universe@571: /*
universe@571:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@571:  *
universe@571:  * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
universe@571:  *
universe@571:  * Redistribution and use in source and binary forms, with or without
universe@571:  * modification, are permitted provided that the following conditions are met:
universe@571:  *
universe@571:  *   1. Redistributions of source code must retain the above copyright
universe@571:  *      notice, this list of conditions and the following disclaimer.
universe@571:  *
universe@571:  *   2. Redistributions in binary form must reproduce the above copyright
universe@571:  *      notice, this list of conditions and the following disclaimer in the
universe@571:  *      documentation and/or other materials provided with the distribution.
universe@571:  *
universe@571:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@571:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@571:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@571:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@571:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@571:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@571:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@571:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@571:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@571:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@571:  * POSSIBILITY OF SUCH DAMAGE.
universe@571:  */
universe@571: 
universe@571: #include "cx/basic_mempool.h"
universe@571: #include "cx/utils.h"
universe@571: #include <string.h>
universe@571: 
universe@571: #define of_chk_(n) if (SIZE_MAX - sizeof(cx_destructor_func) < (n)) return NULL
universe@571: 
universe@571: /** Internal structure for denoting pooled memory. */
universe@571: typedef struct {
universe@571:     /** The destructor. */
universe@571:     cx_destructor_func destructor;
universe@571:     /**
universe@571:      * Access to the first byte of the polled memory.
universe@571:      */
universe@571:     char c;
universe@571: } cx_basic_mempool_memory;
universe@571: 
universe@571: static int cx_basic_mempool_chcap(
universe@571:         struct cx_basic_mempool_s *pool,
universe@571:         size_t newcap
universe@571: ) {
universe@571:     if (newcap < pool->ndata) {
universe@571:         return 1;
universe@571:     }
universe@571: 
universe@571:     size_t newcapsz;
universe@571:     if (cx_szmul(newcap, sizeof(void *), &newcapsz)) {
universe@571:         return 1;
universe@571:     }
universe@571: 
universe@571:     void **data = realloc(pool->data, newcapsz);
universe@571:     if (data) {
universe@571:         pool->data = data;
universe@571:         pool->size = newcap;
universe@571:         return 0;
universe@571:     } else {
universe@571:         return 1;
universe@571:     }
universe@571: }
universe@571: 
universe@571: void *cx_malloc_basic_mempool(
universe@571:         void *data,
universe@571:         size_t n
universe@571: ) {
universe@571:     of_chk_(n);
universe@571:     struct cx_basic_mempool_s *pool = data;
universe@571: 
universe@571:     if (pool->ndata >= pool->size) {
universe@571:         size_t newcap = pool->size * 2;
universe@571:         if (newcap < pool->size || cx_basic_mempool_chcap(pool, newcap)) {
universe@571:             return NULL;
universe@571:         }
universe@571:     }
universe@571: 
universe@572:     cx_basic_mempool_memory *mem = malloc(sizeof(cx_destructor_func) + n);
universe@571:     if (mem == NULL) {
universe@571:         return NULL;
universe@571:     }
universe@571: 
universe@571:     mem->destructor = NULL;
universe@571:     pool->data[pool->ndata] = mem;
universe@571:     pool->ndata++;
universe@571: 
universe@571:     return &(mem->c);
universe@571: }
universe@571: 
universe@571: void *cx_calloc_basic_mempool(
universe@571:         void *data,
universe@571:         size_t nelem,
universe@571:         size_t elsize
universe@571: ) {
universe@571:     size_t msz;
universe@571:     if (cx_szmul(nelem, elsize, &msz)) {
universe@571:         return NULL;
universe@571:     }
universe@571:     void *ptr = cx_malloc_basic_mempool(data, msz);
universe@571:     if (ptr == NULL) {
universe@571:         return NULL;
universe@571:     }
universe@571:     memset(ptr, 0, nelem * elsize);
universe@571:     return ptr;
universe@571: }
universe@571: 
universe@571: void *cx_realloc_basic_mempool(
universe@571:         void *data,
universe@571:         void *ptr,
universe@571:         size_t n
universe@571: ) {
universe@571:     of_chk_(n);
universe@571:     struct cx_basic_mempool_s *pool = data;
universe@571: 
universe@571:     char *mem = ((char *) ptr) - sizeof(cx_destructor_func);
universe@572:     char *newm = (char *) realloc(mem, n + sizeof(cx_destructor_func));
universe@571:     if (newm == NULL) {
universe@571:         return NULL;
universe@571:     }
universe@571:     if (mem != newm) {
universe@571:         cx_for_n(i, pool->ndata) {
universe@571:             if (pool->data[i] == mem) {
universe@571:                 pool->data[i] = newm;
universe@571:                 return newm + sizeof(cx_destructor_func);
universe@571:             }
universe@571:         }
universe@571:         abort();
universe@571:     } else {
universe@571:         return newm + sizeof(cx_destructor_func);
universe@571:     }
universe@571: }
universe@571: 
universe@571: void cx_free_basic_mempool(
universe@571:         void *data,
universe@571:         void *ptr
universe@571: ) {
universe@571:     struct cx_basic_mempool_s *pool = data;
universe@571: 
universe@571:     cx_basic_mempool_memory *mem = (cx_basic_mempool_memory *)
universe@571:             ((char *) ptr - sizeof(cx_destructor_func));
universe@571:     cx_for_n(i, pool->ndata) {
universe@571:         if (mem == pool->data[i]) {
universe@571:             if (mem->destructor != NULL) {
universe@571:                 mem->destructor(&(mem->c));
universe@571:             }
universe@572:             free(mem);
universe@571:             size_t last_index = pool->ndata - 1;
universe@571:             if (i != last_index) {
universe@571:                 pool->data[i] = pool->data[last_index];
universe@571:                 pool->data[last_index] = NULL;
universe@571:             }
universe@571:             pool->ndata--;
universe@571:             return;
universe@571:         }
universe@571:     }
universe@571:     abort();
universe@571: }
universe@571: 
universe@571: void cx_basic_mempool_destroy(CxMempool *p) {
universe@571:     struct cx_basic_mempool_s *pool = (struct cx_basic_mempool_s *) p;
universe@571:     cx_basic_mempool_memory *mem;
universe@571:     cx_for_n(i, pool->ndata) {
universe@571:         mem = (cx_basic_mempool_memory *) pool->data[i];
universe@571:         if (mem) {
universe@571:             if (mem->destructor) {
universe@571:                 mem->destructor(&(mem->c));
universe@571:             }
universe@572:             free(mem);
universe@571:         }
universe@571:     }
universe@571:     free(pool->data);
universe@571:     free((void *) p->allocator);
universe@571:     free(pool);
universe@571: }
universe@571: 
universe@571: void cx_basic_mempool_set_destr(
universe@571:         __attribute__((__unused__)) CxMempool *pool,
universe@571:         void *ptr,
universe@571:         cx_destructor_func func
universe@571: ) {
universe@571:     *(cx_destructor_func *) ((char *) ptr - sizeof(cx_destructor_func)) = func;
universe@571: }
universe@571: 
universe@571: static cx_allocator_class cx_basic_mempool_allocator_class = {
universe@571:         cx_malloc_basic_mempool,
universe@571:         cx_realloc_basic_mempool,
universe@571:         cx_calloc_basic_mempool,
universe@571:         cx_free_basic_mempool
universe@571: };
universe@571: 
universe@571: static cx_mempool_class cx_basic_mempool_class = {
universe@571:         cx_basic_mempool_destroy,
universe@571:         cx_basic_mempool_set_destr,
universe@571: };
universe@571: 
universe@572: CxMempool *cxBasicMempoolCreate(size_t capacity) {
universe@571:     size_t poolsize;
universe@571:     if (cx_szmul(capacity, sizeof(void *), &poolsize)) {
universe@571:         return NULL;
universe@571:     }
universe@571: 
universe@571:     struct cx_basic_mempool_s *pool =
universe@571:             malloc(sizeof(struct cx_basic_mempool_s));
universe@571:     if (pool == NULL) {
universe@571:         return NULL;
universe@571:     }
universe@571: 
universe@571: 
universe@571:     CxAllocator *provided_allocator = malloc(sizeof(CxAllocator));
universe@571:     if (!provided_allocator) {
universe@571:         free(pool);
universe@571:         return NULL;
universe@571:     }
universe@571:     provided_allocator->cl = &cx_basic_mempool_allocator_class;
universe@571:     provided_allocator->data = pool;
universe@571: 
universe@571:     pool->base.cl = &cx_basic_mempool_class;
universe@571:     pool->base.allocator = provided_allocator;
universe@571: 
universe@571:     pool->data = malloc(poolsize);
universe@571:     if (pool->data == NULL) {
universe@571:         free(provided_allocator);
universe@571:         free(pool);
universe@571:         return NULL;
universe@571:     }
universe@571: 
universe@571:     pool->ndata = 0;
universe@571:     pool->size = capacity;
universe@571: 
universe@571:     return (CxMempool *) pool;
universe@571: }