lib/includable-lexer.cc

   1 /*
   2   includable-lexer.cc -- implement Includable_lexer
   3
   4   source file of the LilyPond music typesetter
   5
   6   (c) 1997 Han-Wen Nienhuys <hanwen@stack.nl>
   7 */
   8 #include "includable-lexer.hh"
   9 #include "source-file.hh"
  10 #include "source.hh"
  11
  12 Includable_lexer::Includable_lexer()
  13 {
  14     yy_current_buffer = 0;
  15 }
  16
  17 /** set the  new input to s, remember old file.
  18 */
  19 void
  20 Includable_lexer::new_input(String s, Sources  * global_sources)
  21 {
  22     Source_file * sl = global_sources->get_file_l(s);
  23     if (!sl) {
  24         LexerError("can't find file");
  25         return;
  26     }
  27     char_count_stack_.push(0);
  28     if (yy_current_buffer)
  29         state_stack_.push(yy_current_buffer);
  30     cout << "[" << s<<flush;
  31     include_stack_.push(sl);
  32
  33     // ugh. We'd want to create a buffer from the bytes directly.
  34     yy_switch_to_buffer(yy_create_buffer( sl->istream_l(), sl->length_off() ));
  35 }
  36
  37 /** pop the inputstack.  conceptually this is a destructor, but it
  38   does not destruct the Source_file that Includable_lexer::new_input creates.  */
  39 bool
  40 Includable_lexer::close_input()
  41 {
  42     include_stack_.pop();
  43     char_count_stack_.pop();
  44     cout << "]"<<flush;
  45     yy_delete_buffer(yy_current_buffer );
  46     if (state_stack_.empty()) {
  47         yy_current_buffer = 0;
  48         return false;
  49     }else {
  50         yy_switch_to_buffer(state_stack_.pop());
  51         return true;
  52     }
  53 }
  54
  55 char const*
  56 Includable_lexer::here_ch_C()
  57 {
  58     if (include_stack_.empty())
  59         return 0;
  60     return include_stack_.top()->ch_C() + char_count_stack_.top();
  61 }
  62
  63 Includable_lexer::~Includable_lexer()
  64 {
  65     while (!include_stack_.empty()) {
  66         close_input();
  67     };
  68 }
  69 /**
  70   Since we don't create the buffer state from the bytes directly, we
  71   don't know about the location of the lexer. Add this as a
  72   YY_USER_ACTION */
  73 void
  74 Includable_lexer::add_lexed_char(int count)
  75 {
  76     char_count_stack_.top() += count;
  77 }
  78
  79 Source_file*
  80 Includable_lexer::source_file_l()const
  81 {
  82     return include_stack_.top();
  83 }