ai-content-maker/.venv/Lib/site-packages/torch/include/pybind11/detail/internals.h

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/*
pybind11/detail/internals.h: Internal data structure and related functions
Copyright (c) 2017 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#pragma once
#include "common.h"
#if defined(WITH_THREAD) && defined(PYBIND11_SIMPLE_GIL_MANAGEMENT)
# include "../gil.h"
#endif
#include "../pytypes.h"
#include <exception>
/// Tracks the `internals` and `type_info` ABI version independent of the main library version.
///
/// Some portions of the code use an ABI that is conditional depending on this
/// version number. That allows ABI-breaking changes to be "pre-implemented".
/// Once the default version number is incremented, the conditional logic that
/// no longer applies can be removed. Additionally, users that need not
/// maintain ABI compatibility can increase the version number in order to take
/// advantage of any functionality/efficiency improvements that depend on the
/// newer ABI.
///
/// WARNING: If you choose to manually increase the ABI version, note that
/// pybind11 may not be tested as thoroughly with a non-default ABI version, and
/// further ABI-incompatible changes may be made before the ABI is officially
/// changed to the new version.
#ifndef PYBIND11_INTERNALS_VERSION
# if PY_VERSION_HEX >= 0x030C0000 || defined(_MSC_VER)
// Version bump for Python 3.12+, before first 3.12 beta release.
// Version bump for MSVC piggy-backed on PR #4779. See comments there.
# define PYBIND11_INTERNALS_VERSION 5
# else
# define PYBIND11_INTERNALS_VERSION 4
# endif
#endif
// This requirement is mainly to reduce the support burden (see PR #4570).
static_assert(PY_VERSION_HEX < 0x030C0000 || PYBIND11_INTERNALS_VERSION >= 5,
"pybind11 ABI version 5 is the minimum for Python 3.12+");
PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
using ExceptionTranslator = void (*)(std::exception_ptr);
PYBIND11_NAMESPACE_BEGIN(detail)
constexpr const char *internals_function_record_capsule_name = "pybind11_function_record_capsule";
// Forward declarations
inline PyTypeObject *make_static_property_type();
inline PyTypeObject *make_default_metaclass();
inline PyObject *make_object_base_type(PyTypeObject *metaclass);
// The old Python Thread Local Storage (TLS) API is deprecated in Python 3.7 in favor of the new
// Thread Specific Storage (TSS) API.
#if PY_VERSION_HEX >= 0x03070000
// Avoid unnecessary allocation of `Py_tss_t`, since we cannot use
// `Py_LIMITED_API` anyway.
# if PYBIND11_INTERNALS_VERSION > 4
# define PYBIND11_TLS_KEY_REF Py_tss_t &
# if defined(__clang__)
# define PYBIND11_TLS_KEY_INIT(var) \
_Pragma("clang diagnostic push") /**/ \
_Pragma("clang diagnostic ignored \"-Wmissing-field-initializers\"") /**/ \
Py_tss_t var \
= Py_tss_NEEDS_INIT; \
_Pragma("clang diagnostic pop")
# elif defined(__GNUC__) && !defined(__INTEL_COMPILER)
# define PYBIND11_TLS_KEY_INIT(var) \
_Pragma("GCC diagnostic push") /**/ \
_Pragma("GCC diagnostic ignored \"-Wmissing-field-initializers\"") /**/ \
Py_tss_t var \
= Py_tss_NEEDS_INIT; \
_Pragma("GCC diagnostic pop")
# else
# define PYBIND11_TLS_KEY_INIT(var) Py_tss_t var = Py_tss_NEEDS_INIT;
# endif
# define PYBIND11_TLS_KEY_CREATE(var) (PyThread_tss_create(&(var)) == 0)
# define PYBIND11_TLS_GET_VALUE(key) PyThread_tss_get(&(key))
# define PYBIND11_TLS_REPLACE_VALUE(key, value) PyThread_tss_set(&(key), (value))
# define PYBIND11_TLS_DELETE_VALUE(key) PyThread_tss_set(&(key), nullptr)
# define PYBIND11_TLS_FREE(key) PyThread_tss_delete(&(key))
# else
# define PYBIND11_TLS_KEY_REF Py_tss_t *
# define PYBIND11_TLS_KEY_INIT(var) Py_tss_t *var = nullptr;
# define PYBIND11_TLS_KEY_CREATE(var) \
(((var) = PyThread_tss_alloc()) != nullptr && (PyThread_tss_create((var)) == 0))
# define PYBIND11_TLS_GET_VALUE(key) PyThread_tss_get((key))
# define PYBIND11_TLS_REPLACE_VALUE(key, value) PyThread_tss_set((key), (value))
# define PYBIND11_TLS_DELETE_VALUE(key) PyThread_tss_set((key), nullptr)
# define PYBIND11_TLS_FREE(key) PyThread_tss_free(key)
# endif
#else
// Usually an int but a long on Cygwin64 with Python 3.x
# define PYBIND11_TLS_KEY_REF decltype(PyThread_create_key())
# define PYBIND11_TLS_KEY_INIT(var) PYBIND11_TLS_KEY_REF var = 0;
# define PYBIND11_TLS_KEY_CREATE(var) (((var) = PyThread_create_key()) != -1)
# define PYBIND11_TLS_GET_VALUE(key) PyThread_get_key_value((key))
# if defined(PYPY_VERSION)
// On CPython < 3.4 and on PyPy, `PyThread_set_key_value` strangely does not set
// the value if it has already been set. Instead, it must first be deleted and
// then set again.
inline void tls_replace_value(PYBIND11_TLS_KEY_REF key, void *value) {
PyThread_delete_key_value(key);
PyThread_set_key_value(key, value);
}
# define PYBIND11_TLS_DELETE_VALUE(key) PyThread_delete_key_value(key)
# define PYBIND11_TLS_REPLACE_VALUE(key, value) \
::pybind11::detail::tls_replace_value((key), (value))
# else
# define PYBIND11_TLS_DELETE_VALUE(key) PyThread_set_key_value((key), nullptr)
# define PYBIND11_TLS_REPLACE_VALUE(key, value) PyThread_set_key_value((key), (value))
# endif
# define PYBIND11_TLS_FREE(key) (void) key
#endif
// Python loads modules by default with dlopen with the RTLD_LOCAL flag; under libc++ and possibly
// other STLs, this means `typeid(A)` from one module won't equal `typeid(A)` from another module
// even when `A` is the same, non-hidden-visibility type (e.g. from a common include). Under
// libstdc++, this doesn't happen: equality and the type_index hash are based on the type name,
// which works. If not under a known-good stl, provide our own name-based hash and equality
// functions that use the type name.
#if (PYBIND11_INTERNALS_VERSION <= 4 && defined(__GLIBCXX__)) \
|| (PYBIND11_INTERNALS_VERSION >= 5 && !defined(_LIBCPP_VERSION))
inline bool same_type(const std::type_info &lhs, const std::type_info &rhs) { return lhs == rhs; }
using type_hash = std::hash<std::type_index>;
using type_equal_to = std::equal_to<std::type_index>;
#else
inline bool same_type(const std::type_info &lhs, const std::type_info &rhs) {
return lhs.name() == rhs.name() || std::strcmp(lhs.name(), rhs.name()) == 0;
}
struct type_hash {
size_t operator()(const std::type_index &t) const {
size_t hash = 5381;
const char *ptr = t.name();
while (auto c = static_cast<unsigned char>(*ptr++)) {
hash = (hash * 33) ^ c;
}
return hash;
}
};
struct type_equal_to {
bool operator()(const std::type_index &lhs, const std::type_index &rhs) const {
return lhs.name() == rhs.name() || std::strcmp(lhs.name(), rhs.name()) == 0;
}
};
#endif
template <typename value_type>
using type_map = std::unordered_map<std::type_index, value_type, type_hash, type_equal_to>;
struct override_hash {
inline size_t operator()(const std::pair<const PyObject *, const char *> &v) const {
size_t value = std::hash<const void *>()(v.first);
value ^= std::hash<const void *>()(v.second) + 0x9e3779b9 + (value << 6) + (value >> 2);
return value;
}
};
/// Internal data structure used to track registered instances and types.
/// Whenever binary incompatible changes are made to this structure,
/// `PYBIND11_INTERNALS_VERSION` must be incremented.
struct internals {
// std::type_index -> pybind11's type information
type_map<type_info *> registered_types_cpp;
// PyTypeObject* -> base type_info(s)
std::unordered_map<PyTypeObject *, std::vector<type_info *>> registered_types_py;
std::unordered_multimap<const void *, instance *> registered_instances; // void * -> instance*
std::unordered_set<std::pair<const PyObject *, const char *>, override_hash>
inactive_override_cache;
type_map<std::vector<bool (*)(PyObject *, void *&)>> direct_conversions;
std::unordered_map<const PyObject *, std::vector<PyObject *>> patients;
std::forward_list<ExceptionTranslator> registered_exception_translators;
std::unordered_map<std::string, void *> shared_data; // Custom data to be shared across
// extensions
#if PYBIND11_INTERNALS_VERSION == 4
std::vector<PyObject *> unused_loader_patient_stack_remove_at_v5;
#endif
std::forward_list<std::string> static_strings; // Stores the std::strings backing
// detail::c_str()
PyTypeObject *static_property_type;
PyTypeObject *default_metaclass;
PyObject *instance_base;
#if defined(WITH_THREAD)
// Unused if PYBIND11_SIMPLE_GIL_MANAGEMENT is defined:
PYBIND11_TLS_KEY_INIT(tstate)
# if PYBIND11_INTERNALS_VERSION > 4
PYBIND11_TLS_KEY_INIT(loader_life_support_tls_key)
# endif // PYBIND11_INTERNALS_VERSION > 4
// Unused if PYBIND11_SIMPLE_GIL_MANAGEMENT is defined:
PyInterpreterState *istate = nullptr;
# if PYBIND11_INTERNALS_VERSION > 4
// Note that we have to use a std::string to allocate memory to ensure a unique address
// We want unique addresses since we use pointer equality to compare function records
std::string function_record_capsule_name = internals_function_record_capsule_name;
# endif
internals() = default;
internals(const internals &other) = delete;
internals &operator=(const internals &other) = delete;
~internals() {
# if PYBIND11_INTERNALS_VERSION > 4
PYBIND11_TLS_FREE(loader_life_support_tls_key);
# endif // PYBIND11_INTERNALS_VERSION > 4
// This destructor is called *after* Py_Finalize() in finalize_interpreter().
// That *SHOULD BE* fine. The following details what happens when PyThread_tss_free is
// called. PYBIND11_TLS_FREE is PyThread_tss_free on python 3.7+. On older python, it does
// nothing. PyThread_tss_free calls PyThread_tss_delete and PyMem_RawFree.
// PyThread_tss_delete just calls TlsFree (on Windows) or pthread_key_delete (on *NIX).
// Neither of those have anything to do with CPython internals. PyMem_RawFree *requires*
// that the `tstate` be allocated with the CPython allocator.
PYBIND11_TLS_FREE(tstate);
}
#endif
};
/// Additional type information which does not fit into the PyTypeObject.
/// Changes to this struct also require bumping `PYBIND11_INTERNALS_VERSION`.
struct type_info {
PyTypeObject *type;
const std::type_info *cpptype;
size_t type_size, type_align, holder_size_in_ptrs;
void *(*operator_new)(size_t);
void (*init_instance)(instance *, const void *);
void (*dealloc)(value_and_holder &v_h);
std::vector<PyObject *(*) (PyObject *, PyTypeObject *)> implicit_conversions;
std::vector<std::pair<const std::type_info *, void *(*) (void *)>> implicit_casts;
std::vector<bool (*)(PyObject *, void *&)> *direct_conversions;
buffer_info *(*get_buffer)(PyObject *, void *) = nullptr;
void *get_buffer_data = nullptr;
void *(*module_local_load)(PyObject *, const type_info *) = nullptr;
/* A simple type never occurs as a (direct or indirect) parent
* of a class that makes use of multiple inheritance.
* A type can be simple even if it has non-simple ancestors as long as it has no descendants.
*/
bool simple_type : 1;
/* True if there is no multiple inheritance in this type's inheritance tree */
bool simple_ancestors : 1;
/* for base vs derived holder_type checks */
bool default_holder : 1;
/* true if this is a type registered with py::module_local */
bool module_local : 1;
};
/// On MSVC, debug and release builds are not ABI-compatible!
#if defined(_MSC_VER) && defined(_DEBUG)
# define PYBIND11_BUILD_TYPE "_debug"
#else
# define PYBIND11_BUILD_TYPE ""
#endif
/// Let's assume that different compilers are ABI-incompatible.
/// A user can manually set this string if they know their
/// compiler is compatible.
#ifndef PYBIND11_COMPILER_TYPE
# if defined(_MSC_VER)
# define PYBIND11_COMPILER_TYPE "_msvc"
# elif defined(__INTEL_COMPILER)
# define PYBIND11_COMPILER_TYPE "_icc"
# elif defined(__clang__)
# define PYBIND11_COMPILER_TYPE "_clang"
# elif defined(__PGI)
# define PYBIND11_COMPILER_TYPE "_pgi"
# elif defined(__MINGW32__)
# define PYBIND11_COMPILER_TYPE "_mingw"
# elif defined(__CYGWIN__)
# define PYBIND11_COMPILER_TYPE "_gcc_cygwin"
# elif defined(__GNUC__)
# define PYBIND11_COMPILER_TYPE "_gcc"
# else
# define PYBIND11_COMPILER_TYPE "_unknown"
# endif
#endif
/// Also standard libs
#ifndef PYBIND11_STDLIB
# if defined(_LIBCPP_VERSION)
# define PYBIND11_STDLIB "_libcpp"
# elif defined(__GLIBCXX__) || defined(__GLIBCPP__)
# define PYBIND11_STDLIB "_libstdcpp"
# else
# define PYBIND11_STDLIB ""
# endif
#endif
/// On Linux/OSX, changes in __GXX_ABI_VERSION__ indicate ABI incompatibility.
/// On MSVC, changes in _MSC_VER may indicate ABI incompatibility (#2898).
#ifndef PYBIND11_BUILD_ABI
# if defined(__GXX_ABI_VERSION)
# define PYBIND11_BUILD_ABI "_cxxabi" PYBIND11_TOSTRING(__GXX_ABI_VERSION)
# elif defined(_MSC_VER)
# define PYBIND11_BUILD_ABI "_mscver" PYBIND11_TOSTRING(_MSC_VER)
# else
# define PYBIND11_BUILD_ABI ""
# endif
#endif
#ifndef PYBIND11_INTERNALS_KIND
# if defined(WITH_THREAD)
# define PYBIND11_INTERNALS_KIND ""
# else
# define PYBIND11_INTERNALS_KIND "_without_thread"
# endif
#endif
#define PYBIND11_INTERNALS_ID \
"__pybind11_internals_v" PYBIND11_TOSTRING(PYBIND11_INTERNALS_VERSION) \
PYBIND11_INTERNALS_KIND PYBIND11_COMPILER_TYPE PYBIND11_STDLIB PYBIND11_BUILD_ABI \
PYBIND11_BUILD_TYPE "__"
#define PYBIND11_MODULE_LOCAL_ID \
"__pybind11_module_local_v" PYBIND11_TOSTRING(PYBIND11_INTERNALS_VERSION) \
PYBIND11_INTERNALS_KIND PYBIND11_COMPILER_TYPE PYBIND11_STDLIB PYBIND11_BUILD_ABI \
PYBIND11_BUILD_TYPE "__"
/// Each module locally stores a pointer to the `internals` data. The data
/// itself is shared among modules with the same `PYBIND11_INTERNALS_ID`.
inline internals **&get_internals_pp() {
static internals **internals_pp = nullptr;
return internals_pp;
}
// forward decl
inline void translate_exception(std::exception_ptr);
template <class T,
enable_if_t<std::is_same<std::nested_exception, remove_cvref_t<T>>::value, int> = 0>
bool handle_nested_exception(const T &exc, const std::exception_ptr &p) {
std::exception_ptr nested = exc.nested_ptr();
if (nested != nullptr && nested != p) {
translate_exception(nested);
return true;
}
return false;
}
template <class T,
enable_if_t<!std::is_same<std::nested_exception, remove_cvref_t<T>>::value, int> = 0>
bool handle_nested_exception(const T &exc, const std::exception_ptr &p) {
if (const auto *nep = dynamic_cast<const std::nested_exception *>(std::addressof(exc))) {
return handle_nested_exception(*nep, p);
}
return false;
}
inline bool raise_err(PyObject *exc_type, const char *msg) {
if (PyErr_Occurred()) {
raise_from(exc_type, msg);
return true;
}
set_error(exc_type, msg);
return false;
}
inline void translate_exception(std::exception_ptr p) {
if (!p) {
return;
}
try {
std::rethrow_exception(p);
} catch (error_already_set &e) {
handle_nested_exception(e, p);
e.restore();
return;
} catch (const builtin_exception &e) {
// Could not use template since it's an abstract class.
if (const auto *nep = dynamic_cast<const std::nested_exception *>(std::addressof(e))) {
handle_nested_exception(*nep, p);
}
e.set_error();
return;
} catch (const std::bad_alloc &e) {
handle_nested_exception(e, p);
raise_err(PyExc_MemoryError, e.what());
return;
} catch (const std::domain_error &e) {
handle_nested_exception(e, p);
raise_err(PyExc_ValueError, e.what());
return;
} catch (const std::invalid_argument &e) {
handle_nested_exception(e, p);
raise_err(PyExc_ValueError, e.what());
return;
} catch (const std::length_error &e) {
handle_nested_exception(e, p);
raise_err(PyExc_ValueError, e.what());
return;
} catch (const std::out_of_range &e) {
handle_nested_exception(e, p);
raise_err(PyExc_IndexError, e.what());
return;
} catch (const std::range_error &e) {
handle_nested_exception(e, p);
raise_err(PyExc_ValueError, e.what());
return;
} catch (const std::overflow_error &e) {
handle_nested_exception(e, p);
raise_err(PyExc_OverflowError, e.what());
return;
} catch (const std::exception &e) {
handle_nested_exception(e, p);
raise_err(PyExc_RuntimeError, e.what());
return;
} catch (const std::nested_exception &e) {
handle_nested_exception(e, p);
raise_err(PyExc_RuntimeError, "Caught an unknown nested exception!");
return;
} catch (...) {
raise_err(PyExc_RuntimeError, "Caught an unknown exception!");
return;
}
}
#if !defined(__GLIBCXX__)
inline void translate_local_exception(std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (error_already_set &e) {
e.restore();
return;
} catch (const builtin_exception &e) {
e.set_error();
return;
}
}
#endif
inline object get_python_state_dict() {
object state_dict;
#if PYBIND11_INTERNALS_VERSION <= 4 || PY_VERSION_HEX < 0x03080000 || defined(PYPY_VERSION)
state_dict = reinterpret_borrow<object>(PyEval_GetBuiltins());
#else
# if PY_VERSION_HEX < 0x03090000
PyInterpreterState *istate = _PyInterpreterState_Get();
# else
PyInterpreterState *istate = PyInterpreterState_Get();
# endif
if (istate) {
state_dict = reinterpret_borrow<object>(PyInterpreterState_GetDict(istate));
}
#endif
if (!state_dict) {
raise_from(PyExc_SystemError, "pybind11::detail::get_python_state_dict() FAILED");
throw error_already_set();
}
return state_dict;
}
inline object get_internals_obj_from_state_dict(handle state_dict) {
return reinterpret_borrow<object>(dict_getitemstring(state_dict.ptr(), PYBIND11_INTERNALS_ID));
}
inline internals **get_internals_pp_from_capsule(handle obj) {
void *raw_ptr = PyCapsule_GetPointer(obj.ptr(), /*name=*/nullptr);
if (raw_ptr == nullptr) {
raise_from(PyExc_SystemError, "pybind11::detail::get_internals_pp_from_capsule() FAILED");
throw error_already_set();
}
return static_cast<internals **>(raw_ptr);
}
/// Return a reference to the current `internals` data
PYBIND11_NOINLINE internals &get_internals() {
auto **&internals_pp = get_internals_pp();
if (internals_pp && *internals_pp) {
return **internals_pp;
}
#if defined(WITH_THREAD)
# if defined(PYBIND11_SIMPLE_GIL_MANAGEMENT)
gil_scoped_acquire gil;
# else
// Ensure that the GIL is held since we will need to make Python calls.
// Cannot use py::gil_scoped_acquire here since that constructor calls get_internals.
struct gil_scoped_acquire_local {
gil_scoped_acquire_local() : state(PyGILState_Ensure()) {}
gil_scoped_acquire_local(const gil_scoped_acquire_local &) = delete;
gil_scoped_acquire_local &operator=(const gil_scoped_acquire_local &) = delete;
~gil_scoped_acquire_local() { PyGILState_Release(state); }
const PyGILState_STATE state;
} gil;
# endif
#endif
error_scope err_scope;
dict state_dict = get_python_state_dict();
if (object internals_obj = get_internals_obj_from_state_dict(state_dict)) {
internals_pp = get_internals_pp_from_capsule(internals_obj);
}
if (internals_pp && *internals_pp) {
// We loaded the internals through `state_dict`, which means that our `error_already_set`
// and `builtin_exception` may be different local classes than the ones set up in the
// initial exception translator, below, so add another for our local exception classes.
//
// libstdc++ doesn't require this (types there are identified only by name)
// libc++ with CPython doesn't require this (types are explicitly exported)
// libc++ with PyPy still need it, awaiting further investigation
#if !defined(__GLIBCXX__)
(*internals_pp)->registered_exception_translators.push_front(&translate_local_exception);
#endif
} else {
if (!internals_pp) {
internals_pp = new internals *();
}
auto *&internals_ptr = *internals_pp;
internals_ptr = new internals();
#if defined(WITH_THREAD)
PyThreadState *tstate = PyThreadState_Get();
// NOLINTNEXTLINE(bugprone-assignment-in-if-condition)
if (!PYBIND11_TLS_KEY_CREATE(internals_ptr->tstate)) {
pybind11_fail("get_internals: could not successfully initialize the tstate TSS key!");
}
PYBIND11_TLS_REPLACE_VALUE(internals_ptr->tstate, tstate);
# if PYBIND11_INTERNALS_VERSION > 4
// NOLINTNEXTLINE(bugprone-assignment-in-if-condition)
if (!PYBIND11_TLS_KEY_CREATE(internals_ptr->loader_life_support_tls_key)) {
pybind11_fail("get_internals: could not successfully initialize the "
"loader_life_support TSS key!");
}
# endif
internals_ptr->istate = tstate->interp;
#endif
state_dict[PYBIND11_INTERNALS_ID] = capsule(internals_pp);
internals_ptr->registered_exception_translators.push_front(&translate_exception);
internals_ptr->static_property_type = make_static_property_type();
internals_ptr->default_metaclass = make_default_metaclass();
internals_ptr->instance_base = make_object_base_type(internals_ptr->default_metaclass);
}
return **internals_pp;
}
// the internals struct (above) is shared between all the modules. local_internals are only
// for a single module. Any changes made to internals may require an update to
// PYBIND11_INTERNALS_VERSION, breaking backwards compatibility. local_internals is, by design,
// restricted to a single module. Whether a module has local internals or not should not
// impact any other modules, because the only things accessing the local internals is the
// module that contains them.
struct local_internals {
type_map<type_info *> registered_types_cpp;
std::forward_list<ExceptionTranslator> registered_exception_translators;
#if defined(WITH_THREAD) && PYBIND11_INTERNALS_VERSION == 4
// For ABI compatibility, we can't store the loader_life_support TLS key in
// the `internals` struct directly. Instead, we store it in `shared_data` and
// cache a copy in `local_internals`. If we allocated a separate TLS key for
// each instance of `local_internals`, we could end up allocating hundreds of
// TLS keys if hundreds of different pybind11 modules are loaded (which is a
// plausible number).
PYBIND11_TLS_KEY_INIT(loader_life_support_tls_key)
// Holds the shared TLS key for the loader_life_support stack.
struct shared_loader_life_support_data {
PYBIND11_TLS_KEY_INIT(loader_life_support_tls_key)
shared_loader_life_support_data() {
// NOLINTNEXTLINE(bugprone-assignment-in-if-condition)
if (!PYBIND11_TLS_KEY_CREATE(loader_life_support_tls_key)) {
pybind11_fail("local_internals: could not successfully initialize the "
"loader_life_support TLS key!");
}
}
// We can't help but leak the TLS key, because Python never unloads extension modules.
};
local_internals() {
auto &internals = get_internals();
// Get or create the `loader_life_support_stack_key`.
auto &ptr = internals.shared_data["_life_support"];
if (!ptr) {
ptr = new shared_loader_life_support_data;
}
loader_life_support_tls_key
= static_cast<shared_loader_life_support_data *>(ptr)->loader_life_support_tls_key;
}
#endif // defined(WITH_THREAD) && PYBIND11_INTERNALS_VERSION == 4
};
/// Works like `get_internals`, but for things which are locally registered.
inline local_internals &get_local_internals() {
// Current static can be created in the interpreter finalization routine. If the later will be
// destroyed in another static variable destructor, creation of this static there will cause
// static deinitialization fiasco. In order to avoid it we avoid destruction of the
// local_internals static. One can read more about the problem and current solution here:
// https://google.github.io/styleguide/cppguide.html#Static_and_Global_Variables
static auto *locals = new local_internals();
return *locals;
}
/// Constructs a std::string with the given arguments, stores it in `internals`, and returns its
/// `c_str()`. Such strings objects have a long storage duration -- the internal strings are only
/// cleared when the program exits or after interpreter shutdown (when embedding), and so are
/// suitable for c-style strings needed by Python internals (such as PyTypeObject's tp_name).
template <typename... Args>
const char *c_str(Args &&...args) {
auto &strings = get_internals().static_strings;
strings.emplace_front(std::forward<Args>(args)...);
return strings.front().c_str();
}
inline const char *get_function_record_capsule_name() {
#if PYBIND11_INTERNALS_VERSION > 4
return get_internals().function_record_capsule_name.c_str();
#else
return nullptr;
#endif
}
// Determine whether or not the following capsule contains a pybind11 function record.
// Note that we use `internals` to make sure that only ABI compatible records are touched.
//
// This check is currently used in two places:
// - An important optimization in functional.h to avoid overhead in C++ -> Python -> C++
// - The sibling feature of cpp_function to allow overloads
inline bool is_function_record_capsule(const capsule &cap) {
// Pointer equality as we rely on internals() to ensure unique pointers
return cap.name() == get_function_record_capsule_name();
}
PYBIND11_NAMESPACE_END(detail)
/// Returns a named pointer that is shared among all extension modules (using the same
/// pybind11 version) running in the current interpreter. Names starting with underscores
/// are reserved for internal usage. Returns `nullptr` if no matching entry was found.
PYBIND11_NOINLINE void *get_shared_data(const std::string &name) {
auto &internals = detail::get_internals();
auto it = internals.shared_data.find(name);
return it != internals.shared_data.end() ? it->second : nullptr;
}
/// Set the shared data that can be later recovered by `get_shared_data()`.
PYBIND11_NOINLINE void *set_shared_data(const std::string &name, void *data) {
detail::get_internals().shared_data[name] = data;
return data;
}
/// Returns a typed reference to a shared data entry (by using `get_shared_data()`) if
/// such entry exists. Otherwise, a new object of default-constructible type `T` is
/// added to the shared data under the given name and a reference to it is returned.
template <typename T>
T &get_or_create_shared_data(const std::string &name) {
auto &internals = detail::get_internals();
auto it = internals.shared_data.find(name);
T *ptr = (T *) (it != internals.shared_data.end() ? it->second : nullptr);
if (!ptr) {
ptr = new T();
internals.shared_data[name] = ptr;
}
return *ptr;
}
PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)