-/*
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
- *
- * Copyright 2017 Mike Becker, Olaf Wintermann All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "ucx/stack.h"
-
-#include <string.h>
-
-static size_t ucx_stack_align(size_t n) {
- int align = n % sizeof(void*);
- if (align) {
- n += sizeof(void*) - align;
- }
- return n;
-}
-
-void ucx_stack_init(UcxStack *stack, char* space, size_t size) {
- stack->size = size - size % sizeof(void*);
- stack->space = space;
- stack->top = NULL;
-
- stack->allocator.pool = stack;
- stack->allocator.malloc = (ucx_allocator_malloc) ucx_stack_malloc;
- stack->allocator.calloc = (ucx_allocator_calloc) ucx_stack_calloc;
- stack->allocator.realloc = (ucx_allocator_realloc) ucx_stack_realloc;
- stack->allocator.free = (ucx_allocator_free) ucx_stack_free;
-}
-
-void *ucx_stack_malloc(UcxStack *stack, size_t n) {
-
- if (ucx_stack_avail(stack) < ucx_stack_align(n)) {
- return NULL;
- } else {
- char *prev = stack->top;
- if (stack->top) {
- stack->top += ucx_stack_align(ucx_stack_topsize(stack));
- } else {
- stack->top = stack->space;
- }
-
- ((struct ucx_stack_metadata*)stack->top)->prev = prev;
- ((struct ucx_stack_metadata*)stack->top)->size = n;
- stack->top += sizeof(struct ucx_stack_metadata);
-
- return stack->top;
- }
-}
-
-void *ucx_stack_calloc(UcxStack *stack, size_t nelem, size_t elsize) {
- void *mem = ucx_stack_malloc(stack, nelem*elsize);
- memset(mem, 0, nelem*elsize);
- return mem;
-}
-
-void *ucx_stack_realloc(UcxStack *stack, void *ptr, size_t n) {
- if (ptr == stack->top) {
- if (stack->size - (stack->top - stack->space) < ucx_stack_align(n)) {
- return NULL;
- } else {
- ((struct ucx_stack_metadata*)stack->top - 1)->size = n;
- return ptr;
- }
- } else {
- if (ucx_stack_align(((struct ucx_stack_metadata*)ptr - 1)->size) <
- ucx_stack_align(n)) {
- void *nptr = ucx_stack_malloc(stack, n);
- if (nptr) {
- memcpy(nptr, ptr, n);
- ucx_stack_free(stack, ptr);
-
- return nptr;
- } else {
- return NULL;
- }
- } else {
- ((struct ucx_stack_metadata*)ptr - 1)->size = n;
- return ptr;
- }
- }
-}
-
-void ucx_stack_free(UcxStack *stack, void *ptr) {
- if (ptr == stack->top) {
- stack->top = ((struct ucx_stack_metadata*) stack->top - 1)->prev;
- } else {
- struct ucx_stack_metadata *next = (struct ucx_stack_metadata*)(
- (char*)ptr +
- ucx_stack_align(((struct ucx_stack_metadata*) ptr - 1)->size)
- );
- next->prev = ((struct ucx_stack_metadata*) ptr - 1)->prev;
- }
-}
-
-void ucx_stack_popn(UcxStack *stack, void *dest, size_t n) {
- if (ucx_stack_empty(stack)) {
- return;
- }
-
- if (dest) {
- size_t len = ucx_stack_topsize(stack);
- if (len > n) {
- len = n;
- }
-
- memcpy(dest, stack->top, len);
- }
-
- ucx_stack_free(stack, stack->top);
-}
-
-size_t ucx_stack_avail(UcxStack *stack) {
- size_t avail = ((stack->top ? (stack->size
- - (stack->top - stack->space)
- - ucx_stack_align(ucx_stack_topsize(stack)))
- : stack->size));
-
- if (avail > sizeof(struct ucx_stack_metadata)) {
- return avail - sizeof(struct ucx_stack_metadata);
- } else {
- return 0;
- }
-}
-
-void *ucx_stack_push(UcxStack *stack, size_t n, const void *data) {
- void *space = ucx_stack_malloc(stack, n);
- if (space) {
- memcpy(space, data, n);
- }
- return space;
-}
-
-void *ucx_stack_pusharr(UcxStack *stack,
- size_t nelem, size_t elsize, const void *data) {
-
- // skip the memset by using malloc
- void *space = ucx_stack_malloc(stack, nelem*elsize);
- if (space) {
- memcpy(space, data, nelem*elsize);
- }
- return space;
-}