blob: a0e639583e03f676e0f14c25869884bdb8c1144f [file] [log] [blame]
/*
pybind11/pybind11.h: Main header file of the C++11 python
binding generator library
Copyright (c) 2016 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
#if defined(__INTEL_COMPILER)
# pragma warning push
# pragma warning disable 68 // integer conversion resulted in a change of sign
# pragma warning disable 186 // pointless comparison of unsigned integer with zero
# pragma warning disable 878 // incompatible exception specifications
# pragma warning disable 1334 // the "template" keyword used for syntactic disambiguation may only be used within a template
# pragma warning disable 1682 // implicit conversion of a 64-bit integral type to a smaller integral type (potential portability problem)
# pragma warning disable 1786 // function "strdup" was declared deprecated
# pragma warning disable 1875 // offsetof applied to non-POD (Plain Old Data) types is nonstandard
# pragma warning disable 2196 // warning #2196: routine is both "inline" and "noinline"
#elif defined(_MSC_VER)
# pragma warning(push)
# pragma warning(disable: 4100) // warning C4100: Unreferenced formal parameter
# pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
# pragma warning(disable: 4512) // warning C4512: Assignment operator was implicitly defined as deleted
# pragma warning(disable: 4800) // warning C4800: 'int': forcing value to bool 'true' or 'false' (performance warning)
# pragma warning(disable: 4996) // warning C4996: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name
# pragma warning(disable: 4702) // warning C4702: unreachable code
# pragma warning(disable: 4522) // warning C4522: multiple assignment operators specified
#elif defined(__GNUG__) && !defined(__clang__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wunused-but-set-parameter"
# pragma GCC diagnostic ignored "-Wunused-but-set-variable"
# pragma GCC diagnostic ignored "-Wmissing-field-initializers"
# pragma GCC diagnostic ignored "-Wstrict-aliasing"
# pragma GCC diagnostic ignored "-Wattributes"
# if __GNUC__ >= 7
# pragma GCC diagnostic ignored "-Wnoexcept-type"
# endif
#endif
#include "attr.h"
#include "options.h"
#include "detail/class.h"
#include "detail/init.h"
#if defined(__GNUG__) && !defined(__clang__)
# include <cxxabi.h>
#endif
NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
/// Wraps an arbitrary C++ function/method/lambda function/.. into a callable Python object
class cpp_function : public function {
public:
cpp_function() { }
cpp_function(std::nullptr_t) { }
/// Construct a cpp_function from a vanilla function pointer
template <typename Return, typename... Args, typename... Extra>
cpp_function(Return (*f)(Args...), const Extra&... extra) {
initialize(f, f, extra...);
}
/// Construct a cpp_function from a lambda function (possibly with internal state)
template <typename Func, typename... Extra,
typename = detail::enable_if_t<detail::is_lambda<Func>::value>>
cpp_function(Func &&f, const Extra&... extra) {
initialize(std::forward<Func>(f),
(detail::function_signature_t<Func> *) nullptr, extra...);
}
/// Construct a cpp_function from a class method (non-const)
template <typename Return, typename Class, typename... Arg, typename... Extra>
cpp_function(Return (Class::*f)(Arg...), const Extra&... extra) {
initialize([f](Class *c, Arg... args) -> Return { return (c->*f)(args...); },
(Return (*) (Class *, Arg...)) nullptr, extra...);
}
/// Construct a cpp_function from a class method (const)
template <typename Return, typename Class, typename... Arg, typename... Extra>
cpp_function(Return (Class::*f)(Arg...) const, const Extra&... extra) {
initialize([f](const Class *c, Arg... args) -> Return { return (c->*f)(args...); },
(Return (*)(const Class *, Arg ...)) nullptr, extra...);
}
/// Return the function name
object name() const { return attr("__name__"); }
protected:
/// Space optimization: don't inline this frequently instantiated fragment
PYBIND11_NOINLINE detail::function_record *make_function_record() {
return new detail::function_record();
}
/// Special internal constructor for functors, lambda functions, etc.
template <typename Func, typename Return, typename... Args, typename... Extra>
void initialize(Func &&f, Return (*)(Args...), const Extra&... extra) {
using namespace detail;
struct capture { remove_reference_t<Func> f; };
/* Store the function including any extra state it might have (e.g. a lambda capture object) */
auto rec = make_function_record();
/* Store the capture object directly in the function record if there is enough space */
if (sizeof(capture) <= sizeof(rec->data)) {
/* Without these pragmas, GCC warns that there might not be
enough space to use the placement new operator. However, the
'if' statement above ensures that this is the case. */
#if defined(__GNUG__) && !defined(__clang__) && __GNUC__ >= 6
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wplacement-new"
#endif
new ((capture *) &rec->data) capture { std::forward<Func>(f) };
#if defined(__GNUG__) && !defined(__clang__) && __GNUC__ >= 6
# pragma GCC diagnostic pop
#endif
if (!std::is_trivially_destructible<Func>::value)
rec->free_data = [](function_record *r) { ((capture *) &r->data)->~capture(); };
} else {
rec->data[0] = new capture { std::forward<Func>(f) };
rec->free_data = [](function_record *r) { delete ((capture *) r->data[0]); };
}
/* Type casters for the function arguments and return value */
using cast_in = argument_loader<Args...>;
using cast_out = make_caster<
conditional_t<std::is_void<Return>::value, void_type, Return>
>;
static_assert(expected_num_args<Extra...>(sizeof...(Args), cast_in::has_args, cast_in::has_kwargs),
"The number of argument annotations does not match the number of function arguments");
/* Dispatch code which converts function arguments and performs the actual function call */
rec->impl = [](function_call &call) -> handle {
cast_in args_converter;
/* Try to cast the function arguments into the C++ domain */
if (!args_converter.load_args(call))
return PYBIND11_TRY_NEXT_OVERLOAD;
/* Invoke call policy pre-call hook */
process_attributes<Extra...>::precall(call);
/* Get a pointer to the capture object */
auto data = (sizeof(capture) <= sizeof(call.func.data)
? &call.func.data : call.func.data[0]);
capture *cap = const_cast<capture *>(reinterpret_cast<const capture *>(data));
/* Override policy for rvalues -- usually to enforce rvp::move on an rvalue */
return_value_policy policy = return_value_policy_override<Return>::policy(call.func.policy);
/* Function scope guard -- defaults to the compile-to-nothing `void_type` */
using Guard = extract_guard_t<Extra...>;
/* Perform the function call */
handle result = cast_out::cast(
std::move(args_converter).template call<Return, Guard>(cap->f), policy, call.parent);
/* Invoke call policy post-call hook */
process_attributes<Extra...>::postcall(call, result);
return result;
};
/* Process any user-provided function attributes */
process_attributes<Extra...>::init(extra..., rec);
/* Generate a readable signature describing the function's arguments and return value types */
static constexpr auto signature = _("(") + cast_in::arg_names + _(") -> ") + cast_out::name;
PYBIND11_DESCR_CONSTEXPR auto types = decltype(signature)::types();
/* Register the function with Python from generic (non-templated) code */
initialize_generic(rec, signature.text, types.data(), sizeof...(Args));
if (cast_in::has_args) rec->has_args = true;
if (cast_in::has_kwargs) rec->has_kwargs = true;
/* Stash some additional information used by an important optimization in 'functional.h' */
using FunctionType = Return (*)(Args...);
constexpr bool is_function_ptr =
std::is_convertible<Func, FunctionType>::value &&
sizeof(capture) == sizeof(void *);
if (is_function_ptr) {
rec->is_stateless = true;
rec->data[1] = const_cast<void *>(reinterpret_cast<const void *>(&typeid(FunctionType)));
}
}
/// Register a function call with Python (generic non-templated code goes here)
void initialize_generic(detail::function_record *rec, const char *text,
const std::type_info *const *types, size_t args) {
/* Create copies of all referenced C-style strings */
rec->name = strdup(rec->name ? rec->name : "");
if (rec->doc) rec->doc = strdup(rec->doc);
for (auto &a: rec->args) {
if (a.name)
a.name = strdup(a.name);
if (a.descr)
a.descr = strdup(a.descr);
else if (a.value)
a.descr = strdup(a.value.attr("__repr__")().cast<std::string>().c_str());
}
rec->is_constructor = !strcmp(rec->name, "__init__") || !strcmp(rec->name, "__setstate__");
#if !defined(NDEBUG) && !defined(PYBIND11_DISABLE_NEW_STYLE_INIT_WARNING)
if (rec->is_constructor && !rec->is_new_style_constructor) {
const auto class_name = std::string(((PyTypeObject *) rec->scope.ptr())->tp_name);
const auto func_name = std::string(rec->name);
PyErr_WarnEx(
PyExc_FutureWarning,
("pybind11-bound class '" + class_name + "' is using an old-style "
"placement-new '" + func_name + "' which has been deprecated. See "
"the upgrade guide in pybind11's docs. This message is only visible "
"when compiled in debug mode.").c_str(), 0
);
}
#endif
/* Generate a proper function signature */
std::string signature;
size_t type_index = 0, arg_index = 0;
for (auto *pc = text; *pc != '\0'; ++pc) {
const auto c = *pc;
if (c == '{') {
// Write arg name for everything except *args and **kwargs.
if (*(pc + 1) == '*')
continue;
if (arg_index < rec->args.size() && rec->args[arg_index].name) {
signature += rec->args[arg_index].name;
} else if (arg_index == 0 && rec->is_method) {
signature += "self";
} else {
signature += "arg" + std::to_string(arg_index - (rec->is_method ? 1 : 0));
}
signature += ": ";
} else if (c == '}') {
// Write default value if available.
if (arg_index < rec->args.size() && rec->args[arg_index].descr) {
signature += " = ";
signature += rec->args[arg_index].descr;
}
arg_index++;
} else if (c == '%') {
const std::type_info *t = types[type_index++];
if (!t)
pybind11_fail("Internal error while parsing type signature (1)");
if (auto tinfo = detail::get_type_info(*t)) {
handle th((PyObject *) tinfo->type);
signature +=
th.attr("__module__").cast<std::string>() + "." +
th.attr("__qualname__").cast<std::string>(); // Python 3.3+, but we backport it to earlier versions
} else if (rec->is_new_style_constructor && arg_index == 0) {
// A new-style `__init__` takes `self` as `value_and_holder`.
// Rewrite it to the proper class type.
signature +=
rec->scope.attr("__module__").cast<std::string>() + "." +
rec->scope.attr("__qualname__").cast<std::string>();
} else {
std::string tname(t->name());
detail::clean_type_id(tname);
signature += tname;
}
} else {
signature += c;
}
}
if (arg_index != args || types[type_index] != nullptr)
pybind11_fail("Internal error while parsing type signature (2)");
#if PY_MAJOR_VERSION < 3
if (strcmp(rec->name, "__next__") == 0) {
std::free(rec->name);
rec->name = strdup("next");
} else if (strcmp(rec->name, "__bool__") == 0) {
std::free(rec->name);
rec->name = strdup("__nonzero__");
}
#endif
rec->signature = strdup(signature.c_str());
rec->args.shrink_to_fit();
rec->nargs = (std::uint16_t) args;
if (rec->sibling && PYBIND11_INSTANCE_METHOD_CHECK(rec->sibling.ptr()))
rec->sibling = PYBIND11_INSTANCE_METHOD_GET_FUNCTION(rec->sibling.ptr());
detail::function_record *chain = nullptr, *chain_start = rec;
if (rec->sibling) {
if (PyCFunction_Check(rec->sibling.ptr())) {
auto rec_capsule = reinterpret_borrow<capsule>(PyCFunction_GET_SELF(rec->sibling.ptr()));
chain = (detail::function_record *) rec_capsule;
/* Never append a method to an overload chain of a parent class;
instead, hide the parent's overloads in this case */
if (!chain->scope.is(rec->scope))
chain = nullptr;
}
// Don't trigger for things like the default __init__, which are wrapper_descriptors that we are intentionally replacing
else if (!rec->sibling.is_none() && rec->name[0] != '_')
pybind11_fail("Cannot overload existing non-function object \"" + std::string(rec->name) +
"\" with a function of the same name");
}
if (!chain) {
/* No existing overload was found, create a new function object */
rec->def = new PyMethodDef();
std::memset(rec->def, 0, sizeof(PyMethodDef));
rec->def->ml_name = rec->name;
rec->def->ml_meth = reinterpret_cast<PyCFunction>(reinterpret_cast<void (*) (void)>(*dispatcher));
rec->def->ml_flags = METH_VARARGS | METH_KEYWORDS;
capsule rec_capsule(rec, [](void *ptr) {
destruct((detail::function_record *) ptr);
});
object scope_module;
if (rec->scope) {
if (hasattr(rec->scope, "__module__")) {
scope_module = rec->scope.attr("__module__");
} else if (hasattr(rec->scope, "__name__")) {
scope_module = rec->scope.attr("__name__");
}
}
m_ptr = PyCFunction_NewEx(rec->def, rec_capsule.ptr(), scope_module.ptr());
if (!m_ptr)
pybind11_fail("cpp_function::cpp_function(): Could not allocate function object");
} else {
/* Append at the end of the overload chain */
m_ptr = rec->sibling.ptr();
inc_ref();
chain_start = chain;
if (chain->is_method != rec->is_method)
pybind11_fail("overloading a method with both static and instance methods is not supported; "
#if defined(NDEBUG)
"compile in debug mode for more details"
#else
"error while attempting to bind " + std::string(rec->is_method ? "instance" : "static") + " method " +
std::string(pybind11::str(rec->scope.attr("__name__"))) + "." + std::string(rec->name) + signature
#endif
);
while (chain->next)
chain = chain->next;
chain->next = rec;
}
std::string signatures;
int index = 0;
/* Create a nice pydoc rec including all signatures and
docstrings of the functions in the overload chain */
if (chain && options::show_function_signatures()) {
// First a generic signature
signatures += rec->name;
signatures += "(*args, **kwargs)\n";
signatures += "Overloaded function.\n\n";
}
// Then specific overload signatures
bool first_user_def = true;
for (auto it = chain_start; it != nullptr; it = it->next) {
if (options::show_function_signatures()) {
if (index > 0) signatures += "\n";
if (chain)
signatures += std::to_string(++index) + ". ";
signatures += rec->name;
signatures += it->signature;
signatures += "\n";
}
if (it->doc && strlen(it->doc) > 0 && options::show_user_defined_docstrings()) {
// If we're appending another docstring, and aren't printing function signatures, we
// need to append a newline first:
if (!options::show_function_signatures()) {
if (first_user_def) first_user_def = false;
else signatures += "\n";
}
if (options::show_function_signatures()) signatures += "\n";
signatures += it->doc;
if (options::show_function_signatures()) signatures += "\n";
}
}
/* Install docstring */
PyCFunctionObject *func = (PyCFunctionObject *) m_ptr;
if (func->m_ml->ml_doc)
std::free(const_cast<char *>(func->m_ml->ml_doc));
func->m_ml->ml_doc = strdup(signatures.c_str());
if (rec->is_method) {
m_ptr = PYBIND11_INSTANCE_METHOD_NEW(m_ptr, rec->scope.ptr());
if (!m_ptr)
pybind11_fail("cpp_function::cpp_function(): Could not allocate instance method object");
Py_DECREF(func);
}
}
/// When a cpp_function is GCed, release any memory allocated by pybind11
static void destruct(detail::function_record *rec) {
while (rec) {
detail::function_record *next = rec->next;
if (rec->free_data)
rec->free_data(rec);
std::free((char *) rec->name);
std::free((char *) rec->doc);
std::free((char *) rec->signature);
for (auto &arg: rec->args) {
std::free(const_cast<char *>(arg.name));
std::free(const_cast<char *>(arg.descr));
arg.value.dec_ref();
}
if (rec->def) {
std::free(const_cast<char *>(rec->def->ml_doc));
delete rec->def;
}
delete rec;
rec = next;
}
}
/// Main dispatch logic for calls to functions bound using pybind11
static PyObject *dispatcher(PyObject *self, PyObject *args_in, PyObject *kwargs_in) {
using namespace detail;
/* Iterator over the list of potentially admissible overloads */
const function_record *overloads = (function_record *) PyCapsule_GetPointer(self, nullptr),
*it = overloads;
/* Need to know how many arguments + keyword arguments there are to pick the right overload */
const size_t n_args_in = (size_t) PyTuple_GET_SIZE(args_in);
handle parent = n_args_in > 0 ? PyTuple_GET_ITEM(args_in, 0) : nullptr,
result = PYBIND11_TRY_NEXT_OVERLOAD;
auto self_value_and_holder = value_and_holder();
if (overloads->is_constructor) {
const auto tinfo = get_type_info((PyTypeObject *) overloads->scope.ptr());
const auto pi = reinterpret_cast<instance *>(parent.ptr());
self_value_and_holder = pi->get_value_and_holder(tinfo, false);
if (!self_value_and_holder.type || !self_value_and_holder.inst) {
PyErr_SetString(PyExc_TypeError, "__init__(self, ...) called with invalid `self` argument");
return nullptr;
}
// If this value is already registered it must mean __init__ is invoked multiple times;
// we really can't support that in C++, so just ignore the second __init__.
if (self_value_and_holder.instance_registered())
return none().release().ptr();
}
try {
// We do this in two passes: in the first pass, we load arguments with `convert=false`;
// in the second, we allow conversion (except for arguments with an explicit
// py::arg().noconvert()). This lets us prefer calls without conversion, with
// conversion as a fallback.
std::vector<function_call> second_pass;
// However, if there are no overloads, we can just skip the no-convert pass entirely
const bool overloaded = it != nullptr && it->next != nullptr;
for (; it != nullptr; it = it->next) {
/* For each overload:
1. Copy all positional arguments we were given, also checking to make sure that
named positional arguments weren't *also* specified via kwarg.
2. If we weren't given enough, try to make up the omitted ones by checking
whether they were provided by a kwarg matching the `py::arg("name")` name. If
so, use it (and remove it from kwargs; if not, see if the function binding
provided a default that we can use.
3. Ensure that either all keyword arguments were "consumed", or that the function
takes a kwargs argument to accept unconsumed kwargs.
4. Any positional arguments still left get put into a tuple (for args), and any
leftover kwargs get put into a dict.
5. Pack everything into a vector; if we have py::args or py::kwargs, they are an
extra tuple or dict at the end of the positional arguments.
6. Call the function call dispatcher (function_record::impl)
If one of these fail, move on to the next overload and keep trying until we get a
result other than PYBIND11_TRY_NEXT_OVERLOAD.
*/
const function_record &func = *it;
size_t pos_args = func.nargs; // Number of positional arguments that we need
if (func.has_args) --pos_args; // (but don't count py::args
if (func.has_kwargs) --pos_args; // or py::kwargs)
if (!func.has_args && n_args_in > pos_args)
continue; // Too many arguments for this overload
if (n_args_in < pos_args && func.args.size() < pos_args)
continue; // Not enough arguments given, and not enough defaults to fill in the blanks
function_call call(func, parent);
size_t args_to_copy = (std::min)(pos_args, n_args_in); // Protect std::min with parentheses
size_t args_copied = 0;
// 0. Inject new-style `self` argument
if (func.is_new_style_constructor) {
// The `value` may have been preallocated by an old-style `__init__`
// if it was a preceding candidate for overload resolution.
if (self_value_and_holder)
self_value_and_holder.type->dealloc(self_value_and_holder);
call.init_self = PyTuple_GET_ITEM(args_in, 0);
call.args.push_back(reinterpret_cast<PyObject *>(&self_value_and_holder));
call.args_convert.push_back(false);
++args_copied;
}
// 1. Copy any position arguments given.
bool bad_arg = false;
for (; args_copied < args_to_copy; ++args_copied) {
const argument_record *arg_rec = args_copied < func.args.size() ? &func.args[args_copied] : nullptr;
if (kwargs_in && arg_rec && arg_rec->name && PyDict_GetItemString(kwargs_in, arg_rec->name)) {
bad_arg = true;
break;
}
handle arg(PyTuple_GET_ITEM(args_in, args_copied));
if (arg_rec && !arg_rec->none && arg.is_none()) {
bad_arg = true;
break;
}
call.args.push_back(arg);
call.args_convert.push_back(arg_rec ? arg_rec->convert : true);
}
if (bad_arg)
continue; // Maybe it was meant for another overload (issue #688)
// We'll need to copy this if we steal some kwargs for defaults
dict kwargs = reinterpret_borrow<dict>(kwargs_in);
// 2. Check kwargs and, failing that, defaults that may help complete the list
if (args_copied < pos_args) {
bool copied_kwargs = false;
for (; args_copied < pos_args; ++args_copied) {
const auto &arg = func.args[args_copied];
handle value;
if (kwargs_in && arg.name)
value = PyDict_GetItemString(kwargs.ptr(), arg.name);
if (value) {
// Consume a kwargs value
if (!copied_kwargs) {
kwargs = reinterpret_steal<dict>(PyDict_Copy(kwargs.ptr()));
copied_kwargs = true;
}
PyDict_DelItemString(kwargs.ptr(), arg.name);
} else if (arg.value) {
value = arg.value;
}
if (value) {
call.args.push_back(value);
call.args_convert.push_back(arg.convert);
}
else
break;
}
if (args_copied < pos_args)
continue; // Not enough arguments, defaults, or kwargs to fill the positional arguments
}
// 3. Check everything was consumed (unless we have a kwargs arg)
if (kwargs && kwargs.size() > 0 && !func.has_kwargs)
continue; // Unconsumed kwargs, but no py::kwargs argument to accept them
// 4a. If we have a py::args argument, create a new tuple with leftovers
if (func.has_args) {
tuple extra_args;
if (args_to_copy == 0) {
// We didn't copy out any position arguments from the args_in tuple, so we
// can reuse it directly without copying:
extra_args = reinterpret_borrow<tuple>(args_in);
} else if (args_copied >= n_args_in) {
extra_args = tuple(0);
} else {
size_t args_size = n_args_in - args_copied;
extra_args = tuple(args_size);
for (size_t i = 0; i < args_size; ++i) {
extra_args[i] = PyTuple_GET_ITEM(args_in, args_copied + i);
}
}
call.args.push_back(extra_args);
call.args_convert.push_back(false);
call.args_ref = std::move(extra_args);
}
// 4b. If we have a py::kwargs, pass on any remaining kwargs
if (func.has_kwargs) {
if (!kwargs.ptr())
kwargs = dict(); // If we didn't get one, send an empty one
call.args.push_back(kwargs);
call.args_convert.push_back(false);
call.kwargs_ref = std::move(kwargs);
}
// 5. Put everything in a vector. Not technically step 5, we've been building it
// in `call.args` all along.
#if !defined(NDEBUG)
if (call.args.size() != func.nargs || call.args_convert.size() != func.nargs)
pybind11_fail("Internal error: function call dispatcher inserted wrong number of arguments!");
#endif
std::vector<bool> second_pass_convert;
if (overloaded) {
// We're in the first no-convert pass, so swap out the conversion flags for a
// set of all-false flags. If the call fails, we'll swap the flags back in for
// the conversion-allowed call below.
second_pass_convert.resize(func.nargs, false);
call.args_convert.swap(second_pass_convert);
}
// 6. Call the function.
try {
loader_life_support guard{};
result = func.impl(call);
} catch (reference_cast_error &) {
result = PYBIND11_TRY_NEXT_OVERLOAD;
}
if (result.ptr() != PYBIND11_TRY_NEXT_OVERLOAD)
break;
if (overloaded) {
// The (overloaded) call failed; if the call has at least one argument that
// permits conversion (i.e. it hasn't been explicitly specified `.noconvert()`)
// then add this call to the list of second pass overloads to try.
for (size_t i = func.is_method ? 1 : 0; i < pos_args; i++) {
if (second_pass_convert[i]) {
// Found one: swap the converting flags back in and store the call for
// the second pass.
call.args_convert.swap(second_pass_convert);
second_pass.push_back(std::move(call));
break;
}
}
}
}
if (overloaded && !second_pass.empty() && result.ptr() == PYBIND11_TRY_NEXT_OVERLOAD) {
// The no-conversion pass finished without success, try again with conversion allowed
for (auto &call : second_pass) {
try {
loader_life_support guard{};
result = call.func.impl(call);
} catch (reference_cast_error &) {
result = PYBIND11_TRY_NEXT_OVERLOAD;
}
if (result.ptr() != PYBIND11_TRY_NEXT_OVERLOAD) {
// The error reporting logic below expects 'it' to be valid, as it would be
// if we'd encountered this failure in the first-pass loop.
if (!result)
it = &call.func;
break;
}
}
}
} catch (error_already_set &e) {
e.restore();
return nullptr;
#if defined(__GNUG__) && !defined(__clang__)
} catch ( abi::__forced_unwind& ) {
throw;
#endif
} catch (...) {
/* When an exception is caught, give each registered exception
translator a chance to translate it to a Python exception
in reverse order of registration.
A translator may choose to do one of the following:
- catch the exception and call PyErr_SetString or PyErr_SetObject
to set a standard (or custom) Python exception, or
- do nothing and let the exception fall through to the next translator, or
- delegate translation to the next translator by throwing a new type of exception. */
auto last_exception = std::current_exception();
auto &registered_exception_translators = get_internals().registered_exception_translators;
for (auto& translator : registered_exception_translators) {
try {
translator(last_exception);
} catch (...) {
last_exception = std::current_exception();
continue;
}
return nullptr;
}
PyErr_SetString(PyExc_SystemError, "Exception escaped from default exception translator!");
return nullptr;
}
auto append_note_if_missing_header_is_suspected = [](std::string &msg) {
if (msg.find("std::") != std::string::npos) {
msg += "\n\n"
"Did you forget to `#include <pybind11/stl.h>`? Or <pybind11/complex.h>,\n"
"<pybind11/functional.h>, <pybind11/chrono.h>, etc. Some automatic\n"
"conversions are optional and require extra headers to be included\n"
"when compiling your pybind11 module.";
}
};
if (result.ptr() == PYBIND11_TRY_NEXT_OVERLOAD) {
if (overloads->is_operator)
return handle(Py_NotImplemented).inc_ref().ptr();
std::string msg = std::string(overloads->name) + "(): incompatible " +
std::string(overloads->is_constructor ? "constructor" : "function") +
" arguments. The following argument types are supported:\n";
int ctr = 0;
for (const function_record *it2 = overloads; it2 != nullptr; it2 = it2->next) {
msg += " "+ std::to_string(++ctr) + ". ";
bool wrote_sig = false;
if (overloads->is_constructor) {
// For a constructor, rewrite `(self: Object, arg0, ...) -> NoneType` as `Object(arg0, ...)`
std::string sig = it2->signature;
size_t start = sig.find('(') + 7; // skip "(self: "
if (start < sig.size()) {
// End at the , for the next argument
size_t end = sig.find(", "), next = end + 2;
size_t ret = sig.rfind(" -> ");
// Or the ), if there is no comma:
if (end >= sig.size()) next = end = sig.find(')');
if (start < end && next < sig.size()) {
msg.append(sig, start, end - start);
msg += '(';
msg.append(sig, next, ret - next);
wrote_sig = true;
}
}
}
if (!wrote_sig) msg += it2->signature;
msg += "\n";
}
msg += "\nInvoked with: ";
auto args_ = reinterpret_borrow<tuple>(args_in);
bool some_args = false;
for (size_t ti = overloads->is_constructor ? 1 : 0; ti < args_.size(); ++ti) {
if (!some_args) some_args = true;
else msg += ", ";
msg += pybind11::repr(args_[ti]);
}
if (kwargs_in) {
auto kwargs = reinterpret_borrow<dict>(kwargs_in);
if (kwargs.size() > 0) {
if (some_args) msg += "; ";
msg += "kwargs: ";
bool first = true;
for (auto kwarg : kwargs) {
if (first) first = false;
else msg += ", ";
msg += pybind11::str("{}={!r}").format(kwarg.first, kwarg.second);
}
}
}
append_note_if_missing_header_is_suspected(msg);
PyErr_SetString(PyExc_TypeError, msg.c_str());
return nullptr;
} else if (!result) {
std::string msg = "Unable to convert function return value to a "
"Python type! The signature was\n\t";
msg += it->signature;
append_note_if_missing_header_is_suspected(msg);
PyErr_SetString(PyExc_TypeError, msg.c_str());
return nullptr;
} else {
if (overloads->is_constructor && !self_value_and_holder.holder_constructed()) {
auto *pi = reinterpret_cast<instance *>(parent.ptr());
self_value_and_holder.type->init_instance(pi, nullptr);
}
return result.ptr();
}
}
};
/// Wrapper for Python extension modules
class module : public object {
public:
PYBIND11_OBJECT_DEFAULT(module, object, PyModule_Check)
/// Create a new top-level Python module with the given name and docstring
explicit module(const char *name, const char *doc = nullptr) {
if (!options::show_user_defined_docstrings()) doc = nullptr;
#if PY_MAJOR_VERSION >= 3
PyModuleDef *def = new PyModuleDef();
std::memset(def, 0, sizeof(PyModuleDef));
def->m_name = name;
def->m_doc = doc;
def->m_size = -1;
Py_INCREF(def);
m_ptr = PyModule_Create(def);
#else
m_ptr = Py_InitModule3(name, nullptr, doc);
#endif
if (m_ptr == nullptr)
pybind11_fail("Internal error in module::module()");
inc_ref();
}
/** \rst
Create Python binding for a new function within the module scope. ``Func``
can be a plain C++ function, a function pointer, or a lambda function. For
details on the ``Extra&& ... extra`` argument, see section :ref:`extras`.
\endrst */
template <typename Func, typename... Extra>
module &def(const char *name_, Func &&f, const Extra& ... extra) {
cpp_function func(std::forward<Func>(f), name(name_), scope(*this),
sibling(getattr(*this, name_, none())), extra...);
// NB: allow overwriting here because cpp_function sets up a chain with the intention of
// overwriting (and has already checked internally that it isn't overwriting non-functions).
add_object(name_, func, true /* overwrite */);
return *this;
}
/** \rst
Create and return a new Python submodule with the given name and docstring.
This also works recursively, i.e.
.. code-block:: cpp
py::module m("example", "pybind11 example plugin");
py::module m2 = m.def_submodule("sub", "A submodule of 'example'");
py::module m3 = m2.def_submodule("subsub", "A submodule of 'example.sub'");
\endrst */
module def_submodule(const char *name, const char *doc = nullptr) {
std::string full_name = std::string(PyModule_GetName(m_ptr))
+ std::string(".") + std::string(name);
auto result = reinterpret_borrow<module>(PyImport_AddModule(full_name.c_str()));
if (doc && options::show_user_defined_docstrings())
result.attr("__doc__") = pybind11::str(doc);
attr(name) = result;
return result;
}
/// Import and return a module or throws `error_already_set`.
static module import(const char *name) {
PyObject *obj = PyImport_ImportModule(name);
if (!obj)
throw error_already_set();
return reinterpret_steal<module>(obj);
}
/// Reload the module or throws `error_already_set`.
void reload() {
PyObject *obj = PyImport_ReloadModule(ptr());
if (!obj)
throw error_already_set();
*this = reinterpret_steal<module>(obj);
}
// Adds an object to the module using the given name. Throws if an object with the given name
// already exists.
//
// overwrite should almost always be false: attempting to overwrite objects that pybind11 has
// established will, in most cases, break things.
PYBIND11_NOINLINE void add_object(const char *name, handle obj, bool overwrite = false) {
if (!overwrite && hasattr(*this, name))
pybind11_fail("Error during initialization: multiple incompatible definitions with name \"" +
std::string(name) + "\"");
PyModule_AddObject(ptr(), name, obj.inc_ref().ptr() /* steals a reference */);
}
};
/// \ingroup python_builtins
/// Return a dictionary representing the global variables in the current execution frame,
/// or ``__main__.__dict__`` if there is no frame (usually when the interpreter is embedded).
inline dict globals() {
PyObject *p = PyEval_GetGlobals();
return reinterpret_borrow<dict>(p ? p : module::import("__main__").attr("__dict__").ptr());
}
NAMESPACE_BEGIN(detail)
/// Generic support for creating new Python heap types
class generic_type : public object {
template <typename...> friend class class_;
public:
PYBIND11_OBJECT_DEFAULT(generic_type, object, PyType_Check)
protected:
void initialize(const type_record &rec) {
if (rec.scope && hasattr(rec.scope, rec.name))
pybind11_fail("generic_type: cannot initialize type \"" + std::string(rec.name) +
"\": an object with that name is already defined");
if (rec.module_local ? get_local_type_info(*rec.type) : get_global_type_info(*rec.type))
pybind11_fail("generic_type: type \"" + std::string(rec.name) +
"\" is already registered!");
m_ptr = make_new_python_type(rec);
/* Register supplemental type information in C++ dict */
auto *tinfo = new detail::type_info();
tinfo->type = (PyTypeObject *) m_ptr;
tinfo->cpptype = rec.type;
tinfo->type_size = rec.type_size;
tinfo->type_align = rec.type_align;
tinfo->operator_new = rec.operator_new;
tinfo->holder_size_in_ptrs = size_in_ptrs(rec.holder_size);
tinfo->init_instance = rec.init_instance;
tinfo->dealloc = rec.dealloc;
tinfo->simple_type = true;
tinfo->simple_ancestors = true;
tinfo->default_holder = rec.default_holder;
tinfo->module_local = rec.module_local;
auto &internals = get_internals();
auto tindex = std::type_index(*rec.type);
tinfo->direct_conversions = &internals.direct_conversions[tindex];
if (rec.module_local)
registered_local_types_cpp()[tindex] = tinfo;
else
internals.registered_types_cpp[tindex] = tinfo;
internals.registered_types_py[(PyTypeObject *) m_ptr] = { tinfo };
if (rec.bases.size() > 1 || rec.multiple_inheritance) {
mark_parents_nonsimple(tinfo->type);
tinfo->simple_ancestors = false;
}
else if (rec.bases.size() == 1) {
auto parent_tinfo = get_type_info((PyTypeObject *) rec.bases[0].ptr());
tinfo->simple_ancestors = parent_tinfo->simple_ancestors;
}
if (rec.module_local) {
// Stash the local typeinfo and loader so that external modules can access it.
tinfo->module_local_load = &type_caster_generic::local_load;
setattr(m_ptr, PYBIND11_MODULE_LOCAL_ID, capsule(tinfo));
}
}
/// Helper function which tags all parents of a type using mult. inheritance
void mark_parents_nonsimple(PyTypeObject *value) {
auto t = reinterpret_borrow<tuple>(value->tp_bases);
for (handle h : t) {
auto tinfo2 = get_type_info((PyTypeObject *) h.ptr());
if (tinfo2)
tinfo2->simple_type = false;
mark_parents_nonsimple((PyTypeObject *) h.ptr());
}
}
void install_buffer_funcs(
buffer_info *(*get_buffer)(PyObject *, void *),
void *get_buffer_data) {
PyHeapTypeObject *type = (PyHeapTypeObject*) m_ptr;
auto tinfo = detail::get_type_info(&type->ht_type);
if (!type->ht_type.tp_as_buffer)
pybind11_fail(
"To be able to register buffer protocol support for the type '" +
std::string(tinfo->type->tp_name) +
"' the associated class<>(..) invocation must "
"include the pybind11::buffer_protocol() annotation!");
tinfo->get_buffer = get_buffer;
tinfo->get_buffer_data = get_buffer_data;
}
// rec_func must be set for either fget or fset.
void def_property_static_impl(const char *name,
handle fget, handle fset,
detail::function_record *rec_func) {
const auto is_static = rec_func && !(rec_func->is_method && rec_func->scope);
const auto has_doc = rec_func && rec_func->doc && pybind11::options::show_user_defined_docstrings();
auto property = handle((PyObject *) (is_static ? get_internals().static_property_type
: &PyProperty_Type));
attr(name) = property(fget.ptr() ? fget : none(),
fset.ptr() ? fset : none(),
/*deleter*/none(),
pybind11::str(has_doc ? rec_func->doc : ""));
}
};
/// Set the pointer to operator new if it exists. The cast is needed because it can be overloaded.
template <typename T, typename = void_t<decltype(static_cast<void *(*)(size_t)>(T::operator new))>>
void set_operator_new(type_record *r) { r->operator_new = &T::operator new; }
template <typename> void set_operator_new(...) { }
template <typename T, typename SFINAE = void> struct has_operator_delete : std::false_type { };
template <typename T> struct has_operator_delete<T, void_t<decltype(static_cast<void (*)(void *)>(T::operator delete))>>
: std::true_type { };
template <typename T, typename SFINAE = void> struct has_operator_delete_size : std::false_type { };
template <typename T> struct has_operator_delete_size<T, void_t<decltype(static_cast<void (*)(void *, size_t)>(T::operator delete))>>
: std::true_type { };
/// Call class-specific delete if it exists or global otherwise. Can also be an overload set.
template <typename T, enable_if_t<has_operator_delete<T>::value, int> = 0>
void call_operator_delete(T *p, size_t, size_t) { T::operator delete(p); }
template <typename T, enable_if_t<!has_operator_delete<T>::value && has_operator_delete_size<T>::value, int> = 0>
void call_operator_delete(T *p, size_t s, size_t) { T::operator delete(p, s); }
inline void call_operator_delete(void *p, size_t s, size_t a) {
(void)s; (void)a;
#if defined(PYBIND11_CPP17)
if (a > __STDCPP_DEFAULT_NEW_ALIGNMENT__)
::operator delete(p, s, std::align_val_t(a));
else
::operator delete(p, s);
#else
::operator delete(p);
#endif
}
NAMESPACE_END(detail)
/// Given a pointer to a member function, cast it to its `Derived` version.
/// Forward everything else unchanged.
template <typename /*Derived*/, typename F>
auto method_adaptor(F &&f) -> decltype(std::forward<F>(f)) { return std::forward<F>(f); }
template <typename Derived, typename Return, typename Class, typename... Args>
auto method_adaptor(Return (Class::*pmf)(Args...)) -> Return (Derived::*)(Args...) {
static_assert(detail::is_accessible_base_of<Class, Derived>::value,
"Cannot bind an inaccessible base class method; use a lambda definition instead");
return pmf;
}
template <typename Derived, typename Return, typename Class, typename... Args>
auto method_adaptor(Return (Class::*pmf)(Args...) const) -> Return (Derived::*)(Args...) const {
static_assert(detail::is_accessible_base_of<Class, Derived>::value,
"Cannot bind an inaccessible base class method; use a lambda definition instead");
return pmf;
}
template <typename type_, typename... options>
class class_ : public detail::generic_type {
template <typename T> using is_holder = detail::is_holder_type<type_, T>;
template <typename T> using is_subtype = detail::is_strict_base_of<type_, T>;
template <typename T> using is_base = detail::is_strict_base_of<T, type_>;
// struct instead of using here to help MSVC:
template <typename T> struct is_valid_class_option :
detail::any_of<is_holder<T>, is_subtype<T>, is_base<T>> {};
public:
using type = type_;
using type_alias = detail::exactly_one_t<is_subtype, void, options...>;
constexpr static bool has_alias = !std::is_void<type_alias>::value;
using holder_type = detail::exactly_one_t<is_holder, std::unique_ptr<type>, options...>;
static_assert(detail::all_of<is_valid_class_option<options>...>::value,
"Unknown/invalid class_ template parameters provided");
static_assert(!has_alias || std::is_polymorphic<type>::value,
"Cannot use an alias class with a non-polymorphic type");
PYBIND11_OBJECT(class_, generic_type, PyType_Check)
template <typename... Extra>
class_(handle scope, const char *name, const Extra &... extra) {
using namespace detail;
// MI can only be specified via class_ template options, not constructor parameters
static_assert(
none_of<is_pyobject<Extra>...>::value || // no base class arguments, or:
( constexpr_sum(is_pyobject<Extra>::value...) == 1 && // Exactly one base
constexpr_sum(is_base<options>::value...) == 0 && // no template option bases
none_of<std::is_same<multiple_inheritance, Extra>...>::value), // no multiple_inheritance attr
"Error: multiple inheritance bases must be specified via class_ template options");
type_record record;
record.scope = scope;
record.name = name;
record.type = &typeid(type);
record.type_size = sizeof(conditional_t<has_alias, type_alias, type>);
record.type_align = alignof(conditional_t<has_alias, type_alias, type>&);
record.holder_size = sizeof(holder_type);
record.init_instance = init_instance;
record.dealloc = dealloc;
record.default_holder = detail::is_instantiation<std::unique_ptr, holder_type>::value;
set_operator_new<type>(&record);
/* Register base classes specified via template arguments to class_, if any */
PYBIND11_EXPAND_SIDE_EFFECTS(add_base<options>(record));
/* Process optional arguments, if any */
process_attributes<Extra...>::init(extra..., &record);
generic_type::initialize(record);
if (has_alias) {
auto &instances = record.module_local ? registered_local_types_cpp() : get_internals().registered_types_cpp;
instances[std::type_index(typeid(type_alias))] = instances[std::type_index(typeid(type))];
}
}
template <typename Base, detail::enable_if_t<is_base<Base>::value, int> = 0>
static void add_base(detail::type_record &rec) {
rec.add_base(typeid(Base), [](void *src) -> void * {
return static_cast<Base *>(reinterpret_cast<type *>(src));
});
}
template <typename Base, detail::enable_if_t<!is_base<Base>::value, int> = 0>
static void add_base(detail::type_record &) { }
template <typename Func, typename... Extra>
class_ &def(const char *name_, Func&& f, const Extra&... extra) {
cpp_function cf(method_adaptor<type>(std::forward<Func>(f)), name(name_), is_method(*this),
sibling(getattr(*this, name_, none())), extra...);
attr(cf.name()) = cf;
return *this;
}
template <typename Func, typename... Extra> class_ &
def_static(const char *name_, Func &&f, const Extra&... extra) {
static_assert(!std::is_member_function_pointer<Func>::value,
"def_static(...) called with a non-static member function pointer");
cpp_function cf(std::forward<Func>(f), name(name_), scope(*this),
sibling(getattr(*this, name_, none())), extra...);
attr(cf.name()) = staticmethod(cf);
return *this;
}
template <detail::op_id id, detail::op_type ot, typename L, typename R, typename... Extra>
class_ &def(const detail::op_<id, ot, L, R> &op, const Extra&... extra) {
op.execute(*this, extra...);
return *this;
}
template <detail::op_id id, detail::op_type ot, typename L, typename R, typename... Extra>
class_ & def_cast(const detail::op_<id, ot, L, R> &op, const Extra&... extra) {
op.execute_cast(*this, extra...);
return *this;
}
template <typename... Args, typename... Extra>
class_ &def(const detail::initimpl::constructor<Args...> &init, const Extra&... extra) {
init.execute(*this, extra...);
return *this;
}
template <typename... Args, typename... Extra>
class_ &def(const detail::initimpl::alias_constructor<Args...> &init, const Extra&... extra) {
init.execute(*this, extra...);
return *this;
}
template <typename... Args, typename... Extra>
class_ &def(detail::initimpl::factory<Args...> &&init, const Extra&... extra) {
std::move(init).execute(*this, extra...);
return *this;
}
template <typename... Args, typename... Extra>
class_ &def(detail::initimpl::pickle_factory<Args...> &&pf, const Extra &...extra) {
std::move(pf).execute(*this, extra...);
return *this;
}
template <typename Func> class_& def_buffer(Func &&func) {
struct capture { Func func; };
capture *ptr = new capture { std::forward<Func>(func) };
install_buffer_funcs([](PyObject *obj, void *ptr) -> buffer_info* {
detail::make_caster<type> caster;
if (!caster.load(obj, false))
return nullptr;
return new buffer_info(((capture *) ptr)->func(caster));
}, ptr);
return *this;
}
template <typename Return, typename Class, typename... Args>
class_ &def_buffer(Return (Class::*func)(Args...)) {
return def_buffer([func] (type &obj) { return (obj.*func)(); });
}
template <typename Return, typename Class, typename... Args>
class_ &def_buffer(Return (Class::*func)(Args...) const) {
return def_buffer([func] (const type &obj) { return (obj.*func)(); });
}
template <typename C, typename D, typename... Extra>
class_ &def_readwrite(const char *name, D C::*pm, const Extra&... extra) {
static_assert(std::is_same<C, type>::value || std::is_base_of<C, type>::value, "def_readwrite() requires a class member (or base class member)");
cpp_function fget([pm](const type &c) -> const D &{ return c.*pm; }, is_method(*this)),
fset([pm](type &c, const D &value) { c.*pm = value; }, is_method(*this));
def_property(name, fget, fset, return_value_policy::reference_internal, extra...);
return *this;
}
template <typename C, typename D, typename... Extra>
class_ &def_readonly(const char *name, const D C::*pm, const Extra& ...extra) {
static_assert(std::is_same<C, type>::value || std::is_base_of<C, type>::value, "def_readonly() requires a class member (or base class member)");
cpp_function fget([pm](const type &c) -> const D &{ return c.*pm; }, is_method(*this));
def_property_readonly(name, fget, return_value_policy::reference_internal, extra...);
return *this;
}
template <typename D, typename... Extra>
class_ &def_readwrite_static(const char *name, D *pm, const Extra& ...extra) {
cpp_function fget([pm](object) -> const D &{ return *pm; }, scope(*this)),
fset([pm](object, const D &value) { *pm = value; }, scope(*this));
def_property_static(name, fget, fset, return_value_policy::reference, extra...);
return *this;
}
template <typename D, typename... Extra>
class_ &def_readonly_static(const char *name, const D *pm, const Extra& ...extra) {
cpp_function fget([pm](object) -> const D &{ return *pm; }, scope(*this));
def_property_readonly_static(name, fget, return_value_policy::reference, extra...);
return *this;
}
/// Uses return_value_policy::reference_internal by default
template <typename Getter, typename... Extra>
class_ &def_property_readonly(const char *name, const Getter &fget, const Extra& ...extra) {
return def_property_readonly(name, cpp_function(method_adaptor<type>(fget)),
return_value_policy::reference_internal, extra...);
}
/// Uses cpp_function's return_value_policy by default
template <typename... Extra>
class_ &def_property_readonly(const char *name, const cpp_function &fget, const Extra& ...extra) {
return def_property(name, fget, nullptr, extra...);
}
/// Uses return_value_policy::reference by default
template <typename Getter, typename... Extra>
class_ &def_property_readonly_static(const char *name, const Getter &fget, const Extra& ...extra) {
return def_property_readonly_static(name, cpp_function(fget), return_value_policy::reference, extra...);
}
/// Uses cpp_function's return_value_policy by default
template <typename... Extra>
class_ &def_property_readonly_static(const char *name, const cpp_function &fget, const Extra& ...extra) {
return def_property_static(name, fget, nullptr, extra...);
}
/// Uses return_value_policy::reference_internal by default
template <typename Getter, typename Setter, typename... Extra>
class_ &def_property(const char *name, const Getter &fget, const Setter &fset, const Extra& ...extra) {
return def_property(name, fget, cpp_function(method_adaptor<type>(fset)), extra...);
}
template <typename Getter, typename... Extra>
class_ &def_property(const char *name, const Getter &fget, const cpp_function &fset, const Extra& ...extra) {
return def_property(name, cpp_function(method_adaptor<type>(fget)), fset,
return_value_policy::reference_internal, extra...);
}
/// Uses cpp_function's return_value_policy by default
template <typename... Extra>
class_ &def_property(const char *name, const cpp_function &fget, const cpp_function &fset, const Extra& ...extra) {
return def_property_static(name, fget, fset, is_method(*this), extra...);
}
/// Uses return_value_policy::reference by default
template <typename Getter, typename... Extra>
class_ &def_property_static(const char *name, const Getter &fget, const cpp_function &fset, const Extra& ...extra) {
return def_property_static(name, cpp_function(fget), fset, return_value_policy::reference, extra...);
}
/// Uses cpp_function's return_value_policy by default
template <typename... Extra>
class_ &def_property_static(const char *name, const cpp_function &fget, const cpp_function &fset, const Extra& ...extra) {
static_assert( 0 == detail::constexpr_sum(std::is_base_of<arg, Extra>::value...),
"Argument annotations are not allowed for properties");
auto rec_fget = get_function_record(fget), rec_fset = get_function_record(fset);
auto *rec_active = rec_fget;
if (rec_fget) {
char *doc_prev = rec_fget->doc; /* 'extra' field may include a property-specific documentation string */
detail::process_attributes<Extra...>::init(extra..., rec_fget);
if (rec_fget->doc && rec_fget->doc != doc_prev) {
free(doc_prev);
rec_fget->doc = strdup(rec_fget->doc);
}
}
if (rec_fset) {
char *doc_prev = rec_fset->doc;
detail::process_attributes<Extra...>::init(extra..., rec_fset);
if (rec_fset->doc && rec_fset->doc != doc_prev) {
free(doc_prev);
rec_fset->doc = strdup(rec_fset->doc);
}
if (! rec_active) rec_active = rec_fset;
}
def_property_static_impl(name, fget, fset, rec_active);
return *this;
}
private:
/// Initialize holder object, variant 1: object derives from enable_shared_from_this
template <typename T>
static void init_holder(detail::instance *inst, detail::value_and_holder &v_h,
const holder_type * /* unused */, const std::enable_shared_from_this<T> * /* dummy */) {
try {
auto sh = std::dynamic_pointer_cast<typename holder_type::element_type>(
v_h.value_ptr<type>()->shared_from_this());
if (sh) {
new (std::addressof(v_h.holder<holder_type>())) holder_type(std::move(sh));
v_h.set_holder_constructed();
}
} catch (const std::bad_weak_ptr &) {}
if (!v_h.holder_constructed() && inst->owned) {
new (std::addressof(v_h.holder<holder_type>())) holder_type(v_h.value_ptr<type>());
v_h.set_holder_constructed();
}
}
static void init_holder_from_existing(const detail::value_and_holder &v_h,
const holder_type *holder_ptr, std::true_type /*is_copy_constructible*/) {
new (std::addressof(v_h.holder<holder_type>())) holder_type(*reinterpret_cast<const holder_type *>(holder_ptr));
}
static void init_holder_from_existing(const detail::value_and_holder &v_h,
const holder_type *holder_ptr, std::false_type /*is_copy_constructible*/) {
new (std::addressof(v_h.holder<holder_type>())) holder_type(std::move(*const_cast<holder_type *>(holder_ptr)));
}
/// Initialize holder object, variant 2: try to construct from existing holder object, if possible
static void init_holder(detail::instance *inst, detail::value_and_holder &v_h,
const holder_type *holder_ptr, const void * /* dummy -- not enable_shared_from_this<T>) */) {
if (holder_ptr) {
init_holder_from_existing(v_h, holder_ptr, std::is_copy_constructible<holder_type>());
v_h.set_holder_constructed();
} else if (inst->owned || detail::always_construct_holder<holder_type>::value) {
new (std::addressof(v_h.holder<holder_type>())) holder_type(v_h.value_ptr<type>());
v_h.set_holder_constructed();
}
}
/// Performs instance initialization including constructing a holder and registering the known
/// instance. Should be called as soon as the `type` value_ptr is set for an instance. Takes an
/// optional pointer to an existing holder to use; if not specified and the instance is
/// `.owned`, a new holder will be constructed to manage the value pointer.
static void init_instance(detail::instance *inst, const void *holder_ptr) {
auto v_h = inst->get_value_and_holder(detail::get_type_info(typeid(type)));
if (!v_h.instance_registered()) {
register_instance(inst, v_h.value_ptr(), v_h.type);
v_h.set_instance_registered();
}
init_holder(inst, v_h, (const holder_type *) holder_ptr, v_h.value_ptr<type>());
}
/// Deallocates an instance; via holder, if constructed; otherwise via operator delete.
static void dealloc(detail::value_and_holder &v_h) {
if (v_h.holder_constructed()) {
v_h.holder<holder_type>().~holder_type();
v_h.set_holder_constructed(false);
}
else {
detail::call_operator_delete(v_h.value_ptr<type>(),
v_h.type->type_size,
v_h.type->type_align
);
}
v_h.value_ptr() = nullptr;
}
static detail::function_record *get_function_record(handle h) {
h = detail::get_function(h);
return h ? (detail::function_record *) reinterpret_borrow<capsule>(PyCFunction_GET_SELF(h.ptr()))
: nullptr;
}
};
/// Binds an existing constructor taking arguments Args...
template <typename... Args> detail::initimpl::constructor<Args...> init() { return {}; }
/// Like `init<Args...>()`, but the instance is always constructed through the alias class (even
/// when not inheriting on the Python side).
template <typename... Args> detail::initimpl::alias_constructor<Args...> init_alias() { return {}; }
/// Binds a factory function as a constructor
template <typename Func, typename Ret = detail::initimpl::factory<Func>>
Ret init(Func &&f) { return {std::forward<Func>(f)}; }
/// Dual-argument factory function: the first function is called when no alias is needed, the second
/// when an alias is needed (i.e. due to python-side inheritance). Arguments must be identical.
template <typename CFunc, typename AFunc, typename Ret = detail::initimpl::factory<CFunc, AFunc>>
Ret init(CFunc &&c, AFunc &&a) {
return {std::forward<CFunc>(c), std::forward<AFunc>(a)};
}
/// Binds pickling functions `__getstate__` and `__setstate__` and ensures that the type
/// returned by `__getstate__` is the same as the argument accepted by `__setstate__`.
template <typename GetState, typename SetState>
detail::initimpl::pickle_factory<GetState, SetState> pickle(GetState &&g, SetState &&s) {
return {std::forward<GetState>(g), std::forward<SetState>(s)};
}
NAMESPACE_BEGIN(detail)
struct enum_base {
enum_base(handle base, handle parent) : m_base(base), m_parent(parent) { }
PYBIND11_NOINLINE void init(bool is_arithmetic, bool is_convertible) {
m_base.attr("__entries") = dict();
auto property = handle((PyObject *) &PyProperty_Type);
auto static_property = handle((PyObject *) get_internals().static_property_type);
m_base.attr("__repr__") = cpp_function(
[](handle arg) -> str {
handle type = arg.get_type();
object type_name = type.attr("__name__");
dict entries = type.attr("__entries");
for (const auto &kv : entries) {
object other = kv.second[int_(0)];
if (other.equal(arg))
return pybind11::str("{}.{}").format(type_name, kv.first);
}
return pybind11::str("{}.???").format(type_name);
}, is_method(m_base)
);
m_base.attr("name") = property(cpp_function(
[](handle arg) -> str {
dict entries = arg.get_type().attr("__entries");
for (const auto &kv : entries) {
if (handle(kv.second[int_(0)]).equal(arg))
return pybind11::str(kv.first);
}
return "???";
}, is_method(m_base)
));
m_base.attr("__doc__") = static_property(cpp_function(
[](handle arg) -> std::string {
std::string docstring;
dict entries = arg.attr("__entries");
if (((PyTypeObject *) arg.ptr())->tp_doc)
docstring += std::string(((PyTypeObject *) arg.ptr())->tp_doc) + "\n\n";
docstring += "Members:";
for (const auto &kv : entries) {
auto key = std::string(pybind11::str(kv.first));
auto comment = kv.second[int_(1)];
docstring += "\n\n " + key;
if (!comment.is_none())
docstring += " : " + (std::string) pybind11::str(comment);
}
return docstring;
}
), none(), none(), "");
m_base.attr("__members__") = static_property(cpp_function(
[](handle arg) -> dict {
dict entries = arg.attr("__entries"), m;
for (const auto &kv : entries)
m[kv.first] = kv.second[int_(0)];
return m;
}), none(), none(), ""
);
#define PYBIND11_ENUM_OP_STRICT(op, expr, strict_behavior) \
m_base.attr(op) = cpp_function( \
[](object a, object b) { \
if (!a.get_type().is(b.get_type())) \
strict_behavior; \
return expr; \
}, \
is_method(m_base))
#define PYBIND11_ENUM_OP_CONV(op, expr) \
m_base.attr(op) = cpp_function( \
[](object a_, object b_) { \
int_ a(a_), b(b_); \
return expr; \
}, \
is_method(m_base))
#define PYBIND11_ENUM_OP_CONV_LHS(op, expr) \
m_base.attr(op) = cpp_function( \
[](object a_, object b) { \
int_ a(a_); \
return expr; \
}, \
is_method(m_base))
if (is_convertible) {
PYBIND11_ENUM_OP_CONV_LHS("__eq__", !b.is_none() && a.equal(b));
PYBIND11_ENUM_OP_CONV_LHS("__ne__", b.is_none() || !a.equal(b));
if (is_arithmetic) {
PYBIND11_ENUM_OP_CONV("__lt__", a < b);
PYBIND11_ENUM_OP_CONV("__gt__", a > b);
PYBIND11_ENUM_OP_CONV("__le__", a <= b);
PYBIND11_ENUM_OP_CONV("__ge__", a >= b);
PYBIND11_ENUM_OP_CONV("__and__", a & b);
PYBIND11_ENUM_OP_CONV("__rand__", a & b);
PYBIND11_ENUM_OP_CONV("__or__", a | b);
PYBIND11_ENUM_OP_CONV("__ror__", a | b);
PYBIND11_ENUM_OP_CONV("__xor__", a ^ b);
PYBIND11_ENUM_OP_CONV("__rxor__", a ^ b);
m_base.attr("__invert__") = cpp_function(
[](object arg) { return ~(int_(arg)); }, is_method(m_base));
}
} else {
PYBIND11_ENUM_OP_STRICT("__eq__", int_(a).equal(int_(b)), return false);
PYBIND11_ENUM_OP_STRICT("__ne__", !int_(a).equal(int_(b)), return true);
if (is_arithmetic) {
#define PYBIND11_THROW throw type_error("Expected an enumeration of matching type!");
PYBIND11_ENUM_OP_STRICT("__lt__", int_(a) < int_(b), PYBIND11_THROW);
PYBIND11_ENUM_OP_STRICT("__gt__", int_(a) > int_(b), PYBIND11_THROW);
PYBIND11_ENUM_OP_STRICT("__le__", int_(a) <= int_(b), PYBIND11_THROW);
PYBIND11_ENUM_OP_STRICT("__ge__", int_(a) >= int_(b), PYBIND11_THROW);
#undef PYBIND11_THROW
}
}
#undef PYBIND11_ENUM_OP_CONV_LHS
#undef PYBIND11_ENUM_OP_CONV
#undef PYBIND11_ENUM_OP_STRICT
object getstate = cpp_function(
[](object arg) { return int_(arg); }, is_method(m_base));
m_base.attr("__getstate__") = getstate;
m_base.attr("__hash__") = getstate;
}
PYBIND11_NOINLINE void value(char const* name_, object value, const char *doc = nullptr) {
dict entries = m_base.attr("__entries");
str name(name_);
if (entries.contains(name)) {
std::string type_name = (std::string) str(m_base.attr("__name__"));
throw value_error(type_name + ": element \"" + std::string(name_) + "\" already exists!");
}
entries[name] = std::make_pair(value, doc);
m_base.attr(name) = value;
}
PYBIND11_NOINLINE void export_values() {
dict entries = m_base.attr("__entries");
for (const auto &kv : entries)
m_parent.attr(kv.first) = kv.second[int_(0)];
}
handle m_base;
handle m_parent;
};
NAMESPACE_END(detail)
/// Binds C++ enumerations and enumeration classes to Python
template <typename Type> class enum_ : public class_<Type> {
public:
using Base = class_<Type>;
using Base::def;
using Base::attr;
using Base::def_property_readonly;
using Base::def_property_readonly_static;
using Scalar = typename std::underlying_type<Type>::type;
template <typename... Extra>
enum_(const handle &scope, const char *name, const Extra&... extra)
: class_<Type>(scope, name, extra...), m_base(*this, scope) {
constexpr bool is_arithmetic = detail::any_of<std::is_same<arithmetic, Extra>...>::value;
constexpr bool is_convertible = std::is_convertible<Type, Scalar>::value;
m_base.init(is_arithmetic, is_convertible);
def(init([](Scalar i) { return static_cast<Type>(i); }));
def("__int__", [](Type value) { return (Scalar) value; });
#if PY_MAJOR_VERSION < 3
def("__long__", [](Type value) { return (Scalar) value; });
#endif
#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 8
def("__index__", [](Type value) { return (Scalar) value; });
#endif
cpp_function setstate(
[](Type &value, Scalar arg) { value = static_cast<Type>(arg); },
is_method(*this));
attr("__setstate__") = setstate;
}
/// Export enumeration entries into the parent scope
enum_& export_values() {
m_base.export_values();
return *this;
}
/// Add an enumeration entry
enum_& value(char const* name, Type value, const char *doc = nullptr) {
m_base.value(name, pybind11::cast(value, return_value_policy::copy), doc);
return *this;
}
private:
detail::enum_base m_base;
};
NAMESPACE_BEGIN(detail)
inline void keep_alive_impl(handle nurse, handle patient) {
if (!nurse || !patient)
pybind11_fail("Could not activate keep_alive!");
if (patient.is_none() || nurse.is_none())
return; /* Nothing to keep alive or nothing to be kept alive by */
auto tinfo = all_type_info(Py_TYPE(nurse.ptr()));
if (!tinfo.empty()) {
/* It's a pybind-registered type, so we can store the patient in the
* internal list. */
add_patient(nurse.ptr(), patient.ptr());
}
else {
/* Fall back to clever approach based on weak references taken from
* Boost.Python. This is not used for pybind-registered types because
* the objects can be destroyed out-of-order in a GC pass. */
cpp_function disable_lifesupport(
[patient](handle weakref) { patient.dec_ref(); weakref.dec_ref(); });
weakref wr(nurse, disable_lifesupport);
patient.inc_ref(); /* reference patient and leak the weak reference */
(void) wr.release();
}
}
PYBIND11_NOINLINE inline void keep_alive_impl(size_t Nurse, size_t Patient, function_call &call, handle ret) {
auto get_arg = [&](size_t n) {
if (n == 0)
return ret;
else if (n == 1 && call.init_self)
return call.init_self;
else if (n <= call.args.size())
return call.args[n - 1];
return handle();
};
keep_alive_impl(get_arg(Nurse), get_arg(Patient));
}
inline std::pair<decltype(internals::registered_types_py)::iterator, bool> all_type_info_get_cache(PyTypeObject *type) {
auto res = get_internals().registered_types_py
#ifdef __cpp_lib_unordered_map_try_emplace
.try_emplace(type);
#else
.emplace(type, std::vector<detail::type_info *>());
#endif
if (res.second) {
// New cache entry created; set up a weak reference to automatically remove it if the type
// gets destroyed:
weakref((PyObject *) type, cpp_function([type](handle wr) {
get_internals().registered_types_py.erase(type);
wr.dec_ref();
})).release();
}
return res;
}
template <typename Iterator, typename Sentinel, bool KeyIterator, return_value_policy Policy>
struct iterator_state {
Iterator it;
Sentinel end;
bool first_or_done;
};
NAMESPACE_END(detail)
/// Makes a python iterator from a first and past-the-end C++ InputIterator.
template <return_value_policy Policy = return_value_policy::reference_internal,
typename Iterator,
typename Sentinel,
typename ValueType = decltype(*std::declval<Iterator>()),
typename... Extra>
iterator make_iterator(Iterator first, Sentinel last, Extra &&... extra) {
typedef detail::iterator_state<Iterator, Sentinel, false, Policy> state;
if (!detail::get_type_info(typeid(state), false)) {
class_<state>(handle(), "iterator", pybind11::module_local())
.def("__iter__", [](state &s) -> state& { return s; })
.def("__next__", [](state &s) -> ValueType {
if (!s.first_or_done)
++s.it;
else
s.first_or_done = false;
if (s.it == s.end) {
s.first_or_done = true;
throw stop_iteration();
}
return *s.it;
}, std::forward<Extra>(extra)..., Policy);
}
return cast(state{first, last, true});
}
/// Makes an python iterator over the keys (`.first`) of a iterator over pairs from a
/// first and past-the-end InputIterator.
template <return_value_policy Policy = return_value_policy::reference_internal,
typename Iterator,
typename Sentinel,
typename KeyType = decltype((*std::declval<Iterator>()).first),
typename... Extra>
iterator make_key_iterator(Iterator first, Sentinel last, Extra &&... extra) {
typedef detail::iterator_state<Iterator, Sentinel, true, Policy> state;
if (!detail::get_type_info(typeid(state), false)) {
class_<state>(handle(), "iterator", pybind11::module_local())
.def("__iter__", [](state &s) -> state& { return s; })
.def("__next__", [](state &s) -> KeyType {
if (!s.first_or_done)
++s.it;
else
s.first_or_done = false;
if (s.it == s.end) {
s.first_or_done = true;
throw stop_iteration();
}
return (*s.it).first;
}, std::forward<Extra>(extra)..., Policy);
}
return cast(state{first, last, true});
}
/// Makes an iterator over values of an stl container or other container supporting
/// `std::begin()`/`std::end()`
template <return_value_policy Policy = return_value_policy::reference_internal,
typename Type, typename... Extra> iterator make_iterator(Type &value, Extra&&... extra) {
return make_iterator<Policy>(std::begin(value), std::end(value), extra...);
}
/// Makes an iterator over the keys (`.first`) of a stl map-like container supporting
/// `std::begin()`/`std::end()`
template <return_value_policy Policy = return_value_policy::reference_internal,
typename Type, typename... Extra> iterator make_key_iterator(Type &value, Extra&&... extra) {
return make_key_iterator<Policy>(std::begin(value), std::end(value), extra...);
}
template <typename InputType, typename OutputType> void implicitly_convertible() {
struct set_flag {
bool &flag;
set_flag(bool &flag) : flag(flag) { flag = true; }
~set_flag() { flag = false; }
};
auto implicit_caster = [](PyObject *obj, PyTypeObject *type) -> PyObject * {
static bool currently_used = false;
if (currently_used) // implicit conversions are non-reentrant
return nullptr;
set_flag flag_helper(currently_used);
if (!detail::make_caster<InputType>().load(obj, false))
return nullptr;
tuple args(1);
args[0] = obj;
PyObject *result = PyObject_Call((PyObject *) type, args.ptr(), nullptr);
if (result == nullptr)
PyErr_Clear();
return result;
};
if (auto tinfo = detail::get_type_info(typeid(OutputType)))
tinfo->implicit_conversions.push_back(implicit_caster);
else
pybind11_fail("implicitly_convertible: Unable to find type " + type_id<OutputType>());
}
template <typename ExceptionTranslator>
void register_exception_translator(ExceptionTranslator&& translator) {
detail::get_internals().registered_exception_translators.push_front(
std::forward<ExceptionTranslator>(translator));
}
/**
* Wrapper to generate a new Python exception type.
*
* This should only be used with PyErr_SetString for now.
* It is not (yet) possible to use as a py::base.
* Template type argument is reserved for future use.
*/
template <typename type>
class exception : public object {
public:
exception() = default;
exception(handle scope, const char *name, PyObject *base = PyExc_Exception) {
std::string full_name = scope.attr("__name__").cast<std::string>() +
std::string(".") + name;
m_ptr = PyErr_NewException(const_cast<char *>(full_name.c_str()), base, NULL);
if (hasattr(scope, name))
pybind11_fail("Error during initialization: multiple incompatible "
"definitions with name \"" + std::string(name) + "\"");
scope.attr(name) = *this;
}
// Sets the current python exception to this exception object with the given message
void operator()(const char *message) {
PyErr_SetString(m_ptr, message);
}
};
NAMESPACE_BEGIN(detail)
// Returns a reference to a function-local static exception object used in the simple
// register_exception approach below. (It would be simpler to have the static local variable
// directly in register_exception, but that makes clang <3.5 segfault - issue #1349).
template <typename CppException>
exception<CppException> &get_exception_object() { static exception<CppException> ex; return ex; }
NAMESPACE_END(detail)
/**
* Registers a Python exception in `m` of the given `name` and installs an exception translator to
* translate the C++ exception to the created Python exception using the exceptions what() method.
* This is intended for simple exception translations; for more complex translation, register the
* exception object and translator directly.
*/
template <typename CppException>
exception<CppException> &register_exception(handle scope,
const char *name,
PyObject *base = PyExc_Exception) {
auto &ex = detail::get_exception_object<CppException>();
if (!ex) ex = exception<CppException>(scope, name, base);
register_exception_translator([](std::exception_ptr p) {
if (!p) return;
try {
std::rethrow_exception(p);
} catch (const CppException &e) {
detail::get_exception_object<CppException>()(e.what());
}
});
return ex;
}
NAMESPACE_BEGIN(detail)
PYBIND11_NOINLINE inline void print(tuple args, dict kwargs) {
auto strings = tuple(args.size());
for (size_t i = 0; i < args.size(); ++i) {
strings[i] = str(args[i]);
}
auto sep = kwargs.contains("sep") ? kwargs["sep"] : cast(" ");
auto line = sep.attr("join")(strings);
object file;
if (kwargs.contains("file")) {
file = kwargs["file"].cast<object>();
} else {
try {
file = module::import("sys").attr("stdout");
} catch (const error_already_set &) {
/* If print() is called from code that is executed as
part of garbage collection during interpreter shutdown,
importing 'sys' can fail. Give up rather than crashing the
interpreter in this case. */
return;
}
}
auto write = file.attr("write");
write(line);
write(kwargs.contains("end") ? kwargs["end"] : cast("\n"));
if (kwargs.contains("flush") && kwargs["flush"].cast<bool>())
file.attr("flush")();
}
NAMESPACE_END(detail)
template <return_value_policy policy = return_value_policy::automatic_reference, typename... Args>
void print(Args &&...args) {
auto c = detail::collect_arguments<policy>(std::forward<Args>(args)...);
detail::print(c.args(), c.kwargs());
}
#if defined(WITH_THREAD) && !defined(PYPY_VERSION)
/* The functions below essentially reproduce the PyGILState_* API using a RAII
* pattern, but there are a few important differences:
*
* 1. When acquiring the GIL from an non-main thread during the finalization
* phase, the GILState API blindly terminates the calling thread, which
* is often not what is wanted. This API does not do this.
*
* 2. The gil_scoped_release function can optionally cut the relationship
* of a PyThreadState and its associated thread, which allows moving it to
* another thread (this is a fairly rare/advanced use case).
*
* 3. The reference count of an acquired thread state can be controlled. This
* can be handy to prevent cases where callbacks issued from an external
* thread would otherwise constantly construct and destroy thread state data
* structures.
*
* See the Python bindings of NanoGUI (http://github.com/wjakob/nanogui) for an
* example which uses features 2 and 3 to migrate the Python thread of
* execution to another thread (to run the event loop on the original thread,
* in this case).
*/
class gil_scoped_acquire {
public:
PYBIND11_NOINLINE gil_scoped_acquire() {
auto const &internals = detail::get_internals();
tstate = (PyThreadState *) PYBIND11_TLS_GET_VALUE(internals.tstate);
if (!tstate) {
/* Check if the GIL was acquired using the PyGILState_* API instead (e.g. if
calling from a Python thread). Since we use a different key, this ensures
we don't create a new thread state and deadlock in PyEval_AcquireThread
below. Note we don't save this state with internals.tstate, since we don't
create it we would fail to clear it (its reference count should be > 0). */
tstate = PyGILState_GetThisThreadState();
}
if (!tstate) {
tstate = PyThreadState_New(internals.istate);
#if !defined(NDEBUG)
if (!tstate)
pybind11_fail("scoped_acquire: could not create thread state!");
#endif
tstate->gilstate_counter = 0;
PYBIND11_TLS_REPLACE_VALUE(internals.tstate, tstate);
} else {
release = detail::get_thread_state_unchecked() != tstate;
}
if (release) {
/* Work around an annoying assertion in PyThreadState_Swap */
#if defined(Py_DEBUG)
PyInterpreterState *interp = tstate->interp;
tstate->interp = nullptr;
#endif
PyEval_AcquireThread(tstate);
#if defined(Py_DEBUG)
tstate->interp = interp;
#endif
}
inc_ref();
}
void inc_ref() {
++tstate->gilstate_counter;
}
PYBIND11_NOINLINE void dec_ref() {
--tstate->gilstate_counter;
#if !defined(NDEBUG)
if (detail::get_thread_state_unchecked() != tstate)
pybind11_fail("scoped_acquire::dec_ref(): thread state must be current!");
if (tstate->gilstate_counter < 0)
pybind11_fail("scoped_acquire::dec_ref(): reference count underflow!");
#endif
if (tstate->gilstate_counter == 0) {
#if !defined(NDEBUG)
if (!release)
pybind11_fail("scoped_acquire::dec_ref(): internal error!");
#endif
PyThreadState_Clear(tstate);
PyThreadState_DeleteCurrent();
PYBIND11_TLS_DELETE_VALUE(detail::get_internals().tstate);
release = false;
}
}
PYBIND11_NOINLINE ~gil_scoped_acquire() {
dec_ref();
if (release)
PyEval_SaveThread();
}
private:
PyThreadState *tstate = nullptr;
bool release = true;
};
class gil_scoped_release {
public:
explicit gil_scoped_release(bool disassoc = false) : disassoc(disassoc) {
// `get_internals()` must be called here unconditionally in order to initialize
// `internals.tstate` for subsequent `gil_scoped_acquire` calls. Otherwise, an
// initialization race could occur as multiple threads try `gil_scoped_acquire`.
const auto &internals = detail::get_internals();
tstate = PyEval_SaveThread();
if (disassoc) {
auto key = internals.tstate;
PYBIND11_TLS_DELETE_VALUE(key);
}
}
~gil_scoped_release() {
if (!tstate)
return;
PyEval_RestoreThread(tstate);
if (disassoc) {
auto key = detail::get_internals().tstate;
PYBIND11_TLS_REPLACE_VALUE(key, tstate);
}
}
private:
PyThreadState *tstate;
bool disassoc;
};
#elif defined(PYPY_VERSION)
class gil_scoped_acquire {
PyGILState_STATE state;
public:
gil_scoped_acquire() { state = PyGILState_Ensure(); }
~gil_scoped_acquire() { PyGILState_Release(state); }
};
class gil_scoped_release {
PyThreadState *state;
public:
gil_scoped_release() { state = PyEval_SaveThread(); }
~gil_scoped_release() { PyEval_RestoreThread(state); }
};
#else
class gil_scoped_acquire { };
class gil_scoped_release { };
#endif
error_already_set::~error_already_set() {
if (m_type) {
gil_scoped_acquire gil;
error_scope scope;
m_type.release().dec_ref();
m_value.release().dec_ref();
m_trace.release().dec_ref();
}
}
inline function get_type_overload(const void *this_ptr, const detail::type_info *this_type, const char *name) {
handle self = detail::get_object_handle(this_ptr, this_type);
if (!self)
return function();
handle type = self.get_type();
auto key = std::make_pair(type.ptr(), name);
/* Cache functions that aren't overloaded in Python to avoid
many costly Python dictionary lookups below */
auto &cache = detail::get_internals().inactive_overload_cache;
if (cache.find(key) != cache.end())
return function();
function overload = getattr(self, name, function());
if (overload.is_cpp_function()) {
cache.insert(key);
return function();
}
/* Don't call dispatch code if invoked from overridden function.
Unfortunately this doesn't work on PyPy. */
#if !defined(PYPY_VERSION)
PyFrameObject *frame = PyThreadState_Get()->frame;
if (frame && (std::string) str(frame->f_code->co_name) == name &&
frame->f_code->co_argcount > 0) {
PyFrame_FastToLocals(frame);
PyObject *self_caller = PyDict_GetItem(
frame->f_locals, PyTuple_GET_ITEM(frame->f_code->co_varnames, 0));
if (self_caller == self.ptr())
return function();
}
#else
/* PyPy currently doesn't provide a detailed cpyext emulation of
frame objects, so we have to emulate this using Python. This
is going to be slow..*/
dict d; d["self"] = self; d["name"] = pybind11::str(name);
PyObject *result = PyRun_String(
"import inspect\n"
"frame = inspect.currentframe()\n"
"if frame is not None:\n"
" frame = frame.f_back\n"
" if frame is not None and str(frame.f_code.co_name) == name and "
"frame.f_code.co_argcount > 0:\n"
" self_caller = frame.f_locals[frame.f_code.co_varnames[0]]\n"
" if self_caller == self:\n"
" self = None\n",
Py_file_input, d.ptr(), d.ptr());
if (result == nullptr)
throw error_already_set();
if (d["self"].is_none())
return function();
Py_DECREF(result);
#endif
return overload;
}
/** \rst
Try to retrieve a python method by the provided name from the instance pointed to by the this_ptr.
:this_ptr: The pointer to the object the overload should be retrieved for. This should be the first
non-trampoline class encountered in the inheritance chain.
:name: The name of the overloaded Python method to retrieve.
:return: The Python method by this name from the object or an empty function wrapper.
\endrst */
template <class T> function get_overload(const T *this_ptr, const char *name) {
auto tinfo = detail::get_type_info(typeid(T));
return tinfo ? get_type_overload(this_ptr, tinfo, name) : function();
}
#define PYBIND11_OVERLOAD_INT(ret_type, cname, name, ...) { \
pybind11::gil_scoped_acquire gil; \
pybind11::function overload = pybind11::get_overload(static_cast<const cname *>(this), name); \
if (overload) { \
auto o = overload(__VA_ARGS__); \
if (pybind11::detail::cast_is_temporary_value_reference<ret_type>::value) { \
static pybind11::detail::overload_caster_t<ret_type> caster; \
return pybind11::detail::cast_ref<ret_type>(std::move(o), caster); \
} \
else return pybind11::detail::cast_safe<ret_type>(std::move(o)); \
} \
}
/** \rst
Macro to populate the virtual method in the trampoline class. This macro tries to look up a method named 'fn'
from the Python side, deals with the :ref:`gil` and necessary argument conversions to call this method and return
the appropriate type. See :ref:`overriding_virtuals` for more information. This macro should be used when the method
name in C is not the same as the method name in Python. For example with `__str__`.
.. code-block:: cpp
std::string toString() override {
PYBIND11_OVERLOAD_NAME(
std::string, // Return type (ret_type)
Animal, // Parent class (cname)
toString, // Name of function in C++ (name)
"__str__", // Name of method in Python (fn)
);
}
\endrst */
#define PYBIND11_OVERLOAD_NAME(ret_type, cname, name, fn, ...) \
PYBIND11_OVERLOAD_INT(PYBIND11_TYPE(ret_type), PYBIND11_TYPE(cname), name, __VA_ARGS__) \
return cname::fn(__VA_ARGS__)
/** \rst
Macro for pure virtual functions, this function is identical to :c:macro:`PYBIND11_OVERLOAD_NAME`, except that it
throws if no overload can be found.
\endrst */
#define PYBIND11_OVERLOAD_PURE_NAME(ret_type, cname, name, fn, ...) \
PYBIND11_OVERLOAD_INT(PYBIND11_TYPE(ret_type), PYBIND11_TYPE(cname), name, __VA_ARGS__) \
pybind11::pybind11_fail("Tried to call pure virtual function \"" PYBIND11_STRINGIFY(cname) "::" name "\"");
/** \rst
Macro to populate the virtual method in the trampoline class. This macro tries to look up the method
from the Python side, deals with the :ref:`gil` and necessary argument conversions to call this method and return
the appropriate type. This macro should be used if the method name in C and in Python are identical.
See :ref:`overriding_virtuals` for more information.
.. code-block:: cpp
class PyAnimal : public Animal {
public:
// Inherit the constructors
using Animal::Animal;
// Trampoline (need one for each virtual function)
std::string go(int n_times) override {
PYBIND11_OVERLOAD_PURE(
std::string, // Return type (ret_type)
Animal, // Parent class (cname)
go, // Name of function in C++ (must match Python name) (fn)
n_times // Argument(s) (...)
);
}
};
\endrst */
#define PYBIND11_OVERLOAD(ret_type, cname, fn, ...) \
PYBIND11_OVERLOAD_NAME(PYBIND11_TYPE(ret_type), PYBIND11_TYPE(cname), #fn, fn, __VA_ARGS__)
/** \rst
Macro for pure virtual functions, this function is identical to :c:macro:`PYBIND11_OVERLOAD`, except that it throws
if no overload can be found.
\endrst */
#define PYBIND11_OVERLOAD_PURE(ret_type, cname, fn, ...) \
PYBIND11_OVERLOAD_PURE_NAME(PYBIND11_TYPE(ret_type), PYBIND11_TYPE(cname), #fn, fn, __VA_ARGS__)
NAMESPACE_END(PYBIND11_NAMESPACE)
#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
# pragma warning(pop)
#elif defined(__GNUG__) && !defined(__clang__)
# pragma GCC diagnostic pop
#endif