--- /dev/null
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2021 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 "cx/basic_mempool.h"
+#include "cx/utils.h"
+#include <string.h>
+
+#define of_chk_(n) if (SIZE_MAX - sizeof(cx_destructor_func) < (n)) return NULL
+
+/** Internal structure for denoting pooled memory. */
+typedef struct {
+ /** The destructor. */
+ cx_destructor_func destructor;
+ /**
+ * Access to the first byte of the polled memory.
+ */
+ char c;
+} cx_basic_mempool_memory;
+
+static int cx_basic_mempool_chcap(
+ struct cx_basic_mempool_s *pool,
+ size_t newcap
+) {
+ if (newcap < pool->ndata) {
+ return 1;
+ }
+
+ size_t newcapsz;
+ if (cx_szmul(newcap, sizeof(void *), &newcapsz)) {
+ return 1;
+ }
+
+ void **data = realloc(pool->data, newcapsz);
+ if (data) {
+ pool->data = data;
+ pool->size = newcap;
+ return 0;
+ } else {
+ return 1;
+ }
+}
+
+void *cx_malloc_basic_mempool(
+ void *data,
+ size_t n
+) {
+ of_chk_(n);
+ struct cx_basic_mempool_s *pool = data;
+
+ if (pool->ndata >= pool->size) {
+ size_t newcap = pool->size * 2;
+ if (newcap < pool->size || cx_basic_mempool_chcap(pool, newcap)) {
+ return NULL;
+ }
+ }
+
+ cx_basic_mempool_memory *mem = malloc(sizeof(cx_destructor_func) + n);
+ if (mem == NULL) {
+ return NULL;
+ }
+
+ mem->destructor = NULL;
+ pool->data[pool->ndata] = mem;
+ pool->ndata++;
+
+ return &(mem->c);
+}
+
+void *cx_calloc_basic_mempool(
+ void *data,
+ size_t nelem,
+ size_t elsize
+) {
+ size_t msz;
+ if (cx_szmul(nelem, elsize, &msz)) {
+ return NULL;
+ }
+ void *ptr = cx_malloc_basic_mempool(data, msz);
+ if (ptr == NULL) {
+ return NULL;
+ }
+ memset(ptr, 0, nelem * elsize);
+ return ptr;
+}
+
+void *cx_realloc_basic_mempool(
+ void *data,
+ void *ptr,
+ size_t n
+) {
+ of_chk_(n);
+ struct cx_basic_mempool_s *pool = data;
+
+ char *mem = ((char *) ptr) - sizeof(cx_destructor_func);
+ char *newm = (char *) realloc(mem, n + sizeof(cx_destructor_func));
+ if (newm == NULL) {
+ return NULL;
+ }
+ if (mem != newm) {
+ cx_for_n(i, pool->ndata) {
+ if (pool->data[i] == mem) {
+ pool->data[i] = newm;
+ return newm + sizeof(cx_destructor_func);
+ }
+ }
+ abort();
+ } else {
+ return newm + sizeof(cx_destructor_func);
+ }
+}
+
+void cx_free_basic_mempool(
+ void *data,
+ void *ptr
+) {
+ struct cx_basic_mempool_s *pool = data;
+
+ cx_basic_mempool_memory *mem = (cx_basic_mempool_memory *)
+ ((char *) ptr - sizeof(cx_destructor_func));
+ cx_for_n(i, pool->ndata) {
+ if (mem == pool->data[i]) {
+ if (mem->destructor != NULL) {
+ mem->destructor(&(mem->c));
+ }
+ free(mem);
+ size_t last_index = pool->ndata - 1;
+ if (i != last_index) {
+ pool->data[i] = pool->data[last_index];
+ pool->data[last_index] = NULL;
+ }
+ pool->ndata--;
+ return;
+ }
+ }
+ abort();
+}
+
+void cx_basic_mempool_destroy(CxMempool *p) {
+ struct cx_basic_mempool_s *pool = (struct cx_basic_mempool_s *) p;
+ cx_basic_mempool_memory *mem;
+ cx_for_n(i, pool->ndata) {
+ mem = (cx_basic_mempool_memory *) pool->data[i];
+ if (mem) {
+ if (mem->destructor) {
+ mem->destructor(&(mem->c));
+ }
+ free(mem);
+ }
+ }
+ free(pool->data);
+ free((void *) p->allocator);
+ free(pool);
+}
+
+void cx_basic_mempool_set_destr(
+ __attribute__((__unused__)) CxMempool *pool,
+ void *ptr,
+ cx_destructor_func func
+) {
+ *(cx_destructor_func *) ((char *) ptr - sizeof(cx_destructor_func)) = func;
+}
+
+static cx_allocator_class cx_basic_mempool_allocator_class = {
+ cx_malloc_basic_mempool,
+ cx_realloc_basic_mempool,
+ cx_calloc_basic_mempool,
+ cx_free_basic_mempool
+};
+
+static cx_mempool_class cx_basic_mempool_class = {
+ cx_basic_mempool_destroy,
+ cx_basic_mempool_set_destr,
+};
+
+CxMempool *cxBasicMempoolCreate(size_t capacity) {
+ size_t poolsize;
+ if (cx_szmul(capacity, sizeof(void *), &poolsize)) {
+ return NULL;
+ }
+
+ struct cx_basic_mempool_s *pool =
+ malloc(sizeof(struct cx_basic_mempool_s));
+ if (pool == NULL) {
+ return NULL;
+ }
+
+
+ CxAllocator *provided_allocator = malloc(sizeof(CxAllocator));
+ if (!provided_allocator) {
+ free(pool);
+ return NULL;
+ }
+ provided_allocator->cl = &cx_basic_mempool_allocator_class;
+ provided_allocator->data = pool;
+
+ pool->base.cl = &cx_basic_mempool_class;
+ pool->base.allocator = provided_allocator;
+
+ pool->data = malloc(poolsize);
+ if (pool->data == NULL) {
+ free(provided_allocator);
+ free(pool);
+ return NULL;
+ }
+
+ pool->ndata = 0;
+ pool->size = capacity;
+
+ return (CxMempool *) pool;
+}