1 //===--- raw_ostream.h - Raw output stream ----------------------*- C++ -*-===//
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 file defines the raw_ostream class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_SUPPORT_RAW_OSTREAM_H
15 #define LLVM_SUPPORT_RAW_OSTREAM_H
17 #include "llvm/ADT/StringExtras.h"
18 #include "llvm/ADT/StringRef.h"
25 class format_object_base;
27 class SmallVectorImpl;
29 /// raw_ostream - This class implements an extremely fast bulk output stream
30 /// that can *only* output to a stream. It does not support seeking, reopening,
31 /// rewinding, line buffered disciplines etc. It is a simple buffer that outputs
32 /// a chunk at a time.
35 /// The buffer is handled in such a way that the buffer is
36 /// uninitialized, unbuffered, or out of space when OutBufCur >=
37 /// OutBufEnd. Thus a single comparison suffices to determine if we
38 /// need to take the slow path to write a single character.
40 /// The buffer is in one of three states:
41 /// 1. Unbuffered (Unbuffered == true)
42 /// 1. Uninitialized (Unbuffered == false && OutBufStart == 0).
43 /// 2. Buffered (Unbuffered == false && OutBufStart != 0 &&
44 /// OutBufEnd - OutBufStart >= 64).
45 char *OutBufStart, *OutBufEnd, *OutBufCur;
48 /// Error This flag is true if an error of any kind has been detected.
53 // color order matches ANSI escape sequence, don't change
66 explicit raw_ostream(bool unbuffered=false)
67 : Unbuffered(unbuffered), Error(false) {
68 // Start out ready to flush.
69 OutBufStart = OutBufEnd = OutBufCur = 0;
72 virtual ~raw_ostream();
74 /// tell - Return the current offset with the file.
75 uint64_t tell() { return current_pos() + GetNumBytesInBuffer(); }
77 /// has_error - Return the value of the flag in this raw_ostream indicating
78 /// whether an output error has been encountered.
79 bool has_error() const {
83 /// clear_error - Set the flag read by has_error() to false. If the error
84 /// flag is set at the time when this raw_ostream's destructor is called,
85 /// llvm_report_error is called to report the error. Use clear_error()
86 /// after handling the error to avoid this behavior.
91 //===--------------------------------------------------------------------===//
92 // Configuration Interface
93 //===--------------------------------------------------------------------===//
95 /// SetBufferSize - Set the internal buffer size to the specified amount
96 /// instead of the default.
97 void SetBufferSize(size_t Size=4096);
99 size_t GetBufferSize() const {
100 return OutBufEnd - OutBufStart;
103 /// SetUnbuffered - Set the streams buffering status. When
104 /// unbuffered the stream will flush after every write. This routine
105 /// will also flush the buffer immediately when the stream is being
106 /// set to unbuffered.
107 void SetUnbuffered();
109 size_t GetNumBytesInBuffer() const {
110 return OutBufCur - OutBufStart;
113 //===--------------------------------------------------------------------===//
114 // Data Output Interface
115 //===--------------------------------------------------------------------===//
118 if (OutBufCur != OutBufStart)
122 raw_ostream &operator<<(char C) {
123 if (OutBufCur >= OutBufEnd)
129 raw_ostream &operator<<(unsigned char C) {
130 if (OutBufCur >= OutBufEnd)
136 raw_ostream &operator<<(signed char C) {
137 if (OutBufCur >= OutBufEnd)
143 raw_ostream &operator<<(const StringRef &Str) {
144 // Inline fast path, particularly for strings with a known length.
145 size_t Size = Str.size();
147 // Make sure we can use the fast path.
148 if (OutBufCur+Size > OutBufEnd)
149 return write(Str.data(), Size);
151 memcpy(OutBufCur, Str.data(), Size);
156 raw_ostream &operator<<(const char *Str) {
157 // Inline fast path, particulary for constant strings where a sufficiently
158 // smart compiler will simplify strlen.
160 this->operator<<(StringRef(Str));
164 raw_ostream &operator<<(const std::string& Str) {
165 write(Str.data(), Str.length());
169 raw_ostream &operator<<(unsigned long N);
170 raw_ostream &operator<<(long N);
171 raw_ostream &operator<<(unsigned long long N);
172 raw_ostream &operator<<(long long N);
173 raw_ostream &operator<<(const void *P);
174 raw_ostream &operator<<(unsigned int N) {
175 this->operator<<(static_cast<unsigned long>(N));
179 raw_ostream &operator<<(int N) {
180 this->operator<<(static_cast<long>(N));
184 raw_ostream &operator<<(double N) {
185 this->operator<<(ftostr(N));
189 /// write_hex - Output \arg N in hexadecimal, without any prefix or padding.
190 raw_ostream &write_hex(unsigned long long N);
192 raw_ostream &write(unsigned char C);
193 raw_ostream &write(const char *Ptr, size_t Size);
195 // Formatted output, see the format() function in Support/Format.h.
196 raw_ostream &operator<<(const format_object_base &Fmt);
198 /// Changes the foreground color of text that will be output from this point
200 /// @param colors ANSI color to use, the special SAVEDCOLOR can be used to
201 /// change only the bold attribute, and keep colors untouched
202 /// @param bold bold/brighter text, default false
203 /// @param bg if true change the background, default: change foreground
204 /// @returns itself so it can be used within << invocations
205 virtual raw_ostream &changeColor(enum Colors colors, bool bold=false,
206 bool bg=false) { return *this; }
208 /// Resets the colors to terminal defaults. Call this when you are done
209 /// outputting colored text, or before program exit.
210 virtual raw_ostream &resetColor() { return *this; }
212 //===--------------------------------------------------------------------===//
213 // Subclass Interface
214 //===--------------------------------------------------------------------===//
217 /// write_impl - The is the piece of the class that is implemented
218 /// by subclasses. This writes the \args Size bytes starting at
219 /// \arg Ptr to the underlying stream.
221 /// \invariant { Size > 0 }
222 virtual void write_impl(const char *Ptr, size_t Size) = 0;
224 // An out of line virtual method to provide a home for the class vtable.
225 virtual void handle();
227 /// current_pos - Return the current position within the stream, not
228 /// counting the bytes currently in the buffer.
229 virtual uint64_t current_pos() = 0;
232 /// error_detected - Set the flag indicating that an output error has
233 /// been encountered.
234 void error_detected() { Error = true; }
236 typedef char * iterator;
237 iterator begin() { return OutBufStart; }
238 iterator end() { return OutBufCur; }
240 //===--------------------------------------------------------------------===//
242 //===--------------------------------------------------------------------===//
244 /// flush_nonempty - Flush the current buffer, which is known to be
245 /// non-empty. This outputs the currently buffered data and resets
246 /// the buffer to empty.
247 void flush_nonempty();
249 /// copy_to_buffer - Copy data into the buffer. Size must not be
250 /// greater than the number of unused bytes in the buffer.
251 void copy_to_buffer(const char *Ptr, size_t Size);
254 //===----------------------------------------------------------------------===//
255 // File Output Streams
256 //===----------------------------------------------------------------------===//
258 /// raw_fd_ostream - A raw_ostream that writes to a file descriptor.
260 class raw_fd_ostream : public raw_ostream {
265 /// write_impl - See raw_ostream::write_impl.
266 virtual void write_impl(const char *Ptr, size_t Size);
268 /// current_pos - Return the current position within the stream, not
269 /// counting the bytes currently in the buffer.
270 virtual uint64_t current_pos() { return pos; }
273 /// raw_fd_ostream - Open the specified file for writing. If an
274 /// error occurs, information about the error is put into ErrorInfo,
275 /// and the stream should be immediately destroyed; the string will
276 /// be empty if no error occurred.
278 /// \param Filename - The file to open. If this is "-" then the
279 /// stream will use stdout instead.
280 /// \param Binary - The file should be opened in binary mode on
281 /// platforms that support this distinction.
282 /// \param Force - Don't consider the case where the file already
283 /// exists to be an error.
284 raw_fd_ostream(const char *Filename, bool Binary, bool Force,
285 std::string &ErrorInfo);
287 /// raw_fd_ostream ctor - FD is the file descriptor that this writes to. If
288 /// ShouldClose is true, this closes the file when the stream is destroyed.
289 raw_fd_ostream(int fd, bool shouldClose,
290 bool unbuffered=false) : raw_ostream(unbuffered), FD(fd),
291 ShouldClose(shouldClose) {}
295 /// close - Manually flush the stream and close the file.
298 /// tell - Return the current offset with the file.
299 uint64_t tell() { return pos + GetNumBytesInBuffer(); }
301 /// seek - Flushes the stream and repositions the underlying file descriptor
302 /// positition to the offset specified from the beginning of the file.
303 uint64_t seek(uint64_t off);
305 virtual raw_ostream &changeColor(enum Colors colors, bool bold=false,
307 virtual raw_ostream &resetColor();
310 /// raw_stdout_ostream - This is a stream that always prints to stdout.
312 class raw_stdout_ostream : public raw_fd_ostream {
313 // An out of line virtual method to provide a home for the class vtable.
314 virtual void handle();
316 raw_stdout_ostream();
319 /// raw_stderr_ostream - This is a stream that always prints to stderr.
321 class raw_stderr_ostream : public raw_fd_ostream {
322 // An out of line virtual method to provide a home for the class vtable.
323 virtual void handle();
325 raw_stderr_ostream();
328 /// outs() - This returns a reference to a raw_ostream for standard output.
329 /// Use it like: outs() << "foo" << "bar";
332 /// errs() - This returns a reference to a raw_ostream for standard error.
333 /// Use it like: errs() << "foo" << "bar";
336 /// nulls() - This returns a reference to a raw_ostream which simply discards
338 raw_ostream &nulls();
340 //===----------------------------------------------------------------------===//
341 // Output Stream Adaptors
342 //===----------------------------------------------------------------------===//
344 /// raw_os_ostream - A raw_ostream that writes to an std::ostream. This is a
345 /// simple adaptor class. It does not check for output errors; clients should
346 /// use the underlying stream to detect errors.
347 class raw_os_ostream : public raw_ostream {
350 /// write_impl - See raw_ostream::write_impl.
351 virtual void write_impl(const char *Ptr, size_t Size);
353 /// current_pos - Return the current position within the stream, not
354 /// counting the bytes currently in the buffer.
355 virtual uint64_t current_pos();
358 raw_os_ostream(std::ostream &O) : OS(O) {}
361 /// tell - Return the current offset with the stream.
365 /// raw_string_ostream - A raw_ostream that writes to an std::string. This is a
366 /// simple adaptor class. This class does not encounter output errors.
367 class raw_string_ostream : public raw_ostream {
370 /// write_impl - See raw_ostream::write_impl.
371 virtual void write_impl(const char *Ptr, size_t Size);
373 /// current_pos - Return the current position within the stream, not
374 /// counting the bytes currently in the buffer.
375 virtual uint64_t current_pos() { return OS.size(); }
377 explicit raw_string_ostream(std::string &O) : OS(O) {}
378 ~raw_string_ostream();
380 /// tell - Return the current offset with the stream.
381 uint64_t tell() { return OS.size() + GetNumBytesInBuffer(); }
383 /// str - Flushes the stream contents to the target string and returns
384 /// the string's reference.
391 /// raw_svector_ostream - A raw_ostream that writes to an SmallVector or
392 /// SmallString. This is a simple adaptor class. This class does not
393 /// encounter output errors.
394 class raw_svector_ostream : public raw_ostream {
395 SmallVectorImpl<char> &OS;
397 /// write_impl - See raw_ostream::write_impl.
398 virtual void write_impl(const char *Ptr, size_t Size);
400 /// current_pos - Return the current position within the stream, not
401 /// counting the bytes currently in the buffer.
402 virtual uint64_t current_pos();
404 explicit raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {}
405 ~raw_svector_ostream();
407 /// tell - Return the current offset with the stream.
411 /// raw_null_ostream - A raw_ostream that discards all output.
412 class raw_null_ostream : public raw_ostream {
413 /// write_impl - See raw_ostream::write_impl.
414 virtual void write_impl(const char *Ptr, size_t size);
416 /// current_pos - Return the current position within the stream, not
417 /// counting the bytes currently in the buffer.
418 virtual uint64_t current_pos();
421 explicit raw_null_ostream() {}
425 } // end llvm namespace