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668 lines
23 KiB
C++
668 lines
23 KiB
C++
2 months ago
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/* -*- indent-tabs-mode: nil; tab-width: 4; -*- */
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/**
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* Implementation of greenlet::UserGreenlet.
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*
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* Format with:
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* clang-format -i --style=file src/greenlet/greenlet.c
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*
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*
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* Fix missing braces with:
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* clang-tidy src/greenlet/greenlet.c -fix -checks="readability-braces-around-statements"
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*/
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#include "greenlet_internal.hpp"
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#include "greenlet_greenlet.hpp"
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#include "greenlet_thread_state.hpp"
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#include "TThreadStateDestroy.cpp"
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namespace greenlet {
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using greenlet::refs::BorrowedMainGreenlet;
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greenlet::PythonAllocator<UserGreenlet> UserGreenlet::allocator;
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void* UserGreenlet::operator new(size_t UNUSED(count))
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{
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return allocator.allocate(1);
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}
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void UserGreenlet::operator delete(void* ptr)
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{
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return allocator.deallocate(static_cast<UserGreenlet*>(ptr),
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1);
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}
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UserGreenlet::UserGreenlet(PyGreenlet* p, BorrowedGreenlet the_parent)
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: Greenlet(p), _parent(the_parent)
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{
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this->_self = p;
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}
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UserGreenlet::~UserGreenlet()
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{
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// Python 3.11: If we don't clear out the raw frame datastack
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// when deleting an unfinished greenlet,
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// TestLeaks.test_untracked_memory_doesnt_increase_unfinished_thread_dealloc_in_main fails.
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this->python_state.did_finish(nullptr);
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this->tp_clear();
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}
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BorrowedGreenlet
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UserGreenlet::self() const noexcept
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{
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return this->_self;
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}
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const BorrowedMainGreenlet
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UserGreenlet::main_greenlet() const
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{
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return this->_main_greenlet;
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}
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BorrowedMainGreenlet
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UserGreenlet::find_main_greenlet_in_lineage() const
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{
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if (this->started()) {
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assert(this->_main_greenlet);
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return BorrowedMainGreenlet(this->_main_greenlet);
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}
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if (!this->_parent) {
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/* garbage collected greenlet in chain */
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// XXX: WHAT?
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return BorrowedMainGreenlet(nullptr);
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}
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return this->_parent->find_main_greenlet_in_lineage();
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}
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/**
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* CAUTION: This will allocate memory and may trigger garbage
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* collection and arbitrary Python code.
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*/
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OwnedObject
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UserGreenlet::throw_GreenletExit_during_dealloc(const ThreadState& current_thread_state)
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{
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/* The dying greenlet cannot be a parent of ts_current
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because the 'parent' field chain would hold a
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reference */
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UserGreenlet::ParentIsCurrentGuard with_current_parent(this, current_thread_state);
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// We don't care about the return value, only whether an
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// exception happened. Whether or not an exception happens,
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// we need to restore the parent in case the greenlet gets
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// resurrected.
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return Greenlet::throw_GreenletExit_during_dealloc(current_thread_state);
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}
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ThreadState*
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UserGreenlet::thread_state() const noexcept
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{
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// TODO: maybe make this throw, if the thread state isn't there?
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// if (!this->main_greenlet) {
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// throw std::runtime_error("No thread state"); // TODO: Better exception
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// }
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if (!this->_main_greenlet) {
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return nullptr;
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}
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return this->_main_greenlet->thread_state();
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}
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bool
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UserGreenlet::was_running_in_dead_thread() const noexcept
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{
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return this->_main_greenlet && !this->thread_state();
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}
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OwnedObject
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UserGreenlet::g_switch()
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{
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assert(this->args() || PyErr_Occurred());
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try {
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this->check_switch_allowed();
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}
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catch (const PyErrOccurred&) {
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this->release_args();
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throw;
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}
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// Switching greenlets used to attempt to clean out ones that need
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// deleted *if* we detected a thread switch. Should it still do
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// that?
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// An issue is that if we delete a greenlet from another thread,
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// it gets queued to this thread, and ``kill_greenlet()`` switches
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// back into the greenlet
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/* find the real target by ignoring dead greenlets,
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and if necessary starting a greenlet. */
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switchstack_result_t err;
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Greenlet* target = this;
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// TODO: probably cleaner to handle the case where we do
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// switch to ourself separately from the other cases.
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// This can probably even further be simplified if we keep
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// track of the switching_state we're going for and just call
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// into g_switch() if it's not ourself. The main problem with that
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// is that we would be using more stack space.
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bool target_was_me = true;
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bool was_initial_stub = false;
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while (target) {
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if (target->active()) {
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if (!target_was_me) {
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target->args() <<= this->args();
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assert(!this->args());
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}
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err = target->g_switchstack();
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break;
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}
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if (!target->started()) {
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// We never encounter a main greenlet that's not started.
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assert(!target->main());
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UserGreenlet* real_target = static_cast<UserGreenlet*>(target);
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assert(real_target);
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void* dummymarker;
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was_initial_stub = true;
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if (!target_was_me) {
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target->args() <<= this->args();
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assert(!this->args());
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}
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try {
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// This can only throw back to us while we're
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// still in this greenlet. Once the new greenlet
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// is bootstrapped, it has its own exception state.
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err = real_target->g_initialstub(&dummymarker);
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}
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catch (const PyErrOccurred&) {
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this->release_args();
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throw;
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}
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catch (const GreenletStartedWhileInPython&) {
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// The greenlet was started sometime before this
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// greenlet actually switched to it, i.e.,
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// "concurrent" calls to switch() or throw().
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// We need to retry the switch.
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// Note that the current greenlet has been reset
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// to this one (or we wouldn't be running!)
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continue;
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}
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break;
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}
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target = target->parent();
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target_was_me = false;
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}
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// The ``this`` pointer and all other stack or register based
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// variables are invalid now, at least where things succeed
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// above.
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// But this one, probably not so much? It's not clear if it's
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// safe to throw an exception at this point.
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if (err.status < 0) {
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// If we get here, either g_initialstub()
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// failed, or g_switchstack() failed. Either one of those
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// cases SHOULD leave us in the original greenlet with a valid
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// stack.
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return this->on_switchstack_or_initialstub_failure(target, err, target_was_me, was_initial_stub);
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}
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// err.the_new_current_greenlet would be the same as ``target``,
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// if target wasn't probably corrupt.
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return err.the_new_current_greenlet->g_switch_finish(err);
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}
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Greenlet::switchstack_result_t
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UserGreenlet::g_initialstub(void* mark)
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{
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OwnedObject run;
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// We need to grab a reference to the current switch arguments
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// in case we're entered concurrently during the call to
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// GetAttr() and have to try again.
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// We'll restore them when we return in that case.
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// Scope them tightly to avoid ref leaks.
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{
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SwitchingArgs args(this->args());
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/* save exception in case getattr clears it */
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PyErrPieces saved;
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/*
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self.run is the object to call in the new greenlet.
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This could run arbitrary python code and switch greenlets!
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*/
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run = this->_self.PyRequireAttr(mod_globs->str_run);
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/* restore saved exception */
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saved.PyErrRestore();
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/* recheck that it's safe to switch in case greenlet reparented anywhere above */
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this->check_switch_allowed();
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/* by the time we got here another start could happen elsewhere,
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* that means it should now be a regular switch.
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* This can happen if the Python code is a subclass that implements
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* __getattribute__ or __getattr__, or makes ``run`` a descriptor;
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* all of those can run arbitrary code that switches back into
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* this greenlet.
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*/
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if (this->stack_state.started()) {
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// the successful switch cleared these out, we need to
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// restore our version. They will be copied on up to the
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// next target.
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assert(!this->args());
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this->args() <<= args;
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throw GreenletStartedWhileInPython();
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}
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}
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// Sweet, if we got here, we have the go-ahead and will switch
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// greenlets.
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// Nothing we do from here on out should allow for a thread or
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// greenlet switch: No arbitrary calls to Python, including
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// decref'ing
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#if GREENLET_USE_CFRAME
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/* OK, we need it, we're about to switch greenlets, save the state. */
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/*
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See green_new(). This is a stack-allocated variable used
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while *self* is in PyObject_Call().
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We want to defer copying the state info until we're sure
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we need it and are in a stable place to do so.
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*/
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_PyCFrame trace_info;
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this->python_state.set_new_cframe(trace_info);
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#endif
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/* start the greenlet */
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ThreadState& thread_state = GET_THREAD_STATE().state();
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this->stack_state = StackState(mark,
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thread_state.borrow_current()->stack_state);
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this->python_state.set_initial_state(PyThreadState_GET());
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this->exception_state.clear();
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this->_main_greenlet = thread_state.get_main_greenlet();
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/* perform the initial switch */
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switchstack_result_t err = this->g_switchstack();
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/* returns twice!
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The 1st time with ``err == 1``: we are in the new greenlet.
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This one owns a greenlet that used to be current.
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The 2nd time with ``err <= 0``: back in the caller's
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greenlet; this happens if the child finishes or switches
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explicitly to us. Either way, the ``err`` variable is
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created twice at the same memory location, but possibly
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having different ``origin`` values. Note that it's not
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constructed for the second time until the switch actually happens.
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*/
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if (err.status == 1) {
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// In the new greenlet.
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// This never returns! Calling inner_bootstrap steals
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// the contents of our run object within this stack frame, so
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// it is not valid to do anything with it.
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try {
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this->inner_bootstrap(err.origin_greenlet.relinquish_ownership(),
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run.relinquish_ownership());
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}
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// Getting a C++ exception here isn't good. It's probably a
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// bug in the underlying greenlet, meaning it's probably a
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// C++ extension. We're going to abort anyway, but try to
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// display some nice information *if* possible. Some obscure
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// platforms don't properly support this (old 32-bit Arm, see see
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// https://github.com/python-greenlet/greenlet/issues/385); that's not
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// great, but should usually be OK because, as mentioned above, we're
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// terminating anyway.
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//
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// The catching is tested by
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// ``test_cpp.CPPTests.test_unhandled_exception_in_greenlet_aborts``.
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//
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// PyErrOccurred can theoretically be thrown by
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// inner_bootstrap() -> g_switch_finish(), but that should
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// never make it back to here. It is a std::exception and
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// would be caught if it is.
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catch (const std::exception& e) {
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std::string base = "greenlet: Unhandled C++ exception: ";
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base += e.what();
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Py_FatalError(base.c_str());
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}
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catch (...) {
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// Some compilers/runtimes use exceptions internally.
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// It appears that GCC on Linux with libstdc++ throws an
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// exception internally at process shutdown time to unwind
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// stacks and clean up resources. Depending on exactly
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// where we are when the process exits, that could result
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// in an unknown exception getting here. If we
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// Py_FatalError() or abort() here, we interfere with
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// orderly process shutdown. Throwing the exception on up
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// is the right thing to do.
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//
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// gevent's ``examples/dns_mass_resolve.py`` demonstrates this.
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#ifndef NDEBUG
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fprintf(stderr,
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"greenlet: inner_bootstrap threw unknown exception; "
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"is the process terminating?\n");
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#endif
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throw;
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}
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Py_FatalError("greenlet: inner_bootstrap returned with no exception.\n");
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}
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// In contrast, notice that we're keeping the origin greenlet
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// around as an owned reference; we need it to call the trace
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// function for the switch back into the parent. It was only
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// captured at the time the switch actually happened, though,
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// so we haven't been keeping an extra reference around this
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// whole time.
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/* back in the parent */
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if (err.status < 0) {
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/* start failed badly, restore greenlet state */
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this->stack_state = StackState();
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this->_main_greenlet.CLEAR();
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// CAUTION: This may run arbitrary Python code.
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run.CLEAR(); // inner_bootstrap didn't run, we own the reference.
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}
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// In the success case, the spawned code (inner_bootstrap) will
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// take care of decrefing this, so we relinquish ownership so as
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|
|
// to not double-decref.
|
||
|
|
|
||
|
|
run.relinquish_ownership();
|
||
|
|
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void
|
||
|
|
UserGreenlet::inner_bootstrap(PyGreenlet* origin_greenlet, PyObject* run)
|
||
|
|
{
|
||
|
|
// The arguments here would be another great place for move.
|
||
|
|
// As it is, we take them as a reference so that when we clear
|
||
|
|
// them we clear what's on the stack above us. Do that NOW, and
|
||
|
|
// without using a C++ RAII object,
|
||
|
|
// so there's no way that exiting the parent frame can clear it,
|
||
|
|
// or we clear it unexpectedly. This arises in the context of the
|
||
|
|
// interpreter shutting down. See https://github.com/python-greenlet/greenlet/issues/325
|
||
|
|
//PyObject* run = _run.relinquish_ownership();
|
||
|
|
|
||
|
|
/* in the new greenlet */
|
||
|
|
assert(this->thread_state()->borrow_current() == this->_self);
|
||
|
|
// C++ exceptions cannot propagate to the parent greenlet from
|
||
|
|
// here. (TODO: Do we need a catch(...) clause, perhaps on the
|
||
|
|
// function itself? ALl we could do is terminate the program.)
|
||
|
|
// NOTE: On 32-bit Windows, the call chain is extremely
|
||
|
|
// important here in ways that are subtle, having to do with
|
||
|
|
// the depth of the SEH list. The call to restore it MUST NOT
|
||
|
|
// add a new SEH handler to the list, or we'll restore it to
|
||
|
|
// the wrong thing.
|
||
|
|
this->thread_state()->restore_exception_state();
|
||
|
|
/* stack variables from above are no good and also will not unwind! */
|
||
|
|
// EXCEPT: That can't be true, we access run, among others, here.
|
||
|
|
|
||
|
|
this->stack_state.set_active(); /* running */
|
||
|
|
|
||
|
|
// We're about to possibly run Python code again, which
|
||
|
|
// could switch back/away to/from us, so we need to grab the
|
||
|
|
// arguments locally.
|
||
|
|
SwitchingArgs args;
|
||
|
|
args <<= this->args();
|
||
|
|
assert(!this->args());
|
||
|
|
|
||
|
|
// XXX: We could clear this much earlier, right?
|
||
|
|
// Or would that introduce the possibility of running Python
|
||
|
|
// code when we don't want to?
|
||
|
|
// CAUTION: This may run arbitrary Python code.
|
||
|
|
this->_run_callable.CLEAR();
|
||
|
|
|
||
|
|
|
||
|
|
// The first switch we need to manually call the trace
|
||
|
|
// function here instead of in g_switch_finish, because we
|
||
|
|
// never return there.
|
||
|
|
if (OwnedObject tracefunc = this->thread_state()->get_tracefunc()) {
|
||
|
|
OwnedGreenlet trace_origin;
|
||
|
|
trace_origin = origin_greenlet;
|
||
|
|
try {
|
||
|
|
g_calltrace(tracefunc,
|
||
|
|
args ? mod_globs->event_switch : mod_globs->event_throw,
|
||
|
|
trace_origin,
|
||
|
|
this->_self);
|
||
|
|
}
|
||
|
|
catch (const PyErrOccurred&) {
|
||
|
|
/* Turn trace errors into switch throws */
|
||
|
|
args.CLEAR();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// We no longer need the origin, it was only here for
|
||
|
|
// tracing.
|
||
|
|
// We may never actually exit this stack frame so we need
|
||
|
|
// to explicitly clear it.
|
||
|
|
// This could run Python code and switch.
|
||
|
|
Py_CLEAR(origin_greenlet);
|
||
|
|
|
||
|
|
OwnedObject result;
|
||
|
|
if (!args) {
|
||
|
|
/* pending exception */
|
||
|
|
result = NULL;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
/* call g.run(*args, **kwargs) */
|
||
|
|
// This could result in further switches
|
||
|
|
try {
|
||
|
|
//result = run.PyCall(args.args(), args.kwargs());
|
||
|
|
// CAUTION: Just invoking this, before the function even
|
||
|
|
// runs, may cause memory allocations, which may trigger
|
||
|
|
// GC, which may run arbitrary Python code.
|
||
|
|
result = OwnedObject::consuming(PyObject_Call(run, args.args().borrow(), args.kwargs().borrow()));
|
||
|
|
}
|
||
|
|
catch (...) {
|
||
|
|
// Unhandled C++ exception!
|
||
|
|
|
||
|
|
// If we declare ourselves as noexcept, if we don't catch
|
||
|
|
// this here, most platforms will just abort() the
|
||
|
|
// process. But on 64-bit Windows with older versions of
|
||
|
|
// the C runtime, this can actually corrupt memory and
|
||
|
|
// just return. We see this when compiling with the
|
||
|
|
// Windows 7.0 SDK targeting Windows Server 2008, but not
|
||
|
|
// when using the Appveyor Visual Studio 2019 image. So
|
||
|
|
// this currently only affects Python 2.7 on Windows 64.
|
||
|
|
// That is, the tests pass and the runtime aborts
|
||
|
|
// everywhere else.
|
||
|
|
//
|
||
|
|
// However, if we catch it and try to continue with a
|
||
|
|
// Python error, then all Windows 64 bit platforms corrupt
|
||
|
|
// memory. So all we can do is manually abort, hopefully
|
||
|
|
// with a good error message. (Note that the above was
|
||
|
|
// tested WITHOUT the `/EHr` switch being used at compile
|
||
|
|
// time, so MSVC may have "optimized" out important
|
||
|
|
// checking. Using that switch, we may be in a better
|
||
|
|
// place in terms of memory corruption.) But sometimes it
|
||
|
|
// can't be caught here at all, which is confusing but not
|
||
|
|
// terribly surprising; so again, the G_NOEXCEPT_WIN32
|
||
|
|
// plus "/EHr".
|
||
|
|
//
|
||
|
|
// Hopefully the basic C stdlib is still functional enough
|
||
|
|
// for us to at least print an error.
|
||
|
|
//
|
||
|
|
// It gets more complicated than that, though, on some
|
||
|
|
// platforms, specifically at least Linux/gcc/libstdc++. They use
|
||
|
|
// an exception to unwind the stack when a background
|
||
|
|
// thread exits. (See comments about noexcept.) So this
|
||
|
|
// may not actually represent anything untoward. On those
|
||
|
|
// platforms we allow throws of this to propagate, or
|
||
|
|
// attempt to anyway.
|
||
|
|
# if defined(WIN32) || defined(_WIN32)
|
||
|
|
Py_FatalError(
|
||
|
|
"greenlet: Unhandled C++ exception from a greenlet run function. "
|
||
|
|
"Because memory is likely corrupted, terminating process.");
|
||
|
|
std::abort();
|
||
|
|
#else
|
||
|
|
throw;
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// These lines may run arbitrary code
|
||
|
|
args.CLEAR();
|
||
|
|
Py_CLEAR(run);
|
||
|
|
|
||
|
|
if (!result
|
||
|
|
&& mod_globs->PyExc_GreenletExit.PyExceptionMatches()
|
||
|
|
&& (this->args())) {
|
||
|
|
// This can happen, for example, if our only reference
|
||
|
|
// goes away after we switch back to the parent.
|
||
|
|
// See test_dealloc_switch_args_not_lost
|
||
|
|
PyErrPieces clear_error;
|
||
|
|
result <<= this->args();
|
||
|
|
result = single_result(result);
|
||
|
|
}
|
||
|
|
this->release_args();
|
||
|
|
this->python_state.did_finish(PyThreadState_GET());
|
||
|
|
|
||
|
|
result = g_handle_exit(result);
|
||
|
|
assert(this->thread_state()->borrow_current() == this->_self);
|
||
|
|
|
||
|
|
/* jump back to parent */
|
||
|
|
this->stack_state.set_inactive(); /* dead */
|
||
|
|
|
||
|
|
|
||
|
|
// TODO: Can we decref some things here? Release our main greenlet
|
||
|
|
// and maybe parent?
|
||
|
|
for (Greenlet* parent = this->_parent;
|
||
|
|
parent;
|
||
|
|
parent = parent->parent()) {
|
||
|
|
// We need to somewhere consume a reference to
|
||
|
|
// the result; in most cases we'll never have control
|
||
|
|
// back in this stack frame again. Calling
|
||
|
|
// green_switch actually adds another reference!
|
||
|
|
// This would probably be clearer with a specific API
|
||
|
|
// to hand results to the parent.
|
||
|
|
parent->args() <<= result;
|
||
|
|
assert(!result);
|
||
|
|
// The parent greenlet now owns the result; in the
|
||
|
|
// typical case we'll never get back here to assign to
|
||
|
|
// result and thus release the reference.
|
||
|
|
try {
|
||
|
|
result = parent->g_switch();
|
||
|
|
}
|
||
|
|
catch (const PyErrOccurred&) {
|
||
|
|
// Ignore, keep passing the error on up.
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Return here means switch to parent failed,
|
||
|
|
* in which case we throw *current* exception
|
||
|
|
* to the next parent in chain.
|
||
|
|
*/
|
||
|
|
assert(!result);
|
||
|
|
}
|
||
|
|
/* We ran out of parents, cannot continue */
|
||
|
|
PyErr_WriteUnraisable(this->self().borrow_o());
|
||
|
|
Py_FatalError("greenlet: ran out of parent greenlets while propagating exception; "
|
||
|
|
"cannot continue");
|
||
|
|
std::abort();
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
UserGreenlet::run(const BorrowedObject nrun)
|
||
|
|
{
|
||
|
|
if (this->started()) {
|
||
|
|
throw AttributeError(
|
||
|
|
"run cannot be set "
|
||
|
|
"after the start of the greenlet");
|
||
|
|
}
|
||
|
|
this->_run_callable = nrun;
|
||
|
|
}
|
||
|
|
|
||
|
|
const OwnedGreenlet
|
||
|
|
UserGreenlet::parent() const
|
||
|
|
{
|
||
|
|
return this->_parent;
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
UserGreenlet::parent(const BorrowedObject raw_new_parent)
|
||
|
|
{
|
||
|
|
if (!raw_new_parent) {
|
||
|
|
throw AttributeError("can't delete attribute");
|
||
|
|
}
|
||
|
|
|
||
|
|
BorrowedMainGreenlet main_greenlet_of_new_parent;
|
||
|
|
BorrowedGreenlet new_parent(raw_new_parent.borrow()); // could
|
||
|
|
// throw
|
||
|
|
// TypeError!
|
||
|
|
for (BorrowedGreenlet p = new_parent; p; p = p->parent()) {
|
||
|
|
if (p == this->_self) {
|
||
|
|
throw ValueError("cyclic parent chain");
|
||
|
|
}
|
||
|
|
main_greenlet_of_new_parent = p->main_greenlet();
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!main_greenlet_of_new_parent) {
|
||
|
|
throw ValueError("parent must not be garbage collected");
|
||
|
|
}
|
||
|
|
|
||
|
|
if (this->started()
|
||
|
|
&& this->_main_greenlet != main_greenlet_of_new_parent) {
|
||
|
|
throw ValueError("parent cannot be on a different thread");
|
||
|
|
}
|
||
|
|
|
||
|
|
this->_parent = new_parent;
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
UserGreenlet::murder_in_place()
|
||
|
|
{
|
||
|
|
this->_main_greenlet.CLEAR();
|
||
|
|
Greenlet::murder_in_place();
|
||
|
|
}
|
||
|
|
|
||
|
|
bool
|
||
|
|
UserGreenlet::belongs_to_thread(const ThreadState* thread_state) const
|
||
|
|
{
|
||
|
|
return Greenlet::belongs_to_thread(thread_state) && this->_main_greenlet == thread_state->borrow_main_greenlet();
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int
|
||
|
|
UserGreenlet::tp_traverse(visitproc visit, void* arg)
|
||
|
|
{
|
||
|
|
Py_VISIT(this->_parent.borrow_o());
|
||
|
|
Py_VISIT(this->_main_greenlet.borrow_o());
|
||
|
|
Py_VISIT(this->_run_callable.borrow_o());
|
||
|
|
|
||
|
|
return Greenlet::tp_traverse(visit, arg);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
UserGreenlet::tp_clear()
|
||
|
|
{
|
||
|
|
Greenlet::tp_clear();
|
||
|
|
this->_parent.CLEAR();
|
||
|
|
this->_main_greenlet.CLEAR();
|
||
|
|
this->_run_callable.CLEAR();
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
UserGreenlet::ParentIsCurrentGuard::ParentIsCurrentGuard(UserGreenlet* p,
|
||
|
|
const ThreadState& thread_state)
|
||
|
|
: oldparent(p->_parent),
|
||
|
|
greenlet(p)
|
||
|
|
{
|
||
|
|
p->_parent = thread_state.get_current();
|
||
|
|
}
|
||
|
|
|
||
|
|
UserGreenlet::ParentIsCurrentGuard::~ParentIsCurrentGuard()
|
||
|
|
{
|
||
|
|
this->greenlet->_parent = oldparent;
|
||
|
|
oldparent.CLEAR();
|
||
|
|
}
|
||
|
|
|
||
|
|
}; //namespace greenlet
|