diff options
| -rw-r--r-- | src/libexpr/eval.cc | 20 | ||||
| -rw-r--r-- | src/libutil/serialise.cc | 38 | ||||
| -rw-r--r-- | src/libutil/serialise.hh | 10 |
3 files changed, 34 insertions, 34 deletions
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index a5a198926..01680afff 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -325,20 +325,22 @@ static Symbol getName(const AttrName & name, EvalState & state, Env & env) } } - -class BoehmDisableGC : public DisableGC { +#if HAVE_BOEHMGC +/* Disable GC while this object lives. Used by CoroutineContext. + * + * Boehm keeps a count of GC_disable() and GC_enable() calls, + * and only enables GC when the count matches. + */ +class BoehmDisableGC { public: BoehmDisableGC() { -#if HAVE_BOEHMGC GC_disable(); -#endif }; - virtual ~BoehmDisableGC() override { -#if HAVE_BOEHMGC + ~BoehmDisableGC() { GC_enable(); -#endif }; }; +#endif static bool gcInitialised = false; @@ -365,8 +367,8 @@ void initGC() /* Used to disable GC when entering coroutines on macOS */ - DisableGC::create = []() { - return std::dynamic_pointer_cast<DisableGC>(std::make_shared<BoehmDisableGC>()); + create_disable_gc = []() -> std::shared_ptr<void> { + return std::make_shared<BoehmDisableGC>(); }; /* Set the initial heap size to something fairly big (25% of diff --git a/src/libutil/serialise.cc b/src/libutil/serialise.cc index 531100c01..7ef24d458 100644 --- a/src/libutil/serialise.cc +++ b/src/libutil/serialise.cc @@ -186,8 +186,21 @@ static DefaultStackAllocator defaultAllocatorSingleton; StackAllocator *StackAllocator::defaultAllocator = &defaultAllocatorSingleton; -std::shared_ptr<DisableGC> (*DisableGC::create)() = []() { - return std::dynamic_pointer_cast<DisableGC>(std::make_shared<DisableGC>()); +std::shared_ptr<void> (*create_disable_gc)() = []() -> std::shared_ptr<void> { + return {}; +}; + +/* This class is used for entry and exit hooks on coroutines */ +class CoroutineContext { +#if __APPLE__ + /* Disable GC when entering the coroutine on macOS, since it doesn't find the main thread stack in this case. + * std::shared_ptr<void> performs type-erasure, so it will call the right + * deleter. */ + const std::shared_ptr<void> disable_gc = create_disable_gc(); +#endif +public: + CoroutineContext() {}; + ~CoroutineContext() {}; }; std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun) @@ -211,10 +224,7 @@ std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun) cur = in; if (!coro) { -#if __APPLE__ - /* Disable GC when entering the coroutine on macOS, since it doesn't find the main thread stack in this case */ - auto disablegc = DisableGC::create(); -#endif + CoroutineContext ctx; coro = coro_t::push_type(VirtualStackAllocator{}, [&](coro_t::pull_type & yield) { LambdaSource source([&](char *out, size_t out_len) { if (cur.empty()) { @@ -236,9 +246,7 @@ std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun) if (!*coro) { abort(); } if (!cur.empty()) { -#if __APPLE__ - auto disablegc = DisableGC::create(); -#endif + CoroutineContext ctx; (*coro)(false); } } @@ -248,9 +256,7 @@ std::unique_ptr<FinishSink> sourceToSink(std::function<void(Source &)> fun) if (!coro) return; if (!*coro) abort(); { -#if __APPLE__ - auto disablegc = DisableGC::create(); -#endif + CoroutineContext ctx; (*coro)(true); } if (*coro) abort(); @@ -284,9 +290,7 @@ std::unique_ptr<Source> sinkToSource( size_t read(char * data, size_t len) override { if (!coro) { -#if __APPLE__ - auto disablegc = DisableGC::create(); -#endif + CoroutineContext ctx; coro = coro_t::pull_type(VirtualStackAllocator{}, [&](coro_t::push_type & yield) { LambdaSink sink([&](std::string_view data) { if (!data.empty()) yield(std::string(data)); @@ -299,9 +303,7 @@ std::unique_ptr<Source> sinkToSource( if (pos == cur.size()) { if (!cur.empty()) { -#if __APPLE__ - auto disablegc = DisableGC::create(); -#endif + CoroutineContext ctx; (*coro)(); } cur = coro->get(); diff --git a/src/libutil/serialise.hh b/src/libutil/serialise.hh index fb1f14a3b..58b9499db 100644 --- a/src/libutil/serialise.hh +++ b/src/libutil/serialise.hh @@ -502,13 +502,9 @@ struct StackAllocator { }; /* Disabling GC when entering a coroutine (on macos). - ::create is to avoid boehm gc dependency in libutil. + mutable to avoid boehm gc dependency in libutil. */ -class DisableGC { -public: - DisableGC() {}; - virtual ~DisableGC() {}; - static std::shared_ptr<DisableGC> (*create)(); -}; +extern std::shared_ptr<void> (*create_disable_gc)(); + } |