llvm-6502/lib/Support/FormattedStream.cpp

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//===-- llvm/Support/FormattedStream.cpp - Formatted streams ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the implementation of formatted_raw_ostream.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormattedStream.h"
using namespace llvm;
/// CountColumns - Examine the given char sequence and figure out which
/// column we end up in after output.
///
static unsigned CountColumns(unsigned Column, const char *Ptr, size_t Size) {
// Keep track of the current column by scanning the string for
// special characters
for (const char *End = Ptr + Size; Ptr != End; ++Ptr) {
++Column;
if (*Ptr == '\n' || *Ptr == '\r')
Column = 0;
else if (*Ptr == '\t')
// Assumes tab stop = 8 characters.
Column += (8 - (Column & 0x7)) & 0x7;
}
return Column;
}
/// ComputeColumn - Examine the current output and figure out which
/// column we end up in after output.
void formatted_raw_ostream::ComputeColumn(const char *Ptr, size_t Size) {
// If our previous scan pointer is inside the buffer, assume we already
// scanned those bytes. This depends on raw_ostream to not change our buffer
// in unexpected ways.
if (Ptr <= Scanned && Scanned <= Ptr + Size) {
// Scan all characters added since our last scan to determine the new
// column.
ColumnScanned = CountColumns(ColumnScanned, Scanned,
Size - (Scanned - Ptr));
} else
ColumnScanned = CountColumns(ColumnScanned, Ptr, Size);
// Update the scanning pointer.
Scanned = Ptr + Size;
}
/// PadToColumn - Align the output to some column number.
///
/// \param NewCol - The column to move to.
///
formatted_raw_ostream &formatted_raw_ostream::PadToColumn(unsigned NewCol) {
// Figure out what's in the buffer and add it to the column count.
ComputeColumn(getBufferStart(), GetNumBytesInBuffer());
// Output spaces until we reach the desired column.
indent(std::max(int(NewCol - ColumnScanned), 1));
return *this;
}
void formatted_raw_ostream::write_impl(const char *Ptr, size_t Size) {
// Figure out what's in the buffer and add it to the column count.
ComputeColumn(Ptr, Size);
// Write the data to the underlying stream (which is unbuffered, so
// the data will be immediately written out).
TheStream->write(Ptr, Size);
// Reset the scanning pointer.
Scanned = 0;
}
/// fouts() - This returns a reference to a formatted_raw_ostream for
/// standard output. Use it like: fouts() << "foo" << "bar";
formatted_raw_ostream &llvm::fouts() {
static formatted_raw_ostream S(outs());
return S;
}
/// ferrs() - This returns a reference to a formatted_raw_ostream for
/// standard error. Use it like: ferrs() << "foo" << "bar";
formatted_raw_ostream &llvm::ferrs() {
static formatted_raw_ostream S(errs());
return S;
}
/// fdbgs() - This returns a reference to a formatted_raw_ostream for
/// the debug stream. Use it like: fdbgs() << "foo" << "bar";
formatted_raw_ostream &llvm::fdbgs() {
static formatted_raw_ostream S(dbgs());
return S;
}