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 this->operator<<(ftostr(N));
218 void raw_ostream::flush_nonempty() {
219 assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty.");
220 size_t Length = OutBufCur - OutBufStart;
221 OutBufCur = OutBufStart;
222 write_impl(OutBufStart, Length);
225 raw_ostream &raw_ostream::write(unsigned char C) {
226 // Group exceptional cases into a single branch.
227 if (BUILTIN_EXPECT(OutBufCur >= OutBufEnd, false)) {
228 if (BUILTIN_EXPECT(!OutBufStart, false)) {
229 if (BufferMode == Unbuffered) {
230 write_impl(reinterpret_cast<char*>(&C), 1);
233 // Set up a buffer and start over.
245 raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) {
246 // Group exceptional cases into a single branch.
247 if (BUILTIN_EXPECT(OutBufCur+Size > OutBufEnd, false)) {
248 if (BUILTIN_EXPECT(!OutBufStart, false)) {
249 if (BufferMode == Unbuffered) {
250 write_impl(Ptr, Size);
253 // Set up a buffer and start over.
255 return write(Ptr, Size);
258 // Write out the data in buffer-sized blocks until the remainder
259 // fits within the buffer.
261 size_t NumBytes = OutBufEnd - OutBufCur;
262 copy_to_buffer(Ptr, NumBytes);
266 } while (OutBufCur+Size > OutBufEnd);
269 copy_to_buffer(Ptr, Size);
274 void raw_ostream::copy_to_buffer(const char *Ptr, size_t Size) {
275 assert(Size <= size_t(OutBufEnd - OutBufCur) && "Buffer overrun!");
277 // Handle short strings specially, memcpy isn't very good at very short
280 case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH
281 case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH
282 case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH
283 case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH
286 memcpy(OutBufCur, Ptr, Size);
294 raw_ostream &raw_ostream::operator<<(const format_object_base &Fmt) {
295 // If we have more than a few bytes left in our output buffer, try
296 // formatting directly onto its end.
297 size_t NextBufferSize = 127;
298 size_t BufferBytesLeft = OutBufEnd - OutBufCur;
299 if (BufferBytesLeft > 3) {
300 size_t BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft);
302 // Common case is that we have plenty of space.
303 if (BytesUsed <= BufferBytesLeft) {
304 OutBufCur += BytesUsed;
308 // Otherwise, we overflowed and the return value tells us the size to try
310 NextBufferSize = BytesUsed;
313 // If we got here, we didn't have enough space in the output buffer for the
314 // string. Try printing into a SmallVector that is resized to have enough
315 // space. Iterate until we win.
316 SmallVector<char, 128> V;
319 V.resize(NextBufferSize);
321 // Try formatting into the SmallVector.
322 size_t BytesUsed = Fmt.print(V.data(), NextBufferSize);
324 // If BytesUsed fit into the vector, we win.
325 if (BytesUsed <= NextBufferSize)
326 return write(V.data(), BytesUsed);
328 // Otherwise, try again with a new size.
329 assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?");
330 NextBufferSize = BytesUsed;
334 /// indent - Insert 'NumSpaces' spaces.
335 raw_ostream &raw_ostream::indent(unsigned NumSpaces) {
336 static const char Spaces[] = " "
340 // Usually the indentation is small, handle it with a fastpath.
341 if (NumSpaces < array_lengthof(Spaces))
342 return write(Spaces, NumSpaces);
345 unsigned NumToWrite = std::min(NumSpaces,
346 (unsigned)array_lengthof(Spaces)-1);
347 write(Spaces, NumToWrite);
348 NumSpaces -= NumToWrite;
354 //===----------------------------------------------------------------------===//
356 //===----------------------------------------------------------------------===//
358 // Out of line virtual method.
359 void format_object_base::home() {
362 //===----------------------------------------------------------------------===//
364 //===----------------------------------------------------------------------===//
366 /// raw_fd_ostream - Open the specified file for writing. If an error
367 /// occurs, information about the error is put into ErrorInfo, and the
368 /// stream should be immediately destroyed; the string will be empty
369 /// if no error occurred.
370 raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
371 unsigned Flags) : pos(0) {
372 // Verify that we don't have both "append" and "excl".
373 assert((!(Flags & F_Excl) || !(Flags & F_Append)) &&
374 "Cannot specify both 'excl' and 'append' file creation flags!");
378 // Handle "-" as stdout.
379 if (Filename[0] == '-' && Filename[1] == 0) {
381 // If user requested binary then put stdout into binary mode if
383 if (Flags & F_Binary)
384 sys::Program::ChangeStdoutToBinary();
389 int OpenFlags = O_WRONLY|O_CREAT;
391 if (Flags & F_Binary)
392 OpenFlags |= O_BINARY;
395 if (Flags & F_Append)
396 OpenFlags |= O_APPEND;
398 OpenFlags |= O_TRUNC;
402 FD = open(Filename, OpenFlags, 0664);
404 ErrorInfo = "Error opening output file '" + std::string(Filename) + "'";
411 raw_fd_ostream::~raw_fd_ostream() {
415 if (::close(FD) != 0)
420 void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
421 assert (FD >= 0 && "File already closed.");
423 if (::write(FD, Ptr, Size) != (ssize_t) Size)
427 void raw_fd_ostream::close() {
428 assert (ShouldClose);
431 if (::close(FD) != 0)
436 uint64_t raw_fd_ostream::seek(uint64_t off) {
438 pos = ::lseek(FD, off, SEEK_SET);
444 size_t raw_fd_ostream::preferred_buffer_size() {
445 #if !defined(_MSC_VER) && !defined(__MINGW32__) // Windows has no st_blksize.
446 assert(FD >= 0 && "File not yet open!");
448 if (fstat(FD, &statbuf) == 0) {
449 // If this is a terminal, don't use buffering. Line buffering
450 // would be a more traditional thing to do, but it's not worth
452 if (S_ISCHR(statbuf.st_mode) && isatty(FD))
454 // Return the preferred block size.
455 return statbuf.st_blksize;
459 return raw_ostream::preferred_buffer_size();
462 raw_ostream &raw_fd_ostream::changeColor(enum Colors colors, bool bold,
464 if (sys::Process::ColorNeedsFlush())
466 const char *colorcode =
467 (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg)
468 : sys::Process::OutputColor(colors, bold, bg);
470 size_t len = strlen(colorcode);
471 write(colorcode, len);
472 // don't account colors towards output characters
478 raw_ostream &raw_fd_ostream::resetColor() {
479 if (sys::Process::ColorNeedsFlush())
481 const char *colorcode = sys::Process::ResetColor();
483 size_t len = strlen(colorcode);
484 write(colorcode, len);
485 // don't account colors towards output characters
491 bool raw_fd_ostream::is_displayed() const {
492 return sys::Process::FileDescriptorIsDisplayed(FD);
495 //===----------------------------------------------------------------------===//
496 // raw_stdout/err_ostream
497 //===----------------------------------------------------------------------===//
499 // Set buffer settings to model stdout and stderr behavior.
500 // Set standard error to be unbuffered by default.
501 raw_stdout_ostream::raw_stdout_ostream():raw_fd_ostream(STDOUT_FILENO, false) {}
502 raw_stderr_ostream::raw_stderr_ostream():raw_fd_ostream(STDERR_FILENO, false,
505 // An out of line virtual method to provide a home for the class vtable.
506 void raw_stdout_ostream::handle() {}
507 void raw_stderr_ostream::handle() {}
509 /// outs() - This returns a reference to a raw_ostream for standard output.
510 /// Use it like: outs() << "foo" << "bar";
511 raw_ostream &llvm::outs() {
512 static raw_stdout_ostream S;
516 /// errs() - This returns a reference to a raw_ostream for standard error.
517 /// Use it like: errs() << "foo" << "bar";
518 raw_ostream &llvm::errs() {
519 static raw_stderr_ostream S;
523 /// nulls() - This returns a reference to a raw_ostream which discards output.
524 raw_ostream &llvm::nulls() {
525 static raw_null_ostream S;
530 //===----------------------------------------------------------------------===//
531 // raw_string_ostream
532 //===----------------------------------------------------------------------===//
534 raw_string_ostream::~raw_string_ostream() {
538 void raw_string_ostream::write_impl(const char *Ptr, size_t Size) {
539 OS.append(Ptr, Size);
542 //===----------------------------------------------------------------------===//
543 // raw_svector_ostream
544 //===----------------------------------------------------------------------===//
546 // The raw_svector_ostream implementation uses the SmallVector itself as the
547 // buffer for the raw_ostream. We guarantee that the raw_ostream buffer is
548 // always pointing past the end of the vector, but within the vector
549 // capacity. This allows raw_ostream to write directly into the correct place,
550 // and we only need to set the vector size when the data is flushed.
552 raw_svector_ostream::raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {
553 // Set up the initial external buffer. We make sure that the buffer has at
554 // least 128 bytes free; raw_ostream itself only requires 64, but we want to
555 // make sure that we don't grow the buffer unnecessarily on destruction (when
556 // the data is flushed). See the FIXME below.
557 OS.reserve(OS.size() + 128);
558 SetBuffer(OS.end(), OS.capacity() - OS.size());
561 raw_svector_ostream::~raw_svector_ostream() {
562 // FIXME: Prevent resizing during this flush().
566 void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) {
567 assert(Ptr == OS.end() && OS.size() + Size <= OS.capacity() &&
568 "Invalid write_impl() call!");
570 // We don't need to copy the bytes, just commit the bytes to the
572 OS.set_size(OS.size() + Size);
574 // Grow the vector if necessary.
575 if (OS.capacity() - OS.size() < 64)
576 OS.reserve(OS.capacity() * 2);
578 // Update the buffer position.
579 SetBuffer(OS.end(), OS.capacity() - OS.size());
582 uint64_t raw_svector_ostream::current_pos() { return OS.size(); }
584 StringRef raw_svector_ostream::str() {
586 return StringRef(OS.begin(), OS.size());
589 //===----------------------------------------------------------------------===//
591 //===----------------------------------------------------------------------===//
593 raw_null_ostream::~raw_null_ostream() {
595 // ~raw_ostream asserts that the buffer is empty. This isn't necessary
596 // with raw_null_ostream, but it's better to have raw_null_ostream follow
597 // the rules than to change the rules just for raw_null_ostream.
602 void raw_null_ostream::write_impl(const char *Ptr, size_t Size) {
605 uint64_t raw_null_ostream::current_pos() {