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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=8 et :
*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include <map>
#include <mach/vm_map.h>
#include <mach/mach_port.h>
#if defined(XP_IOS)
# include <mach/vm_map.h>
# define mach_vm_address_t vm_address_t
# define mach_vm_map vm_map
# define mach_vm_read vm_read
# define mach_vm_region_recurse vm_region_recurse_64
# define mach_vm_size_t vm_size_t
#else
# include <mach/mach_vm.h>
#endif
#include <pthread.h>
#include <unistd.h>
#include "SharedMemoryBasic.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/Printf.h"
#include "mozilla/StaticMutex.h"
#ifdef DEBUG
# define LOG_ERROR(str, args...) \
PR_BEGIN_MACRO \
mozilla::SmprintfPointer msg = mozilla::Smprintf(str, ##args); \
NS_WARNING(msg.get()); \
PR_END_MACRO
#else
# define LOG_ERROR(str, args...) \
do { /* nothing */ \
} while (0)
#endif
namespace mozilla {
namespace ipc {
SharedMemoryBasic::SharedMemoryBasic()
: mPort(MACH_PORT_NULL), mMemory(nullptr), mOpenRights(RightsReadWrite) {}
SharedMemoryBasic::~SharedMemoryBasic() {
Unmap();
CloseHandle();
}
bool SharedMemoryBasic::SetHandle(Handle aHandle, OpenRights aRights) {
MOZ_ASSERT(mPort == MACH_PORT_NULL, "already initialized");
mPort = std::move(aHandle);
mOpenRights = aRights;
return true;
}
static inline void* toPointer(mach_vm_address_t address) {
return reinterpret_cast<void*>(static_cast<uintptr_t>(address));
}
static inline mach_vm_address_t toVMAddress(void* pointer) {
return static_cast<mach_vm_address_t>(reinterpret_cast<uintptr_t>(pointer));
}
bool SharedMemoryBasic::Create(size_t size) {
MOZ_ASSERT(mPort == MACH_PORT_NULL, "already initialized");
memory_object_size_t memoryObjectSize = round_page(size);
kern_return_t kr =
mach_make_memory_entry_64(mach_task_self(), &memoryObjectSize, 0,
MAP_MEM_NAMED_CREATE | VM_PROT_DEFAULT,
getter_Transfers(mPort), MACH_PORT_NULL);
if (kr != KERN_SUCCESS || memoryObjectSize < round_page(size)) {
LOG_ERROR("Failed to make memory entry (%zu bytes). %s (%x)\n", size,
mach_error_string(kr), kr);
CloseHandle();
return false;
}
Created(size);
return true;
}
bool SharedMemoryBasic::Map(size_t size, void* fixed_address) {
MOZ_ASSERT(mMemory == nullptr);
if (MACH_PORT_NULL == mPort) {
return false;
}
kern_return_t kr;
mach_vm_address_t address = toVMAddress(fixed_address);
vm_prot_t vmProtection = VM_PROT_READ;
if (mOpenRights == RightsReadWrite) {
vmProtection |= VM_PROT_WRITE;
}
kr = mach_vm_map(mach_task_self(), &address, round_page(size), 0,
fixed_address ? VM_FLAGS_FIXED : VM_FLAGS_ANYWHERE,
mPort.get(), 0, false, vmProtection, vmProtection,
VM_INHERIT_NONE);
if (kr != KERN_SUCCESS) {
if (!fixed_address) {
LOG_ERROR(
"Failed to map shared memory (%zu bytes) into %x, port %x. %s (%x)\n",
size, mach_task_self(), mach_port_t(mPort.get()),
mach_error_string(kr), kr);
}
return false;
}
if (fixed_address && fixed_address != toPointer(address)) {
kr = vm_deallocate(mach_task_self(), address, size);
if (kr != KERN_SUCCESS) {
LOG_ERROR("Failed to unmap shared memory at unsuitable address "
"(%zu bytes) from %x, port %x. %s (%x)\n",
size, mach_task_self(), mach_port_t(mPort.get()),
mach_error_string(kr), kr);
}
return false;
}
mMemory = toPointer(address);
Mapped(size);
return true;
}
void* SharedMemoryBasic::FindFreeAddressSpace(size_t size) {
mach_vm_address_t address = 0;
size = round_page(size);
if (mach_vm_map(mach_task_self(), &address, size, 0, VM_FLAGS_ANYWHERE,
MEMORY_OBJECT_NULL, 0, false, VM_PROT_NONE, VM_PROT_NONE,
VM_INHERIT_NONE) != KERN_SUCCESS ||
vm_deallocate(mach_task_self(), address, size) != KERN_SUCCESS) {
return nullptr;
}
return toPointer(address);
}
auto SharedMemoryBasic::CloneHandle() -> Handle {
return mozilla::RetainMachSendRight(mPort.get());
}
auto SharedMemoryBasic::TakeHandle() -> Handle {
mOpenRights = RightsReadWrite;
return std::move(mPort);
}
void SharedMemoryBasic::Unmap() {
if (!mMemory) {
return;
}
vm_address_t address = toVMAddress(mMemory);
kern_return_t kr =
vm_deallocate(mach_task_self(), address, round_page(mMappedSize));
if (kr != KERN_SUCCESS) {
LOG_ERROR("Failed to deallocate shared memory. %s (%x)\n",
mach_error_string(kr), kr);
return;
}
mMemory = nullptr;
}
bool SharedMemoryBasic::IsHandleValid(const Handle& aHandle) const {
return aHandle != nullptr;
}
} // namespace ipc
} // namespace mozilla