symbol_table.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include "symbol_table.h"
   5
   6 Symbol *
   7 symbol_new(char const * name)
   8 {
   9     Symbol * symbol = (Symbol *) malloc (sizeof(Symbol));
  10     symbol->type = NONE_TYPE;
  11     value_set(&symbol->value, symbol->type, NULL);
  12     symbol->next = NULL;
  13
  14     if (name != NULL)
  15         symbol->name = strdup(name);
  16      else
  17         symbol->name = NULL;
  18
  19     return symbol;
  20 }
  21
  22 /* Insere um simbolo na tabela indicada.
  23  * Caso o simbolo ja exista, a memoria do
  24  * simbolo do parametro sera liberada.
  25  * Returns: O simbolo passado como parametro,
  26  * caso este ainda nao esteja na tabela,
  27  * ou um ponteiro para o simbolo encontrado.
  28  */
  29 Symbol *
  30 symbol_insert(Symbol *symtab, Symbol *symbol)
  31 {
  32     Symbol *sym;
  33
  34     if (symbol == NULL)
  35         return NULL;
  36
  37     sym = symbol_lookup(symtab->next, symbol->name);
  38
  39     if (sym != NULL) {
  40         free(symbol->name);
  41         free(symbol);
  42         return sym;
  43     }
  44
  45     //printf("symbol %x (next %x)\nsym    %x\n", symbol, symbol->next, sym);
  46
  47     symbol->next = symtab->next;
  48     symtab->next = symbol;
  49
  50     symbol_table_dump(symtab);
  51     //printf("symbol %x (next %x)\nsym    %x\n", symbol, symbol->next, sym);
  52     return symbol;
  53 }
  54
  55 Symbol *
  56 symbol_lookup(Symbol *symtab, char const *name)
  57 {
  58     Symbol *temp;
  59
  60     for (temp = symtab; temp != NULL; temp = temp->next) {
  61         if (!strcmp (temp->name, name))
  62             return temp;
  63     }
  64
  65     return temp;
  66 }
  67
  68 void
  69 symbol_table_destroy(Symbol *symtab)
  70 {
  71     Symbol *first;
  72     Symbol *to_kill;
  73     first = symtab->next;
  74     symtab->next = NULL;
  75
  76     while (first != NULL) {
  77         to_kill = first;
  78         first = first->next;
  79         if (to_kill->name != NULL)
  80             free(to_kill->name);
  81         free(to_kill);
  82     }
  83 }
  84
  85 void
  86 symbol_print(Symbol *symbol)
  87 {
  88     if (symbol == NULL) {
  89         printf("NULL\n\n");
  90         return;
  91     }
  92
  93     printf("Symbol: %x\n", symbol);
  94     printf("name: %s\n", symbol->name);
  95     printf("type: %d\n", symbol->type);
  96     printf("value:");
  97     value_print(&symbol->value, symbol->type);
  98     printf("\nnext: %x\n\n", symbol->next);
  99 }
 100
 101 void
 102 symbol_table_dump(Symbol *symtab)
 103 {
 104     Symbol *temp = symtab;
 105
 106     for (temp = symtab->next; temp != NULL; temp = temp->next)
 107         symbol_print(temp);
 108 }