| // Copyright 2015 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "base/memory/shared_memory_handle.h" |
| |
| #include <mach/mach_vm.h> |
| #include <stddef.h> |
| #include <sys/mman.h> |
| #include <unistd.h> |
| |
| #include "base/mac/mac_util.h" |
| #include "base/posix/eintr_wrapper.h" |
| |
| namespace base { |
| |
| SharedMemoryHandle::SharedMemoryHandle() {} |
| |
| SharedMemoryHandle::SharedMemoryHandle(mach_vm_size_t size) { |
| mach_port_t named_right; |
| kern_return_t kr = mach_make_memory_entry_64( |
| mach_task_self(), |
| &size, |
| 0, // Address. |
| MAP_MEM_NAMED_CREATE | VM_PROT_READ | VM_PROT_WRITE, |
| &named_right, |
| MACH_PORT_NULL); // Parent handle. |
| if (kr != KERN_SUCCESS) { |
| memory_object_ = MACH_PORT_NULL; |
| return; |
| } |
| |
| memory_object_ = named_right; |
| size_ = size; |
| pid_ = GetCurrentProcId(); |
| ownership_passes_to_ipc_ = false; |
| } |
| |
| SharedMemoryHandle::SharedMemoryHandle(mach_port_t memory_object, |
| mach_vm_size_t size, |
| base::ProcessId pid) |
| : memory_object_(memory_object), |
| size_(size), |
| pid_(pid), |
| ownership_passes_to_ipc_(false) {} |
| |
| SharedMemoryHandle::SharedMemoryHandle(const SharedMemoryHandle& handle) { |
| CopyRelevantData(handle); |
| } |
| |
| SharedMemoryHandle& SharedMemoryHandle::operator=( |
| const SharedMemoryHandle& handle) { |
| if (this == &handle) |
| return *this; |
| |
| CopyRelevantData(handle); |
| return *this; |
| } |
| |
| SharedMemoryHandle SharedMemoryHandle::Duplicate() const { |
| if (!IsValid()) |
| return SharedMemoryHandle(MACH_PORT_NULL, 0, 0); |
| |
| // Increment the ref count. |
| kern_return_t kr = mach_port_mod_refs(mach_task_self(), memory_object_, |
| MACH_PORT_RIGHT_SEND, 1); |
| DCHECK_EQ(kr, KERN_SUCCESS); |
| SharedMemoryHandle handle(*this); |
| handle.SetOwnershipPassesToIPC(true); |
| return handle; |
| } |
| |
| bool SharedMemoryHandle::operator==(const SharedMemoryHandle& handle) const { |
| if (!IsValid() && !handle.IsValid()) |
| return true; |
| |
| return memory_object_ == handle.memory_object_ && size_ == handle.size_ && |
| pid_ == handle.pid_; |
| } |
| |
| bool SharedMemoryHandle::operator!=(const SharedMemoryHandle& handle) const { |
| return !(*this == handle); |
| } |
| |
| bool SharedMemoryHandle::IsValid() const { |
| return memory_object_ != MACH_PORT_NULL; |
| } |
| |
| mach_port_t SharedMemoryHandle::GetMemoryObject() const { |
| return memory_object_; |
| } |
| |
| bool SharedMemoryHandle::GetSize(size_t* size) const { |
| if (!IsValid()) { |
| *size = 0; |
| return true; |
| } |
| |
| *size = size_; |
| return true; |
| } |
| |
| bool SharedMemoryHandle::MapAt(off_t offset, |
| size_t bytes, |
| void** memory, |
| bool read_only) { |
| DCHECK(IsValid()); |
| DCHECK_EQ(pid_, GetCurrentProcId()); |
| kern_return_t kr = mach_vm_map( |
| mach_task_self(), |
| reinterpret_cast<mach_vm_address_t*>(memory), // Output parameter |
| bytes, |
| 0, // Alignment mask |
| VM_FLAGS_ANYWHERE, memory_object_, offset, |
| FALSE, // Copy |
| VM_PROT_READ | (read_only ? 0 : VM_PROT_WRITE), // Current protection |
| VM_PROT_WRITE | VM_PROT_READ | VM_PROT_IS_MASK, // Maximum protection |
| VM_INHERIT_NONE); |
| return kr == KERN_SUCCESS; |
| } |
| |
| void SharedMemoryHandle::Close() const { |
| if (!IsValid()) |
| return; |
| |
| kern_return_t kr = mach_port_deallocate(mach_task_self(), memory_object_); |
| if (kr != KERN_SUCCESS) |
| DPLOG(ERROR) << "Error deallocating mach port: " << kr; |
| } |
| |
| void SharedMemoryHandle::SetOwnershipPassesToIPC(bool ownership_passes) { |
| ownership_passes_to_ipc_ = ownership_passes; |
| } |
| |
| bool SharedMemoryHandle::OwnershipPassesToIPC() const { |
| return ownership_passes_to_ipc_; |
| } |
| |
| void SharedMemoryHandle::CopyRelevantData(const SharedMemoryHandle& handle) { |
| memory_object_ = handle.memory_object_; |
| size_ = handle.size_; |
| pid_ = handle.pid_; |
| ownership_passes_to_ipc_ = handle.ownership_passes_to_ipc_; |
| } |
| |
| } // namespace base |