From 7e10bb1469ff394994402c6cbbf5617a30cbc4c2 Mon Sep 17 00:00:00 2001
From: avdgrinten <alexander.vandergrinten@gmail.com>
Date: Sat, 5 Dec 2015 19:00:01 +0100
Subject: [PATCH] Implement __cxa_atexit()

---
 libc/generic/lsb/dir.makefile                 |  4 +++
 libc/generic/lsb/src/dso_exit.cpp             | 33 +++++++++++++++++--
 .../include/mlibc/frigg-alloc.hpp             | 25 ++++++++++++++
 libc/platform/x86_64-managarm/src/entry.cpp   |  4 +++
 libc/platform/x86_64-managarm/src/malloc.cpp  | 21 +++++-------
 5 files changed, 72 insertions(+), 15 deletions(-)
 create mode 100644 libc/platform/x86_64-managarm/include/mlibc/frigg-alloc.hpp

diff --git a/libc/generic/lsb/dir.makefile b/libc/generic/lsb/dir.makefile
index 9ba18bb3..0125f4d8 100644
--- a/libc/generic/lsb/dir.makefile
+++ b/libc/generic/lsb/dir.makefile
@@ -10,10 +10,14 @@ $c_OBJECT_PATHS := $(addprefix $($c_OBJDIR)/,$($c_OBJECTS))
 
 $c_CXX := x86_64-managarm-g++
 $c_CPPFLAGS := -std=c++11 -Wall
+$c_CPPFLAGS += -I$(FRIGG_PATH)/include
 $c_CPPFLAGS += -I$(TREE_PATH)/libc/generic/ansi/include
 $c_CPPFLAGS += -I$(TREE_PATH)/libc/generic/posix/include
 $c_CPPFLAGS += -I$(TREE_PATH)/libc/compilers/gcc/include
+$c_CPPFLAGS += -I$(TREE_PATH)/libc/platform/x86_64-managarm/include
+$c_CPPFLAGS += -DFRIGG_HAVE_LIBC
 $c_CXXFLAGS :=  $($c_CPPFLAGS) -fPIC -O2
+$c_CXXFLAGS +=  -fno-rtti -fno-exceptions
 
 $c_TARGETS := clean-$c install-$c $($c_OBJECT_PATHS)
 
diff --git a/libc/generic/lsb/src/dso_exit.cpp b/libc/generic/lsb/src/dso_exit.cpp
index c51bca18..d76d9259 100644
--- a/libc/generic/lsb/src/dso_exit.cpp
+++ b/libc/generic/lsb/src/dso_exit.cpp
@@ -1,8 +1,35 @@
 
 #include <mlibc/ensure.h>
 
-extern "C" int __cxa_atexit(void (*handler)(void *), void *argument, void *dso) {
-	__ensure(!"Not implemented");
-	__builtin_unreachable();
+#pragma GCC visibility push(hidden)
+
+#include <mlibc/cxx-support.hpp>
+#include <mlibc/frigg-alloc.hpp>
+
+#include <frigg/initializer.hpp>
+#include <frigg/vector.hpp>
+
+struct ExitHandler {
+	void (*function)(void *);
+	void *argument;
+	void *dsoTag;
+};
+
+frigg::LazyInitializer<frigg::Vector<ExitHandler, MemoryAllocator>> exitHandlers;
+
+#pragma GCC visibility pop
+
+extern "C" int __cxa_atexit(void (*function)(void *), void *argument, void *dso_tag) {
+	// FIXME: initialize this from a global library guard constructor
+	__ensure(memoryAllocator);
+	if(!exitHandlers)
+		exitHandlers.initialize(*memoryAllocator);
+
+	ExitHandler handler;
+	handler.function = function;
+	handler.argument = argument;
+	handler.dsoTag = dso_tag;
+	exitHandlers->push(handler);
+	return 0;
 }
 
diff --git a/libc/platform/x86_64-managarm/include/mlibc/frigg-alloc.hpp b/libc/platform/x86_64-managarm/include/mlibc/frigg-alloc.hpp
new file mode 100644
index 00000000..7ef4b027
--- /dev/null
+++ b/libc/platform/x86_64-managarm/include/mlibc/frigg-alloc.hpp
@@ -0,0 +1,25 @@
+
+#ifndef MLIBC_FRIGG_ALLOC
+#define MLIBC_FRIGG_ALLOC
+
+#pragma GCC visibility push(hidden)
+
+#include <frigg/initializer.hpp>
+#include <frigg/memory.hpp>
+
+struct VirtualAllocator {
+public:
+	uintptr_t map(size_t length);
+
+	void unmap(uintptr_t address, size_t length);
+};
+
+typedef frigg::SlabAllocator<VirtualAllocator, frigg::TicketLock> MemoryAllocator;
+
+extern VirtualAllocator virtualAllocator;
+extern frigg::LazyInitializer<MemoryAllocator> memoryAllocator;
+
+#pragma GCC visibility pop
+
+#endif // MLIBC_FRIGG_ALLOC
+
diff --git a/libc/platform/x86_64-managarm/src/entry.cpp b/libc/platform/x86_64-managarm/src/entry.cpp
index a7a8789d..30a6a00c 100644
--- a/libc/platform/x86_64-managarm/src/entry.cpp
+++ b/libc/platform/x86_64-managarm/src/entry.cpp
@@ -16,6 +16,10 @@ LibraryGuard::LibraryGuard() {
 	//__mlibc_initMalloc();
 }
 
+// __dso_handle is usually defined in crtbeginS.o
+// Since we link with -nostdlib we have to manually define it here
+__attribute__ (( visibility("hidden") )) int __dso_handle;
+
 extern "C" int main(int argc, char *argv[], char *env[]);
 
 extern "C" void __mlibc_entry() {
diff --git a/libc/platform/x86_64-managarm/src/malloc.cpp b/libc/platform/x86_64-managarm/src/malloc.cpp
index 93959a0e..11615c3e 100644
--- a/libc/platform/x86_64-managarm/src/malloc.cpp
+++ b/libc/platform/x86_64-managarm/src/malloc.cpp
@@ -4,23 +4,23 @@
 
 #include <mlibc/ensure.h>
 #include <mlibc/cxx-support.hpp>
+#include <mlibc/frigg-alloc.hpp>
 
 #pragma GCC visibility push(hidden)
 
-#include <frigg/initializer.hpp>
-#include <frigg/memory.hpp>
-
 #include <hel.h>
 #include <hel-syscalls.h>
 
-struct VirtualAllocator {
-public:
-	uintptr_t map(size_t length);
+// --------------------------------------------------------
+// Globals
+// --------------------------------------------------------
 
-	void unmap(uintptr_t address, size_t length);
-};
+VirtualAllocator virtualAllocator;
+frigg::LazyInitializer<MemoryAllocator> memoryAllocator;
 
-typedef frigg::SlabAllocator<VirtualAllocator, frigg::TicketLock> MemoryAllocator;
+// --------------------------------------------------------
+// VirtualAllocator
+// --------------------------------------------------------
 
 uintptr_t VirtualAllocator::map(size_t length) {
 	assert((length % 0x1000) == 0);
@@ -38,9 +38,6 @@ void VirtualAllocator::unmap(uintptr_t address, size_t length) {
 	HEL_CHECK(helUnmapMemory(kHelNullHandle, (void *)address, length));
 }
 
-VirtualAllocator virtualAllocator;
-frigg::LazyInitializer<MemoryAllocator> memoryAllocator;
-
 #pragma GCC visibility pop
 
 void __mlibc_initMalloc() {