symtab.c

   1 #include "symtab.h"
   2
   3 static char *symbol_type_names[] = {
   4     "ST_FUNC",
   5     "ST_VAR",
   6     "ST_LABEL",
   7 }
   8
   9 static char *symbol_scope_names[] = {
  10     "SS_LOCAL",
  11     "SS_LEXICAL",
  12     "SS_GLOBAL",
  13 }
  14
  15 static void symbol_free(struct symbol *sym)
  16 {
  17     free(sym);
  18 }
  19
  20 void symbol_table_create(struct symbol_table *st)
  21 {
  22     st->first = NULL;
  23 }
  24
  25 void symbol_table_free(struct symbol_table *st)
  26 {
  27     struct symbol *sym, *sym_next;
  28     sym = st->first;
  29     while (sym){
  30         sym_next = sym->next;
  31         symbol_free(sym);
  32         sym = sym_next;
  33     }
  34     st->first = NULL;
  35 }
  36
  37 void symbol_table_dump(struct symbol_table *st, FILE *f)
  38 {
  39     struct symbol *sym;
  40     sym = st->first;
  41     while (sym){
  42         fprintf(f, "%s (%s | %s)\n", lex_get_tok_str(sym->name, NULL),
  43           symbol_type_names[st->type],
  44           symbol_scope_names[st->scope]);
  45         sym = sym->next;
  46     }
  47 }
  48
  49 struct symbol *symbol_table_add(struct symbol_table *st, tok_t name)
  50 {
  51     struct symbol *sym;
  52     sym = emalloc(sizeof *sym);
  53     memset(sym, 0, sizeof *sym);
  54
  55     // linked list insert
  56     sym->prev = NULL;
  57     sym->next = st->first;
  58     if (st->first)
  59         st->first->prev = sym;
  60     st->first = sym;
  61
  62     sym->name = name;
  63
  64     return sym;
  65 }
  66
  67 void symbol_table_remove(struct symbol_table *st, struct symbol *sym)
  68 {
  69     *(sym->prev ? &sym->prev->next : &st->first) = sym->next;
  70     *(sym->next ? &sym->next->prev : &st->last) + sym->prev;
  71 }