AlkantarClanX12
Current Path : /opt/hc_python/lib64/python3.8/site-packages/greenlet/ |
Current File : //opt/hc_python/lib64/python3.8/site-packages/greenlet/TGreenletGlobals.cpp |
/* -*- indent-tabs-mode: nil; tab-width: 4; -*- */ /** * Implementation of GreenletGlobals. * * Format with: * clang-format -i --style=file src/greenlet/greenlet.c * * * Fix missing braces with: * clang-tidy src/greenlet/greenlet.c -fix -checks="readability-braces-around-statements" */ #ifndef T_GREENLET_GLOBALS #define T_GREENLET_GLOBALS #include "greenlet_refs.hpp" #include "greenlet_exceptions.hpp" #include "greenlet_thread_support.hpp" #include "greenlet_internal.hpp" namespace greenlet { // This encapsulates what were previously module global "constants" // established at init time. // This is a step towards Python3 style module state that allows // reloading. // // In an earlier iteration of this code, we used placement new to be // able to allocate this object statically still, so that references // to its members don't incur an extra pointer indirection. // But under some scenarios, that could result in crashes at // shutdown because apparently the destructor was getting run twice? class GreenletGlobals { public: const greenlet::refs::ImmortalEventName event_switch; const greenlet::refs::ImmortalEventName event_throw; const greenlet::refs::ImmortalException PyExc_GreenletError; const greenlet::refs::ImmortalException PyExc_GreenletExit; const greenlet::refs::ImmortalObject empty_tuple; const greenlet::refs::ImmortalObject empty_dict; const greenlet::refs::ImmortalString str_run; Mutex* const thread_states_to_destroy_lock; greenlet::cleanup_queue_t thread_states_to_destroy; GreenletGlobals() : event_switch("switch"), event_throw("throw"), PyExc_GreenletError("greenlet.error"), PyExc_GreenletExit("greenlet.GreenletExit", PyExc_BaseException), empty_tuple(Require(PyTuple_New(0))), empty_dict(Require(PyDict_New())), str_run("run"), thread_states_to_destroy_lock(new Mutex()) {} ~GreenletGlobals() { // This object is (currently) effectively immortal, and not // just because of those placement new tricks; if we try to // deallocate the static object we allocated, and overwrote, // we would be doing so at C++ teardown time, which is after // the final Python GIL is released, and we can't use the API // then. // (The members will still be destructed, but they also don't // do any deallocation.) } void queue_to_destroy(ThreadState* ts) const { // we're currently accessed through a static const object, // implicitly marking our members as const, so code can't just // call push_back (or pop_back) without casting away the // const. // // Do that for callers. greenlet::cleanup_queue_t& q = const_cast<greenlet::cleanup_queue_t&>(this->thread_states_to_destroy); q.push_back(ts); } ThreadState* take_next_to_destroy() const { greenlet::cleanup_queue_t& q = const_cast<greenlet::cleanup_queue_t&>(this->thread_states_to_destroy); ThreadState* result = q.back(); q.pop_back(); return result; } }; }; // namespace greenlet static const greenlet::GreenletGlobals* mod_globs; #endif // T_GREENLET_GLOBALS