static Symbol *symlist = 0; /* symbol table: linked list */

#include <u.h>
#include <libc.h>
#include "hoc.h"
#include "y.tab.h"

static Symbol *symlist = 0; /* symbol table: linked list */

Symbol*
lookup(char* s) /* find s in symbol table */
{
Symbol *sp;

for (sp = symlist; sp != (Symbol *) 0; sp = sp->next)
if (strcmp(sp->name, s) == 0)
return sp;
return 0; /* 0 ==> not found */
}

Symbol*
install(char* s, int t, double d) /* install s in symbol table */
{
Symbol *sp;

sp = emalloc(sizeof(Symbol));
sp->name = emalloc(strlen(s)+1); /* +1 for '\0' */
strcpy(sp->name, s);
sp->type = t;
sp->u.val = d;
sp->next = symlist; /* put at front of list */
symlist = sp;
return sp;
}

void*
emalloc(unsigned n) /* check return from malloc */
{
char *p;

p = malloc(n);
if (p == 0)
execerror("out of memory", (char *) 0);
return p;
}

Formal*
formallist(Symbol *formal, Formal *list) /* add formal to list */
{
Formal *f;

f = emalloc(sizeof(Formal));
f->sym = formal;
f->save = 0;
f->next = list;
return f;
}