//===--- raw_ostream.cpp - Implement the raw_ostream classes --------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This implements support for bulk buffered stream output. // //===----------------------------------------------------------------------===// #include "llvm/Support/raw_ostream.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/StringExtras.h" #include "llvm/Config/config.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/Format.h" #include "llvm/Support/MathExtras.h" #include "llvm/Support/Process.h" #include "llvm/Support/Program.h" #include <cctype> #include <cerrno> #include <sys/stat.h> #include <system_error> // <fcntl.h> may provide O_BINARY. #if defined(HAVE_FCNTL_H) # include <fcntl.h> #endif #if defined(HAVE_UNISTD_H) # include <unistd.h> #endif #if defined(HAVE_SYS_UIO_H) && defined(HAVE_WRITEV) # include <sys/uio.h> #endif #if defined(__CYGWIN__) #include <io.h> #endif #if defined(_MSC_VER) #include <io.h> #ifndef STDIN_FILENO # define STDIN_FILENO 0 #endif #ifndef STDOUT_FILENO # define STDOUT_FILENO 1 #endif #ifndef STDERR_FILENO # define STDERR_FILENO 2 #endif #endif #ifdef LLVM_ON_WIN32 #include "Windows/WindowsSupport.h" #endif using namespace llvm; raw_ostream::~raw_ostream() { // raw_ostream's subclasses should take care to flush the buffer // in their destructors. assert(OutBufCur == OutBufStart && "raw_ostream destructor called with non-empty buffer!"); if (BufferMode == InternalBuffer) delete [] OutBufStart; } // An out of line virtual method to provide a home for the class vtable. void raw_ostream::handle() {} size_t raw_ostream::preferred_buffer_size() const { // BUFSIZ is intended to be a reasonable default. return BUFSIZ; } void raw_ostream::SetBuffered() { // Ask the subclass to determine an appropriate buffer size. if (size_t Size = preferred_buffer_size()) SetBufferSize(Size); else // It may return 0, meaning this stream should be unbuffered. SetUnbuffered(); } void raw_ostream::SetBufferAndMode(char *BufferStart, size_t Size, BufferKind Mode) { assert(((Mode == Unbuffered && !BufferStart && Size == 0) || (Mode != Unbuffered && BufferStart && Size != 0)) && "stream must be unbuffered or have at least one byte"); // Make sure the current buffer is free of content (we can't flush here; the // child buffer management logic will be in write_impl). assert(GetNumBytesInBuffer() == 0 && "Current buffer is non-empty!"); if (BufferMode == InternalBuffer) delete [] OutBufStart; OutBufStart = BufferStart; OutBufEnd = OutBufStart+Size; OutBufCur = OutBufStart; BufferMode = Mode; assert(OutBufStart <= OutBufEnd && "Invalid size!"); } raw_ostream &raw_ostream::operator<<(unsigned long N) { // Zero is a special case. if (N == 0) return *this << '0'; char NumberBuffer[20]; char *EndPtr = NumberBuffer+sizeof(NumberBuffer); char *CurPtr = EndPtr; while (N) { *--CurPtr = '0' + char(N % 10); N /= 10; } return write(CurPtr, EndPtr-CurPtr); } raw_ostream &raw_ostream::operator<<(long N) { if (N < 0) { *this << '-'; // Avoid undefined behavior on LONG_MIN with a cast. N = -(unsigned long)N; } return this->operator<<(static_cast<unsigned long>(N)); } raw_ostream &raw_ostream::operator<<(unsigned long long N) { // Output using 32-bit div/mod when possible. if (N == static_cast<unsigned long>(N)) return this->operator<<(static_cast<unsigned long>(N)); char NumberBuffer[20]; char *EndPtr = std::end(NumberBuffer); char *CurPtr = EndPtr; while (N) { *--CurPtr = '0' + char(N % 10); N /= 10; } return write(CurPtr, EndPtr-CurPtr); } raw_ostream &raw_ostream::operator<<(long long N) { if (N < 0) { *this << '-'; // Avoid undefined behavior on INT64_MIN with a cast. N = -(unsigned long long)N; } return this->operator<<(static_cast<unsigned long long>(N)); } raw_ostream &raw_ostream::write_hex(unsigned long long N) { // Zero is a special case. if (N == 0) return *this << '0'; char NumberBuffer[16]; char *EndPtr = std::end(NumberBuffer); char *CurPtr = EndPtr; while (N) { unsigned char x = static_cast<unsigned char>(N) % 16; *--CurPtr = hexdigit(x, /*LowerCase*/true); N /= 16; } return write(CurPtr, EndPtr-CurPtr); } raw_ostream &raw_ostream::write_escaped(StringRef Str, bool UseHexEscapes) { for (unsigned char c : Str) { switch (c) { case '\\': *this << '\\' << '\\'; break; case '\t': *this << '\\' << 't'; break; case '\n': *this << '\\' << 'n'; break; case '"': *this << '\\' << '"'; break; default: if (std::isprint(c)) { *this << c; break; } // Write out the escaped representation. if (UseHexEscapes) { *this << '\\' << 'x'; *this << hexdigit((c >> 4 & 0xF)); *this << hexdigit((c >> 0) & 0xF); } else { // Always use a full 3-character octal escape. *this << '\\'; *this << char('0' + ((c >> 6) & 7)); *this << char('0' + ((c >> 3) & 7)); *this << char('0' + ((c >> 0) & 7)); } } } return *this; } raw_ostream &raw_ostream::operator<<(const void *P) { *this << '0' << 'x'; return write_hex((uintptr_t) P); } raw_ostream &raw_ostream::operator<<(double N) { #ifdef _WIN32 // On MSVCRT and compatible, output of %e is incompatible to Posix // by default. Number of exponent digits should be at least 2. "%+03d" // FIXME: Implement our formatter to here or Support/Format.h! #if defined(__MINGW32__) // FIXME: It should be generic to C++11. if (N == 0.0 && std::signbit(N)) return *this << "-0.000000e+00"; #else int fpcl = _fpclass(N); // negative zero if (fpcl == _FPCLASS_NZ) return *this << "-0.000000e+00"; #endif char buf[16]; unsigned len; len = format("%e", N).snprint(buf, sizeof(buf)); if (len <= sizeof(buf) - 2) { if (len >= 5 && buf[len - 5] == 'e' && buf[len - 3] == '0') { int cs = buf[len - 4]; if (cs == '+' || cs == '-') { int c1 = buf[len - 2]; int c0 = buf[len - 1]; if (isdigit(static_cast<unsigned char>(c1)) && isdigit(static_cast<unsigned char>(c0))) { // Trim leading '0': "...e+012" -> "...e+12\0" buf[len - 3] = c1; buf[len - 2] = c0; buf[--len] = 0; } } } return this->operator<<(buf); } #endif return this->operator<<(format("%e", N)); } void raw_ostream::flush_nonempty() { assert(OutBufCur > OutBufStart && "Invalid call to flush_nonempty."); size_t Length = OutBufCur - OutBufStart; OutBufCur = OutBufStart; write_impl(OutBufStart, Length); } raw_ostream &raw_ostream::write(unsigned char C) { // Group exceptional cases into a single branch. if (LLVM_UNLIKELY(OutBufCur >= OutBufEnd)) { if (LLVM_UNLIKELY(!OutBufStart)) { if (BufferMode == Unbuffered) { write_impl(reinterpret_cast<char*>(&C), 1); return *this; } // Set up a buffer and start over. SetBuffered(); return write(C); } flush_nonempty(); } *OutBufCur++ = C; return *this; } raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) { // Group exceptional cases into a single branch. if (LLVM_UNLIKELY(size_t(OutBufEnd - OutBufCur) < Size)) { if (LLVM_UNLIKELY(!OutBufStart)) { if (BufferMode == Unbuffered) { write_impl(Ptr, Size); return *this; } // Set up a buffer and start over. SetBuffered(); return write(Ptr, Size); } size_t NumBytes = OutBufEnd - OutBufCur; // If the buffer is empty at this point we have a string that is larger // than the buffer. Directly write the chunk that is a multiple of the // preferred buffer size and put the remainder in the buffer. if (LLVM_UNLIKELY(OutBufCur == OutBufStart)) { assert(NumBytes != 0 && "undefined behavior"); size_t BytesToWrite = Size - (Size % NumBytes); write_impl(Ptr, BytesToWrite); size_t BytesRemaining = Size - BytesToWrite; if (BytesRemaining > size_t(OutBufEnd - OutBufCur)) { // Too much left over to copy into our buffer. return write(Ptr + BytesToWrite, BytesRemaining); } copy_to_buffer(Ptr + BytesToWrite, BytesRemaining); return *this; } // We don't have enough space in the buffer to fit the string in. Insert as // much as possible, flush and start over with the remainder. copy_to_buffer(Ptr, NumBytes); flush_nonempty(); return write(Ptr + NumBytes, Size - NumBytes); } copy_to_buffer(Ptr, Size); return *this; } void raw_ostream::copy_to_buffer(const char *Ptr, size_t Size) { assert(Size <= size_t(OutBufEnd - OutBufCur) && "Buffer overrun!"); // Handle short strings specially, memcpy isn't very good at very short // strings. switch (Size) { case 4: OutBufCur[3] = Ptr[3]; // FALL THROUGH case 3: OutBufCur[2] = Ptr[2]; // FALL THROUGH case 2: OutBufCur[1] = Ptr[1]; // FALL THROUGH case 1: OutBufCur[0] = Ptr[0]; // FALL THROUGH case 0: break; default: memcpy(OutBufCur, Ptr, Size); break; } OutBufCur += Size; } // Formatted output. raw_ostream &raw_ostream::operator<<(const format_object_base &Fmt) { // If we have more than a few bytes left in our output buffer, try // formatting directly onto its end. size_t NextBufferSize = 127; size_t BufferBytesLeft = OutBufEnd - OutBufCur; if (BufferBytesLeft > 3) { size_t BytesUsed = Fmt.print(OutBufCur, BufferBytesLeft); // Common case is that we have plenty of space. if (BytesUsed <= BufferBytesLeft) { OutBufCur += BytesUsed; return *this; } // Otherwise, we overflowed and the return value tells us the size to try // again with. NextBufferSize = BytesUsed; } // If we got here, we didn't have enough space in the output buffer for the // string. Try printing into a SmallVector that is resized to have enough // space. Iterate until we win. SmallVector<char, 128> V; while (1) { V.resize(NextBufferSize); // Try formatting into the SmallVector. size_t BytesUsed = Fmt.print(V.data(), NextBufferSize); // If BytesUsed fit into the vector, we win. if (BytesUsed <= NextBufferSize) return write(V.data(), BytesUsed); // Otherwise, try again with a new size. assert(BytesUsed > NextBufferSize && "Didn't grow buffer!?"); NextBufferSize = BytesUsed; } } raw_ostream &raw_ostream::operator<<(const FormattedString &FS) { unsigned Len = FS.Str.size(); int PadAmount = FS.Width - Len; if (FS.RightJustify && (PadAmount > 0)) this->indent(PadAmount); this->operator<<(FS.Str); if (!FS.RightJustify && (PadAmount > 0)) this->indent(PadAmount); return *this; } raw_ostream &raw_ostream::operator<<(const FormattedNumber &FN) { if (FN.Hex) { unsigned Nibbles = (64 - countLeadingZeros(FN.HexValue)+3)/4; unsigned PrefixChars = FN.HexPrefix ? 2 : 0; unsigned Width = std::max(FN.Width, Nibbles + PrefixChars); char NumberBuffer[20] = "0x0000000000000000"; if (!FN.HexPrefix) NumberBuffer[1] = '0'; char *EndPtr = NumberBuffer+Width; char *CurPtr = EndPtr; unsigned long long N = FN.HexValue; while (N) { unsigned char x = static_cast<unsigned char>(N) % 16; *--CurPtr = hexdigit(x, !FN.Upper); N /= 16; } return write(NumberBuffer, Width); } else { // Zero is a special case. if (FN.DecValue == 0) { this->indent(FN.Width-1); return *this << '0'; } char NumberBuffer[32]; char *EndPtr = NumberBuffer+sizeof(NumberBuffer); char *CurPtr = EndPtr; bool Neg = (FN.DecValue < 0); uint64_t N = Neg ? -static_cast<uint64_t>(FN.DecValue) : FN.DecValue; while (N) { *--CurPtr = '0' + char(N % 10); N /= 10; } int Len = EndPtr - CurPtr; int Pad = FN.Width - Len; if (Neg) --Pad; if (Pad > 0) this->indent(Pad); if (Neg) *this << '-'; return write(CurPtr, Len); } } /// indent - Insert 'NumSpaces' spaces. raw_ostream &raw_ostream::indent(unsigned NumSpaces) { static const char Spaces[] = " " " " " "; // Usually the indentation is small, handle it with a fastpath. if (NumSpaces < array_lengthof(Spaces)) return write(Spaces, NumSpaces); while (NumSpaces) { unsigned NumToWrite = std::min(NumSpaces, (unsigned)array_lengthof(Spaces)-1); write(Spaces, NumToWrite); NumSpaces -= NumToWrite; } return *this; } //===----------------------------------------------------------------------===// // Formatted Output //===----------------------------------------------------------------------===// // Out of line virtual method. void format_object_base::home() { } //===----------------------------------------------------------------------===// // raw_fd_ostream //===----------------------------------------------------------------------===// static int getFD(StringRef Filename, std::error_code &EC, sys::fs::OpenFlags Flags) { // Handle "-" as stdout. Note that when we do this, we consider ourself // the owner of stdout. This means that we can do things like close the // file descriptor when we're done and set the "binary" flag globally. if (Filename == "-") { EC = std::error_code(); // If user requested binary then put stdout into binary mode if // possible. if (!(Flags & sys::fs::F_Text)) sys::ChangeStdoutToBinary(); return STDOUT_FILENO; } int FD; EC = sys::fs::openFileForWrite(Filename, FD, Flags); if (EC) return -1; return FD; } raw_fd_ostream::raw_fd_ostream(StringRef Filename, std::error_code &EC, sys::fs::OpenFlags Flags) : raw_fd_ostream(getFD(Filename, EC, Flags), true) {} /// 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::raw_fd_ostream(int fd, bool shouldClose, bool unbuffered) : raw_pwrite_stream(unbuffered), FD(fd), ShouldClose(shouldClose), Error(false) { if (FD < 0 ) { ShouldClose = false; return; } // Get the starting position. off_t loc = ::lseek(FD, 0, SEEK_CUR); #ifdef LLVM_ON_WIN32 // MSVCRT's _lseek(SEEK_CUR) doesn't return -1 for pipes. sys::fs::file_status Status; std::error_code EC = status(FD, Status); SupportsSeeking = !EC && Status.type() == sys::fs::file_type::regular_file; #else SupportsSeeking = loc != (off_t)-1; #endif if (!SupportsSeeking) pos = 0; else pos = static_cast<uint64_t>(loc); } raw_fd_ostream::~raw_fd_ostream() { if (FD >= 0) { flush(); if (ShouldClose && sys::Process::SafelyCloseFileDescriptor(FD)) error_detected(); } #ifdef __MINGW32__ // On mingw, global dtors should not call exit(). // report_fatal_error() invokes exit(). We know report_fatal_error() // might not write messages to stderr when any errors were detected // on FD == 2. if (FD == 2) return; #endif // If there are any pending errors, report them now. Clients wishing // to avoid report_fatal_error calls should check for errors with // has_error() and clear the error flag with clear_error() before // destructing raw_ostream objects which may have errors. if (has_error()) report_fatal_error("IO failure on output stream.", /*GenCrashDiag=*/false); } void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) { assert(FD >= 0 && "File already closed."); pos += Size; #ifndef LLVM_ON_WIN32 bool ShouldWriteInChunks = false; #else // Writing a large size of output to Windows console returns ENOMEM. It seems // that, prior to Windows 8, WriteFile() is redirecting to WriteConsole(), and // the latter has a size limit (66000 bytes or less, depending on heap usage). bool ShouldWriteInChunks = !!::_isatty(FD) && !RunningWindows8OrGreater(); #endif do { size_t ChunkSize = Size; if (ChunkSize > 32767 && ShouldWriteInChunks) ChunkSize = 32767; ssize_t ret = ::write(FD, Ptr, ChunkSize); if (ret < 0) { // If it's a recoverable error, swallow it and retry the write. // // Ideally we wouldn't ever see EAGAIN or EWOULDBLOCK here, since // raw_ostream isn't designed to do non-blocking I/O. However, some // programs, such as old versions of bjam, have mistakenly used // O_NONBLOCK. For compatibility, emulate blocking semantics by // spinning until the write succeeds. If you don't want spinning, // don't use O_NONBLOCK file descriptors with raw_ostream. if (errno == EINTR || errno == EAGAIN #ifdef EWOULDBLOCK || errno == EWOULDBLOCK #endif ) continue; // Otherwise it's a non-recoverable error. Note it and quit. error_detected(); break; } // The write may have written some or all of the data. Update the // size and buffer pointer to reflect the remainder that needs // to be written. If there are no bytes left, we're done. Ptr += ret; Size -= ret; } while (Size > 0); } void raw_fd_ostream::close() { assert(ShouldClose); ShouldClose = false; flush(); if (sys::Process::SafelyCloseFileDescriptor(FD)) error_detected(); FD = -1; } uint64_t raw_fd_ostream::seek(uint64_t off) { assert(SupportsSeeking && "Stream does not support seeking!"); flush(); pos = ::lseek(FD, off, SEEK_SET); if (pos == (uint64_t)-1) error_detected(); return pos; } void raw_fd_ostream::pwrite_impl(const char *Ptr, size_t Size, uint64_t Offset) { uint64_t Pos = tell(); seek(Offset); write(Ptr, Size); seek(Pos); } size_t raw_fd_ostream::preferred_buffer_size() const { #if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(__minix) // Windows and Minix have no st_blksize. assert(FD >= 0 && "File not yet open!"); struct stat statbuf; if (fstat(FD, &statbuf) != 0) return 0; // If this is a terminal, don't use buffering. Line buffering // would be a more traditional thing to do, but it's not worth // the complexity. if (S_ISCHR(statbuf.st_mode) && isatty(FD)) return 0; // Return the preferred block size. return statbuf.st_blksize; #else return raw_ostream::preferred_buffer_size(); #endif } raw_ostream &raw_fd_ostream::changeColor(enum Colors colors, bool bold, bool bg) { if (sys::Process::ColorNeedsFlush()) flush(); const char *colorcode = (colors == SAVEDCOLOR) ? sys::Process::OutputBold(bg) : sys::Process::OutputColor(colors, bold, bg); if (colorcode) { size_t len = strlen(colorcode); write(colorcode, len); // don't account colors towards output characters pos -= len; } return *this; } raw_ostream &raw_fd_ostream::resetColor() { if (sys::Process::ColorNeedsFlush()) flush(); const char *colorcode = sys::Process::ResetColor(); if (colorcode) { size_t len = strlen(colorcode); write(colorcode, len); // don't account colors towards output characters pos -= len; } return *this; } raw_ostream &raw_fd_ostream::reverseColor() { if (sys::Process::ColorNeedsFlush()) flush(); const char *colorcode = sys::Process::OutputReverse(); if (colorcode) { size_t len = strlen(colorcode); write(colorcode, len); // don't account colors towards output characters pos -= len; } return *this; } bool raw_fd_ostream::is_displayed() const { return sys::Process::FileDescriptorIsDisplayed(FD); } bool raw_fd_ostream::has_colors() const { return sys::Process::FileDescriptorHasColors(FD); } //===----------------------------------------------------------------------===// // outs(), errs(), nulls() //===----------------------------------------------------------------------===// /// outs() - This returns a reference to a raw_ostream for standard output. /// Use it like: outs() << "foo" << "bar"; raw_ostream &llvm::outs() { // Set buffer settings to model stdout behavior. Delete the file descriptor // when the program exits, forcing error detection. This means that if you // ever call outs(), you can't open another raw_fd_ostream on stdout, as we'll // close stdout twice and print an error the second time. std::error_code EC; static raw_fd_ostream S("-", EC, sys::fs::F_None); assert(!EC); return S; } /// errs() - This returns a reference to a raw_ostream for standard error. /// Use it like: errs() << "foo" << "bar"; raw_ostream &llvm::errs() { // Set standard error to be unbuffered by default. static raw_fd_ostream S(STDERR_FILENO, false, true); return S; } /// nulls() - This returns a reference to a raw_ostream which discards output. raw_ostream &llvm::nulls() { static raw_null_ostream S; return S; } //===----------------------------------------------------------------------===// // raw_string_ostream //===----------------------------------------------------------------------===// raw_string_ostream::~raw_string_ostream() { flush(); } void raw_string_ostream::write_impl(const char *Ptr, size_t Size) { OS.append(Ptr, Size); } //===----------------------------------------------------------------------===// // raw_svector_ostream //===----------------------------------------------------------------------===// uint64_t raw_svector_ostream::current_pos() const { return OS.size(); } void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) { OS.append(Ptr, Ptr + Size); } void raw_svector_ostream::pwrite_impl(const char *Ptr, size_t Size, uint64_t Offset) { memcpy(OS.data() + Offset, Ptr, Size); } //===----------------------------------------------------------------------===// // raw_null_ostream //===----------------------------------------------------------------------===// raw_null_ostream::~raw_null_ostream() { #ifndef NDEBUG // ~raw_ostream asserts that the buffer is empty. This isn't necessary // with raw_null_ostream, but it's better to have raw_null_ostream follow // the rules than to change the rules just for raw_null_ostream. flush(); #endif } void raw_null_ostream::write_impl(const char *Ptr, size_t Size) { } uint64_t raw_null_ostream::current_pos() const { return 0; } void raw_null_ostream::pwrite_impl(const char *Ptr, size_t Size, uint64_t Offset) {}