Some formatting updates (ran the code through indent)
-Erik
This commit is contained in:
106
math.c
106
math.c
@ -1,3 +1,4 @@
|
||||
/* vi: set sw=4 ts=4: */
|
||||
#include "internal.h"
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
@ -8,126 +9,114 @@
|
||||
|
||||
static const char math_usage[] = "math expression ...";
|
||||
|
||||
static double stack[100];
|
||||
static unsigned int pointer;
|
||||
static double stack[100];
|
||||
static unsigned int pointer;
|
||||
|
||||
static void
|
||||
push(double a)
|
||||
static void push(double a)
|
||||
{
|
||||
if ( pointer >= (sizeof(stack) / sizeof(*stack)) ) {
|
||||
if (pointer >= (sizeof(stack) / sizeof(*stack))) {
|
||||
fprintf(stderr, "math: stack overflow\n");
|
||||
exit(-1);
|
||||
}
|
||||
else
|
||||
} else
|
||||
stack[pointer++] = a;
|
||||
}
|
||||
|
||||
static double
|
||||
pop()
|
||||
static double pop()
|
||||
{
|
||||
if ( pointer == 0 ) {
|
||||
if (pointer == 0) {
|
||||
fprintf(stderr, "math: stack underflow\n");
|
||||
exit(-1);
|
||||
}
|
||||
return stack[--pointer];
|
||||
}
|
||||
|
||||
static void
|
||||
add()
|
||||
static void add()
|
||||
{
|
||||
push(pop() + pop());
|
||||
}
|
||||
|
||||
static void
|
||||
sub()
|
||||
static void sub()
|
||||
{
|
||||
double subtrahend = pop();
|
||||
double subtrahend = pop();
|
||||
|
||||
push(pop() - subtrahend);
|
||||
}
|
||||
|
||||
static void
|
||||
mul()
|
||||
static void mul()
|
||||
{
|
||||
push(pop() * pop());
|
||||
}
|
||||
|
||||
static void
|
||||
divide()
|
||||
static void divide()
|
||||
{
|
||||
double divisor = pop();
|
||||
double divisor = pop();
|
||||
|
||||
push(pop() / divisor);
|
||||
}
|
||||
|
||||
static void
|
||||
and()
|
||||
static void and()
|
||||
{
|
||||
push((unsigned int)pop() & (unsigned int)pop());
|
||||
push((unsigned int) pop() & (unsigned int) pop());
|
||||
}
|
||||
|
||||
static void
|
||||
or()
|
||||
static void or()
|
||||
{
|
||||
push((unsigned int)pop() | (unsigned int)pop());
|
||||
push((unsigned int) pop() | (unsigned int) pop());
|
||||
}
|
||||
|
||||
static void
|
||||
eor()
|
||||
static void eor()
|
||||
{
|
||||
push((unsigned int)pop() ^ (unsigned int)pop());
|
||||
push((unsigned int) pop() ^ (unsigned int) pop());
|
||||
}
|
||||
|
||||
static void
|
||||
not()
|
||||
static void not()
|
||||
{
|
||||
push(~(unsigned int)pop());
|
||||
push(~(unsigned int) pop());
|
||||
}
|
||||
|
||||
static void
|
||||
print()
|
||||
static void print()
|
||||
{
|
||||
printf("%g\n", pop());
|
||||
}
|
||||
|
||||
struct op {
|
||||
const char * name;
|
||||
void (*function)();
|
||||
const char *name;
|
||||
void (*function) ();
|
||||
};
|
||||
|
||||
static const struct op operators[] = {
|
||||
{ "add", add },
|
||||
{ "and", and },
|
||||
{ "div", divide },
|
||||
{ "eor", eor },
|
||||
{ "mul", mul },
|
||||
{ "not", not },
|
||||
{ "or", or },
|
||||
{ "sub", sub },
|
||||
{ 0, 0 }
|
||||
static const struct op operators[] = {
|
||||
{"add", add},
|
||||
{"and", and},
|
||||
{"div", divide},
|
||||
{"eor", eor},
|
||||
{"mul", mul},
|
||||
{"not", not},
|
||||
{"or", or},
|
||||
{"sub", sub},
|
||||
{0, 0}
|
||||
};
|
||||
|
||||
static void
|
||||
stack_machine(const char * argument)
|
||||
static void stack_machine(const char *argument)
|
||||
{
|
||||
char * endPointer = 0;
|
||||
double d;
|
||||
const struct op * o = operators;
|
||||
char *endPointer = 0;
|
||||
double d;
|
||||
const struct op *o = operators;
|
||||
|
||||
if ( argument == 0 ) {
|
||||
if (argument == 0) {
|
||||
print();
|
||||
return;
|
||||
}
|
||||
|
||||
d = strtod(argument, &endPointer);
|
||||
|
||||
if ( endPointer != argument ) {
|
||||
if (endPointer != argument) {
|
||||
push(d);
|
||||
return;
|
||||
}
|
||||
|
||||
while ( o->name != 0 ) {
|
||||
if ( strcmp(o->name, argument) == 0 ) {
|
||||
(*(o->function))();
|
||||
while (o->name != 0) {
|
||||
if (strcmp(o->name, argument) == 0) {
|
||||
(*(o->function)) ();
|
||||
return;
|
||||
}
|
||||
o++;
|
||||
@ -136,10 +125,9 @@ stack_machine(const char * argument)
|
||||
exit(-1);
|
||||
}
|
||||
|
||||
int
|
||||
math_main(int argc, char * * argv)
|
||||
int math_main(int argc, char **argv)
|
||||
{
|
||||
while ( argc >= 2 ) {
|
||||
while (argc >= 2) {
|
||||
stack_machine(argv[1]);
|
||||
argv++;
|
||||
argc--;
|
||||
|
Reference in New Issue
Block a user