/* $OpenBSD: stack.c,v 1.13 2014/12/01 13:13:00 deraadt Exp $ */
/*
* Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/cdefs.h>
#include <err.h>
#include <stdlib.h>
#include <string.h>
#include "extern.h"
static __inline bool stack_empty(const struct stack *);
static void stack_grow(struct stack *);
static struct array *array_new(void);
static __inline void array_free(struct array *);
static struct array *array_dup(const struct array *);
static __inline void array_grow(struct array *, size_t);
static __inline void array_assign(struct array *, size_t, const struct value *);
static __inline struct value *array_retrieve(const struct array *, size_t);
void
stack_init(struct stack *stack)
{
stack->size = 0;
stack->sp = -1;
stack->stack = NULL;
}
static __inline bool
stack_empty(const struct stack *stack)
{
bool empty = stack->sp == -1;
if (empty)
warnx("stack empty");
return empty;
}
/* Clear number or string, but leave value itself */
void
stack_free_value(struct value *v)
{
switch (v->type) {
case BCODE_NONE:
break;
case BCODE_NUMBER:
free_number(v->u.num);
break;
case BCODE_STRING:
free(v->u.string);
break;
}
array_free(v->array);
v->array = NULL;
}
/* Copy number or string content into already allocated target */
struct value *
stack_dup_value(const struct value *a, struct value *copy)
{
copy->type = a->type;
switch (a->type) {
case BCODE_NONE:
break;
case BCODE_NUMBER:
copy->u.num = dup_number(a->u.num);
break;
case BCODE_STRING:
copy->u.string = strdup(a->u.string);
if (copy->u.string == NULL)
err(1, NULL);
break;
}
copy->array = a->array == NULL ? NULL : array_dup(a->array);
return (copy);
}
size_t
stack_size(const struct stack *stack)
{
return (stack->sp + 1);
}
void
stack_dup(struct stack *stack)
{
struct value *value;
struct value copy;
value = stack_tos(stack);
if (value == NULL) {
warnx("stack empty");
return;
}
stack_push(stack, stack_dup_value(value, ©));
}
void
stack_swap(struct stack *stack)
{
struct value copy;
if (stack->sp < 1) {
warnx("stack empty");
return;
}
copy = stack->stack[stack->sp];
stack->stack[stack->sp] = stack->stack[stack->sp-1];
stack->stack[stack->sp-1] = copy;
}
static void
stack_grow(struct stack *stack)
{
size_t new_size;
if (++stack->sp == stack->size) {
new_size = stack->size * 2 + 1;
stack->stack = breallocarray(stack->stack,
new_size, sizeof(*stack->stack));
stack->size = new_size;
}
}
void
stack_pushnumber(struct stack *stack, struct number *b)
{
stack_grow(stack);
stack->stack[stack->sp].type = BCODE_NUMBER;
stack->stack[stack->sp].u.num = b;
stack->stack[stack->sp].array = NULL;
}
void
stack_pushstring(struct stack *stack, char *string)
{
stack_grow(stack);
stack->stack[stack->sp].type = BCODE_STRING;
stack->stack[stack->sp].u.string = string;
stack->stack[stack->sp].array = NULL;
}
void
stack_push(struct stack *stack, struct value *v)
{
switch (v->type) {
case BCODE_NONE:
stack_grow(stack);
stack->stack[stack->sp].type = BCODE_NONE;
break;
case BCODE_NUMBER:
stack_pushnumber(stack, v->u.num);
break;
case BCODE_STRING:
stack_pushstring(stack, v->u.string);
break;
}
stack->stack[stack->sp].array = v->array == NULL ?
NULL : array_dup(v->array);
}
struct value *
stack_tos(const struct stack *stack)
{
if (stack->sp == -1)
return (NULL);
return &stack->stack[stack->sp];
}
void
stack_set_tos(struct stack *stack, struct value *v)
{
if (stack->sp == -1)
stack_push(stack, v);
else {
stack_free_value(&stack->stack[stack->sp]);
stack->stack[stack->sp] = *v;
stack->stack[stack->sp].array = v->array == NULL ?
NULL : array_dup(v->array);
}
}
struct value *
stack_pop(struct stack *stack)
{
if (stack_empty(stack))
return (NULL);
return &stack->stack[stack->sp--];
}
struct number *
stack_popnumber(struct stack *stack)
{
if (stack_empty(stack))
return (NULL);
array_free(stack->stack[stack->sp].array);
stack->stack[stack->sp].array = NULL;
if (stack->stack[stack->sp].type != BCODE_NUMBER) {
warnx("not a number"); /* XXX remove */
return (NULL);
}
return stack->stack[stack->sp--].u.num;
}
char *
stack_popstring(struct stack *stack)
{
if (stack_empty(stack))
return (NULL);
array_free(stack->stack[stack->sp].array);
stack->stack[stack->sp].array = NULL;
if (stack->stack[stack->sp].type != BCODE_STRING) {
warnx("not a string"); /* XXX remove */
return (NULL);
}
return stack->stack[stack->sp--].u.string;
}
void
stack_clear(struct stack *stack)
{
while (stack->sp >= 0)
stack_free_value(&stack->stack[stack->sp--]);
free(stack->stack);
stack_init(stack);
}
void
stack_print(FILE *f, const struct stack *stack, const char *prefix, u_int base)
{
ssize_t i;
for (i = stack->sp; i >= 0; i--) {
print_value(f, &stack->stack[i], prefix, base);
putc('\n', f);
}
}
static struct array *
array_new(void)
{
struct array *a;
a = bmalloc(sizeof(*a));
a->data = NULL;
a->size = 0;
return a;
}
static __inline void
array_free(struct array *a)
{
size_t i;
if (a == NULL)
return;
for (i = 0; i < a->size; i++)
stack_free_value(&a->data[i]);
free(a->data);
free(a);
}
static struct array *
array_dup(const struct array *a)
{
struct array *n;
size_t i;
if (a == NULL)
return (NULL);
n = array_new();
array_grow(n, a->size);
for (i = 0; i < a->size; i++)
stack_dup_value(&a->data[i], &n->data[i]);
return (n);
}
static __inline void
array_grow(struct array *array, size_t newsize)
{
size_t i;
array->data = breallocarray(array->data, newsize, sizeof(*array->data));
for (i = array->size; i < newsize; i++) {
array->data[i].type = BCODE_NONE;
array->data[i].array = NULL;
}
array->size = newsize;
}
static __inline void
array_assign(struct array *array, size_t i, const struct value *v)
{
if (i >= array->size)
array_grow(array, i + 1);
stack_free_value(&array->data[i]);
array->data[i] = *v;
}
static __inline struct value *
array_retrieve(const struct array *array, size_t i)
{
if (i >= array->size)
return (NULL);
return &array->data[i];
}
void
frame_assign(struct stack *stack, size_t i, const struct value *v)
{
struct array *a;
struct value n;
if (stack->sp == -1) {
n.type = BCODE_NONE;
n.array = NULL;
stack_push(stack, &n);
}
a = stack->stack[stack->sp].array;
if (a == NULL)
a = stack->stack[stack->sp].array = array_new();
array_assign(a, i, v);
}
struct value *
frame_retrieve(const struct stack *stack, size_t i)
{
struct array *a;
if (stack->sp == -1)
return (NULL);
a = stack->stack[stack->sp].array;
if (a == NULL)
a = stack->stack[stack->sp].array = array_new();
return array_retrieve(a, i);
}
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