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"
24 class format_object_base;
26 class SmallVectorImpl;
28 /// raw_ostream - This class implements an extremely fast bulk output stream
29 /// that can *only* output to a stream. It does not support seeking, reopening,
30 /// rewinding, line buffered disciplines etc. It is a simple buffer that outputs
31 /// a chunk at a time.
34 /// \invariant { The buffer is uninitialized (OutBufStart,
35 /// OutBufEnd, and OutBufCur are non-zero), or none of them are zero
36 /// and there are at least 64 total bytes in the buffer. }
38 char *OutBufStart, *OutBufEnd, *OutBufCur;
42 explicit raw_ostream(bool unbuffered=false) : Unbuffered(unbuffered) {
43 // Start out ready to flush.
44 OutBufStart = OutBufEnd = OutBufCur = 0;
47 virtual ~raw_ostream() {
48 delete [] OutBufStart;
51 //===--------------------------------------------------------------------===//
52 // Configuration Interface
53 //===--------------------------------------------------------------------===//
55 /// SetBufferSize - Set the internal buffer size to the specified amount
56 /// instead of the default.
57 void SetBufferSize(unsigned Size) {
59 "Buffer size must be somewhat large for invariants to hold");
62 delete [] OutBufStart;
63 OutBufStart = new char[Size];
64 OutBufEnd = OutBufStart+Size;
65 OutBufCur = OutBufStart;
68 /// SetUnbuffered - Set the streams buffering status. When
69 /// unbuffered the stream will flush after every write. This routine
70 /// will also flush the buffer immediately when the stream is being
71 /// set to unbuffered.
72 void SetUnbuffered(bool unbuffered) {
73 Unbuffered = unbuffered;
78 unsigned GetNumBytesInBuffer() const {
79 return OutBufCur - OutBufStart;
82 //===--------------------------------------------------------------------===//
83 // Data Output Interface
84 //===--------------------------------------------------------------------===//
87 if (OutBufCur != OutBufStart)
91 raw_ostream &operator<<(char C) {
92 if (OutBufCur >= OutBufEnd)
100 raw_ostream &operator<<(unsigned char C) {
101 if (OutBufCur >= OutBufEnd)
109 raw_ostream &operator<<(signed char C) {
110 if (OutBufCur >= OutBufEnd)
118 raw_ostream &operator<<(const char *Str) {
119 return write(Str, strlen(Str));
122 raw_ostream &operator<<(const std::string& Str) {
123 return write(Str.data(), Str.length());
126 raw_ostream &operator<<(unsigned long N);
127 raw_ostream &operator<<(long N);
128 raw_ostream &operator<<(unsigned long long N);
129 raw_ostream &operator<<(long long N);
130 raw_ostream &operator<<(const void *P);
131 raw_ostream &operator<<(unsigned int N) {
132 return this->operator<<(static_cast<unsigned long>(N));
135 raw_ostream &operator<<(int N) {
136 return this->operator<<(static_cast<long>(N));
139 raw_ostream &operator<<(double N) {
140 return this->operator<<(ftostr(N));
143 raw_ostream &write(unsigned char C);
144 raw_ostream &write(const char *Ptr, unsigned Size);
146 // Formatted output, see the format() function in Support/Format.h.
147 raw_ostream &operator<<(const format_object_base &Fmt);
149 //===--------------------------------------------------------------------===//
150 // Subclass Interface
151 //===--------------------------------------------------------------------===//
154 /// write_impl - The is the piece of the class that is implemented
155 /// by subclasses. This writes the \args Size bytes starting at
156 /// \arg Ptr to the underlying stream.
158 /// \invariant { Size > 0 }
159 virtual void write_impl(const char *Ptr, unsigned Size) = 0;
161 // An out of line virtual method to provide a home for the class vtable.
162 virtual void handle();
164 //===--------------------------------------------------------------------===//
166 //===--------------------------------------------------------------------===//
168 /// flush_nonempty - Flush the current buffer, which is known to be
169 /// non-empty. This outputs the currently buffered data and resets
170 /// the buffer to empty.
171 void flush_nonempty();
174 //===----------------------------------------------------------------------===//
175 // File Output Streams
176 //===----------------------------------------------------------------------===//
178 /// raw_fd_ostream - A raw_ostream that writes to a file descriptor.
180 class raw_fd_ostream : public raw_ostream {
185 /// write_impl - See raw_ostream::write_impl.
186 virtual void write_impl(const char *Ptr, unsigned Size);
188 /// raw_fd_ostream - Open the specified file for writing. If an
189 /// error occurs, information about the error is put into ErrorInfo,
190 /// and the stream should be immediately destroyed; the string will
191 /// be empty if no error occurred.
193 /// \param Filename - The file to open. If this is "-" then the
194 /// stream will use stdout instead.
195 /// \param Binary - The file should be opened in binary mode on
196 /// platforms that support this distinction.
197 raw_fd_ostream(const char *Filename, bool Binary, std::string &ErrorInfo);
199 /// raw_fd_ostream ctor - FD is the file descriptor that this writes to. If
200 /// ShouldClose is true, this closes the file when the stream is destroyed.
201 raw_fd_ostream(int fd, bool shouldClose,
202 bool unbuffered=false) : raw_ostream(unbuffered), FD(fd),
203 ShouldClose(shouldClose) {}
207 /// close - Manually flush the stream and close the file.
210 /// tell - Return the current offset with the file.
211 uint64_t tell() { return pos + GetNumBytesInBuffer(); }
213 /// seek - Flushes the stream and repositions the underlying file descriptor
214 /// positition to the offset specified from the beginning of the file.
215 uint64_t seek(uint64_t off);
218 /// raw_stdout_ostream - This is a stream that always prints to stdout.
220 class raw_stdout_ostream : public raw_fd_ostream {
221 // An out of line virtual method to provide a home for the class vtable.
222 virtual void handle();
224 raw_stdout_ostream();
227 /// raw_stderr_ostream - This is a stream that always prints to stderr.
229 class raw_stderr_ostream : public raw_fd_ostream {
230 // An out of line virtual method to provide a home for the class vtable.
231 virtual void handle();
233 raw_stderr_ostream();
236 /// outs() - This returns a reference to a raw_ostream for standard output.
237 /// Use it like: outs() << "foo" << "bar";
240 /// errs() - This returns a reference to a raw_ostream for standard error.
241 /// Use it like: errs() << "foo" << "bar";
245 //===----------------------------------------------------------------------===//
246 // Output Stream Adaptors
247 //===----------------------------------------------------------------------===//
249 /// raw_os_ostream - A raw_ostream that writes to an std::ostream. This is a
250 /// simple adaptor class.
251 class raw_os_ostream : public raw_ostream {
254 /// write_impl - See raw_ostream::write_impl.
255 virtual void write_impl(const char *Ptr, unsigned Size);
257 raw_os_ostream(std::ostream &O) : OS(O) {}
261 /// raw_string_ostream - A raw_ostream that writes to an std::string. This is a
262 /// simple adaptor class.
263 class raw_string_ostream : public raw_ostream {
266 /// write_impl - See raw_ostream::write_impl.
267 virtual void write_impl(const char *Ptr, unsigned Size);
269 raw_string_ostream(std::string &O) : OS(O) {}
270 ~raw_string_ostream();
272 /// str - Flushes the stream contents to the target string and returns
273 /// the string's reference.
280 /// raw_svector_ostream - A raw_ostream that writes to an SmallVector or
281 /// SmallString. This is a simple adaptor class.
282 class raw_svector_ostream : public raw_ostream {
283 SmallVectorImpl<char> &OS;
285 /// write_impl - See raw_ostream::write_impl.
286 virtual void write_impl(const char *Ptr, unsigned Size);
288 raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {}
289 ~raw_svector_ostream();
292 } // end llvm namespace