LLVM  6.0.0svn
Program.inc
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1 //===- Win32/Program.cpp - Win32 Program Implementation ------- -*- 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 // This file provides the Win32 specific implementation of the Program class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "WindowsSupport.h"
15 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/Support/Errc.h"
21 #include <cstdio>
22 #include <fcntl.h>
23 #include <io.h>
24 #include <malloc.h>
25 
26 //===----------------------------------------------------------------------===//
27 //=== WARNING: Implementation here must contain only Win32 specific code
28 //=== and must not be UNIX code
29 //===----------------------------------------------------------------------===//
30 
31 namespace llvm {
32 
33 ProcessInfo::ProcessInfo() : ProcessHandle(0), Pid(0), ReturnCode(0) {}
34 
35 ErrorOr<std::string> sys::findProgramByName(StringRef Name,
36  ArrayRef<StringRef> Paths) {
37  assert(!Name.empty() && "Must have a name!");
38 
39  if (Name.find_first_of("/\\") != StringRef::npos)
40  return std::string(Name);
41 
42  const wchar_t *Path = nullptr;
43  std::wstring PathStorage;
44  if (!Paths.empty()) {
45  PathStorage.reserve(Paths.size() * MAX_PATH);
46  for (unsigned i = 0; i < Paths.size(); ++i) {
47  if (i)
48  PathStorage.push_back(L';');
49  StringRef P = Paths[i];
50  SmallVector<wchar_t, MAX_PATH> TmpPath;
51  if (std::error_code EC = windows::UTF8ToUTF16(P, TmpPath))
52  return EC;
53  PathStorage.append(TmpPath.begin(), TmpPath.end());
54  }
55  Path = PathStorage.c_str();
56  }
57 
58  SmallVector<wchar_t, MAX_PATH> U16Name;
59  if (std::error_code EC = windows::UTF8ToUTF16(Name, U16Name))
60  return EC;
61 
62  SmallVector<StringRef, 12> PathExts;
63  PathExts.push_back("");
64  PathExts.push_back(".exe"); // FIXME: This must be in %PATHEXT%.
65  if (const char *PathExtEnv = std::getenv("PATHEXT"))
66  SplitString(PathExtEnv, PathExts, ";");
67 
68  SmallVector<wchar_t, MAX_PATH> U16Result;
69  DWORD Len = MAX_PATH;
70  for (StringRef Ext : PathExts) {
71  SmallVector<wchar_t, MAX_PATH> U16Ext;
72  if (std::error_code EC = windows::UTF8ToUTF16(Ext, U16Ext))
73  return EC;
74 
75  do {
76  U16Result.reserve(Len);
77  // Lets attach the extension manually. That is needed for files
78  // with a point in name like aaa.bbb. SearchPathW will not add extension
79  // from its argument to such files because it thinks they already had one.
80  SmallVector<wchar_t, MAX_PATH> U16NameExt;
81  if (std::error_code EC =
82  windows::UTF8ToUTF16(Twine(Name + Ext).str(), U16NameExt))
83  return EC;
84 
85  Len = ::SearchPathW(Path, c_str(U16NameExt), nullptr,
86  U16Result.capacity(), U16Result.data(), nullptr);
87  } while (Len > U16Result.capacity());
88 
89  if (Len != 0)
90  break; // Found it.
91  }
92 
93  if (Len == 0)
94  return mapWindowsError(::GetLastError());
95 
96  U16Result.set_size(Len);
97 
98  SmallVector<char, MAX_PATH> U8Result;
99  if (std::error_code EC =
100  windows::UTF16ToUTF8(U16Result.data(), U16Result.size(), U8Result))
101  return EC;
102 
103  return std::string(U8Result.begin(), U8Result.end());
104 }
105 
106 static HANDLE RedirectIO(Optional<StringRef> Path, int fd,
107  std::string *ErrMsg) {
108  HANDLE h;
109  if (!Path) {
110  if (!DuplicateHandle(GetCurrentProcess(), (HANDLE)_get_osfhandle(fd),
111  GetCurrentProcess(), &h,
112  0, TRUE, DUPLICATE_SAME_ACCESS))
113  return INVALID_HANDLE_VALUE;
114  return h;
115  }
116 
117  std::string fname;
118  if (Path->empty())
119  fname = "NUL";
120  else
121  fname = *Path;
122 
123  SECURITY_ATTRIBUTES sa;
124  sa.nLength = sizeof(sa);
125  sa.lpSecurityDescriptor = 0;
126  sa.bInheritHandle = TRUE;
127 
128  SmallVector<wchar_t, 128> fnameUnicode;
129  if (Path->empty()) {
130  // Don't play long-path tricks on "NUL".
131  if (windows::UTF8ToUTF16(fname, fnameUnicode))
132  return INVALID_HANDLE_VALUE;
133  } else {
134  if (path::widenPath(fname, fnameUnicode))
135  return INVALID_HANDLE_VALUE;
136  }
137  h = CreateFileW(fnameUnicode.data(), fd ? GENERIC_WRITE : GENERIC_READ,
138  FILE_SHARE_READ, &sa, fd == 0 ? OPEN_EXISTING : CREATE_ALWAYS,
139  FILE_ATTRIBUTE_NORMAL, NULL);
140  if (h == INVALID_HANDLE_VALUE) {
141  MakeErrMsg(ErrMsg, fname + ": Can't open file for " +
142  (fd ? "input" : "output"));
143  }
144 
145  return h;
146 }
147 
148 /// ArgNeedsQuotes - Check whether argument needs to be quoted when calling
149 /// CreateProcess.
150 static bool ArgNeedsQuotes(const char *Str) {
151  return Str[0] == '\0' || strpbrk(Str, "\t \"&\'()*<>\\`^|") != 0;
152 }
153 
154 /// CountPrecedingBackslashes - Returns the number of backslashes preceding Cur
155 /// in the C string Start.
156 static unsigned int CountPrecedingBackslashes(const char *Start,
157  const char *Cur) {
158  unsigned int Count = 0;
159  --Cur;
160  while (Cur >= Start && *Cur == '\\') {
161  ++Count;
162  --Cur;
163  }
164  return Count;
165 }
166 
167 /// EscapePrecedingEscapes - Append a backslash to Dst for every backslash
168 /// preceding Cur in the Start string. Assumes Dst has enough space.
169 static char *EscapePrecedingEscapes(char *Dst, const char *Start,
170  const char *Cur) {
171  unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Cur);
172  while (PrecedingEscapes > 0) {
173  *Dst++ = '\\';
174  --PrecedingEscapes;
175  }
176  return Dst;
177 }
178 
179 /// ArgLenWithQuotes - Check whether argument needs to be quoted when calling
180 /// CreateProcess and returns length of quoted arg with escaped quotes
181 static unsigned int ArgLenWithQuotes(const char *Str) {
182  const char *Start = Str;
183  bool Quoted = ArgNeedsQuotes(Str);
184  unsigned int len = Quoted ? 2 : 0;
185 
186  while (*Str != '\0') {
187  if (*Str == '\"') {
188  // We need to add a backslash, but ensure that it isn't escaped.
189  unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
190  len += PrecedingEscapes + 1;
191  }
192  // Note that we *don't* need to escape runs of backslashes that don't
193  // precede a double quote! See MSDN:
194  // http://msdn.microsoft.com/en-us/library/17w5ykft%28v=vs.85%29.aspx
195 
196  ++len;
197  ++Str;
198  }
199 
200  if (Quoted) {
201  // Make sure the closing quote doesn't get escaped by a trailing backslash.
202  unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
203  len += PrecedingEscapes + 1;
204  }
205 
206  return len;
207 }
208 
209 }
210 
211 static std::unique_ptr<char[]> flattenArgs(const char **Args) {
212  // First, determine the length of the command line.
213  unsigned len = 0;
214  for (unsigned i = 0; Args[i]; i++) {
215  len += ArgLenWithQuotes(Args[i]) + 1;
216  }
217 
218  // Now build the command line.
219  std::unique_ptr<char[]> command(new char[len+1]);
220  char *p = command.get();
221 
222  for (unsigned i = 0; Args[i]; i++) {
223  const char *arg = Args[i];
224  const char *start = arg;
225 
226  bool needsQuoting = ArgNeedsQuotes(arg);
227  if (needsQuoting)
228  *p++ = '"';
229 
230  while (*arg != '\0') {
231  if (*arg == '\"') {
232  // Escape all preceding escapes (if any), and then escape the quote.
233  p = EscapePrecedingEscapes(p, start, arg);
234  *p++ = '\\';
235  }
236 
237  *p++ = *arg++;
238  }
239 
240  if (needsQuoting) {
241  // Make sure our quote doesn't get escaped by a trailing backslash.
242  p = EscapePrecedingEscapes(p, start, arg);
243  *p++ = '"';
244  }
245  *p++ = ' ';
246  }
247 
248  *p = 0;
249  return command;
250 }
251 
252 static bool Execute(ProcessInfo &PI, StringRef Program, const char **Args,
253  const char **Envp, ArrayRef<Optional<StringRef>> Redirects,
254  unsigned MemoryLimit, std::string *ErrMsg) {
255  if (!sys::fs::can_execute(Program)) {
256  if (ErrMsg)
257  *ErrMsg = "program not executable";
258  return false;
259  }
260 
261  // can_execute may succeed by looking at Program + ".exe". CreateProcessW
262  // will implicitly add the .exe if we provide a command line without an
263  // executable path, but since we use an explicit executable, we have to add
264  // ".exe" ourselves.
265  SmallString<64> ProgramStorage;
266  if (!sys::fs::exists(Program))
267  Program = Twine(Program + ".exe").toStringRef(ProgramStorage);
268 
269  // Windows wants a command line, not an array of args, to pass to the new
270  // process. We have to concatenate them all, while quoting the args that
271  // have embedded spaces (or are empty).
272  std::unique_ptr<char[]> command = flattenArgs(Args);
273 
274  // The pointer to the environment block for the new process.
275  std::vector<wchar_t> EnvBlock;
276 
277  if (Envp) {
278  // An environment block consists of a null-terminated block of
279  // null-terminated strings. Convert the array of environment variables to
280  // an environment block by concatenating them.
281  for (unsigned i = 0; Envp[i]; ++i) {
282  SmallVector<wchar_t, MAX_PATH> EnvString;
283  if (std::error_code ec = windows::UTF8ToUTF16(Envp[i], EnvString)) {
284  SetLastError(ec.value());
285  MakeErrMsg(ErrMsg, "Unable to convert environment variable to UTF-16");
286  return false;
287  }
288 
289  EnvBlock.insert(EnvBlock.end(), EnvString.begin(), EnvString.end());
290  EnvBlock.push_back(0);
291  }
292  EnvBlock.push_back(0);
293  }
294 
295  // Create a child process.
296  STARTUPINFOW si;
297  memset(&si, 0, sizeof(si));
298  si.cb = sizeof(si);
299  si.hStdInput = INVALID_HANDLE_VALUE;
300  si.hStdOutput = INVALID_HANDLE_VALUE;
301  si.hStdError = INVALID_HANDLE_VALUE;
302 
303  if (!Redirects.empty()) {
304  si.dwFlags = STARTF_USESTDHANDLES;
305 
306  si.hStdInput = RedirectIO(Redirects[0], 0, ErrMsg);
307  if (si.hStdInput == INVALID_HANDLE_VALUE) {
308  MakeErrMsg(ErrMsg, "can't redirect stdin");
309  return false;
310  }
311  si.hStdOutput = RedirectIO(Redirects[1], 1, ErrMsg);
312  if (si.hStdOutput == INVALID_HANDLE_VALUE) {
313  CloseHandle(si.hStdInput);
314  MakeErrMsg(ErrMsg, "can't redirect stdout");
315  return false;
316  }
317  if (Redirects[1] && Redirects[2] && *Redirects[1] == *Redirects[2]) {
318  // If stdout and stderr should go to the same place, redirect stderr
319  // to the handle already open for stdout.
320  if (!DuplicateHandle(GetCurrentProcess(), si.hStdOutput,
321  GetCurrentProcess(), &si.hStdError,
322  0, TRUE, DUPLICATE_SAME_ACCESS)) {
323  CloseHandle(si.hStdInput);
324  CloseHandle(si.hStdOutput);
325  MakeErrMsg(ErrMsg, "can't dup stderr to stdout");
326  return false;
327  }
328  } else {
329  // Just redirect stderr
330  si.hStdError = RedirectIO(Redirects[2], 2, ErrMsg);
331  if (si.hStdError == INVALID_HANDLE_VALUE) {
332  CloseHandle(si.hStdInput);
333  CloseHandle(si.hStdOutput);
334  MakeErrMsg(ErrMsg, "can't redirect stderr");
335  return false;
336  }
337  }
338  }
339 
340  PROCESS_INFORMATION pi;
341  memset(&pi, 0, sizeof(pi));
342 
343  fflush(stdout);
344  fflush(stderr);
345 
346  SmallVector<wchar_t, MAX_PATH> ProgramUtf16;
347  if (std::error_code ec = path::widenPath(Program, ProgramUtf16)) {
348  SetLastError(ec.value());
349  MakeErrMsg(ErrMsg,
350  std::string("Unable to convert application name to UTF-16"));
351  return false;
352  }
353 
354  SmallVector<wchar_t, MAX_PATH> CommandUtf16;
355  if (std::error_code ec = windows::UTF8ToUTF16(command.get(), CommandUtf16)) {
356  SetLastError(ec.value());
357  MakeErrMsg(ErrMsg,
358  std::string("Unable to convert command-line to UTF-16"));
359  return false;
360  }
361 
362  BOOL rc = CreateProcessW(ProgramUtf16.data(), CommandUtf16.data(), 0, 0,
363  TRUE, CREATE_UNICODE_ENVIRONMENT,
364  EnvBlock.empty() ? 0 : EnvBlock.data(), 0, &si,
365  &pi);
366  DWORD err = GetLastError();
367 
368  // Regardless of whether the process got created or not, we are done with
369  // the handles we created for it to inherit.
370  CloseHandle(si.hStdInput);
371  CloseHandle(si.hStdOutput);
372  CloseHandle(si.hStdError);
373 
374  // Now return an error if the process didn't get created.
375  if (!rc) {
376  SetLastError(err);
377  MakeErrMsg(ErrMsg, std::string("Couldn't execute program '") +
378  Program.str() + "'");
379  return false;
380  }
381 
382  PI.Pid = pi.dwProcessId;
383  PI.ProcessHandle = pi.hProcess;
384 
385  // Make sure these get closed no matter what.
386  ScopedCommonHandle hThread(pi.hThread);
387 
388  // Assign the process to a job if a memory limit is defined.
389  ScopedJobHandle hJob;
390  if (MemoryLimit != 0) {
391  hJob = CreateJobObjectW(0, 0);
392  bool success = false;
393  if (hJob) {
394  JOBOBJECT_EXTENDED_LIMIT_INFORMATION jeli;
395  memset(&jeli, 0, sizeof(jeli));
396  jeli.BasicLimitInformation.LimitFlags = JOB_OBJECT_LIMIT_PROCESS_MEMORY;
397  jeli.ProcessMemoryLimit = uintptr_t(MemoryLimit) * 1048576;
398  if (SetInformationJobObject(hJob, JobObjectExtendedLimitInformation,
399  &jeli, sizeof(jeli))) {
400  if (AssignProcessToJobObject(hJob, pi.hProcess))
401  success = true;
402  }
403  }
404  if (!success) {
405  SetLastError(GetLastError());
406  MakeErrMsg(ErrMsg, std::string("Unable to set memory limit"));
407  TerminateProcess(pi.hProcess, 1);
408  WaitForSingleObject(pi.hProcess, INFINITE);
409  return false;
410  }
411  }
412 
413  return true;
414 }
415 
416 namespace llvm {
417 ProcessInfo sys::Wait(const ProcessInfo &PI, unsigned SecondsToWait,
418  bool WaitUntilChildTerminates, std::string *ErrMsg) {
419  assert(PI.Pid && "invalid pid to wait on, process not started?");
420  assert(PI.ProcessHandle &&
421  "invalid process handle to wait on, process not started?");
422  DWORD milliSecondsToWait = 0;
423  if (WaitUntilChildTerminates)
424  milliSecondsToWait = INFINITE;
425  else if (SecondsToWait > 0)
426  milliSecondsToWait = SecondsToWait * 1000;
427 
428  ProcessInfo WaitResult = PI;
429  DWORD WaitStatus = WaitForSingleObject(PI.ProcessHandle, milliSecondsToWait);
430  if (WaitStatus == WAIT_TIMEOUT) {
431  if (SecondsToWait) {
432  if (!TerminateProcess(PI.ProcessHandle, 1)) {
433  if (ErrMsg)
434  MakeErrMsg(ErrMsg, "Failed to terminate timed-out program");
435 
436  // -2 indicates a crash or timeout as opposed to failure to execute.
437  WaitResult.ReturnCode = -2;
438  CloseHandle(PI.ProcessHandle);
439  return WaitResult;
440  }
441  WaitForSingleObject(PI.ProcessHandle, INFINITE);
442  CloseHandle(PI.ProcessHandle);
443  } else {
444  // Non-blocking wait.
445  return ProcessInfo();
446  }
447  }
448 
449  // Get its exit status.
450  DWORD status;
451  BOOL rc = GetExitCodeProcess(PI.ProcessHandle, &status);
452  DWORD err = GetLastError();
453  if (err != ERROR_INVALID_HANDLE)
454  CloseHandle(PI.ProcessHandle);
455 
456  if (!rc) {
457  SetLastError(err);
458  if (ErrMsg)
459  MakeErrMsg(ErrMsg, "Failed getting status for program");
460 
461  // -2 indicates a crash or timeout as opposed to failure to execute.
462  WaitResult.ReturnCode = -2;
463  return WaitResult;
464  }
465 
466  if (!status)
467  return WaitResult;
468 
469  // Pass 10(Warning) and 11(Error) to the callee as negative value.
470  if ((status & 0xBFFF0000U) == 0x80000000U)
471  WaitResult.ReturnCode = static_cast<int>(status);
472  else if (status & 0xFF)
473  WaitResult.ReturnCode = status & 0x7FFFFFFF;
474  else
475  WaitResult.ReturnCode = 1;
476 
477  return WaitResult;
478 }
479 
480 std::error_code sys::ChangeStdinToBinary() {
481  int result = _setmode(_fileno(stdin), _O_BINARY);
482  if (result == -1)
483  return std::error_code(errno, std::generic_category());
484  return std::error_code();
485 }
486 
487 std::error_code sys::ChangeStdoutToBinary() {
488  int result = _setmode(_fileno(stdout), _O_BINARY);
489  if (result == -1)
490  return std::error_code(errno, std::generic_category());
491  return std::error_code();
492 }
493 
494 std::error_code
495 llvm::sys::writeFileWithEncoding(StringRef FileName, StringRef Contents,
496  WindowsEncodingMethod Encoding) {
497  std::error_code EC;
499  if (EC)
500  return EC;
501 
502  if (Encoding == WEM_UTF8) {
503  OS << Contents;
504  } else if (Encoding == WEM_CurrentCodePage) {
505  SmallVector<wchar_t, 1> ArgsUTF16;
506  SmallVector<char, 1> ArgsCurCP;
507 
508  if ((EC = windows::UTF8ToUTF16(Contents, ArgsUTF16)))
509  return EC;
510 
511  if ((EC = windows::UTF16ToCurCP(
512  ArgsUTF16.data(), ArgsUTF16.size(), ArgsCurCP)))
513  return EC;
514 
515  OS.write(ArgsCurCP.data(), ArgsCurCP.size());
516  } else if (Encoding == WEM_UTF16) {
517  SmallVector<wchar_t, 1> ArgsUTF16;
518 
519  if ((EC = windows::UTF8ToUTF16(Contents, ArgsUTF16)))
520  return EC;
521 
522  // Endianness guessing
523  char BOM[2];
524  uint16_t src = UNI_UTF16_BYTE_ORDER_MARK_NATIVE;
525  memcpy(BOM, &src, 2);
526  OS.write(BOM, 2);
527  OS.write((char *)ArgsUTF16.data(), ArgsUTF16.size() << 1);
528  } else {
529  llvm_unreachable("Unknown encoding");
530  }
531 
532  if (OS.has_error())
534 
535  return EC;
536 }
537 
538 bool llvm::sys::commandLineFitsWithinSystemLimits(StringRef Program,
539  ArrayRef<const char *> Args) {
540  // The documented max length of the command line passed to CreateProcess.
541  static const size_t MaxCommandStringLength = 32768;
542  // Account for the trailing space for the program path and the
543  // trailing NULL of the last argument.
544  size_t ArgLength = ArgLenWithQuotes(Program.str().c_str()) + 2;
545  for (const char* Arg : Args) {
546  // Account for the trailing space for every arg
547  ArgLength += ArgLenWithQuotes(Arg) + 1;
548  if (ArgLength > MaxCommandStringLength) {
549  return false;
550  }
551  }
552  return true;
553 }
554 }
bool can_execute(const Twine &Path)
Can we execute this file?
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
std::error_code ChangeStdoutToBinary()
ErrorOr< std::string > findProgramByName(StringRef Name, ArrayRef< StringRef > Paths={})
Find the first executable file Name in Paths.
UTF-8 is the LLVM native encoding, being the same as "do not perform encoding conversion"...
Definition: Program.h:145
std::error_code make_error_code(BitcodeError E)
void SplitString(StringRef Source, SmallVectorImpl< StringRef > &OutFragments, StringRef Delimiters=" \\\)
SplitString - Split up the specified string according to the specified delimiters, appending the result fragments to the output list.
#define UNI_UTF16_BYTE_ORDER_MARK_NATIVE
Definition: ConvertUTF.h:123
#define rc(i)
#define P(N)
std::error_code status(const Twine &path, file_status &result, bool follow=true)
Get file status as if by POSIX stat().
std::error_code mapWindowsError(unsigned EV)
std::error_code UTF8ToUTF16(StringRef utf8, SmallVectorImpl< wchar_t > &utf16)
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len, SmallVectorImpl< char > &utf8)
SmallVectorImpl< T >::const_pointer c_str(SmallVectorImpl< T > &str)
std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len, SmallVectorImpl< char > &utf8)
Convert from UTF16 to the current code page used in the system.
bool commandLineFitsWithinSystemLimits(StringRef Program, ArrayRef< const char *> Args)
Return true if the given arguments fit within system-specific argument length limits.
std::error_code writeFileWithEncoding(StringRef FileName, StringRef Contents, WindowsEncodingMethod Encoding=WEM_UTF8)
Saves the UTF8-encoded contents string into the file FileName using a specific encoding.
bool MakeErrMsg(std::string *ErrMsg, const std::string &prefix)
WindowsEncodingMethod
File encoding options when writing contents that a non-UTF8 tool will read (on Windows systems)...
Definition: Program.h:142
The file should be opened in text mode on platforms that make this distinction.
Definition: FileSystem.h:683
std::error_code ChangeStdinToBinary()
amdgpu Simplify well known AMD library false Value Value * Arg
success
Parameters (see the expansion example below): (the builder, addr, loaded, new_val, ordering, /* OUT.
A raw_ostream that writes to a file descriptor.
Definition: raw_ostream.h:361
static const size_t npos
Definition: StringRef.h:51
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
ProcessInfo Wait(const ProcessInfo &PI, unsigned SecondsToWait, bool WaitUntilTerminates, std::string *ErrMsg=nullptr)
This function waits for the process specified by PI to finish.
bool exists(const basic_file_status &status)
Does file exist?
Definition: Path.cpp:962
std::error_code widenPath(const Twine &Path8, SmallVectorImpl< wchar_t > &Path16)
constexpr char Args[]
Key for Kernel::Metadata::mArgs.