source/parser.cpp

   1 #include <msp/strings/format.h>
   2 #include "binaryparser.h"
   3 #include "except.h"
   4 #include "parser.h"
   5 #include "statement.h"
   6 #include "textparser.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace DataFile {
  12
  13 Parser::Parser(IO::Base &i, const string &s):
  14         in(i),
  15         main_src(s),
  16         src(s),
  17         good(true),
  18         mode(new TextParser(in, src))
  19 { }
  20
  21 Parser::~Parser()
  22 {
  23         delete mode;
  24 }
  25
  26 Statement Parser::parse(bool raw)
  27 {
  28         if(!good)
  29                 throw logic_error("Parser::parse() !good");
  30
  31         try
  32         {
  33                 while(1)
  34                 {
  35                         Statement st = mode->parse();
  36                         if(!st.keyword.compare(0, 2, "__"))
  37                         {
  38                                 st.control = true;
  39                                 process_control_statement(st);
  40                         }
  41
  42                         if(raw || !st.control)
  43                                 return st;
  44                         else if(!good)  // This will occur with an __end statement
  45                                 return Statement();
  46                 }
  47         }
  48         catch(const exception &e)
  49         {
  50                 good = false;
  51                 if(dynamic_cast<const data_error *>(&e))
  52                         throw;
  53                 else
  54                         throw data_error(src, in.get_line_number(), e);
  55         }
  56 }
  57
  58 void Parser::process_control_statement(const Statement &st)
  59 {
  60         if(st.keyword=="__bin")
  61         {
  62                 delete mode;
  63                 mode = new BinaryParser(in, src);
  64
  65                 while(in.peek()=='\n')
  66                         in.get();
  67         }
  68         else if(st.keyword=="__text")
  69         {
  70                 delete mode;
  71                 mode = new TextParser(in, src);
  72         }
  73         else if(st.keyword=="__z")
  74                 in.set_decompress();
  75         else if(st.keyword=="__src")
  76         {
  77                 string s = st.args[0].get<string>();
  78                 if(s.empty())
  79                         src = main_src;
  80                 else
  81                         src = format("%s[%s]", main_src, s);
  82         }
  83         else if(st.keyword=="__end")
  84                 good = false;
  85         else
  86                 mode->process_control_statement(st);
  87 }
  88
  89 const StatementKey *Parser::peek(unsigned level)
  90 {
  91         while(good)
  92         {
  93                 const StatementKey *key = mode->peek(level);
  94                 if(key && !key->keyword.compare(0, 2, "__"))
  95                         process_control_statement(mode->parse());
  96                 else
  97                         return key;
  98         }
  99
 100         return 0;
 101 }
 102
 103 bool Parser::parse_and_load(unsigned level, Loader &ldr, const LoaderAction &act)
 104 {
 105         // Peek first to get any control statements processed
 106         peek(level);
 107         return mode->parse_and_load(level, ldr, act);
 108 }
 109
 110 } // namespace DataFile
 111 } // namespace Msp