#include "debug_utils.h"

#include "env-inl.h"

#include "util-inl.h"

#ifdef __POSIX__

#if defined(__linux__)

#include <features.h>

#endif

#if defined(__linux__) && !defined(__GLIBC__) || \

defined(__UCLIBC__) || \

defined(_AIX)

#define HAVE_EXECINFO_H 0

#else

#define HAVE_EXECINFO_H 1

#endif

#if HAVE_EXECINFO_H

#include <cxxabi.h>

#include <dlfcn.h>

#include <execinfo.h>

#include <unistd.h>

#include <sys/mman.h>

#include <cstdio>

#endif

#endif // __POSIX__

#if defined(__linux__) || defined(__sun) || defined(__FreeBSD__)

#include <link.h>

#endif // (__linux__) || defined(__sun) || defined(__FreeBSD__)

#ifdef __APPLE__

#include <mach-o/dyld.h> // _dyld_get_image_name()

#endif // __APPLE__

#ifdef _AIX

#include <sys/ldr.h> // ld_info structure

#endif // _AIX

#ifdef _WIN32

#include <Lm.h>

#include <Windows.h>

#include <dbghelp.h>

#include <process.h>

#include <psapi.h>

#include <tchar.h>

#endif // _WIN32

namespace node {

#ifdef __POSIX__

#if HAVE_EXECINFO_H

class PosixSymbolDebuggingContext final : public NativeSymbolDebuggingContext {

public:

PosixSymbolDebuggingContext() : pagesize_(getpagesize()) { }

SymbolInfo LookupSymbol(void* address) override {

Dl_info info;

const bool have_info = dladdr(address, &info);

SymbolInfo ret;

if (!have_info)

return ret;

if (info.dli_sname != nullptr) {

if (char* demangled =

abi::__cxa_demangle(info.dli_sname, nullptr, nullptr, nullptr)) {

ret.name = demangled;

free(demangled);

} else {

ret.name = info.dli_sname;

}

}

if (info.dli_fname != nullptr) {

ret.filename = info.dli_fname;

}

return ret;

}

bool IsMapped(void* address) override {

void* page_aligned = reinterpret_cast<void*>(

reinterpret_cast<uintptr_t>(address) & ~(pagesize_ - 1));

return msync(page_aligned, pagesize_, MS_ASYNC) == 0;

}

int GetStackTrace(void** frames, int count) override {

return backtrace(frames, count);

}

private:

uintptr_t pagesize_;

};

std::unique_ptr<NativeSymbolDebuggingContext>

NativeSymbolDebuggingContext::New() {

return std::unique_ptr<NativeSymbolDebuggingContext>(

new PosixSymbolDebuggingContext());

}

#else // HAVE_EXECINFO_H

std::unique_ptr<NativeSymbolDebuggingContext>

NativeSymbolDebuggingContext::New() {

return std::unique_ptr<NativeSymbolDebuggingContext>(

new NativeSymbolDebuggingContext());

}

#endif // HAVE_EXECINFO_H

#else // __POSIX__

class Win32SymbolDebuggingContext final : public NativeSymbolDebuggingContext {

public:

Win32SymbolDebuggingContext() {

current_process_ = GetCurrentProcess();

USE(SymInitialize(current_process_, nullptr, true));

}

~Win32SymbolDebuggingContext() override {

USE(SymCleanup(current_process_));

}

using NameAndDisplacement = std::pair<std::string, DWORD64>;

NameAndDisplacement WrappedSymFromAddr(DWORD64 dwAddress) const {

// Refs: https://docs.microsoft.com/en-us/windows/desktop/Debug/retrieving-symbol-information-by-address

// Patches:

// Use `fprintf(stderr, ` instead of `printf`

// `sym.filename = pSymbol->Name` on success

// `current_process_` instead of `hProcess.

DWORD64 dwDisplacement = 0;

// Patch: made into arg - DWORD64 dwAddress = SOME_ADDRESS;

char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(TCHAR)];

const auto pSymbol = reinterpret_cast<PSYMBOL_INFO>(buffer);

pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);

pSymbol->MaxNameLen = MAX_SYM_NAME;

if (SymFromAddr(current_process_, dwAddress, &dwDisplacement, pSymbol)) {

// SymFromAddr returned success

return NameAndDisplacement(pSymbol->Name, dwDisplacement);

} else {

// SymFromAddr failed

const DWORD error = GetLastError(); // "eat" the error anyway

#ifdef DEBUG

fprintf(stderr, "SymFromAddr returned error : %lu\n", error);

#endif

}

// End MSDN code

return NameAndDisplacement();

}

SymbolInfo WrappedGetLine(DWORD64 dwAddress) const {

SymbolInfo sym{};

// Refs: https://docs.microsoft.com/en-us/windows/desktop/Debug/retrieving-symbol-information-by-address

// Patches:

// Use `fprintf(stderr, ` instead of `printf`.

// Assign values to `sym` on success.

// `current_process_` instead of `hProcess.

// Patch: made into arg - DWORD64 dwAddress;

DWORD dwDisplacement;

IMAGEHLP_LINE64 line;

SymSetOptions(SYMOPT_LOAD_LINES);

line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);

// Patch: made into arg - dwAddress = 0x1000000;

if (SymGetLineFromAddr64(current_process_, dwAddress,

&dwDisplacement, &line)) {

// SymGetLineFromAddr64 returned success

sym.filename = line.FileName;

sym.line = line.LineNumber;

} else {

// SymGetLineFromAddr64 failed

const DWORD error = GetLastError(); // "eat" the error anyway

#ifdef DEBUG

fprintf(stderr, "SymGetLineFromAddr64 returned error : %lu\n", error);

#endif

}

// End MSDN code

return sym;

}

// Fills the SymbolInfo::name of the io/out argument `sym`

std::string WrappedUnDecorateSymbolName(const char* name) const {

// Refs: https://docs.microsoft.com/en-us/windows/desktop/Debug/retrieving-undecorated-symbol-names

// Patches:

// Use `fprintf(stderr, ` instead of `printf`.

// return `szUndName` instead of `printf` on success

char szUndName[MAX_SYM_NAME];

if (UnDecorateSymbolName(name, szUndName, sizeof(szUndName),

UNDNAME_COMPLETE)) {

// UnDecorateSymbolName returned success

return szUndName;

} else {

// UnDecorateSymbolName failed

const DWORD error = GetLastError(); // "eat" the error anyway

#ifdef DEBUG

fprintf(stderr, "UnDecorateSymbolName returned error %lu\n", error);

#endif

}

return nullptr;

}

SymbolInfo LookupSymbol(void* address) override {

const DWORD64 dw_address = reinterpret_cast<DWORD64>(address);

SymbolInfo ret = WrappedGetLine(dw_address);

std::tie(ret.name, ret.dis) = WrappedSymFromAddr(dw_address);

if (!ret.name.empty()) {

ret.name = WrappedUnDecorateSymbolName(ret.name.c_str());

}

return ret;

}

bool IsMapped(void* address) override {

MEMORY_BASIC_INFORMATION info;

if (VirtualQuery(address, &info, sizeof(info)) != sizeof(info))

return false;

return info.State == MEM_COMMIT && info.Protect != 0;

}

int GetStackTrace(void** frames, int count) override {

return CaptureStackBackTrace(0, count, frames, nullptr);

}

Win32SymbolDebuggingContext(const Win32SymbolDebuggingContext&) = delete;

Win32SymbolDebuggingContext(Win32SymbolDebuggingContext&&) = delete;

Win32SymbolDebuggingContext operator=(const Win32SymbolDebuggingContext&)

= delete;

Win32SymbolDebuggingContext operator=(Win32SymbolDebuggingContext&&)

= delete;

private:

HANDLE current_process_;

};

std::unique_ptr<NativeSymbolDebuggingContext>

NativeSymbolDebuggingContext::New() {

return std::unique_ptr<NativeSymbolDebuggingContext>(

new Win32SymbolDebuggingContext());

}

#endif // __POSIX__

std::string NativeSymbolDebuggingContext::SymbolInfo::Display() const {

std::ostringstream oss;

oss << name;

if (dis != 0) {

oss << "+" << dis;

}

if (!filename.empty()) {

oss << " [" << filename << ']';

}

if (line != 0) {

oss << ":L" << line;

}

return oss.str();

}

void DumpBacktrace(FILE* fp) {

auto sym_ctx = NativeSymbolDebuggingContext::New();

void* frames[256];

const int size = sym_ctx->GetStackTrace(frames, arraysize(frames));

for (int i = 1; i < size; i += 1) {

void* frame = frames[i];

NativeSymbolDebuggingContext::SymbolInfo s = sym_ctx->LookupSymbol(frame);

fprintf(fp, "%2d: %p %s\n", i, frame, s.Display().c_str());

}

}

void CheckedUvLoopClose(uv_loop_t* loop) {

if (uv_loop_close(loop) == 0) return;

PrintLibuvHandleInformation(loop, stderr);

fflush(stderr);

// Finally, abort.

CHECK(0 && "uv_loop_close() while having open handles");

}

void PrintLibuvHandleInformation(uv_loop_t* loop, FILE* stream) {

struct Info {

std::unique_ptr<NativeSymbolDebuggingContext> ctx;

FILE* stream;

};

Info info { NativeSymbolDebuggingContext::New(), stream };

fprintf(stream, "uv loop at [%p] has %d active handles\n",

loop, loop->active_handles);

uv_walk(loop, [](uv_handle_t* handle, void* arg) {

Info* info = static_cast<Info*>(arg);

NativeSymbolDebuggingContext* sym_ctx = info->ctx.get();

FILE* stream = info->stream;

fprintf(stream, "[%p] %s\n", handle, uv_handle_type_name(handle->type));

void* close_cb = reinterpret_cast<void*>(handle->close_cb);

fprintf(stream, "\tClose callback: %p %s\n",

close_cb, sym_ctx->LookupSymbol(close_cb).Display().c_str());

fprintf(stream, "\tData: %p %s\n",

handle->data, sym_ctx->LookupSymbol(handle->data).Display().c_str());

// We are also interested in the first field of what `handle->data`

// points to, because for C++ code that is usually the virtual table pointer

// and gives us information about the exact kind of object we're looking at.

void* first_field = nullptr;

// `handle->data` might be any value, including `nullptr`, or something

// cast from a completely different type; therefore, check that it’s

// dereferencable first.

if (sym_ctx->IsMapped(handle->data))

first_field = *reinterpret_cast<void**>(handle->data);

if (first_field != nullptr) {

fprintf(stream, "\t(First field): %p %s\n",

first_field, sym_ctx->LookupSymbol(first_field).Display().c_str());

}

}, &info);

}

std::vector<std::string> NativeSymbolDebuggingContext::GetLoadedLibraries() {

std::vector<std::string> list;

#if defined(__linux__) || defined(__FreeBSD__)

dl_iterate_phdr(

[](struct dl_phdr_info* info, size_t size, void* data) {

auto list = static_cast<std::vector<std::string>*>(data);

if (*info->dlpi_name != '\0') {

list->push_back(info->dlpi_name);

}

return 0;

},

&list);

#elif __APPLE__

uint32_t i = 0;

for (const char* name = _dyld_get_image_name(i); name != nullptr;

name = _dyld_get_image_name(++i)) {

list.push_back(name);

}

#elif _AIX

// We can't tell in advance how large the buffer needs to be.

// Retry until we reach too large a size (1Mb).

const unsigned int kBufferGrowStep = 4096;

MallocedBuffer<char> buffer(kBufferGrowStep);

int rc = -1;

do {

rc = loadquery(L_GETINFO, buffer.data, buffer.size);

if (rc == 0) break;

buffer = MallocedBuffer<char>(buffer.size + kBufferGrowStep);

} while (buffer.size < 1024 * 1024);

if (rc == 0) {

char* buf = buffer.data;

ld_info* cur_info = nullptr;

do {

std::ostringstream str;

cur_info = reinterpret_cast<ld_info*>(buf);

char* member_name = cur_info->ldinfo_filename +

strlen(cur_info->ldinfo_filename) + 1;

if (*member_name != '\0') {

str << cur_info->ldinfo_filename << "(" << member_name << ")";

list.push_back(str.str());

str.str("");

} else {

list.push_back(cur_info->ldinfo_filename);

}

buf += cur_info->ldinfo_next;

} while (cur_info->ldinfo_next != 0);

}

#elif __sun

Link_map* p;

if (dlinfo(RTLD_SELF, RTLD_DI_LINKMAP, &p) != -1) {

for (Link_map* l = p; l != nullptr; l = l->l_next) {

list.push_back(l->l_name);

}

}

#elif _WIN32

// Windows implementation - get a handle to the process.

HANDLE process_handle = OpenProcess(PROCESS_QUERY_INFORMATION|PROCESS_VM_READ,

FALSE, GetCurrentProcessId());

if (process_handle == nullptr) {

// Cannot proceed, return an empty list.

return list;

}

// Get a list of all the modules in this process

DWORD size_1 = 0;

DWORD size_2 = 0;

// First call to get the size of module array needed

if (EnumProcessModules(process_handle, nullptr, 0, &size_1)) {

MallocedBuffer<HMODULE> modules(size_1);

// Second call to populate the module array

if (EnumProcessModules(process_handle, modules.data, size_1, &size_2)) {

for (DWORD i = 0;

i < (size_1 / sizeof(HMODULE)) && i < (size_2 / sizeof(HMODULE));

i++) {

WCHAR module_name[MAX_PATH];

// Obtain and report the full pathname for each module

if (GetModuleFileNameExW(process_handle,

modules.data[i],

module_name,

arraysize(module_name) / sizeof(WCHAR))) {

DWORD size = WideCharToMultiByte(

CP_UTF8, 0, module_name, -1, nullptr, 0, nullptr, nullptr);

char* str = new char[size];

WideCharToMultiByte(

CP_UTF8, 0, module_name, -1, str, size, nullptr, nullptr);

list.push_back(str);

}

}

}

}

// Release the handle to the process.

CloseHandle(process_handle);

#endif

return list;

}

} // namespace node

extern "C" void __DumpBacktrace(FILE* fp) {

node::DumpBacktrace(fp);

}