stack.c

typedef struct stack_s
{
    long sz;
    long sp;
    void **s;
} *stack_t;

#define stack_pop(__t,__s) ((__t)_stack_pop(__s))
#define stack_peek(__t,__s) ((__t)_stack_peek(__s))
#define stack_is_empty(_s) (_s->sp == -1)
#define stack_not_empty(_s) (_s->sp != -1)
#define STACK_DEFAULT_RESIZE 1024

static inline stack_t stack_new();
static inline stack_t stack_dup(const stack_t s);
static inline stack_t stack_clone(const stack_t s, void *(*clone_entry)(void *));

static inline void stack_free(stack_t s);
static inline void stack_push(stack_t s, void *item);
static inline void *_stack_pop(stack_t s);
static inline void *_stack_peek(stack_t s);


static inline stack_t stack_new()
{
    stack_t ret = malloc(sizeof *ret);
    ASSERT(ret != NULL);
    memset(ret, 0, sizeof(*ret));
    ret->sp = -1;
    return ret;
}

static inline stack_t stack_dup(const stack_t s)
{
    stack_t ret = stack_new();
    ret->s = malloc(s->sz * sizeof(void*));
    memcpy(ret->s, s->s, s->sz * sizeof(void*));
    ret->sp = s->sp;
    ret->sz = s->sz;
    return ret;
}

static inline stack_t stack_clone(const stack_t s, void *(*clone_entry)(void *))
{
    stack_t ret = stack_new();
    ret->s = malloc(s->sz * sizeof(void *));
    ret->sp = s->sp;
    ret->sz = s->sz;
    for (long i = 0; i <= s->sp; i++)
        ret->s[i] = clone_entry(s->s[i]);
    return ret;
}

static inline void stack_push(stack_t s, void *item)
{
    ASSERT(s != NULL);
    s->sp += 1;
    if (s->sz <= s->sp)
    {
        s->sz += STACK_DEFAULT_RESIZE;
        s->s = (void **)realloc(s->s, s->sz * sizeof(void *));
    }
    s->s[s->sp] = item;
}

static inline void stack_free(stack_t s)
{
    ASSERT(s != NULL);
    if (s->s) free(s->s);
    free(s);
}

static inline void *_stack_pop(stack_t s)
{
    if (s->sp == -1) return NULL;
    return s->s[s->sp--];
}

static inline void *_stack_peek(stack_t s)
{
    if (s->sp == -1) return NULL;
    return s->s[s->sp];
}