1 //===-- ProcessMinidump.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 // Project includes
11 #include "ProcessMinidump.h"
12 #include "ThreadMinidump.h"
13 
14 // Other libraries and framework includes
15 #include "lldb/Core/DataBufferHeap.h"
16 #include "lldb/Core/Log.h"
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/ModuleSpec.h"
19 #include "lldb/Core/PluginManager.h"
20 #include "lldb/Core/Section.h"
21 #include "lldb/Core/State.h"
22 #include "lldb/Target/DynamicLoader.h"
23 #include "lldb/Target/MemoryRegionInfo.h"
24 #include "lldb/Target/Target.h"
25 #include "lldb/Target/UnixSignals.h"
26 #include "lldb/Utility/LLDBAssert.h"
27 
28 // C includes
29 // C++ includes
30 
31 using namespace lldb_private;
32 using namespace minidump;
33 
34 ConstString ProcessMinidump::GetPluginNameStatic() {
35   static ConstString g_name("minidump");
36   return g_name;
37 }
38 
39 const char *ProcessMinidump::GetPluginDescriptionStatic() {
40   return "Minidump plug-in.";
41 }
42 
43 lldb::ProcessSP ProcessMinidump::CreateInstance(lldb::TargetSP target_sp,
44                                                 lldb::ListenerSP listener_sp,
45                                                 const FileSpec *crash_file) {
46   if (!crash_file)
47     return nullptr;
48 
49   lldb::ProcessSP process_sp;
50   // Read enough data for the Minidump header
51   const size_t header_size = sizeof(MinidumpHeader);
52   lldb::DataBufferSP data_sp(crash_file->MemoryMapFileContents(0, header_size));
53   if (!data_sp)
54     return nullptr;
55 
56   // first, only try to parse the header, beacuse we need to be fast
57   llvm::ArrayRef<uint8_t> header_data(data_sp->GetBytes(), header_size);
58   const MinidumpHeader *header = MinidumpHeader::Parse(header_data);
59 
60   if (data_sp->GetByteSize() != header_size || header == nullptr)
61     return nullptr;
62 
63   lldb::DataBufferSP all_data_sp(crash_file->MemoryMapFileContents());
64   auto minidump_parser = MinidumpParser::Create(all_data_sp);
65   // check if the parser object is valid
66   if (!minidump_parser)
67     return nullptr;
68 
69   return std::make_shared<ProcessMinidump>(target_sp, listener_sp, *crash_file,
70                                            minidump_parser.getValue());
71 }
72 
73 bool ProcessMinidump::CanDebug(lldb::TargetSP target_sp,
74                                bool plugin_specified_by_name) {
75   return true;
76 }
77 
78 ProcessMinidump::ProcessMinidump(lldb::TargetSP target_sp,
79                                  lldb::ListenerSP listener_sp,
80                                  const FileSpec &core_file,
81                                  MinidumpParser minidump_parser)
82     : Process(target_sp, listener_sp), m_minidump_parser(minidump_parser),
83       m_core_file(core_file), m_is_wow64(false) {}
84 
85 ProcessMinidump::~ProcessMinidump() {
86   Clear();
87   // We need to call finalize on the process before destroying ourselves
88   // to make sure all of the broadcaster cleanup goes as planned. If we
89   // destruct this class, then Process::~Process() might have problems
90   // trying to fully destroy the broadcaster.
91   Finalize();
92 }
93 
94 void ProcessMinidump::Initialize() {
95   static std::once_flag g_once_flag;
96 
97   std::call_once(g_once_flag, []() {
98     PluginManager::RegisterPlugin(GetPluginNameStatic(),
99                                   GetPluginDescriptionStatic(),
100                                   ProcessMinidump::CreateInstance);
101   });
102 }
103 
104 void ProcessMinidump::Terminate() {
105   PluginManager::UnregisterPlugin(ProcessMinidump::CreateInstance);
106 }
107 
108 Error ProcessMinidump::DoLoadCore() {
109   Error error;
110 
111   m_thread_list = m_minidump_parser.GetThreads();
112   m_active_exception = m_minidump_parser.GetExceptionStream();
113   ReadModuleList();
114   GetTarget().SetArchitecture(GetArchitecture());
115 
116   llvm::Optional<lldb::pid_t> pid = m_minidump_parser.GetPid();
117   if (!pid) {
118     error.SetErrorString("failed to parse PID");
119     return error;
120   }
121   SetID(pid.getValue());
122 
123   return error;
124 }
125 
126 DynamicLoader *ProcessMinidump::GetDynamicLoader() {
127   if (m_dyld_ap.get() == nullptr)
128     m_dyld_ap.reset(DynamicLoader::FindPlugin(this, nullptr));
129   return m_dyld_ap.get();
130 }
131 
132 ConstString ProcessMinidump::GetPluginName() { return GetPluginNameStatic(); }
133 
134 uint32_t ProcessMinidump::GetPluginVersion() { return 1; }
135 
136 Error ProcessMinidump::DoDestroy() { return Error(); }
137 
138 void ProcessMinidump::RefreshStateAfterStop() {
139   if (!m_active_exception)
140     return;
141 
142   if (m_active_exception->exception_record.exception_code ==
143       MinidumpException::DumpRequested) {
144     return;
145   }
146 
147   lldb::StopInfoSP stop_info;
148   lldb::ThreadSP stop_thread;
149 
150   Process::m_thread_list.SetSelectedThreadByID(m_active_exception->thread_id);
151   stop_thread = Process::m_thread_list.GetSelectedThread();
152   ArchSpec arch = GetArchitecture();
153 
154   if (arch.GetTriple().getOS() == llvm::Triple::Linux) {
155     stop_info = StopInfo::CreateStopReasonWithSignal(
156         *stop_thread, m_active_exception->exception_record.exception_code);
157   } else {
158     std::string desc;
159     llvm::raw_string_ostream desc_stream(desc);
160     desc_stream << "Exception "
161                 << llvm::format_hex(
162                        m_active_exception->exception_record.exception_code, 8)
163                 << " encountered at address "
164                 << llvm::format_hex(
165                        m_active_exception->exception_record.exception_address,
166                        8);
167     stop_info = StopInfo::CreateStopReasonWithException(
168         *stop_thread, desc_stream.str().c_str());
169   }
170 
171   stop_thread->SetStopInfo(stop_info);
172 }
173 
174 bool ProcessMinidump::IsAlive() { return true; }
175 
176 bool ProcessMinidump::WarnBeforeDetach() const { return false; }
177 
178 size_t ProcessMinidump::ReadMemory(lldb::addr_t addr, void *buf, size_t size,
179                                    Error &error) {
180   // Don't allow the caching that lldb_private::Process::ReadMemory does
181   // since we have it all cached in our dump file anyway.
182   return DoReadMemory(addr, buf, size, error);
183 }
184 
185 size_t ProcessMinidump::DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
186                                      Error &error) {
187 
188   llvm::ArrayRef<uint8_t> mem = m_minidump_parser.GetMemory(addr, size);
189   if (mem.empty()) {
190     error.SetErrorString("could not parse memory info");
191     return 0;
192   }
193 
194   std::memcpy(buf, mem.data(), mem.size());
195   return mem.size();
196 }
197 
198 ArchSpec ProcessMinidump::GetArchitecture() {
199   if (!m_is_wow64) {
200     return m_minidump_parser.GetArchitecture();
201   }
202 
203   llvm::Triple triple;
204   triple.setVendor(llvm::Triple::VendorType::UnknownVendor);
205   triple.setArch(llvm::Triple::ArchType::x86);
206   triple.setOS(llvm::Triple::OSType::Win32);
207   return ArchSpec(triple);
208 }
209 
210 Error ProcessMinidump::GetMemoryRegionInfo(lldb::addr_t load_addr,
211                                            MemoryRegionInfo &range_info) {
212   Error error;
213   auto info = m_minidump_parser.GetMemoryRegionInfo(load_addr);
214   if (!info) {
215     error.SetErrorString("No valid MemoryRegionInfo found!");
216     return error;
217   }
218   range_info = info.getValue();
219   return error;
220 }
221 
222 void ProcessMinidump::Clear() { Process::m_thread_list.Clear(); }
223 
224 bool ProcessMinidump::UpdateThreadList(ThreadList &old_thread_list,
225                                        ThreadList &new_thread_list) {
226   uint32_t num_threads = 0;
227   if (m_thread_list.size() > 0)
228     num_threads = m_thread_list.size();
229 
230   for (lldb::tid_t tid = 0; tid < num_threads; ++tid) {
231     llvm::ArrayRef<uint8_t> context;
232     if (!m_is_wow64)
233       context = m_minidump_parser.GetThreadContext(m_thread_list[tid]);
234     else
235       context = m_minidump_parser.GetThreadContextWow64(m_thread_list[tid]);
236 
237     lldb::ThreadSP thread_sp(
238         new ThreadMinidump(*this, m_thread_list[tid], context));
239     new_thread_list.AddThread(thread_sp);
240   }
241   return new_thread_list.GetSize(false) > 0;
242 }
243 
244 void ProcessMinidump::ReadModuleList() {
245   std::vector<const MinidumpModule *> filtered_modules =
246       m_minidump_parser.GetFilteredModuleList();
247 
248   for (auto module : filtered_modules) {
249     llvm::Optional<std::string> name =
250         m_minidump_parser.GetMinidumpString(module->module_name_rva);
251 
252     if (!name)
253       continue;
254 
255     Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_MODULES));
256     if (log) {
257       log->Printf("ProcessMinidump::%s found module: name: %s %#010" PRIx64
258                   "-%#010" PRIx64 " size: %" PRIu32,
259                   __FUNCTION__, name.getValue().c_str(),
260                   uint64_t(module->base_of_image),
261                   module->base_of_image + module->size_of_image,
262                   uint32_t(module->size_of_image));
263     }
264 
265     // check if the process is wow64 - a 32 bit windows process running on a
266     // 64 bit windows
267     if (llvm::StringRef(name.getValue()).endswith_lower("wow64.dll")) {
268       m_is_wow64 = true;
269     }
270 
271     const auto file_spec = FileSpec(name.getValue(), true);
272     ModuleSpec module_spec = file_spec;
273     Error error;
274     lldb::ModuleSP module_sp = GetTarget().GetSharedModule(module_spec, &error);
275     if (!module_sp || error.Fail()) {
276       continue;
277     }
278 
279     if (log) {
280       log->Printf("ProcessMinidump::%s load module: name: %s", __FUNCTION__,
281                   name.getValue().c_str());
282     }
283 
284     bool load_addr_changed = false;
285     module_sp->SetLoadAddress(GetTarget(), module->base_of_image, false,
286                               load_addr_changed);
287   }
288 }
289 
290 bool ProcessMinidump::GetProcessInfo(ProcessInstanceInfo &info) {
291   info.Clear();
292   info.SetProcessID(GetID());
293   info.SetArchitecture(GetArchitecture());
294   lldb::ModuleSP module_sp = GetTarget().GetExecutableModule();
295   if (module_sp) {
296     const bool add_exe_file_as_first_arg = false;
297     info.SetExecutableFile(GetTarget().GetExecutableModule()->GetFileSpec(),
298                            add_exe_file_as_first_arg);
299   }
300   return true;
301 }
302