1 //===-- DynamicLoaderMacOSXDYLD.cpp -----------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 
11 #include "llvm/Support/MachO.h"
12 
13 #include "lldb/Breakpoint/StoppointCallbackContext.h"
14 #include "lldb/Core/DataBuffer.h"
15 #include "lldb/Core/DataBufferHeap.h"
16 #include "lldb/Core/Log.h"
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/PluginManager.h"
19 #include "lldb/Core/State.h"
20 #include "lldb/Symbol/ObjectFile.h"
21 #include "lldb/Target/ObjCLanguageRuntime.h"
22 #include "lldb/Target/RegisterContext.h"
23 #include "lldb/Target/Target.h"
24 #include "lldb/Target/Thread.h"
25 #include "lldb/Target/ThreadPlanRunToAddress.h"
26 #include "lldb/Target/StackFrame.h"
27 
28 #include "DynamicLoaderMacOSXDYLD.h"
29 
30 //#define ENABLE_DEBUG_PRINTF // COMMENT THIS LINE OUT PRIOR TO CHECKIN
31 #ifdef ENABLE_DEBUG_PRINTF
32 #include <stdio.h>
33 #define DEBUG_PRINTF(fmt, ...) printf(fmt, ## __VA_ARGS__)
34 #else
35 #define DEBUG_PRINTF(fmt, ...)
36 #endif
37 
38 using namespace lldb;
39 using namespace lldb_private;
40 
41 /// FIXME - The ObjC Runtime trampoline handler doesn't really belong here.
42 /// I am putting it here so I can invoke it in the Trampoline code here, but
43 /// it should be moved to the ObjC Runtime support when it is set up.
44 
45 
46 DynamicLoaderMacOSXDYLD::DYLDImageInfo *
47 DynamicLoaderMacOSXDYLD::GetImageInfo (Module *module)
48 {
49     const UUID &module_uuid = module->GetUUID();
50     DYLDImageInfo::collection::iterator pos, end = m_dyld_image_infos.end();
51 
52     // First try just by UUID as it is the safest.
53     if (module_uuid.IsValid())
54     {
55         for (pos = m_dyld_image_infos.begin(); pos != end; ++pos)
56         {
57             if (pos->uuid == module_uuid)
58                 return &(*pos);
59         }
60 
61         if (m_dyld.uuid == module_uuid)
62             return &m_dyld;
63     }
64 
65     // Next try by platform path only for things that don't have a valid UUID
66     // since if a file has a valid UUID in real life it should also in the
67     // dyld info. This is the next safest because the paths in the dyld info
68     // are platform paths, not local paths. For local debugging platform == local
69     // paths.
70     const FileSpec &platform_file_spec = module->GetPlatformFileSpec();
71     for (pos = m_dyld_image_infos.begin(); pos != end; ++pos)
72     {
73         if (pos->file_spec == platform_file_spec && pos->uuid.IsValid() == false)
74             return &(*pos);
75     }
76 
77     if (m_dyld.file_spec == platform_file_spec && m_dyld.uuid.IsValid() == false)
78         return &m_dyld;
79 
80     return NULL;
81 }
82 
83 //----------------------------------------------------------------------
84 // Create an instance of this class. This function is filled into
85 // the plugin info class that gets handed out by the plugin factory and
86 // allows the lldb to instantiate an instance of this class.
87 //----------------------------------------------------------------------
88 DynamicLoader *
89 DynamicLoaderMacOSXDYLD::CreateInstance (Process* process, bool force)
90 {
91     bool create = force;
92     if (!create)
93     {
94         create = true;
95         Module* exe_module = process->GetTarget().GetExecutableModulePointer();
96         if (exe_module)
97         {
98             ObjectFile *object_file = exe_module->GetObjectFile();
99             if (object_file)
100             {
101                 create = (object_file->GetStrata() == ObjectFile::eStrataUser);
102             }
103         }
104 
105         if (create)
106         {
107             const llvm::Triple &triple_ref = process->GetTarget().GetArchitecture().GetTriple();
108             create = triple_ref.getOS() == llvm::Triple::Darwin && triple_ref.getVendor() == llvm::Triple::Apple;
109         }
110     }
111 
112     if (create)
113         return new DynamicLoaderMacOSXDYLD (process);
114     return NULL;
115 }
116 
117 //----------------------------------------------------------------------
118 // Constructor
119 //----------------------------------------------------------------------
120 DynamicLoaderMacOSXDYLD::DynamicLoaderMacOSXDYLD (Process* process) :
121     DynamicLoader(process),
122     m_dyld(),
123     m_dyld_all_image_infos_addr(LLDB_INVALID_ADDRESS),
124     m_dyld_all_image_infos(),
125     m_dyld_all_image_infos_stop_id (UINT32_MAX),
126     m_break_id(LLDB_INVALID_BREAK_ID),
127     m_dyld_image_infos(),
128     m_dyld_image_infos_stop_id (UINT32_MAX),
129     m_mutex(Mutex::eMutexTypeRecursive)
130 {
131 }
132 
133 //----------------------------------------------------------------------
134 // Destructor
135 //----------------------------------------------------------------------
136 DynamicLoaderMacOSXDYLD::~DynamicLoaderMacOSXDYLD()
137 {
138     Clear(true);
139 }
140 
141 //------------------------------------------------------------------
142 /// Called after attaching a process.
143 ///
144 /// Allow DynamicLoader plug-ins to execute some code after
145 /// attaching to a process.
146 //------------------------------------------------------------------
147 void
148 DynamicLoaderMacOSXDYLD::DidAttach ()
149 {
150     PrivateInitialize(m_process);
151     LocateDYLD ();
152     SetNotificationBreakpoint ();
153 }
154 
155 //------------------------------------------------------------------
156 /// Called after attaching a process.
157 ///
158 /// Allow DynamicLoader plug-ins to execute some code after
159 /// attaching to a process.
160 //------------------------------------------------------------------
161 void
162 DynamicLoaderMacOSXDYLD::DidLaunch ()
163 {
164     PrivateInitialize(m_process);
165     LocateDYLD ();
166     SetNotificationBreakpoint ();
167 }
168 
169 
170 //----------------------------------------------------------------------
171 // Clear out the state of this class.
172 //----------------------------------------------------------------------
173 void
174 DynamicLoaderMacOSXDYLD::Clear (bool clear_process)
175 {
176     Mutex::Locker locker(m_mutex);
177 
178     if (m_process->IsAlive() && LLDB_BREAK_ID_IS_VALID(m_break_id))
179         m_process->ClearBreakpointSiteByID(m_break_id);
180 
181     if (clear_process)
182         m_process = NULL;
183     m_dyld.Clear(false);
184     m_dyld_all_image_infos_addr = LLDB_INVALID_ADDRESS;
185     m_dyld_all_image_infos.Clear();
186     m_break_id = LLDB_INVALID_BREAK_ID;
187     m_dyld_image_infos.clear();
188 }
189 
190 //----------------------------------------------------------------------
191 // Check if we have found DYLD yet
192 //----------------------------------------------------------------------
193 bool
194 DynamicLoaderMacOSXDYLD::DidSetNotificationBreakpoint() const
195 {
196     return LLDB_BREAK_ID_IS_VALID (m_break_id);
197 }
198 
199 //----------------------------------------------------------------------
200 // Try and figure out where dyld is by first asking the Process
201 // if it knows (which currently calls down in the the lldb::Process
202 // to get the DYLD info (available on SnowLeopard only). If that fails,
203 // then check in the default addresses.
204 //----------------------------------------------------------------------
205 bool
206 DynamicLoaderMacOSXDYLD::LocateDYLD()
207 {
208     if (m_dyld_all_image_infos_addr == LLDB_INVALID_ADDRESS)
209     {
210         // Check the image info addr as it might point to the
211         // mach header for dyld, or it might point to the
212         // dyld_all_image_infos struct
213         const addr_t shlib_addr = m_process->GetImageInfoAddress ();
214 
215         ByteOrder byte_order = m_process->GetTarget().GetArchitecture().GetByteOrder();
216         uint8_t buf[4];
217         DataExtractor data (buf, sizeof(buf), byte_order, 4);
218         Error error;
219         if (m_process->ReadMemory (shlib_addr, buf, 4, error) == 4)
220         {
221             uint32_t offset = 0;
222             uint32_t magic = data.GetU32 (&offset);
223             switch (magic)
224             {
225             case llvm::MachO::HeaderMagic32:
226             case llvm::MachO::HeaderMagic64:
227             case llvm::MachO::HeaderMagic32Swapped:
228             case llvm::MachO::HeaderMagic64Swapped:
229                 return ReadDYLDInfoFromMemoryAndSetNotificationCallback(shlib_addr);
230 
231             default:
232                 break;
233             }
234         }
235         // Maybe it points to the all image infos?
236         m_dyld_all_image_infos_addr = shlib_addr;
237     }
238 
239     if (m_dyld_all_image_infos_addr != LLDB_INVALID_ADDRESS)
240     {
241         if (ReadAllImageInfosStructure ())
242         {
243             if (m_dyld_all_image_infos.dyldImageLoadAddress != LLDB_INVALID_ADDRESS)
244                 return ReadDYLDInfoFromMemoryAndSetNotificationCallback (m_dyld_all_image_infos.dyldImageLoadAddress);
245             else
246                 return ReadDYLDInfoFromMemoryAndSetNotificationCallback (m_dyld_all_image_infos_addr & 0xfffffffffff00000ull);
247         }
248     }
249 
250     // Check some default values
251     Module *executable = m_process->GetTarget().GetExecutableModulePointer();
252 
253     if (executable)
254     {
255         const ArchSpec &exe_arch = executable->GetArchitecture();
256         if (exe_arch.GetAddressByteSize() == 8)
257         {
258             return ReadDYLDInfoFromMemoryAndSetNotificationCallback(0x7fff5fc00000ull);
259         }
260         else if (exe_arch.GetMachine() == llvm::Triple::arm || exe_arch.GetMachine() == llvm::Triple::thumb)
261         {
262             return ReadDYLDInfoFromMemoryAndSetNotificationCallback(0x2fe00000);
263         }
264         else
265         {
266             return ReadDYLDInfoFromMemoryAndSetNotificationCallback(0x8fe00000);
267         }
268     }
269     return false;
270 }
271 
272 ModuleSP
273 DynamicLoaderMacOSXDYLD::FindTargetModuleForDYLDImageInfo (const DYLDImageInfo &image_info, bool can_create, bool *did_create_ptr)
274 {
275     if (did_create_ptr)
276         *did_create_ptr = false;
277     ModuleList &target_images = m_process->GetTarget().GetImages();
278     ModuleSpec module_spec (image_info.file_spec, image_info.GetArchitecture ());
279     module_spec.GetUUID() = image_info.uuid;
280     ModuleSP module_sp (target_images.FindFirstModule (module_spec));
281 
282     if (module_sp)
283     {
284         // No UUID, we must rely upon the cached module modification
285         // time and the modification time of the file on disk
286         if (module_sp->GetModificationTime() != module_sp->GetFileSpec().GetModificationTime())
287             module_sp.reset();
288     }
289 
290     if (!module_sp)
291     {
292         if (can_create)
293         {
294             if (!module_sp)
295             {
296                 module_sp = m_process->GetTarget().GetSharedModule (module_spec);
297                 if (!module_sp || module_sp->GetObjectFile() == NULL)
298                 {
299                     const bool add_image_to_target = true;
300                     const bool load_image_sections_in_target = false;
301                     module_sp = m_process->ReadModuleFromMemory (image_info.file_spec,
302                                                                  image_info.address,
303                                                                  add_image_to_target,
304                                                                  load_image_sections_in_target);
305                 }
306 
307                 if (did_create_ptr)
308                     *did_create_ptr = module_sp;
309             }
310         }
311     }
312     return module_sp;
313 }
314 
315 //----------------------------------------------------------------------
316 // Assume that dyld is in memory at ADDR and try to parse it's load
317 // commands
318 //----------------------------------------------------------------------
319 bool
320 DynamicLoaderMacOSXDYLD::ReadDYLDInfoFromMemoryAndSetNotificationCallback(lldb::addr_t addr)
321 {
322     DataExtractor data; // Load command data
323     if (ReadMachHeader (addr, &m_dyld.header, &data))
324     {
325         if (m_dyld.header.filetype == llvm::MachO::HeaderFileTypeDynamicLinkEditor)
326         {
327             m_dyld.address = addr;
328             ModuleSP dyld_module_sp;
329             if (ParseLoadCommands (data, m_dyld, &m_dyld.file_spec))
330             {
331                 if (m_dyld.file_spec)
332                 {
333                     dyld_module_sp = FindTargetModuleForDYLDImageInfo (m_dyld, true, NULL);
334 
335                     if (dyld_module_sp)
336                         UpdateImageLoadAddress (dyld_module_sp.get(), m_dyld);
337                 }
338             }
339 
340             if (m_dyld_all_image_infos_addr == LLDB_INVALID_ADDRESS && dyld_module_sp.get())
341             {
342                 static ConstString g_dyld_all_image_infos ("dyld_all_image_infos");
343                 const Symbol *symbol = dyld_module_sp->FindFirstSymbolWithNameAndType (g_dyld_all_image_infos, eSymbolTypeData);
344                 if (symbol)
345                     m_dyld_all_image_infos_addr = symbol->GetValue().GetLoadAddress(&m_process->GetTarget());
346             }
347 
348             // Update all image infos
349             InitializeFromAllImageInfos ();
350 
351             // If we didn't have an executable before, but now we do, then the
352             // dyld module shared pointer might be unique and we may need to add
353             // it again (since Target::SetExecutableModule() will clear the
354             // images). So append the dyld module back to the list if it is
355             /// unique!
356             if (dyld_module_sp && m_process->GetTarget().GetImages().AppendIfNeeded (dyld_module_sp))
357                 UpdateImageLoadAddress(dyld_module_sp.get(), m_dyld);
358 
359             return true;
360         }
361     }
362     return false;
363 }
364 
365 bool
366 DynamicLoaderMacOSXDYLD::NeedToLocateDYLD () const
367 {
368     return m_dyld_all_image_infos_addr == LLDB_INVALID_ADDRESS;
369 }
370 
371 bool
372 DynamicLoaderMacOSXDYLD::UpdateCommPageLoadAddress(Module *module)
373 {
374     bool changed = false;
375     if (module)
376     {
377         ObjectFile *image_object_file = module->GetObjectFile();
378         if (image_object_file)
379         {
380             SectionList *section_list = image_object_file->GetSectionList ();
381             if (section_list)
382             {
383                 uint32_t num_sections = section_list->GetSize();
384                 for (uint32_t i=0; i<num_sections; ++i)
385                 {
386                     Section* section = section_list->GetSectionAtIndex (i).get();
387                     if (section)
388                     {
389                         const addr_t new_section_load_addr = section->GetFileAddress ();
390                         const addr_t old_section_load_addr = m_process->GetTarget().GetSectionLoadList().GetSectionLoadAddress (section);
391                         if (old_section_load_addr == LLDB_INVALID_ADDRESS ||
392                             old_section_load_addr != new_section_load_addr)
393                         {
394                             if (m_process->GetTarget().GetSectionLoadList().SetSectionLoadAddress (section, section->GetFileAddress ()))
395                                 changed = true;
396                         }
397                     }
398                 }
399             }
400         }
401     }
402     return changed;
403 }
404 
405 //----------------------------------------------------------------------
406 // Update the load addresses for all segments in MODULE using the
407 // updated INFO that is passed in.
408 //----------------------------------------------------------------------
409 bool
410 DynamicLoaderMacOSXDYLD::UpdateImageLoadAddress (Module *module, DYLDImageInfo& info)
411 {
412     bool changed = false;
413     if (module)
414     {
415         ObjectFile *image_object_file = module->GetObjectFile();
416         if (image_object_file)
417         {
418             SectionList *section_list = image_object_file->GetSectionList ();
419             if (section_list)
420             {
421                 std::vector<uint32_t> inaccessible_segment_indexes;
422                 // We now know the slide amount, so go through all sections
423                 // and update the load addresses with the correct values.
424                 uint32_t num_segments = info.segments.size();
425                 for (uint32_t i=0; i<num_segments; ++i)
426                 {
427                     // Only load a segment if it has protections. Things like
428                     // __PAGEZERO don't have any protections, and they shouldn't
429                     // be slid
430                     SectionSP section_sp(section_list->FindSectionByName(info.segments[i].name));
431 
432                     if (info.segments[i].maxprot == 0)
433                     {
434                         inaccessible_segment_indexes.push_back(i);
435                     }
436                     else
437                     {
438                         const addr_t new_section_load_addr = info.segments[i].vmaddr + info.slide;
439                         static ConstString g_section_name_LINKEDIT ("__LINKEDIT");
440 
441                         if (section_sp)
442                         {
443                             // Don't ever load any __LINKEDIT sections since the ones in the shared
444                             // cached will be coalesced into a single section and we will get warnings
445                             // about multiple sections mapping to the same address.
446                             if (section_sp->GetName() != g_section_name_LINKEDIT)
447                             {
448                                 const addr_t old_section_load_addr = m_process->GetTarget().GetSectionLoadList().GetSectionLoadAddress (section_sp.get());
449                                 if (old_section_load_addr == LLDB_INVALID_ADDRESS ||
450                                     old_section_load_addr != new_section_load_addr)
451                                 {
452                                     if (m_process->GetTarget().GetSectionLoadList().SetSectionLoadAddress (section_sp.get(), new_section_load_addr))
453                                         changed = true;
454                                 }
455                             }
456                         }
457                         else
458                         {
459                             Host::SystemLog (Host::eSystemLogWarning,
460                                              "warning: unable to find and load segment named '%s' at 0x%llx in '%s/%s' in macosx dynamic loader plug-in.\n",
461                                              info.segments[i].name.AsCString("<invalid>"),
462                                              (uint64_t)new_section_load_addr,
463                                              image_object_file->GetFileSpec().GetDirectory().AsCString(),
464                                              image_object_file->GetFileSpec().GetFilename().AsCString());
465                         }
466                     }
467                 }
468 
469                 // If the loaded the file (it changed) and we have segments that
470                 // are not readable or writeable, add them to the invalid memory
471                 // region cache for the process. This will typically only be
472                 // the __PAGEZERO segment in the main executable. We might be able
473                 // to apply this more generally to more sections that have no
474                 // protections in the future, but for now we are going to just
475                 // do __PAGEZERO.
476                 if (changed && !inaccessible_segment_indexes.empty())
477                 {
478                     for (uint32_t i=0; i<inaccessible_segment_indexes.size(); ++i)
479                     {
480                         const uint32_t seg_idx = inaccessible_segment_indexes[i];
481                         SectionSP section_sp(section_list->FindSectionByName(info.segments[seg_idx].name));
482 
483                         if (section_sp)
484                         {
485                             static ConstString g_pagezero_section_name("__PAGEZERO");
486                             if (g_pagezero_section_name == section_sp->GetName())
487                             {
488                                 // __PAGEZERO never slides...
489                                 const lldb::addr_t vmaddr = info.segments[seg_idx].vmaddr;
490                                 const lldb::addr_t vmsize = info.segments[seg_idx].vmsize;
491                                 Process::LoadRange pagezero_range (vmaddr, vmsize);
492                                 m_process->AddInvalidMemoryRegion(pagezero_range);
493                             }
494                         }
495                     }
496                 }
497             }
498         }
499     }
500     return changed;
501 }
502 
503 //----------------------------------------------------------------------
504 // Update the load addresses for all segments in MODULE using the
505 // updated INFO that is passed in.
506 //----------------------------------------------------------------------
507 bool
508 DynamicLoaderMacOSXDYLD::UnloadImageLoadAddress (Module *module, DYLDImageInfo& info)
509 {
510     bool changed = false;
511     if (module)
512     {
513         ObjectFile *image_object_file = module->GetObjectFile();
514         if (image_object_file)
515         {
516             SectionList *section_list = image_object_file->GetSectionList ();
517             if (section_list)
518             {
519                 uint32_t num_segments = info.segments.size();
520                 for (uint32_t i=0; i<num_segments; ++i)
521                 {
522                     SectionSP section_sp(section_list->FindSectionByName(info.segments[i].name));
523                     if (section_sp)
524                     {
525                         const addr_t old_section_load_addr = info.segments[i].vmaddr + info.slide;
526                         if (m_process->GetTarget().GetSectionLoadList().SetSectionUnloaded (section_sp.get(), old_section_load_addr))
527                             changed = true;
528                     }
529                     else
530                     {
531                         Host::SystemLog (Host::eSystemLogWarning,
532                                          "warning: unable to find and unload segment named '%s' in '%s/%s' in macosx dynamic loader plug-in.\n",
533                                          info.segments[i].name.AsCString("<invalid>"),
534                                          image_object_file->GetFileSpec().GetDirectory().AsCString(),
535                                          image_object_file->GetFileSpec().GetFilename().AsCString());
536                     }
537                 }
538             }
539         }
540     }
541     return changed;
542 }
543 
544 
545 //----------------------------------------------------------------------
546 // Static callback function that gets called when our DYLD notification
547 // breakpoint gets hit. We update all of our image infos and then
548 // let our super class DynamicLoader class decide if we should stop
549 // or not (based on global preference).
550 //----------------------------------------------------------------------
551 bool
552 DynamicLoaderMacOSXDYLD::NotifyBreakpointHit (void *baton,
553                                               StoppointCallbackContext *context,
554                                               lldb::user_id_t break_id,
555                                               lldb::user_id_t break_loc_id)
556 {
557     // Let the event know that the images have changed
558     // DYLD passes three arguments to the notification breakpoint.
559     // Arg1: enum dyld_image_mode mode - 0 = adding, 1 = removing
560     // Arg2: uint32_t infoCount        - Number of shared libraries added
561     // Arg3: dyld_image_info info[]    - Array of structs of the form:
562     //                                     const struct mach_header *imageLoadAddress
563     //                                     const char               *imageFilePath
564     //                                     uintptr_t                 imageFileModDate (a time_t)
565 
566     DynamicLoaderMacOSXDYLD* dyld_instance = (DynamicLoaderMacOSXDYLD*) baton;
567 
568     // First step is to see if we've already initialized the all image infos.  If we haven't then this function
569     // will do so and return true.  In the course of initializing the all_image_infos it will read the complete
570     // current state, so we don't need to figure out what has changed from the data passed in to us.
571 
572     if (dyld_instance->InitializeFromAllImageInfos())
573         return dyld_instance->GetStopWhenImagesChange();
574 
575     ExecutionContext exe_ctx (context->exe_ctx_ref);
576     Process *process = exe_ctx.GetProcessPtr();
577     const lldb::ABISP &abi = process->GetABI();
578     if (abi != NULL)
579     {
580         // Build up the value array to store the three arguments given above, then get the values from the ABI:
581 
582         ClangASTContext *clang_ast_context = process->GetTarget().GetScratchClangASTContext();
583         ValueList argument_values;
584         Value input_value;
585 
586         void *clang_void_ptr_type = clang_ast_context->GetVoidPtrType(false);
587         void *clang_uint32_type   = clang_ast_context->GetBuiltinTypeForEncodingAndBitSize(lldb::eEncodingUint, 32);
588         input_value.SetValueType (Value::eValueTypeScalar);
589         input_value.SetContext (Value::eContextTypeClangType, clang_uint32_type);
590         argument_values.PushValue(input_value);
591         argument_values.PushValue(input_value);
592         input_value.SetContext (Value::eContextTypeClangType, clang_void_ptr_type);
593         argument_values.PushValue (input_value);
594 
595         if (abi->GetArgumentValues (exe_ctx.GetThreadRef(), argument_values))
596         {
597             uint32_t dyld_mode = argument_values.GetValueAtIndex(0)->GetScalar().UInt (-1);
598             if (dyld_mode != -1)
599             {
600                 // Okay the mode was right, now get the number of elements, and the array of new elements...
601                 uint32_t image_infos_count = argument_values.GetValueAtIndex(1)->GetScalar().UInt (-1);
602                 if (image_infos_count != -1)
603                 {
604                     // Got the number added, now go through the array of added elements, putting out the mach header
605                     // address, and adding the image.
606                     // Note, I'm not putting in logging here, since the AddModules & RemoveModules functions do
607                     // all the logging internally.
608 
609                     lldb::addr_t image_infos_addr = argument_values.GetValueAtIndex(2)->GetScalar().ULongLong();
610                     if (dyld_mode == 0)
611                     {
612                         // This is add:
613                         dyld_instance->AddModulesUsingImageInfosAddress (image_infos_addr, image_infos_count);
614                     }
615                     else
616                     {
617                         // This is remove:
618                         dyld_instance->RemoveModulesUsingImageInfosAddress (image_infos_addr, image_infos_count);
619                     }
620 
621                 }
622             }
623         }
624     }
625 
626     // Return true to stop the target, false to just let the target run
627     return dyld_instance->GetStopWhenImagesChange();
628 }
629 
630 bool
631 DynamicLoaderMacOSXDYLD::ReadAllImageInfosStructure ()
632 {
633     Mutex::Locker locker(m_mutex);
634 
635     // the all image infos is already valid for this process stop ID
636     if (m_process->GetStopID() == m_dyld_all_image_infos_stop_id)
637         return true;
638 
639     m_dyld_all_image_infos.Clear();
640     if (m_dyld_all_image_infos_addr != LLDB_INVALID_ADDRESS)
641     {
642         ByteOrder byte_order = m_process->GetTarget().GetArchitecture().GetByteOrder();
643         uint32_t addr_size = 4;
644         if (m_dyld_all_image_infos_addr > UINT32_MAX)
645             addr_size = 8;
646 
647         uint8_t buf[256];
648         DataExtractor data (buf, sizeof(buf), byte_order, addr_size);
649         uint32_t offset = 0;
650 
651         const size_t count_v2 =  sizeof (uint32_t) + // version
652                                  sizeof (uint32_t) + // infoArrayCount
653                                  addr_size +         // infoArray
654                                  addr_size +         // notification
655                                  addr_size +         // processDetachedFromSharedRegion + libSystemInitialized + pad
656                                  addr_size;          // dyldImageLoadAddress
657         const size_t count_v11 = count_v2 +
658                                  addr_size +         // jitInfo
659                                  addr_size +         // dyldVersion
660                                  addr_size +         // errorMessage
661                                  addr_size +         // terminationFlags
662                                  addr_size +         // coreSymbolicationShmPage
663                                  addr_size +         // systemOrderFlag
664                                  addr_size +         // uuidArrayCount
665                                  addr_size +         // uuidArray
666                                  addr_size +         // dyldAllImageInfosAddress
667                                  addr_size +         // initialImageCount
668                                  addr_size +         // errorKind
669                                  addr_size +         // errorClientOfDylibPath
670                                  addr_size +         // errorTargetDylibPath
671                                  addr_size;          // errorSymbol
672         assert (sizeof (buf) >= count_v11);
673 
674         int count;
675         Error error;
676         if (m_process->ReadMemory (m_dyld_all_image_infos_addr, buf, 4, error) == 4)
677         {
678             m_dyld_all_image_infos.version = data.GetU32(&offset);
679             // If anything in the high byte is set, we probably got the byte
680             // order incorrect (the process might not have it set correctly
681             // yet due to attaching to a program without a specified file).
682             if (m_dyld_all_image_infos.version & 0xff000000)
683             {
684                 // We have guessed the wrong byte order. Swap it and try
685                 // reading the version again.
686                 if (byte_order == eByteOrderLittle)
687                     byte_order = eByteOrderBig;
688                 else
689                     byte_order = eByteOrderLittle;
690 
691                 data.SetByteOrder (byte_order);
692                 offset = 0;
693                 m_dyld_all_image_infos.version = data.GetU32(&offset);
694             }
695         }
696         else
697         {
698             return false;
699         }
700 
701         if (m_dyld_all_image_infos.version >= 11)
702             count = count_v11;
703         else
704             count = count_v2;
705 
706         const size_t bytes_read = m_process->ReadMemory (m_dyld_all_image_infos_addr, buf, count, error);
707         if (bytes_read == count)
708         {
709             offset = 0;
710             m_dyld_all_image_infos.version = data.GetU32(&offset);
711             m_dyld_all_image_infos.dylib_info_count = data.GetU32(&offset);
712             m_dyld_all_image_infos.dylib_info_addr = data.GetPointer(&offset);
713             m_dyld_all_image_infos.notification = data.GetPointer(&offset);
714             m_dyld_all_image_infos.processDetachedFromSharedRegion = data.GetU8(&offset);
715             m_dyld_all_image_infos.libSystemInitialized = data.GetU8(&offset);
716             // Adjust for padding.
717             offset += addr_size - 2;
718             m_dyld_all_image_infos.dyldImageLoadAddress = data.GetPointer(&offset);
719             if (m_dyld_all_image_infos.version >= 11)
720             {
721                 offset += addr_size * 8;
722                 uint64_t dyld_all_image_infos_addr = data.GetPointer(&offset);
723 
724                 // When we started, we were given the actual address of the all_image_infos
725                 // struct (probably via TASK_DYLD_INFO) in memory - this address is stored in
726                 // m_dyld_all_image_infos_addr and is the most accurate address we have.
727 
728                 // We read the dyld_all_image_infos struct from memory; it contains its own address.
729                 // If the address in the struct does not match the actual address,
730                 // the dyld we're looking at has been loaded at a different location (slid) from
731                 // where it intended to load.  The addresses in the dyld_all_image_infos struct
732                 // are the original, non-slid addresses, and need to be adjusted.  Most importantly
733                 // the address of dyld and the notification address need to be adjusted.
734 
735                 if (dyld_all_image_infos_addr != m_dyld_all_image_infos_addr)
736                 {
737                     uint64_t image_infos_offset = dyld_all_image_infos_addr - m_dyld_all_image_infos.dyldImageLoadAddress;
738                     uint64_t notification_offset = m_dyld_all_image_infos.notification - m_dyld_all_image_infos.dyldImageLoadAddress;
739                     m_dyld_all_image_infos.dyldImageLoadAddress = m_dyld_all_image_infos_addr - image_infos_offset;
740                     m_dyld_all_image_infos.notification = m_dyld_all_image_infos.dyldImageLoadAddress + notification_offset;
741                 }
742             }
743             m_dyld_all_image_infos_stop_id = m_process->GetStopID();
744             return true;
745         }
746     }
747     return false;
748 }
749 
750 
751 bool
752 DynamicLoaderMacOSXDYLD::AddModulesUsingImageInfosAddress (lldb::addr_t image_infos_addr, uint32_t image_infos_count)
753 {
754     DYLDImageInfo::collection image_infos;
755     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
756     if (log)
757         log->Printf ("Adding %d modules.\n", image_infos_count);
758 
759     Mutex::Locker locker(m_mutex);
760     if (m_process->GetStopID() == m_dyld_image_infos_stop_id)
761         return true;
762 
763     if (!ReadImageInfos (image_infos_addr, image_infos_count, image_infos))
764         return false;
765 
766     UpdateImageInfosHeaderAndLoadCommands (image_infos, image_infos_count, false);
767     bool return_value = AddModulesUsingImageInfos (image_infos);
768     m_dyld_image_infos_stop_id = m_process->GetStopID();
769     return return_value;
770 }
771 
772 // Adds the modules in image_infos to m_dyld_image_infos.
773 // NB don't call this passing in m_dyld_image_infos.
774 
775 bool
776 DynamicLoaderMacOSXDYLD::AddModulesUsingImageInfos (DYLDImageInfo::collection &image_infos)
777 {
778     // Now add these images to the main list.
779     ModuleList loaded_module_list;
780     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
781 
782     for (uint32_t idx = 0; idx < image_infos.size(); ++idx)
783     {
784         if (log)
785         {
786             log->Printf ("Adding new image at address=0x%16.16llx.", image_infos[idx].address);
787             image_infos[idx].PutToLog (log.get());
788         }
789 
790         m_dyld_image_infos.push_back(image_infos[idx]);
791 
792         ModuleSP image_module_sp (FindTargetModuleForDYLDImageInfo (image_infos[idx], true, NULL));
793 
794         if (image_module_sp)
795         {
796             if (image_infos[idx].header.filetype == llvm::MachO::HeaderFileTypeDynamicLinkEditor)
797                 image_module_sp->SetIsDynamicLinkEditor (true);
798 
799             ObjectFile *objfile = image_module_sp->GetObjectFile ();
800             if (objfile)
801             {
802                 SectionList *sections = objfile->GetSectionList();
803                 if (sections)
804                 {
805                     ConstString commpage_dbstr("__commpage");
806                     Section *commpage_section = sections->FindSectionByName(commpage_dbstr).get();
807                     if (commpage_section)
808                     {
809                         ModuleList& target_images = m_process->GetTarget().GetImages();
810                         ModuleSpec module_spec (objfile->GetFileSpec(), image_infos[idx].GetArchitecture ());
811                         module_spec.GetObjectName() = commpage_dbstr;
812                         ModuleSP commpage_image_module_sp(target_images.FindFirstModule (module_spec));
813                         if (!commpage_image_module_sp)
814                         {
815                             module_spec.SetObjectOffset (objfile->GetOffset() + commpage_section->GetFileOffset());
816                             commpage_image_module_sp  = m_process->GetTarget().GetSharedModule (module_spec);
817                             if (!commpage_image_module_sp || commpage_image_module_sp->GetObjectFile() == NULL)
818                             {
819                                 const bool add_image_to_target = true;
820                                 const bool load_image_sections_in_target = false;
821                                 commpage_image_module_sp = m_process->ReadModuleFromMemory (image_infos[idx].file_spec,
822                                                                                             image_infos[idx].address,
823                                                                                             add_image_to_target,
824                                                                                             load_image_sections_in_target);
825                             }
826                         }
827                         if (commpage_image_module_sp)
828                             UpdateCommPageLoadAddress (commpage_image_module_sp.get());
829                     }
830                 }
831             }
832 
833             // UpdateImageLoadAddress will return true if any segments
834             // change load address. We need to check this so we don't
835             // mention that all loaded shared libraries are newly loaded
836             // each time we hit out dyld breakpoint since dyld will list all
837             // shared libraries each time.
838             if (UpdateImageLoadAddress (image_module_sp.get(), image_infos[idx]))
839             {
840                 loaded_module_list.AppendIfNeeded (image_module_sp);
841             }
842         }
843     }
844 
845     if (loaded_module_list.GetSize() > 0)
846     {
847         // FIXME: This should really be in the Runtime handlers class, which should get
848         // called by the target's ModulesDidLoad, but we're doing it all locally for now
849         // to save time.
850         // Also, I'm assuming there can be only one libobjc dylib loaded...
851 
852         ObjCLanguageRuntime *objc_runtime = m_process->GetObjCLanguageRuntime();
853         if (objc_runtime != NULL && !objc_runtime->HasReadObjCLibrary())
854         {
855             size_t num_modules = loaded_module_list.GetSize();
856             for (int i = 0; i < num_modules; i++)
857             {
858                 if (objc_runtime->IsModuleObjCLibrary (loaded_module_list.GetModuleAtIndex (i)))
859                 {
860                     objc_runtime->ReadObjCLibrary (loaded_module_list.GetModuleAtIndex (i));
861                     break;
862                 }
863             }
864         }
865         if (log)
866             loaded_module_list.LogUUIDAndPaths (log, "DynamicLoaderMacOSXDYLD::ModulesDidLoad");
867         m_process->GetTarget().ModulesDidLoad (loaded_module_list);
868     }
869     return true;
870 }
871 
872 bool
873 DynamicLoaderMacOSXDYLD::RemoveModulesUsingImageInfosAddress (lldb::addr_t image_infos_addr, uint32_t image_infos_count)
874 {
875     DYLDImageInfo::collection image_infos;
876     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
877 
878     Mutex::Locker locker(m_mutex);
879     if (m_process->GetStopID() == m_dyld_image_infos_stop_id)
880         return true;
881 
882     // First read in the image_infos for the removed modules, and their headers & load commands.
883     if (!ReadImageInfos (image_infos_addr, image_infos_count, image_infos))
884     {
885         if (log)
886             log->PutCString ("Failed reading image infos array.");
887         return false;
888     }
889 
890     if (log)
891         log->Printf ("Removing %d modules.", image_infos_count);
892 
893     ModuleList unloaded_module_list;
894     for (uint32_t idx = 0; idx < image_infos.size(); ++idx)
895     {
896         if (log)
897         {
898             log->Printf ("Removing module at address=0x%16.16llx.", image_infos[idx].address);
899             image_infos[idx].PutToLog (log.get());
900         }
901 
902         // Remove this image_infos from the m_all_image_infos.  We do the comparision by address
903         // rather than by file spec because we can have many modules with the same "file spec" in the
904         // case that they are modules loaded from memory.
905         //
906         // Also copy over the uuid from the old entry to the removed entry so we can
907         // use it to lookup the module in the module list.
908 
909         DYLDImageInfo::collection::iterator pos, end = m_dyld_image_infos.end();
910         for (pos = m_dyld_image_infos.begin(); pos != end; pos++)
911         {
912             if (image_infos[idx].address == (*pos).address)
913             {
914                 image_infos[idx].uuid = (*pos).uuid;
915 
916                 // Add the module from this image_info to the "unloaded_module_list".  We'll remove them all at
917                 // one go later on.
918 
919                 ModuleSP unload_image_module_sp (FindTargetModuleForDYLDImageInfo (image_infos[idx], false, NULL));
920                 if (unload_image_module_sp.get())
921                 {
922                     // When we unload, be sure to use the image info from the old list,
923                     // since that has sections correctly filled in.
924                     UnloadImageLoadAddress (unload_image_module_sp.get(), *pos);
925                     unloaded_module_list.AppendIfNeeded (unload_image_module_sp);
926                 }
927                 else
928                 {
929                     if (log)
930                     {
931                         log->Printf ("Could not find module for unloading info entry:");
932                         image_infos[idx].PutToLog(log.get());
933                     }
934                 }
935 
936                 // Then remove it from the m_dyld_image_infos:
937 
938                 m_dyld_image_infos.erase(pos);
939                 break;
940             }
941         }
942 
943         if (pos == end)
944         {
945             if (log)
946             {
947                 log->Printf ("Could not find image_info entry for unloading image:");
948                 image_infos[idx].PutToLog(log.get());
949             }
950         }
951     }
952     if (unloaded_module_list.GetSize() > 0)
953     {
954         if (log)
955         {
956             log->PutCString("Unloaded:");
957             unloaded_module_list.LogUUIDAndPaths (log, "DynamicLoaderMacOSXDYLD::ModulesDidUnload");
958         }
959         m_process->GetTarget().ModulesDidUnload (unloaded_module_list);
960     }
961     m_dyld_image_infos_stop_id = m_process->GetStopID();
962     return true;
963 }
964 
965 bool
966 DynamicLoaderMacOSXDYLD::ReadImageInfos (lldb::addr_t image_infos_addr,
967                                          uint32_t image_infos_count,
968                                          DYLDImageInfo::collection &image_infos)
969 {
970     const ByteOrder endian = m_dyld.GetByteOrder();
971     const uint32_t addr_size = m_dyld.GetAddressByteSize();
972 
973     image_infos.resize(image_infos_count);
974     const size_t count = image_infos.size() * 3 * addr_size;
975     DataBufferHeap info_data(count, 0);
976     Error error;
977     const size_t bytes_read = m_process->ReadMemory (image_infos_addr,
978                                                      info_data.GetBytes(),
979                                                      info_data.GetByteSize(),
980                                                      error);
981     if (bytes_read == count)
982     {
983         uint32_t info_data_offset = 0;
984         DataExtractor info_data_ref(info_data.GetBytes(), info_data.GetByteSize(), endian, addr_size);
985         for (int i = 0; i < image_infos.size() && info_data_ref.ValidOffset(info_data_offset); i++)
986         {
987             image_infos[i].address = info_data_ref.GetPointer(&info_data_offset);
988             lldb::addr_t path_addr = info_data_ref.GetPointer(&info_data_offset);
989             image_infos[i].mod_date = info_data_ref.GetPointer(&info_data_offset);
990 
991             char raw_path[PATH_MAX];
992             m_process->ReadCStringFromMemory (path_addr, raw_path, sizeof(raw_path), error);
993             // don't resolve the path
994             if (error.Success())
995             {
996                 const bool resolve_path = false;
997                 image_infos[i].file_spec.SetFile(raw_path, resolve_path);
998             }
999         }
1000         return true;
1001     }
1002     else
1003     {
1004         return false;
1005     }
1006 }
1007 
1008 //----------------------------------------------------------------------
1009 // If we have found where the "_dyld_all_image_infos" lives in memory,
1010 // read the current info from it, and then update all image load
1011 // addresses (or lack thereof).  Only do this if this is the first time
1012 // we're reading the dyld infos.  Return true if we actually read anything,
1013 // and false otherwise.
1014 //----------------------------------------------------------------------
1015 bool
1016 DynamicLoaderMacOSXDYLD::InitializeFromAllImageInfos ()
1017 {
1018     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1019 
1020     Mutex::Locker locker(m_mutex);
1021     if (m_process->GetStopID() == m_dyld_image_infos_stop_id
1022           || m_dyld_image_infos.size() != 0)
1023         return false;
1024 
1025     if (ReadAllImageInfosStructure ())
1026     {
1027         // Nothing to load or unload?
1028         if (m_dyld_all_image_infos.dylib_info_count == 0)
1029             return true;
1030 
1031         if (m_dyld_all_image_infos.dylib_info_addr == 0)
1032         {
1033             // DYLD is updating the images now.  So we should say we have no images, and then we'll
1034             // figure it out when we hit the added breakpoint.
1035             return false;
1036         }
1037         else
1038         {
1039             if (!AddModulesUsingImageInfosAddress (m_dyld_all_image_infos.dylib_info_addr,
1040                                                    m_dyld_all_image_infos.dylib_info_count))
1041             {
1042                 DEBUG_PRINTF( "unable to read all data for all_dylib_infos.");
1043                 m_dyld_image_infos.clear();
1044             }
1045         }
1046 
1047         // Now we have one more bit of business.  If there is a library left in the images for our target that
1048         // doesn't have a load address, then it must be something that we were expecting to load (for instance we
1049         // read a load command for it) but it didn't in fact load - probably because DYLD_*_PATH pointed
1050         // to an equivalent version.  We don't want it to stay in the target's module list or it will confuse
1051         // us, so unload it here.
1052         Target &target = m_process->GetTarget();
1053         ModuleList &modules = target.GetImages();
1054         ModuleList not_loaded_modules;
1055         size_t num_modules = modules.GetSize();
1056         for (size_t i = 0; i < num_modules; i++)
1057         {
1058             ModuleSP module_sp = modules.GetModuleAtIndex(i);
1059             if (!module_sp->IsLoadedInTarget (&target))
1060             {
1061                 if (log)
1062                 {
1063                     StreamString s;
1064                     module_sp->GetDescription (&s);
1065                     log->Printf ("Unloading pre-run module: %s.", s.GetData ());
1066                 }
1067                 not_loaded_modules.Append (module_sp);
1068             }
1069         }
1070 
1071         if (not_loaded_modules.GetSize() != 0)
1072         {
1073             target.ModulesDidUnload(not_loaded_modules);
1074         }
1075 
1076         return true;
1077     }
1078     else
1079         return false;
1080 }
1081 
1082 //----------------------------------------------------------------------
1083 // Read a mach_header at ADDR into HEADER, and also fill in the load
1084 // command data into LOAD_COMMAND_DATA if it is non-NULL.
1085 //
1086 // Returns true if we succeed, false if we fail for any reason.
1087 //----------------------------------------------------------------------
1088 bool
1089 DynamicLoaderMacOSXDYLD::ReadMachHeader (lldb::addr_t addr, llvm::MachO::mach_header *header, DataExtractor *load_command_data)
1090 {
1091     DataBufferHeap header_bytes(sizeof(llvm::MachO::mach_header), 0);
1092     Error error;
1093     size_t bytes_read = m_process->ReadMemory (addr,
1094                                                header_bytes.GetBytes(),
1095                                                header_bytes.GetByteSize(),
1096                                                error);
1097     if (bytes_read == sizeof(llvm::MachO::mach_header))
1098     {
1099         uint32_t offset = 0;
1100         ::memset (header, 0, sizeof(llvm::MachO::mach_header));
1101 
1102         // Get the magic byte unswapped so we can figure out what we are dealing with
1103         DataExtractor data(header_bytes.GetBytes(), header_bytes.GetByteSize(), lldb::endian::InlHostByteOrder(), 4);
1104         header->magic = data.GetU32(&offset);
1105         lldb::addr_t load_cmd_addr = addr;
1106         data.SetByteOrder(DynamicLoaderMacOSXDYLD::GetByteOrderFromMagic(header->magic));
1107         switch (header->magic)
1108         {
1109         case llvm::MachO::HeaderMagic32:
1110         case llvm::MachO::HeaderMagic32Swapped:
1111             data.SetAddressByteSize(4);
1112             load_cmd_addr += sizeof(llvm::MachO::mach_header);
1113             break;
1114 
1115         case llvm::MachO::HeaderMagic64:
1116         case llvm::MachO::HeaderMagic64Swapped:
1117             data.SetAddressByteSize(8);
1118             load_cmd_addr += sizeof(llvm::MachO::mach_header_64);
1119             break;
1120 
1121         default:
1122             return false;
1123         }
1124 
1125         // Read the rest of dyld's mach header
1126         if (data.GetU32(&offset, &header->cputype, (sizeof(llvm::MachO::mach_header)/sizeof(uint32_t)) - 1))
1127         {
1128             if (load_command_data == NULL)
1129                 return true; // We were able to read the mach_header and weren't asked to read the load command bytes
1130 
1131             DataBufferSP load_cmd_data_sp(new DataBufferHeap(header->sizeofcmds, 0));
1132 
1133             size_t load_cmd_bytes_read = m_process->ReadMemory (load_cmd_addr,
1134                                                                 load_cmd_data_sp->GetBytes(),
1135                                                                 load_cmd_data_sp->GetByteSize(),
1136                                                                 error);
1137 
1138             if (load_cmd_bytes_read == header->sizeofcmds)
1139             {
1140                 // Set the load command data and also set the correct endian
1141                 // swap settings and the correct address size
1142                 load_command_data->SetData(load_cmd_data_sp, 0, header->sizeofcmds);
1143                 load_command_data->SetByteOrder(data.GetByteOrder());
1144                 load_command_data->SetAddressByteSize(data.GetAddressByteSize());
1145                 return true; // We successfully read the mach_header and the load command data
1146             }
1147 
1148             return false; // We weren't able to read the load command data
1149         }
1150     }
1151     return false; // We failed the read the mach_header
1152 }
1153 
1154 
1155 //----------------------------------------------------------------------
1156 // Parse the load commands for an image
1157 //----------------------------------------------------------------------
1158 uint32_t
1159 DynamicLoaderMacOSXDYLD::ParseLoadCommands (const DataExtractor& data, DYLDImageInfo& dylib_info, FileSpec *lc_id_dylinker)
1160 {
1161     uint32_t offset = 0;
1162     uint32_t cmd_idx;
1163     Segment segment;
1164     dylib_info.Clear (true);
1165 
1166     for (cmd_idx = 0; cmd_idx < dylib_info.header.ncmds; cmd_idx++)
1167     {
1168         // Clear out any load command specific data from DYLIB_INFO since
1169         // we are about to read it.
1170 
1171         if (data.ValidOffsetForDataOfSize (offset, sizeof(llvm::MachO::load_command)))
1172         {
1173             llvm::MachO::load_command load_cmd;
1174             uint32_t load_cmd_offset = offset;
1175             load_cmd.cmd = data.GetU32 (&offset);
1176             load_cmd.cmdsize = data.GetU32 (&offset);
1177             switch (load_cmd.cmd)
1178             {
1179             case llvm::MachO::LoadCommandSegment32:
1180                 {
1181                     segment.name.SetTrimmedCStringWithLength ((const char *)data.GetData(&offset, 16), 16);
1182                     // We are putting 4 uint32_t values 4 uint64_t values so
1183                     // we have to use multiple 32 bit gets below.
1184                     segment.vmaddr = data.GetU32 (&offset);
1185                     segment.vmsize = data.GetU32 (&offset);
1186                     segment.fileoff = data.GetU32 (&offset);
1187                     segment.filesize = data.GetU32 (&offset);
1188                     // Extract maxprot, initprot, nsects and flags all at once
1189                     data.GetU32(&offset, &segment.maxprot, 4);
1190                     dylib_info.segments.push_back (segment);
1191                 }
1192                 break;
1193 
1194             case llvm::MachO::LoadCommandSegment64:
1195                 {
1196                     segment.name.SetTrimmedCStringWithLength ((const char *)data.GetData(&offset, 16), 16);
1197                     // Extract vmaddr, vmsize, fileoff, and filesize all at once
1198                     data.GetU64(&offset, &segment.vmaddr, 4);
1199                     // Extract maxprot, initprot, nsects and flags all at once
1200                     data.GetU32(&offset, &segment.maxprot, 4);
1201                     dylib_info.segments.push_back (segment);
1202                 }
1203                 break;
1204 
1205             case llvm::MachO::LoadCommandDynamicLinkerIdent:
1206                 if (lc_id_dylinker)
1207                 {
1208                     uint32_t name_offset = load_cmd_offset + data.GetU32 (&offset);
1209                     const char *path = data.PeekCStr (name_offset);
1210                     lc_id_dylinker->SetFile (path, true);
1211                 }
1212                 break;
1213 
1214             case llvm::MachO::LoadCommandUUID:
1215                 dylib_info.uuid.SetBytes(data.GetData (&offset, 16));
1216                 break;
1217 
1218             default:
1219                 break;
1220             }
1221             // Set offset to be the beginning of the next load command.
1222             offset = load_cmd_offset + load_cmd.cmdsize;
1223         }
1224     }
1225 
1226     // All sections listed in the dyld image info structure will all
1227     // either be fixed up already, or they will all be off by a single
1228     // slide amount that is determined by finding the first segment
1229     // that is at file offset zero which also has bytes (a file size
1230     // that is greater than zero) in the object file.
1231 
1232     // Determine the slide amount (if any)
1233     const size_t num_sections = dylib_info.segments.size();
1234     for (size_t i = 0; i < num_sections; ++i)
1235     {
1236         // Iterate through the object file sections to find the
1237         // first section that starts of file offset zero and that
1238         // has bytes in the file...
1239         if (dylib_info.segments[i].fileoff == 0 && dylib_info.segments[i].filesize > 0)
1240         {
1241             dylib_info.slide = dylib_info.address - dylib_info.segments[i].vmaddr;
1242             // We have found the slide amount, so we can exit
1243             // this for loop.
1244             break;
1245         }
1246     }
1247     return cmd_idx;
1248 }
1249 
1250 //----------------------------------------------------------------------
1251 // Read the mach_header and load commands for each image that the
1252 // _dyld_all_image_infos structure points to and cache the results.
1253 //----------------------------------------------------------------------
1254 
1255 void
1256 DynamicLoaderMacOSXDYLD::UpdateImageInfosHeaderAndLoadCommands(DYLDImageInfo::collection &image_infos,
1257                                                                uint32_t infos_count,
1258                                                                bool update_executable)
1259 {
1260     uint32_t exe_idx = UINT32_MAX;
1261     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1262     // Read any UUID values that we can get
1263     for (uint32_t i = 0; i < infos_count; i++)
1264     {
1265         if (!image_infos[i].UUIDValid())
1266         {
1267             DataExtractor data; // Load command data
1268             if (!ReadMachHeader (image_infos[i].address, &image_infos[i].header, &data))
1269                 continue;
1270 
1271             ParseLoadCommands (data, image_infos[i], NULL);
1272 
1273             if (image_infos[i].header.filetype == llvm::MachO::HeaderFileTypeExecutable)
1274                 exe_idx = i;
1275 
1276         }
1277     }
1278 
1279     if (exe_idx < image_infos.size())
1280     {
1281         const bool can_create = true;
1282         ModuleSP exe_module_sp (FindTargetModuleForDYLDImageInfo (image_infos[exe_idx], can_create, NULL));
1283 
1284         if (!exe_module_sp)
1285         {
1286             ArchSpec exe_arch_spec (image_infos[exe_idx].GetArchitecture ());
1287             ModuleSpec module_spec (image_infos[exe_idx].file_spec,
1288                                     image_infos[exe_idx].GetArchitecture ());
1289             module_spec.GetUUID() = image_infos[exe_idx].uuid;
1290             exe_module_sp = m_process->GetTarget().GetSharedModule (module_spec);
1291             if (!exe_module_sp || exe_module_sp->GetObjectFile() == NULL)
1292             {
1293                 const bool add_image_to_target = true;
1294                 const bool load_image_sections_in_target = false;
1295                 exe_module_sp = m_process->ReadModuleFromMemory (image_infos[exe_idx].file_spec,
1296                                                                  image_infos[exe_idx].address,
1297                                                                  add_image_to_target,
1298                                                                  load_image_sections_in_target);
1299             }
1300         }
1301 
1302         if (exe_module_sp)
1303         {
1304             if (exe_module_sp.get() != m_process->GetTarget().GetExecutableModulePointer())
1305             {
1306                 // Don't load dependent images since we are in dyld where we will know
1307                 // and find out about all images that are loaded
1308                 const bool get_dependent_images = false;
1309                 m_process->GetTarget().SetExecutableModule (exe_module_sp,
1310                                                             get_dependent_images);
1311             }
1312         }
1313     }
1314 }
1315 
1316 //----------------------------------------------------------------------
1317 // On Mac OS X libobjc (the Objective-C runtime) has several critical dispatch
1318 // functions written in hand-written assembly, and also have hand-written unwind
1319 // information in the eh_frame section.  Normally we prefer analyzing the
1320 // assembly instructions of a curently executing frame to unwind from that frame --
1321 // but on hand-written functions this profiling can fail.  We should use the
1322 // eh_frame instructions for these functions all the time.
1323 //
1324 // As an aside, it would be better if the eh_frame entries had a flag (or were
1325 // extensible so they could have an Apple-specific flag) which indicates that
1326 // the instructions are asynchronous -- accurate at every instruction, instead
1327 // of our normal default assumption that they are not.
1328 //----------------------------------------------------------------------
1329 
1330 bool
1331 DynamicLoaderMacOSXDYLD::AlwaysRelyOnEHUnwindInfo (SymbolContext &sym_ctx)
1332 {
1333     ModuleSP module_sp;
1334     if (sym_ctx.symbol)
1335     {
1336         AddressRange *ar = sym_ctx.symbol->GetAddressRangePtr();
1337         if (ar)
1338         {
1339             module_sp = ar->GetBaseAddress().GetModule();
1340         }
1341     }
1342     if (module_sp.get() == NULL && sym_ctx.function)
1343     {
1344         module_sp = sym_ctx.function->GetAddressRange().GetBaseAddress().GetModule();
1345     }
1346     if (module_sp.get() == NULL)
1347         return false;
1348 
1349     ObjCLanguageRuntime *objc_runtime = m_process->GetObjCLanguageRuntime();
1350     if (objc_runtime != NULL && objc_runtime->IsModuleObjCLibrary (module_sp))
1351     {
1352         return true;
1353     }
1354 
1355     return false;
1356 }
1357 
1358 
1359 
1360 //----------------------------------------------------------------------
1361 // Dump a Segment to the file handle provided.
1362 //----------------------------------------------------------------------
1363 void
1364 DynamicLoaderMacOSXDYLD::Segment::PutToLog (Log *log, lldb::addr_t slide) const
1365 {
1366     if (log)
1367     {
1368         if (slide == 0)
1369             log->Printf ("\t\t%16s [0x%16.16llx - 0x%16.16llx)",
1370                          name.AsCString(""),
1371                          vmaddr + slide,
1372                          vmaddr + slide + vmsize);
1373         else
1374             log->Printf ("\t\t%16s [0x%16.16llx - 0x%16.16llx) slide = 0x%llx",
1375                          name.AsCString(""),
1376                          vmaddr + slide,
1377                          vmaddr + slide + vmsize,
1378                          slide);
1379     }
1380 }
1381 
1382 const DynamicLoaderMacOSXDYLD::Segment *
1383 DynamicLoaderMacOSXDYLD::DYLDImageInfo::FindSegment (const ConstString &name) const
1384 {
1385     const size_t num_segments = segments.size();
1386     for (size_t i=0; i<num_segments; ++i)
1387     {
1388         if (segments[i].name == name)
1389             return &segments[i];
1390     }
1391     return NULL;
1392 }
1393 
1394 
1395 //----------------------------------------------------------------------
1396 // Dump an image info structure to the file handle provided.
1397 //----------------------------------------------------------------------
1398 void
1399 DynamicLoaderMacOSXDYLD::DYLDImageInfo::PutToLog (Log *log) const
1400 {
1401     if (log == NULL)
1402         return;
1403     uint8_t *u = (uint8_t *)uuid.GetBytes();
1404 
1405     if (address == LLDB_INVALID_ADDRESS)
1406     {
1407         if (u)
1408         {
1409             log->Printf("\t                           modtime=0x%8.8llx uuid=%2.2X%2.2X%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X%2.2X%2.2X%2.2X%2.2X path='%s/%s' (UNLOADED)",
1410                         mod_date,
1411                         u[ 0], u[ 1], u[ 2], u[ 3],
1412                         u[ 4], u[ 5], u[ 6], u[ 7],
1413                         u[ 8], u[ 9], u[10], u[11],
1414                         u[12], u[13], u[14], u[15],
1415                         file_spec.GetDirectory().AsCString(),
1416                         file_spec.GetFilename().AsCString());
1417         }
1418         else
1419             log->Printf("\t                           modtime=0x%8.8llx path='%s/%s' (UNLOADED)",
1420                         mod_date,
1421                         file_spec.GetDirectory().AsCString(),
1422                         file_spec.GetFilename().AsCString());
1423     }
1424     else
1425     {
1426         if (u)
1427         {
1428             log->Printf("\taddress=0x%16.16llx modtime=0x%8.8llx uuid=%2.2X%2.2X%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X%2.2X%2.2X%2.2X%2.2X path='%s/%s'",
1429                         address,
1430                         mod_date,
1431                         u[ 0], u[ 1], u[ 2], u[ 3],
1432                         u[ 4], u[ 5], u[ 6], u[ 7],
1433                         u[ 8], u[ 9], u[10], u[11],
1434                         u[12], u[13], u[14], u[15],
1435                         file_spec.GetDirectory().AsCString(),
1436                         file_spec.GetFilename().AsCString());
1437         }
1438         else
1439         {
1440             log->Printf("\taddress=0x%16.16llx modtime=0x%8.8llx path='%s/%s'",
1441                         address,
1442                         mod_date,
1443                         file_spec.GetDirectory().AsCString(),
1444                         file_spec.GetFilename().AsCString());
1445 
1446         }
1447         for (uint32_t i=0; i<segments.size(); ++i)
1448             segments[i].PutToLog(log, slide);
1449     }
1450 }
1451 
1452 //----------------------------------------------------------------------
1453 // Dump the _dyld_all_image_infos members and all current image infos
1454 // that we have parsed to the file handle provided.
1455 //----------------------------------------------------------------------
1456 void
1457 DynamicLoaderMacOSXDYLD::PutToLog(Log *log) const
1458 {
1459     if (log == NULL)
1460         return;
1461 
1462     Mutex::Locker locker(m_mutex);
1463     log->Printf("dyld_all_image_infos = { version=%d, count=%d, addr=0x%8.8llx, notify=0x%8.8llx }",
1464                     m_dyld_all_image_infos.version,
1465                     m_dyld_all_image_infos.dylib_info_count,
1466                     (uint64_t)m_dyld_all_image_infos.dylib_info_addr,
1467                     (uint64_t)m_dyld_all_image_infos.notification);
1468     size_t i;
1469     const size_t count = m_dyld_image_infos.size();
1470     if (count > 0)
1471     {
1472         log->PutCString("Loaded:");
1473         for (i = 0; i<count; i++)
1474             m_dyld_image_infos[i].PutToLog(log);
1475     }
1476 }
1477 
1478 void
1479 DynamicLoaderMacOSXDYLD::PrivateInitialize(Process *process)
1480 {
1481     DEBUG_PRINTF("DynamicLoaderMacOSXDYLD::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1482     Clear(true);
1483     m_process = process;
1484     m_process->GetTarget().GetSectionLoadList().Clear();
1485 }
1486 
1487 bool
1488 DynamicLoaderMacOSXDYLD::SetNotificationBreakpoint ()
1489 {
1490     DEBUG_PRINTF("DynamicLoaderMacOSXDYLD::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1491     if (m_break_id == LLDB_INVALID_BREAK_ID)
1492     {
1493         if (m_dyld_all_image_infos.notification != LLDB_INVALID_ADDRESS)
1494         {
1495             Address so_addr;
1496             // Set the notification breakpoint and install a breakpoint
1497             // callback function that will get called each time the
1498             // breakpoint gets hit. We will use this to track when shared
1499             // libraries get loaded/unloaded.
1500 
1501             if (m_process->GetTarget().GetSectionLoadList().ResolveLoadAddress(m_dyld_all_image_infos.notification, so_addr))
1502             {
1503                 Breakpoint *dyld_break = m_process->GetTarget().CreateBreakpoint (so_addr, true).get();
1504                 dyld_break->SetCallback (DynamicLoaderMacOSXDYLD::NotifyBreakpointHit, this, true);
1505                 m_break_id = dyld_break->GetID();
1506             }
1507         }
1508     }
1509     return m_break_id != LLDB_INVALID_BREAK_ID;
1510 }
1511 
1512 //----------------------------------------------------------------------
1513 // Member function that gets called when the process state changes.
1514 //----------------------------------------------------------------------
1515 void
1516 DynamicLoaderMacOSXDYLD::PrivateProcessStateChanged (Process *process, StateType state)
1517 {
1518     DEBUG_PRINTF("DynamicLoaderMacOSXDYLD::%s(%s)\n", __FUNCTION__, StateAsCString(state));
1519     switch (state)
1520     {
1521     case eStateConnected:
1522     case eStateAttaching:
1523     case eStateLaunching:
1524     case eStateInvalid:
1525     case eStateUnloaded:
1526     case eStateExited:
1527     case eStateDetached:
1528         Clear(false);
1529         break;
1530 
1531     case eStateStopped:
1532         // Keep trying find dyld and set our notification breakpoint each time
1533         // we stop until we succeed
1534         if (!DidSetNotificationBreakpoint () && m_process->IsAlive())
1535         {
1536             if (NeedToLocateDYLD ())
1537                 LocateDYLD ();
1538 
1539             SetNotificationBreakpoint ();
1540         }
1541         break;
1542 
1543     case eStateRunning:
1544     case eStateStepping:
1545     case eStateCrashed:
1546     case eStateSuspended:
1547         break;
1548 
1549     default:
1550         break;
1551     }
1552 }
1553 
1554 // This bit in the n_desc field of the mach file means that this is a
1555 // stub that runs arbitrary code to determine the trampoline target.
1556 // We've established a naming convention with the CoreOS folks for the
1557 // equivalent symbols they will use for this (which the objc guys didn't follow...)
1558 // For now we'll just look for all symbols matching that naming convention...
1559 
1560 #define MACH_O_N_SYMBOL_RESOLVER 0x100
1561 
1562 ThreadPlanSP
1563 DynamicLoaderMacOSXDYLD::GetStepThroughTrampolinePlan (Thread &thread, bool stop_others)
1564 {
1565     ThreadPlanSP thread_plan_sp;
1566     StackFrame *current_frame = thread.GetStackFrameAtIndex(0).get();
1567     const SymbolContext &current_context = current_frame->GetSymbolContext(eSymbolContextSymbol);
1568     Symbol *current_symbol = current_context.symbol;
1569     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1570 
1571     if (current_symbol != NULL)
1572     {
1573         if (current_symbol->IsTrampoline())
1574         {
1575             const ConstString &trampoline_name = current_symbol->GetMangled().GetName(Mangled::ePreferMangled);
1576 
1577             if (trampoline_name)
1578             {
1579                 SymbolContextList target_symbols;
1580                 TargetSP target_sp (thread.CalculateTarget());
1581                 ModuleList &images = target_sp->GetImages();
1582 
1583                 images.FindSymbolsWithNameAndType(trampoline_name, eSymbolTypeCode, target_symbols);
1584 
1585                 size_t num_original_symbols = target_symbols.GetSize();
1586                 // FIXME: The resolver symbol is only valid in object files.  In binaries it is reused for the
1587                 // shared library slot number.  So we'll have to look this up in the dyld info.
1588                 // For now, just turn this off.
1589 
1590                 // bool orig_is_resolver = (current_symbol->GetFlags() & MACH_O_N_SYMBOL_RESOLVER) == MACH_O_N_SYMBOL_RESOLVER;
1591                 bool orig_is_resolver = false;
1592 
1593                 if (num_original_symbols > 0)
1594                 {
1595                     // We found symbols that look like they are the targets to our symbol.  Now look through the
1596                     // modules containing our symbols to see if there are any for our symbol.
1597 
1598                     ModuleList modules_to_search;
1599 
1600                     for (size_t i = 0; i < num_original_symbols; i++)
1601                     {
1602                         SymbolContext sc;
1603                         target_symbols.GetContextAtIndex(i, sc);
1604 
1605                         ModuleSP module_sp (sc.symbol->CalculateSymbolContextModule());
1606                         if (module_sp)
1607                              modules_to_search.AppendIfNeeded(module_sp);
1608                     }
1609 
1610                     // If the original stub symbol is a resolver, then we don't want to break on the symbol with the
1611                     // original name, but instead on all the symbols it could resolve to since otherwise we would stop
1612                     // in the middle of the resolution...
1613                     // Note that the stub is not of the resolver type it will point to the equivalent symbol,
1614                     // not the original name, so in that case we don't need to do anything.
1615 
1616                     if (orig_is_resolver)
1617                     {
1618                         target_symbols.Clear();
1619 
1620                         FindEquivalentSymbols (current_symbol, modules_to_search, target_symbols);
1621                     }
1622 
1623                     // FIXME - Make the Run to Address take multiple addresses, and
1624                     // run to any of them.
1625                     uint32_t num_symbols = target_symbols.GetSize();
1626                     if (num_symbols > 0)
1627                     {
1628                         std::vector<lldb::addr_t>  addresses;
1629                         addresses.resize (num_symbols);
1630                         for (uint32_t i = 0; i < num_symbols; i++)
1631                         {
1632                             SymbolContext context;
1633                             AddressRange addr_range;
1634                             if (target_symbols.GetContextAtIndex(i, context))
1635                             {
1636                                 context.GetAddressRange (eSymbolContextEverything, 0, false, addr_range);
1637                                 lldb::addr_t load_addr = addr_range.GetBaseAddress().GetLoadAddress(target_sp.get());
1638                                 addresses[i] = load_addr;
1639                             }
1640                         }
1641                         if (addresses.size() > 0)
1642                             thread_plan_sp.reset (new ThreadPlanRunToAddress (thread, addresses, stop_others));
1643                         else
1644                         {
1645                             if (log)
1646                                 log->Printf ("Couldn't resolve the symbol contexts.");
1647                         }
1648                     }
1649                     else
1650                     {
1651                         if (log)
1652                         {
1653                             log->Printf ("Found a resolver stub for: \"%s\" but could not find any symbols it resolves to.",
1654                                          trampoline_name.AsCString());
1655                         }
1656                     }
1657                 }
1658                 else
1659                 {
1660                     if (log)
1661                     {
1662                         log->Printf ("Could not find symbol for trampoline target: \"%s\"", trampoline_name.AsCString());
1663                     }
1664                 }
1665             }
1666         }
1667     }
1668     else
1669     {
1670         if (log)
1671             log->Printf ("Could not find symbol for step through.");
1672     }
1673 
1674     return thread_plan_sp;
1675 }
1676 
1677 size_t
1678 DynamicLoaderMacOSXDYLD::FindEquivalentSymbols (lldb_private::Symbol *original_symbol,
1679                                                lldb_private::ModuleList &images,
1680                                                lldb_private::SymbolContextList &equivalent_symbols)
1681 {
1682     const ConstString &trampoline_name = original_symbol->GetMangled().GetName(Mangled::ePreferMangled);
1683     if (!trampoline_name)
1684         return 0;
1685 
1686     size_t initial_size = equivalent_symbols.GetSize();
1687 
1688     static const char *resolver_name_regex = "(_gc|_non_gc|\\$[A-Z0-9]+)$";
1689     std::string equivalent_regex_buf("^");
1690     equivalent_regex_buf.append (trampoline_name.GetCString());
1691     equivalent_regex_buf.append (resolver_name_regex);
1692 
1693     RegularExpression equivalent_name_regex (equivalent_regex_buf.c_str());
1694     const bool append = true;
1695     images.FindSymbolsMatchingRegExAndType (equivalent_name_regex, eSymbolTypeCode, equivalent_symbols, append);
1696 
1697     return equivalent_symbols.GetSize() - initial_size;
1698 }
1699 
1700 Error
1701 DynamicLoaderMacOSXDYLD::CanLoadImage ()
1702 {
1703     Error error;
1704     // In order for us to tell if we can load a shared library we verify that
1705     // the dylib_info_addr isn't zero (which means no shared libraries have
1706     // been set yet, or dyld is currently mucking with the shared library list).
1707     if (ReadAllImageInfosStructure ())
1708     {
1709         // TODO: also check the _dyld_global_lock_held variable in libSystem.B.dylib?
1710         // TODO: check the malloc lock?
1711         // TODO: check the objective C lock?
1712         if (m_dyld_all_image_infos.dylib_info_addr != 0)
1713             return error; // Success
1714     }
1715 
1716     error.SetErrorString("unsafe to load or unload shared libraries");
1717     return error;
1718 }
1719 
1720 void
1721 DynamicLoaderMacOSXDYLD::Initialize()
1722 {
1723     PluginManager::RegisterPlugin (GetPluginNameStatic(),
1724                                    GetPluginDescriptionStatic(),
1725                                    CreateInstance);
1726 }
1727 
1728 void
1729 DynamicLoaderMacOSXDYLD::Terminate()
1730 {
1731     PluginManager::UnregisterPlugin (CreateInstance);
1732 }
1733 
1734 
1735 const char *
1736 DynamicLoaderMacOSXDYLD::GetPluginNameStatic()
1737 {
1738     return "dynamic-loader.macosx-dyld";
1739 }
1740 
1741 const char *
1742 DynamicLoaderMacOSXDYLD::GetPluginDescriptionStatic()
1743 {
1744     return "Dynamic loader plug-in that watches for shared library loads/unloads in MacOSX user processes.";
1745 }
1746 
1747 
1748 //------------------------------------------------------------------
1749 // PluginInterface protocol
1750 //------------------------------------------------------------------
1751 const char *
1752 DynamicLoaderMacOSXDYLD::GetPluginName()
1753 {
1754     return "DynamicLoaderMacOSXDYLD";
1755 }
1756 
1757 const char *
1758 DynamicLoaderMacOSXDYLD::GetShortPluginName()
1759 {
1760     return GetPluginNameStatic();
1761 }
1762 
1763 uint32_t
1764 DynamicLoaderMacOSXDYLD::GetPluginVersion()
1765 {
1766     return 1;
1767 }
1768 
1769