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raw_ostream.cpp
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1 //===--- raw_ostream.cpp - Implement the raw_ostream classes --------------===//
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 implements support for bulk buffered stream output.
11 //
12 //===----------------------------------------------------------------------===//
13 
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/StringExtras.h"
18 #include "llvm/Config/config.h"
19 #include "llvm/Support/Compiler.h"
22 #include "llvm/Support/Format.h"
23 #include "llvm/Support/Process.h"
24 #include "llvm/Support/Program.h"
26 #include <cctype>
27 #include <cerrno>
28 #include <sys/stat.h>
29 
30 // <fcntl.h> may provide O_BINARY.
31 #if defined(HAVE_FCNTL_H)
32 # include <fcntl.h>
33 #endif
34 
35 #if defined(HAVE_UNISTD_H)
36 # include <unistd.h>
37 #endif
38 #if defined(HAVE_SYS_UIO_H) && defined(HAVE_WRITEV)
39 # include <sys/uio.h>
40 #endif
41 
42 #if defined(__CYGWIN__)
43 #include <io.h>
44 #endif
45 
46 #if defined(_MSC_VER)
47 #include <io.h>
48 #ifndef STDIN_FILENO
49 # define STDIN_FILENO 0
50 #endif
51 #ifndef STDOUT_FILENO
52 # define STDOUT_FILENO 1
53 #endif
54 #ifndef STDERR_FILENO
55 # define STDERR_FILENO 2
56 #endif
57 #endif
58 
59 using namespace llvm;
60 
62  // raw_ostream's subclasses should take care to flush the buffer
63  // in their destructors.
64  assert(OutBufCur == OutBufStart &&
65  "raw_ostream destructor called with non-empty buffer!");
66 
67  if (BufferMode == InternalBuffer)
68  delete [] OutBufStart;
69 }
70 
71 // An out of line virtual method to provide a home for the class vtable.
72 void raw_ostream::handle() {}
73 
75  // BUFSIZ is intended to be a reasonable default.
76  return BUFSIZ;
77 }
78 
80  // Ask the subclass to determine an appropriate buffer size.
81  if (size_t Size = preferred_buffer_size())
82  SetBufferSize(Size);
83  else
84  // It may return 0, meaning this stream should be unbuffered.
85  SetUnbuffered();
86 }
87 
88 void raw_ostream::SetBufferAndMode(char *BufferStart, size_t Size,
89  BufferKind Mode) {
90  assert(((Mode == Unbuffered && BufferStart == 0 && Size == 0) ||
91  (Mode != Unbuffered && BufferStart && Size)) &&
92  "stream must be unbuffered or have at least one byte");
93  // Make sure the current buffer is free of content (we can't flush here; the
94  // child buffer management logic will be in write_impl).
95  assert(GetNumBytesInBuffer() == 0 && "Current buffer is non-empty!");
96 
97  if (BufferMode == InternalBuffer)
98  delete [] OutBufStart;
99  OutBufStart = BufferStart;
100  OutBufEnd = OutBufStart+Size;
101  OutBufCur = OutBufStart;
102  BufferMode = Mode;
103 
104  assert(OutBufStart <= OutBufEnd && "Invalid size!");
105 }
106 
108  // Zero is a special case.
109  if (N == 0)
110  return *this << '0';
111 
112  char NumberBuffer[20];
113  char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
114  char *CurPtr = EndPtr;
115 
116  while (N) {
117  *--CurPtr = '0' + char(N % 10);
118  N /= 10;
119  }
120  return write(CurPtr, EndPtr-CurPtr);
121 }
122 
124  if (N < 0) {
125  *this << '-';
126  // Avoid undefined behavior on LONG_MIN with a cast.
127  N = -(unsigned long)N;
128  }
129 
130  return this->operator<<(static_cast<unsigned long>(N));
131 }
132 
133 raw_ostream &raw_ostream::operator<<(unsigned long long N) {
134  // Output using 32-bit div/mod when possible.
135  if (N == static_cast<unsigned long>(N))
136  return this->operator<<(static_cast<unsigned long>(N));
137 
138  char NumberBuffer[20];
139  char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
140  char *CurPtr = EndPtr;
141 
142  while (N) {
143  *--CurPtr = '0' + char(N % 10);
144  N /= 10;
145  }
146  return write(CurPtr, EndPtr-CurPtr);
147 }
148 
150  if (N < 0) {
151  *this << '-';
152  // Avoid undefined behavior on INT64_MIN with a cast.
153  N = -(unsigned long long)N;
154  }
155 
156  return this->operator<<(static_cast<unsigned long long>(N));
157 }
158 
159 raw_ostream &raw_ostream::write_hex(unsigned long long N) {
160  // Zero is a special case.
161  if (N == 0)
162  return *this << '0';
163 
164  char NumberBuffer[20];
165  char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
166  char *CurPtr = EndPtr;
167 
168  while (N) {
169  uintptr_t x = N % 16;
170  *--CurPtr = (x < 10 ? '0' + x : 'a' + x - 10);
171  N /= 16;
172  }
173 
174  return write(CurPtr, EndPtr-CurPtr);
175 }
176 
178  bool UseHexEscapes) {
179  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
180  unsigned char c = Str[i];
181 
182  switch (c) {
183  case '\\':
184  *this << '\\' << '\\';
185  break;
186  case '\t':
187  *this << '\\' << 't';
188  break;
189  case '\n':
190  *this << '\\' << 'n';
191  break;
192  case '"':
193  *this << '\\' << '"';
194  break;
195  default:
196  if (std::isprint(c)) {
197  *this << c;
198  break;
199  }
200 
201  // Write out the escaped representation.
202  if (UseHexEscapes) {
203  *this << '\\' << 'x';
204  *this << hexdigit((c >> 4 & 0xF));
205  *this << hexdigit((c >> 0) & 0xF);
206  } else {
207  // Always use a full 3-character octal escape.
208  *this << '\\';
209  *this << char('0' + ((c >> 6) & 7));
210  *this << char('0' + ((c >> 3) & 7));
211  *this << char('0' + ((c >> 0) & 7));
212  }
213  }
214  }
215 
216  return *this;
217 }
218 
220  *this << '0' << 'x';
221 
222  return write_hex((uintptr_t) P);
223 }
224 
226 #ifdef _WIN32
227  // On MSVCRT and compatible, output of %e is incompatible to Posix
228  // by default. Number of exponent digits should be at least 2. "%+03d"
229  // FIXME: Implement our formatter to here or Support/Format.h!
230  int fpcl = _fpclass(N);
231 
232  // negative zero
233  if (fpcl == _FPCLASS_NZ)
234  return *this << "-0.000000e+00";
235 
236  char buf[16];
237  unsigned len;
238  len = snprintf(buf, sizeof(buf), "%e", N);
239  if (len <= sizeof(buf) - 2) {
240  if (len >= 5 && buf[len - 5] == 'e' && buf[len - 3] == '0') {
241  int cs = buf[len - 4];
242  if (cs == '+' || cs == '-') {
243  int c1 = buf[len - 2];
244  int c0 = buf[len - 1];
245  if (isdigit(static_cast<unsigned char>(c1)) &&
246  isdigit(static_cast<unsigned char>(c0))) {
247  // Trim leading '0': "...e+012" -> "...e+12\0"
248  buf[len - 3] = c1;
249  buf[len - 2] = c0;
250  buf[--len] = 0;
251  }
252  }
253  }
254  return this->operator<<(buf);
255  }
256 #endif
257  return this->operator<<(format("%e", N));
258 }
259 
260 
261 
262 void raw_ostream::flush_nonempty() {
263  assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty.");
264  size_t Length = OutBufCur - OutBufStart;
265  OutBufCur = OutBufStart;
266  write_impl(OutBufStart, Length);
267 }
268 
270  // Group exceptional cases into a single branch.
271  if (LLVM_UNLIKELY(OutBufCur >= OutBufEnd)) {
272  if (LLVM_UNLIKELY(!OutBufStart)) {
273  if (BufferMode == Unbuffered) {
274  write_impl(reinterpret_cast<char*>(&C), 1);
275  return *this;
276  }
277  // Set up a buffer and start over.
278  SetBuffered();
279  return write(C);
280  }
281 
282  flush_nonempty();
283  }
284 
285  *OutBufCur++ = C;
286  return *this;
287 }
288 
289 raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) {
290  // Group exceptional cases into a single branch.
291  if (LLVM_UNLIKELY(size_t(OutBufEnd - OutBufCur) < Size)) {
292  if (LLVM_UNLIKELY(!OutBufStart)) {
293  if (BufferMode == Unbuffered) {
294  write_impl(Ptr, Size);
295  return *this;
296  }
297  // Set up a buffer and start over.
298  SetBuffered();
299  return write(Ptr, Size);
300  }
301 
302  size_t NumBytes = OutBufEnd - OutBufCur;
303 
304  // If the buffer is empty at this point we have a string that is larger
305  // than the buffer. Directly write the chunk that is a multiple of the
306  // preferred buffer size and put the remainder in the buffer.
307  if (LLVM_UNLIKELY(OutBufCur == OutBufStart)) {
308  size_t BytesToWrite = Size - (Size % NumBytes);
309  write_impl(Ptr, BytesToWrite);
310  size_t BytesRemaining = Size - BytesToWrite;
311  if (BytesRemaining > size_t(OutBufEnd - OutBufCur)) {
312  // Too much left over to copy into our buffer.
313  return write(Ptr + BytesToWrite, BytesRemaining);
314  }
315  copy_to_buffer(Ptr + BytesToWrite, BytesRemaining);
316  return *this;
317  }
318 
319  // We don't have enough space in the buffer to fit the string in. Insert as
320  // much as possible, flush and start over with the remainder.
321  copy_to_buffer(Ptr, NumBytes);
322  flush_nonempty();
323  return write(Ptr + NumBytes, Size - NumBytes);
324  }
325 
326  copy_to_buffer(Ptr, Size);
327 
328  return *this;
329 }
330 
331 void raw_ostream::copy_to_buffer(const char *Ptr, size_t Size) {
332  assert(Size <= size_t(OutBufEnd - OutBufCur) && "Buffer overrun!");
333 
334  // Handle short strings specially, memcpy isn't very good at very short
335  // strings.
336  switch (Size) {
337  case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH
338  case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH
339  case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH
340  case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH
341  case 0: break;
342  default:
343  memcpy(OutBufCur, Ptr, Size);
344  break;
345  }
346 
347  OutBufCur += Size;
348 }
349 
350 // Formatted output.
352  // If we have more than a few bytes left in our output buffer, try
353  // formatting directly onto its end.
354  size_t NextBufferSize = 127;
355  size_t BufferBytesLeft = OutBufEnd - OutBufCur;
356  if (BufferBytesLeft > 3) {
357  size_t BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft);
358 
359  // Common case is that we have plenty of space.
360  if (BytesUsed <= BufferBytesLeft) {
361  OutBufCur += BytesUsed;
362  return *this;
363  }
364 
365  // Otherwise, we overflowed and the return value tells us the size to try
366  // again with.
367  NextBufferSize = BytesUsed;
368  }
369 
370  // If we got here, we didn't have enough space in the output buffer for the
371  // string. Try printing into a SmallVector that is resized to have enough
372  // space. Iterate until we win.
374 
375  while (1) {
376  V.resize(NextBufferSize);
377 
378  // Try formatting into the SmallVector.
379  size_t BytesUsed = Fmt.print(V.data(), NextBufferSize);
380 
381  // If BytesUsed fit into the vector, we win.
382  if (BytesUsed <= NextBufferSize)
383  return write(V.data(), BytesUsed);
384 
385  // Otherwise, try again with a new size.
386  assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?");
387  NextBufferSize = BytesUsed;
388  }
389 }
390 
391 /// indent - Insert 'NumSpaces' spaces.
392 raw_ostream &raw_ostream::indent(unsigned NumSpaces) {
393  static const char Spaces[] = " "
394  " "
395  " ";
396 
397  // Usually the indentation is small, handle it with a fastpath.
398  if (NumSpaces < array_lengthof(Spaces))
399  return write(Spaces, NumSpaces);
400 
401  while (NumSpaces) {
402  unsigned NumToWrite = std::min(NumSpaces,
403  (unsigned)array_lengthof(Spaces)-1);
404  write(Spaces, NumToWrite);
405  NumSpaces -= NumToWrite;
406  }
407  return *this;
408 }
409 
410 
411 //===----------------------------------------------------------------------===//
412 // Formatted Output
413 //===----------------------------------------------------------------------===//
414 
415 // Out of line virtual method.
417 }
418 
419 //===----------------------------------------------------------------------===//
420 // raw_fd_ostream
421 //===----------------------------------------------------------------------===//
422 
423 /// raw_fd_ostream - Open the specified file for writing. If an error
424 /// occurs, information about the error is put into ErrorInfo, and the
425 /// stream should be immediately destroyed; the string will be empty
426 /// if no error occurred.
427 raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
429  : Error(false), UseAtomicWrites(false), pos(0) {
430  assert(Filename != 0 && "Filename is null");
431  ErrorInfo.clear();
432 
433  // Handle "-" as stdout. Note that when we do this, we consider ourself
434  // the owner of stdout. This means that we can do things like close the
435  // file descriptor when we're done and set the "binary" flag globally.
436  if (Filename[0] == '-' && Filename[1] == 0) {
437  FD = STDOUT_FILENO;
438  // If user requested binary then put stdout into binary mode if
439  // possible.
440  if (Flags & sys::fs::F_Binary)
442  // Close stdout when we're done, to detect any output errors.
443  ShouldClose = true;
444  return;
445  }
446 
447  error_code EC = sys::fs::openFileForWrite(Filename, FD, Flags);
448 
449  if (EC) {
450  ErrorInfo = "Error opening output file '" + std::string(Filename) + "': " +
451  EC.message();
452  ShouldClose = false;
453  return;
454  }
455 
456  // Ok, we successfully opened the file, so it'll need to be closed.
457  ShouldClose = true;
458 }
459 
460 /// raw_fd_ostream ctor - FD is the file descriptor that this writes to. If
461 /// ShouldClose is true, this closes the file when the stream is destroyed.
462 raw_fd_ostream::raw_fd_ostream(int fd, bool shouldClose, bool unbuffered)
463  : raw_ostream(unbuffered), FD(fd),
464  ShouldClose(shouldClose), Error(false), UseAtomicWrites(false) {
465 #ifdef O_BINARY
466  // Setting STDOUT and STDERR to binary mode is necessary in Win32
467  // to avoid undesirable linefeed conversion.
468  if (fd == STDOUT_FILENO || fd == STDERR_FILENO)
469  setmode(fd, O_BINARY);
470 #endif
471 
472  // Get the starting position.
473  off_t loc = ::lseek(FD, 0, SEEK_CUR);
474  if (loc == (off_t)-1)
475  pos = 0;
476  else
477  pos = static_cast<uint64_t>(loc);
478 }
479 
481  if (FD >= 0) {
482  flush();
483  if (ShouldClose)
484  while (::close(FD) != 0)
485  if (errno != EINTR) {
486  error_detected();
487  break;
488  }
489  }
490 
491 #ifdef __MINGW32__
492  // On mingw, global dtors should not call exit().
493  // report_fatal_error() invokes exit(). We know report_fatal_error()
494  // might not write messages to stderr when any errors were detected
495  // on FD == 2.
496  if (FD == 2) return;
497 #endif
498 
499  // If there are any pending errors, report them now. Clients wishing
500  // to avoid report_fatal_error calls should check for errors with
501  // has_error() and clear the error flag with clear_error() before
502  // destructing raw_ostream objects which may have errors.
503  if (has_error())
504  report_fatal_error("IO failure on output stream.", /*GenCrashDiag=*/false);
505 }
506 
507 
508 void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
509  assert(FD >= 0 && "File already closed.");
510  pos += Size;
511 
512  do {
513  ssize_t ret;
514 
515  // Check whether we should attempt to use atomic writes.
516  if (LLVM_LIKELY(!UseAtomicWrites)) {
517  ret = ::write(FD, Ptr, Size);
518  } else {
519  // Use ::writev() where available.
520 #if defined(HAVE_WRITEV)
521  const void *Addr = static_cast<const void *>(Ptr);
522  struct iovec IOV = {const_cast<void *>(Addr), Size };
523  ret = ::writev(FD, &IOV, 1);
524 #else
525  ret = ::write(FD, Ptr, Size);
526 #endif
527  }
528 
529  if (ret < 0) {
530  // If it's a recoverable error, swallow it and retry the write.
531  //
532  // Ideally we wouldn't ever see EAGAIN or EWOULDBLOCK here, since
533  // raw_ostream isn't designed to do non-blocking I/O. However, some
534  // programs, such as old versions of bjam, have mistakenly used
535  // O_NONBLOCK. For compatibility, emulate blocking semantics by
536  // spinning until the write succeeds. If you don't want spinning,
537  // don't use O_NONBLOCK file descriptors with raw_ostream.
538  if (errno == EINTR || errno == EAGAIN
539 #ifdef EWOULDBLOCK
540  || errno == EWOULDBLOCK
541 #endif
542  )
543  continue;
544 
545  // Otherwise it's a non-recoverable error. Note it and quit.
546  error_detected();
547  break;
548  }
549 
550  // The write may have written some or all of the data. Update the
551  // size and buffer pointer to reflect the remainder that needs
552  // to be written. If there are no bytes left, we're done.
553  Ptr += ret;
554  Size -= ret;
555  } while (Size > 0);
556 }
557 
559  assert(ShouldClose);
560  ShouldClose = false;
561  flush();
562  while (::close(FD) != 0)
563  if (errno != EINTR) {
564  error_detected();
565  break;
566  }
567  FD = -1;
568 }
569 
570 uint64_t raw_fd_ostream::seek(uint64_t off) {
571  flush();
572  pos = ::lseek(FD, off, SEEK_SET);
573  if (pos != off)
574  error_detected();
575  return pos;
576 }
577 
578 size_t raw_fd_ostream::preferred_buffer_size() const {
579 #if !defined(_MSC_VER) && !defined(__MINGW32__)
580  // Windows has no st_blksize.
581  assert(FD >= 0 && "File not yet open!");
582  struct stat statbuf;
583  if (fstat(FD, &statbuf) != 0)
584  return 0;
585 
586  // If this is a terminal, don't use buffering. Line buffering
587  // would be a more traditional thing to do, but it's not worth
588  // the complexity.
589  if (S_ISCHR(statbuf.st_mode) && isatty(FD))
590  return 0;
591  // Return the preferred block size.
592  return statbuf.st_blksize;
593 #else
595 #endif
596 }
597 
599  bool bg) {
601  flush();
602  const char *colorcode =
603  (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg)
604  : sys::Process::OutputColor(colors, bold, bg);
605  if (colorcode) {
606  size_t len = strlen(colorcode);
607  write(colorcode, len);
608  // don't account colors towards output characters
609  pos -= len;
610  }
611  return *this;
612 }
613 
616  flush();
617  const char *colorcode = sys::Process::ResetColor();
618  if (colorcode) {
619  size_t len = strlen(colorcode);
620  write(colorcode, len);
621  // don't account colors towards output characters
622  pos -= len;
623  }
624  return *this;
625 }
626 
629  flush();
630  const char *colorcode = sys::Process::OutputReverse();
631  if (colorcode) {
632  size_t len = strlen(colorcode);
633  write(colorcode, len);
634  // don't account colors towards output characters
635  pos -= len;
636  }
637  return *this;
638 }
639 
642 }
643 
646 }
647 
648 //===----------------------------------------------------------------------===//
649 // outs(), errs(), nulls()
650 //===----------------------------------------------------------------------===//
651 
652 /// outs() - This returns a reference to a raw_ostream for standard output.
653 /// Use it like: outs() << "foo" << "bar";
655  // Set buffer settings to model stdout behavior.
656  // Delete the file descriptor when the program exists, forcing error
657  // detection. If you don't want this behavior, don't use outs().
658  static raw_fd_ostream S(STDOUT_FILENO, true);
659  return S;
660 }
661 
662 /// errs() - This returns a reference to a raw_ostream for standard error.
663 /// Use it like: errs() << "foo" << "bar";
665  // Set standard error to be unbuffered by default.
666  static raw_fd_ostream S(STDERR_FILENO, false, true);
667  return S;
668 }
669 
670 /// nulls() - This returns a reference to a raw_ostream which discards output.
672  static raw_null_ostream S;
673  return S;
674 }
675 
676 
677 //===----------------------------------------------------------------------===//
678 // raw_string_ostream
679 //===----------------------------------------------------------------------===//
680 
682  flush();
683 }
684 
685 void raw_string_ostream::write_impl(const char *Ptr, size_t Size) {
686  OS.append(Ptr, Size);
687 }
688 
689 //===----------------------------------------------------------------------===//
690 // raw_svector_ostream
691 //===----------------------------------------------------------------------===//
692 
693 // The raw_svector_ostream implementation uses the SmallVector itself as the
694 // buffer for the raw_ostream. We guarantee that the raw_ostream buffer is
695 // always pointing past the end of the vector, but within the vector
696 // capacity. This allows raw_ostream to write directly into the correct place,
697 // and we only need to set the vector size when the data is flushed.
698 
700  // Set up the initial external buffer. We make sure that the buffer has at
701  // least 128 bytes free; raw_ostream itself only requires 64, but we want to
702  // make sure that we don't grow the buffer unnecessarily on destruction (when
703  // the data is flushed). See the FIXME below.
704  OS.reserve(OS.size() + 128);
705  SetBuffer(OS.end(), OS.capacity() - OS.size());
706 }
707 
709  // FIXME: Prevent resizing during this flush().
710  flush();
711 }
712 
713 /// resync - This is called when the SmallVector we're appending to is changed
714 /// outside of the raw_svector_ostream's control. It is only safe to do this
715 /// if the raw_svector_ostream has previously been flushed.
717  assert(GetNumBytesInBuffer() == 0 && "Didn't flush before mutating vector");
718 
719  if (OS.capacity() - OS.size() < 64)
720  OS.reserve(OS.capacity() * 2);
721  SetBuffer(OS.end(), OS.capacity() - OS.size());
722 }
723 
724 void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) {
725  // If we're writing bytes from the end of the buffer into the smallvector, we
726  // don't need to copy the bytes, just commit the bytes because they are
727  // already in the right place.
728  if (Ptr == OS.end()) {
729  assert(OS.size() + Size <= OS.capacity() && "Invalid write_impl() call!");
730  OS.set_size(OS.size() + Size);
731  } else {
732  assert(GetNumBytesInBuffer() == 0 &&
733  "Should be writing from buffer if some bytes in it");
734  // Otherwise, do copy the bytes.
735  OS.append(Ptr, Ptr+Size);
736  }
737 
738  // Grow the vector if necessary.
739  if (OS.capacity() - OS.size() < 64)
740  OS.reserve(OS.capacity() * 2);
741 
742  // Update the buffer position.
743  SetBuffer(OS.end(), OS.capacity() - OS.size());
744 }
745 
746 uint64_t raw_svector_ostream::current_pos() const {
747  return OS.size();
748 }
749 
751  flush();
752  return StringRef(OS.begin(), OS.size());
753 }
754 
755 //===----------------------------------------------------------------------===//
756 // raw_null_ostream
757 //===----------------------------------------------------------------------===//
758 
760 #ifndef NDEBUG
761  // ~raw_ostream asserts that the buffer is empty. This isn't necessary
762  // with raw_null_ostream, but it's better to have raw_null_ostream follow
763  // the rules than to change the rules just for raw_null_ostream.
764  flush();
765 #endif
766 }
767 
768 void raw_null_ostream::write_impl(const char *Ptr, size_t Size) {
769 }
770 
771 uint64_t raw_null_ostream::current_pos() const {
772  return 0;
773 }
void set_size(unsigned N)
Definition: SmallVector.h:702
raw_ostream & errs()
void reserve(unsigned N)
Definition: SmallVector.h:425
virtual raw_ostream & resetColor() LLVM_OVERRIDE
size_t size() const
size - Get the string size.
Definition: StringRef.h:113
int fstat(int fildes, struct stat *buf);
error_code openFileForWrite(const Twine &Name, int &ResultFD, OpenFlags Flags, unsigned Mode=0666)
static const char * ResetColor()
Resets the terminals colors, or returns an escape sequence to do so.
#define LLVM_UNLIKELY(EXPR)
Definition: Compiler.h:231
#define LLVM_LIKELY(EXPR)
Definition: Compiler.h:230
static const char * OutputColor(char c, bool bold, bool bg)
raw_null_ostream - A raw_ostream that discards all output.
Definition: raw_ostream.h:478
virtual ~raw_ostream()
Definition: raw_ostream.cpp:61
uint64_t seek(uint64_t off)
raw_ostream & indent(unsigned NumSpaces)
indent - Insert 'NumSpaces' spaces.
static bool FileDescriptorHasColors(int fd)
int isdigit(int c);
static bool FileDescriptorIsDisplayed(int fd)
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const char *reason, bool gen_crash_diag=true)
static bool ColorNeedsFlush()
bool has_error() const
Definition: raw_ostream.h:390
static const char * OutputReverse()
void SetBuffer(char *BufferStart, size_t Size)
Definition: raw_ostream.h:275
raw_svector_ostream(SmallVectorImpl< char > &O)
#define false
Definition: ConvertUTF.c:64
format_object1< T > format(const char *Fmt, const T &Val)
Definition: Format.h:180
size_t array_lengthof(T(&)[N])
Find the length of an array.
Definition: STLExtras.h:250
raw_ostream & write_hex(unsigned long long N)
write_hex - Output N in hexadecimal, without any prefix or padding.
raw_ostream & operator<<(char C)
Definition: raw_ostream.h:134
unsigned print(char *Buffer, unsigned BufferSize) const
Definition: Format.h:56
raw_ostream & outs()
#define P(N)
virtual raw_ostream & changeColor(enum Colors colors, bool bold=false, bool bg=false) LLVM_OVERRIDE
raw_fd_ostream(const char *Filename, std::string &ErrorInfo, sys::fs::OpenFlags Flags=sys::fs::F_None)
int snprintf(char *s, size_t n, const char *format, ...);
void append(in_iter in_start, in_iter in_end)
Definition: SmallVector.h:445
void SetBufferSize(size_t Size)
Definition: raw_ostream.h:97
int stat(const char *path, struct stat *buf);
raw_ostream & write(unsigned char C)
raw_ostream & write_escaped(StringRef Str, bool UseHexEscapes=false)
virtual bool has_colors() const LLVM_OVERRIDE
This function determines if this stream is displayed and supports colors.
virtual size_t preferred_buffer_size() const
Definition: raw_ostream.cpp:74
size_t strlen(const char *s);
std::string message() const
pointer data()
data - Return a pointer to the vector's buffer, even if empty().
Definition: SmallVector.h:135
virtual raw_ostream & reverseColor() LLVM_OVERRIDE
Reverses the forground and background colors.
#define N
void resize(unsigned N)
Definition: SmallVector.h:401
static const char * OutputBold(bool bg)
Same as OutputColor, but only enables the bold attribute.
raw_ostream & nulls()
nulls() - This returns a reference to a raw_ostream which discards output.
virtual bool is_displayed() const LLVM_OVERRIDE
error_code ChangeStdoutToBinary()
size_t GetNumBytesInBuffer() const
Definition: raw_ostream.h:121