cpptrace/src/symbols/symbols_with_libdwarf.cpp

987 lines
38 KiB
C++

#ifdef CPPTRACE_GET_SYMBOLS_WITH_LIBDWARF
#include <cpptrace/cpptrace.hpp>
#include "symbols.hpp"
#include "../platform/common.hpp"
#include "../platform/program_name.hpp"
#include "../platform/object.hpp"
#include <cassert>
#include <cstdint>
#include <cstdio>
#include <functional>
#include <memory>
#include <mutex>
#include <type_traits>
#include <vector>
#include <libdwarf.h>
#include <dwarf.h>
#if IS_APPLE
#include <libgen.h>
#endif
// some stuff is based on https://github.com/davea42/libdwarf-addr2line/blob/master/addr2line.c, mainly line handling
// then much expanded for symbols and efficiency
// dwarf5_ranges and dwarf4_ranges utility functions are taken from there directly, also pc_in_die
// TODO
// Inlined calls
// Memoizing / lazy loading
// More utils to clean this up, some wrapper for unique_ptr
// Ensure memory is being cleaned up properly
// Efficiency tricks
// Implementation cleanup
// Properly get the image base
#define DW_PR_DUx "llx"
#define DW_PR_DUu "llu"
static int dwarf5_ranges(Dwarf_Die cu_die, Dwarf_Addr *lowest, Dwarf_Addr *highest) {
Dwarf_Unsigned offset = 0;
Dwarf_Attribute attr = 0;
Dwarf_Half attrform = 0;
Dwarf_Unsigned i = 0;
int res = 0;
res = dwarf_attr(cu_die, DW_AT_ranges, &attr, nullptr);
if(res != DW_DLV_OK) {
return res;
}
if(dwarf_global_formref(attr, &offset, nullptr) == DW_DLV_OK) {
Dwarf_Unsigned rlesetoffset = 0;
Dwarf_Unsigned rnglists_count = 0;
Dwarf_Rnglists_Head head = 0;
dwarf_whatform(attr, &attrform, nullptr);
/* offset is in .debug_rnglists */
res = dwarf_rnglists_get_rle_head(
attr,
attrform,offset,
&head,
&rnglists_count,
&rlesetoffset,
nullptr
);
if(res != DW_DLV_OK) {
/* ASSERT: is DW_DLV_NO_ENTRY */
dwarf_dealloc_attribute(attr);
return res;
}
for( ; i < rnglists_count; ++i) {
unsigned entrylen = 0;
unsigned rle_val = 0;
Dwarf_Unsigned raw1 = 0;
Dwarf_Unsigned raw2 = 0;
Dwarf_Bool unavail = 0;
Dwarf_Unsigned cooked1 = 0;
Dwarf_Unsigned cooked2 = 0;
res = dwarf_get_rnglists_entry_fields_a(
head,
i,
&entrylen,
&rle_val,
&raw1,
&raw2,
&unavail,
&cooked1,
&cooked2,
nullptr
);
if(res != DW_DLV_OK) {
/* ASSERT: is DW_DLV_NO_ENTRY */
continue;
}
if(unavail) {
continue;
}
switch(rle_val) {
case DW_RLE_end_of_list:
case DW_RLE_base_address:
case DW_RLE_base_addressx:
/* These are accounted for already */
break;
case DW_RLE_offset_pair:
case DW_RLE_startx_endx:
case DW_RLE_start_end:
case DW_RLE_startx_length:
case DW_RLE_start_length:
if(cooked1 < *lowest) {
*lowest = cooked1;
}
if(cooked2 > *highest) {
*highest = cooked2;
}
default:
/* Something is wrong. */
break;
}
}
dwarf_dealloc_rnglists_head(head);
}
dwarf_dealloc_attribute(attr);
return DW_DLV_OK;
}
static int dwarf4_ranges(
Dwarf_Debug dbg,
Dwarf_Die cu_die,
Dwarf_Addr cu_lowpc,
Dwarf_Addr *lowest,
Dwarf_Addr *highest
) {
Dwarf_Unsigned offset;
Dwarf_Attribute attr = 0;
int res = 0;
res = dwarf_attr(cu_die, DW_AT_ranges, &attr, nullptr);
if(res != DW_DLV_OK) {
return res;
}
if(dwarf_global_formref(attr, &offset, nullptr) == DW_DLV_OK) {
Dwarf_Signed count = 0;
Dwarf_Ranges *ranges = 0;
Dwarf_Addr baseaddr = 0;
if(cu_lowpc != 0xffffffffffffffff) {
baseaddr = cu_lowpc;
}
res = dwarf_get_ranges_b(
dbg,
offset,
cu_die,
nullptr,
&ranges,
&count,
nullptr,
nullptr
);
for(int i = 0; i < count; i++) {
Dwarf_Ranges *cur = ranges + i;
if(cur->dwr_type == DW_RANGES_ENTRY) {
Dwarf_Addr rng_lowpc, rng_highpc;
rng_lowpc = baseaddr + cur->dwr_addr1;
rng_highpc = baseaddr + cur->dwr_addr2;
if(rng_lowpc < *lowest) {
*lowest = rng_lowpc;
}
if(rng_highpc > *highest) {
*highest = rng_highpc;
}
} else if(cur->dwr_type ==
DW_RANGES_ADDRESS_SELECTION) {
baseaddr = cur->dwr_addr2;
} else { // DW_RANGES_END
baseaddr = cu_lowpc;
}
}
dwarf_dealloc_ranges(dbg, ranges, count);
}
dwarf_dealloc_attribute(attr);
return DW_DLV_OK;
}
namespace cpptrace {
namespace detail {
namespace libdwarf {
// printbugging as we go
constexpr bool dump_dwarf = false;
constexpr bool trace_dwarf = false;
static void err_handler(Dwarf_Error err, Dwarf_Ptr errarg) {
printf("libdwarf error reading %s: %lu %s\n", "xx", (unsigned long)dwarf_errno(err), dwarf_errmsg(err));
if(errarg) {
printf("Error: errarg is nonnull but it should be null\n");
}
printf("Giving up");
exit(1);
}
static void print_line(Dwarf_Debug dbg, Dwarf_Line line, Dwarf_Addr pc, stacktrace_frame& frame) {
char what[] = "??";
char * linesrc = what;
Dwarf_Unsigned lineno = 0;
(void)pc;
if(line) {
/* These never return DW_DLV_NO_ENTRY */
dwarf_linesrc(line, &linesrc, nullptr);
dwarf_lineno(line, &lineno, nullptr);
}
if(dump_dwarf) {
printf("%s:%" DW_PR_DUu "\n", linesrc, lineno);
}
frame.line = static_cast<uint_least32_t>(lineno);
frame.filename = linesrc;
if(line) {
dwarf_dealloc(dbg, linesrc, DW_DLA_STRING);
}
}
static Dwarf_Bool pc_in_die(Dwarf_Debug dbg, Dwarf_Die die,int version, Dwarf_Addr pc) {
int ret;
Dwarf_Addr cu_lowpc = 0xffffffffffffffff;
Dwarf_Addr cu_highpc = 0;
enum Dwarf_Form_Class highpc_cls;
Dwarf_Addr lowest = 0xffffffffffffffff;
Dwarf_Addr highest = 0;
ret = dwarf_lowpc(die, &cu_lowpc, nullptr);
if(ret == DW_DLV_OK) {
if(pc == cu_lowpc) {
return true;
}
ret = dwarf_highpc_b(die, &cu_highpc,
nullptr, &highpc_cls, nullptr);
if(ret == DW_DLV_OK) {
if(highpc_cls == DW_FORM_CLASS_CONSTANT) {
cu_highpc += cu_lowpc;
}
//fprintf(stderr, "low: %llx high: %llx pc: %llx\n", cu_lowpc, cu_highpc, pc);
if(pc >= cu_lowpc && pc < cu_highpc) {
return true;
}
}
}
if(version >= 5) {
ret = dwarf5_ranges(die,
&lowest,&highest);
} else {
ret = dwarf4_ranges(dbg,die,cu_lowpc,
&lowest,&highest);
}
//fprintf(stderr, "low: %llu high: %llu\n", lowest, highest);
if(pc >= lowest && pc < highest) {
return true;
}
return false;
}
static_assert(std::is_pointer<Dwarf_Die>::value, "Dwarf_Die not a pointer");
static_assert(std::is_pointer<Dwarf_Debug>::value, "Dwarf_Debug not a pointer");
struct die_object {
Dwarf_Debug dbg = nullptr;
Dwarf_Die die = nullptr;
die_object(Dwarf_Debug dbg, Dwarf_Die die) : dbg(dbg), die(die) {}
~die_object() {
if(die) {
dwarf_dealloc(dbg, die, DW_DLA_DIE);
}
}
die_object(const die_object&) = delete;
die_object& operator=(const die_object&) = delete;
die_object(die_object&& other) : dbg(other.dbg), die(other.die) {
other.die = nullptr;
}
die_object& operator=(die_object&& other) {
dbg = other.dbg;
die = other.die;
other.die = nullptr;
return *this;
}
die_object get_child() const {
Dwarf_Die child = nullptr;
int ret = dwarf_child(
die,
&child,
nullptr
);
if(ret == DW_DLV_OK) {
return die_object(dbg, child);
} else if(ret == DW_DLV_NO_ENTRY) {
return die_object(dbg, 0);
} else {
fprintf(stderr, "Error\n");
exit(1);
}
}
die_object get_sibling() const {
Dwarf_Die sibling = 0;
int ret = dwarf_siblingof_b(dbg, die, true, &sibling, nullptr);
if(ret == DW_DLV_OK) {
return die_object(dbg, sibling);
} else if(ret == DW_DLV_NO_ENTRY) {
return die_object(dbg, 0);
} else {
fprintf(stderr, "Error\n");
exit(1);
}
}
operator bool() const {
return die != nullptr;
}
Dwarf_Die get() const {
return die;
}
std::string get_name() const {
char* name;
int ret = dwarf_diename(die, &name, nullptr);
std::string str;
if(ret != DW_DLV_NO_ENTRY) {
str = name;
dwarf_dealloc(dbg, name, DW_DLA_STRING);
}
return name;
}
optional<std::string> get_string_attribute(Dwarf_Half dw_attrnum) const {
Dwarf_Attribute attr;
int ret = dwarf_attr(die, dw_attrnum, &attr, nullptr);
if(ret == DW_DLV_OK) {
char* raw_str;
std::string str;
ret = dwarf_formstring(attr, &raw_str, nullptr);
assert(ret == DW_DLV_OK);
str = raw_str;
dwarf_dealloc(dbg, raw_str, DW_DLA_STRING);
dwarf_dealloc(dbg, attr, DW_DLA_ATTR);
return str;
} else {
return nullopt;
}
}
bool has_attr(Dwarf_Half dw_attrnum) const {
Dwarf_Attribute attr;
int ret = dwarf_attr(die, dw_attrnum, &attr, nullptr);
if(ret == DW_DLV_NO_ENTRY) {
return false;
} else if(ret == DW_DLV_OK) {
// TODO: Better impl that doesn't require allocation....?
dwarf_dealloc(dbg, attr, DW_DLA_ATTR);
return true;
} else {
fprintf(stderr, "Error\n");
exit(1);
}
}
Dwarf_Half get_tag() const {
Dwarf_Half tag = 0;
dwarf_tag(die, &tag, nullptr);
return tag;
}
const char* get_tag_name() const {
const char* tag_name;
dwarf_get_TAG_name(get_tag(), &tag_name);
return tag_name;
}
Dwarf_Off get_global_offset() const {
Dwarf_Off off;
int ret = dwarf_dieoffset(die, &off, nullptr);
assert(ret == DW_DLV_OK);
return off;
}
};
void walk_die_list(
Dwarf_Debug dbg,
const die_object& die,
std::function<void(Dwarf_Debug, const die_object&)> fn
) {
fn(dbg, die);
die_object current = die.get_sibling();
while(true) {
if(!current) {
if(dump_dwarf) {
fprintf(stderr, "End walk_die_list\n");
}
return;
}
fn(dbg, current);
current = current.get_sibling();
}
}
void walk_die_list_recursive(
Dwarf_Debug dbg,
const die_object& die,
std::function<void(Dwarf_Debug, const die_object&)> fn
) {
walk_die_list(
dbg,
die,
[&fn](Dwarf_Debug dbg, const die_object& die) {
auto child = die.get_child();
if(child) {
walk_die_list_recursive(dbg, child, fn);
}
fn(dbg, die);
}
);
}
die_object get_type_die(Dwarf_Debug dbg, const die_object& die) {
Dwarf_Off type_offset;
Dwarf_Bool is_info;
int ret = dwarf_dietype_offset(die.get(), &type_offset, &is_info, nullptr);
if(ret == DW_DLV_OK) {
Dwarf_Die type_die;
ret = dwarf_offdie_b(
dbg,
type_offset,
is_info,
&type_die,
nullptr
);
if(ret == DW_DLV_OK) {
return die_object(dbg, type_die);
} else {
fprintf(stderr, "Error\n");
exit(1);
}
} else {
fprintf(stderr, "no type offset??\n");
}
return die_object(dbg, nullptr);
}
bool has_type(Dwarf_Debug dbg, const die_object& die) {
Dwarf_Attribute attr;
int ret = dwarf_attr(die.get(), DW_AT_type, &attr, nullptr);
if(ret == DW_DLV_NO_ENTRY) {
return false;
} else if(ret == DW_DLV_OK) {
dwarf_dealloc(dbg, attr, DW_DLA_ATTR);
return true;
} else {
fprintf(stderr, "Error\n");
exit(1);
}
}
struct type_result {
std::string base;
std::string extent;
std::string get_type() {
return base + extent;
}
};
// TODO: ::*, namespace lookup, arrays
// DW_TAG_namespace
const char* tag_to_keyword(Dwarf_Half tag) {
switch(tag) {
case DW_TAG_atomic_type:
return "_Atomic";
case DW_TAG_const_type:
return "const";
case DW_TAG_volatile_type:
return "volatile";
case DW_TAG_restrict_type:
return "restrict";
default:
{
const char* tag_name = nullptr;
dwarf_get_TAG_name(tag, &tag_name);
fprintf(stderr, "tag_to_keyword unknown tag %s\n", tag_name);
exit(1);
}
}
}
const char* tag_to_ptr_ref(Dwarf_Half tag) {
switch(tag) {
case DW_TAG_pointer_type:
return "*";
case DW_TAG_ptr_to_member_type:
return "::*"; // TODO
case DW_TAG_reference_type:
return "&";
case DW_TAG_rvalue_reference_type:
return "&&";
default:
{
const char* tag_name = nullptr;
dwarf_get_TAG_name(tag, &tag_name);
fprintf(stderr, "tag_to_ptr_ref unknown tag %s\n", tag_name);
exit(1);
}
}
}
/*std::string resolve_type(Dwarf_Debug dbg, const die_object& die, std::string build = "");
std::string get_array_extents(Dwarf_Debug dbg, const die_object& die) {
assert(die.get_tag() == DW_TAG_array_type);
std::string extents = "";
walk_die_list(dbg, die.get_child(), [&extents](Dwarf_Debug dbg, const die_object& subrange) {
if(subrange.get_tag() == DW_TAG_subrange_type) {
Dwarf_Attribute attr = 0;
int res = 0;
res = dwarf_attr(subrange.get(), DW_AT_upper_bound, &attr, nullptr);
if(res != DW_DLV_OK) {
fprintf(stderr, "Error\n");
return;
}
Dwarf_Half form;
res = dwarf_whatform(attr, &form, nullptr);
if(res != DW_DLV_OK) {
fprintf(stderr, "Error\n");
return;
}
//fprintf(stderr, "form: %d\n", form);
Dwarf_Unsigned val;
res = dwarf_formudata(attr, &val, nullptr);
if(res != DW_DLV_OK) {
fprintf(stderr, "Error\n");
return;
}
extents += "[" + std::to_string(val + 1) + "]";
dwarf_dealloc_attribute(attr);
} else {
fprintf(stderr, "unknown tag %s\n", subrange.get_tag_name());
}
});
return extents;
}
std::string get_parameters(Dwarf_Debug dbg, const die_object& die) {
assert(die.get_tag() == DW_TAG_subroutine_type);
std::vector<std::string> params;
walk_die_list(dbg, die.get_child(), [&params](Dwarf_Debug dbg, const die_object& die) {
if(die.get_tag() == DW_TAG_formal_parameter) {
// TODO: Ignore DW_AT_artificial
params.push_back(resolve_type(dbg, get_type_die(dbg, die)));
}
});
return "(" + join(params, ", ") + ")";
}
std::string resolve_type(Dwarf_Debug dbg, const die_object& die, std::string build) {
switch(auto tag = die.get_tag()) {
case DW_TAG_base_type:
case DW_TAG_class_type:
case DW_TAG_structure_type:
case DW_TAG_union_type:
case DW_TAG_enumeration_type:
return die.get_name() + build;
case DW_TAG_typedef:
return resolve_type(dbg, get_type_die(dbg, die));
//case DW_TAG_subroutine_type:
// {
// // If there's no DW_AT_type then it's a void
// std::vector<std::string> params;
// // TODO: Code duplication with retrieve_symbol_for_subprogram?
// walk_die_list(dbg, die.get_child(), [&params] (Dwarf_Debug dbg, const die_object& die) {
// if(die.get_tag() == DW_TAG_formal_parameter) {
// // TODO: Ignore DW_AT_artificial
// params.push_back(resolve_type(dbg, get_type_die(dbg, die)));
// }
// });
// if(!has_type(dbg, die)) {
// return "void" + (build.empty() ? "" : "(" + build + ")") + "(" + join(params, ", ") + ")";
// } else {
// // resolving return type, building on build
// return resolve_type(
// dbg, get_type_die(dbg, die),
// (build.empty() ? "" : "(" + build + ")")
// + "("
// + join(params, ", ")
// + ")"
// );
// }
// }
//case DW_TAG_array_type:
// return resolve_type(dbg, get_type_die(dbg, die), (build.empty() ? "" : "(" + build + ")") + "[" + "x" + "]");
case DW_TAG_pointer_type:
case DW_TAG_reference_type:
case DW_TAG_rvalue_reference_type:
case DW_TAG_ptr_to_member_type:
{
const auto child = get_type_die(dbg, die); // AST child, rather than dwarf child
const auto child_tag = child.get_tag();
switch(child_tag) {
case DW_TAG_subroutine_type:
if(!has_type(dbg, child)) {
return "void(" + std::string(tag_to_ptr_ref(tag)) + build + ")" + get_parameters(dbg, child);
} else {
return resolve_type(
dbg,
get_type_die(dbg, child),
"(" + std::string(tag_to_ptr_ref(tag)) + build + ")" + get_parameters(dbg, child)
);
}
case DW_TAG_array_type:
return resolve_type(
dbg,
get_type_die(dbg, child),
"(" + std::string(tag_to_ptr_ref(tag)) + build + ")" + get_array_extents(dbg, child)
);
default:
if(build.empty()) {
return resolve_type(dbg, get_type_die(dbg, die), tag_to_ptr_ref(tag));
} else {
return resolve_type(
dbg,
get_type_die(dbg, die),
std::string(tag_to_ptr_ref(tag)) + " " + build
);
}
}
}
case DW_TAG_const_type:
case DW_TAG_atomic_type:
case DW_TAG_volatile_type:
case DW_TAG_restrict_type:
{
const auto child = get_type_die(dbg, die); // AST child, rather than dwarf child
const auto child_tag = child.get_tag();
switch(child_tag) {
case DW_TAG_base_type:
case DW_TAG_class_type:
case DW_TAG_typedef:
return std::string(tag_to_keyword(tag))
+ " "
+ resolve_type(dbg, get_type_die(dbg, die), build);
default:
return resolve_type(
dbg,
get_type_die(dbg, die),
std::string(tag_to_keyword(tag)) + " " + build
);
}
}
default:
{
fprintf(stderr, "unknown tag %s\n", die.get_tag_name());
exit(1);
}
}
return {"<unknown>", "<unknown>"};
}*/
bool is_mangled_name(const std::string& name) {
return name.find("_Z") || name.find("?h@@");
}
void retrieve_symbol_for_subprogram(
Dwarf_Debug dbg,
const die_object& die,
Dwarf_Addr pc,
Dwarf_Half dwversion,
stacktrace_frame& frame
) {
assert(die.get_tag() == DW_TAG_subprogram);
optional<std::string> name;
if(auto linkage_name = die.get_string_attribute(DW_AT_linkage_name)) {
name = std::move(linkage_name);
} else if(auto linkage_name = die.get_string_attribute(DW_AT_MIPS_linkage_name)) {
name = std::move(linkage_name);
} else if(auto linkage_name = die.get_string_attribute(DW_AT_name)) {
name = std::move(linkage_name);
}
if(name) {
frame.symbol = std::move(name).unwrap();
}
// TODO: Handle namespaces
// TODO: Disabled for now
/*std::string name = die.get_name();
std::vector<std::string> params;
auto child = die.get_child();
if(child) {
walk_die_list_recursive(
dbg,
child,
[pc, dwversion, &frame, &params] (Dwarf_Debug dbg, const die_object& die) {
if(die.get_tag() == DW_TAG_formal_parameter) {
// TODO: Ignore DW_AT_artificial
params.push_back(resolve_type(dbg, get_type_die(dbg, die)));
}
}
);
} else {
fprintf(stderr, "no child %s\n", name.c_str());
}
frame.symbol = name + "(" + join(params, ", ") + ")";*/
}
void retrieve_symbol(
Dwarf_Debug dbg,
const die_object& die,
Dwarf_Addr pc,
Dwarf_Half dwversion,
stacktrace_frame& frame
) {
walk_die_list(
dbg,
die,
[pc, dwversion, &frame] (Dwarf_Debug dbg, const die_object& die) {
int ret;
if(dump_dwarf) {
fprintf(
stderr,
"-------------> %d %s %s\n",
dwversion,
die.get_tag_name(),
die.get_name().c_str()
);
}
if(!pc_in_die(dbg, die.get(), dwversion, pc)) {
if(dump_dwarf) {
fprintf(stderr, "pc not in die\n");
}
} else {
if(trace_dwarf) {
fprintf(stderr, "pc in die %08llx %s\n", die.get_global_offset(), die.get_tag_name());
}
if(dump_dwarf) {
fprintf(stderr, "pc in die <-----------------------------------\n");
}
if(die.get_tag() == DW_TAG_subprogram) {
retrieve_symbol_for_subprogram(dbg, die, pc, dwversion, frame);
}
auto child = die.get_child();
if(child) {
retrieve_symbol(dbg, child, pc, dwversion, frame);
} else {
if(dump_dwarf) {
fprintf(stderr, "(no child)\n");
}
}
}
}
);
}
void retrieve_line_info(
Dwarf_Debug dbg,
const die_object& die,
Dwarf_Addr pc,
Dwarf_Half dwversion,
stacktrace_frame& frame
) {
Dwarf_Unsigned version;
Dwarf_Small table_count;
Dwarf_Line_Context ctxt;
Dwarf_Bool is_found = false;
(void)dwversion;
int ret = dwarf_srclines_b(
die.get(),
&version,
&table_count,
&ctxt,
nullptr
);
if(ret == DW_DLV_NO_ENTRY) {
fprintf(stderr, "dwarf_srclines_b error\n");
return;
}
if(table_count == 1) {
Dwarf_Line *linebuf = 0;
Dwarf_Signed linecount = 0;
Dwarf_Addr prev_lineaddr = 0;
dwarf_srclines_from_linecontext(ctxt, &linebuf,
&linecount, nullptr);
Dwarf_Line prev_line = 0;
for(int i = 0; i < linecount; i++) {
Dwarf_Line line = linebuf[i];
Dwarf_Addr lineaddr = 0;
dwarf_lineaddr(line, &lineaddr, nullptr);
if(pc == lineaddr) {
/* Print the last line entry containing current pc. */
Dwarf_Line last_pc_line = line;
for(int j = i + 1; j < linecount; j++) {
Dwarf_Line j_line = linebuf[j];
dwarf_lineaddr(j_line, &lineaddr, nullptr);
if(pc == lineaddr) {
last_pc_line = j_line;
}
}
is_found = true;
print_line(dbg, last_pc_line, pc, frame);
break;
} else if(prev_line && pc > prev_lineaddr &&
pc < lineaddr) {
is_found = true;
print_line(dbg, prev_line, pc, frame);
break;
}
Dwarf_Bool is_lne;
dwarf_lineendsequence(line, &is_lne, nullptr);
if(is_lne) {
prev_line = 0;
} else {
prev_lineaddr = lineaddr;
prev_line = line;
}
}
}
dwarf_srclines_dealloc_b(ctxt);
}
void walk_compilation_units(Dwarf_Debug dbg, Dwarf_Addr pc, stacktrace_frame& frame) {
// 0 passed as the dieto the first call of dwarf_siblingof_b immediately after dwarf_next_cu_header_d to
// fetch the cu die
die_object cu_die(dbg, nullptr);
cu_die = cu_die.get_sibling();
if(!cu_die) {
if(dump_dwarf) {
fprintf(stderr, "End walk_compilation_units\n");
}
return;
}
walk_die_list(
dbg,
cu_die,
[&frame, pc] (Dwarf_Debug dbg, const die_object& cu_die) {
Dwarf_Half offset_size = 0;
Dwarf_Half dwversion = 0;
dwarf_get_version_of_die(cu_die.get(), &dwversion, &offset_size);
if(trace_dwarf) {
fprintf(stderr, "CU: %d %s\n", dwversion, cu_die.get_name().c_str());
}
/*auto child = cu_die.get_child();
if(child) {
walk_die_list_recursive(
dbg,
child,
[&frame, pc, dwversion] (Dwarf_Debug dbg, const die_object& cu_die) {
}
);
}*/
//walk_die(dbg, cu_die, pc, dwversion, false, frame);
if(pc_in_die(dbg, cu_die.get(), dwversion, pc)) {
retrieve_line_info(dbg, cu_die, pc, dwversion, frame);
retrieve_symbol(dbg, cu_die, pc, dwversion, frame);
}
}
);
}
void walk_dbg(Dwarf_Debug dbg, Dwarf_Addr pc, stacktrace_frame& frame) {
// libdwarf keeps track of where it is in the file, dwarf_next_cu_header_d is statefull
Dwarf_Unsigned next_cu_header;
Dwarf_Half header_cu_type;
while(true) {
int ret = dwarf_next_cu_header_d(
dbg,
true,
nullptr,
nullptr,
nullptr,
nullptr,
nullptr,
nullptr,
nullptr,
nullptr,
&next_cu_header,
&header_cu_type,
nullptr
);
if(ret == DW_DLV_NO_ENTRY) {
if(dump_dwarf) {
fprintf(stderr, "End walk_dbg\n");
}
return;
}
if(ret != DW_DLV_OK) {
fprintf(stderr, "Error\n");
return;
}
walk_compilation_units(dbg, pc, frame);
}
}
void lookup_pc(
const char* object,
Dwarf_Addr pc,
stacktrace_frame& frame
) {
if(dump_dwarf) {
fprintf(stderr, "%s\n", object);
fprintf(stderr, "%llx\n", pc);
}
Dwarf_Debug dbg;
Dwarf_Ptr errarg = 0;
auto ret = dwarf_init_path(
object,
nullptr,
0,
DW_GROUPNUMBER_ANY,
err_handler,
errarg,
&dbg,
nullptr
);
if(ret == DW_DLV_NO_ENTRY) {
// fail, no debug info
} else if(ret != DW_DLV_OK) {
fprintf(stderr, "Error\n");
} else {
walk_dbg(dbg, pc, frame);
}
dwarf_finish(dbg);
}
stacktrace_frame resolve_frame(const dlframe& frame_info) {
stacktrace_frame frame{};
frame.filename = frame_info.obj_path;
frame.symbol = frame_info.symbol;
frame.address = frame_info.raw_address;
std::string obj_path = frame_info.obj_path;
#if IS_APPLE
//std::string obj_path = frame_info.obj_path;
//char* dir = dirname(obj_path.data());
//std::string dsym =
if(directory_exists(obj_path + ".dSYM")) {
std::string obj_path_copy = frame_info.obj_path;
std::string base = basename(const_cast<char*>(obj_path_copy.data()));
obj_path += ".dSYM/Contents/Resources/DWARF/" + base;
}
#endif
if(trace_dwarf) {
fprintf(
stderr,
"%s %08lx %s\n",
obj_path.c_str(),
frame_info.obj_address,
frame_info.symbol.c_str()
);
}
lookup_pc(
obj_path.c_str(),
frame_info.obj_address,
frame
);
return frame;
}
std::vector<stacktrace_frame> resolve_frames(const std::vector<void*>& frames) {
std::vector<stacktrace_frame> trace;
trace.reserve(frames.size());
for(const auto& frame : get_frames_object_info(frames)) {
trace.push_back(resolve_frame(frame));
}
return trace;
}
}
}
}
#endif