ucx: ucx/stack.c@b7d1317b138e (annotated)

ucx/stack.c@b7d1317b138e (annotated)

ucx/stack.c

Tue, 17 Oct 2017 15:15:54 +0200

author: Mike Becker <universe@uap-core.de>
date: Tue, 17 Oct 2017 15:15:54 +0200
changeset 250: b7d1317b138e
parent 225: a1a068c2c4ef
permissions: -rw-r--r--

updates license

 /*
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
  *
  * Copyright 2017 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 "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;
     }
     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;
     }
 }

Mercurial > hg > ucx / annotate

ucx/stack.c@b7d1317b138e (annotated)

ucx/stack.c