/***************************************************************
  SYMTAB.C

     This file containts SYMBOL TABLE routines of ZUBR.

     PART OF : ZUBR - Parsers generator for multiple syntax
                      language compilers .

     COMPILE : .

     NOTE    : NONE .

     Copyright (C) 1995 - 2026  by Andrey V.Kosteltsev.
     All Rights Reserved.
 ***************************************************************/
/*
  This file contant RUSSIAN letters( code-page: UTF-8 )
 ***************************************************************/

#include <defs.h>

#ifndef __NO_COMPILE


/* TABLE_SIZE is the number of entries in the symbol table. */
/* TABLE_SIZE must be a power of two.                       */

#define TABLE_SIZE 2048

bucket **symbol_table;
bucket  *first_symbol;
bucket  *last_symbol;

int hash( __mpu_char16_t *name )
/***************************************************************

 Description        : find unique number in symbol table

 Concepts           : excellent !

 Use Global Variable:

 Use Functions      :

 Parameters         : char *name

 Return             : int k;

 ***************************************************************/
{
  register __mpu_char16_t *s;
  register int           c, k;

  if( !name || *name == 0 )
  {
    done( 2 );
  }
  s = name;
  k = *s;
  while( (c = *++s) ) k = (31*k + c) & (TABLE_SIZE - 1);

  return( k );

} /*******  End of hash( char *name )  *************************/


bucket * make_bucket( __mpu_char16_t *name )
/***************************************************************

 Description        : allocate memory for symbol

 Concepts           :

 Use Global Variable:

 Use Functions      :

 Parameters         : char *name

 Return             : bucket *bp

 ***************************************************************/
{
  register bucket *bp;

  if( !name )
  {
    done( 2 );
  }
  bp = (bucket *)MALLOC( sizeof( bucket ) );
  if( bp == 0 ) no_space();

  bp->link   = 0;
  bp->next   = 0;

  bp->name = (__mpu_char16_t *)MALLOC( (mpu_str16len( name ) + 1) *
                          sizeof(__mpu_char16_t) );
  if( bp->name == 0 ) no_space();
  mpu_str16cpy( bp->name, name );

  bp->tag    = 0;
  bp->value  = UNDEFINED;
  bp->index  = 0;
  bp->prec   = 0;
  bp->class  = UNKNOWN;
  bp->assoc  = TOKEN;

  return( bp );

} /*******  End of make_bucket( char *name )  ******************/


bucket * lookup( __mpu_char16_t *name )
/***************************************************************

 Description        : find symbol in symbol table
                      if symbol not found,
                      then (for its) allocate memory (use make_bucket ())
                      and include in symbol table

 Concepts           :

 Use Global Variable: bucket *last_symbol;         | this file

 Use Functions      :

 Parameters         : char *name

 Return             : bucket *bp

 ***************************************************************/
{
  register bucket *bp, **bpp;

  bpp = symbol_table + hash( name );
  bp = *bpp;

  while( bp )
  {
    if( mpu_str16cmp( name, bp->name ) == 0 ) return( bp );
    bpp = &bp->link; /* link для связи цепочки по
                  одному индексу в symbol_table[] */
    bp = *bpp;
    /*
      См.:
        David Gries, Compiler Construction
                 for Digital Computers,
        Cornell University, 1971.

        Д.Грис, Конструирование компиляторов для цифровых
              вычислительных машин,
        Пер. с англ., Е.Б.Докшитской и др., 
        Под ред. Ю.М.Баяковского, М.: Мир, 1975.

      п. 9.3.2. Метод цепочек, стр. 252.
     */
  }

  *bpp = bp = make_bucket( name ); /* make and insert into symbol_table */
  last_symbol->next = bp;
  last_symbol       = bp;

  return( bp );

} /*******  End of lookup( char *name )  ***********************/


void create_symbol_table( void )
/***************************************************************

 Description        : allocate memory for symbol_table
                      and make symbol u"error"

 Concepts           :

 Use Global Variable: bucket *first_symbol;        | this file
                      bucket *last_symbol;         | this file

 Use Functions      :

 Parameters         : [void]

 Return             : [void]

 ***************************************************************/
{
  register int     i;
  register bucket *bp;

  symbol_table = (bucket **)MALLOC( TABLE_SIZE*sizeof( bucket * ) );
  if( symbol_table == 0 ) no_space();
  for( i = 0; i < TABLE_SIZE; i++ ) symbol_table[i] = 0;

  bp = make_bucket( (__mpu_char16_t *)MPU_UCS2( "error" ) );
  bp->index    = 1;
  bp->class    = TERM;

  first_symbol = bp;
  last_symbol  = bp;

  symbol_table[hash( (__mpu_char16_t *)MPU_UCS2( "error" ) )] = bp;

} /*******  End of create_symbol_table( void )  ****************/


void free_symbol_table( void )
/***************************************************************

 Description        : free memory for symbol_table

 Concepts           :

 Use Global Variable:

 Use Functions      :

 Parameters         : [void]

 Return             : [void]

 ***************************************************************/
{
  FREE( symbol_table );
  symbol_table = 0;

} /*******  End of free_symbol_table( void )  ******************/


void free_symbols( void )
/***************************************************************

 Description        : free memory for all symbols in list

 Concepts           :

 Use Global Variable: bucket *first_symbol;        | this file

 Use Functions      :

 Parameters         : [void]

 Return             : [void]

 ***************************************************************/
{
  register bucket *p, *q;

  for( p = first_symbol; p; p = q )
  {
    q = p->next;
    /* TODO ADD FREE(name) and other */
    FREE( p );
  }

} /*******  End of free_symbols( void )  ***********************/

#endif /* __NO_COMPILE */

/******************  END OF FILE SYMTAB.C  *********************/