xref: /freebsd/contrib/llvm-project/llvm/lib/Support/Windows/Signals.inc (revision fe75646a0234a261c0013bf1840fdac4acaf0cec) 
1//===- Win32/Signals.cpp - Win32 Signals Implementation ---------*- 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// This file provides the Win32 specific implementation of the Signals class.
10//
11//===----------------------------------------------------------------------===//
12#include "llvm/Support/ConvertUTF.h"
13#include "llvm/Support/ExitCodes.h"
14#include "llvm/Support/FileSystem.h"
15#include "llvm/Support/Path.h"
16#include "llvm/Support/Process.h"
17#include "llvm/Support/WindowsError.h"
18#include <algorithm>
19#include <io.h>
20#include <signal.h>
21#include <stdio.h>
22
23#include "llvm/Support/Format.h"
24#include "llvm/Support/raw_ostream.h"
25
26// The Windows.h header must be after LLVM and standard headers.
27#include "llvm/Support/Windows/WindowsSupport.h"
28
29#ifdef __MINGW32__
30#include <imagehlp.h>
31#else
32#include <crtdbg.h>
33#include <dbghelp.h>
34#endif
35#include <psapi.h>
36
37#ifdef _MSC_VER
38#pragma comment(lib, "psapi.lib")
39#elif __MINGW32__
40// The version of g++ that comes with MinGW does *not* properly understand
41// the ll format specifier for printf. However, MinGW passes the format
42// specifiers on to the MSVCRT entirely, and the CRT understands the ll
43// specifier. So these warnings are spurious in this case. Since we compile
44// with -Wall, this will generate these warnings which should be ignored. So
45// we will turn off the warnings for this just file. However, MinGW also does
46// not support push and pop for diagnostics, so we have to manually turn it
47// back on at the end of the file.
48#pragma GCC diagnostic ignored "-Wformat"
49#pragma GCC diagnostic ignored "-Wformat-extra-args"
50
51#if !defined(__MINGW64_VERSION_MAJOR)
52// MinGW.org does not have updated support for the 64-bit versions of the
53// DebugHlp APIs. So we will have to load them manually. The structures and
54// method signatures were pulled from DbgHelp.h in the Windows Platform SDK,
55// and adjusted for brevity.
56typedef struct _IMAGEHLP_LINE64 {
57  DWORD SizeOfStruct;
58  PVOID Key;
59  DWORD LineNumber;
60  PCHAR FileName;
61  DWORD64 Address;
62} IMAGEHLP_LINE64, *PIMAGEHLP_LINE64;
63
64typedef struct _IMAGEHLP_SYMBOL64 {
65  DWORD SizeOfStruct;
66  DWORD64 Address;
67  DWORD Size;
68  DWORD Flags;
69  DWORD MaxNameLength;
70  CHAR Name[1];
71} IMAGEHLP_SYMBOL64, *PIMAGEHLP_SYMBOL64;
72
73typedef struct _tagADDRESS64 {
74  DWORD64 Offset;
75  WORD Segment;
76  ADDRESS_MODE Mode;
77} ADDRESS64, *LPADDRESS64;
78
79typedef struct _KDHELP64 {
80  DWORD64 Thread;
81  DWORD ThCallbackStack;
82  DWORD ThCallbackBStore;
83  DWORD NextCallback;
84  DWORD FramePointer;
85  DWORD64 KiCallUserMode;
86  DWORD64 KeUserCallbackDispatcher;
87  DWORD64 SystemRangeStart;
88  DWORD64 KiUserExceptionDispatcher;
89  DWORD64 StackBase;
90  DWORD64 StackLimit;
91  DWORD64 Reserved[5];
92} KDHELP64, *PKDHELP64;
93
94typedef struct _tagSTACKFRAME64 {
95  ADDRESS64 AddrPC;
96  ADDRESS64 AddrReturn;
97  ADDRESS64 AddrFrame;
98  ADDRESS64 AddrStack;
99  ADDRESS64 AddrBStore;
100  PVOID FuncTableEntry;
101  DWORD64 Params[4];
102  BOOL Far;
103  BOOL Virtual;
104  DWORD64 Reserved[3];
105  KDHELP64 KdHelp;
106} STACKFRAME64, *LPSTACKFRAME64;
107#endif // !defined(__MINGW64_VERSION_MAJOR)
108#endif // __MINGW32__
109
110typedef BOOL(__stdcall *PREAD_PROCESS_MEMORY_ROUTINE64)(
111    HANDLE hProcess, DWORD64 qwBaseAddress, PVOID lpBuffer, DWORD nSize,
112    LPDWORD lpNumberOfBytesRead);
113
114typedef PVOID(__stdcall *PFUNCTION_TABLE_ACCESS_ROUTINE64)(HANDLE ahProcess,
115                                                           DWORD64 AddrBase);
116
117typedef DWORD64(__stdcall *PGET_MODULE_BASE_ROUTINE64)(HANDLE hProcess,
118                                                       DWORD64 Address);
119
120typedef DWORD64(__stdcall *PTRANSLATE_ADDRESS_ROUTINE64)(HANDLE hProcess,
121                                                         HANDLE hThread,
122                                                         LPADDRESS64 lpaddr);
123
124typedef BOOL(WINAPI *fpMiniDumpWriteDump)(HANDLE, DWORD, HANDLE, MINIDUMP_TYPE,
125                                          PMINIDUMP_EXCEPTION_INFORMATION,
126                                          PMINIDUMP_USER_STREAM_INFORMATION,
127                                          PMINIDUMP_CALLBACK_INFORMATION);
128static fpMiniDumpWriteDump fMiniDumpWriteDump;
129
130typedef BOOL(WINAPI *fpStackWalk64)(DWORD, HANDLE, HANDLE, LPSTACKFRAME64,
131                                    PVOID, PREAD_PROCESS_MEMORY_ROUTINE64,
132                                    PFUNCTION_TABLE_ACCESS_ROUTINE64,
133                                    PGET_MODULE_BASE_ROUTINE64,
134                                    PTRANSLATE_ADDRESS_ROUTINE64);
135static fpStackWalk64 fStackWalk64;
136
137typedef DWORD64(WINAPI *fpSymGetModuleBase64)(HANDLE, DWORD64);
138static fpSymGetModuleBase64 fSymGetModuleBase64;
139
140typedef BOOL(WINAPI *fpSymGetSymFromAddr64)(HANDLE, DWORD64, PDWORD64,
141                                            PIMAGEHLP_SYMBOL64);
142static fpSymGetSymFromAddr64 fSymGetSymFromAddr64;
143
144typedef BOOL(WINAPI *fpSymGetLineFromAddr64)(HANDLE, DWORD64, PDWORD,
145                                             PIMAGEHLP_LINE64);
146static fpSymGetLineFromAddr64 fSymGetLineFromAddr64;
147
148typedef BOOL(WINAPI *fpSymGetModuleInfo64)(HANDLE hProcess, DWORD64 dwAddr,
149                                           PIMAGEHLP_MODULE64 ModuleInfo);
150static fpSymGetModuleInfo64 fSymGetModuleInfo64;
151
152typedef PVOID(WINAPI *fpSymFunctionTableAccess64)(HANDLE, DWORD64);
153static fpSymFunctionTableAccess64 fSymFunctionTableAccess64;
154
155typedef DWORD(WINAPI *fpSymSetOptions)(DWORD);
156static fpSymSetOptions fSymSetOptions;
157
158typedef BOOL(WINAPI *fpSymInitialize)(HANDLE, PCSTR, BOOL);
159static fpSymInitialize fSymInitialize;
160
161typedef BOOL(WINAPI *fpEnumerateLoadedModules)(HANDLE,
162                                               PENUMLOADED_MODULES_CALLBACK64,
163                                               PVOID);
164static fpEnumerateLoadedModules fEnumerateLoadedModules;
165
166static bool isDebugHelpInitialized() {
167  return fStackWalk64 && fSymInitialize && fSymSetOptions && fMiniDumpWriteDump;
168}
169
170static bool load64BitDebugHelp(void) {
171  HMODULE hLib = ::LoadLibraryW(L"Dbghelp.dll");
172  if (hLib) {
173    fMiniDumpWriteDump =
174        (fpMiniDumpWriteDump)::GetProcAddress(hLib, "MiniDumpWriteDump");
175    fStackWalk64 = (fpStackWalk64)::GetProcAddress(hLib, "StackWalk64");
176    fSymGetModuleBase64 =
177        (fpSymGetModuleBase64)::GetProcAddress(hLib, "SymGetModuleBase64");
178    fSymGetSymFromAddr64 =
179        (fpSymGetSymFromAddr64)::GetProcAddress(hLib, "SymGetSymFromAddr64");
180    fSymGetLineFromAddr64 =
181        (fpSymGetLineFromAddr64)::GetProcAddress(hLib, "SymGetLineFromAddr64");
182    fSymGetModuleInfo64 =
183        (fpSymGetModuleInfo64)::GetProcAddress(hLib, "SymGetModuleInfo64");
184    fSymFunctionTableAccess64 = (fpSymFunctionTableAccess64)::GetProcAddress(
185        hLib, "SymFunctionTableAccess64");
186    fSymSetOptions = (fpSymSetOptions)::GetProcAddress(hLib, "SymSetOptions");
187    fSymInitialize = (fpSymInitialize)::GetProcAddress(hLib, "SymInitialize");
188    fEnumerateLoadedModules = (fpEnumerateLoadedModules)::GetProcAddress(
189        hLib, "EnumerateLoadedModules64");
190  }
191  return isDebugHelpInitialized();
192}
193
194using namespace llvm;
195
196// Forward declare.
197static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep);
198static BOOL WINAPI LLVMConsoleCtrlHandler(DWORD dwCtrlType);
199
200// The function to call if ctrl-c is pressed.
201static void (*InterruptFunction)() = 0;
202
203static std::vector<std::string> *FilesToRemove = NULL;
204static bool RegisteredUnhandledExceptionFilter = false;
205static bool CleanupExecuted = false;
206static PTOP_LEVEL_EXCEPTION_FILTER OldFilter = NULL;
207
208/// The function to call on "SIGPIPE" (one-time use only).
209static std::atomic<void (*)()> OneShotPipeSignalFunction(nullptr);
210
211// Windows creates a new thread to execute the console handler when an event
212// (such as CTRL/C) occurs.  This causes concurrency issues with the above
213// globals which this critical section addresses.
214static CRITICAL_SECTION CriticalSection;
215static bool CriticalSectionInitialized = false;
216
217static StringRef Argv0;
218
219enum {
220#if defined(_M_X64)
221  NativeMachineType = IMAGE_FILE_MACHINE_AMD64
222#elif defined(_M_ARM64)
223  NativeMachineType = IMAGE_FILE_MACHINE_ARM64
224#elif defined(_M_IX86)
225  NativeMachineType = IMAGE_FILE_MACHINE_I386
226#elif defined(_M_ARM)
227  NativeMachineType = IMAGE_FILE_MACHINE_ARMNT
228#else
229  NativeMachineType = IMAGE_FILE_MACHINE_UNKNOWN
230#endif
231};
232
233static bool printStackTraceWithLLVMSymbolizer(llvm::raw_ostream &OS,
234                                              HANDLE hProcess, HANDLE hThread,
235                                              STACKFRAME64 &StackFrameOrig,
236                                              CONTEXT *ContextOrig) {
237  // StackWalk64 modifies the incoming stack frame and context, so copy them.
238  STACKFRAME64 StackFrame = StackFrameOrig;
239
240  // Copy the register context so that we don't modify it while we unwind. We
241  // could use InitializeContext + CopyContext, but that's only required to get
242  // at AVX registers, which typically aren't needed by StackWalk64. Reduce the
243  // flag set to indicate that there's less data.
244  CONTEXT Context = *ContextOrig;
245  Context.ContextFlags = CONTEXT_CONTROL | CONTEXT_INTEGER;
246
247  static void *StackTrace[256];
248  size_t Depth = 0;
249  while (fStackWalk64(NativeMachineType, hProcess, hThread, &StackFrame,
250                      &Context, 0, fSymFunctionTableAccess64,
251                      fSymGetModuleBase64, 0)) {
252    if (StackFrame.AddrFrame.Offset == 0)
253      break;
254    StackTrace[Depth++] = (void *)(uintptr_t)StackFrame.AddrPC.Offset;
255    if (Depth >= std::size(StackTrace))
256      break;
257  }
258
259  return printSymbolizedStackTrace(Argv0, &StackTrace[0], Depth, OS);
260}
261
262namespace {
263struct FindModuleData {
264  void **StackTrace;
265  int Depth;
266  const char **Modules;
267  intptr_t *Offsets;
268  StringSaver *StrPool;
269};
270} // namespace
271
272static BOOL CALLBACK findModuleCallback(PCSTR ModuleName, DWORD64 ModuleBase,
273                                        ULONG ModuleSize, void *VoidData) {
274  FindModuleData *Data = (FindModuleData *)VoidData;
275  intptr_t Beg = ModuleBase;
276  intptr_t End = Beg + ModuleSize;
277  for (int I = 0; I < Data->Depth; I++) {
278    if (Data->Modules[I])
279      continue;
280    intptr_t Addr = (intptr_t)Data->StackTrace[I];
281    if (Beg <= Addr && Addr < End) {
282      Data->Modules[I] = Data->StrPool->save(ModuleName).data();
283      Data->Offsets[I] = Addr - Beg;
284    }
285  }
286  return TRUE;
287}
288
289static bool findModulesAndOffsets(void **StackTrace, int Depth,
290                                  const char **Modules, intptr_t *Offsets,
291                                  const char *MainExecutableName,
292                                  StringSaver &StrPool) {
293  if (!fEnumerateLoadedModules)
294    return false;
295  FindModuleData Data;
296  Data.StackTrace = StackTrace;
297  Data.Depth = Depth;
298  Data.Modules = Modules;
299  Data.Offsets = Offsets;
300  Data.StrPool = &StrPool;
301  fEnumerateLoadedModules(GetCurrentProcess(), findModuleCallback, &Data);
302  return true;
303}
304
305static void PrintStackTraceForThread(llvm::raw_ostream &OS, HANDLE hProcess,
306                                     HANDLE hThread, STACKFRAME64 &StackFrame,
307                                     CONTEXT *Context) {
308  // It's possible that DbgHelp.dll hasn't been loaded yet (e.g. if this
309  // function is called before the main program called `llvm::InitLLVM`).
310  // In this case just return, not stacktrace will be printed.
311  if (!isDebugHelpInitialized())
312    return;
313
314  // Initialize the symbol handler.
315  fSymSetOptions(SYMOPT_DEFERRED_LOADS | SYMOPT_LOAD_LINES);
316  fSymInitialize(hProcess, NULL, TRUE);
317
318  // Try llvm-symbolizer first. llvm-symbolizer knows how to deal with both PDBs
319  // and DWARF, so it should do a good job regardless of what debug info or
320  // linker is in use.
321  if (printStackTraceWithLLVMSymbolizer(OS, hProcess, hThread, StackFrame,
322                                        Context)) {
323    return;
324  }
325
326  while (true) {
327    if (!fStackWalk64(NativeMachineType, hProcess, hThread, &StackFrame,
328                      Context, 0, fSymFunctionTableAccess64,
329                      fSymGetModuleBase64, 0)) {
330      break;
331    }
332
333    if (StackFrame.AddrFrame.Offset == 0)
334      break;
335
336    using namespace llvm;
337    // Print the PC in hexadecimal.
338    DWORD64 PC = StackFrame.AddrPC.Offset;
339#if defined(_M_X64) || defined(_M_ARM64)
340    OS << format("0x%016llX", PC);
341#elif defined(_M_IX86) || defined(_M_ARM)
342    OS << format("0x%08lX", static_cast<DWORD>(PC));
343#endif
344
345    // Verify the PC belongs to a module in this process.
346    if (!fSymGetModuleBase64(hProcess, PC)) {
347      OS << " <unknown module>\n";
348      continue;
349    }
350
351    IMAGEHLP_MODULE64 M;
352    memset(&M, 0, sizeof(IMAGEHLP_MODULE64));
353    M.SizeOfStruct = sizeof(IMAGEHLP_MODULE64);
354    if (fSymGetModuleInfo64(hProcess, fSymGetModuleBase64(hProcess, PC), &M)) {
355      DWORD64 const disp = PC - M.BaseOfImage;
356      OS << format(", %s(0x%016llX) + 0x%llX byte(s)",
357                   static_cast<char *>(M.ImageName), M.BaseOfImage,
358                   static_cast<long long>(disp));
359    } else {
360      OS << ", <unknown module>";
361    }
362
363    // Print the symbol name.
364    char buffer[512];
365    IMAGEHLP_SYMBOL64 *symbol = reinterpret_cast<IMAGEHLP_SYMBOL64 *>(buffer);
366    memset(symbol, 0, sizeof(IMAGEHLP_SYMBOL64));
367    symbol->SizeOfStruct = sizeof(IMAGEHLP_SYMBOL64);
368    symbol->MaxNameLength = 512 - sizeof(IMAGEHLP_SYMBOL64);
369
370    DWORD64 dwDisp;
371    if (!fSymGetSymFromAddr64(hProcess, PC, &dwDisp, symbol)) {
372      OS << '\n';
373      continue;
374    }
375
376    buffer[511] = 0;
377    OS << format(", %s() + 0x%llX byte(s)", static_cast<char *>(symbol->Name),
378                 static_cast<long long>(dwDisp));
379
380    // Print the source file and line number information.
381    IMAGEHLP_LINE64 line = {};
382    DWORD dwLineDisp;
383    line.SizeOfStruct = sizeof(line);
384    if (fSymGetLineFromAddr64(hProcess, PC, &dwLineDisp, &line)) {
385      OS << format(", %s, line %lu + 0x%lX byte(s)", line.FileName,
386                   line.LineNumber, dwLineDisp);
387    }
388
389    OS << '\n';
390  }
391}
392
393namespace llvm {
394
395//===----------------------------------------------------------------------===//
396//=== WARNING: Implementation here must contain only Win32 specific code
397//===          and must not be UNIX code
398//===----------------------------------------------------------------------===//
399
400#ifdef _MSC_VER
401/// Emulates hitting "retry" from an "abort, retry, ignore" CRT debug report
402/// dialog. "retry" raises an exception which ultimately triggers our stack
403/// dumper.
404static LLVM_ATTRIBUTE_UNUSED int
405AvoidMessageBoxHook(int ReportType, char *Message, int *Return) {
406  // Set *Return to the retry code for the return value of _CrtDbgReport:
407  // http://msdn.microsoft.com/en-us/library/8hyw4sy7(v=vs.71).aspx
408  // This may also trigger just-in-time debugging via DebugBreak().
409  if (Return)
410    *Return = 1;
411  // Don't call _CrtDbgReport.
412  return TRUE;
413}
414
415#endif
416
417extern "C" void HandleAbort(int Sig) {
418  if (Sig == SIGABRT) {
419    LLVM_BUILTIN_TRAP;
420  }
421}
422
423static void InitializeThreading() {
424  if (CriticalSectionInitialized)
425    return;
426
427  // Now's the time to create the critical section. This is the first time
428  // through here, and there's only one thread.
429  InitializeCriticalSection(&CriticalSection);
430  CriticalSectionInitialized = true;
431}
432
433static void RegisterHandler() {
434  // If we cannot load up the APIs (which would be unexpected as they should
435  // exist on every version of Windows we support), we will bail out since
436  // there would be nothing to report.
437  if (!load64BitDebugHelp()) {
438    assert(false && "These APIs should always be available");
439    return;
440  }
441
442  if (RegisteredUnhandledExceptionFilter) {
443    EnterCriticalSection(&CriticalSection);
444    return;
445  }
446
447  InitializeThreading();
448
449  // Enter it immediately.  Now if someone hits CTRL/C, the console handler
450  // can't proceed until the globals are updated.
451  EnterCriticalSection(&CriticalSection);
452
453  RegisteredUnhandledExceptionFilter = true;
454  OldFilter = SetUnhandledExceptionFilter(LLVMUnhandledExceptionFilter);
455  SetConsoleCtrlHandler(LLVMConsoleCtrlHandler, TRUE);
456
457  // IMPORTANT NOTE: Caller must call LeaveCriticalSection(&CriticalSection) or
458  // else multi-threading problems will ensue.
459}
460
461// The public API
462bool sys::RemoveFileOnSignal(StringRef Filename, std::string *ErrMsg) {
463  RegisterHandler();
464
465  if (CleanupExecuted) {
466    if (ErrMsg)
467      *ErrMsg = "Process terminating -- cannot register for removal";
468    return true;
469  }
470
471  if (FilesToRemove == NULL)
472    FilesToRemove = new std::vector<std::string>;
473
474  FilesToRemove->push_back(std::string(Filename));
475
476  LeaveCriticalSection(&CriticalSection);
477  return false;
478}
479
480// The public API
481void sys::DontRemoveFileOnSignal(StringRef Filename) {
482  if (FilesToRemove == NULL)
483    return;
484
485  RegisterHandler();
486
487  std::vector<std::string>::reverse_iterator I =
488      find(reverse(*FilesToRemove), Filename);
489  if (I != FilesToRemove->rend())
490    FilesToRemove->erase(I.base() - 1);
491
492  LeaveCriticalSection(&CriticalSection);
493}
494
495void sys::DisableSystemDialogsOnCrash() {
496  // Crash to stack trace handler on abort.
497  signal(SIGABRT, HandleAbort);
498
499  // The following functions are not reliably accessible on MinGW.
500#ifdef _MSC_VER
501  // We're already handling writing a "something went wrong" message.
502  _set_abort_behavior(0, _WRITE_ABORT_MSG);
503  // Disable Dr. Watson.
504  _set_abort_behavior(0, _CALL_REPORTFAULT);
505  _CrtSetReportHook(AvoidMessageBoxHook);
506#endif
507
508  // Disable standard error dialog box.
509  SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX |
510               SEM_NOOPENFILEERRORBOX);
511  _set_error_mode(_OUT_TO_STDERR);
512}
513
514/// When an error signal (such as SIGABRT or SIGSEGV) is delivered to the
515/// process, print a stack trace and then exit.
516void sys::PrintStackTraceOnErrorSignal(StringRef Argv0,
517                                       bool DisableCrashReporting) {
518  ::Argv0 = Argv0;
519
520  if (DisableCrashReporting || getenv("LLVM_DISABLE_CRASH_REPORT"))
521    Process::PreventCoreFiles();
522
523  DisableSystemDialogsOnCrash();
524  RegisterHandler();
525  LeaveCriticalSection(&CriticalSection);
526}
527} // namespace llvm
528
529#if defined(__MINGW32__) && !defined(__MINGW64_VERSION_MAJOR)
530// Provide a prototype for RtlCaptureContext, mingw32 from mingw.org is
531// missing it but mingw-w64 has it.
532extern "C" VOID WINAPI RtlCaptureContext(PCONTEXT ContextRecord);
533#endif
534
535static void LocalPrintStackTrace(raw_ostream &OS, PCONTEXT C) {
536  STACKFRAME64 StackFrame{};
537  CONTEXT Context{};
538  if (!C) {
539    ::RtlCaptureContext(&Context);
540    C = &Context;
541  }
542#if defined(_M_X64)
543  StackFrame.AddrPC.Offset = Context.Rip;
544  StackFrame.AddrStack.Offset = Context.Rsp;
545  StackFrame.AddrFrame.Offset = Context.Rbp;
546#elif defined(_M_IX86)
547  StackFrame.AddrPC.Offset = Context.Eip;
548  StackFrame.AddrStack.Offset = Context.Esp;
549  StackFrame.AddrFrame.Offset = Context.Ebp;
550#elif defined(_M_ARM64)
551  StackFrame.AddrPC.Offset = Context.Pc;
552  StackFrame.AddrStack.Offset = Context.Sp;
553  StackFrame.AddrFrame.Offset = Context.Fp;
554#elif defined(_M_ARM)
555  StackFrame.AddrPC.Offset = Context.Pc;
556  StackFrame.AddrStack.Offset = Context.Sp;
557  StackFrame.AddrFrame.Offset = Context.R11;
558#endif
559  StackFrame.AddrPC.Mode = AddrModeFlat;
560  StackFrame.AddrStack.Mode = AddrModeFlat;
561  StackFrame.AddrFrame.Mode = AddrModeFlat;
562  PrintStackTraceForThread(OS, GetCurrentProcess(), GetCurrentThread(),
563                           StackFrame, C);
564}
565
566void llvm::sys::PrintStackTrace(raw_ostream &OS, int Depth) {
567  // FIXME: Handle "Depth" parameter to print stack trace upto specified Depth
568  LocalPrintStackTrace(OS, nullptr);
569}
570
571void llvm::sys::SetInterruptFunction(void (*IF)()) {
572  RegisterHandler();
573  InterruptFunction = IF;
574  LeaveCriticalSection(&CriticalSection);
575}
576
577void llvm::sys::SetInfoSignalFunction(void (*Handler)()) {
578  // Unimplemented.
579}
580
581void llvm::sys::SetOneShotPipeSignalFunction(void (*Handler)()) {
582  OneShotPipeSignalFunction.exchange(Handler);
583}
584
585void llvm::sys::DefaultOneShotPipeSignalHandler() {
586  llvm::sys::Process::Exit(EX_IOERR, /*NoCleanup=*/true);
587}
588
589void llvm::sys::CallOneShotPipeSignalHandler() {
590  if (auto OldOneShotPipeFunction = OneShotPipeSignalFunction.exchange(nullptr))
591    OldOneShotPipeFunction();
592}
593
594/// Add a function to be called when a signal is delivered to the process. The
595/// handler can have a cookie passed to it to identify what instance of the
596/// handler it is.
597void llvm::sys::AddSignalHandler(sys::SignalHandlerCallback FnPtr,
598                                 void *Cookie) {
599  insertSignalHandler(FnPtr, Cookie);
600  RegisterHandler();
601  LeaveCriticalSection(&CriticalSection);
602}
603
604static void Cleanup(bool ExecuteSignalHandlers) {
605  if (CleanupExecuted)
606    return;
607
608  EnterCriticalSection(&CriticalSection);
609
610  // Prevent other thread from registering new files and directories for
611  // removal, should we be executing because of the console handler callback.
612  CleanupExecuted = true;
613
614  // FIXME: open files cannot be deleted.
615  if (FilesToRemove != NULL)
616    while (!FilesToRemove->empty()) {
617      llvm::sys::fs::remove(FilesToRemove->back());
618      FilesToRemove->pop_back();
619    }
620
621  if (ExecuteSignalHandlers)
622    llvm::sys::RunSignalHandlers();
623
624  LeaveCriticalSection(&CriticalSection);
625}
626
627void llvm::sys::RunInterruptHandlers() {
628  // The interrupt handler may be called from an interrupt, but it may also be
629  // called manually (such as the case of report_fatal_error with no registered
630  // error handler). We must ensure that the critical section is properly
631  // initialized.
632  InitializeThreading();
633  Cleanup(true);
634}
635
636/// Find the Windows Registry Key for a given location.
637///
638/// \returns a valid HKEY if the location exists, else NULL.
639static HKEY FindWERKey(const llvm::Twine &RegistryLocation) {
640  HKEY Key;
641  if (ERROR_SUCCESS != ::RegOpenKeyExA(HKEY_LOCAL_MACHINE,
642                                       RegistryLocation.str().c_str(), 0,
643                                       KEY_QUERY_VALUE | KEY_READ, &Key))
644    return NULL;
645
646  return Key;
647}
648
649/// Populate ResultDirectory with the value for "DumpFolder" for a given
650/// Windows Registry key.
651///
652/// \returns true if a valid value for DumpFolder exists, false otherwise.
653static bool GetDumpFolder(HKEY Key,
654                          llvm::SmallVectorImpl<char> &ResultDirectory) {
655  using llvm::sys::windows::UTF16ToUTF8;
656
657  if (!Key)
658    return false;
659
660  DWORD BufferLengthBytes = 0;
661
662  if (ERROR_SUCCESS != ::RegGetValueW(Key, 0, L"DumpFolder", REG_EXPAND_SZ,
663                                      NULL, NULL, &BufferLengthBytes))
664    return false;
665
666  SmallVector<wchar_t, MAX_PATH> Buffer(BufferLengthBytes);
667
668  if (ERROR_SUCCESS != ::RegGetValueW(Key, 0, L"DumpFolder", REG_EXPAND_SZ,
669                                      NULL, Buffer.data(), &BufferLengthBytes))
670    return false;
671
672  DWORD ExpandBufferSize = ::ExpandEnvironmentStringsW(Buffer.data(), NULL, 0);
673
674  if (!ExpandBufferSize)
675    return false;
676
677  SmallVector<wchar_t, MAX_PATH> ExpandBuffer(ExpandBufferSize);
678
679  if (ExpandBufferSize != ::ExpandEnvironmentStringsW(Buffer.data(),
680                                                      ExpandBuffer.data(),
681                                                      ExpandBufferSize))
682    return false;
683
684  if (UTF16ToUTF8(ExpandBuffer.data(), ExpandBufferSize - 1, ResultDirectory))
685    return false;
686
687  return true;
688}
689
690/// Populate ResultType with a valid MINIDUMP_TYPE based on the value of
691/// "DumpType" for a given Windows Registry key.
692///
693/// According to
694/// https://msdn.microsoft.com/en-us/library/windows/desktop/bb787181(v=vs.85).aspx
695/// valid values for DumpType are:
696///   * 0: Custom dump
697///   * 1: Mini dump
698///   * 2: Full dump
699/// If "Custom dump" is specified then the "CustomDumpFlags" field is read
700/// containing a bitwise combination of MINIDUMP_TYPE values.
701///
702/// \returns true if a valid value for ResultType can be set, false otherwise.
703static bool GetDumpType(HKEY Key, MINIDUMP_TYPE &ResultType) {
704  if (!Key)
705    return false;
706
707  DWORD DumpType;
708  DWORD TypeSize = sizeof(DumpType);
709  if (ERROR_SUCCESS != ::RegGetValueW(Key, NULL, L"DumpType", RRF_RT_REG_DWORD,
710                                      NULL, &DumpType, &TypeSize))
711    return false;
712
713  switch (DumpType) {
714  case 0: {
715    DWORD Flags = 0;
716    if (ERROR_SUCCESS != ::RegGetValueW(Key, NULL, L"CustomDumpFlags",
717                                        RRF_RT_REG_DWORD, NULL, &Flags,
718                                        &TypeSize))
719      return false;
720
721    ResultType = static_cast<MINIDUMP_TYPE>(Flags);
722    break;
723  }
724  case 1:
725    ResultType = MiniDumpNormal;
726    break;
727  case 2:
728    ResultType = MiniDumpWithFullMemory;
729    break;
730  default:
731    return false;
732  }
733  return true;
734}
735
736/// Write a Windows dump file containing process information that can be
737/// used for post-mortem debugging.
738///
739/// \returns zero error code if a mini dump created, actual error code
740/// otherwise.
741static std::error_code WINAPI
742WriteWindowsDumpFile(PMINIDUMP_EXCEPTION_INFORMATION ExceptionInfo) {
743  struct ScopedCriticalSection {
744    ScopedCriticalSection() { EnterCriticalSection(&CriticalSection); }
745    ~ScopedCriticalSection() { LeaveCriticalSection(&CriticalSection); }
746  } SCS;
747
748  using namespace llvm;
749  using namespace llvm::sys;
750
751  std::string MainExecutableName = fs::getMainExecutable(nullptr, nullptr);
752  StringRef ProgramName;
753
754  if (MainExecutableName.empty()) {
755    // If we can't get the executable filename,
756    // things are in worse shape than we realize
757    // and we should just bail out.
758    return mapWindowsError(::GetLastError());
759  }
760
761  ProgramName = path::filename(MainExecutableName.c_str());
762
763  // The Windows Registry location as specified at
764  // https://msdn.microsoft.com/en-us/library/windows/desktop/bb787181%28v=vs.85%29.aspx
765  // "Collecting User-Mode Dumps" that may optionally be set to collect crash
766  // dumps in a specified location.
767  StringRef LocalDumpsRegistryLocation =
768      "SOFTWARE\\Microsoft\\Windows\\Windows Error Reporting\\LocalDumps";
769
770  // The key pointing to the Registry location that may contain global crash
771  // dump settings.  This will be NULL if the location can not be found.
772  ScopedRegHandle DefaultLocalDumpsKey(FindWERKey(LocalDumpsRegistryLocation));
773
774  // The key pointing to the Registry location that may contain
775  // application-specific crash dump settings.  This will be NULL if the
776  // location can not be found.
777  ScopedRegHandle AppSpecificKey(
778      FindWERKey(Twine(LocalDumpsRegistryLocation) + "\\" + ProgramName));
779
780  // Look to see if a dump type is specified in the registry; first with the
781  // app-specific key and failing that with the global key.  If none are found
782  // default to a normal dump (GetDumpType will return false either if the key
783  // is NULL or if there is no valid DumpType value at its location).
784  MINIDUMP_TYPE DumpType;
785  if (!GetDumpType(AppSpecificKey, DumpType))
786    if (!GetDumpType(DefaultLocalDumpsKey, DumpType))
787      DumpType = MiniDumpNormal;
788
789  // Look to see if a dump location is specified on the command line.  If not,
790  // look to see if a dump location is specified in the registry; first with the
791  // app-specific key and failing that with the global key.  If none are found
792  // we'll just create the dump file in the default temporary file location
793  // (GetDumpFolder will return false either if the key is NULL or if there is
794  // no valid DumpFolder value at its location).
795  bool ExplicitDumpDirectorySet = true;
796  SmallString<MAX_PATH> DumpDirectory(*CrashDiagnosticsDirectory);
797  if (DumpDirectory.empty())
798    if (!GetDumpFolder(AppSpecificKey, DumpDirectory))
799      if (!GetDumpFolder(DefaultLocalDumpsKey, DumpDirectory))
800        ExplicitDumpDirectorySet = false;
801
802  int FD;
803  SmallString<MAX_PATH> DumpPath;
804
805  if (ExplicitDumpDirectorySet) {
806    if (std::error_code EC = fs::create_directories(DumpDirectory))
807      return EC;
808    if (std::error_code EC = fs::createUniqueFile(
809            Twine(DumpDirectory) + "\\" + ProgramName + ".%%%%%%.dmp", FD,
810            DumpPath))
811      return EC;
812  } else if (std::error_code EC =
813                 fs::createTemporaryFile(ProgramName, "dmp", FD, DumpPath))
814    return EC;
815
816  // Our support functions return a file descriptor but Windows wants a handle.
817  ScopedCommonHandle FileHandle(reinterpret_cast<HANDLE>(_get_osfhandle(FD)));
818
819  if (!fMiniDumpWriteDump(::GetCurrentProcess(), ::GetCurrentProcessId(),
820                          FileHandle, DumpType, ExceptionInfo, NULL, NULL))
821    return mapWindowsError(::GetLastError());
822
823  llvm::errs() << "Wrote crash dump file \"" << DumpPath << "\"\n";
824  return std::error_code();
825}
826
827void sys::CleanupOnSignal(uintptr_t Context) {
828  LPEXCEPTION_POINTERS EP = (LPEXCEPTION_POINTERS)Context;
829  // Broken pipe is not a crash.
830  //
831  // 0xE0000000 is combined with the return code in the exception raised in
832  // CrashRecoveryContext::HandleExit().
833  unsigned RetCode = EP->ExceptionRecord->ExceptionCode;
834  if (RetCode == (0xE0000000 | EX_IOERR))
835    return;
836  LLVMUnhandledExceptionFilter(EP);
837}
838
839static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep) {
840  Cleanup(true);
841
842  // Write out the exception code.
843  if (ep && ep->ExceptionRecord)
844    llvm::errs() << format("Exception Code: 0x%08X",
845                           ep->ExceptionRecord->ExceptionCode)
846                 << "\n";
847
848  // We'll automatically write a Minidump file here to help diagnose
849  // the nasty sorts of crashes that aren't 100% reproducible from a set of
850  // inputs (or in the event that the user is unable or unwilling to provide a
851  // reproducible case).
852  if (!llvm::sys::Process::AreCoreFilesPrevented()) {
853    MINIDUMP_EXCEPTION_INFORMATION ExceptionInfo;
854    ExceptionInfo.ThreadId = ::GetCurrentThreadId();
855    ExceptionInfo.ExceptionPointers = ep;
856    ExceptionInfo.ClientPointers = FALSE;
857
858    if (std::error_code EC = WriteWindowsDumpFile(&ExceptionInfo))
859      llvm::errs() << "Could not write crash dump file: " << EC.message()
860                   << "\n";
861  }
862
863  // Stack unwinding appears to modify the context. Copy it to preserve the
864  // caller's context.
865  CONTEXT ContextCopy;
866  if (ep)
867    memcpy(&ContextCopy, ep->ContextRecord, sizeof(ContextCopy));
868
869  LocalPrintStackTrace(llvm::errs(), ep ? &ContextCopy : nullptr);
870
871  return EXCEPTION_EXECUTE_HANDLER;
872}
873
874static BOOL WINAPI LLVMConsoleCtrlHandler(DWORD dwCtrlType) {
875  // We are running in our very own thread, courtesy of Windows.
876  EnterCriticalSection(&CriticalSection);
877  // This function is only ever called when a CTRL-C or similar control signal
878  // is fired. Killing a process in this way is normal, so don't trigger the
879  // signal handlers.
880  Cleanup(false);
881
882  // If an interrupt function has been set, go and run one it; otherwise,
883  // the process dies.
884  void (*IF)() = InterruptFunction;
885  InterruptFunction = 0; // Don't run it on another CTRL-C.
886
887  if (IF) {
888    // Note: if the interrupt function throws an exception, there is nothing
889    // to catch it in this thread so it will kill the process.
890    IF(); // Run it now.
891    LeaveCriticalSection(&CriticalSection);
892    return TRUE; // Don't kill the process.
893  }
894
895  // Allow normal processing to take place; i.e., the process dies.
896  LeaveCriticalSection(&CriticalSection);
897  return FALSE;
898}
899
900#if __MINGW32__
901// We turned these warnings off for this file so that MinGW-g++ doesn't
902// complain about the ll format specifiers used.  Now we are turning the
903// warnings back on.  If MinGW starts to support diagnostic stacks, we can
904// replace this with a pop.
905#pragma GCC diagnostic warning "-Wformat"
906#pragma GCC diagnostic warning "-Wformat-extra-args"
907#endif
908
909void sys::unregisterHandlers() {}
910