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|
//===--- 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/Format.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/system_error.h"
#include <cctype>
#include <cerrno>
#include <sys/stat.h>
#include <sys/types.h>
#if defined(HAVE_UNISTD_H)
# include <unistd.h>
#endif
#if defined(HAVE_FCNTL_H)
# include <fcntl.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>
#include <fcntl.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
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 == 0 && Size == 0) ||
(Mode != Unbuffered && BufferStart && Size)) &&
"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 = 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 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[20];
char *EndPtr = NumberBuffer+sizeof(NumberBuffer);
char *CurPtr = EndPtr;
while (N) {
uintptr_t x = N % 16;
*--CurPtr = (x < 10 ? '0' + x : 'a' + x - 10);
N /= 16;
}
return write(CurPtr, EndPtr-CurPtr);
}
raw_ostream &raw_ostream::write_escaped(StringRef Str,
bool UseHexEscapes) {
for (unsigned i = 0, e = Str.size(); i != e; ++i) {
unsigned char c = Str[i];
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!
int fpcl = _fpclass(N);
// negative zero
if (fpcl == _FPCLASS_NZ)
return *this << "-0.000000e+00";
char buf[16];
unsigned len;
len = snprintf(buf, sizeof(buf), "%e", N);
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)) {
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;
}
}
/// 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
//===----------------------------------------------------------------------===//
/// 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::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
unsigned Flags)
: Error(false), UseAtomicWrites(false), pos(0)
{
assert(Filename != 0 && "Filename is null");
// Verify that we don't have both "append" and "excl".
assert((!(Flags & F_Excl) || !(Flags & F_Append)) &&
"Cannot specify both 'excl' and 'append' file creation flags!");
ErrorInfo.clear();
// 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[0] == '-' && Filename[1] == 0) {
FD = STDOUT_FILENO;
// If user requested binary then put stdout into binary mode if
// possible.
if (Flags & F_Binary)
sys::Program::ChangeStdoutToBinary();
// Close stdout when we're done, to detect any output errors.
ShouldClose = true;
return;
}
int OpenFlags = O_WRONLY|O_CREAT;
#ifdef O_BINARY
if (Flags & F_Binary)
OpenFlags |= O_BINARY;
#endif
if (Flags & F_Append)
OpenFlags |= O_APPEND;
else
OpenFlags |= O_TRUNC;
if (Flags & F_Excl)
OpenFlags |= O_EXCL;
while ((FD = open(Filename, OpenFlags, 0664)) < 0) {
if (errno != EINTR) {
ErrorInfo = "Error opening output file '" + std::string(Filename) + "'";
ShouldClose = false;
return;
}
}
// Ok, we successfully opened the file, so it'll need to be closed.
ShouldClose = true;
}
/// 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::raw_fd_ostream(int fd, bool shouldClose, bool unbuffered)
: raw_ostream(unbuffered), FD(fd),
ShouldClose(shouldClose), Error(false), UseAtomicWrites(false) {
#ifdef O_BINARY
// Setting STDOUT and STDERR to binary mode is necessary in Win32
// to avoid undesirable linefeed conversion.
if (fd == STDOUT_FILENO || fd == STDERR_FILENO)
setmode(fd, O_BINARY);
#endif
// Get the starting position.
off_t loc = ::lseek(FD, 0, SEEK_CUR);
if (loc == (off_t)-1)
pos = 0;
else
pos = static_cast<uint64_t>(loc);
}
raw_fd_ostream::~raw_fd_ostream() {
if (FD >= 0) {
flush();
if (ShouldClose)
while (::close(FD) != 0)
if (errno != EINTR) {
error_detected();
break;
}
}
#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.");
}
void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
assert(FD >= 0 && "File already closed.");
pos += Size;
do {
ssize_t ret;
// Check whether we should attempt to use atomic writes.
if (LLVM_LIKELY(!UseAtomicWrites)) {
ret = ::write(FD, Ptr, Size);
} else {
// Use ::writev() where available.
#if defined(HAVE_WRITEV)
const void *Addr = static_cast<const void *>(Ptr);
struct iovec IOV = {const_cast<void *>(Addr), Size };
ret = ::writev(FD, &IOV, 1);
#else
ret = ::write(FD, Ptr, Size);
#endif
}
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();
while (::close(FD) != 0)
if (errno != EINTR) {
error_detected();
break;
}
FD = -1;
}
uint64_t raw_fd_ostream::seek(uint64_t off) {
flush();
pos = ::lseek(FD, off, SEEK_SET);
if (pos != off)
error_detected();
return 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 exists, forcing error
// detection. If you don't want this behavior, don't use outs().
static raw_fd_ostream S(STDOUT_FILENO, true);
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
//===----------------------------------------------------------------------===//
// The raw_svector_ostream implementation uses the SmallVector itself as the
// buffer for the raw_ostream. We guarantee that the raw_ostream buffer is
// always pointing past the end of the vector, but within the vector
// capacity. This allows raw_ostream to write directly into the correct place,
// and we only need to set the vector size when the data is flushed.
raw_svector_ostream::raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {
// Set up the initial external buffer. We make sure that the buffer has at
// least 128 bytes free; raw_ostream itself only requires 64, but we want to
// make sure that we don't grow the buffer unnecessarily on destruction (when
// the data is flushed). See the FIXME below.
OS.reserve(OS.size() + 128);
SetBuffer(OS.end(), OS.capacity() - OS.size());
}
raw_svector_ostream::~raw_svector_ostream() {
// FIXME: Prevent resizing during this flush().
flush();
}
/// 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 raw_svector_ostream::resync() {
assert(GetNumBytesInBuffer() == 0 && "Didn't flush before mutating vector");
if (OS.capacity() - OS.size() < 64)
OS.reserve(OS.capacity() * 2);
SetBuffer(OS.end(), OS.capacity() - OS.size());
}
void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) {
// If we're writing bytes from the end of the buffer into the smallvector, we
// don't need to copy the bytes, just commit the bytes because they are
// already in the right place.
if (Ptr == OS.end()) {
assert(OS.size() + Size <= OS.capacity() && "Invalid write_impl() call!");
OS.set_size(OS.size() + Size);
} else {
assert(GetNumBytesInBuffer() == 0 &&
"Should be writing from buffer if some bytes in it");
// Otherwise, do copy the bytes.
OS.append(Ptr, Ptr+Size);
}
// Grow the vector if necessary.
if (OS.capacity() - OS.size() < 64)
OS.reserve(OS.capacity() * 2);
// Update the buffer position.
SetBuffer(OS.end(), OS.capacity() - OS.size());
}
uint64_t raw_svector_ostream::current_pos() const {
return OS.size();
}
StringRef raw_svector_ostream::str() {
flush();
return StringRef(OS.begin(), OS.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;
}
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