da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/***********************************************************************
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* This software is part of the ast package *
3e14f97f673e8a630f076077de35afdd43dc1587Roger A. Faulkner* Copyright (c) 1985-2010 AT&T Intellectual Property *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* and is licensed under the *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Common Public License, Version 1.0 *
7c2fbfb345896881c631598ee3852ce9ce33fb07April Chin* by AT&T Intellectual Property *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* A copy of the License is available at *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* http://www.opensource.org/licenses/cpl1.0.txt *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Information and Software Systems Research *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* AT&T Research *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Florham Park NJ *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Glenn Fowler <gsf@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* David Korn <dgk@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Phong Vo <kpv@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin***********************************************************************/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#pragma prototyped
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/*
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * G. S. Fowler
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * D. G. Korn
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * AT&T Bell Laboratories
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * long integer arithmetic expression evaluator
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * long constants may be represented as:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * 0ooo octal
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * 0[xX]hhh hexadecimal
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * ddd decimal
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * n#ccc base n, 2 <= b <= 36
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * NOTE: all operands are evaluated as both the parse
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * and evaluation are done on the fly
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#include <ast.h>
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#include <ctype.h>
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#define getchr(ex) (*(ex)->nextchr++)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#define peekchr(ex) (*(ex)->nextchr)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#define ungetchr(ex) ((ex)->nextchr--)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin#define error(ex,msg) return(seterror(ex,msg))
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chintypedef struct /* expression handle */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin{
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin char* nextchr; /* next expression char */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin char* errchr; /* next char after error */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin char* errmsg; /* error message text */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin long (*convert)(const char*, char**, void*);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin void* handle; /* user convert handle */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin} Expr_t;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/*
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * set error message string
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinstatic long
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinseterror(register Expr_t* ex, char* msg)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin{
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!ex->errmsg) ex->errmsg = msg;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex->errchr = ex->nextchr;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex->nextchr = "";
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin return(0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin}
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/*
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * evaluate a subexpression with precedence
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinstatic long
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinexpr(register Expr_t* ex, register int precedence)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin{
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register int c;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register long n;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register long x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin char* pos;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin int operand = 1;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin while (c = getchr(ex), isspace(c));
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin switch (c)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case 0:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ungetchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!precedence) return(0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin error(ex, "more tokens expected");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '-':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = -expr(ex, 13);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '+':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = expr(ex, 13);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '!':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = !expr(ex, 13);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '~':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = ~expr(ex, 13);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin default:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ungetchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin operand = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin for (;;)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin switch (c = getchr(ex))
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case 0:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case ')':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!precedence) error(ex, "too many )'s");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '(':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = expr(ex, 1);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (getchr(ex) != ')')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ungetchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin error(ex, "closing ) expected");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin gotoperand:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (operand) error(ex, "operator expected");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin operand = 1;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin continue;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '?':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 1) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) == ':')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 2);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!n) n = x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 2);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (getchr(ex) != ':')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ungetchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin error(ex, ": expected for ? operator");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (n)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin expr(ex, 2);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n = expr(ex, 2);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case ':':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '|':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) == '|')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 2) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 3);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = n || x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 4) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 5);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n |= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '^':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 5) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 6);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n ^= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '&':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) == '&')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 3) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 4);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = n && x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 6) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 7);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n &= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '=':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '!':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) != '=') error(ex, "operator syntax error");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 7) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 8);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '=') n = n == x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n = n != x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '<':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '>':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) == c)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 9) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 10);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '<') n <<= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n >>= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 8) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(ex) == '=')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin getchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 9);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '<') n = n <= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n = n >= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 9);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '<') n = n < x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n = n > x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '+':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '-':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 10) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 11);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '+') n += x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n -= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '*':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '/':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin case '%':
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (precedence > 11) goto done;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin x = expr(ex, 12);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (c == '*') n *= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else if (x == 0) error(ex, "divide by zero");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else if (c == '/') n /= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else n %= x;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin break;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin default:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (isspace(c)) continue;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin pos = --ex->nextchr;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (isdigit(c)) n = strton(ex->nextchr, &ex->nextchr, NiL, 0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin else if (ex->convert) n = (*ex->convert)(ex->nextchr, &ex->nextchr, ex->handle);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (ex->nextchr == pos) error(ex, "syntax error");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin goto gotoperand;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (ex->errmsg) return(0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!operand) error(ex, "operand expected");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin done:
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ungetchr(ex);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!operand) error(ex, "operand expected");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin return(n);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin}
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/*
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * evaluate an integer arithmetic expression in s
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * (long)(*convert)(const char* string, char** end, void* handle)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * is a user supplied conversion routine that is called when unknown
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * chars are encountered; string points to the part to be
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * converted and end is adjusted to point to the next non-converted
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * character; if string is 0 then end points to an error message string
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * NOTE: (*convert)() may call strexpr(ex, )
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin */
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinlong
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chinstrexpr(const char* s, char** end, long(*convert)(const char*, char**, void*), void* handle)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin{
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin long n;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin Expr_t ex;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex.nextchr = (char*)s;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex.errmsg = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex.convert = convert;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex.handle = handle;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = expr(&ex, 0);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (peekchr(&ex) == ':')
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin seterror(&ex, "invalid use of :");
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (ex.errmsg)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin {
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (convert) (*convert)(NiL, &ex.errmsg, handle);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin ex.nextchr = ex.errchr;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin n = 0;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin }
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (end) *end = ex.nextchr;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin return(n);
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin}