1 //===--- raw_ostream.cpp - Implement the raw_ostream classes --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This implements support for bulk buffered stream output.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Support/raw_ostream.h"
15 #include "llvm/Support/Format.h"
16 #include "llvm/System/Program.h"
17 #include "llvm/System/Process.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/Config/config.h"
20 #include "llvm/Support/Compiler.h"
21 #include "llvm/Support/ErrorHandling.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/ADT/StringExtras.h"
25 #include <sys/types.h>
27 #if defined(HAVE_UNISTD_H)
30 #if defined(HAVE_FCNTL_H)
38 # define STDIN_FILENO 0
41 # define STDOUT_FILENO 1
44 # define STDERR_FILENO 2
50 raw_ostream::~raw_ostream() {
51 // raw_ostream's subclasses should take care to flush the buffer
52 // in their destructors.
53 assert(OutBufCur == OutBufStart &&
54 "raw_ostream destructor called with non-empty buffer!");
56 if (BufferMode == InternalBuffer)
57 delete [] OutBufStart;
59 // If there are any pending errors, report them now. Clients wishing
60 // to avoid llvm_report_error calls should check for errors with
61 // has_error() and clear the error flag with clear_error() before
62 // destructing raw_ostream objects which may have errors.
64 llvm_report_error("IO failure on output stream.");
67 // An out of line virtual method to provide a home for the class vtable.
68 void raw_ostream::handle() {}
70 size_t raw_ostream::preferred_buffer_size() {
71 // BUFSIZ is intended to be a reasonable default.
75 void raw_ostream::SetBuffered() {
76 // Ask the subclass to determine an appropriate buffer size.
77 if (size_t Size = preferred_buffer_size())
80 // It may return 0, meaning this stream should be unbuffered.
84 void raw_ostream::SetBufferAndMode(char *BufferStart, size_t Size,
86 assert(((Mode == Unbuffered && BufferStart == 0 && Size == 0) ||
87 (Mode != Unbuffered && BufferStart && Size)) &&
88 "stream must be unbuffered or have at least one byte");
89 // Make sure the current buffer is free of content (we can't flush here; the
90 // child buffer management logic will be in write_impl).
91 assert(GetNumBytesInBuffer() == 0 && "Current buffer is non-empty!");
93 if (BufferMode == InternalBuffer)
94 delete [] OutBufStart;
95 OutBufStart = BufferStart;
96 OutBufEnd = OutBufStart+Size;
97 OutBufCur = OutBufStart;
100 assert(OutBufStart <= OutBufEnd && "Invalid size!");
103 raw_ostream &raw_ostream::operator<<(unsigned long N) {
104 // Zero is a special case.
108 char NumberBuffer[20];
109 char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
110 char *CurPtr = EndPtr;
113 *--CurPtr = '0' + char(N % 10);
116 return write(CurPtr, EndPtr-CurPtr);
119 raw_ostream &raw_ostream::operator<<(long N) {
125 return this->operator<<(static_cast<unsigned long>(N));
128 raw_ostream &raw_ostream::operator<<(unsigned long long N) {
129 // Output using 32-bit div/mod when possible.
130 if (N == static_cast<unsigned long>(N))
131 return this->operator<<(static_cast<unsigned long>(N));
133 char NumberBuffer[20];
134 char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
135 char *CurPtr = EndPtr;
138 *--CurPtr = '0' + char(N % 10);
141 return write(CurPtr, EndPtr-CurPtr);
144 raw_ostream &raw_ostream::operator<<(long long N) {
150 return this->operator<<(static_cast<unsigned long long>(N));
153 raw_ostream &raw_ostream::write_hex(unsigned long long N) {
154 // Zero is a special case.
158 char NumberBuffer[20];
159 char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
160 char *CurPtr = EndPtr;
163 uintptr_t x = N % 16;
164 *--CurPtr = (x < 10 ? '0' + x : 'a' + x - 10);
168 return write(CurPtr, EndPtr-CurPtr);
171 raw_ostream &raw_ostream::write_escaped(StringRef Str) {
172 for (unsigned i = 0, e = Str.size(); i != e; ++i) {
173 unsigned char c = Str[i];
177 *this << '\\' << '\\';
180 *this << '\\' << 't';
183 *this << '\\' << 'n';
186 *this << '\\' << '"';
189 if (std::isprint(c)) {
194 // Always expand to a 3-character octal escape.
196 *this << char('0' + ((c >> 6) & 7));
197 *this << char('0' + ((c >> 3) & 7));
198 *this << char('0' + ((c >> 0) & 7));
205 raw_ostream &raw_ostream::operator<<(const void *P) {
208 return write_hex((uintptr_t) P);
211 raw_ostream &raw_ostream::operator<<(double N) {
212 return this->operator<<(ftostr(N));
217 void raw_ostream::flush_nonempty() {
218 assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty.");
219 size_t Length = OutBufCur - OutBufStart;
220 OutBufCur = OutBufStart;
221 write_impl(OutBufStart, Length);
224 raw_ostream &raw_ostream::write(unsigned char C) {
225 // Group exceptional cases into a single branch.
226 if (BUILTIN_EXPECT(OutBufCur >= OutBufEnd, false)) {
227 if (BUILTIN_EXPECT(!OutBufStart, false)) {
228 if (BufferMode == Unbuffered) {
229 write_impl(reinterpret_cast<char*>(&C), 1);
232 // Set up a buffer and start over.
244 raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) {
245 // Group exceptional cases into a single branch.
246 if (BUILTIN_EXPECT(OutBufCur+Size > OutBufEnd, false)) {
247 if (BUILTIN_EXPECT(!OutBufStart, false)) {
248 if (BufferMode == Unbuffered) {
249 write_impl(Ptr, Size);
252 // Set up a buffer and start over.
254 return write(Ptr, Size);
257 // Write out the data in buffer-sized blocks until the remainder
258 // fits within the buffer.
260 size_t NumBytes = OutBufEnd - OutBufCur;
261 copy_to_buffer(Ptr, NumBytes);
265 } while (OutBufCur+Size > OutBufEnd);
268 copy_to_buffer(Ptr, Size);
273 void raw_ostream::copy_to_buffer(const char *Ptr, size_t Size) {
274 assert(Size <= size_t(OutBufEnd - OutBufCur) && "Buffer overrun!");
276 // Handle short strings specially, memcpy isn't very good at very short
279 case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH
280 case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH
281 case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH
282 case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH
285 memcpy(OutBufCur, Ptr, Size);
293 raw_ostream &raw_ostream::operator<<(const format_object_base &Fmt) {
294 // If we have more than a few bytes left in our output buffer, try
295 // formatting directly onto its end.
296 size_t NextBufferSize = 127;
297 size_t BufferBytesLeft = OutBufEnd - OutBufCur;
298 if (BufferBytesLeft > 3) {
299 size_t BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft);
301 // Common case is that we have plenty of space.
302 if (BytesUsed <= BufferBytesLeft) {
303 OutBufCur += BytesUsed;
307 // Otherwise, we overflowed and the return value tells us the size to try
309 NextBufferSize = BytesUsed;
312 // If we got here, we didn't have enough space in the output buffer for the
313 // string. Try printing into a SmallVector that is resized to have enough
314 // space. Iterate until we win.
315 SmallVector<char, 128> V;
318 V.resize(NextBufferSize);
320 // Try formatting into the SmallVector.
321 size_t BytesUsed = Fmt.print(V.data(), NextBufferSize);
323 // If BytesUsed fit into the vector, we win.
324 if (BytesUsed <= NextBufferSize)
325 return write(V.data(), BytesUsed);
327 // Otherwise, try again with a new size.
328 assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?");
329 NextBufferSize = BytesUsed;
333 /// indent - Insert 'NumSpaces' spaces.
334 raw_ostream &raw_ostream::indent(unsigned NumSpaces) {
335 static const char Spaces[] = " "
339 // Usually the indentation is small, handle it with a fastpath.
340 if (NumSpaces < array_lengthof(Spaces))
341 return write(Spaces, NumSpaces);
344 unsigned NumToWrite = std::min(NumSpaces,
345 (unsigned)array_lengthof(Spaces)-1);
346 write(Spaces, NumToWrite);
347 NumSpaces -= NumToWrite;
353 //===----------------------------------------------------------------------===//
355 //===----------------------------------------------------------------------===//
357 // Out of line virtual method.
358 void format_object_base::home() {
361 //===----------------------------------------------------------------------===//
363 //===----------------------------------------------------------------------===//
365 /// raw_fd_ostream - Open the specified file for writing. If an error
366 /// occurs, information about the error is put into ErrorInfo, and the
367 /// stream should be immediately destroyed; the string will be empty
368 /// if no error occurred.
369 raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
370 unsigned Flags) : pos(0) {
371 // Verify that we don't have both "append" and "excl".
372 assert((!(Flags & F_Excl) || !(Flags & F_Append)) &&
373 "Cannot specify both 'excl' and 'append' file creation flags!");
377 // Handle "-" as stdout.
378 if (Filename[0] == '-' && Filename[1] == 0) {
380 // If user requested binary then put stdout into binary mode if
382 if (Flags & F_Binary)
383 sys::Program::ChangeStdoutToBinary();
388 int OpenFlags = O_WRONLY|O_CREAT;
390 if (Flags & F_Binary)
391 OpenFlags |= O_BINARY;
394 if (Flags & F_Append)
395 OpenFlags |= O_APPEND;
397 OpenFlags |= O_TRUNC;
401 FD = open(Filename, OpenFlags, 0664);
403 ErrorInfo = "Error opening output file '" + std::string(Filename) + "'";
410 raw_fd_ostream::~raw_fd_ostream() {
414 if (::close(FD) != 0)
419 void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
420 assert (FD >= 0 && "File already closed.");
422 if (::write(FD, Ptr, Size) != (ssize_t) Size)
426 void raw_fd_ostream::close() {
427 assert (ShouldClose);
430 if (::close(FD) != 0)
435 uint64_t raw_fd_ostream::seek(uint64_t off) {
437 pos = ::lseek(FD, off, SEEK_SET);
443 size_t raw_fd_ostream::preferred_buffer_size() {
444 #if !defined(_MSC_VER) && !defined(__MINGW32__) // Windows has no st_blksize.
445 assert(FD >= 0 && "File not yet open!");
447 if (fstat(FD, &statbuf) == 0) {
448 // If this is a terminal, don't use buffering. Line buffering
449 // would be a more traditional thing to do, but it's not worth
451 if (S_ISCHR(statbuf.st_mode) && isatty(FD))
453 // Return the preferred block size.
454 return statbuf.st_blksize;
458 return raw_ostream::preferred_buffer_size();
461 raw_ostream &raw_fd_ostream::changeColor(enum Colors colors, bool bold,
463 if (sys::Process::ColorNeedsFlush())
465 const char *colorcode =
466 (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg)
467 : sys::Process::OutputColor(colors, bold, bg);
469 size_t len = strlen(colorcode);
470 write(colorcode, len);
471 // don't account colors towards output characters
477 raw_ostream &raw_fd_ostream::resetColor() {
478 if (sys::Process::ColorNeedsFlush())
480 const char *colorcode = sys::Process::ResetColor();
482 size_t len = strlen(colorcode);
483 write(colorcode, len);
484 // don't account colors towards output characters
490 bool raw_fd_ostream::is_displayed() const {
491 return sys::Process::FileDescriptorIsDisplayed(FD);
494 //===----------------------------------------------------------------------===//
495 // raw_stdout/err_ostream
496 //===----------------------------------------------------------------------===//
498 // Set buffer settings to model stdout and stderr behavior.
499 // Set standard error to be unbuffered by default.
500 raw_stdout_ostream::raw_stdout_ostream():raw_fd_ostream(STDOUT_FILENO, false) {}
501 raw_stderr_ostream::raw_stderr_ostream():raw_fd_ostream(STDERR_FILENO, false,
504 // An out of line virtual method to provide a home for the class vtable.
505 void raw_stdout_ostream::handle() {}
506 void raw_stderr_ostream::handle() {}
508 /// outs() - This returns a reference to a raw_ostream for standard output.
509 /// Use it like: outs() << "foo" << "bar";
510 raw_ostream &llvm::outs() {
511 static raw_stdout_ostream S;
515 /// errs() - This returns a reference to a raw_ostream for standard error.
516 /// Use it like: errs() << "foo" << "bar";
517 raw_ostream &llvm::errs() {
518 static raw_stderr_ostream S;
522 /// nulls() - This returns a reference to a raw_ostream which discards output.
523 raw_ostream &llvm::nulls() {
524 static raw_null_ostream S;
529 //===----------------------------------------------------------------------===//
530 // raw_string_ostream
531 //===----------------------------------------------------------------------===//
533 raw_string_ostream::~raw_string_ostream() {
537 void raw_string_ostream::write_impl(const char *Ptr, size_t Size) {
538 OS.append(Ptr, Size);
541 //===----------------------------------------------------------------------===//
542 // raw_svector_ostream
543 //===----------------------------------------------------------------------===//
545 // The raw_svector_ostream implementation uses the SmallVector itself as the
546 // buffer for the raw_ostream. We guarantee that the raw_ostream buffer is
547 // always pointing past the end of the vector, but within the vector
548 // capacity. This allows raw_ostream to write directly into the correct place,
549 // and we only need to set the vector size when the data is flushed.
551 raw_svector_ostream::raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {
552 // Set up the initial external buffer. We make sure that the buffer has at
553 // least 128 bytes free; raw_ostream itself only requires 64, but we want to
554 // make sure that we don't grow the buffer unnecessarily on destruction (when
555 // the data is flushed). See the FIXME below.
556 OS.reserve(OS.size() + 128);
557 SetBuffer(OS.end(), OS.capacity() - OS.size());
560 raw_svector_ostream::~raw_svector_ostream() {
561 // FIXME: Prevent resizing during this flush().
565 void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) {
566 assert(Ptr == OS.end() && OS.size() + Size <= OS.capacity() &&
567 "Invalid write_impl() call!");
569 // We don't need to copy the bytes, just commit the bytes to the
571 OS.set_size(OS.size() + Size);
573 // Grow the vector if necessary.
574 if (OS.capacity() - OS.size() < 64)
575 OS.reserve(OS.capacity() * 2);
577 // Update the buffer position.
578 SetBuffer(OS.end(), OS.capacity() - OS.size());
581 uint64_t raw_svector_ostream::current_pos() { return OS.size(); }
583 StringRef raw_svector_ostream::str() {
585 return StringRef(OS.begin(), OS.size());
588 //===----------------------------------------------------------------------===//
590 //===----------------------------------------------------------------------===//
592 raw_null_ostream::~raw_null_ostream() {
594 // ~raw_ostream asserts that the buffer is empty. This isn't necessary
595 // with raw_null_ostream, but it's better to have raw_null_ostream follow
596 // the rules than to change the rules just for raw_null_ostream.
601 void raw_null_ostream::write_impl(const char *Ptr, size_t Size) {
604 uint64_t raw_null_ostream::current_pos() {