jehanne/sys/src/cmd/hoc/symbol.c

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/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <lib9.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;
}