static int opr_handler(struct calc *calc)
{
assert(calc != NULL);
char c = *calc->cur;
opr_advance(calc);
/* 如果操作符栈是空栈的话就压栈 */
if (STACK_IS_EMPTY(calc->opr)) {
OPR_PUSH(c);
return 0;
}
/* 如果操作符栈非空， 且该操作符优先级高于栈顶运算符就压栈 */
char top_c = 0;
if (OPR_TOP(top_c) < 0) {
fprintf(stderr, "Error: opr top failed.\n");
return -1;
}
while(1) {
if (opr2level(c) > opr2level(top_c) || STACK_IS_EMPTY(calc->opr)) {
OPR_PUSH(c);
return 0;
}
if (do_operate(calc) < 0) {
fprintf(stderr, "Error: do operate failed.\n");
return -1;
}
if ( !STACK_IS_EMPTY(calc->opr) && OPR_TOP(top_c) < 0) {
fprintf(stderr, "Error: while opr top failed.\n");
return -1;
}
}
return 0;
}
static int opr_handle(struct calc_info *info)
{
assert(info != NULL);
char c = *info->cur;
if (info->flag == NUM) {
info->flag = OPR;
} else {
switch (c) {
case '+':
goto out;
break;
case '-':
//FIXME 负号的处理
{
num_t zero = 0;
NUM_PUSH(zero);
OPR_PUSH(c);
goto out;
}
break;
default:
fprintf(stderr, "免费版不支持多个运算符\n");
break;
}
}
//1. 入栈的两种情况： a) 空栈 b）运算符优先级高于栈顶运算符
if (OPR_IS_EMPTY) {
OPR_PUSH(c);
} else {
char top_c;
while (1) {
//a 空栈
if (OPR_TOP(top_c) < 0) {
OPR_PUSH(c);
break;
}
//b 优先级高于栈顶
if (opr2level(c) > opr2level(top_c)) {
OPR_PUSH(c);
break;
} else {
if (do_stack(info) < 0) {
fprintf(stderr,"do_stack failed\n");
goto err_do_stack;
}
}
}
}
out:
return 0;
err_do_stack:
return -1;
}
static int opr_handler(struct calc *calc)
{
assert(calc != NULL);
char c = *calc->cur;
int zero = 0;
if (calc->pre_flag == F_NUM) {
calc->pre_flag = F_OPR;
} else if (calc->pre_flag == F_OPR) {
if (c == '-') {
NUM_PUSH(zero);
OPR_PUSH(c);
calc->pre_flag = F_OPR;
return 0;
} else if (c == '+') {
return 0;
}
} else {
fprintf(stderr, "unknow character\n");
return -2;
}
/* 如果操作符栈是空栈的话就压栈 */
if (STACK_IS_EMPTY(calc->opr)) {
OPR_PUSH(c);
return 0;
}
/* 如果操作符栈非空， 且该操作符优先级高于栈顶运算符就压栈 */
char top_c = 0;
if (OPR_TOP(top_c) < 0) {
fprintf(stderr, "Error: opr top failed.\n");
return -1;
}
while(1) {
if (opr2level(c) > opr2level(top_c) || STACK_IS_EMPTY(calc->opr)) {
OPR_PUSH(c);
return 0;
}
if (do_operate(calc) < 0) {
fprintf(stderr, "Error: do operate failed.\n");
return -1;
}
if ( !STACK_IS_EMPTY(calc->opr) && OPR_TOP(top_c) < 0) {
fprintf(stderr, "Error: while opr top failed.\n");
return -1;
}
}
return 0;
}
