LibCore: Add a rough abstraction class around Mach port rights

This commit is contained in:
Andrew Kaster 2024-04-04 13:59:44 -06:00 committed by Andrew Kaster
parent 4a9546a7c8
commit 77f18cf062
Notes: sideshowbarker 2024-07-17 06:29:49 +09:00
4 changed files with 255 additions and 0 deletions

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@ -116,6 +116,9 @@ source_set("sources") {
"LocalServer.h", "LocalServer.h",
] ]
} }
if (current_os == "mac") {
sources += [ "MachPort.cpp" ]
}
} }
source_set("filewatcher") { source_set("filewatcher") {

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@ -69,6 +69,10 @@ else()
list(APPEND SOURCES FileWatcherUnimplemented.cpp) list(APPEND SOURCES FileWatcherUnimplemented.cpp)
endif() endif()
if (APPLE OR CMAKE_SYSTEM_NAME STREQUAL "GNU")
list(APPEND SOURCES MachPort.cpp)
endif()
serenity_lib(LibCore core) serenity_lib(LibCore core)
target_link_libraries(LibCore PRIVATE LibCrypt LibSystem LibTimeZone LibURL) target_link_libraries(LibCore PRIVATE LibCrypt LibSystem LibTimeZone LibURL)
target_link_libraries(LibCore PUBLIC LibCoreMinimal) target_link_libraries(LibCore PUBLIC LibCoreMinimal)

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@ -0,0 +1,166 @@
/*
* Copyright (c) 2024, Andrew Kaster <akaster@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/ByteString.h>
#include <AK/Format.h>
#include <LibCore/MachPort.h>
#if defined(AK_OS_MACOS)
# include <bootstrap.h>
#endif
namespace Core {
static constexpr MachPort::PortRight associated_port_right(MachPort::MessageRight right)
{
switch (right) {
case MachPort::MessageRight::MoveReceive:
case MachPort::MessageRight::CopyReceive:
case MachPort::MessageRight::DisposeReceive:
return MachPort::PortRight::Receive;
case MachPort::MessageRight::MoveSend:
case MachPort::MessageRight::CopySend:
case MachPort::MessageRight::MakeSend:
case MachPort::MessageRight::DisposeSend:
return MachPort::PortRight::Send;
case MachPort::MessageRight::MoveSendOnce:
case MachPort::MessageRight::MakeSendOnce:
case MachPort::MessageRight::DisposeSendOnce:
return MachPort::PortRight::SendOnce;
}
VERIFY_NOT_REACHED();
}
Error mach_error_to_error(kern_return_t error)
{
char const* err_string = mach_error_string(error);
StringView const err_view(err_string, strlen(err_string));
return Error::from_string_view(err_view);
}
static Error bootstrap_error_to_error(kern_return_t error)
{
char const* err_string = bootstrap_strerror(error);
StringView const err_view(err_string, strlen(err_string));
return Error::from_string_view(err_view);
}
MachPort::MachPort(PortRight right, mach_port_t port)
: m_right(right)
, m_port(port)
{
}
MachPort::~MachPort()
{
unref_port();
}
MachPort::MachPort(MachPort&& other)
: m_right(other.m_right)
, m_port(other.release())
{
}
MachPort& MachPort::operator=(MachPort&& other)
{
if (this != &other) {
unref_port();
m_right = other.m_right;
m_port = other.release();
}
return *this;
}
void MachPort::unref_port()
{
if (!MACH_PORT_VALID(m_port))
return;
kern_return_t res = KERN_FAILURE;
switch (m_right) {
case PortRight::Send:
case PortRight::SendOnce:
case PortRight::DeadName:
res = mach_port_deallocate(mach_task_self(), m_port);
break;
case PortRight::Receive:
case PortRight::PortSet:
res = mach_port_mod_refs(mach_task_self(), m_port, to_underlying(m_right), -1);
break;
}
VERIFY(res == KERN_SUCCESS);
}
ErrorOr<MachPort> MachPort::create_with_right(PortRight right)
{
mach_port_t port = MACH_PORT_NULL;
auto const ret = mach_port_allocate(mach_task_self(), to_underlying(right), &port);
if (ret != KERN_SUCCESS) {
dbgln("Unable to allocate port with right: {}", to_underlying(right));
return mach_error_to_error(ret);
}
return MachPort(right, port);
}
MachPort MachPort::adopt_right(mach_port_t port, PortRight right)
{
return MachPort(right, port);
}
mach_port_t MachPort::release()
{
return exchange(m_port, MACH_PORT_NULL);
}
ErrorOr<MachPort> MachPort::insert_right(MessageRight right)
{
auto const ret = mach_port_insert_right(mach_task_self(), m_port, m_port, to_underlying(right));
if (ret != KERN_SUCCESS) {
dbgln("Unable to insert message right: {}", to_underlying(right));
return mach_error_to_error(ret);
}
return MachPort(associated_port_right(right), m_port);
}
#if defined(AK_OS_MACOS)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
// bootstrap_register has been deprecated since macOS 10.5, but rules are more 'guidelines' than actual rules
ErrorOr<void> MachPort::register_with_bootstrap_server(ByteString const& service_name)
{
if (service_name.length() > sizeof(name_t) - 1)
return Error::from_errno(E2BIG);
auto const ret = bootstrap_register(bootstrap_port, const_cast<char*>(service_name.characters()), m_port);
if (ret != KERN_SUCCESS) {
dbgln("Unable to register {} with bootstrap on port {:p}", service_name, m_port);
return bootstrap_error_to_error(ret);
}
return {};
}
# pragma GCC diagnostic pop
ErrorOr<MachPort> MachPort::look_up_from_bootstrap_server(ByteString const& service_name)
{
if (service_name.length() > sizeof(name_t) - 1)
return Error::from_errno(E2BIG);
mach_port_t port = MACH_PORT_NULL;
auto const ret = bootstrap_look_up(bootstrap_port, service_name.characters(), &port);
if (ret != KERN_SUCCESS) {
dbgln("Unable to look up service {} in bootstrap", service_name);
return bootstrap_error_to_error(ret);
}
return MachPort(PortRight::Send, port);
}
#endif
}

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@ -0,0 +1,82 @@
/*
* Copyright (c) 2024, Andrew Kaster <akaster@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Platform.h>
#ifndef AK_OS_MACH
# error "MachPort is only available on Mach platforms"
#endif
#include <AK/Error.h>
#include <AK/Noncopyable.h>
#include <mach/mach.h>
namespace Core {
// https://www.gnu.org/software/hurd/gnumach-doc/Major-Concepts.html#Major-Concepts
class MachPort {
AK_MAKE_NONCOPYABLE(MachPort);
public:
// https://www.gnu.org/software/hurd/gnumach-doc/Exchanging-Port-Rights.html#Exchanging-Port-Rights
enum class PortRight : mach_port_right_t {
Send = MACH_PORT_RIGHT_SEND,
Receive = MACH_PORT_RIGHT_RECEIVE,
SendOnce = MACH_PORT_RIGHT_SEND_ONCE,
PortSet = MACH_PORT_RIGHT_PORT_SET,
DeadName = MACH_PORT_RIGHT_DEAD_NAME,
};
enum class MessageRight : mach_msg_type_name_t {
MoveReceive = MACH_MSG_TYPE_MOVE_RECEIVE,
MoveSend = MACH_MSG_TYPE_MOVE_SEND,
MoveSendOnce = MACH_MSG_TYPE_MOVE_SEND_ONCE,
CopySend = MACH_MSG_TYPE_COPY_SEND,
MakeSend = MACH_MSG_TYPE_MAKE_SEND,
MakeSendOnce = MACH_MSG_TYPE_MAKE_SEND_ONCE,
#if defined(AK_OS_MACOS)
CopyReceive = MACH_MSG_TYPE_COPY_RECEIVE,
DisposeReceive = MACH_MSG_TYPE_DISPOSE_RECEIVE,
DisposeSend = MACH_MSG_TYPE_DISPOSE_SEND,
DisposeSendOnce = MACH_MSG_TYPE_DISPOSE_SEND_ONCE,
#endif
};
MachPort() = default;
MachPort(MachPort&& other);
MachPort& operator=(MachPort&& other);
~MachPort();
mach_port_t release();
static ErrorOr<MachPort> create_with_right(PortRight);
static MachPort adopt_right(mach_port_t, PortRight);
ErrorOr<MachPort> insert_right(MessageRight);
#if defined(AK_OS_MACOS)
// https://opensource.apple.com/source/launchd/launchd-842.92.1/liblaunch/bootstrap.h.auto.html
static ErrorOr<MachPort> look_up_from_bootstrap_server(ByteString const& service_name);
ErrorOr<void> register_with_bootstrap_server(ByteString const& service_name);
#endif
// FIXME: mach_msg wrapper? For now just let the owner poke into the internals
mach_port_t port() { return m_port; }
private:
MachPort(PortRight, mach_port_t);
void unref_port();
PortRight m_right { PortRight::DeadName };
mach_port_t m_port { MACH_PORT_NULL };
};
Error mach_error_to_error(kern_return_t error);
}