source/loader.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/strings/format.h>
   3 #include "except.h"
   4 #include "loader.h"
   5 #include "type.h"
   6
   7 using namespace std;
   8
   9 namespace {
  10
  11 int signature_match(char s, char a)
  12 {
  13         if(s==a)
  14                 return 3;
  15         if(s==Msp::DataFile::IntType::signature && a==Msp::DataFile::FloatType::signature)
  16                 return 1;
  17         return 0;
  18 }
  19
  20 int signature_match(const string &st_sig, const string &act_sig)
  21 {
  22         if(act_sig=="*")
  23                 return 1;
  24         else if(act_sig.size()==2 && act_sig[1]=='*')
  25         {
  26                 int match = 3;
  27                 for(auto i=st_sig.begin(); (i!=st_sig.end() && match); ++i)
  28                         match = min(match, signature_match(*i, act_sig[0]));
  29
  30                 return match;
  31         }
  32         else if(st_sig.size()==act_sig.size())
  33         {
  34                 int match = 3;
  35                 for(unsigned i=0; (i<st_sig.size() && match); ++i)
  36                         match = min(match, signature_match(st_sig[i], act_sig[i]));
  37
  38                 return match ? match+1 : 0;
  39         }
  40         else
  41                 return 0;
  42 }
  43
  44 }
  45
  46
  47 namespace Msp {
  48 namespace DataFile {
  49
  50 Loader::Loader():
  51         actions(0),
  52         cur_st(0),
  53         direct(false),
  54         check_sub_loads(false)
  55 { }
  56
  57 void Loader::load(Parser &p)
  58 {
  59         if(!actions)
  60                 throw logic_error("no actions");
  61
  62         while(p)
  63         {
  64                 if(p.peek(0))
  65                         load_direct(p, 0);
  66                 else if(p)  // Peek may have processed an __end, so recheck goodness
  67                 {
  68                         // Parse in raw mode so we can peek immediately after a mode change
  69                         Statement st = p.parse(true);
  70                         if(st.valid && !st.control)
  71                                 load_statement(st);
  72                 }
  73         }
  74         finish();
  75 }
  76
  77 void Loader::load(const Statement &st)
  78 {
  79         if(!actions)
  80                 throw logic_error("no actions");
  81
  82         for(const Statement &s: st.sub)
  83                 load_statement(s);
  84         finish();
  85 }
  86
  87 void Loader::load_direct(Parser &p, unsigned l)
  88 {
  89         SetForScope<Parser *> set_parser(cur_parser, &p);
  90         SetForScope<unsigned> set_level(cur_level, l);
  91
  92         while(p)
  93         {
  94                 const StatementKey *key = p.peek(l);
  95                 if(!key)
  96                         break;
  97
  98                 LoaderAction *act = find_action(*key);
  99                 if(act)
 100                 {
 101                         SetFlag set_direct(direct);
 102                         if(!p.parse_and_load(l, *this, *act))
 103                                 throw logic_error("direct load failed");
 104                 }
 105                 else
 106                         load_statement(p.parse());
 107         }
 108 }
 109
 110 void Loader::load_statement(const Statement &st)
 111 {
 112         SetForScope<const Statement *> set_cst(cur_st, &st);
 113
 114         try
 115         {
 116                 StatementKey key(st.keyword, st.get_signature());
 117
 118                 if(!aux_loaders.empty() && !has_action(key))
 119                 {
 120                         for(Loader *l: aux_loaders)
 121                                 if(l->has_action(key))
 122                                         return l->load_statement(st);
 123                 }
 124
 125                 LoaderAction *act = find_action(key);
 126                 if(act)
 127                 {
 128                         sub_loaded = false;
 129                         act->execute(*this, st);
 130                         if(check_sub_loads && !st.sub.empty() && !sub_loaded)
 131                                 throw logic_error("substatements ignored");
 132                 }
 133         }
 134         catch(const data_error &e)
 135         {
 136                 if(e.get_source()!=st.source)
 137                         throw data_error(st.source, st.line, e);
 138                 else
 139                         throw;
 140         }
 141         catch(const exception &e)
 142         {
 143                 throw data_error(st.source, st.line, e);
 144         }
 145 }
 146
 147 void Loader::load_sub_with(Loader &ldr)
 148 {
 149         if(direct)
 150         {
 151                 ldr.load_direct(*cur_parser, cur_level+1);
 152                 ldr.finish();
 153         }
 154         else if(cur_st)
 155         {
 156                 ldr.load(*cur_st);
 157                 sub_loaded = true;
 158         }
 159         else
 160                 throw logic_error("no current statement");
 161 }
 162
 163 void Loader::set_actions(ActionMap &a)
 164 {
 165         if(actions)
 166                 throw logic_error("actions already set");
 167
 168         actions = &a;
 169         if(a.empty())
 170                 init_actions();
 171 }
 172
 173 void Loader::add(const string &kwd, LoaderAction *act)
 174 {
 175         if(!actions)
 176                 actions = &local_actions;
 177
 178         StatementKey key(kwd, (act ? act->get_signature() : "*"));
 179         ActionMap::iterator i = actions->find(key);
 180         if(i!=actions->end())
 181         {
 182                 delete i->second;
 183                 i->second = act;
 184         }
 185         else
 186                 (*actions)[key] = act;
 187 }
 188
 189 void Loader::add_auxiliary_loader(Loader &ldr)
 190 {
 191         aux_loaders.push_back(&ldr);
 192 }
 193
 194 bool Loader::has_action(const StatementKey &key) const
 195 {
 196         if(!actions)
 197                 return false;
 198
 199         auto i = actions->lower_bound(StatementKey(key.keyword, string()));
 200         for(; (i!=actions->end() && i->first.keyword==key.keyword); ++i)
 201                 if(signature_match(key.signature, i->first.signature))
 202                         return true;
 203         return false;
 204 }
 205
 206 LoaderAction *Loader::find_action(const StatementKey &key) const
 207 {
 208         if(!actions)
 209                 return 0;
 210
 211         auto begin = actions->lower_bound(StatementKey(key.keyword, string()));
 212         auto end = actions->upper_bound(StatementKey(key.keyword, "~"));
 213
 214         if(begin==end)
 215                 throw unknown_keyword(key.keyword);
 216
 217         LoaderAction *act = 0;
 218         int match = 0;
 219         for(auto i=begin; i!=end; ++i)
 220         {
 221                 int m = signature_match(key.signature, i->first.signature);
 222                 if(m>match)
 223                 {
 224                         act = i->second;
 225                         match = m;
 226                 }
 227         }
 228
 229         if(!match)
 230                 throw invalid_signature(key.keyword, key.signature);
 231
 232         return act;
 233 }
 234
 235 const string &Loader::get_source() const
 236 {
 237         if(!cur_st)
 238                 throw logic_error("no current statement");
 239         return cur_st->source;
 240 }
 241
 242 const string &Loader::get_keyword() const
 243 {
 244         if(!cur_st)
 245                 throw logic_error("no current statement");
 246         return cur_st->keyword;
 247 }
 248
 249
 250 Loader::ActionMap::~ActionMap()
 251 {
 252         for(const auto &kvp: *this)
 253                 delete kvp.second;
 254 }
 255
 256 } // namespace DataFile
 257 } // namespace Msp