gcc/libstdc++-v3/include/std/stacktrace

// <stacktrace> -*- C++ -*-

// Copyright The GNU Toolchain Authors.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

#ifndef _GLIBCXX_STACKTRACE
#define _GLIBCXX_STACKTRACE 1

#pragma GCC system_header

#include <bits/c++config.h>

#if __cplusplus > 202002L && _GLIBCXX_HAVE_STACKTRACE
#include <compare>
#include <string>
#include <sstream>
#include <bits/stl_algobase.h>
#include <bits/stl_algo.h>
#include <bits/stl_iterator.h>
#include <bits/stl_uninitialized.h>
#include <cxxabi.h>

struct __glibcxx_backtrace_state;
struct __glibcxx_backtrace_simple_data;

extern "C"
{
__glibcxx_backtrace_state*
__glibcxx_backtrace_create_state(const char*, int,
				 void(*)(void*, const char*, int),
				 void*);

int
__glibcxx_backtrace_simple(__glibcxx_backtrace_state*, int,
			   int (*) (void*, uintptr_t),
			   void(*)(void*, const char*, int),
			   void*);
int
__glibcxx_backtrace_pcinfo(__glibcxx_backtrace_state*, uintptr_t,
			   int (*)(void*, uintptr_t,
				   const char*, int, const char*),
			   void(*)(void*, const char*, int),
			   void*);

int
__glibcxx_backtrace_syminfo(__glibcxx_backtrace_state*, uintptr_t addr,
			    void (*) (void*, uintptr_t, const char*,
				      uintptr_t, uintptr_t),
			    void(*)(void*, const char*, int),
			    void*);
}

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

#define __cpp_lib_stacktrace 202011L

  // [stacktrace.entry], class stacktrace_entry
  class stacktrace_entry
  {
    using uint_least32_t = __UINT_LEAST32_TYPE__;
    using uintptr_t = __UINTPTR_TYPE__;

  public:
    using native_handle_type = uintptr_t;

    // [stacktrace.entry.ctor], constructors

    constexpr
    stacktrace_entry() noexcept = default;

    constexpr
    stacktrace_entry(const stacktrace_entry& __other) noexcept = default;

    constexpr stacktrace_entry&
    operator=(const stacktrace_entry& __other) noexcept = default;

    ~stacktrace_entry() = default;

    // [stacktrace.entry.obs], observers

    constexpr native_handle_type
    native_handle() const noexcept { return _M_pc; }

    constexpr explicit operator bool() const noexcept { return _M_pc != -1; }

    // [stacktrace.entry.query], query
    string
    description() const
    {
      string __s;
      _M_get_info(&__s, nullptr, nullptr);
      return __s;
    }

    string
    source_file() const
    {
      string __s;
      _M_get_info(nullptr, &__s, nullptr);
      return __s;
    }

    uint_least32_t
    source_line() const
    {
      int __line = 0;
      _M_get_info(nullptr, nullptr, &__line);
      return __line;
    }

    // [stacktrace.entry.cmp], comparison
    friend constexpr bool
    operator==(const stacktrace_entry& __x,
	       const stacktrace_entry& __y) noexcept
    { return __x._M_pc == __y._M_pc; }

    friend constexpr strong_ordering
    operator<=>(const stacktrace_entry& __x,
		const stacktrace_entry& __y) noexcept
    { return __x._M_pc <=> __y._M_pc; }

  private:
    native_handle_type _M_pc = -1;

    template<typename _Allocator> friend class basic_stacktrace;

    static __glibcxx_backtrace_state*
    _S_init()
    {
      static __glibcxx_backtrace_state* __state
	= __glibcxx_backtrace_create_state(nullptr, 1, nullptr, nullptr);
      return __state;
    }

    template<typename _CharT, typename _Traits>
      friend basic_ostream<_CharT, _Traits>&
      operator<<(basic_ostream<_CharT, _Traits>&, const stacktrace_entry&);

    bool
    _M_get_info(string* __desc, string* __file, int* __line) const
    {
      if (!*this)
	return false;

      struct _Data
      {
	string* _M_desc;
	string* _M_file;
	int* _M_line;
      } __data = { __desc, __file, __line };

      auto __cb = [](void* __data, uintptr_t, const char* __filename,
		     int __lineno, const char* __function) -> int {
	  auto& __d = *static_cast<_Data*>(__data);
	  if (__function && __d._M_desc)
	    *__d._M_desc = _S_demangle(__function);
	  if (__filename && __d._M_file)
	    *__d._M_file = __filename;
	  if (__d._M_line)
	    *__d._M_line = __lineno;
	  return __function != nullptr;
      };
      const auto __state = _S_init();
      if (::__glibcxx_backtrace_pcinfo(__state, _M_pc, +__cb, nullptr, &__data))
	return true;
      if (__desc && __desc->empty())
	{
	  auto __cb2 = [](void* __data, uintptr_t, const char* __symname,
	      uintptr_t, uintptr_t) {
	      if (__symname)
		*static_cast<_Data*>(__data)->_M_desc = _S_demangle(__symname);
	  };
	  if (::__glibcxx_backtrace_syminfo(__state, _M_pc, +__cb2, nullptr,
					    &__data))
	    return true;
	}
      return false;
    }

    static string
    _S_demangle(const char* __name)
    {
      string __s;
      int __status;
      char* __str = __cxxabiv1::__cxa_demangle(__name, nullptr, nullptr,
					       &__status);
      if (__status == 0)
	__s = __str;
      __builtin_free(__str);
      return __s;
    }
  };

  // [stacktrace.basic], class template basic_stacktrace
  template<typename _Allocator>
    class basic_stacktrace
    {
      using _AllocTraits = allocator_traits<_Allocator>;

    public:
      using value_type = stacktrace_entry;
      using const_reference = const value_type&;
      using reference = value_type&;
      using const_iterator
	= __gnu_cxx::__normal_iterator<value_type*, basic_stacktrace>;
      using iterator = const_iterator;
      using reverse_iterator = std::reverse_iterator<iterator>;
      using const_reverse_iterator = std::reverse_iterator<const_iterator>;
      using difference_type = ptrdiff_t;
      using size_type = unsigned short;
      using allocator_type = _Allocator;

      // [stacktrace.basic.ctor], creation and assignment

      static basic_stacktrace
      current(const allocator_type& __alloc = allocator_type()) noexcept
      {
	return current(0, size_type(-1), __alloc);
      }

      static basic_stacktrace
      current(size_type __skip,
	      const allocator_type& __alloc = allocator_type()) noexcept
      {
	return current(__skip, size_type(-1), __alloc);
      }

      static basic_stacktrace
      current(size_type __skip, size_type __max_depth,
	      const allocator_type& __alloc = allocator_type()) noexcept
      {
	__glibcxx_assert(__skip <= (size_type(-1) - __max_depth));

	auto __state = stacktrace_entry::_S_init();
	basic_stacktrace __ret(__alloc);
	if (!__ret._M_reserve(std::min<int>(__max_depth, 64)))
	  return __ret;

	auto __cb = [](void* __data, uintptr_t __pc) {
	  auto& __s = *static_cast<basic_stacktrace*>(__data);
	  stacktrace_entry __f;
	  __f._M_pc = __pc;
	  if (__s._M_push_back(__f))
	    return 0;
	  return 1;
	};

	if (__glibcxx_backtrace_simple(__state, __skip, +__cb, nullptr,
				       std::__addressof(__ret)))
	  {
	    __ret._M_clear();
	  }
	return __ret;
      }

      basic_stacktrace()
      noexcept(is_nothrow_default_constructible_v<allocator_type>)
      { }

      explicit
      basic_stacktrace(const allocator_type& __alloc) noexcept
      : _M_alloc(__alloc)
      { }

      basic_stacktrace(const basic_stacktrace& __other) noexcept
      : basic_stacktrace(__other, __other._M_alloc)
      { }

      basic_stacktrace(basic_stacktrace&& __other) noexcept
      : _M_alloc(std::move(__other._M_alloc)),
	_M_impl(std::__exchange(__other._M_impl, {}))
      { }

      basic_stacktrace(const basic_stacktrace& __other,
		       const allocator_type& __alloc) noexcept
      : _M_alloc(__alloc)
      {
	if (const auto __s = __other._M_impl._M_size)
	  if (auto __f = _M_impl._M_allocate(_M_alloc, __s))
	    {
	      std::uninitialized_copy_n(__other.begin(), __s, __f);
	      _M_impl._M_size = __s;
	    }
      }

      basic_stacktrace(basic_stacktrace&& __other,
		       const allocator_type& __alloc) noexcept
      : _M_alloc(__alloc)
      {
	if constexpr (_Allocator::is_always_equal::value)
	  {
	    _M_impl = std::__exchange(__other._M_impl, {});
	  }
	else if (_M_alloc == __other._M_alloc)
	  {
	    _M_impl = std::__exchange(__other._M_impl, {});
	  }
      }

      basic_stacktrace&
      operator=(const basic_stacktrace& __other) noexcept
      {
	if (std::__addressof(__other) == this)
	  return *this;

	constexpr bool __pocca
	  = _AllocTraits::propagate_on_container_copy_assignment::value;
	constexpr bool __always_eq = _AllocTraits::is_always_equal::value;

	const auto __s = __other.size();

	if constexpr (!__always_eq && __pocca)
	  {
	    if (_M_alloc != __other._M_alloc)
	      {
		// Cannot keep the same storage, so deallocate it now.
		_M_clear();
	      }
	  }

	if (_M_impl._M_capacity < __s)
	  {
	    // Need to allocate new storage.
	    _M_clear();

	    // Use the allocator we will have after this function returns.
	    auto& __alloc = __pocca ? __other._M_alloc : _M_alloc;
	    if (auto __f = _M_impl._M_allocate(__alloc, __s))
	      {
		std::uninitialized_copy_n(__other.begin(), __s, __f);
		_M_impl._M_size = __s;
	      }
	  }
	else
	  {
	    // Current storage is large enough and can be freed by whichever
	    // allocator we will have after this function returns.
	    auto __to = std::copy_n(__other.begin(), __s, begin());
	    std::destroy(__to, end());
	    _M_impl._M_size = __s;
	  }

	if constexpr (__pocca)
	  _M_alloc = __other._M_alloc;

	return *this;
      }

      basic_stacktrace&
      operator=(basic_stacktrace&& __other) noexcept
      {
	if (std::__addressof(__other) == this)
	  return *this;

	constexpr bool __pocma
	  = _AllocTraits::propagate_on_container_move_assignment::value;

	if constexpr (_AllocTraits::is_always_equal::value)
	  std::swap(_M_impl, __other._M_impl);
	else if (_M_alloc == __other._M_alloc)
	  std::swap(_M_impl, __other._M_impl);
	else
	  {
	    const auto __s = __other.size();

	    if constexpr (__pocma || _M_impl._M_capacity < __s)
	      {
		// Need to allocate new storage.
		_M_clear();

		// Use the allocator we will have after this function returns.
		auto& __alloc = __pocma ? __other._M_alloc : _M_alloc;
		if (auto __f = _M_impl._M_allocate(__alloc, __s))
		  std::uninitialized_copy_n(__other.begin(), __s, __f);
	      }
	    else
	      {
		// Current storage is large enough.
		auto __first = __other.begin();
		auto __mid = __first + std::min(__s, _M_impl._M_size);
		auto __last = __other.end();
		auto __to = std::copy(__first, __mid, begin());
		__to = std::uninitialized_copy(__mid, __last, __to);
		std::destroy(__to, end());
	      }
	    _M_impl._M_size = __s;
	  }

	if constexpr (__pocma)
	  _M_alloc = std::move(__other._M_alloc);

	return *this;
      }

      constexpr ~basic_stacktrace()
      {
	_M_clear();
      }

      // [stacktrace.basic.obs], observers
      allocator_type get_allocator() const noexcept { return _M_alloc; }

      const_iterator
      begin() const noexcept
      { return const_iterator{_M_impl._M_frames}; }

      const_iterator
      end() const noexcept
      { return begin() + size(); }

      const_reverse_iterator
      rbegin() const noexcept
      { return std::make_reverse_iterator(end()); }

      const_reverse_iterator
      rend() const noexcept
      { return std::make_reverse_iterator(begin()); }

      const_iterator cbegin() const noexcept { return begin(); }
      const_iterator cend() const noexcept { return end(); }
      const_reverse_iterator crbegin() const noexcept { return rbegin(); };
      const_reverse_iterator crend() const noexcept { return rend(); };

      [[nodiscard]] bool empty() const noexcept { return size() == 0; }
      size_type size() const noexcept { return _M_impl._M_size; }
      size_type max_size() const noexcept { return size_type(-1); }

      const_reference
      operator[](size_type __n) const noexcept
      {
	__glibcxx_assert(__n < size());
	return begin()[__n];
      }

      const_reference
      at(size_type __n) const
      {
	if (__n >= size())
	  __throw_out_of_range("basic_stack_trace::at: bad frame number");
	return begin()[__n];
      }

      // [stacktrace.basic.cmp], comparisons
      template<typename _Allocator2>
	friend bool
	operator==(const basic_stacktrace& __x,
		   const basic_stacktrace<_Allocator2>& __y) noexcept
	{ return std::equal(__x.begin(), __x.end(), __y.begin(), __y.end()); }

      template<typename _Allocator2>
	friend strong_ordering
	operator<=>(const basic_stacktrace& __x,
		    const basic_stacktrace<_Allocator2>& __y) noexcept
	{
	  if (auto __s = __x.size() <=> __y.size(); __s != 0)
	    return __s;
	  return std::lexicographical_compare_three_way(__x.begin(), __x.end(),
							__y.begin(), __y.end());
	}

      // [stacktrace.basic.mod], modifiers
      void
      swap(basic_stacktrace& __other) noexcept
      {
	std::swap(_M_impl. __other._M_impl);
	if constexpr (_AllocTraits::propagate_on_container_swap::value)
	  std::swap(_M_alloc, __other._M_alloc);
      }

    private:
      bool
      _M_reserve(size_type __n) noexcept
      {
	return _M_impl._M_allocate(_M_alloc, __n) != nullptr;
      }

      bool
      _M_push_back(const value_type& __x) noexcept
      {
	return _M_impl._M_push_back(_M_alloc, __x);
      }

      void
      _M_clear() noexcept
      {
	_M_impl._M_destroy();
	_M_impl._M_deallocate(_M_alloc);
      }

      struct _Impl
      {
	using pointer = typename _AllocTraits::pointer;

	pointer	  _M_frames   = nullptr;
	size_type _M_size     = 0;
	size_type _M_capacity = 0;

	// Precondition: _M_frames == nullptr
	pointer
	_M_allocate(allocator_type& __alloc, size_type __n) noexcept
	{
	  __try
	    {
	      _M_frames = __n ? __alloc.allocate(__n) : nullptr;
	      _M_capacity = __n;
	    }
	  __catch (...)
	    {
	      _M_frames = nullptr;
	      _M_capacity = 0;
	    }
	  return _M_frames;
	}

	void
	_M_deallocate(allocator_type& __alloc) noexcept
	{
	  if (_M_capacity)
	    {
	      __alloc.deallocate(_M_frames, _M_capacity);
	      _M_frames = nullptr;
	      _M_capacity = 0;
	    }
	}

	void
	_M_destroy() noexcept
	{
	  std::destroy_n(_M_frames, _M_size);
	  _M_size = 0;
	}

	bool
	_M_push_back(allocator_type& __alloc,
		     const stacktrace_entry& __f) noexcept
	{
	  if (_M_size == _M_capacity)
	    {
	      _Impl __tmp;
	      if (auto __f = __tmp._M_allocate(__alloc, _M_capacity * 2))
		std::uninitialized_copy_n(_M_frames, _M_size, __f);
	      else
		return false;
	      _M_deallocate(__alloc);
	      std::swap(*this, __tmp);
	    }
	  stacktrace_entry* __addr = std::to_address(_M_frames + _M_size++);
	  std::construct_at(__addr, __f);
	  return true;
	}

      };

      [[no_unique_address]] allocator_type  _M_alloc{};

      _Impl _M_impl{};
    };

  // basic_stacktrace typedef names
  using stacktrace = basic_stacktrace<allocator<stacktrace_entry>>;

  // [stacktrace.basic.nonmem], non-member functions
  template<typename _Allocator>
    inline void
    swap(basic_stacktrace<_Allocator>& __a, basic_stacktrace<_Allocator>& __b)
    noexcept(noexcept(__a.swap(__b)))
    { __a.swap(__b); }

  template<typename _CharT, typename _Traits>
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>& __os,
	       const stacktrace_entry& __f)
    {
      string __desc, __file;
      int __line;
      if (__f._M_get_info(&__desc, &__file, &__line))
	{
	  __os.width(4);
	  __os << __desc << " at " << __file << ':' << __line;
	}
      return __os;
    }

  template<typename _CharT, typename _Traits, typename _Allocator>
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>& __os,
	       const basic_stacktrace<_Allocator>& __st)
    {
      for (stacktrace::size_type __i = 0; __i < __st.size(); ++__i)
	{
	  __os.width(4);
	  __os << __i << "# " << __st[__i] << '\n';
	}
      return __os;
    }

  inline string
  to_string(const stacktrace_entry& __f)
  {
    std::ostringstream __os;
    __os << __f;
    return std::move(__os).str();
  }

  template<typename _Allocator>
    string
    to_string(const basic_stacktrace<_Allocator>& __st)
    {
      std::ostringstream __os;
      __os << __st;
      return std::move(__os).str();
    }

  namespace pmr
  {
    template<typename _Tp> class polymorphic_allocator;
    using stacktrace
      = basic_stacktrace<polymorphic_allocator<stacktrace_entry>>;
  }

  // [stacktrace.basic.hash], hash support

  template<>
    struct hash<stacktrace_entry>
    {
      size_t
      operator()(const stacktrace_entry& __f) const noexcept
      {
	using __h = hash<stacktrace_entry::native_handle_type>;
	return __h()(__f.native_handle());
      }
    };

  template<typename _Allocator>
    struct hash<basic_stacktrace<_Allocator>>
    {
      size_t
      operator()(const basic_stacktrace<_Allocator>& __st) const noexcept
      {
	hash<stacktrace_entry::native_handle_type> __h;
	size_t __val = _Hash_impl::hash(__st.size());
	for (const auto& __f : __st)
	  __val = _Hash_impl::__hash_combine(__h(__f), __val);
	return __val;
      }
    };

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++23

#endif /* _GLIBCXX_STACKTRACE */