--- /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/mempool.h"
+#include "cx/utils.h"
+#include <string.h>
+
+struct cx_mempool_memory_s {
+ /** The destructor. */
+ cx_destructor_func destructor;
+ /** The actual memory. */
+ char c[];
+};
+
+static void *cx_mempool_malloc(
+ void *p,
+ size_t n
+) {
+ struct cx_mempool_s *pool = p;
+
+ if (pool->size >= pool->capacity) {
+ size_t newcap = pool->capacity - (pool->capacity % 16) + 16;
+ struct cx_mempool_memory_s **newdata = realloc(pool->data, newcap*sizeof(struct cx_mempool_memory_s*));
+ if (newdata == NULL) {
+ return NULL;
+ }
+ pool->data = newdata;
+ pool->capacity = newcap;
+ }
+
+ struct cx_mempool_memory_s *mem = malloc(sizeof(cx_destructor_func) + n);
+ if (mem == NULL) {
+ return NULL;
+ }
+
+ mem->destructor = pool->auto_destr;
+ pool->data[pool->size] = mem;
+ pool->size++;
+
+ return mem->c;
+}
+
+static void *cx_mempool_calloc(
+ void *p,
+ size_t nelem,
+ size_t elsize
+) {
+ size_t msz;
+ if (cx_szmul(nelem, elsize, &msz)) {
+ return NULL;
+ }
+ void *ptr = cx_mempool_malloc(p, msz);
+ if (ptr == NULL) {
+ return NULL;
+ }
+ memset(ptr, 0, nelem * elsize);
+ return ptr;
+}
+
+static void *cx_mempool_realloc(
+ void *p,
+ void *ptr,
+ size_t n
+) {
+ struct cx_mempool_s *pool = p;
+
+ struct cx_mempool_memory_s *mem, *newm;
+ mem = (struct cx_mempool_memory_s*)(((char *) ptr) - sizeof(cx_destructor_func));
+ newm = realloc(mem, n + sizeof(cx_destructor_func));
+
+ if (newm == NULL) {
+ return NULL;
+ }
+ if (mem != newm) {
+ cx_for_n(i, pool->size) {
+ if (pool->data[i] == mem) {
+ pool->data[i] = newm;
+ return ((char*)newm) + sizeof(cx_destructor_func);
+ }
+ }
+ abort();
+ } else {
+ return ptr;
+ }
+}
+
+static void cx_mempool_free(
+ void *p,
+ void *ptr
+) {
+ struct cx_mempool_s *pool = p;
+
+ struct cx_mempool_memory_s *mem = (struct cx_mempool_memory_s *)
+ ((char *) ptr - sizeof(cx_destructor_func));
+
+ cx_for_n(i, pool->size) {
+ if (mem == pool->data[i]) {
+ if (mem->destructor) {
+ mem->destructor(mem->c);
+ }
+ free(mem);
+ size_t last_index = pool->size - 1;
+ if (i != last_index) {
+ pool->data[i] = pool->data[last_index];
+ pool->data[last_index] = NULL;
+ }
+ pool->size--;
+ return;
+ }
+ }
+ abort();
+}
+
+void cxMempoolDestroy(CxMempool *pool) {
+ struct cx_mempool_memory_s *mem;
+ cx_for_n(i, pool->size) {
+ mem = pool->data[i];
+ if (mem->destructor) {
+ mem->destructor(mem->c);
+ }
+ free(mem);
+ }
+ free(pool->data);
+ free((void*) pool->allocator);
+ free(pool);
+}
+
+void cxMempoolSetDestructor(
+ void *ptr,
+ cx_destructor_func func
+) {
+ *(cx_destructor_func *) ((char *) ptr - sizeof(cx_destructor_func)) = func;
+}
+
+struct cx_mempool_foreign_mem_s {
+ cx_destructor_func destr;
+ void* mem;
+};
+
+static void cx_mempool_destr_foreign_mem(void* ptr) {
+ struct cx_mempool_foreign_mem_s *fm = ptr;
+ fm->destr(fm->mem);
+}
+
+int cxMempoolRegister(
+ CxMempool *pool,
+ void *memory,
+ cx_destructor_func destr
+) {
+ struct cx_mempool_foreign_mem_s *fm = cx_mempool_malloc(
+ pool,
+ sizeof(struct cx_mempool_foreign_mem_s)
+ );
+ if (fm == NULL) return 1;
+
+ fm->mem = memory;
+ fm->destr = destr;
+ *(cx_destructor_func *) ((char *) fm - sizeof(cx_destructor_func)) = cx_mempool_destr_foreign_mem;
+
+ return 0;
+}
+
+static cx_allocator_class cx_mempool_allocator_class = {
+ cx_mempool_malloc,
+ cx_mempool_realloc,
+ cx_mempool_calloc,
+ cx_mempool_free
+};
+
+CxMempool *cxMempoolCreate(
+ size_t capacity,
+ cx_destructor_func destr
+) {
+ size_t poolsize;
+ if (cx_szmul(capacity, sizeof(struct cx_mempool_memory_s*), &poolsize)) {
+ return NULL;
+ }
+
+ struct cx_mempool_s *pool =
+ malloc(sizeof(struct cx_mempool_s));
+ if (pool == NULL) {
+ return NULL;
+ }
+
+ CxAllocator *provided_allocator = malloc(sizeof(CxAllocator));
+ if (provided_allocator == NULL) {
+ free(pool);
+ return NULL;
+ }
+ provided_allocator->cl = &cx_mempool_allocator_class;
+ provided_allocator->data = pool;
+
+ pool->allocator = provided_allocator;
+
+ pool->data = malloc(poolsize);
+ if (pool->data == NULL) {
+ free(provided_allocator);
+ free(pool);
+ return NULL;
+ }
+
+ pool->size = 0;
+ pool->capacity = capacity;
+ pool->auto_destr = destr;
+
+ return (CxMempool *) pool;
+}