blob: b6dedd2b89190b7cea5dba167105c77db155e818 [file] [log] [blame]
// Copyright (c) 2011 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/mach_ipc_mac.h"
#import <Foundation/Foundation.h>
#include <stdio.h>
#include "base/logging.h"
namespace base {
// static
const size_t MachMessage::kEmptyMessageSize = sizeof(mach_msg_header_t) +
sizeof(mach_msg_body_t) + sizeof(MessageDataPacket);
//==============================================================================
MachSendMessage::MachSendMessage(int32_t message_id) : MachMessage() {
Initialize(message_id);
}
MachSendMessage::MachSendMessage(void *storage, size_t storage_length,
int32_t message_id)
: MachMessage(storage, storage_length) {
Initialize(message_id);
}
void MachSendMessage::Initialize(int32_t message_id) {
Head()->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0);
// head.msgh_remote_port = ...; // filled out in MachPortSender::SendMessage()
Head()->msgh_local_port = MACH_PORT_NULL;
Head()->msgh_reserved = 0;
Head()->msgh_id = 0;
SetDescriptorCount(0); // start out with no descriptors
SetMessageID(message_id);
SetData(NULL, 0); // client may add data later
}
//==============================================================================
MachMessage::MachMessage()
: storage_(new MachMessageData), // Allocate storage_ ourselves
storage_length_bytes_(sizeof(MachMessageData)),
own_storage_(true) {
memset(storage_, 0, storage_length_bytes_);
}
//==============================================================================
MachMessage::MachMessage(void *storage, size_t storage_length)
: storage_(static_cast<MachMessageData*>(storage)),
storage_length_bytes_(storage_length),
own_storage_(false) {
DCHECK(storage);
DCHECK_GE(storage_length, kEmptyMessageSize);
}
//==============================================================================
MachMessage::~MachMessage() {
if (own_storage_) {
delete storage_;
storage_ = NULL;
}
}
//==============================================================================
// returns true if successful
bool MachMessage::SetData(const void* data,
int32_t data_length) {
// Enforce the fact that it's only safe to call this method once on a
// message.
DCHECK(GetDataPacket()->data_length == 0);
// first check to make sure we have enough space
int size = CalculateSize();
int new_size = size + data_length;
if ((unsigned)new_size > storage_length_bytes_) {
return false; // not enough space
}
GetDataPacket()->data_length = EndianU32_NtoL(data_length);
if (data) memcpy(GetDataPacket()->data, data, data_length);
// Update the Mach header with the new aligned size of the message.
CalculateSize();
return true;
}
//==============================================================================
// calculates and returns the total size of the message
// Currently, the entire message MUST fit inside of the MachMessage
// messsage size <= EmptyMessageSize()
int MachMessage::CalculateSize() {
int size = sizeof(mach_msg_header_t) + sizeof(mach_msg_body_t);
// add space for MessageDataPacket
int32_t alignedDataLength = (GetDataLength() + 3) & ~0x3;
size += 2*sizeof(int32_t) + alignedDataLength;
// add space for descriptors
size += GetDescriptorCount() * sizeof(MachMsgPortDescriptor);
Head()->msgh_size = size;
return size;
}
//==============================================================================
MachMessage::MessageDataPacket *MachMessage::GetDataPacket() {
int desc_size = sizeof(MachMsgPortDescriptor)*GetDescriptorCount();
MessageDataPacket *packet =
reinterpret_cast<MessageDataPacket*>(storage_->padding + desc_size);
return packet;
}
//==============================================================================
void MachMessage::SetDescriptor(int n,
const MachMsgPortDescriptor &desc) {
MachMsgPortDescriptor *desc_array =
reinterpret_cast<MachMsgPortDescriptor*>(storage_->padding);
desc_array[n] = desc;
}
//==============================================================================
// returns true if successful otherwise there was not enough space
bool MachMessage::AddDescriptor(const MachMsgPortDescriptor &desc) {
// first check to make sure we have enough space
int size = CalculateSize();
int new_size = size + sizeof(MachMsgPortDescriptor);
if ((unsigned)new_size > storage_length_bytes_) {
return false; // not enough space
}
// unfortunately, we need to move the data to allow space for the
// new descriptor
u_int8_t *p = reinterpret_cast<u_int8_t*>(GetDataPacket());
bcopy(p, p+sizeof(MachMsgPortDescriptor), GetDataLength()+2*sizeof(int32_t));
SetDescriptor(GetDescriptorCount(), desc);
SetDescriptorCount(GetDescriptorCount() + 1);
CalculateSize();
return true;
}
//==============================================================================
void MachMessage::SetDescriptorCount(int n) {
storage_->body.msgh_descriptor_count = n;
if (n > 0) {
Head()->msgh_bits |= MACH_MSGH_BITS_COMPLEX;
} else {
Head()->msgh_bits &= ~MACH_MSGH_BITS_COMPLEX;
}
}
//==============================================================================
MachMsgPortDescriptor *MachMessage::GetDescriptor(int n) {
if (n < GetDescriptorCount()) {
MachMsgPortDescriptor *desc =
reinterpret_cast<MachMsgPortDescriptor*>(storage_->padding);
return desc + n;
}
return nil;
}
//==============================================================================
mach_port_t MachMessage::GetTranslatedPort(int n) {
if (n < GetDescriptorCount()) {
return GetDescriptor(n)->GetMachPort();
}
return MACH_PORT_NULL;
}
#pragma mark -
//==============================================================================
// create a new mach port for receiving messages and register a name for it
ReceivePort::ReceivePort(const char *receive_port_name) {
mach_port_t current_task = mach_task_self();
init_result_ = mach_port_allocate(current_task,
MACH_PORT_RIGHT_RECEIVE,
&port_);
if (init_result_ != KERN_SUCCESS)
return;
init_result_ = mach_port_insert_right(current_task,
port_,
port_,
MACH_MSG_TYPE_MAKE_SEND);
if (init_result_ != KERN_SUCCESS)
return;
// Without |NSMachPortDeallocateNone|, the NSMachPort seems to deallocate
// receive rights on port when it is eventually released. It is not necessary
// to deallocate any rights here as |port_| is fully deallocated in the
// ReceivePort destructor.
NSPort *ns_port = [NSMachPort portWithMachPort:port_
options:NSMachPortDeallocateNone];
NSString *port_name = [NSString stringWithUTF8String:receive_port_name];
[[NSMachBootstrapServer sharedInstance] registerPort:ns_port name:port_name];
}
//==============================================================================
// create a new mach port for receiving messages
ReceivePort::ReceivePort() {
mach_port_t current_task = mach_task_self();
init_result_ = mach_port_allocate(current_task,
MACH_PORT_RIGHT_RECEIVE,
&port_);
if (init_result_ != KERN_SUCCESS)
return;
init_result_ = mach_port_insert_right(current_task,
port_,
port_,
MACH_MSG_TYPE_MAKE_SEND);
}
//==============================================================================
// Given an already existing mach port, use it. We take ownership of the
// port and deallocate it in our destructor.
ReceivePort::ReceivePort(mach_port_t receive_port)
: port_(receive_port),
init_result_(KERN_SUCCESS) {
}
//==============================================================================
ReceivePort::~ReceivePort() {
if (init_result_ == KERN_SUCCESS)
mach_port_deallocate(mach_task_self(), port_);
}
//==============================================================================
kern_return_t ReceivePort::WaitForMessage(MachReceiveMessage *out_message,
mach_msg_timeout_t timeout) {
if (!out_message) {
return KERN_INVALID_ARGUMENT;
}
// return any error condition encountered in constructor
if (init_result_ != KERN_SUCCESS)
return init_result_;
out_message->Head()->msgh_bits = 0;
out_message->Head()->msgh_local_port = port_;
out_message->Head()->msgh_remote_port = MACH_PORT_NULL;
out_message->Head()->msgh_reserved = 0;
out_message->Head()->msgh_id = 0;
mach_msg_option_t rcv_options = MACH_RCV_MSG;
if (timeout != MACH_MSG_TIMEOUT_NONE)
rcv_options |= MACH_RCV_TIMEOUT;
kern_return_t result = mach_msg(out_message->Head(),
rcv_options,
0,
out_message->MaxSize(),
port_,
timeout, // timeout in ms
MACH_PORT_NULL);
return result;
}
#pragma mark -
//==============================================================================
// get a port with send rights corresponding to a named registered service
MachPortSender::MachPortSender(const char *receive_port_name) {
mach_port_t bootstrap_port = 0;
init_result_ = task_get_bootstrap_port(mach_task_self(), &bootstrap_port);
if (init_result_ != KERN_SUCCESS)
return;
init_result_ = bootstrap_look_up(bootstrap_port,
const_cast<char*>(receive_port_name),
&send_port_);
}
//==============================================================================
MachPortSender::MachPortSender(mach_port_t send_port)
: send_port_(send_port),
init_result_(KERN_SUCCESS) {
}
//==============================================================================
kern_return_t MachPortSender::SendMessage(MachSendMessage &message,
mach_msg_timeout_t timeout) {
if (message.Head()->msgh_size == 0) {
NOTREACHED();
return KERN_INVALID_VALUE; // just for safety -- never should occur
};
if (init_result_ != KERN_SUCCESS)
return init_result_;
message.Head()->msgh_remote_port = send_port_;
kern_return_t result = mach_msg(message.Head(),
MACH_SEND_MSG | MACH_SEND_TIMEOUT,
message.Head()->msgh_size,
0,
MACH_PORT_NULL,
timeout, // timeout in ms
MACH_PORT_NULL);
return result;
}
} // namespace base