#ifndef LLVM_SUPPORT_RAW_OSTREAM_H
#define LLVM_SUPPORT_RAW_OSTREAM_H
-#include "llvm/ADT/StringExtras.h"
-#include <cassert>
-#include <cstring>
-#include <string>
-#include <iosfwd>
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/DataTypes.h"
namespace llvm {
class format_object_base;
template <typename T>
class SmallVectorImpl;
+ namespace sys {
+ namespace fs {
+ enum OpenFlags : unsigned;
+ }
+ }
+
/// 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 {
-protected:
+private:
+ void operator=(const raw_ostream &) LLVM_DELETED_FUNCTION;
+ raw_ostream(const raw_ostream &) LLVM_DELETED_FUNCTION;
+
+ /// 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 >= 1).
+ ///
+ /// 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;
- bool Unbuffered;
+
+ enum BufferKind {
+ Unbuffered = 0,
+ InternalBuffer,
+ ExternalBuffer
+ } BufferMode;
public:
- explicit raw_ostream(bool unbuffered=false) : Unbuffered(unbuffered) {
+ // 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) {
// Start out ready to flush.
- OutBufStart = OutBufEnd = OutBufCur = 0;
+ OutBufStart = OutBufEnd = OutBufCur = nullptr;
}
- virtual ~raw_ostream() {
- delete [] OutBufStart;
- }
+ virtual ~raw_ostream();
+
+ /// tell - Return the current offset with the file.
+ uint64_t tell() const { return current_pos() + GetNumBytesInBuffer(); }
//===--------------------------------------------------------------------===//
// Configuration Interface
//===--------------------------------------------------------------------===//
- /// SetBufferSize - Set the internal buffer size to the specified amount
- /// instead of the default.
- void SetBufferSize(unsigned Size) {
- assert(Size >= 64 &&
- "Buffer size must be somewhat large for invariants to hold");
+ /// 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);
+ }
- delete [] OutBufStart;
- OutBufStart = new char[Size];
- OutBufEnd = OutBufStart+Size;
- OutBufCur = OutBufStart;
+ size_t GetBufferSize() const {
+ // 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 == nullptr)
+ return preferred_buffer_size();
+
+ // Otherwise just return the size of the allocated buffer.
+ return OutBufEnd - OutBufStart;
}
- /// SetUnbuffered - Set the streams buffering status. When
- /// unbuffered the stream will flush after every write. This routine
+ /// 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(bool unbuffered) {
- Unbuffered = unbuffered;
- if (Unbuffered)
- flush();
+ void SetUnbuffered() {
+ flush();
+ SetBufferAndMode(nullptr, 0, Unbuffered);
+ }
+
+ size_t GetNumBytesInBuffer() const {
+ return OutBufCur - OutBufStart;
}
//===--------------------------------------------------------------------===//
void flush() {
if (OutBufCur != OutBufStart)
- flush_impl();
+ flush_nonempty();
}
raw_ostream &operator<<(char C) {
if (OutBufCur >= OutBufEnd)
- flush_impl();
+ return write(C);
*OutBufCur++ = C;
return *this;
}
raw_ostream &operator<<(unsigned char C) {
if (OutBufCur >= OutBufEnd)
- flush_impl();
+ return write(C);
*OutBufCur++ = C;
return *this;
}
raw_ostream &operator<<(signed char C) {
if (OutBufCur >= OutBufEnd)
- flush_impl();
+ return write(C);
*OutBufCur++ = C;
return *this;
}
+ raw_ostream &operator<<(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 (Size > (size_t)(OutBufEnd - OutBufCur))
+ return write(Str.data(), Size);
+
+ memcpy(OutBufCur, Str.data(), Size);
+ OutBufCur += Size;
+ return *this;
+ }
+
raw_ostream &operator<<(const char *Str) {
- return write(Str, strlen(Str));
+ // Inline fast path, particularly for constant strings where a sufficiently
+ // smart compiler will simplify strlen.
+
+ return this->operator<<(StringRef(Str));
}
- raw_ostream &operator<<(const std::string& Str) {
+ raw_ostream &operator<<(const std::string &Str) {
+ // Avoid the fast path, it would only increase code size for a marginal win.
return write(Str.data(), Str.length());
}
return this->operator<<(static_cast<long>(N));
}
- raw_ostream &operator<<(double N) {
- return this->operator<<(ftostr(N));
- }
+ raw_ostream &operator<<(double N);
+
+ /// write_hex - Output \p N in hexadecimal, without any prefix or padding.
+ raw_ostream &write_hex(unsigned long long N);
+
+ /// write_escaped - Output \p Str, turning '\\', '\t', '\n', '"', and
+ /// anything that doesn't satisfy std::isprint into an escape sequence.
+ raw_ostream &write_escaped(StringRef Str, bool UseHexEscapes = false);
- raw_ostream &write(const char *Ptr, unsigned Size);
+ 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 Color 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 Color,
+ bool Bold = false,
+ bool BG = false) {
+ (void)Color;
+ (void)Bold;
+ (void)BG;
+ 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; }
+
+ /// Reverses the forground and background colors.
+ virtual raw_ostream &reverseColor() { return *this; }
+
+ /// This function determines if this stream is connected to a "tty" or
+ /// "console" window. That is, the output would be displayed to the user
+ /// rather than being put on a pipe or stored in a file.
+ virtual bool is_displayed() const { return false; }
+
+ /// This function determines if this stream is displayed and supports colors.
+ virtual bool has_colors() const { return is_displayed(); }
+
//===--------------------------------------------------------------------===//
// Subclass Interface
//===--------------------------------------------------------------------===//
-protected:
-
- /// flush_impl - The is the piece of the class that is implemented by
- /// subclasses. This outputs the currently buffered data and resets the
- /// buffer to empty.
- virtual void flush_impl() = 0;
-
- /// HandleFlush - A stream's implementation of flush should call this after
- /// emitting the bytes to the data sink.
- void HandleFlush() {
- if (OutBufStart == 0)
- SetBufferSize(4096);
- OutBufCur = OutBufStart;
- }
private:
+ /// write_impl - The is the piece of the class that is implemented
+ /// by subclasses. This writes the \p Size bytes starting at
+ /// \p 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.
+ ///
+ /// \param Ptr The start of the data to be written. For buffered streams this
+ /// is guaranteed to be the start of the buffer.
+ ///
+ /// \param 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() const = 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() const;
+
+ /// 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);
};
//===----------------------------------------------------------------------===//
class raw_fd_ostream : public raw_ostream {
int FD;
bool ShouldClose;
+
+ /// Error This flag is true if an error of any kind has been detected.
+ ///
+ bool Error;
+
+ /// Controls whether the stream should attempt to use atomic writes, when
+ /// possible.
+ bool UseAtomicWrites;
+
uint64_t pos;
+
+ /// write_impl - See raw_ostream::write_impl.
+ void write_impl(const char *Ptr, size_t Size) override;
+
+ /// current_pos - Return the current position within the stream, not
+ /// counting the bytes currently in the buffer.
+ uint64_t current_pos() const override { return pos; }
+
+ /// preferred_buffer_size - Determine an efficient buffer size.
+ size_t preferred_buffer_size() const override;
+
+ /// error_detected - Set the flag indicating that an output error has
+ /// been encountered.
+ void error_detected() { Error = true; }
+
public:
- /// 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.
+ /// 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.
- /// \param Binary - The file should be opened in binary mode on
- /// platforms that support this distinction.
- raw_fd_ostream(const char *Filename, bool Binary, std::string &ErrorInfo);
+ /// As a special case, if Filename is "-", then the stream will use
+ /// STDOUT_FILENO instead of opening a file. Note that it will still consider
+ /// itself to own the file descriptor. In particular, it will close the
+ /// file descriptor when it is done (this is necessary to detect
+ /// output errors).
+ raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
+ sys::fs::OpenFlags Flags);
/// 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();
+ raw_fd_ostream(int fd, bool shouldClose, bool unbuffered=false);
- /// flush_impl - The is the piece of the class that is implemented by
- /// subclasses. This outputs the currently buffered data and resets the
- /// buffer to empty.
- virtual void flush_impl();
+ ~raw_fd_ostream();
/// close - Manually flush the stream and close the file.
+ /// Note that this does not call fsync.
void close();
- /// tell - Return the current offset with the file.
- uint64_t tell() {
- return pos + (OutBufCur - OutBufStart);
- }
-
/// seek - Flushes the stream and repositions the underlying file descriptor
- /// positition to the offset specified from the beginning of the file.
+ /// position to the offset specified from the beginning of the file.
uint64_t seek(uint64_t off);
-};
-/// 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();
-};
+ /// SetUseAtomicWrite - Set the stream to attempt to use atomic writes for
+ /// individual output routines where possible.
+ ///
+ /// Note that because raw_ostream's are typically buffered, this flag is only
+ /// sensible when used on unbuffered streams which will flush their output
+ /// immediately.
+ void SetUseAtomicWrites(bool Value) {
+ UseAtomicWrites = Value;
+ }
-/// 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();
+ raw_ostream &changeColor(enum Colors colors, bool bold=false,
+ bool bg=false) override;
+ raw_ostream &resetColor() override;
+
+ raw_ostream &reverseColor() override;
+
+ bool is_displayed() const override;
+
+ bool has_colors() const override;
+
+ /// has_error - Return the value of the flag in this raw_fd_ostream indicating
+ /// whether an output error has been encountered.
+ /// This doesn't implicitly flush any pending output. Also, it doesn't
+ /// guarantee to detect all errors unless the stream has been closed.
+ 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,
+ /// report_fatal_error is called to report the error. Use clear_error()
+ /// after handling the error to avoid this behavior.
+ ///
+ /// "Errors should never pass silently.
+ /// Unless explicitly silenced."
+ /// - from The Zen of Python, by Tim Peters
+ ///
+ void clear_error() {
+ Error = false;
+ }
};
/// outs() - This returns a reference to a raw_ostream for standard output.
/// 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.
-class raw_os_ostream : public raw_ostream {
- std::ostream &OS;
-public:
- raw_os_ostream(std::ostream &O) : OS(O) {}
- ~raw_os_ostream();
-
- /// flush_impl - The is the piece of the class that is implemented by
- /// subclasses. This outputs the currently buffered data and resets the
- /// buffer to empty.
- virtual void flush_impl();
-};
-
/// raw_string_ostream - A raw_ostream that writes to an std::string. This is a
-/// simple adaptor class.
+/// 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.
+ void write_impl(const char *Ptr, size_t Size) override;
+
+ /// current_pos - Return the current position within the stream, not
+ /// counting the bytes currently in the buffer.
+ uint64_t current_pos() const override { return OS.size(); }
public:
- raw_string_ostream(std::string &O) : OS(O) {}
+ explicit raw_string_ostream(std::string &O) : OS(O) {}
~raw_string_ostream();
/// str - Flushes the stream contents to the target string and returns
flush();
return OS;
}
-
- /// flush_impl - The is the piece of the class that is implemented by
- /// subclasses. This outputs the currently buffered data and resets the
- /// buffer to empty.
- virtual void flush_impl();
};
/// raw_svector_ostream - A raw_ostream that writes to an SmallVector or
-/// SmallString. This is a simple adaptor class.
+/// 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.
+ void write_impl(const char *Ptr, size_t Size) override;
+
+ /// current_pos - Return the current position within the stream, not
+ /// counting the bytes currently in the buffer.
+ uint64_t current_pos() const override;
public:
- raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {}
+ /// Construct a new raw_svector_ostream.
+ ///
+ /// \param 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();
- /// flush_impl - The is the piece of the class that is implemented by
- /// subclasses. This outputs the currently buffered data and resets the
- /// buffer to empty.
- virtual void flush_impl();
+ /// resync - This is called when the SmallVector we're appending to is changed
+ /// outside of the raw_svector_ostream's control. It is only safe to do this
+ /// if the raw_svector_ostream has previously been flushed.
+ void resync();
+
+ /// 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.
+ void write_impl(const char *Ptr, size_t size) override;
+
+ /// current_pos - Return the current position within the stream, not
+ /// counting the bytes currently in the buffer.
+ uint64_t current_pos() const override;
+
+public:
+ explicit raw_null_ostream() {}
+ ~raw_null_ostream();
};
} // end llvm namespace