/* vi: set sw=4 ts=4: */
+/*
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "busybox.h"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <math.h>
-#include "busybox.h"
/* Tiny RPN calculator, because "expr" didn't give me bitwise operations. */
static double stack[100];
static unsigned int pointer;
+static unsigned char base;
static void push(double a)
{
if (pointer >= (sizeof(stack) / sizeof(*stack)))
- error_msg_and_die("stack overflow");
+ bb_error_msg_and_die("stack overflow");
stack[pointer++] = a;
}
static double pop(void)
{
if (pointer == 0)
- error_msg_and_die("stack underflow");
+ bb_error_msg_and_die("stack underflow");
return stack[--pointer];
}
push(pop() * pop());
}
+static void power(void)
+{
+ double topower = pop();
+
+ push(pow(pop(), topower));
+}
+
static void divide(void)
{
double divisor = pop();
push(pop() / divisor);
}
+static void mod(void)
+{
+ unsigned int d = pop();
+
+ push((unsigned int) pop() % d);
+}
+
static void and(void)
{
push((unsigned int) pop() & (unsigned int) pop());
push(~(unsigned int) pop());
}
-static void print(void)
+static void set_output_base(void)
{
- printf("%g\n", pop());
+ base=(unsigned char)pop();
+ if ((base != 10) && (base != 16)) {
+ fprintf(stderr, "Error: base = %d is not supported.\n", base);
+ base=10;
+ }
+}
+
+static void print_base(double print)
+{
+ if (base == 16)
+ printf("%x\n", (unsigned int)print);
+ else
+ printf("%g\n", print);
+}
+
+static void print_stack_no_pop(void)
+{
+ unsigned int i=pointer;
+ while (i)
+ print_base(stack[--i]);
+}
+
+static void print_no_pop(void)
+{
+ print_base(stack[pointer-1]);
}
struct op {
{"mul", mul},
{"/", divide},
{"div", divide},
+ {"**", power},
+ {"exp", power},
+ {"pow", power},
+ {"%", mod},
+ {"mod", mod},
{"and", and},
{"or", or},
{"not", not},
{"eor", eor},
+ {"xor", eor},
+ {"p", print_no_pop},
+ {"f", print_stack_no_pop},
+ {"o", set_output_base},
{0, 0}
};
double d;
const struct op *o = operators;
- if (argument == 0) {
- print();
+ if (argument == 0)
return;
- }
d = strtod(argument, &endPointer);
}
o++;
}
- error_msg_and_die("%s: syntax error.", argument);
+ bb_error_msg_and_die("%s: syntax error", argument);
}
/* return pointer to next token in buffer and set *buffer to one char
- * past the end of the above mentioned token
+ * past the end of the above mentioned token
*/
static char *get_token(char **buffer)
{
- char *start = NULL;
- char *current = *buffer;
+ char *start = NULL;
+ char *current;
- while (isspace(*current)) { current++; }
+ current = skip_whitespace(*buffer);
if (*current != 0) {
start = current;
- while (!isspace(*current) && current != 0) { current++; }
+ while (!isspace(*current) && *current != 0) { current++; }
*buffer = current;
}
return start;
char *line = NULL;
char *cursor = NULL;
char *token = NULL;
- while ((line = get_line_from_file(stdin))) {
+ while ((line = xmalloc_getline(stdin))) {
cursor = line;
len = number_of_tokens(line);
for (i = 0; i < len; i++) {
}
} else {
if (*argv[1]=='-')
- show_usage();
+ bb_show_usage();
while (argc >= 2) {
stack_machine(argv[1]);
argv++;
argc--;
}
}
- stack_machine(0);
return EXIT_SUCCESS;
}