1 //===-- llvm/CodeGen/FormattedStream.h - Formatted streams ------*- 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 contains raw_ostream implementations for streams to do
11 // things like pretty-print comments.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_SUPPORT_FORMATTEDSTREAM_H
16 #define LLVM_SUPPORT_FORMATTEDSTREAM_H
18 #include "llvm/Support/raw_ostream.h"
22 /// formatted_raw_ostream - Formatted raw_fd_ostream to handle
23 /// asm-specific constructs.
25 class formatted_raw_ostream : public raw_ostream {
27 /// DELETE_STREAM - Tell the destructor to delete the held stream.
29 const static bool DELETE_STREAM = true;
30 /// PRESERVE_STREAM - Tell the destructor to not delete the held
33 const static bool PRESERVE_STREAM = false;
36 /// TheStream - The real stream we output to. We set it to be
37 /// unbuffered, since we're already doing our own buffering.
39 raw_ostream *TheStream;
40 /// DeleteStream - Do we need to delete TheStream in the
45 /// Column - The current output column of the stream. The column
46 /// scheme is zero-based.
50 virtual void write_impl(const char *Ptr, size_t Size) {
51 ComputeColumn(Ptr, Size);
52 TheStream->write(Ptr, Size);
55 /// current_pos - Return the current position within the stream,
56 /// not counting the bytes currently in the buffer.
57 virtual uint64_t current_pos() {
58 // This has the same effect as calling TheStream.current_pos(),
59 // but that interface is private.
60 return TheStream->tell() - TheStream->GetNumBytesInBuffer();
63 /// ComputeColumn - Examine the current output and figure out
64 /// which column we end up in after output.
66 void ComputeColumn(const char *Ptr, size_t Size);
69 /// formatted_raw_ostream - Open the specified file for
70 /// writing. If an error occurs, information about the error is
71 /// put into ErrorInfo, and the stream should be immediately
72 /// destroyed; the string will be empty if no error occurred.
74 /// As a side effect, the given Stream is set to be Unbuffered.
75 /// This is because formatted_raw_ostream does its own buffering,
76 /// so it doesn't want another layer of buffering to be happening
79 formatted_raw_ostream(raw_ostream &Stream, bool Delete = false)
80 : raw_ostream(), TheStream(0), DeleteStream(false), Column(0) {
81 setStream(Stream, Delete);
83 explicit formatted_raw_ostream()
84 : raw_ostream(), TheStream(0), DeleteStream(false), Column(0) {}
86 ~formatted_raw_ostream() {
91 void setStream(raw_ostream &Stream, bool Delete = false) {
96 DeleteStream = Delete;
98 // This formatted_raw_ostream inherits from raw_ostream, so it'll do its
99 // own buffering, and it doesn't need or want TheStream to do another
100 // layer of buffering underneath. Resize the buffer to what TheStream
101 // had been using, and tell TheStream not to do its own buffering.
103 if (size_t BufferSize = TheStream->GetNumBytesInBuffer())
104 SetBufferSize(BufferSize);
105 TheStream->SetUnbuffered();
108 /// PadToColumn - Align the output to some column number.
110 /// \param NewCol - The column to move to.
111 /// \param MinPad - The minimum space to give after the most
112 /// recent I/O, even if the current column + minpad > newcol.
114 void PadToColumn(unsigned NewCol, unsigned MinPad = 0);
117 /// fouts() - This returns a reference to a formatted_raw_ostream for
118 /// standard output. Use it like: fouts() << "foo" << "bar";
119 formatted_raw_ostream &fouts();
121 /// ferrs() - This returns a reference to a formatted_raw_ostream for
122 /// standard error. Use it like: ferrs() << "foo" << "bar";
123 formatted_raw_ostream &ferrs();
125 } // end llvm namespace