Commit a work-in-progress system runtime for Mac OS X which won't
do anything right now.  Add a few new methods to the Thread base
class which HistoryThread needs.  I think I updated all the 
CMakeLists files correctly for the new plugin.

llvm-svn: 194756
diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp
new file mode 100644
index 0000000..ba52ce5
--- /dev/null
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp
@@ -0,0 +1,422 @@
+//===-- SystemRuntimeMacOSX.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/Breakpoint/StoppointCallbackContext.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Core/ModuleSpec.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/DataExtractor.h"
+#include "lldb/Core/DataBufferHeap.h"
+#include "lldb/Core/Section.h"
+#include "lldb/Expression/ClangFunction.h"
+#include "lldb/Expression/ClangUtilityFunction.h"
+#include "lldb/Host/FileSpec.h"
+#include "lldb/Symbol/ObjectFile.h"
+#include "lldb/Symbol/SymbolContext.h"
+#include "Plugins/Process/Utility/HistoryThread.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Thread.h"
+
+
+#include "SystemRuntimeMacOSX.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+//----------------------------------------------------------------------
+// Create an instance of this class. This function is filled into
+// the plugin info class that gets handed out by the plugin factory and
+// allows the lldb to instantiate an instance of this class.
+//----------------------------------------------------------------------
+SystemRuntime *
+SystemRuntimeMacOSX::CreateInstance (Process* process)
+{
+    bool create = false;
+    if (!create)
+    {
+        create = true;
+        Module* exe_module = process->GetTarget().GetExecutableModulePointer();
+        if (exe_module)
+        {
+            ObjectFile *object_file = exe_module->GetObjectFile();
+            if (object_file)
+            {
+                create = (object_file->GetStrata() == ObjectFile::eStrataUser);
+            }
+        }
+        
+        if (create)
+        {
+            const llvm::Triple &triple_ref = process->GetTarget().GetArchitecture().GetTriple();
+            switch (triple_ref.getOS())
+            {
+                case llvm::Triple::Darwin:
+                case llvm::Triple::MacOSX:
+                case llvm::Triple::IOS:
+                    create = triple_ref.getVendor() == llvm::Triple::Apple;
+                    break;
+                default:
+                    create = false;
+                    break;
+            }
+        }
+    }
+    
+    if (create)
+        return new SystemRuntimeMacOSX (process);
+    return NULL;
+}
+
+//----------------------------------------------------------------------
+// Constructor
+//----------------------------------------------------------------------
+SystemRuntimeMacOSX::SystemRuntimeMacOSX (Process* process) :
+    SystemRuntime(process),
+    m_break_id(LLDB_INVALID_BREAK_ID),
+    m_mutex(Mutex::eMutexTypeRecursive)
+{
+    m_ldi_header.initialized = 0;
+}
+
+//----------------------------------------------------------------------
+// Destructor
+//----------------------------------------------------------------------
+SystemRuntimeMacOSX::~SystemRuntimeMacOSX()
+{
+    Clear (true);
+}
+
+//----------------------------------------------------------------------
+// Clear out the state of this class.
+//----------------------------------------------------------------------
+void
+SystemRuntimeMacOSX::Clear (bool clear_process)
+{
+    Mutex::Locker locker(m_mutex);
+
+    if (m_process->IsAlive() && LLDB_BREAK_ID_IS_VALID(m_break_id))
+        m_process->ClearBreakpointSiteByID(m_break_id);
+
+    if (clear_process)
+        m_process = NULL;
+    m_break_id = LLDB_INVALID_BREAK_ID;
+    m_ldi_header.initialized = 0;
+}
+
+
+void 
+SystemRuntimeMacOSX::DidAttach ()
+{
+}
+
+void 
+SystemRuntimeMacOSX::DidLaunch ()
+{
+}
+
+void
+SystemRuntimeMacOSX::ModulesDidLoad (ModuleList &module_list)
+{
+}
+
+bool
+SystemRuntimeMacOSX::LdiHeadersInitialized ()
+{
+    ParseLdiHeaders();
+    return m_ldi_header.initialized;
+}
+
+void
+SystemRuntimeMacOSX::ParseLdiHeaders ()
+{
+    if (m_ldi_header.initialized)
+        return;
+    static ConstString ldi_header_symbol ("ldi_infos");
+    SymbolContextList sc_list;
+    if (m_process->GetTarget().GetImages().FindSymbolsWithNameAndType (ldi_header_symbol, eSymbolTypeData, sc_list) > 0)
+    {
+        SymbolContext sc;
+        sc_list.GetContextAtIndex (0, sc);
+        AddressRange addr_range;
+        sc.GetAddressRange (eSymbolContextSymbol, 0, false, addr_range);
+
+        Error error;
+        Address ldi_header_addr = addr_range.GetBaseAddress();
+        uint8_t version_buf[6];   // version, ldi_header_size, initialized fields
+        DataExtractor data (version_buf, sizeof(version_buf), m_process->GetByteOrder(), m_process->GetAddressByteSize());
+        const size_t count = sizeof (version_buf);
+        const bool prefer_file_cache = false;
+        if (m_process->GetTarget().ReadMemory (ldi_header_addr, prefer_file_cache, version_buf, count, error) == sizeof (version_buf))
+        {
+            int version, initialized, ldi_header_size;
+            offset_t offset = 0;
+            version = data.GetU16(&offset);
+            ldi_header_size = data.GetU16(&offset);
+            initialized = data.GetU16(&offset);
+            if (initialized)
+            {
+                DataBufferHeap ldi_header (ldi_header_size, 0);
+                DataExtractor ldi_extractor (ldi_header.GetBytes(), ldi_header.GetByteSize(), m_process->GetByteOrder(), m_process->GetAddressByteSize());
+                if (m_process->GetTarget().ReadMemory (ldi_header_addr, prefer_file_cache, ldi_header.GetBytes(), ldi_header.GetByteSize(), error) == ldi_header.GetByteSize())
+                {
+                    offset = 0;
+                    m_ldi_header.version = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.ldi_header_size = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.initialized = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.queue_size = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_size = ldi_extractor.GetU16(&offset);
+
+                    // 6 bytes of padding here
+                    offset += 6;
+
+                    m_ldi_header.queues_head_ptr_address = ldi_extractor.GetU64(&offset);
+                    m_ldi_header.items_head_ptr_address = ldi_extractor.GetU64(&offset);
+
+                    m_ldi_header.queue_offsets.next = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.queue_offsets.prev = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.queue_offsets.queue_id = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.queue_offsets.current_item_ptr = ldi_extractor.GetU16(&offset);
+
+                    m_ldi_header.item_offsets.next = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.prev = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.type = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.identifier = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.stop_id = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.backtrace_length = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.backtrace_ptr = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.thread_name_ptr = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.queue_name_ptr = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.unique_thread_id = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.pthread_id = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.enqueueing_thread_dispatch_queue_t = ldi_extractor.GetU16(&offset);
+                    m_ldi_header.item_offsets.enqueueing_thread_dispatch_block_ptr = ldi_extractor.GetU16(&offset);
+                    
+                }
+            }
+        }
+    }
+}
+
+lldb::addr_t
+SystemRuntimeMacOSX::GetQueuesHead ()
+{
+    if (!LdiHeadersInitialized())
+        return LLDB_INVALID_ADDRESS;
+
+    Error error;
+    addr_t queues_head = m_process->ReadPointerFromMemory (m_ldi_header.queues_head_ptr_address, error);
+    if (error.Success() == false || queues_head == LLDB_INVALID_ADDRESS || queues_head == 0)
+        return LLDB_INVALID_ADDRESS;
+
+    return queues_head;
+}
+
+lldb::addr_t
+SystemRuntimeMacOSX::GetItemsHead ()
+{
+    if (!LdiHeadersInitialized())
+        return LLDB_INVALID_ADDRESS;
+
+    Error error;
+    addr_t items_head = m_process->ReadPointerFromMemory (m_ldi_header.items_head_ptr_address, error);
+    if (error.Success() == false || items_head == LLDB_INVALID_ADDRESS || items_head == 0)
+        return LLDB_INVALID_ADDRESS;
+
+    return items_head;
+}
+
+addr_t
+SystemRuntimeMacOSX::GetThreadCreatorItem (ThreadSP thread_sp)
+{
+    addr_t enqueued_item_ptr = thread_sp->GetExtendedBacktraceToken();
+    if (enqueued_item_ptr == LLDB_INVALID_ADDRESS)
+    {
+        if (thread_sp->GetQueueID() == LLDB_INVALID_QUEUE_ID || thread_sp->GetQueueID() == 0)
+            return LLDB_INVALID_ADDRESS;
+    
+        Error error;
+        uint64_t this_thread_queue_id = thread_sp->GetQueueID();
+    
+        addr_t queues_head = GetQueuesHead();
+        if (queues_head == LLDB_INVALID_ADDRESS)
+            return LLDB_INVALID_ADDRESS;
+    
+        // Step through the queues_head linked list looking for a queue matching this thread, if any
+        uint64_t queue_obj_ptr = queues_head;
+        enqueued_item_ptr = LLDB_INVALID_ADDRESS;
+    
+        while (queue_obj_ptr != 0)
+        {
+            uint64_t queue_id = m_process->ReadUnsignedIntegerFromMemory (queue_obj_ptr + m_ldi_header.queue_offsets.queue_id, 8, LLDB_INVALID_ADDRESS, error);
+            if (error.Success() && queue_id != LLDB_INVALID_ADDRESS)
+            {
+                if (queue_id == this_thread_queue_id)
+                {
+                    enqueued_item_ptr = m_process->ReadPointerFromMemory (queue_obj_ptr + m_ldi_header.queue_offsets.current_item_ptr, error);
+                    break;
+                }
+            }
+            queue_obj_ptr = m_process->ReadPointerFromMemory (queue_obj_ptr + m_ldi_header.queue_offsets.next, error);
+            if (error.Success() == false || queue_obj_ptr == LLDB_INVALID_ADDRESS)
+            {
+                break;
+            }
+        }
+    }
+    
+    return enqueued_item_ptr;
+}
+
+SystemRuntimeMacOSX::ArchivedBacktrace
+SystemRuntimeMacOSX::GetLibdispatchExtendedBacktrace (ThreadSP thread_sp)
+{
+    ArchivedBacktrace bt;
+    bt.stop_id = 0;
+    bt.stop_id_is_valid = false;
+    bt.libdispatch_queue_id = LLDB_INVALID_QUEUE_ID;
+
+    addr_t enqueued_item_ptr = GetThreadCreatorItem (thread_sp);
+    
+    if (enqueued_item_ptr == LLDB_INVALID_ADDRESS)
+        return bt;
+
+    Error error;
+    uint32_t ptr_size = m_process->GetTarget().GetArchitecture().GetAddressByteSize();
+
+    uint32_t backtrace_length = m_process->ReadUnsignedIntegerFromMemory (enqueued_item_ptr + m_ldi_header.item_offsets.backtrace_length, 4, 0, error);
+    addr_t pc_array_address = m_process->ReadPointerFromMemory (enqueued_item_ptr + m_ldi_header.item_offsets.backtrace_ptr, error);
+
+    if (backtrace_length == 0 || pc_array_address == LLDB_INVALID_ADDRESS)
+        return bt;
+
+    for (uint32_t idx = 0; idx < backtrace_length; idx++)
+    {
+        addr_t pc_val = m_process->ReadPointerFromMemory (pc_array_address + (ptr_size * idx), error);
+        if (error.Success() && pc_val != LLDB_INVALID_ADDRESS)
+        {
+            bt.pcs.push_back (pc_val);
+        }
+    }
+
+    return bt;
+}
+
+const std::vector<ConstString> &
+SystemRuntimeMacOSX::GetExtendedBacktraceTypes ()
+{
+    if (m_types.size () == 0)
+    {
+        m_types.push_back(ConstString("libdispatch"));
+        m_types.push_back(ConstString("pthread"));
+    }
+    return m_types;
+}
+
+void
+SystemRuntimeMacOSX::SetNewThreadQueueName (ThreadSP original_thread_sp, ThreadSP new_extended_thread_sp)
+{
+    addr_t enqueued_item_ptr = GetThreadCreatorItem (original_thread_sp);
+
+    if (enqueued_item_ptr != LLDB_INVALID_ADDRESS)
+    {
+        Error error;
+        addr_t queue_name_ptr = m_process->ReadPointerFromMemory (enqueued_item_ptr + m_ldi_header.item_offsets.queue_name_ptr, error);
+        if (queue_name_ptr != LLDB_INVALID_ADDRESS && error.Success())
+        {
+            char namebuf[256];
+            if (m_process->ReadCStringFromMemory (queue_name_ptr, namebuf, sizeof (namebuf), error) > 0 && error.Success())
+            {
+                new_extended_thread_sp->SetQueueName (namebuf);
+            }
+        }
+    }
+}
+
+void
+SystemRuntimeMacOSX::SetNewThreadExtendedBacktraceToken (ThreadSP original_thread_sp, ThreadSP new_extended_thread_sp)
+{
+    addr_t enqueued_item_ptr = GetThreadCreatorItem (original_thread_sp);
+    if (enqueued_item_ptr != LLDB_INVALID_ADDRESS)
+    {
+        Error error;
+        uint64_t further_extended_backtrace = m_process->ReadPointerFromMemory (enqueued_item_ptr + m_ldi_header.item_offsets.enqueueing_thread_dispatch_block_ptr, error);
+        if (error.Success() && further_extended_backtrace != 0 && further_extended_backtrace != LLDB_INVALID_ADDRESS)
+        {
+            new_extended_thread_sp->SetExtendedBacktraceToken (further_extended_backtrace);
+        }
+    }
+}
+
+ThreadSP
+SystemRuntimeMacOSX::GetExtendedBacktraceThread (ThreadSP original_thread_sp, ConstString type)
+{
+    ThreadSP new_extended_thread_sp;
+
+    if (type != ConstString("libdispatch"))
+        return new_extended_thread_sp;
+
+    ArchivedBacktrace bt = GetLibdispatchExtendedBacktrace (original_thread_sp);
+
+    if (bt.pcs.size() == 0)
+        return new_extended_thread_sp;
+
+    new_extended_thread_sp.reset (new HistoryThread (*m_process, bt.pcs, bt.stop_id, bt.stop_id_is_valid));
+
+    SetNewThreadQueueName(original_thread_sp, new_extended_thread_sp);
+    SetNewThreadExtendedBacktraceToken(original_thread_sp, new_extended_thread_sp);
+
+    return new_extended_thread_sp;
+}
+
+
+void
+SystemRuntimeMacOSX::Initialize()
+{
+    PluginManager::RegisterPlugin (GetPluginNameStatic(),
+                                   GetPluginDescriptionStatic(),
+                                   CreateInstance);
+}
+
+void
+SystemRuntimeMacOSX::Terminate()
+{
+    PluginManager::UnregisterPlugin (CreateInstance);
+}
+
+
+lldb_private::ConstString
+SystemRuntimeMacOSX::GetPluginNameStatic()
+{
+    static ConstString g_name("systemruntime-macosx");
+    return g_name;
+}
+
+const char *
+SystemRuntimeMacOSX::GetPluginDescriptionStatic()
+{
+    return "System runtime plugin for Mac OS X native libraries.";
+}
+
+
+//------------------------------------------------------------------
+// PluginInterface protocol
+//------------------------------------------------------------------
+lldb_private::ConstString
+SystemRuntimeMacOSX::GetPluginName()
+{
+    return GetPluginNameStatic();
+}
+
+uint32_t
+SystemRuntimeMacOSX::GetPluginVersion()
+{
+    return 1;
+}