| // 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 "base/mac/mac_util.h" |
| #include "base/mac/mach_logging.h" |
| #include "base/unguessable_token.h" |
| |
| namespace base { |
| |
| SharedMemoryHandle::SharedMemoryHandle() {} |
| |
| SharedMemoryHandle::SharedMemoryHandle(mach_vm_size_t size, |
| const base::UnguessableToken& guid) { |
| 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; |
| ownership_passes_to_ipc_ = false; |
| guid_ = guid; |
| } |
| |
| SharedMemoryHandle::SharedMemoryHandle(mach_port_t memory_object, |
| mach_vm_size_t size, |
| const base::UnguessableToken& guid) |
| : memory_object_(memory_object), |
| ownership_passes_to_ipc_(false), |
| guid_(guid), |
| size_(size) {} |
| |
| SharedMemoryHandle SharedMemoryHandle::Duplicate() const { |
| if (!IsValid()) |
| return SharedMemoryHandle(); |
| |
| // 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::IsValid() const { |
| return memory_object_ != MACH_PORT_NULL; |
| } |
| |
| mach_port_t SharedMemoryHandle::GetMemoryObject() const { |
| return memory_object_; |
| } |
| |
| bool SharedMemoryHandle::MapAt(off_t offset, |
| size_t bytes, |
| void** memory, |
| bool read_only) { |
| DCHECK(IsValid()); |
| 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_); |
| MACH_DLOG_IF(ERROR, kr != KERN_SUCCESS, kr) << "Error deallocating mach port"; |
| } |
| |
| void SharedMemoryHandle::SetOwnershipPassesToIPC(bool ownership_passes) { |
| ownership_passes_to_ipc_ = ownership_passes; |
| } |
| |
| bool SharedMemoryHandle::OwnershipPassesToIPC() const { |
| return ownership_passes_to_ipc_; |
| } |
| |
| } // namespace base |