1 //===-- llvm/Support/FormattedStream.cpp - Formatted streams ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the implementation of formatted_raw_ostream.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Support/FormattedStream.h"
18 /// CountColumns - Examine the given char sequence and figure out which
19 /// column we end up in after output.
21 static unsigned CountColumns(unsigned Column, const char *Ptr, size_t Size) {
22 // Keep track of the current column by scanning the string for
25 for (const char *End = Ptr + Size; Ptr != End; ++Ptr) {
27 if (*Ptr == '\n' || *Ptr == '\r')
29 else if (*Ptr == '\t')
30 // Assumes tab stop = 8 characters.
31 Column += (8 - (Column & 0x7)) & 0x7;
37 /// ComputeColumn - Examine the current output and figure out which
38 /// column we end up in after output.
39 void formatted_raw_ostream::ComputeColumn() {
40 // The buffer may have been allocated underneath us.
41 if (Scanned == 0) Scanned = begin();
42 // Scan all characters added since our last scan to determine the new column.
43 ColumnScanned = CountColumns(ColumnScanned, Scanned, end() - Scanned);
44 // We're now current with everything in the buffer.
48 /// PadToColumn - Align the output to some column number.
50 /// \param NewCol - The column to move to.
51 /// \param MinPad - The minimum space to give after the most recent
52 /// I/O, even if the current column + minpad > newcol.
54 void formatted_raw_ostream::PadToColumn(unsigned NewCol) {
55 // Figure out what's in the buffer and add it to the column count.
58 // Output spaces until we reach the desired column.
59 unsigned num = NewCol - ColumnScanned;
60 if (NewCol < ColumnScanned || num < 1)
63 // Keep a buffer of spaces handy to speed up processing.
64 const char *Spaces = " "
67 assert(num < MAX_COLUMN_PAD && "Unexpectedly large column padding");
71 void formatted_raw_ostream::write_impl(const char *Ptr, size_t Size) {
72 // Figure out what's in the buffer and add it to the column count.
75 // Write the data to the underlying stream (which is unbuffered, so
76 // the data will be immediately written out).
77 TheStream->write(Ptr, Size);
79 // If this FormattedStream is unbuffered, scan the string that
80 // was just written to determine the new column.
82 // Buffered mode. The buffer is being flushed; reset the scanning
83 // position to the beginning of the buffer.
84 assert(Ptr + Size == end() && "Buffer is not being fully flushed!");
87 // Unbuffered mode. Immediately scan the string that was just
88 // written to determine the new column.
89 ColumnScanned = CountColumns(ColumnScanned, Ptr, Size);
93 /// fouts() - This returns a reference to a formatted_raw_ostream for
94 /// standard output. Use it like: fouts() << "foo" << "bar";
95 formatted_raw_ostream &llvm::fouts() {
96 static formatted_raw_ostream S(outs());
100 /// ferrs() - This returns a reference to a formatted_raw_ostream for
101 /// standard error. Use it like: ferrs() << "foo" << "bar";
102 formatted_raw_ostream &llvm::ferrs() {
103 static formatted_raw_ostream S(errs());