1 //===-- DynamicLoaderDarwin.cpp -----------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "DynamicLoaderDarwin.h"
10 
11 #include "lldb/Breakpoint/StoppointCallbackContext.h"
12 #include "lldb/Core/Debugger.h"
13 #include "lldb/Core/Module.h"
14 #include "lldb/Core/ModuleSpec.h"
15 #include "lldb/Core/PluginManager.h"
16 #include "lldb/Core/Section.h"
17 #include "lldb/Expression/DiagnosticManager.h"
18 #include "lldb/Host/FileSystem.h"
19 #include "lldb/Symbol/ClangASTContext.h"
20 #include "lldb/Symbol/Function.h"
21 #include "lldb/Symbol/ObjectFile.h"
22 #include "lldb/Target/ABI.h"
23 #include "lldb/Target/ObjCLanguageRuntime.h"
24 #include "lldb/Target/RegisterContext.h"
25 #include "lldb/Target/StackFrame.h"
26 #include "lldb/Target/Target.h"
27 #include "lldb/Target/Thread.h"
28 #include "lldb/Target/ThreadPlanCallFunction.h"
29 #include "lldb/Target/ThreadPlanRunToAddress.h"
30 #include "lldb/Utility/DataBuffer.h"
31 #include "lldb/Utility/DataBufferHeap.h"
32 #include "lldb/Utility/Log.h"
33 #include "lldb/Utility/State.h"
34 
35 //#define ENABLE_DEBUG_PRINTF // COMMENT THIS LINE OUT PRIOR TO CHECKIN
36 #ifdef ENABLE_DEBUG_PRINTF
37 #include <stdio.h>
38 #define DEBUG_PRINTF(fmt, ...) printf(fmt, ##__VA_ARGS__)
39 #else
40 #define DEBUG_PRINTF(fmt, ...)
41 #endif
42 
43 #ifndef __APPLE__
44 #include "Utility/UuidCompatibility.h"
45 #else
46 #include <uuid/uuid.h>
47 #endif
48 
49 #include <memory>
50 
51 using namespace lldb;
52 using namespace lldb_private;
53 
54 //----------------------------------------------------------------------
55 // Constructor
56 //----------------------------------------------------------------------
57 DynamicLoaderDarwin::DynamicLoaderDarwin(Process *process)
58     : DynamicLoader(process), m_dyld_module_wp(), m_libpthread_module_wp(),
59       m_pthread_getspecific_addr(), m_tid_to_tls_map(), m_dyld_image_infos(),
60       m_dyld_image_infos_stop_id(UINT32_MAX), m_dyld(), m_mutex() {}
61 
62 //----------------------------------------------------------------------
63 // Destructor
64 //----------------------------------------------------------------------
65 DynamicLoaderDarwin::~DynamicLoaderDarwin() {}
66 
67 //------------------------------------------------------------------
68 /// Called after attaching a process.
69 ///
70 /// Allow DynamicLoader plug-ins to execute some code after
71 /// attaching to a process.
72 //------------------------------------------------------------------
73 void DynamicLoaderDarwin::DidAttach() {
74   PrivateInitialize(m_process);
75   DoInitialImageFetch();
76   SetNotificationBreakpoint();
77 }
78 
79 //------------------------------------------------------------------
80 /// Called after attaching a process.
81 ///
82 /// Allow DynamicLoader plug-ins to execute some code after
83 /// attaching to a process.
84 //------------------------------------------------------------------
85 void DynamicLoaderDarwin::DidLaunch() {
86   PrivateInitialize(m_process);
87   DoInitialImageFetch();
88   SetNotificationBreakpoint();
89 }
90 
91 //----------------------------------------------------------------------
92 // Clear out the state of this class.
93 //----------------------------------------------------------------------
94 void DynamicLoaderDarwin::Clear(bool clear_process) {
95   std::lock_guard<std::recursive_mutex> guard(m_mutex);
96   if (clear_process)
97     m_process = NULL;
98   m_dyld_image_infos.clear();
99   m_dyld_image_infos_stop_id = UINT32_MAX;
100   m_dyld.Clear(false);
101 }
102 
103 ModuleSP DynamicLoaderDarwin::FindTargetModuleForImageInfo(
104     ImageInfo &image_info, bool can_create, bool *did_create_ptr) {
105   if (did_create_ptr)
106     *did_create_ptr = false;
107 
108   Target &target = m_process->GetTarget();
109   const ModuleList &target_images = target.GetImages();
110   ModuleSpec module_spec(image_info.file_spec);
111   module_spec.GetUUID() = image_info.uuid;
112   ModuleSP module_sp(target_images.FindFirstModule(module_spec));
113 
114   if (module_sp && !module_spec.GetUUID().IsValid() &&
115       !module_sp->GetUUID().IsValid()) {
116     // No UUID, we must rely upon the cached module modification time and the
117     // modification time of the file on disk
118     if (module_sp->GetModificationTime() !=
119         FileSystem::Instance().GetModificationTime(module_sp->GetFileSpec()))
120       module_sp.reset();
121   }
122 
123   if (!module_sp) {
124     if (can_create) {
125       module_sp = target.GetSharedModule(module_spec);
126       if (!module_sp || module_sp->GetObjectFile() == NULL)
127         module_sp = m_process->ReadModuleFromMemory(image_info.file_spec,
128                                                     image_info.address);
129 
130       if (did_create_ptr)
131         *did_create_ptr = (bool)module_sp;
132     }
133   }
134   return module_sp;
135 }
136 
137 void DynamicLoaderDarwin::UnloadImages(
138     const std::vector<lldb::addr_t> &solib_addresses) {
139   std::lock_guard<std::recursive_mutex> guard(m_mutex);
140   if (m_process->GetStopID() == m_dyld_image_infos_stop_id)
141     return;
142 
143   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
144   Target &target = m_process->GetTarget();
145   if (log)
146     log->Printf("Removing %" PRId64 " modules.",
147                 (uint64_t)solib_addresses.size());
148 
149   ModuleList unloaded_module_list;
150 
151   for (addr_t solib_addr : solib_addresses) {
152     Address header;
153     if (header.SetLoadAddress(solib_addr, &target)) {
154       if (header.GetOffset() == 0) {
155         ModuleSP module_to_remove(header.GetModule());
156         if (module_to_remove.get()) {
157           if (log)
158             log->Printf("Removing module at address 0x%" PRIx64, solib_addr);
159           // remove the sections from the Target
160           UnloadSections(module_to_remove);
161           // add this to the list of modules to remove
162           unloaded_module_list.AppendIfNeeded(module_to_remove);
163           // remove the entry from the m_dyld_image_infos
164           ImageInfo::collection::iterator pos, end = m_dyld_image_infos.end();
165           for (pos = m_dyld_image_infos.begin(); pos != end; pos++) {
166             if (solib_addr == (*pos).address) {
167               m_dyld_image_infos.erase(pos);
168               break;
169             }
170           }
171         }
172       }
173     }
174   }
175 
176   if (unloaded_module_list.GetSize() > 0) {
177     if (log) {
178       log->PutCString("Unloaded:");
179       unloaded_module_list.LogUUIDAndPaths(
180           log, "DynamicLoaderDarwin::UnloadModules");
181     }
182     m_process->GetTarget().GetImages().Remove(unloaded_module_list);
183     m_dyld_image_infos_stop_id = m_process->GetStopID();
184   }
185 }
186 
187 void DynamicLoaderDarwin::UnloadAllImages() {
188   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
189   ModuleList unloaded_modules_list;
190 
191   Target &target = m_process->GetTarget();
192   const ModuleList &target_modules = target.GetImages();
193   std::lock_guard<std::recursive_mutex> guard(target_modules.GetMutex());
194 
195   size_t num_modules = target_modules.GetSize();
196   ModuleSP dyld_sp(GetDYLDModule());
197 
198   for (size_t i = 0; i < num_modules; i++) {
199     ModuleSP module_sp = target_modules.GetModuleAtIndexUnlocked(i);
200 
201     // Don't remove dyld - else we'll lose our breakpoint notifying us about
202     // libraries being re-loaded...
203     if (module_sp.get() != nullptr && module_sp.get() != dyld_sp.get()) {
204       UnloadSections(module_sp);
205       unloaded_modules_list.Append(module_sp);
206     }
207   }
208 
209   if (unloaded_modules_list.GetSize() != 0) {
210     if (log) {
211       log->PutCString("Unloaded:");
212       unloaded_modules_list.LogUUIDAndPaths(
213           log, "DynamicLoaderDarwin::UnloadAllImages");
214     }
215     target.GetImages().Remove(unloaded_modules_list);
216     m_dyld_image_infos.clear();
217     m_dyld_image_infos_stop_id = m_process->GetStopID();
218   }
219 }
220 
221 //----------------------------------------------------------------------
222 // Update the load addresses for all segments in MODULE using the updated INFO
223 // that is passed in.
224 //----------------------------------------------------------------------
225 bool DynamicLoaderDarwin::UpdateImageLoadAddress(Module *module,
226                                                  ImageInfo &info) {
227   bool changed = false;
228   if (module) {
229     ObjectFile *image_object_file = module->GetObjectFile();
230     if (image_object_file) {
231       SectionList *section_list = image_object_file->GetSectionList();
232       if (section_list) {
233         std::vector<uint32_t> inaccessible_segment_indexes;
234         // We now know the slide amount, so go through all sections and update
235         // the load addresses with the correct values.
236         const size_t num_segments = info.segments.size();
237         for (size_t i = 0; i < num_segments; ++i) {
238           // Only load a segment if it has protections. Things like __PAGEZERO
239           // don't have any protections, and they shouldn't be slid
240           SectionSP section_sp(
241               section_list->FindSectionByName(info.segments[i].name));
242 
243           if (info.segments[i].maxprot == 0) {
244             inaccessible_segment_indexes.push_back(i);
245           } else {
246             const addr_t new_section_load_addr =
247                 info.segments[i].vmaddr + info.slide;
248             static ConstString g_section_name_LINKEDIT("__LINKEDIT");
249 
250             if (section_sp) {
251               // __LINKEDIT sections from files in the shared cache can overlap
252               // so check to see what the segment name is and pass "false" so
253               // we don't warn of overlapping "Section" objects, and "true" for
254               // all other sections.
255               const bool warn_multiple =
256                   section_sp->GetName() != g_section_name_LINKEDIT;
257 
258               changed = m_process->GetTarget().SetSectionLoadAddress(
259                   section_sp, new_section_load_addr, warn_multiple);
260             }
261           }
262         }
263 
264         // If the loaded the file (it changed) and we have segments that are
265         // not readable or writeable, add them to the invalid memory region
266         // cache for the process. This will typically only be the __PAGEZERO
267         // segment in the main executable. We might be able to apply this more
268         // generally to more sections that have no protections in the future,
269         // but for now we are going to just do __PAGEZERO.
270         if (changed && !inaccessible_segment_indexes.empty()) {
271           for (uint32_t i = 0; i < inaccessible_segment_indexes.size(); ++i) {
272             const uint32_t seg_idx = inaccessible_segment_indexes[i];
273             SectionSP section_sp(
274                 section_list->FindSectionByName(info.segments[seg_idx].name));
275 
276             if (section_sp) {
277               static ConstString g_pagezero_section_name("__PAGEZERO");
278               if (g_pagezero_section_name == section_sp->GetName()) {
279                 // __PAGEZERO never slides...
280                 const lldb::addr_t vmaddr = info.segments[seg_idx].vmaddr;
281                 const lldb::addr_t vmsize = info.segments[seg_idx].vmsize;
282                 Process::LoadRange pagezero_range(vmaddr, vmsize);
283                 m_process->AddInvalidMemoryRegion(pagezero_range);
284               }
285             }
286           }
287         }
288       }
289     }
290   }
291   // We might have an in memory image that was loaded as soon as it was created
292   if (info.load_stop_id == m_process->GetStopID())
293     changed = true;
294   else if (changed) {
295     // Update the stop ID when this library was updated
296     info.load_stop_id = m_process->GetStopID();
297   }
298   return changed;
299 }
300 
301 //----------------------------------------------------------------------
302 // Unload the segments in MODULE using the INFO that is passed in.
303 //----------------------------------------------------------------------
304 bool DynamicLoaderDarwin::UnloadModuleSections(Module *module,
305                                                ImageInfo &info) {
306   bool changed = false;
307   if (module) {
308     ObjectFile *image_object_file = module->GetObjectFile();
309     if (image_object_file) {
310       SectionList *section_list = image_object_file->GetSectionList();
311       if (section_list) {
312         const size_t num_segments = info.segments.size();
313         for (size_t i = 0; i < num_segments; ++i) {
314           SectionSP section_sp(
315               section_list->FindSectionByName(info.segments[i].name));
316           if (section_sp) {
317             const addr_t old_section_load_addr =
318                 info.segments[i].vmaddr + info.slide;
319             if (m_process->GetTarget().SetSectionUnloaded(
320                     section_sp, old_section_load_addr))
321               changed = true;
322           } else {
323             Host::SystemLog(Host::eSystemLogWarning,
324                             "warning: unable to find and unload segment named "
325                             "'%s' in '%s' in macosx dynamic loader plug-in.\n",
326                             info.segments[i].name.AsCString("<invalid>"),
327                             image_object_file->GetFileSpec().GetPath().c_str());
328           }
329         }
330       }
331     }
332   }
333   return changed;
334 }
335 
336 // Given a JSON dictionary (from debugserver, most likely) of binary images
337 // loaded in the inferior process, add the images to the ImageInfo collection.
338 
339 bool DynamicLoaderDarwin::JSONImageInformationIntoImageInfo(
340     StructuredData::ObjectSP image_details,
341     ImageInfo::collection &image_infos) {
342   StructuredData::ObjectSP images_sp =
343       image_details->GetAsDictionary()->GetValueForKey("images");
344   if (images_sp.get() == nullptr)
345     return false;
346 
347   image_infos.resize(images_sp->GetAsArray()->GetSize());
348 
349   for (size_t i = 0; i < image_infos.size(); i++) {
350     StructuredData::ObjectSP image_sp =
351         images_sp->GetAsArray()->GetItemAtIndex(i);
352     if (image_sp.get() == nullptr || image_sp->GetAsDictionary() == nullptr)
353       return false;
354     StructuredData::Dictionary *image = image_sp->GetAsDictionary();
355     // clang-format off
356     if (!image->HasKey("load_address") ||
357         !image->HasKey("pathname") ||
358         !image->HasKey("mod_date") ||
359         !image->HasKey("mach_header") ||
360         image->GetValueForKey("mach_header")->GetAsDictionary() == nullptr ||
361         !image->HasKey("segments") ||
362         image->GetValueForKey("segments")->GetAsArray() == nullptr ||
363         !image->HasKey("uuid")) {
364       return false;
365     }
366     // clang-format on
367     image_infos[i].address =
368         image->GetValueForKey("load_address")->GetAsInteger()->GetValue();
369     image_infos[i].mod_date =
370         image->GetValueForKey("mod_date")->GetAsInteger()->GetValue();
371     image_infos[i].file_spec.SetFile(
372         image->GetValueForKey("pathname")->GetAsString()->GetValue(),
373         FileSpec::Style::native);
374 
375     StructuredData::Dictionary *mh =
376         image->GetValueForKey("mach_header")->GetAsDictionary();
377     image_infos[i].header.magic =
378         mh->GetValueForKey("magic")->GetAsInteger()->GetValue();
379     image_infos[i].header.cputype =
380         mh->GetValueForKey("cputype")->GetAsInteger()->GetValue();
381     image_infos[i].header.cpusubtype =
382         mh->GetValueForKey("cpusubtype")->GetAsInteger()->GetValue();
383     image_infos[i].header.filetype =
384         mh->GetValueForKey("filetype")->GetAsInteger()->GetValue();
385 
386     if (image->HasKey("min_version_os_name")) {
387       std::string os_name = image->GetValueForKey("min_version_os_name")
388                                 ->GetAsString()
389                                 ->GetValue();
390       if (os_name == "macosx")
391         image_infos[i].os_type = llvm::Triple::MacOSX;
392       else if (os_name == "ios" || os_name == "iphoneos")
393         image_infos[i].os_type = llvm::Triple::IOS;
394       else if (os_name == "tvos")
395         image_infos[i].os_type = llvm::Triple::TvOS;
396       else if (os_name == "watchos")
397         image_infos[i].os_type = llvm::Triple::WatchOS;
398       // NEED_BRIDGEOS_TRIPLE else if (os_name == "bridgeos")
399       // NEED_BRIDGEOS_TRIPLE   image_infos[i].os_type = llvm::Triple::BridgeOS;
400     }
401     if (image->HasKey("min_version_os_sdk")) {
402       image_infos[i].min_version_os_sdk =
403           image->GetValueForKey("min_version_os_sdk")
404               ->GetAsString()
405               ->GetValue();
406     }
407 
408     // Fields that aren't used by DynamicLoaderDarwin so debugserver doesn't
409     // currently send them in the reply.
410 
411     if (mh->HasKey("flags"))
412       image_infos[i].header.flags =
413           mh->GetValueForKey("flags")->GetAsInteger()->GetValue();
414     else
415       image_infos[i].header.flags = 0;
416 
417     if (mh->HasKey("ncmds"))
418       image_infos[i].header.ncmds =
419           mh->GetValueForKey("ncmds")->GetAsInteger()->GetValue();
420     else
421       image_infos[i].header.ncmds = 0;
422 
423     if (mh->HasKey("sizeofcmds"))
424       image_infos[i].header.sizeofcmds =
425           mh->GetValueForKey("sizeofcmds")->GetAsInteger()->GetValue();
426     else
427       image_infos[i].header.sizeofcmds = 0;
428 
429     StructuredData::Array *segments =
430         image->GetValueForKey("segments")->GetAsArray();
431     uint32_t segcount = segments->GetSize();
432     for (size_t j = 0; j < segcount; j++) {
433       Segment segment;
434       StructuredData::Dictionary *seg =
435           segments->GetItemAtIndex(j)->GetAsDictionary();
436       segment.name =
437           ConstString(seg->GetValueForKey("name")->GetAsString()->GetValue());
438       segment.vmaddr =
439           seg->GetValueForKey("vmaddr")->GetAsInteger()->GetValue();
440       segment.vmsize =
441           seg->GetValueForKey("vmsize")->GetAsInteger()->GetValue();
442       segment.fileoff =
443           seg->GetValueForKey("fileoff")->GetAsInteger()->GetValue();
444       segment.filesize =
445           seg->GetValueForKey("filesize")->GetAsInteger()->GetValue();
446       segment.maxprot =
447           seg->GetValueForKey("maxprot")->GetAsInteger()->GetValue();
448 
449       // Fields that aren't used by DynamicLoaderDarwin so debugserver doesn't
450       // currently send them in the reply.
451 
452       if (seg->HasKey("initprot"))
453         segment.initprot =
454             seg->GetValueForKey("initprot")->GetAsInteger()->GetValue();
455       else
456         segment.initprot = 0;
457 
458       if (seg->HasKey("flags"))
459         segment.flags =
460             seg->GetValueForKey("flags")->GetAsInteger()->GetValue();
461       else
462         segment.flags = 0;
463 
464       if (seg->HasKey("nsects"))
465         segment.nsects =
466             seg->GetValueForKey("nsects")->GetAsInteger()->GetValue();
467       else
468         segment.nsects = 0;
469 
470       image_infos[i].segments.push_back(segment);
471     }
472 
473     image_infos[i].uuid.SetFromOptionalStringRef(
474         image->GetValueForKey("uuid")->GetAsString()->GetValue());
475 
476     // All sections listed in the dyld image info structure will all either be
477     // fixed up already, or they will all be off by a single slide amount that
478     // is determined by finding the first segment that is at file offset zero
479     // which also has bytes (a file size that is greater than zero) in the
480     // object file.
481 
482     // Determine the slide amount (if any)
483     const size_t num_sections = image_infos[i].segments.size();
484     for (size_t k = 0; k < num_sections; ++k) {
485       // Iterate through the object file sections to find the first section
486       // that starts of file offset zero and that has bytes in the file...
487       if ((image_infos[i].segments[k].fileoff == 0 &&
488            image_infos[i].segments[k].filesize > 0) ||
489           (image_infos[i].segments[k].name == ConstString("__TEXT"))) {
490         image_infos[i].slide =
491             image_infos[i].address - image_infos[i].segments[k].vmaddr;
492         // We have found the slide amount, so we can exit this for loop.
493         break;
494       }
495     }
496   }
497 
498   return true;
499 }
500 
501 void DynamicLoaderDarwin::UpdateSpecialBinariesFromNewImageInfos(
502     ImageInfo::collection &image_infos) {
503   uint32_t exe_idx = UINT32_MAX;
504   uint32_t dyld_idx = UINT32_MAX;
505   Target &target = m_process->GetTarget();
506   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
507   ConstString g_dyld_sim_filename("dyld_sim");
508 
509   ArchSpec target_arch = target.GetArchitecture();
510   const size_t image_infos_size = image_infos.size();
511   for (size_t i = 0; i < image_infos_size; i++) {
512     if (image_infos[i].header.filetype == llvm::MachO::MH_DYLINKER) {
513       // In a "simulator" process (an x86 process that is
514       // ios/tvos/watchos/bridgeos) we will have two dyld modules --
515       // a "dyld" that we want to keep track of, and a "dyld_sim" which
516       // we don't need to keep track of here. If the target is an x86
517       // system and the OS of the dyld binary is ios/tvos/watchos/bridgeos,
518       // then we are looking at dyld_sym.
519 
520       // debugserver has only recently (late 2016) started sending up the os
521       // type for each binary it sees -- so if we don't have an os type, use a
522       // filename check as our next best guess.
523       if (image_infos[i].os_type == llvm::Triple::OSType::UnknownOS) {
524         if (image_infos[i].file_spec.GetFilename() != g_dyld_sim_filename) {
525           dyld_idx = i;
526         }
527       } else if (target_arch.GetTriple().getArch() == llvm::Triple::x86 ||
528                  target_arch.GetTriple().getArch() == llvm::Triple::x86_64) {
529         if (image_infos[i].os_type != llvm::Triple::OSType::IOS &&
530             image_infos[i].os_type != llvm::Triple::TvOS &&
531             image_infos[i].os_type != llvm::Triple::WatchOS) {
532             // NEED_BRIDGEOS_TRIPLE image_infos[i].os_type != llvm::Triple::BridgeOS) {
533           dyld_idx = i;
534         }
535       }
536       else {
537         // catch-all for any other environment -- trust that dyld is actually
538         // dyld
539         dyld_idx = i;
540       }
541     } else if (image_infos[i].header.filetype == llvm::MachO::MH_EXECUTE) {
542       exe_idx = i;
543     }
544   }
545 
546   if (exe_idx != UINT32_MAX) {
547     const bool can_create = true;
548     ModuleSP exe_module_sp(
549         FindTargetModuleForImageInfo(image_infos[exe_idx], can_create, NULL));
550     if (exe_module_sp) {
551       if (log)
552         log->Printf("Found executable module: %s",
553                     exe_module_sp->GetFileSpec().GetPath().c_str());
554       target.GetImages().AppendIfNeeded(exe_module_sp);
555       UpdateImageLoadAddress(exe_module_sp.get(), image_infos[exe_idx]);
556       if (exe_module_sp.get() != target.GetExecutableModulePointer()) {
557         target.SetExecutableModule(exe_module_sp, eLoadDependentsNo);
558       }
559     }
560   }
561 
562   if (dyld_idx != UINT32_MAX) {
563     const bool can_create = true;
564     ModuleSP dyld_sp =
565         FindTargetModuleForImageInfo(image_infos[dyld_idx], can_create, NULL);
566     if (dyld_sp.get()) {
567       if (log)
568         log->Printf("Found dyld module: %s",
569                     dyld_sp->GetFileSpec().GetPath().c_str());
570       target.GetImages().AppendIfNeeded(dyld_sp);
571       UpdateImageLoadAddress(dyld_sp.get(), image_infos[dyld_idx]);
572       SetDYLDModule(dyld_sp);
573     }
574   }
575 }
576 
577 void DynamicLoaderDarwin::UpdateDYLDImageInfoFromNewImageInfo(
578     ImageInfo &image_info) {
579   if (image_info.header.filetype == llvm::MachO::MH_DYLINKER) {
580     const bool can_create = true;
581     ModuleSP dyld_sp =
582         FindTargetModuleForImageInfo(image_info, can_create, NULL);
583     if (dyld_sp.get()) {
584       Target &target = m_process->GetTarget();
585       target.GetImages().AppendIfNeeded(dyld_sp);
586       UpdateImageLoadAddress(dyld_sp.get(), image_info);
587       SetDYLDModule(dyld_sp);
588     }
589   }
590 }
591 
592 void DynamicLoaderDarwin::SetDYLDModule(lldb::ModuleSP &dyld_module_sp) {
593   m_dyld_module_wp = dyld_module_sp;
594 }
595 
596 ModuleSP DynamicLoaderDarwin::GetDYLDModule() {
597   ModuleSP dyld_sp(m_dyld_module_wp.lock());
598   return dyld_sp;
599 }
600 
601 bool DynamicLoaderDarwin::AddModulesUsingImageInfos(
602     ImageInfo::collection &image_infos) {
603   std::lock_guard<std::recursive_mutex> guard(m_mutex);
604   // Now add these images to the main list.
605   ModuleList loaded_module_list;
606   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
607   Target &target = m_process->GetTarget();
608   ModuleList &target_images = target.GetImages();
609 
610   for (uint32_t idx = 0; idx < image_infos.size(); ++idx) {
611     if (log) {
612       log->Printf("Adding new image at address=0x%16.16" PRIx64 ".",
613                   image_infos[idx].address);
614       image_infos[idx].PutToLog(log);
615     }
616 
617     m_dyld_image_infos.push_back(image_infos[idx]);
618 
619     ModuleSP image_module_sp(
620         FindTargetModuleForImageInfo(image_infos[idx], true, NULL));
621 
622     if (image_module_sp) {
623       ObjectFile *objfile = image_module_sp->GetObjectFile();
624       if (objfile) {
625         SectionList *sections = objfile->GetSectionList();
626         if (sections) {
627           ConstString commpage_dbstr("__commpage");
628           Section *commpage_section =
629               sections->FindSectionByName(commpage_dbstr).get();
630           if (commpage_section) {
631             ModuleSpec module_spec(objfile->GetFileSpec(),
632                                    image_infos[idx].GetArchitecture());
633             module_spec.GetObjectName() = commpage_dbstr;
634             ModuleSP commpage_image_module_sp(
635                 target_images.FindFirstModule(module_spec));
636             if (!commpage_image_module_sp) {
637               module_spec.SetObjectOffset(objfile->GetFileOffset() +
638                                           commpage_section->GetFileOffset());
639               module_spec.SetObjectSize(objfile->GetByteSize());
640               commpage_image_module_sp = target.GetSharedModule(module_spec);
641               if (!commpage_image_module_sp ||
642                   commpage_image_module_sp->GetObjectFile() == NULL) {
643                 commpage_image_module_sp = m_process->ReadModuleFromMemory(
644                     image_infos[idx].file_spec, image_infos[idx].address);
645                 // Always load a memory image right away in the target in case
646                 // we end up trying to read the symbol table from memory... The
647                 // __LINKEDIT will need to be mapped so we can figure out where
648                 // the symbol table bits are...
649                 bool changed = false;
650                 UpdateImageLoadAddress(commpage_image_module_sp.get(),
651                                        image_infos[idx]);
652                 target.GetImages().Append(commpage_image_module_sp);
653                 if (changed) {
654                   image_infos[idx].load_stop_id = m_process->GetStopID();
655                   loaded_module_list.AppendIfNeeded(commpage_image_module_sp);
656                 }
657               }
658             }
659           }
660         }
661       }
662 
663       // UpdateImageLoadAddress will return true if any segments change load
664       // address. We need to check this so we don't mention that all loaded
665       // shared libraries are newly loaded each time we hit out dyld breakpoint
666       // since dyld will list all shared libraries each time.
667       if (UpdateImageLoadAddress(image_module_sp.get(), image_infos[idx])) {
668         target_images.AppendIfNeeded(image_module_sp);
669         loaded_module_list.AppendIfNeeded(image_module_sp);
670       }
671     }
672   }
673 
674   if (loaded_module_list.GetSize() > 0) {
675     if (log)
676       loaded_module_list.LogUUIDAndPaths(log,
677                                          "DynamicLoaderDarwin::ModulesDidLoad");
678     m_process->GetTarget().ModulesDidLoad(loaded_module_list);
679   }
680   return true;
681 }
682 
683 //----------------------------------------------------------------------
684 // On Mac OS X libobjc (the Objective-C runtime) has several critical dispatch
685 // functions written in hand-written assembly, and also have hand-written
686 // unwind information in the eh_frame section.  Normally we prefer analyzing
687 // the assembly instructions of a currently executing frame to unwind from that
688 // frame -- but on hand-written functions this profiling can fail.  We should
689 // use the eh_frame instructions for these functions all the time.
690 //
691 // As an aside, it would be better if the eh_frame entries had a flag (or were
692 // extensible so they could have an Apple-specific flag) which indicates that
693 // the instructions are asynchronous -- accurate at every instruction, instead
694 // of our normal default assumption that they are not.
695 //----------------------------------------------------------------------
696 
697 bool DynamicLoaderDarwin::AlwaysRelyOnEHUnwindInfo(SymbolContext &sym_ctx) {
698   ModuleSP module_sp;
699   if (sym_ctx.symbol) {
700     module_sp = sym_ctx.symbol->GetAddressRef().GetModule();
701   }
702   if (module_sp.get() == NULL && sym_ctx.function) {
703     module_sp =
704         sym_ctx.function->GetAddressRange().GetBaseAddress().GetModule();
705   }
706   if (module_sp.get() == NULL)
707     return false;
708 
709   ObjCLanguageRuntime *objc_runtime = m_process->GetObjCLanguageRuntime();
710   return objc_runtime != NULL && objc_runtime->IsModuleObjCLibrary(module_sp);
711 }
712 
713 //----------------------------------------------------------------------
714 // Dump a Segment to the file handle provided.
715 //----------------------------------------------------------------------
716 void DynamicLoaderDarwin::Segment::PutToLog(Log *log,
717                                             lldb::addr_t slide) const {
718   if (log) {
719     if (slide == 0)
720       log->Printf("\t\t%16s [0x%16.16" PRIx64 " - 0x%16.16" PRIx64 ")",
721                   name.AsCString(""), vmaddr + slide, vmaddr + slide + vmsize);
722     else
723       log->Printf("\t\t%16s [0x%16.16" PRIx64 " - 0x%16.16" PRIx64
724                   ") slide = 0x%" PRIx64,
725                   name.AsCString(""), vmaddr + slide, vmaddr + slide + vmsize,
726                   slide);
727   }
728 }
729 
730 const DynamicLoaderDarwin::Segment *
731 DynamicLoaderDarwin::ImageInfo::FindSegment(ConstString name) const {
732   const size_t num_segments = segments.size();
733   for (size_t i = 0; i < num_segments; ++i) {
734     if (segments[i].name == name)
735       return &segments[i];
736   }
737   return NULL;
738 }
739 
740 //----------------------------------------------------------------------
741 // Dump an image info structure to the file handle provided.
742 //----------------------------------------------------------------------
743 void DynamicLoaderDarwin::ImageInfo::PutToLog(Log *log) const {
744   if (!log)
745     return;
746   if (address == LLDB_INVALID_ADDRESS) {
747     LLDB_LOG(log, "modtime={0:x+8} uuid={1} path='{2}' (UNLOADED)", mod_date,
748              uuid.GetAsString(), file_spec.GetPath());
749   } else {
750     LLDB_LOG(log, "address={0:x+16} modtime={1:x+8} uuid={2} path='{3}'",
751              address, mod_date, uuid.GetAsString(), file_spec.GetPath());
752     for (uint32_t i = 0; i < segments.size(); ++i)
753       segments[i].PutToLog(log, slide);
754   }
755 }
756 
757 void DynamicLoaderDarwin::PrivateInitialize(Process *process) {
758   DEBUG_PRINTF("DynamicLoaderDarwin::%s() process state = %s\n", __FUNCTION__,
759                StateAsCString(m_process->GetState()));
760   Clear(true);
761   m_process = process;
762   m_process->GetTarget().ClearAllLoadedSections();
763 }
764 
765 //----------------------------------------------------------------------
766 // Member function that gets called when the process state changes.
767 //----------------------------------------------------------------------
768 void DynamicLoaderDarwin::PrivateProcessStateChanged(Process *process,
769                                                      StateType state) {
770   DEBUG_PRINTF("DynamicLoaderDarwin::%s(%s)\n", __FUNCTION__,
771                StateAsCString(state));
772   switch (state) {
773   case eStateConnected:
774   case eStateAttaching:
775   case eStateLaunching:
776   case eStateInvalid:
777   case eStateUnloaded:
778   case eStateExited:
779   case eStateDetached:
780     Clear(false);
781     break;
782 
783   case eStateStopped:
784     // Keep trying find dyld and set our notification breakpoint each time we
785     // stop until we succeed
786     if (!DidSetNotificationBreakpoint() && m_process->IsAlive()) {
787       if (NeedToDoInitialImageFetch())
788         DoInitialImageFetch();
789 
790       SetNotificationBreakpoint();
791     }
792     break;
793 
794   case eStateRunning:
795   case eStateStepping:
796   case eStateCrashed:
797   case eStateSuspended:
798     break;
799   }
800 }
801 
802 ThreadPlanSP
803 DynamicLoaderDarwin::GetStepThroughTrampolinePlan(Thread &thread,
804                                                   bool stop_others) {
805   ThreadPlanSP thread_plan_sp;
806   StackFrame *current_frame = thread.GetStackFrameAtIndex(0).get();
807   const SymbolContext &current_context =
808       current_frame->GetSymbolContext(eSymbolContextSymbol);
809   Symbol *current_symbol = current_context.symbol;
810   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
811   TargetSP target_sp(thread.CalculateTarget());
812 
813   if (current_symbol != NULL) {
814     std::vector<Address> addresses;
815 
816     if (current_symbol->IsTrampoline()) {
817       ConstString trampoline_name = current_symbol->GetMangled().GetName(
818           current_symbol->GetLanguage(), Mangled::ePreferMangled);
819 
820       if (trampoline_name) {
821         const ModuleList &images = target_sp->GetImages();
822 
823         SymbolContextList code_symbols;
824         images.FindSymbolsWithNameAndType(trampoline_name, eSymbolTypeCode,
825                                           code_symbols);
826         size_t num_code_symbols = code_symbols.GetSize();
827 
828         if (num_code_symbols > 0) {
829           for (uint32_t i = 0; i < num_code_symbols; i++) {
830             SymbolContext context;
831             AddressRange addr_range;
832             if (code_symbols.GetContextAtIndex(i, context)) {
833               context.GetAddressRange(eSymbolContextEverything, 0, false,
834                                       addr_range);
835               addresses.push_back(addr_range.GetBaseAddress());
836               if (log) {
837                 addr_t load_addr =
838                     addr_range.GetBaseAddress().GetLoadAddress(target_sp.get());
839 
840                 log->Printf("Found a trampoline target symbol at 0x%" PRIx64
841                             ".",
842                             load_addr);
843               }
844             }
845           }
846         }
847 
848         SymbolContextList reexported_symbols;
849         images.FindSymbolsWithNameAndType(
850             trampoline_name, eSymbolTypeReExported, reexported_symbols);
851         size_t num_reexported_symbols = reexported_symbols.GetSize();
852         if (num_reexported_symbols > 0) {
853           for (uint32_t i = 0; i < num_reexported_symbols; i++) {
854             SymbolContext context;
855             if (reexported_symbols.GetContextAtIndex(i, context)) {
856               if (context.symbol) {
857                 Symbol *actual_symbol =
858                     context.symbol->ResolveReExportedSymbol(*target_sp.get());
859                 if (actual_symbol) {
860                   const Address actual_symbol_addr =
861                       actual_symbol->GetAddress();
862                   if (actual_symbol_addr.IsValid()) {
863                     addresses.push_back(actual_symbol_addr);
864                     if (log) {
865                       lldb::addr_t load_addr =
866                           actual_symbol_addr.GetLoadAddress(target_sp.get());
867                       log->Printf(
868                           "Found a re-exported symbol: %s at 0x%" PRIx64 ".",
869                           actual_symbol->GetName().GetCString(), load_addr);
870                     }
871                   }
872                 }
873               }
874             }
875           }
876         }
877 
878         SymbolContextList indirect_symbols;
879         images.FindSymbolsWithNameAndType(trampoline_name, eSymbolTypeResolver,
880                                           indirect_symbols);
881         size_t num_indirect_symbols = indirect_symbols.GetSize();
882         if (num_indirect_symbols > 0) {
883           for (uint32_t i = 0; i < num_indirect_symbols; i++) {
884             SymbolContext context;
885             AddressRange addr_range;
886             if (indirect_symbols.GetContextAtIndex(i, context)) {
887               context.GetAddressRange(eSymbolContextEverything, 0, false,
888                                       addr_range);
889               addresses.push_back(addr_range.GetBaseAddress());
890               if (log) {
891                 addr_t load_addr =
892                     addr_range.GetBaseAddress().GetLoadAddress(target_sp.get());
893 
894                 log->Printf("Found an indirect target symbol at 0x%" PRIx64 ".",
895                             load_addr);
896               }
897             }
898           }
899         }
900       }
901     } else if (current_symbol->GetType() == eSymbolTypeReExported) {
902       // I am not sure we could ever end up stopped AT a re-exported symbol.
903       // But just in case:
904 
905       const Symbol *actual_symbol =
906           current_symbol->ResolveReExportedSymbol(*(target_sp.get()));
907       if (actual_symbol) {
908         Address target_addr(actual_symbol->GetAddress());
909         if (target_addr.IsValid()) {
910           if (log)
911             log->Printf(
912                 "Found a re-exported symbol: %s pointing to: %s at 0x%" PRIx64
913                 ".",
914                 current_symbol->GetName().GetCString(),
915                 actual_symbol->GetName().GetCString(),
916                 target_addr.GetLoadAddress(target_sp.get()));
917           addresses.push_back(target_addr.GetLoadAddress(target_sp.get()));
918         }
919       }
920     }
921 
922     if (addresses.size() > 0) {
923       // First check whether any of the addresses point to Indirect symbols,
924       // and if they do, resolve them:
925       std::vector<lldb::addr_t> load_addrs;
926       for (Address address : addresses) {
927         Symbol *symbol = address.CalculateSymbolContextSymbol();
928         if (symbol && symbol->IsIndirect()) {
929           Status error;
930           Address symbol_address = symbol->GetAddress();
931           addr_t resolved_addr = thread.GetProcess()->ResolveIndirectFunction(
932               &symbol_address, error);
933           if (error.Success()) {
934             load_addrs.push_back(resolved_addr);
935             if (log)
936               log->Printf("ResolveIndirectFunction found resolved target for "
937                           "%s at 0x%" PRIx64 ".",
938                           symbol->GetName().GetCString(), resolved_addr);
939           }
940         } else {
941           load_addrs.push_back(address.GetLoadAddress(target_sp.get()));
942         }
943       }
944       thread_plan_sp = std::make_shared<ThreadPlanRunToAddress>(
945           thread, load_addrs, stop_others);
946     }
947   } else {
948     if (log)
949       log->Printf("Could not find symbol for step through.");
950   }
951 
952   return thread_plan_sp;
953 }
954 
955 size_t DynamicLoaderDarwin::FindEquivalentSymbols(
956     lldb_private::Symbol *original_symbol, lldb_private::ModuleList &images,
957     lldb_private::SymbolContextList &equivalent_symbols) {
958   ConstString trampoline_name = original_symbol->GetMangled().GetName(
959       original_symbol->GetLanguage(), Mangled::ePreferMangled);
960   if (!trampoline_name)
961     return 0;
962 
963   size_t initial_size = equivalent_symbols.GetSize();
964 
965   static const char *resolver_name_regex = "(_gc|_non_gc|\\$[A-Za-z0-9\\$]+)$";
966   std::string equivalent_regex_buf("^");
967   equivalent_regex_buf.append(trampoline_name.GetCString());
968   equivalent_regex_buf.append(resolver_name_regex);
969 
970   RegularExpression equivalent_name_regex(equivalent_regex_buf);
971   const bool append = true;
972   images.FindSymbolsMatchingRegExAndType(equivalent_name_regex, eSymbolTypeCode,
973                                          equivalent_symbols, append);
974 
975   return equivalent_symbols.GetSize() - initial_size;
976 }
977 
978 lldb::ModuleSP DynamicLoaderDarwin::GetPThreadLibraryModule() {
979   ModuleSP module_sp = m_libpthread_module_wp.lock();
980   if (!module_sp) {
981     SymbolContextList sc_list;
982     ModuleSpec module_spec;
983     module_spec.GetFileSpec().GetFilename().SetCString(
984         "libsystem_pthread.dylib");
985     ModuleList module_list;
986     if (m_process->GetTarget().GetImages().FindModules(module_spec,
987                                                        module_list)) {
988       if (module_list.GetSize() == 1) {
989         module_sp = module_list.GetModuleAtIndex(0);
990         if (module_sp)
991           m_libpthread_module_wp = module_sp;
992       }
993     }
994   }
995   return module_sp;
996 }
997 
998 Address DynamicLoaderDarwin::GetPthreadSetSpecificAddress() {
999   if (!m_pthread_getspecific_addr.IsValid()) {
1000     ModuleSP module_sp = GetPThreadLibraryModule();
1001     if (module_sp) {
1002       lldb_private::SymbolContextList sc_list;
1003       module_sp->FindSymbolsWithNameAndType(ConstString("pthread_getspecific"),
1004                                             eSymbolTypeCode, sc_list);
1005       SymbolContext sc;
1006       if (sc_list.GetContextAtIndex(0, sc)) {
1007         if (sc.symbol)
1008           m_pthread_getspecific_addr = sc.symbol->GetAddress();
1009       }
1010     }
1011   }
1012   return m_pthread_getspecific_addr;
1013 }
1014 
1015 lldb::addr_t
1016 DynamicLoaderDarwin::GetThreadLocalData(const lldb::ModuleSP module_sp,
1017                                         const lldb::ThreadSP thread_sp,
1018                                         lldb::addr_t tls_file_addr) {
1019   if (!thread_sp || !module_sp)
1020     return LLDB_INVALID_ADDRESS;
1021 
1022   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1023 
1024   const uint32_t addr_size = m_process->GetAddressByteSize();
1025   uint8_t buf[sizeof(lldb::addr_t) * 3];
1026 
1027   lldb_private::Address tls_addr;
1028   if (module_sp->ResolveFileAddress(tls_file_addr, tls_addr)) {
1029     Status error;
1030     const size_t tsl_data_size = addr_size * 3;
1031     Target &target = m_process->GetTarget();
1032     if (target.ReadMemory(tls_addr, false, buf, tsl_data_size, error) ==
1033         tsl_data_size) {
1034       const ByteOrder byte_order = m_process->GetByteOrder();
1035       DataExtractor data(buf, sizeof(buf), byte_order, addr_size);
1036       lldb::offset_t offset = addr_size; // Skip the first pointer
1037       const lldb::addr_t pthread_key = data.GetAddress(&offset);
1038       const lldb::addr_t tls_offset = data.GetAddress(&offset);
1039       if (pthread_key != 0) {
1040         // First check to see if we have already figured out the location of
1041         // TLS data for the pthread_key on a specific thread yet. If we have we
1042         // can re-use it since its location will not change unless the process
1043         // execs.
1044         const tid_t tid = thread_sp->GetID();
1045         auto tid_pos = m_tid_to_tls_map.find(tid);
1046         if (tid_pos != m_tid_to_tls_map.end()) {
1047           auto tls_pos = tid_pos->second.find(pthread_key);
1048           if (tls_pos != tid_pos->second.end()) {
1049             return tls_pos->second + tls_offset;
1050           }
1051         }
1052         StackFrameSP frame_sp = thread_sp->GetStackFrameAtIndex(0);
1053         if (frame_sp) {
1054           ClangASTContext *clang_ast_context =
1055               target.GetScratchClangASTContext();
1056 
1057           if (!clang_ast_context)
1058             return LLDB_INVALID_ADDRESS;
1059 
1060           CompilerType clang_void_ptr_type =
1061               clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType();
1062           Address pthread_getspecific_addr = GetPthreadSetSpecificAddress();
1063           if (pthread_getspecific_addr.IsValid()) {
1064             EvaluateExpressionOptions options;
1065 
1066             lldb::ThreadPlanSP thread_plan_sp(new ThreadPlanCallFunction(
1067                 *thread_sp, pthread_getspecific_addr, clang_void_ptr_type,
1068                 llvm::ArrayRef<lldb::addr_t>(pthread_key), options));
1069 
1070             DiagnosticManager execution_errors;
1071             ExecutionContext exe_ctx(thread_sp);
1072             lldb::ExpressionResults results = m_process->RunThreadPlan(
1073                 exe_ctx, thread_plan_sp, options, execution_errors);
1074 
1075             if (results == lldb::eExpressionCompleted) {
1076               lldb::ValueObjectSP result_valobj_sp =
1077                   thread_plan_sp->GetReturnValueObject();
1078               if (result_valobj_sp) {
1079                 const lldb::addr_t pthread_key_data =
1080                     result_valobj_sp->GetValueAsUnsigned(0);
1081                 if (pthread_key_data) {
1082                   m_tid_to_tls_map[tid].insert(
1083                       std::make_pair(pthread_key, pthread_key_data));
1084                   return pthread_key_data + tls_offset;
1085                 }
1086               }
1087             }
1088           }
1089         }
1090       }
1091     }
1092   }
1093   return LLDB_INVALID_ADDRESS;
1094 }
1095 
1096 bool DynamicLoaderDarwin::UseDYLDSPI(Process *process) {
1097   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
1098   bool use_new_spi_interface = false;
1099 
1100   llvm::VersionTuple version = process->GetHostOSVersion();
1101   if (!version.empty()) {
1102     const llvm::Triple::OSType os_type =
1103         process->GetTarget().GetArchitecture().GetTriple().getOS();
1104 
1105     // macOS 10.12 and newer
1106     if (os_type == llvm::Triple::MacOSX &&
1107         version >= llvm::VersionTuple(10, 12))
1108       use_new_spi_interface = true;
1109 
1110     // iOS 10 and newer
1111     if (os_type == llvm::Triple::IOS && version >= llvm::VersionTuple(10))
1112       use_new_spi_interface = true;
1113 
1114     // tvOS 10 and newer
1115     if (os_type == llvm::Triple::TvOS && version >= llvm::VersionTuple(10))
1116       use_new_spi_interface = true;
1117 
1118     // watchOS 3 and newer
1119     if (os_type == llvm::Triple::WatchOS && version >= llvm::VersionTuple(3))
1120       use_new_spi_interface = true;
1121 
1122     // NEED_BRIDGEOS_TRIPLE // Any BridgeOS
1123     // NEED_BRIDGEOS_TRIPLE if (os_type == llvm::Triple::BridgeOS)
1124     // NEED_BRIDGEOS_TRIPLE   use_new_spi_interface = true;
1125   }
1126 
1127   if (log) {
1128     if (use_new_spi_interface)
1129       log->Printf(
1130           "DynamicLoaderDarwin::UseDYLDSPI: Use new DynamicLoader plugin");
1131     else
1132       log->Printf(
1133           "DynamicLoaderDarwin::UseDYLDSPI: Use old DynamicLoader plugin");
1134   }
1135   return use_new_spi_interface;
1136 }
1137