[Lldb-commits] [lldb] r197620 - Code reorganization in PlatformDarwin for how the libdispatch
Jason Molenda
jmolenda at apple.com
Wed Dec 18 14:52:34 PST 2013
Author: jmolenda
Date: Wed Dec 18 16:52:34 2013
New Revision: 197620
URL: http://llvm.org/viewvc/llvm-project?rev=197620&view=rev
Log:
Code reorganization in PlatformDarwin for how the libdispatch
offsets structure is read & saved in the platform object -- soon
we'll be getting more than the queue name offset out of this
structure so we'll need to reuse the information in other methods.
Modified:
lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp
lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.h
Modified: lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp?rev=197620&r1=197619&r2=197620&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp (original)
+++ lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp Wed Dec 18 16:52:34 2013
@@ -39,7 +39,8 @@ using namespace lldb_private;
PlatformDarwin::PlatformDarwin (bool is_host) :
PlatformPOSIX(is_host), // This is the local host platform
m_developer_directory (),
- m_dispatch_queue_offsets_addr (LLDB_INVALID_ADDRESS)
+ m_dispatch_queue_offsets_addr (LLDB_INVALID_ADDRESS),
+ m_libdispatch_offsets()
{
}
@@ -873,89 +874,89 @@ PlatformDarwin::GetQueueNameForThreadQAd
if (thread_dispatch_qaddr == LLDB_INVALID_ADDRESS || thread_dispatch_qaddr == 0 || process == NULL)
return "";
- Target &target = process->GetTarget();
+ ReadLibdispatchOffsets (process);
+ if (m_libdispatch_offsets.IsValid ())
+ {
+ Error error;
+ addr_t queue_addr = process->ReadPointerFromMemory (thread_dispatch_qaddr, error);
+ if (error.Success())
+ {
+ if (m_libdispatch_offsets.dqo_version >= 4)
+ {
+ // libdispatch versions 4+, pointer to dispatch name is in the
+ // queue structure.
+ addr_t pointer_to_label_address = queue_addr + m_libdispatch_offsets.dqo_label;
+ addr_t label_addr = process->ReadPointerFromMemory (pointer_to_label_address, error);
+ if (error.Success())
+ {
+ process->ReadCStringFromMemory (label_addr, dispatch_queue_name, error);
+ }
+ }
+ else
+ {
+ // libdispatch versions 1-3, dispatch name is a fixed width char array
+ // in the queue structure.
+ addr_t label_addr = queue_addr + m_libdispatch_offsets.dqo_label;
+ dispatch_queue_name.resize (m_libdispatch_offsets.dqo_label_size, '\0');
+ size_t bytes_read = process->ReadMemory (label_addr, &dispatch_queue_name[0], m_libdispatch_offsets.dqo_label_size, error);
+ if (bytes_read < m_libdispatch_offsets.dqo_label_size)
+ dispatch_queue_name.erase (bytes_read);
+ }
+ }
+ }
+ return dispatch_queue_name;
+}
+
+void
+PlatformDarwin::ReadLibdispatchOffsetsAddress (Process *process)
+{
+ if (m_dispatch_queue_offsets_addr != LLDB_INVALID_ADDRESS)
+ return;
+
+ static ConstString g_dispatch_queue_offsets_symbol_name ("dispatch_queue_offsets");
+ const Symbol *dispatch_queue_offsets_symbol = NULL;
- // Cache the dispatch_queue_offsets_addr value so we don't always have
- // to look it up
- if (m_dispatch_queue_offsets_addr == LLDB_INVALID_ADDRESS)
- {
- static ConstString g_dispatch_queue_offsets_symbol_name ("dispatch_queue_offsets");
- const Symbol *dispatch_queue_offsets_symbol = NULL;
-
- // libdispatch symbols were in libSystem.B.dylib up through Mac OS X 10.6 ("Snow Leopard")
- ModuleSpec libSystem_module_spec (FileSpec("libSystem.B.dylib", false));
- ModuleSP module_sp(target.GetImages().FindFirstModule (libSystem_module_spec));
+ // libdispatch symbols were in libSystem.B.dylib up through Mac OS X 10.6 ("Snow Leopard")
+ ModuleSpec libSystem_module_spec (FileSpec("libSystem.B.dylib", false));
+ ModuleSP module_sp(process->GetTarget().GetImages().FindFirstModule (libSystem_module_spec));
+ if (module_sp)
+ dispatch_queue_offsets_symbol = module_sp->FindFirstSymbolWithNameAndType (g_dispatch_queue_offsets_symbol_name, eSymbolTypeData);
+
+ // libdispatch symbols are in their own dylib as of Mac OS X 10.7 ("Lion") and later
+ if (dispatch_queue_offsets_symbol == NULL)
+ {
+ ModuleSpec libdispatch_module_spec (FileSpec("libdispatch.dylib", false));
+ module_sp = process->GetTarget().GetImages().FindFirstModule (libdispatch_module_spec);
if (module_sp)
dispatch_queue_offsets_symbol = module_sp->FindFirstSymbolWithNameAndType (g_dispatch_queue_offsets_symbol_name, eSymbolTypeData);
-
- // libdispatch symbols are in their own dylib as of Mac OS X 10.7 ("Lion") and later
- if (dispatch_queue_offsets_symbol == NULL)
- {
- ModuleSpec libdispatch_module_spec (FileSpec("libdispatch.dylib", false));
- module_sp = target.GetImages().FindFirstModule (libdispatch_module_spec);
- if (module_sp)
- dispatch_queue_offsets_symbol = module_sp->FindFirstSymbolWithNameAndType (g_dispatch_queue_offsets_symbol_name, eSymbolTypeData);
- }
- if (dispatch_queue_offsets_symbol)
- m_dispatch_queue_offsets_addr = dispatch_queue_offsets_symbol->GetAddress().GetLoadAddress(&target);
-
- if (m_dispatch_queue_offsets_addr == LLDB_INVALID_ADDRESS)
- return "";
}
+ if (dispatch_queue_offsets_symbol)
+ m_dispatch_queue_offsets_addr = dispatch_queue_offsets_symbol->GetAddress().GetLoadAddress(&process->GetTarget());
+}
+
+void
+PlatformDarwin::ReadLibdispatchOffsets (Process *process)
+{
+ if (m_libdispatch_offsets.IsValid())
+ return;
- uint8_t memory_buffer[8];
+ ReadLibdispatchOffsetsAddress (process);
+
+ uint8_t memory_buffer[sizeof (struct LibdispatchOffsets)];
DataExtractor data (memory_buffer,
sizeof(memory_buffer),
- target.GetArchitecture().GetByteOrder(),
- target.GetArchitecture().GetAddressByteSize());
-
- // Excerpt from src/queue_private.h
- // version 4 of this struct first appears in Mac OS X 10.9 ("Mavericks") and iOS 7.
- // TODO When version 1-3 no longer needs to be supported, the dqo_label offset should be
- // read from the inferior one time and saved in an ivar like m_dispatch_queue_offsets_addr.
- struct dispatch_queue_offsets_s
- {
- uint16_t dqo_version;
- uint16_t dqo_label; // in version 1-3, offset to string; in version 4+, offset to a pointer to a string
- uint16_t dqo_label_size; // in version 1-3, length of string; in version 4+, size of a (void*) in this process
- } dispatch_queue_offsets;
+ process->GetTarget().GetArchitecture().GetByteOrder(),
+ process->GetTarget().GetArchitecture().GetAddressByteSize());
Error error;
- if (process->ReadMemory (m_dispatch_queue_offsets_addr, memory_buffer, sizeof(dispatch_queue_offsets), error) == sizeof(dispatch_queue_offsets))
+ if (process->ReadMemory (m_dispatch_queue_offsets_addr, memory_buffer, sizeof(memory_buffer), error) == sizeof(memory_buffer))
{
lldb::offset_t data_offset = 0;
- if (data.GetU16(&data_offset, &dispatch_queue_offsets.dqo_version, sizeof(dispatch_queue_offsets)/sizeof(uint16_t)))
- {
- if (process->ReadMemory (thread_dispatch_qaddr, &memory_buffer, data.GetAddressByteSize(), error) == data.GetAddressByteSize())
- {
- data_offset = 0;
- lldb::addr_t queue_addr = data.GetAddress(&data_offset);
- if (dispatch_queue_offsets.dqo_version >= 4)
- {
- // libdispatch versions 4+, pointer to dispatch name is in the
- // queue structure.
- lldb::addr_t pointer_to_label_address = queue_addr + dispatch_queue_offsets.dqo_label;
- if (process->ReadMemory (pointer_to_label_address, &memory_buffer, data.GetAddressByteSize(), error) == data.GetAddressByteSize())
- {
- data_offset = 0;
- lldb::addr_t label_addr = data.GetAddress(&data_offset);
- process->ReadCStringFromMemory (label_addr, dispatch_queue_name, error);
- }
- }
- else
- {
- // libdispatch versions 1-3, dispatch name is a fixed width char array
- // in the queue structure.
- lldb::addr_t label_addr = queue_addr + dispatch_queue_offsets.dqo_label;
- dispatch_queue_name.resize(dispatch_queue_offsets.dqo_label_size, '\0');
- size_t bytes_read = process->ReadMemory (label_addr, &dispatch_queue_name[0], dispatch_queue_offsets.dqo_label_size, error);
- if (bytes_read < dispatch_queue_offsets.dqo_label_size)
- dispatch_queue_name.erase (bytes_read);
- }
- }
- }
+
+ // The struct LibdispatchOffsets is a series of uint16_t's - extract them all
+ // in one big go.
+ data.GetU16 (&data_offset, &m_libdispatch_offsets.dqo_version, sizeof (struct LibdispatchOffsets) / sizeof (uint16_t));
}
- return dispatch_queue_name;
}
lldb::queue_id_t
Modified: lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.h
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.h?rev=197620&r1=197619&r2=197620&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.h (original)
+++ lldb/trunk/source/Plugins/Platform/MacOSX/PlatformDarwin.h Wed Dec 18 16:52:34 2013
@@ -134,6 +134,13 @@ public:
GetResumeCountForLaunchInfo (lldb_private::ProcessLaunchInfo &launch_info);
protected:
+
+ lldb::addr_t
+ ReadLibdispatchOffsetsAddress (lldb_private::Process *process);
+
+ void
+ ReadLibdispatchOffsets (lldb_private::Process *process);
+
virtual lldb_private::Error
GetSharedModuleWithLocalCache (const lldb_private::ModuleSpec &module_spec,
lldb::ModuleSP &module_sp,
@@ -141,9 +148,50 @@ protected:
lldb::ModuleSP *old_module_sp_ptr,
bool *did_create_ptr);
- std::string m_developer_directory;
- lldb::addr_t m_dispatch_queue_offsets_addr;
-
+ // Based on libdispatch src/queue_private.h, struct dispatch_queue_offsets_s
+ // With dqo_version 1-3, the dqo_label field is a per-queue value and cannot be cached.
+ // With dqo_version 4 (Mac OS X 10.9 / iOS 7), dqo_label is a constant value that can be cached.
+ struct LibdispatchOffsets
+ {
+ uint16_t dqo_version;
+ uint16_t dqo_label;
+ uint16_t dqo_label_size;
+ uint16_t dqo_flags;
+ uint16_t dqo_flags_size;
+ uint16_t dqo_serialnum;
+ uint16_t dqo_serialnum_size;
+ uint16_t dqo_width;
+ uint16_t dqo_width_size;
+ uint16_t dqo_running;
+ uint16_t dqo_running_size;
+
+ LibdispatchOffsets ()
+ {
+ dqo_version = UINT16_MAX;
+ dqo_flags = UINT16_MAX;
+ dqo_serialnum = UINT16_MAX;
+ dqo_label = UINT16_MAX;
+ dqo_width = UINT16_MAX;
+ dqo_running = UINT16_MAX;
+ };
+
+ bool
+ IsValid ()
+ {
+ return dqo_version != UINT16_MAX;
+ }
+
+ bool
+ LabelIsValid ()
+ {
+ return dqo_label != UINT16_MAX;
+ }
+ };
+
+ std::string m_developer_directory;
+ lldb::addr_t m_dispatch_queue_offsets_addr;
+ struct LibdispatchOffsets m_libdispatch_offsets;
+
const char *
GetDeveloperDirectory();
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