llvm-6502/include/llvm/Support/raw_ostream.h

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//===--- raw_ostream.h - Raw output stream ----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the raw_ostream class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_RAW_OSTREAM_H
#define LLVM_SUPPORT_RAW_OSTREAM_H
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include <cassert>
#include <cstring>
#include <string>
#include <iosfwd>
namespace llvm {
class format_object_base;
template <typename T>
class SmallVectorImpl;
/// raw_ostream - This class implements an extremely fast bulk output stream
/// that can *only* output to a stream. It does not support seeking, reopening,
/// rewinding, line buffered disciplines etc. It is a simple buffer that outputs
/// a chunk at a time.
class raw_ostream {
private:
// Do not implement. raw_ostream is noncopyable.
void operator=(const raw_ostream &);
raw_ostream(const raw_ostream &);
/// The buffer is handled in such a way that the buffer is
/// uninitialized, unbuffered, or out of space when OutBufCur >=
/// OutBufEnd. Thus a single comparison suffices to determine if we
/// need to take the slow path to write a single character.
///
/// The buffer is in one of three states:
/// 1. Unbuffered (BufferMode == Unbuffered)
/// 1. Uninitialized (BufferMode != Unbuffered && OutBufStart == 0).
/// 2. Buffered (BufferMode != Unbuffered && OutBufStart != 0 &&
/// OutBufEnd - OutBufStart >= 64).
///
/// If buffered, then the raw_ostream owns the buffer if (BufferMode ==
/// InternalBuffer); otherwise the buffer has been set via SetBuffer and is
/// managed by the subclass.
///
/// If a subclass installs an external buffer using SetBuffer then it can wait
/// for a \see write_impl() call to handle the data which has been put into
/// this buffer.
char *OutBufStart, *OutBufEnd, *OutBufCur;
enum BufferKind {
Unbuffered = 0,
InternalBuffer,
ExternalBuffer
} BufferMode;
/// Error This flag is true if an error of any kind has been detected.
///
bool Error;
public:
// color order matches ANSI escape sequence, don't change
enum Colors {
BLACK=0,
RED,
GREEN,
YELLOW,
BLUE,
MAGENTA,
CYAN,
WHITE,
SAVEDCOLOR
};
explicit raw_ostream(bool unbuffered=false)
: BufferMode(unbuffered ? Unbuffered : InternalBuffer), Error(false) {
// Start out ready to flush.
OutBufStart = OutBufEnd = OutBufCur = 0;
}
virtual ~raw_ostream();
/// tell - Return the current offset with the file.
uint64_t tell() { return current_pos() + GetNumBytesInBuffer(); }
/// has_error - Return the value of the flag in this raw_ostream indicating
/// whether an output error has been encountered.
bool has_error() const {
return Error;
}
/// clear_error - Set the flag read by has_error() to false. If the error
/// flag is set at the time when this raw_ostream's destructor is called,
/// llvm_report_error is called to report the error. Use clear_error()
/// after handling the error to avoid this behavior.
void clear_error() {
Error = false;
}
//===--------------------------------------------------------------------===//
// Configuration Interface
//===--------------------------------------------------------------------===//
/// SetBuffered - Set the stream to be buffered, with an automatically
/// determined buffer size.
void SetBuffered();
/// SetBufferSize - Set the stream to be buffered, using the
/// specified buffer size.
void SetBufferSize(size_t Size) {
flush();
SetBufferAndMode(new char[Size], Size, InternalBuffer);
}
size_t GetBufferSize() {
// If we're supposed to be buffered but haven't actually gotten around
// to allocating the buffer yet, return the value that would be used.
if (BufferMode != Unbuffered && OutBufStart == 0)
return preferred_buffer_size();
// Otherwise just return the size of the allocated buffer.
return OutBufEnd - OutBufStart;
}
/// SetUnbuffered - Set the stream to be unbuffered. When
/// unbuffered, the stream will flush after every write. This routine
/// will also flush the buffer immediately when the stream is being
/// set to unbuffered.
void SetUnbuffered() {
flush();
SetBufferAndMode(0, 0, Unbuffered);
}
size_t GetNumBytesInBuffer() const {
return OutBufCur - OutBufStart;
}
//===--------------------------------------------------------------------===//
// Data Output Interface
//===--------------------------------------------------------------------===//
void flush() {
if (OutBufCur != OutBufStart)
flush_nonempty();
}
raw_ostream &operator<<(char C) {
if (OutBufCur >= OutBufEnd)
return write(C);
*OutBufCur++ = C;
return *this;
}
raw_ostream &operator<<(unsigned char C) {
if (OutBufCur >= OutBufEnd)
return write(C);
*OutBufCur++ = C;
return *this;
}
raw_ostream &operator<<(signed char C) {
if (OutBufCur >= OutBufEnd)
return write(C);
*OutBufCur++ = C;
return *this;
}
raw_ostream &operator<<(const StringRef &Str) {
// Inline fast path, particularly for strings with a known length.
size_t Size = Str.size();
// Make sure we can use the fast path.
if (OutBufCur+Size > OutBufEnd)
return write(Str.data(), Size);
memcpy(OutBufCur, Str.data(), Size);
OutBufCur += Size;
return *this;
}
raw_ostream &operator<<(const char *Str) {
// Inline fast path, particulary for constant strings where a sufficiently
// smart compiler will simplify strlen.
this->operator<<(StringRef(Str));
return *this;
}
raw_ostream &operator<<(const std::string &Str) {
// Avoid the fast path, it would only increase code size for a marginal win.
write(Str.data(), Str.length());
return *this;
}
raw_ostream &operator<<(unsigned long N);
raw_ostream &operator<<(long N);
raw_ostream &operator<<(unsigned long long N);
raw_ostream &operator<<(long long N);
raw_ostream &operator<<(const void *P);
raw_ostream &operator<<(unsigned int N) {
this->operator<<(static_cast<unsigned long>(N));
return *this;
}
raw_ostream &operator<<(int N) {
this->operator<<(static_cast<long>(N));
return *this;
}
raw_ostream &operator<<(double N) {
this->operator<<(ftostr(N));
return *this;
}
/// write_hex - Output \arg N in hexadecimal, without any prefix or padding.
raw_ostream &write_hex(unsigned long long N);
raw_ostream &write(unsigned char C);
raw_ostream &write(const char *Ptr, size_t Size);
// Formatted output, see the format() function in Support/Format.h.
raw_ostream &operator<<(const format_object_base &Fmt);
/// indent - Insert 'NumSpaces' spaces.
raw_ostream &indent(unsigned NumSpaces);
/// Changes the foreground color of text that will be output from this point
/// forward.
/// @param colors ANSI color to use, the special SAVEDCOLOR can be used to
/// change only the bold attribute, and keep colors untouched
/// @param bold bold/brighter text, default false
/// @param bg if true change the background, default: change foreground
/// @returns itself so it can be used within << invocations
virtual raw_ostream &changeColor(enum Colors colors, bool bold=false,
bool bg=false) { return *this; }
/// Resets the colors to terminal defaults. Call this when you are done
/// outputting colored text, or before program exit.
virtual raw_ostream &resetColor() { return *this; }
//===--------------------------------------------------------------------===//
// Subclass Interface
//===--------------------------------------------------------------------===//
private:
/// write_impl - The is the piece of the class that is implemented
/// by subclasses. This writes the \args Size bytes starting at
/// \arg Ptr to the underlying stream.
///
/// This function is guaranteed to only be called at a point at which it is
/// safe for the subclass to install a new buffer via SetBuffer.
///
/// \arg Ptr - The start of the data to be written. For buffered streams this
/// is guaranteed to be the start of the buffer.
/// \arg Size - The number of bytes to be written.
///
/// \invariant { Size > 0 }
virtual void write_impl(const char *Ptr, size_t Size) = 0;
// An out of line virtual method to provide a home for the class vtable.
virtual void handle();
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos() = 0;
protected:
/// SetBuffer - Use the provided buffer as the raw_ostream buffer. This is
/// intended for use only by subclasses which can arrange for the output to go
/// directly into the desired output buffer, instead of being copied on each
/// flush.
void SetBuffer(char *BufferStart, size_t Size) {
SetBufferAndMode(BufferStart, Size, ExternalBuffer);
}
/// preferred_buffer_size - Return an efficient buffer size for the
/// underlying output mechanism.
virtual size_t preferred_buffer_size();
/// error_detected - Set the flag indicating that an output error has
/// been encountered.
void error_detected() { Error = true; }
/// getBufferStart - Return the beginning of the current stream buffer, or 0
/// if the stream is unbuffered.
const char *getBufferStart() const { return OutBufStart; }
//===--------------------------------------------------------------------===//
// Private Interface
//===--------------------------------------------------------------------===//
private:
/// SetBufferAndMode - Install the given buffer and mode.
void SetBufferAndMode(char *BufferStart, size_t Size, BufferKind Mode);
/// flush_nonempty - Flush the current buffer, which is known to be
/// non-empty. This outputs the currently buffered data and resets
/// the buffer to empty.
void flush_nonempty();
/// copy_to_buffer - Copy data into the buffer. Size must not be
/// greater than the number of unused bytes in the buffer.
void copy_to_buffer(const char *Ptr, size_t Size);
};
//===----------------------------------------------------------------------===//
// File Output Streams
//===----------------------------------------------------------------------===//
/// raw_fd_ostream - A raw_ostream that writes to a file descriptor.
///
class raw_fd_ostream : public raw_ostream {
int FD;
bool ShouldClose;
uint64_t pos;
/// write_impl - See raw_ostream::write_impl.
virtual void write_impl(const char *Ptr, size_t Size);
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos() { return pos; }
/// preferred_buffer_size - Determine an efficient buffer size.
virtual size_t preferred_buffer_size();
public:
enum {
/// F_Force - When opening a file, this flag makes raw_fd_ostream overwrite
/// a file if it already exists instead of emitting an error. This may not
/// be specified with F_Append.
F_Force = 1,
/// F_Append - When opening a file, if it already exists append to the
/// existing file instead of returning an error. This may not be specified
/// with F_Force.
F_Append = 2,
/// F_Binary - The file should be opened in binary mode on platforms that
/// support this distinction.
F_Binary = 4
};
/// raw_fd_ostream - Open the specified file for writing. If an error occurs,
/// information about the error is put into ErrorInfo, and the stream should
/// be immediately destroyed; the string will be empty if no error occurred.
/// This allows optional flags to control how the file will be opened.
///
/// \param Filename - The file to open. If this is "-" then the
/// stream will use stdout instead.
raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
unsigned Flags = 0);
/// raw_fd_ostream ctor - FD is the file descriptor that this writes to. If
/// ShouldClose is true, this closes the file when the stream is destroyed.
raw_fd_ostream(int fd, bool shouldClose,
bool unbuffered=false) : raw_ostream(unbuffered), FD(fd),
ShouldClose(shouldClose) {}
~raw_fd_ostream();
/// close - Manually flush the stream and close the file.
void close();
/// seek - Flushes the stream and repositions the underlying file descriptor
/// positition to the offset specified from the beginning of the file.
uint64_t seek(uint64_t off);
virtual raw_ostream &changeColor(enum Colors colors, bool bold=false,
bool bg=false);
virtual raw_ostream &resetColor();
};
/// raw_stdout_ostream - This is a stream that always prints to stdout.
///
class raw_stdout_ostream : public raw_fd_ostream {
// An out of line virtual method to provide a home for the class vtable.
virtual void handle();
public:
raw_stdout_ostream();
};
/// raw_stderr_ostream - This is a stream that always prints to stderr.
///
class raw_stderr_ostream : public raw_fd_ostream {
// An out of line virtual method to provide a home for the class vtable.
virtual void handle();
public:
raw_stderr_ostream();
};
/// outs() - This returns a reference to a raw_ostream for standard output.
/// Use it like: outs() << "foo" << "bar";
raw_ostream &outs();
/// errs() - This returns a reference to a raw_ostream for standard error.
/// Use it like: errs() << "foo" << "bar";
raw_ostream &errs();
/// nulls() - This returns a reference to a raw_ostream which simply discards
/// output.
raw_ostream &nulls();
//===----------------------------------------------------------------------===//
// Output Stream Adaptors
//===----------------------------------------------------------------------===//
/// raw_os_ostream - A raw_ostream that writes to an std::ostream. This is a
/// simple adaptor class. It does not check for output errors; clients should
/// use the underlying stream to detect errors.
class raw_os_ostream : public raw_ostream {
std::ostream &OS;
/// write_impl - See raw_ostream::write_impl.
virtual void write_impl(const char *Ptr, size_t Size);
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos();
public:
raw_os_ostream(std::ostream &O) : OS(O) {}
~raw_os_ostream();
};
/// raw_string_ostream - A raw_ostream that writes to an std::string. This is a
/// simple adaptor class. This class does not encounter output errors.
class raw_string_ostream : public raw_ostream {
std::string &OS;
/// write_impl - See raw_ostream::write_impl.
virtual void write_impl(const char *Ptr, size_t Size);
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos() { return OS.size(); }
public:
explicit raw_string_ostream(std::string &O) : OS(O) {}
~raw_string_ostream();
/// str - Flushes the stream contents to the target string and returns
/// the string's reference.
std::string& str() {
flush();
return OS;
}
};
/// raw_svector_ostream - A raw_ostream that writes to an SmallVector or
/// SmallString. This is a simple adaptor class. This class does not
/// encounter output errors.
class raw_svector_ostream : public raw_ostream {
SmallVectorImpl<char> &OS;
/// write_impl - See raw_ostream::write_impl.
virtual void write_impl(const char *Ptr, size_t Size);
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos();
public:
/// Construct a new raw_svector_ostream.
///
/// \arg O - The vector to write to; this should generally have at least 128
/// bytes free to avoid any extraneous memory overhead.
explicit raw_svector_ostream(SmallVectorImpl<char> &O);
~raw_svector_ostream();
/// str - Flushes the stream contents to the target vector and return a
/// StringRef for the vector contents.
StringRef str();
};
/// raw_null_ostream - A raw_ostream that discards all output.
class raw_null_ostream : public raw_ostream {
/// write_impl - See raw_ostream::write_impl.
virtual void write_impl(const char *Ptr, size_t size);
/// current_pos - Return the current position within the stream, not
/// counting the bytes currently in the buffer.
virtual uint64_t current_pos();
public:
explicit raw_null_ostream() {}
~raw_null_ostream();
};
} // end llvm namespace
#endif