src/base/mach_ipc_mac.mm - cobalt - Git at Google

 // Copyright (c) 2012 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 <mach/vm_map.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 mac {

 kern_return_t GetNumberOfMachPorts(mach_port_t task_port, int* num_ports) {
   mach_port_name_array_t names;
   mach_msg_type_number_t names_count;
   mach_port_type_array_t types;
   mach_msg_type_number_t types_count;

   // A friendlier interface would allow NULL buffers to only get the counts.
   kern_return_t kr = mach_port_names(task_port, &names, &names_count,
                                      &types, &types_count);
   if (kr != KERN_SUCCESS)
     return kr;

   // The documentation states this is an invariant.
   DCHECK_EQ(names_count, types_count);
   *num_ports = names_count;

   kr = vm_deallocate(mach_task_self(),
       reinterpret_cast<vm_address_t>(names),
       names_count * sizeof(mach_port_name_array_t));
   kr = vm_deallocate(mach_task_self(),
       reinterpret_cast<vm_address_t>(types),
       types_count * sizeof(mach_port_type_array_t));

   return kr;
 }

 }  // namespace mac

 }  // namespace base
	// Copyright (c) 2012 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 <mach/vm_map.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 mac {

	kern_return_t GetNumberOfMachPorts(mach_port_t task_port, int* num_ports) {
	mach_port_name_array_t names;
	mach_msg_type_number_t names_count;
	mach_port_type_array_t types;
	mach_msg_type_number_t types_count;

	// A friendlier interface would allow NULL buffers to only get the counts.
	kern_return_t kr = mach_port_names(task_port, &names, &names_count,
	&types, &types_count);
	if (kr != KERN_SUCCESS)
	return kr;

	// The documentation states this is an invariant.
	DCHECK_EQ(names_count, types_count);
	*num_ports = names_count;

	kr = vm_deallocate(mach_task_self(),
	reinterpret_cast<vm_address_t>(names),
	names_count * sizeof(mach_port_name_array_t));
	kr = vm_deallocate(mach_task_self(),
	reinterpret_cast<vm_address_t>(types),
	types_count * sizeof(mach_port_type_array_t));

	return kr;
	}

	} // namespace mac

	} // namespace base