mapnl option to window

[unix-history] / usr / src / usr.bin / window / parser3.c

#ifndef lint
static char sccsid[] = "@(#)parser3.c   3.3 %G%";
#endif

#include "parser.h"

/*
* =
* ? :
* ||
* &&
* |
* ^
* &
* == !=
* <= >=
* << >>
* + -
* * / %
* unary - + ~ !
*/
p_expr(v, flag)
register struct value *v;
char flag;
{
       struct value t;
       int ret;

       if (p_expr0(&t, flag) < 0)
               return -1;

       if (token != T_ASSIGN) {
               *v = t;
               return 0;
       }
       switch (t.v_type) {
       case V_NUM:
               p_error("%d: Not a variable.", t.v_num);
       case V_ERR:
               t.v_str = 0;
               break;
       }
       ret = p_assign(t.v_str, v, flag);
       if (t.v_str != 0)
               str_free(t.v_str);
       return ret;
}

/*
* ? :
*/
p_expr0(v, flag)
register struct value *v;
char flag;
{
       struct value t;
       char true;

       if (p_expr1(v, flag) < 0)
               return -1;
       if (token != T_QUEST)
               return 0;
       switch (v->v_type) {
       case V_NUM:
               true = v->v_num != 0;
               break;
       case V_STR:
               p_error("Numeric value required for ?.");
               str_free(v->v_str);
               v->v_type = V_ERR;
       case V_ERR:
               flag = 0;
               break;
       }
       (void) s_gettok();
       v->v_type = V_ERR;
       if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0)
               return -1;
       if (token != T_COLON) {
               val_free(*v);
               p_synerror();
               return -1;
       }
       (void) s_gettok();
       return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0);
}

/*
* ||
*/
p_expr1(v, flag)
register struct value *v;
char flag;
{
       char true = 0;

       if (p_expr2(v, flag) < 0)
               return -1;
       if (token != T_OROR)
               return 0;
       for (;;) {
               switch (v->v_type) {
               case V_NUM:
                       v->v_num = true = true || v->v_num != 0;
                       break;
               case V_STR:
                       p_error("Numeric value required for ||.");
                       str_free(v->v_str);
                       v->v_type = V_ERR;
               case V_ERR:
                       flag = 0;
                       break;
               }
               if (token != T_OROR)
                       return 0;
               (void) s_gettok();
               if (p_expr2(v, flag && !true) < 0)
                       return -1;
       }
}

/*
* &&
*/
p_expr2(v, flag)
register struct value *v;
char flag;
{
       char true = 1;

       if (p_expr3_10(3, v, flag) < 0)
               return -1;
       if (token != T_ANDAND)
               return 0;
       for (;;) {
               switch (v->v_type) {
               case V_NUM:
                       v->v_num = true = true && v->v_num != 0;
                       break;
               case V_STR:
                       p_error("Numeric value required for &&.");
                       str_free(v->v_str);
                       v->v_type = V_ERR;
               case V_ERR:
                       flag = 0;
                       break;
               }
               if (token != T_ANDAND)
                       return 0;
               (void) s_gettok();
               if (p_expr3_10(3, v, flag && true) < 0)
                       return -1;
       }
       /*NOTREACHED*/
}