diff options
author | Shih-wei Liao <sliao@google.com> | 2010-02-10 11:10:31 -0800 |
---|---|---|
committer | Shih-wei Liao <sliao@google.com> | 2010-02-10 11:10:31 -0800 |
commit | e264f62ca09a8f65c87a46d562a4d0f9ec5d457e (patch) | |
tree | 59e3d57ef656cef79afa708ae0a3daf25cd91fcf /lib/Support/FormattedStream.cpp | |
download | external_llvm-e264f62ca09a8f65c87a46d562a4d0f9ec5d457e.zip external_llvm-e264f62ca09a8f65c87a46d562a4d0f9ec5d457e.tar.gz external_llvm-e264f62ca09a8f65c87a46d562a4d0f9ec5d457e.tar.bz2 |
Check in LLVM r95781.
Diffstat (limited to 'lib/Support/FormattedStream.cpp')
-rw-r--r-- | lib/Support/FormattedStream.cpp | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/Support/FormattedStream.cpp b/lib/Support/FormattedStream.cpp new file mode 100644 index 0000000..9ab3666 --- /dev/null +++ b/lib/Support/FormattedStream.cpp @@ -0,0 +1,101 @@ +//===-- 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. +/// \param MinPad - The minimum space to give after the most recent +/// I/O, even if the current column + minpad > newcol. +/// +void 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)); +} + +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; +} |