mem.c

   1 #include <stdlib.h>
   2 #include "lambda.h"
   3
   4 void lambda_free(struct lambda *t)
   5 {
   6         if(t != NULL){
   7                 if(t->refcount == 1){
   8                         switch(t->which){
   9                         case lambda_ident:
  10                                 free(t->data.identifier.ident);
  11                                 break;
  12                         case lambda_abs:
  13                                 free(t->data.abstraction.ident);
  14                                 lambda_free(t->data.abstraction.expr);
  15                                 break;
  16                         case lambda_app:
  17                                 lambda_free(t->data.application.expr1);
  18                                 lambda_free(t->data.application.expr2);
  19                                 break;
  20                         }
  21                         free(t);
  22                 } else {
  23                         t->refcount--;
  24                 }
  25         }
  26 }
  27
  28 struct lambda *copy(struct lambda *t)
  29 {
  30         struct lambda *c = malloc(sizeof (struct lambda));
  31         c->which = t->which;
  32         switch(t->which){
  33         case lambda_ident:
  34                 c->data.identifier.ident = strdup(t->data.identifier.ident);
  35                 c->data.identifier.revision = t->data.identifier.revision;
  36                 break;
  37         case lambda_abs:
  38                 c->data.abstraction.ident = strdup(t->data.abstraction.ident);
  39                 c->data.abstraction.strict = t->data.abstraction.strict;
  40                 c->data.abstraction.expr = copy(t->data.abstraction.expr);
  41                 c->data.abstraction.revision = t->data.abstraction.revision;
  42                 break;
  43         case lambda_app:
  44                 c->data.application.expr1 = copy(t->data.application.expr1);
  45                 c->data.application.expr2 = copy(t->data.application.expr2);
  46                 break;
  47         }
  48         return c;
  49 }
  50