Program.inc revision ae06a63be5a1279739e0c8a2006e72f4bc687d57 
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 "Windows.h"
15#include "llvm/ADT/OwningPtr.h"
16#include "llvm/Support/FileSystem.h"
17#include <cstdio>
18#include <fcntl.h>
19#include <io.h>
20#include <malloc.h>
21
22//===----------------------------------------------------------------------===//
23//=== WARNING: Implementation here must contain only Win32 specific code
24//===          and must not be UNIX code
25//===----------------------------------------------------------------------===//
26
27namespace llvm {
28using namespace sys;
29
30ProcessInfo::ProcessInfo() : Pid(0), ProcessHandle(0), ReturnCode(0) {}
31
32// This function just uses the PATH environment variable to find the program.
33std::string sys::FindProgramByName(const std::string &progName) {
34  // Check some degenerate cases
35  if (progName.length() == 0) // no program
36    return "";
37  std::string temp = progName;
38  // Return paths with slashes verbatim.
39  if (progName.find('\\') != std::string::npos ||
40      progName.find('/') != std::string::npos)
41    return temp;
42
43  // At this point, the file name is valid and does not contain slashes.
44  // Let Windows search for it.
45  SmallVector<wchar_t, MAX_PATH> progNameUnicode;
46  if (windows::UTF8ToUTF16(progName, progNameUnicode))
47    return "";
48
49  SmallVector<wchar_t, MAX_PATH> buffer;
50  DWORD len = MAX_PATH;
51  do {
52    buffer.reserve(len);
53    len = ::SearchPathW(NULL, progNameUnicode.data(), L".exe",
54                        buffer.capacity(), buffer.data(), NULL);
55
56    // See if it wasn't found.
57    if (len == 0)
58      return "";
59
60    // Buffer was too small; grow and retry.
61  } while (len > buffer.capacity());
62
63  buffer.set_size(len);
64  SmallVector<char, MAX_PATH> result;
65  if (windows::UTF16ToUTF8(buffer.begin(), buffer.size(), result))
66    return "";
67
68  return std::string(result.data(), result.size());
69}
70
71static HANDLE RedirectIO(const StringRef *path, int fd, std::string* ErrMsg) {
72  HANDLE h;
73  if (path == 0) {
74    if (!DuplicateHandle(GetCurrentProcess(), (HANDLE)_get_osfhandle(fd),
75                         GetCurrentProcess(), &h,
76                         0, TRUE, DUPLICATE_SAME_ACCESS))
77      return INVALID_HANDLE_VALUE;
78    return h;
79  }
80
81  std::string fname;
82  if (path->empty())
83    fname = "NUL";
84  else
85    fname = *path;
86
87  SECURITY_ATTRIBUTES sa;
88  sa.nLength = sizeof(sa);
89  sa.lpSecurityDescriptor = 0;
90  sa.bInheritHandle = TRUE;
91
92  SmallVector<wchar_t, 128> fnameUnicode;
93  if (windows::UTF8ToUTF16(fname, fnameUnicode))
94    return INVALID_HANDLE_VALUE;
95
96  h = CreateFileW(fnameUnicode.data(), fd ? GENERIC_WRITE : GENERIC_READ,
97                  FILE_SHARE_READ, &sa, fd == 0 ? OPEN_EXISTING : CREATE_ALWAYS,
98                  FILE_ATTRIBUTE_NORMAL, NULL);
99  if (h == INVALID_HANDLE_VALUE) {
100    MakeErrMsg(ErrMsg, std::string(fname) + ": Can't open file for " +
101        (fd ? "input: " : "output: "));
102  }
103
104  return h;
105}
106
107/// ArgNeedsQuotes - Check whether argument needs to be quoted when calling
108/// CreateProcess.
109static bool ArgNeedsQuotes(const char *Str) {
110  return Str[0] == '\0' || strpbrk(Str, "\t \"&\'()*<>\\`^|") != 0;
111}
112
113/// CountPrecedingBackslashes - Returns the number of backslashes preceding Cur
114/// in the C string Start.
115static unsigned int CountPrecedingBackslashes(const char *Start,
116                                              const char *Cur) {
117  unsigned int Count = 0;
118  --Cur;
119  while (Cur >= Start && *Cur == '\\') {
120    ++Count;
121    --Cur;
122  }
123  return Count;
124}
125
126/// EscapePrecedingEscapes - Append a backslash to Dst for every backslash
127/// preceding Cur in the Start string.  Assumes Dst has enough space.
128static char *EscapePrecedingEscapes(char *Dst, const char *Start,
129                                    const char *Cur) {
130  unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Cur);
131  while (PrecedingEscapes > 0) {
132    *Dst++ = '\\';
133    --PrecedingEscapes;
134  }
135  return Dst;
136}
137
138/// ArgLenWithQuotes - Check whether argument needs to be quoted when calling
139/// CreateProcess and returns length of quoted arg with escaped quotes
140static unsigned int ArgLenWithQuotes(const char *Str) {
141  const char *Start = Str;
142  bool Quoted = ArgNeedsQuotes(Str);
143  unsigned int len = Quoted ? 2 : 0;
144
145  while (*Str != '\0') {
146    if (*Str == '\"') {
147      // We need to add a backslash, but ensure that it isn't escaped.
148      unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
149      len += PrecedingEscapes + 1;
150    }
151    // Note that we *don't* need to escape runs of backslashes that don't
152    // precede a double quote!  See MSDN:
153    // http://msdn.microsoft.com/en-us/library/17w5ykft%28v=vs.85%29.aspx
154
155    ++len;
156    ++Str;
157  }
158
159  if (Quoted) {
160    // Make sure the closing quote doesn't get escaped by a trailing backslash.
161    unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
162    len += PrecedingEscapes + 1;
163  }
164
165  return len;
166}
167
168}
169
170static bool Execute(ProcessInfo &PI, StringRef Program, const char **args,
171                    const char **envp, const StringRef **redirects,
172                    unsigned memoryLimit, std::string *ErrMsg) {
173  if (!sys::fs::can_execute(Program)) {
174    if (ErrMsg)
175      *ErrMsg = "program not executable";
176    return false;
177  }
178
179  // Windows wants a command line, not an array of args, to pass to the new
180  // process.  We have to concatenate them all, while quoting the args that
181  // have embedded spaces (or are empty).
182
183  // First, determine the length of the command line.
184  unsigned len = 0;
185  for (unsigned i = 0; args[i]; i++) {
186    len += ArgLenWithQuotes(args[i]) + 1;
187  }
188
189  // Now build the command line.
190  OwningArrayPtr<char> command(new char[len+1]);
191  char *p = command.get();
192
193  for (unsigned i = 0; args[i]; i++) {
194    const char *arg = args[i];
195    const char *start = arg;
196
197    bool needsQuoting = ArgNeedsQuotes(arg);
198    if (needsQuoting)
199      *p++ = '"';
200
201    while (*arg != '\0') {
202      if (*arg == '\"') {
203        // Escape all preceding escapes (if any), and then escape the quote.
204        p = EscapePrecedingEscapes(p, start, arg);
205        *p++ = '\\';
206      }
207
208      *p++ = *arg++;
209    }
210
211    if (needsQuoting) {
212      // Make sure our quote doesn't get escaped by a trailing backslash.
213      p = EscapePrecedingEscapes(p, start, arg);
214      *p++ = '"';
215    }
216    *p++ = ' ';
217  }
218
219  *p = 0;
220
221  // The pointer to the environment block for the new process.
222  std::vector<wchar_t> EnvBlock;
223
224  if (envp) {
225    // An environment block consists of a null-terminated block of
226    // null-terminated strings. Convert the array of environment variables to
227    // an environment block by concatenating them.
228    for (unsigned i = 0; envp[i]; ++i) {
229      SmallVector<wchar_t, MAX_PATH> EnvString;
230      if (error_code ec = windows::UTF8ToUTF16(envp[i], EnvString)) {
231        SetLastError(ec.value());
232        MakeErrMsg(ErrMsg, "Unable to convert environment variable to UTF-16");
233        return false;
234      }
235
236      EnvBlock.insert(EnvBlock.end(), EnvString.begin(), EnvString.end());
237      EnvBlock.push_back(0);
238    }
239    EnvBlock.push_back(0);
240  }
241
242  // Create a child process.
243  STARTUPINFOW si;
244  memset(&si, 0, sizeof(si));
245  si.cb = sizeof(si);
246  si.hStdInput = INVALID_HANDLE_VALUE;
247  si.hStdOutput = INVALID_HANDLE_VALUE;
248  si.hStdError = INVALID_HANDLE_VALUE;
249
250  if (redirects) {
251    si.dwFlags = STARTF_USESTDHANDLES;
252
253    si.hStdInput = RedirectIO(redirects[0], 0, ErrMsg);
254    if (si.hStdInput == INVALID_HANDLE_VALUE) {
255      MakeErrMsg(ErrMsg, "can't redirect stdin");
256      return false;
257    }
258    si.hStdOutput = RedirectIO(redirects[1], 1, ErrMsg);
259    if (si.hStdOutput == INVALID_HANDLE_VALUE) {
260      CloseHandle(si.hStdInput);
261      MakeErrMsg(ErrMsg, "can't redirect stdout");
262      return false;
263    }
264    if (redirects[1] && redirects[2] && *(redirects[1]) == *(redirects[2])) {
265      // If stdout and stderr should go to the same place, redirect stderr
266      // to the handle already open for stdout.
267      if (!DuplicateHandle(GetCurrentProcess(), si.hStdOutput,
268                           GetCurrentProcess(), &si.hStdError,
269                           0, TRUE, DUPLICATE_SAME_ACCESS)) {
270        CloseHandle(si.hStdInput);
271        CloseHandle(si.hStdOutput);
272        MakeErrMsg(ErrMsg, "can't dup stderr to stdout");
273        return false;
274      }
275    } else {
276      // Just redirect stderr
277      si.hStdError = RedirectIO(redirects[2], 2, ErrMsg);
278      if (si.hStdError == INVALID_HANDLE_VALUE) {
279        CloseHandle(si.hStdInput);
280        CloseHandle(si.hStdOutput);
281        MakeErrMsg(ErrMsg, "can't redirect stderr");
282        return false;
283      }
284    }
285  }
286
287  PROCESS_INFORMATION pi;
288  memset(&pi, 0, sizeof(pi));
289
290  fflush(stdout);
291  fflush(stderr);
292
293  SmallVector<wchar_t, MAX_PATH> ProgramUtf16;
294  if (error_code ec = windows::UTF8ToUTF16(Program, ProgramUtf16)) {
295    SetLastError(ec.value());
296    MakeErrMsg(ErrMsg,
297               std::string("Unable to convert application name to UTF-16"));
298    return false;
299  }
300
301  SmallVector<wchar_t, MAX_PATH> CommandUtf16;
302  if (error_code ec = windows::UTF8ToUTF16(command.get(), CommandUtf16)) {
303    SetLastError(ec.value());
304    MakeErrMsg(ErrMsg,
305               std::string("Unable to convert command-line to UTF-16"));
306    return false;
307  }
308
309  BOOL rc = CreateProcessW(ProgramUtf16.data(), CommandUtf16.data(), 0, 0,
310                           TRUE, CREATE_UNICODE_ENVIRONMENT,
311                           EnvBlock.empty() ? 0 : EnvBlock.data(), 0, &si,
312                           &pi);
313  DWORD err = GetLastError();
314
315  // Regardless of whether the process got created or not, we are done with
316  // the handles we created for it to inherit.
317  CloseHandle(si.hStdInput);
318  CloseHandle(si.hStdOutput);
319  CloseHandle(si.hStdError);
320
321  // Now return an error if the process didn't get created.
322  if (!rc) {
323    SetLastError(err);
324    MakeErrMsg(ErrMsg, std::string("Couldn't execute program '") +
325               Program.str() + "'");
326    return false;
327  }
328
329  PI.Pid = pi.dwProcessId;
330  PI.ProcessHandle = pi.hProcess;
331
332  // Make sure these get closed no matter what.
333  ScopedCommonHandle hThread(pi.hThread);
334
335  // Assign the process to a job if a memory limit is defined.
336  ScopedJobHandle hJob;
337  if (memoryLimit != 0) {
338    hJob = CreateJobObjectW(0, 0);
339    bool success = false;
340    if (hJob) {
341      JOBOBJECT_EXTENDED_LIMIT_INFORMATION jeli;
342      memset(&jeli, 0, sizeof(jeli));
343      jeli.BasicLimitInformation.LimitFlags = JOB_OBJECT_LIMIT_PROCESS_MEMORY;
344      jeli.ProcessMemoryLimit = uintptr_t(memoryLimit) * 1048576;
345      if (SetInformationJobObject(hJob, JobObjectExtendedLimitInformation,
346                                  &jeli, sizeof(jeli))) {
347        if (AssignProcessToJobObject(hJob, pi.hProcess))
348          success = true;
349      }
350    }
351    if (!success) {
352      SetLastError(GetLastError());
353      MakeErrMsg(ErrMsg, std::string("Unable to set memory limit"));
354      TerminateProcess(pi.hProcess, 1);
355      WaitForSingleObject(pi.hProcess, INFINITE);
356      return false;
357    }
358  }
359
360  return true;
361}
362
363namespace llvm {
364ProcessInfo sys::Wait(const ProcessInfo &PI, unsigned SecondsToWait,
365                      bool WaitUntilChildTerminates, std::string *ErrMsg) {
366  assert(PI.Pid && "invalid pid to wait on, process not started?");
367  assert(PI.ProcessHandle &&
368         "invalid process handle to wait on, process not started?");
369  DWORD milliSecondsToWait = 0;
370  if (WaitUntilChildTerminates)
371    milliSecondsToWait = INFINITE;
372  else if (SecondsToWait > 0)
373    milliSecondsToWait = SecondsToWait * 1000;
374
375  ProcessInfo WaitResult = PI;
376  DWORD WaitStatus = WaitForSingleObject(PI.ProcessHandle, milliSecondsToWait);
377  if (WaitStatus == WAIT_TIMEOUT) {
378    if (SecondsToWait) {
379      if (!TerminateProcess(PI.ProcessHandle, 1)) {
380        if (ErrMsg)
381          MakeErrMsg(ErrMsg, "Failed to terminate timed-out program.");
382
383        // -2 indicates a crash or timeout as opposed to failure to execute.
384        WaitResult.ReturnCode = -2;
385        CloseHandle(PI.ProcessHandle);
386        return WaitResult;
387      }
388      WaitForSingleObject(PI.ProcessHandle, INFINITE);
389      CloseHandle(PI.ProcessHandle);
390    } else {
391      // Non-blocking wait.
392      return ProcessInfo();
393    }
394  }
395
396  // Get its exit status.
397  DWORD status;
398  BOOL rc = GetExitCodeProcess(PI.ProcessHandle, &status);
399  DWORD err = GetLastError();
400  CloseHandle(PI.ProcessHandle);
401
402  if (!rc) {
403    SetLastError(err);
404    if (ErrMsg)
405      MakeErrMsg(ErrMsg, "Failed getting status for program.");
406
407    // -2 indicates a crash or timeout as opposed to failure to execute.
408    WaitResult.ReturnCode = -2;
409    return WaitResult;
410  }
411
412  if (!status)
413    return WaitResult;
414
415  // Pass 10(Warning) and 11(Error) to the callee as negative value.
416  if ((status & 0xBFFF0000U) == 0x80000000U)
417    WaitResult.ReturnCode = static_cast<int>(status);
418  else if (status & 0xFF)
419    WaitResult.ReturnCode = status & 0x7FFFFFFF;
420  else
421    WaitResult.ReturnCode = 1;
422
423  return WaitResult;
424}
425
426error_code sys::ChangeStdinToBinary(){
427  int result = _setmode( _fileno(stdin), _O_BINARY );
428  if (result == -1)
429    return error_code(errno, generic_category());
430  return make_error_code(errc::success);
431}
432
433error_code sys::ChangeStdoutToBinary(){
434  int result = _setmode( _fileno(stdout), _O_BINARY );
435  if (result == -1)
436    return error_code(errno, generic_category());
437  return make_error_code(errc::success);
438}
439
440error_code sys::ChangeStderrToBinary(){
441  int result = _setmode( _fileno(stderr), _O_BINARY );
442  if (result == -1)
443    return error_code(errno, generic_category());
444  return make_error_code(errc::success);
445}
446
447bool llvm::sys::argumentsFitWithinSystemLimits(ArrayRef<const char*> Args) {
448  // The documented max length of the command line passed to CreateProcess.
449  static const size_t MaxCommandStringLength = 32768;
450  size_t ArgLength = 0;
451  for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end();
452       I != E; ++I) {
453    // Account for the trailing space for every arg but the last one and the
454    // trailing NULL of the last argument.
455    ArgLength += ArgLenWithQuotes(*I) + 1;
456    if (ArgLength > MaxCommandStringLength) {
457      return false;
458    }
459  }
460  return true;
461}
462}
463