/* * Simple pointer stack * * (c) 2010 Arnaldo Carvalho de Melo <acme@redhat.com> */ #include "util.h"#include "pstack.h"#include <linux/kernel.h>#include <stdlib.h> struct pstack {	unsigned short	top;	unsigned short	max_nr_entries;	void		*entries[0];}; struct pstack *pstack__new(unsigned short max_nr_entries){	struct pstack *self = zalloc((sizeof(*self) +				     max_nr_entries * sizeof(void *)));	if (self != NULL)		self->max_nr_entries = max_nr_entries;	return self;} void pstack__delete(struct pstack *self){	free(self);} bool pstack__empty(const struct pstack *self){	return self->top == 0;} void pstack__remove(struct pstack *self, void *key){	unsigned short i = self->top, last_index = self->top - 1; 	while (i-- != 0) {		if (self->entries[i] == key) {			if (i < last_index)				memmove(self->entries + i,					self->entries + i + 1,					(last_index - i) * sizeof(void *));			--self->top;			return;		}	}	pr_err("%s: %p not on the pstack!\n", __func__, key);} void pstack__push(struct pstack *self, void *key){	if (self->top == self->max_nr_entries) {		pr_err("%s: top=%d, overflow!\n", __func__, self->top);		return;	}	self->entries[self->top++] = key;} void *pstack__pop(struct pstack *self){	void *ret; 	if (self->top == 0) {		pr_err("%s: underflow!\n", __func__);		return NULL;	} 	ret = self->entries[--self->top];	self->entries[self->top] = NULL;	return ret;}