llvm-project/lldb/source/Core/Broadcaster.cpp

500 lines
14 KiB
C++

//===-- Broadcaster.cpp -----------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Core/Broadcaster.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Core/Log.h"
#include "lldb/Core/Event.h"
#include "lldb/Core/StreamString.h"
#include "lldb/lldb-private-log.h"
using namespace lldb;
using namespace lldb_private;
Broadcaster::Broadcaster (BroadcasterManager *manager, const char *name) :
m_broadcaster_name (name),
m_listeners (),
m_listeners_mutex (Mutex::eMutexTypeRecursive),
m_hijacking_listeners(),
m_hijacking_masks(),
m_manager (manager)
{
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_OBJECT));
if (log)
log->Printf ("%p Broadcaster::Broadcaster(\"%s\")", this, m_broadcaster_name.AsCString());
}
Broadcaster::~Broadcaster()
{
LogSP log (lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_OBJECT));
if (log)
log->Printf ("%p Broadcaster::~Broadcaster(\"%s\")", this, m_broadcaster_name.AsCString());
Clear();
}
void
Broadcaster::CheckInWithManager ()
{
if (m_manager != NULL)
{
m_manager->SignUpListenersForBroadcaster(*this);
}
}
void
Broadcaster::Clear()
{
Mutex::Locker listeners_locker(m_listeners_mutex);
// Make sure the listener forgets about this broadcaster. We do
// this in the broadcaster in case the broadcaster object initiates
// the removal.
collection::iterator pos, end = m_listeners.end();
for (pos = m_listeners.begin(); pos != end; ++pos)
pos->first->BroadcasterWillDestruct (this);
m_listeners.clear();
}
const ConstString &
Broadcaster::GetBroadcasterName ()
{
return m_broadcaster_name;
}
bool
Broadcaster::GetEventNames (Stream &s, uint32_t event_mask, bool prefix_with_broadcaster_name) const
{
uint32_t num_names_added = 0;
if (event_mask && !m_event_names.empty())
{
event_names_map::const_iterator end = m_event_names.end();
for (uint32_t bit=1u, mask=event_mask; mask != 0 && bit != 0; bit <<= 1, mask >>= 1)
{
if (mask & 1)
{
event_names_map::const_iterator pos = m_event_names.find(bit);
if (pos != end)
{
if (num_names_added > 0)
s.PutCString(", ");
if (prefix_with_broadcaster_name)
{
s.PutCString (m_broadcaster_name.GetCString());
s.PutChar('.');
}
s.PutCString(pos->second.c_str());
++num_names_added;
}
}
}
}
return num_names_added > 0;
}
void
Broadcaster::AddInitialEventsToListener (Listener *listener, uint32_t requested_events)
{
}
uint32_t
Broadcaster::AddListener (Listener* listener, uint32_t event_mask)
{
if (listener == NULL)
return 0;
Mutex::Locker locker(m_listeners_mutex);
collection::iterator pos, end = m_listeners.end();
collection::iterator existing_pos = end;
// See if we already have this listener, and if so, update its mask
uint32_t taken_event_types = 0;
for (pos = m_listeners.begin(); pos != end; ++pos)
{
if (pos->first == listener)
existing_pos = pos;
// For now don't descriminate on who gets what
// FIXME: Implement "unique listener for this bit" mask
// taken_event_types |= pos->second;
}
// Each event bit in a Broadcaster object can only be used
// by one listener
uint32_t available_event_types = ~taken_event_types & event_mask;
if (available_event_types)
{
// If we didn't find our listener, add it
if (existing_pos == end)
{
// Grant a new listener the available event bits
m_listeners.push_back(std::make_pair(listener, available_event_types));
}
else
{
// Grant the existing listener the available event bits
existing_pos->second |= available_event_types;
}
// Individual broadcasters decide whether they have outstanding data when a
// listener attaches, and insert it into the listener with this method.
AddInitialEventsToListener (listener, available_event_types);
}
// Return the event bits that were granted to the listener
return available_event_types;
}
bool
Broadcaster::EventTypeHasListeners (uint32_t event_type)
{
Mutex::Locker locker (m_listeners_mutex);
if (m_hijacking_listeners.size() > 0 && event_type & m_hijacking_masks.back())
return true;
if (m_listeners.empty())
return false;
collection::iterator pos, end = m_listeners.end();
for (pos = m_listeners.begin(); pos != end; ++pos)
{
if (pos->second & event_type)
return true;
}
return false;
}
bool
Broadcaster::RemoveListener (Listener* listener, uint32_t event_mask)
{
Mutex::Locker locker(m_listeners_mutex);
collection::iterator pos, end = m_listeners.end();
// See if we already have this listener, and if so, update its mask
for (pos = m_listeners.begin(); pos != end; ++pos)
{
if (pos->first == listener)
{
// Relinquish all event bits in "event_mask"
pos->second &= ~event_mask;
// If all bits have been relinquished then remove this listener
if (pos->second == 0)
m_listeners.erase (pos);
return true;
}
}
return false;
}
void
Broadcaster::BroadcastEvent (EventSP &event_sp)
{
return PrivateBroadcastEvent (event_sp, false);
}
void
Broadcaster::BroadcastEventIfUnique (EventSP &event_sp)
{
return PrivateBroadcastEvent (event_sp, true);
}
void
Broadcaster::PrivateBroadcastEvent (EventSP &event_sp, bool unique)
{
// Can't add a NULL event...
if (event_sp.get() == NULL)
return;
// Update the broadcaster on this event
event_sp->SetBroadcaster (this);
const uint32_t event_type = event_sp->GetType();
Mutex::Locker event_types_locker(m_listeners_mutex);
Listener *hijacking_listener = NULL;
if (!m_hijacking_listeners.empty())
{
assert (!m_hijacking_masks.empty());
hijacking_listener = m_hijacking_listeners.back();
if ((event_type & m_hijacking_masks.back()) == 0)
hijacking_listener = NULL;
}
LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EVENTS));
if (log)
{
StreamString event_description;
event_sp->Dump (&event_description);
log->Printf ("%p Broadcaster(\"%s\")::BroadcastEvent (event_sp = {%s}, unique =%i) hijack = %p",
this,
m_broadcaster_name.AsCString(""),
event_description.GetData(),
unique,
hijacking_listener);
}
if (hijacking_listener)
{
if (unique && hijacking_listener->PeekAtNextEventForBroadcasterWithType (this, event_type))
return;
hijacking_listener->AddEvent (event_sp);
}
else
{
collection::iterator pos, end = m_listeners.end();
// Iterate through all listener/mask pairs
for (pos = m_listeners.begin(); pos != end; ++pos)
{
// If the listener's mask matches any bits that we just set, then
// put the new event on its event queue.
if (event_type & pos->second)
{
if (unique && pos->first->PeekAtNextEventForBroadcasterWithType (this, event_type))
continue;
pos->first->AddEvent (event_sp);
}
}
}
}
void
Broadcaster::BroadcastEvent (uint32_t event_type, EventData *event_data)
{
EventSP event_sp (new Event (event_type, event_data));
PrivateBroadcastEvent (event_sp, false);
}
void
Broadcaster::BroadcastEventIfUnique (uint32_t event_type, EventData *event_data)
{
EventSP event_sp (new Event (event_type, event_data));
PrivateBroadcastEvent (event_sp, true);
}
bool
Broadcaster::HijackBroadcaster (Listener *listener, uint32_t event_mask)
{
Mutex::Locker event_types_locker(m_listeners_mutex);
LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EVENTS));
if (log)
{
log->Printf ("%p Broadcaster(\"%s\")::HijackBroadcaster (listener(\"%s\")=%p)",
this,
m_broadcaster_name.AsCString(""),
listener->m_name.c_str(),
listener);
}
m_hijacking_listeners.push_back(listener);
m_hijacking_masks.push_back(event_mask);
return true;
}
void
Broadcaster::RestoreBroadcaster ()
{
Mutex::Locker event_types_locker(m_listeners_mutex);
LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EVENTS));
if (log)
{
Listener *listener = m_hijacking_listeners.back();
log->Printf ("%p Broadcaster(\"%s\")::RestoreBroadcaster (about to pop listener(\"%s\")=%p)",
this,
m_broadcaster_name.AsCString(""),
listener->m_name.c_str(),
listener);
}
m_hijacking_listeners.pop_back();
m_hijacking_masks.pop_back();
}
ConstString &
Broadcaster::GetBroadcasterClass() const
{
static ConstString class_name ("lldb.anonymous");
return class_name;
}
BroadcastEventSpec::BroadcastEventSpec (const BroadcastEventSpec &rhs) :
m_broadcaster_class (rhs.m_broadcaster_class),
m_event_bits (rhs.m_event_bits)
{
}
bool
BroadcastEventSpec::operator< (const BroadcastEventSpec &rhs) const
{
if (GetBroadcasterClass() == rhs.GetBroadcasterClass())
{
return GetEventBits() < rhs.GetEventBits();
}
else
{
return GetBroadcasterClass() < rhs.GetBroadcasterClass();
}
}
const BroadcastEventSpec &
BroadcastEventSpec::operator= (const BroadcastEventSpec &rhs)
{
m_broadcaster_class = rhs.m_broadcaster_class;
m_event_bits = rhs.m_event_bits;
return *this;
}
BroadcasterManager::BroadcasterManager() :
m_manager_mutex(Mutex::eMutexTypeRecursive)
{
}
uint32_t
BroadcasterManager::RegisterListenerForEvents (Listener &listener, BroadcastEventSpec event_spec)
{
Mutex::Locker locker(m_manager_mutex);
collection::iterator iter = m_event_map.begin(), end_iter = m_event_map.end();
uint32_t available_bits = event_spec.GetEventBits();
while (iter != end_iter
&& (iter = find_if (iter, end_iter, BroadcasterClassMatches(event_spec.GetBroadcasterClass()))) != end_iter)
{
available_bits &= ~((*iter).first.GetEventBits());
iter++;
}
if (available_bits != 0)
{
m_event_map.insert (event_listener_key (BroadcastEventSpec (event_spec.GetBroadcasterClass(), available_bits), &listener));
m_listeners.insert(&listener);
}
return available_bits;
}
bool
BroadcasterManager::UnregisterListenerForEvents (Listener &listener, BroadcastEventSpec event_spec)
{
Mutex::Locker locker(m_manager_mutex);
bool removed_some = false;
if (m_listeners.erase(&listener) == 0)
return false;
ListenerMatchesAndSharedBits predicate (event_spec, listener);
std::vector<BroadcastEventSpec> to_be_readded;
uint32_t event_bits_to_remove = event_spec.GetEventBits();
// Go through the map and delete the exact matches, and build a list of matches that weren't exact to re-add:
while (1)
{
collection::iterator iter, end_iter = m_event_map.end();
iter = find_if (m_event_map.begin(), end_iter, predicate);
if (iter == end_iter)
{
break;
}
else
{
uint32_t iter_event_bits = (*iter).first.GetEventBits();
removed_some = true;
if (event_bits_to_remove != iter_event_bits)
{
uint32_t new_event_bits = iter_event_bits & ~event_bits_to_remove;
to_be_readded.push_back(BroadcastEventSpec (event_spec.GetBroadcasterClass(), new_event_bits));
}
m_event_map.erase (iter);
}
}
// Okay now add back the bits that weren't completely removed:
for (size_t i = 0; i < to_be_readded.size(); i++)
{
m_event_map.insert (event_listener_key (to_be_readded[i], &listener));
}
return removed_some;
}
Listener *
BroadcasterManager::GetListenerForEventSpec (BroadcastEventSpec event_spec) const
{
Mutex::Locker locker(*(const_cast<Mutex *> (&m_manager_mutex)));
collection::const_iterator iter, end_iter = m_event_map.end();
iter = find_if (m_event_map.begin(), end_iter, BroadcastEventSpecMatches (event_spec));
if (iter != end_iter)
return (*iter).second;
else
return NULL;
}
void
BroadcasterManager::RemoveListener (Listener &listener)
{
Mutex::Locker locker(m_manager_mutex);
ListenerMatches predicate (listener);
if (m_listeners.erase (&listener) == 0)
return;
while (1)
{
collection::iterator iter, end_iter = m_event_map.end();
iter = find_if (m_event_map.begin(), end_iter, predicate);
if (iter == end_iter)
break;
else
m_event_map.erase(iter);
}
}
void
BroadcasterManager::SignUpListenersForBroadcaster (Broadcaster &broadcaster)
{
Mutex::Locker locker(m_manager_mutex);
collection::iterator iter = m_event_map.begin(), end_iter = m_event_map.end();
while (iter != end_iter
&& (iter = find_if (iter, end_iter, BroadcasterClassMatches(broadcaster.GetBroadcasterClass()))) != end_iter)
{
(*iter).second->StartListeningForEvents (&broadcaster, (*iter).first.GetEventBits());
iter++;
}
}
void
BroadcasterManager::Clear ()
{
Mutex::Locker locker(m_manager_mutex);
listener_collection::iterator end_iter = m_listeners.end();
for (listener_collection::iterator iter = m_listeners.begin(); iter != end_iter; iter++)
(*iter)->BroadcasterManagerWillDestruct(this);
m_listeners.clear();
m_event_map.clear();
}