diff -r 62f1a55535e7 -r 0b33b9396851 ucx/stack.h --- a/ucx/stack.h Mon Feb 04 14:46:11 2019 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,232 +0,0 @@ -/* - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. - * - * Copyright 2016 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. - */ - -/** - * @file stack.h - * - * Default stack memory allocation implementation. - * - * @author Mike Becker - * @author Olaf Wintermann - */ - -#ifndef UCX_STACK_H -#define UCX_STACK_H - -#include "ucx.h" -#include "allocator.h" - -#ifdef __cplusplus -extern "C" { -#endif - - -/** - * UCX stack structure. - */ -typedef struct { - /** UcxAllocator based on this stack */ - UcxAllocator allocator; - - /** Stack size. */ - size_t size; - - /** Pointer to the bottom of the stack */ - char *space; - - /** Pointer to the top of the stack */ - char *top; -} UcxStack; - -/** - * Metadata for each UCX stack element. - */ -struct ucx_stack_metadata { - /** - * Location of the previous element (NULL if this is the first) - */ - char *prev; - - /** Size of this element */ - size_t size; -}; - -/** - * Initializes UcxStack structure with memory. - * - * @param stack a pointer to an uninitialized stack structure - * @param space the memory area that shall be managed - * @param size size of the memory area - * @return a new UcxStack structure - */ -void ucx_stack_init(UcxStack *stack, char* space, size_t size); - -/** - * Allocates stack memory. - * - * @param stack a pointer to the stack - * @param n amount of memory to allocate - * @return a pointer to the allocated memory - * @see ucx_allocator_malloc() - */ -void *ucx_stack_malloc(UcxStack *stack, size_t n); - -/** - * Alias for #ucx_stack_malloc(). - * @param stack a pointer to the stack - * @param n amount of memory to allocate - * @return a pointer to the allocated memory - * @see ucx_stack_malloc - */ -#define ucx_stack_push(stack, n) ucx_stack_malloc(stack, n) - -/** - * Allocates an array of stack memory - * - * The content of the allocated memory is set to zero. - * - * @param stack a pointer to the stack - * @param nelem amount of elements to allocate - * @param elsize amount of memory per element - * @return a pointer to the allocated memory - * @see ucx_allocator_calloc() - */ -void *ucx_stack_calloc(UcxStack *stack, size_t nelem, size_t elsize); - -/** - * Alias for #ucx_stack_calloc(). - * - * @param stack a pointer to the stack - * @param n amount of elements to allocate - * @param elsize amount of memory per element - * @return a pointer to the allocated memory - * @see ucx_stack_calloc - */ -#define ucx_stack_pusharr(stack,n,elsize) ucx_stack_calloc(stack,n,elssize) - -/** - * Reallocates memory on the stack. - * - * Shrinking memory is always safe. Extending memory can be very expensive. - * - * @param stack the stack - * @param ptr a pointer to the memory that shall be reallocated - * @param n the new size of the memory - * @return a pointer to the new location of the memory - * @see ucx_allocator_realloc() - */ -void *ucx_stack_realloc(UcxStack *stack, void *ptr, size_t n); - -/** - * Frees memory on the stack. - * - * Freeing stack memory behaves in a special way. - * - * If the element, that should be freed, is the top most element of the stack, - * it is removed from the stack. Otherwise it is marked as freed. Marked - * elements are removed, when they become the top most elements of the stack. - * - * @param stack a pointer to the stack - * @param ptr a pointer to the memory that shall be freed - */ -void ucx_stack_free(UcxStack *stack, void *ptr); - - -/** - * Returns the size of the top most element. - * @param stack a pointer to the stack - * @return the size of the top most element - */ -#define ucx_stack_topsize(stack) ((stack)->top ? ((struct ucx_stack_metadata*)\ - (stack)->top - 1)->size : 0) - -/** - * Removes the top most element from the stack and copies the content to - * dest, if specified. - * - * Use #ucx_stack_topsize()# to get the amount of memory that must be available - * at the location of dest. - * - * @param stack a pointer to the stack - * @param dest the location where the contents shall be written to, or - * NULL, if the element shall only be removed. - * @see ucx_stack_free - * @see ucx_stack_popn - */ -#define ucx_stack_pop(stack, dest) ucx_stack_popn(stack, dest, (size_t)-1) - -/** - * Removes the top most element from the stack and copies the content to - * dest. - * - * In contrast to #ucx_stack_pop() the dest pointer MUST - * NOT be NULL. - * - * @param stack a pointer to the stack - * @param dest the location where the contents shall be written to - * @param n copies at most n elements to dest - * @see ucx_stack_pop - */ -void ucx_stack_popn(UcxStack *stack, void *dest, size_t n); - -/** - * Returns the remaining available memory on the specified stack. - * - * @param stack a pointer to the stack - * @return the remaining available memory - */ -size_t ucx_stack_avail(UcxStack *stack); - -/** - * Checks, if the stack is empty. - * - * @param stack a pointer to the stack - * @return nonzero, if the stack is empty, zero otherwise - */ -#define ucx_stack_empty(stack) (!(stack)->top) - -/** - * Computes a recommended size for the stack memory area. Note, that - * reallocations have not been taken into account, so you might need to reserve - * twice as much memory to allow many reallocations. - * - * @param size the approximate payload - * @param elems the approximate count of element allocations - * @return a recommended size for the stack space based on the information - * provided - */ -#define ucx_stack_dim(size, elems) (size+sizeof(struct ucx_stack_metadata) * \ - (elems + 1)) - - -#ifdef __cplusplus -} -#endif - -#endif /* UCX_STACK_H */ -