ag/symtable.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include "symtable.h"
   5
   6 #define DD
   7
   8 struct symbol *tab_new(void)
   9 {
  10         return SYMNULL;
  11 }
  12
  13 struct symbol *tab_clone(struct symbol *tab)
  14 {
  15         struct symbol *elm = tab;
  16         struct symbol *ntab = tab_new();
  17 #ifdef DD
  18         printf("tab_clone: tab(%08X)\n", tab);
  19 #endif
  20
  21         while(elm != SYMNULL) {
  22                 ntab = tab_add_symbol(ntab, elm->ident, elm->type, 0);
  23                 elm = elm->next;
  24         }
  25         return ntab;
  26 }
  27
  28 struct symbol *tab_add_symbol(struct symbol *tab, char *ident, short type, short check)
  29 {
  30         struct symbol *elm = tab;
  31         struct symbol *new_elm;
  32 #ifdef DD
  33         printf("tab_add_symbol: tab(%08X), ident(%s), type(%i), check(%i)\n", tab, ident, type, check);
  34 #endif
  35
  36         if(tab_lookup(tab, ident, type) != SYMNULL) {
  37                 if(check) {
  38                         fprintf(stderr, "Identifier doppelt vorhanden: \"%s\"\n", ident);
  39                         exit(3);
  40                 } else {
  41                         tab = tab_remove_symbol(tab, ident, type);
  42                 }
  43         }
  44
  45         new_elm = (struct symbol *) malloc(sizeof(struct symbol));
  46         new_elm->next = SYMNULL;
  47         new_elm->ident = strdup(ident);
  48         new_elm->type = type;
  49
  50         if(tab == SYMNULL) {
  51                 return new_elm;
  52         }
  53
  54         while(elm->next != SYMNULL) {
  55                 elm = elm->next;
  56         }
  57         elm->next = new_elm;
  58
  59         return tab;
  60 }
  61
  62 struct symbol *tab_lookup(struct symbol *tab, char *ident, short type)
  63 {
  64         struct symbol *elm = tab;
  65
  66         if(tab == SYMNULL) {
  67                 return SYMNULL;
  68         }
  69
  70         do {
  71                 if((elm->type == type) && (strcmp(elm->ident, ident) == 0)) {
  72                         return elm;
  73                 }
  74                 elm = elm->next;
  75         } while(elm != SYMNULL);
  76
  77         return SYMNULL;
  78 }
  79
  80 struct symbol *tab_merge(struct symbol *tab, struct symbol *to_add, short check)
  81 {
  82         struct symbol *elm = to_add;
  83         struct symbol *ntab = tab_clone(tab);
  84 #ifdef DD
  85         printf("tab_merge: tab(%08X), to_add(%08X), check(%i), ntab(%08X)\n", tab, to_add, check, ntab);
  86 #endif
  87
  88         while(elm != SYMNULL) {
  89                 ntab = tab_add_symbol(ntab, elm->ident, elm->type, check);
  90                 elm = elm->next;
  91         }
  92
  93         return ntab;
  94 }
  95
  96 struct symbol *tab_remove_symbol(struct symbol *tab, char *ident, short type)
  97 {
  98         struct symbol *elm = tab;
  99         struct symbol *previous_elm = SYMNULL;
 100
 101         while(elm != SYMNULL) {
 102                 if((elm->type == type) && (strcmp(elm->ident, ident) == 0)) {
 103                         if(previous_elm == SYMNULL) {
 104                                 tab = elm->next;
 105                         } else {
 106                                 previous_elm->next = elm->next;
 107                         }
 108                         (void)free(elm->ident);
 109                         (void)free(elm);
 110                         break;
 111                 }
 112                 previous_elm = elm;
 113                 elm = elm->next;
 114         }
 115
 116         return tab;
 117 }
 118
 119 void check(struct symbol *tab, char *ident, short type)
 120 {
 121         struct symbol *elm;
 122 #ifdef DD
 123         printf("check: tab(%08X), ident(%s), type(%i), elm(%08X)\n", tab, ident, type, elm);
 124 #endif
 125
 126         if(type == S_VAR) {
 127                 elm = tab_lookup(tab, ident, type);
 128                 if(elm != SYMNULL) {
 129                         return;
 130                 }
 131         }
 132
 133         /* keine passende variable gefunden?
 134          * => vllt gibt es ja ein passenden feldnamen */
 135         elm = tab_lookup(tab, ident, S_FIELD);
 136         if(elm == SYMNULL) {
 137                 fprintf(stderr, "Unbekannter Identifier: \"%s\"\n", ident);
 138                 exit(3);
 139         }
 140 }
 141