libsecurity_codesigning/antlr2/src/InputBuffer.cpp

   1 /* ANTLR Translator Generator
   2  * Project led by Terence Parr at http://www.jGuru.com
   3  * Software rights: http://www.antlr.org/license.html
   4  *
   5  * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/src/InputBuffer.cpp#2 $
   6  */
   7
   8 #include "antlr/config.hpp"
   9 #include "antlr/InputBuffer.hpp"
  10
  11 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
  12 namespace antlr {
  13 #endif
  14
  15 /** Ensure that the character buffer is sufficiently full */
  16 void InputBuffer::fill(unsigned int amount)
  17 {
  18         syncConsume();
  19         // Fill the buffer sufficiently to hold needed characters
  20         while (queue.entries() < amount + markerOffset)
  21         {
  22                 // Append the next character
  23                 queue.append(getChar());
  24         }
  25 }
  26
  27 /** get the current lookahead characters as a string
  28  * @warning it may treat 0 and EOF values wrong
  29  */
  30 ANTLR_USE_NAMESPACE(std)string InputBuffer::getLAChars( void ) const
  31 {
  32         ANTLR_USE_NAMESPACE(std)string ret;
  33
  34         for(unsigned int i = markerOffset; i < queue.entries(); i++)
  35                 ret += queue.elementAt(i);
  36
  37         return ret;
  38 }
  39
  40 /** get the current marked characters as a string
  41  * @warning it may treat 0 and EOF values wrong
  42  */
  43 ANTLR_USE_NAMESPACE(std)string InputBuffer::getMarkedChars( void ) const
  44 {
  45         ANTLR_USE_NAMESPACE(std)string ret;
  46
  47         for(unsigned int i = 0; i < markerOffset; i++)
  48                 ret += queue.elementAt(i);
  49
  50         return ret;
  51 }
  52
  53 /** Return an integer marker that can be used to rewind the buffer to
  54  * its current state.
  55  */
  56 unsigned int InputBuffer::mark()
  57 {
  58         syncConsume();
  59         nMarkers++;
  60         return markerOffset;
  61 }
  62
  63 /** Rewind the character buffer to a marker.
  64  * @param mark Marker returned previously from mark()
  65  */
  66 void InputBuffer::rewind(unsigned int mark)
  67 {
  68         syncConsume();
  69         markerOffset = mark;
  70         nMarkers--;
  71 }
  72
  73 unsigned int InputBuffer::entries() const
  74 {
  75         //assert(queue.entries() >= markerOffset);
  76         return (unsigned int)queue.entries() - markerOffset;
  77 }
  78
  79 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
  80 }
  81 #endif