1 /*

     2  * (c) 2005 Mario de Sousa

     3  *

     4  * Offered to the public under the terms of the GNU General Public License

     5  * as published by the Free Software Foundation; either version 2 of the

     6  * License, or (at your option) any later version.

     7  *

     8  * This program is distributed in the hope that it will be useful, but

     9  * WITHOUT ANY WARRANTY; without even the implied warranty of

    10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

    11  * Public License for more details.

    12  *

    13  * This code is made available on the understanding that it will not be

    14  * used in safety-critical situations without a full and competent review.

    15  */

    16 

    17 /*

    18  * An IEC 61131-3 IL and ST compiler.

    19  *

    20  * Based on the

    21  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

    22  *

    23  */

    24 

    25 

    26 /*

    27  * A generic symbol table that allows duplicate values.

    28  *

    29  * This is used to create a symbol table of previously defined

    30  * functions. Duplicate are allowed since the standard permits function\

    31  * overloading in the standard library.

    32  */

    33 

    34 

    35 

    36 #ifndef _DSYMTABLE_HH

    37 #define _DSYMTABLE_HH

    38 

    39 #include "../absyntax/absyntax.hh"

    40 

    41 #include <map>

    42 #include <string>

    43 

    44 

    45 

    46 

    47 template<typename value_type, value_type null_value> class dsymtable_c {

    48   /* Case insensitive string compare copied from

    49    * "The C++ Programming Language" - 3rd Edition

    50    * by Bjarne Stroustrup, ISBN 0201889544.

    51    */

    52   class nocase_c {

    53     public:

    54       bool operator() (const std::string& x, const std::string& y) const {

    55         std::string::const_iterator ix = x.begin();

    56         std::string::const_iterator iy = y.begin();

    57 

    58         for(; (ix != x.end()) && (iy != y.end()) && (toupper(*ix) == toupper(*iy)); ++ix, ++iy);

    59         if (ix == x.end()) return (iy != y.end());

    60         if (iy == y.end()) return false;

    61         return (toupper(*ix) < toupper(*iy));

    62       };

    63   };

    64 

    65   public:

    66     typedef value_type value_t;

    67 

    68   private:

    69     /* Comparison between identifiers must ignore case, therefore the use of nocase_c */

    70     typedef std::multimap<std::string, value_t, nocase_c> base_t;

    71     base_t _base;

    72 

    73   public:

    74   typedef typename base_t::iterator iterator;

    75   typedef typename base_t::const_iterator const_iterator;

    76   typedef typename base_t::reverse_iterator reverse_iterator;

    77   typedef typename base_t::const_reverse_iterator const_reverse_iterator;

    78 

    79   private:

    80     void reset(void); /* clear all entries... */

    81 

    82   public:

    83     dsymtable_c(void) {};

    84 

    85     void insert(const char *identifier_str, value_t value);

    86     void insert(const symbol_c *symbol, value_t value);

    87 

    88     /* Search for an entry. Will return end_value() if not found */

    89     value_t end_value(void) {return null_value;}

    90     value_t find_value(const char *identifier_str);

    91     value_t find_value(const symbol_c *symbol);

    92 

    93     iterator find(const char *identifier_str) {return _base.find(identifier_str);}

    94 

    95   /* iterators pointing to beg/end of map... */

    96     iterator begin() 			{return _base.begin();}

    97     const_iterator begin() const	{return _base.begin();}

    98     iterator end()			{return _base.end();}

    99     const_iterator end() const 		{return _base.end();}

   100     reverse_iterator rbegin()		{return _base.rbegin();}

   101     const_reverse_iterator rbegin() const {return _base.rbegin();}

   102     reverse_iterator rend() 		{return _base.rend();}

   103     const_reverse_iterator rend() const	{return _base.rend();}

   104 

   105     /* debuging function... */

   106     void print(void);

   107 };

   108 

   109 

   110 

   111 /* Templates must include the source into the code! */

   112 #include "dsymtable.cc"

   113 

   114 #endif /*  _DSYMTABLE_HH */