X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FSupport%2Fraw_ostream.h;h=34fbe082cda804178647039e0d00b9c30f6bd048;hb=c92330c18ce2f7015f0db88e4bfce3d253fa3c57;hp=8242f04e23ce4670fa2e3d8005b3c8c284adeff5;hpb=62fe47a33755719ab9c6e8c239e0dd01fc87e6f9;p=oota-llvm.git diff --git a/include/llvm/Support/raw_ostream.h b/include/llvm/Support/raw_ostream.h index 8242f04e23c..34fbe082cda 100644 --- a/include/llvm/Support/raw_ostream.h +++ b/include/llvm/Support/raw_ostream.h @@ -14,35 +14,55 @@ #ifndef LLVM_SUPPORT_RAW_OSTREAM_H #define LLVM_SUPPORT_RAW_OSTREAM_H -#include "llvm/ADT/StringExtras.h" -#include -#include -#include -#include +#include "llvm/ADT/StringRef.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/DataTypes.h" namespace llvm { class format_object_base; template 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 { 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 (Unbuffered == true) - /// 1. Uninitialized (Unbuffered == false && OutBufStart == 0). - /// 2. Buffered (Unbuffered == false && OutBufStart != 0 && - /// OutBufEnd - OutBufStart >= 64). + /// 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: // color order matches ANSI escape sequence, don't change @@ -58,49 +78,52 @@ public: SAVEDCOLOR }; - explicit raw_ostream(bool unbuffered=false) : Unbuffered(unbuffered) { + 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() { return current_pos() + GetNumBytesInBuffer(); } + 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=4096) { - 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; - Unbuffered = false; + 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() { flush(); - - delete [] OutBufStart; - OutBufStart = OutBufEnd = OutBufCur = 0; - Unbuffered = true; + SetBufferAndMode(nullptr, 0, Unbuffered); } - unsigned GetNumBytesInBuffer() const { + size_t GetNumBytesInBuffer() const { return OutBufCur - OutBufStart; } @@ -134,24 +157,29 @@ public: return *this; } - raw_ostream &operator<<(const char *Str) { - // Inline fast path, particulary for constant strings where a - // sufficiently smart compiler will simplify strlen. - - unsigned Size = strlen(Str); + 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 (OutBufCur+Size > OutBufEnd) - return write(Str, Size); + if (Size > (size_t)(OutBufEnd - OutBufCur)) + return write(Str.data(), Size); - memcpy(OutBufCur, Str, Size); + memcpy(OutBufCur, Str.data(), Size); OutBufCur += Size; return *this; } - raw_ostream &operator<<(const std::string& Str) { - write(Str.data(), Str.length()); - return *this; + raw_ostream &operator<<(const char *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) { + // Avoid the fast path, it would only increase code size for a marginal win. + return write(Str.data(), Str.length()); } raw_ostream &operator<<(unsigned long N); @@ -160,67 +188,122 @@ public: raw_ostream &operator<<(long long N); raw_ostream &operator<<(const void *P); raw_ostream &operator<<(unsigned int N) { - this->operator<<(static_cast(N)); - return *this; + return this->operator<<(static_cast(N)); } raw_ostream &operator<<(int N) { - this->operator<<(static_cast(N)); - return *this; + return this->operator<<(static_cast(N)); } - raw_ostream &operator<<(double N) { - this->operator<<(ftostr(N)); - return *this; - } + 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(unsigned char C); - raw_ostream &write(const char *Ptr, unsigned Size); + 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 + /// @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 + /// @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; } + 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 //===--------------------------------------------------------------------===// 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. - /// + /// 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, unsigned 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; + 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); }; //===----------------------------------------------------------------------===// @@ -232,66 +315,99 @@ private: 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. - virtual void write_impl(const char *Ptr, unsigned Size); + 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. - virtual uint64_t current_pos() { return pos; } + 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(int fd, bool shouldClose, bool unbuffered=false); + ~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 + GetNumBytesInBuffer(); } - /// 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); - virtual raw_ostream &changeColor(enum Colors colors, bool bold=false, - bool bg=false); - virtual raw_ostream &resetColor(); -}; + /// 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_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_ostream &changeColor(enum Colors colors, bool bold=false, + bool bg=false) override; + raw_ostream &resetColor() override; -/// 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 &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. @@ -302,49 +418,29 @@ raw_ostream &outs(); /// 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; - - /// write_impl - See raw_ostream::write_impl. - virtual void write_impl(const char *Ptr, unsigned 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(); - - /// tell - Return the current offset with the stream. - uint64_t tell(); -}; - /// 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. - virtual void write_impl(const char *Ptr, unsigned Size); + 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. - virtual uint64_t current_pos() { return OS.size(); } + 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(); - /// tell - Return the current offset with the stream. - uint64_t tell() { return OS.size() + GetNumBytesInBuffer(); } - /// str - Flushes the stream contents to the target string and returns /// the string's reference. std::string& str() { @@ -354,22 +450,47 @@ public: }; /// 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 &OS; /// write_impl - See raw_ostream::write_impl. - virtual void write_impl(const char *Ptr, unsigned Size); + 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. - virtual uint64_t current_pos(); + uint64_t current_pos() const override; public: - raw_svector_ostream(SmallVectorImpl &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 &O); ~raw_svector_ostream(); - /// tell - Return the current offset with the stream. - uint64_t tell(); + /// 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