olaf@13: /*
universe@103:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
olaf@13:  *
universe@177:  * Copyright 2014 Olaf Wintermann. All rights reserved.
universe@103:  *
universe@103:  * Redistribution and use in source and binary forms, with or without
universe@103:  * modification, are permitted provided that the following conditions are met:
universe@103:  *
universe@103:  *   1. Redistributions of source code must retain the above copyright
universe@103:  *      notice, this list of conditions and the following disclaimer.
universe@103:  *
universe@103:  *   2. Redistributions in binary form must reproduce the above copyright
universe@103:  *      notice, this list of conditions and the following disclaimer in the
universe@103:  *      documentation and/or other materials provided with the distribution.
universe@103:  *
universe@103:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@103:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@103:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@103:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@103:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@103:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@103:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@103:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@103:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@103:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@103:  * POSSIBILITY OF SUCH DAMAGE.
olaf@13:  */
olaf@13: 
universe@182: #include "stack.h"
olaf@13: #include <string.h>
olaf@13: 
universe@182: UcxStack ucx_stack_new(char* space, size_t size) {
universe@182:     UcxStack stack;
universe@182:     stack.size = size;
universe@182:     stack.space = stack.top = space;
universe@182:     
universe@182:     UcxAllocator alloc;
universe@182:     alloc.pool = &stack;
universe@182:     alloc.malloc = (ucx_allocator_malloc) ucx_stack_malloc;
universe@182:     alloc.calloc = (ucx_allocator_calloc) ucx_stack_calloc;
universe@182:     alloc.realloc = (ucx_allocator_realloc) ucx_stack_realloc;
universe@182:     alloc.free = (ucx_allocator_free) ucx_stack_free;
universe@182:     
universe@182:     stack.allocator = alloc;
universe@182:     
universe@182:     return stack;
olaf@13: }
olaf@13: 
universe@182: void *ucx_stack_malloc(UcxStack *stack, size_t n) {
universe@182:     n += n % sizeof(void*);
universe@182: 
universe@182:     if (stack->top + n + sizeof(size_t) > stack->space + stack->size) {
universe@135:         return NULL;
universe@135:     } else {
universe@182:         void *ptr = stack->top;
universe@182:         
universe@182:         *((size_t*) (stack->top + n)) = n;
universe@182:         stack->top += n + sizeof(size_t);
universe@182:         
universe@182:         return ptr;
universe@15:     }
olaf@13: }
olaf@13: 
universe@182: void *ucx_stack_calloc(UcxStack *stack, size_t nelem, size_t elsize) {
universe@182:     void *mem = ucx_stack_malloc(stack, nelem*elsize);
universe@182:     memset(mem, 0, nelem*elsize);
universe@182:     return mem;
olaf@13: }
olaf@13: 
universe@182: void *ucx_stack_realloc(UcxStack *stack, void *ptr, size_t n) {
universe@182:     if (ptr == stack->top - sizeof(size_t) - *((size_t*) stack->top - 1)) {
olaf@13: 
universe@182:         stack->top = (char*)ptr + n;
universe@182:         *((size_t*)stack->top) = n;
universe@182:         stack->top += sizeof(size_t);
universe@182:         
universe@182:         return ptr;
universe@182:     } else {
universe@182:         size_t* sptr = (size_t*) (((char*) ptr)-sizeof(size_t));
universe@182:         if (*sptr < n) {
universe@182:             void *nptr = ucx_stack_malloc(stack, n);
universe@182:             if (nptr) {
universe@182:                 memcpy(nptr, ptr, *sptr);
universe@182:                 ucx_stack_free(stack, ptr);
universe@182:                 return nptr;
universe@182:             } else {
universe@182:                 return NULL;
olaf@14:             }
universe@182:         } else {
universe@182:             *sptr = n;
universe@182:             return ptr;
olaf@13:         }
olaf@13:     }
olaf@13: }
olaf@13: 
universe@182: void ucx_stack_free(UcxStack *stack, void *ptr) {
universe@182:     if (ptr == stack->top+sizeof(size_t)) {
universe@182:         
universe@182:     } else {
universe@182:         
olaf@113:     }
olaf@113: }
olaf@113: 
universe@182: void ucx_stack_pop(UcxStack *stack, void *dest) {
olaf@13: }
olaf@13: 
universe@182: void ucx_stack_popn(UcxStack *stack, void *dest, size_t n) {
olaf@13: }