
+ case BTF_KIND_DATASEC:
+ return btf_dumper_datasec(d, type_id, data);
+ default:
+ jsonw_printf(d->jw, "(unsupported-kind");
+ return -EINVAL;
+ }
+}
+
+int btf_dumper_type(const struct btf_dumper *d, __u32 type_id,
+ const void *data)
+{
+ return btf_dumper_do_type(d, type_id, 0, data);
+}
+
+#define BTF_PRINT_ARG(...) \
+ do { \
+ pos += snprintf(func_sig + pos, size - pos, \
+ __VA_ARGS__); \
+ if (pos >= size) \
+ return -1; \
+ } while (0)
+#define BTF_PRINT_TYPE(type) \
+ do { \
+ pos = __btf_dumper_type_only(btf, type, func_sig, \
+ pos, size); \
+ if (pos == -1) \
+ return -1; \
+ } while (0)
+
+static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id,
+ char *func_sig, int pos, int size)
+{
+ const struct btf_type *proto_type;
+ const struct btf_array *array;
+ const struct btf_var *var;
+ const struct btf_type *t;
+
+ if (!type_id) {
+ BTF_PRINT_ARG("void ");
+ return pos;
+ }
+
+ t = btf__type_by_id(btf, type_id);
+
+ switch (BTF_INFO_KIND(t->info)) {
+ case BTF_KIND_INT:
+ case BTF_KIND_TYPEDEF:
+ BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_STRUCT:
+ BTF_PRINT_ARG("struct %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_UNION:
+ BTF_PRINT_ARG("union %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_ENUM:
+ BTF_PRINT_ARG("enum %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_ARRAY:
+ array = (struct btf_array *)(t + 1);
+ BTF_PRINT_TYPE(array->type);
+ BTF_PRINT_ARG("[%d]", array->nelems);
+ break;
+ case BTF_KIND_PTR:
+ BTF_PRINT_TYPE(t->type);
+ BTF_PRINT_ARG("* ");
+ break;
+ case BTF_KIND_FWD:
+ BTF_PRINT_ARG("%s %s ",
+ BTF_INFO_KFLAG(t->info) ? "union" : "struct",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_VOLATILE:
+ BTF_PRINT_ARG("volatile ");
+ BTF_PRINT_TYPE(t->type);
+ break;
+ case BTF_KIND_CONST:
+ BTF_PRINT_ARG("const ");
+ BTF_PRINT_TYPE(t->type);
+ break;
+ case BTF_KIND_RESTRICT:
+ BTF_PRINT_ARG("restrict ");
+ BTF_PRINT_TYPE(t->type);
+ break;
+ case BTF_KIND_FUNC_PROTO:
+ pos = btf_dump_func(btf, func_sig, t, NULL, pos, size);
+ if (pos == -1)
+ return -1;
+ break;
+ case BTF_KIND_FUNC:
+ proto_type = btf__type_by_id(btf, t->type);
+ pos = btf_dump_func(btf, func_sig, proto_type, t, pos, size);
+ if (pos == -1)
+ return -1;
+ break;
+ case BTF_KIND_VAR:
+ var = (struct btf_var *)(t + 1);
+ if (var->linkage == BTF_VAR_STATIC)
+ BTF_PRINT_ARG("static ");
+ BTF_PRINT_TYPE(t->type);
+ BTF_PRINT_ARG(" %s",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_DATASEC:
+ BTF_PRINT_ARG("section (\"%s\") ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_UNKN:
+ default:
+ return -1;
+ }
+
+ return pos;
+}
+
+static int btf_dump_func(const struct btf *btf, char *func_sig,
+ const struct btf_type *func_proto,
+ const struct btf_type *func, int pos, int size)
+{
+ int i, vlen;
+
+ BTF_PRINT_TYPE(func_proto->type);
+ if (func)
+ BTF_PRINT_ARG("%s(", btf__name_by_offset(btf, func->name_off));
+ else
+ BTF_PRINT_ARG("(");
+ vlen = BTF_INFO_VLEN(func_proto->info);
+ for (i = 0; i < vlen; i++) {
+ struct btf_param *arg = &((struct btf_param *)(func_proto + 1))[i];
+
+ if (i)
+ BTF_PRINT_ARG(", ");
+ if (arg->type) {
+ BTF_PRINT_TYPE(arg->type);
+ if (arg->name_off)
+ BTF_PRINT_ARG("%s",
+ btf__name_by_offset(btf, arg->name_off));
+ else if (pos && func_sig[pos - 1] == ' ')
+ /* Remove unnecessary space for
+ * FUNC_PROTO that does not have
+ * arg->name_off
+ */
+ func_sig[--pos] = '\0';
+ } else {
+ BTF_PRINT_ARG("...");
+ }
+ }
+ BTF_PRINT_ARG(")");
+
+ return pos;
+}
+
+void btf_dumper_type_only(const struct btf *btf, __u32 type_id, char *func_sig,
+ int size)
+{
+ int err;
+
+ func_sig[0] = '\0';
+ if (!btf)
+ return;
+
+ err = __btf_dumper_type_only(btf, type_id, func_sig, 0, size);
+ if (err < 0)
+ func_sig[0] = '\0';
+}
+
+static const char *ltrim(const char *s)
+{
+ while (isspace(*s))
+ s++;
+
+ return s;
+}
+
+void btf_dump_linfo_plain(const struct btf *btf,
+ const struct bpf_line_info *linfo,
+ const char *prefix, bool linum)
+{
+ const char *line = btf__name_by_offset(btf, linfo->line_off);
+
+ if (!line)
+ return;
+ line = ltrim(line);
+
+ if (!prefix)
+ prefix = "";
+
+ if (linum) {
+ const char *file = btf__name_by_offset(btf, linfo->file_name_off);
+
+ /* More forgiving on file because linum option is
+ * expected to provide more info than the already
+ * available src line.
+ */
+ if (!file)
+ file = "";
+
+ printf("%s%s [file:%s line_num:%u line_col:%u]\n",
+ prefix, line, file,
+ BPF_LINE_INFO_LINE_NUM(linfo->line_col),
+ BPF_LINE_INFO_LINE_COL(linfo->line_col));
+ } else {
+ printf("%s%s\n", prefix, line);
+ }
+}
+
+void btf_dump_linfo_json(const struct btf *btf,
+ const struct bpf_line_info *linfo, bool linum)
+{
+ const char *line = btf__name_by_offset(btf, linfo->line_off);
+
+ if (line)
+ jsonw_string_field(json_wtr, "src", ltrim(line));
+
+ if (linum) {
+ const char *file = btf__name_by_offset(btf, linfo->file_name_off);
+
+ if (file)
+ jsonw_string_field(json_wtr, "file", file);
+
+ if (BPF_LINE_INFO_LINE_NUM(linfo->line_col))
+ jsonw_int_field(json_wtr, "line_num",
+ BPF_LINE_INFO_LINE_NUM(linfo->line_col));
+
+ if (BPF_LINE_INFO_LINE_COL(linfo->line_col))
+ jsonw_int_field(json_wtr, "line_col",
+ BPF_LINE_INFO_LINE_COL(linfo->line_col));
+ }
+}