c_src/async_nif.h

@@ -0,0 +1,305 @@
+/*
+ *
+ * async_nif: An async thread-pool layer for Erlang's NIF API
+ *
+ * Copyright (c) 2012 Basho Technologies, Inc. All Rights Reserved.
+ * Author: Gregory Burd <greg@basho.com> <greg@burd.me>
+ *
+ * This file is provided to you under the Apache License,
+ * Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License.  You may obtain
+ * a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#ifndef __ASYNC_NIF_H__
+#define __ASYNC_NIF_H__
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+/* Redefine this in your NIF implementation before including this file to
+   change the thread pool size.  The maximum number of threads might be
+   bounded on your OS.  For instance, to allow 1,000,000 threads on a Linux
+   system you must do the following before launching the process.
+     echo 1000000 > /proc/sys/kernel/threads-max
+   and for all UNIX systems there will be ulimit maximums. */
+#ifndef ANIF_MAX_WORKERS
+#define ANIF_MAX_WORKERS 64
+#endif
+
+#ifndef __offsetof
+#define __offsetof(st, m) \
+     ((size_t) ( (char *)&((st *)0)->m - (char *)0 ))
+#endif
+#include "queue.h"
+
+struct anif_req_entry {
+  ERL_NIF_TERM pid;
+  ErlNifEnv *env;
+  ERL_NIF_TERM ref, *argv;
+  void *args;
+  void *priv_data;
+  void (*fn_work)(ErlNifEnv*, ERL_NIF_TERM, void *, ErlNifPid*, void *);
+  void (*fn_post)(void *);
+  STAILQ_ENTRY(anif_req_entry) entries;
+};
+STAILQ_HEAD(reqs, anif_req_entry) anif_reqs = STAILQ_HEAD_INITIALIZER(anif_reqs);
+
+struct anif_worker_entry {
+  ErlNifTid tid;
+  LIST_ENTRY(anif_worker_entry) entries;
+};
+LIST_HEAD(idle_workers, anif_worker_entry) anif_idle_workers = LIST_HEAD_INITIALIZER(anif_worker);
+
+static volatile unsigned int anif_req_count = 0;
+static volatile unsigned int anif_shutdown = 0;
+static ErlNifMutex *anif_req_mutex = NULL;
+static ErlNifMutex *anif_worker_mutex = NULL;
+static ErlNifCond *anif_cnd = NULL;
+static struct anif_worker_entry anif_worker_entries[ANIF_MAX_WORKERS];
+
+#define ASYNC_NIF_DECL(decl, frame, pre_block, work_block, post_block)  \
+  struct decl ## _args frame;                                           \
+  static void fn_work_ ## decl (ErlNifEnv *env, ERL_NIF_TERM ref, void *priv_data, ErlNifPid *pid, struct decl ## _args *args) \
+       work_block                                                       \
+  static void fn_post_ ## decl (struct decl ## _args *args) {           \
+    do post_block while(0);                                             \
+  }                                                                     \
+  static ERL_NIF_TERM decl(ErlNifEnv* env_in, int argc_in, const ERL_NIF_TERM argv_in[]) { \
+    struct decl ## _args on_stack_args;                                 \
+    struct decl ## _args *args = &on_stack_args;                        \
+    struct decl ## _args *copy_of_args;                                 \
+    struct anif_req_entry *req = NULL;                                  \
+    ErlNifPid pid_in;                                                   \
+    ErlNifEnv *env = NULL;                                              \
+    ERL_NIF_TERM ref;                                                   \
+    ERL_NIF_TERM *argv = NULL;                                          \
+    int __i = 0, argc = argc_in - 1;                                    \
+    enif_self(env_in, &pid_in);                                         \
+    if (anif_shutdown) {                                                \
+      enif_send(NULL, &pid_in, env_in,                                  \
+                enif_make_tuple2(env_in, enif_make_atom(env_in, "error"), \
+                                 enif_make_atom(env_in, "shutdown")));  \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "shutdown"));      \
+    }                                                                   \
+    env = enif_alloc_env();                                             \
+    if (!env)                                                           \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "enomem"));        \
+    ref = enif_make_copy(env, argv_in[0]);                              \
+    if (!ref) {                                                         \
+      enif_free_env(env);                                               \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "enomem"));        \
+    }                                                                   \
+    copy_of_args = (struct decl ## _args *)enif_alloc(sizeof(struct decl ## _args)); \
+    if (!copy_of_args) {                                                \
+      enif_free_env(env);                                               \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "enomem"));        \
+    }                                                                   \
+    argv = (ERL_NIF_TERM *)enif_alloc((sizeof(ERL_NIF_TERM) * argc));   \
+    if (!argv) {                                                        \
+      enif_free(copy_of_args);                                          \
+      enif_free_env(env);                                               \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "enomem"));        \
+    }                                                                   \
+    req = (struct anif_req_entry*)enif_alloc(sizeof(struct anif_req_entry)); \
+    if (!req) {                                                         \
+      enif_free(argv);                                                  \
+      enif_free(copy_of_args);                                          \
+      enif_free_env(env);                                               \
+      return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"),  \
+                              enif_make_atom(env_in, "enomem"));        \
+    }                                                                   \
+    for (__i = 0; __i < argc; __i++) {                                  \
+      argv[__i] = enif_make_copy(env, argv_in[(__i + 1)]);              \
+      if (!argv[__i]) {                                                 \
+        enif_free(req);                                                 \
+        enif_free(argv);                                                \
+        enif_free(copy_of_args);                                        \
+        enif_free_env(env);                                             \
+        return enif_make_tuple2(env_in, enif_make_atom(env_in, "error"), \
+                                enif_make_atom(env_in, "enomem"));      \
+      }                                                                 \
+    }                                                                   \
+    do pre_block while(0);                                              \
+    memcpy(copy_of_args, args, sizeof(struct decl ## _args));           \
+    req->ref = ref;                                                     \
+    req->pid = enif_make_pid(env, &pid_in);                             \
+    req->args = (void*)copy_of_args;                                    \
+    req->argv = argv;                                                   \
+    req->env = env;                                                     \
+    req->priv_data = enif_priv_data(env_in);                            \
+    req->fn_work = (void (*)(ErlNifEnv *, ERL_NIF_TERM, void*, ErlNifPid*, void *))fn_work_ ## decl ; \
+    req->fn_post = (void (*)(void *))fn_post_ ## decl;                  \
+    anif_enqueue_req(req);                                              \
+    return enif_make_tuple2(env, enif_make_atom(env, "ok"),             \
+                            enif_make_int(env, anif_req_count));        \
+  }
+
+#define ASYNC_NIF_LOAD() if (anif_init() != 0) return -1;
+#define ASYNC_NIF_UNLOAD() anif_unload();
+#define ASYNC_NIF_UPGRADE() anif_unload();
+
+#define ASYNC_NIF_PRE_ENV() env_in
+#define ASYNC_NIF_PRE_RETURN_CLEANUP() \
+  enif_free(argv);                              \
+  enif_free(copy_of_args);                      \
+  enif_free(req);                               \
+  enif_free_env(env);
+#define ASYNC_NIF_RETURN_BADARG() ASYNC_NIF_PRE_RETURN_CLEANUP(); return enif_make_badarg(env_in);
+
+#define ASYNC_NIF_REPLY(msg) enif_send(NULL, pid, env, enif_make_tuple2(env, ref, msg))
+
+static void anif_enqueue_req(struct anif_req_entry *r)
+{
+  /* Add the request to the work queue. */
+  enif_mutex_lock(anif_req_mutex);
+  STAILQ_INSERT_TAIL(&anif_reqs, r, entries);
+  anif_req_count++;
+  enif_mutex_unlock(anif_req_mutex);
+  enif_cond_broadcast(anif_cnd);
+}
+
+static void *anif_worker_fn(void *arg)
+{
+  struct anif_worker_entry *worker = (struct anif_worker_entry *)arg;
+  struct anif_req_entry *req = NULL;
+
+  /*
+   * Workers are active while there is work on the queue to do and
+   * only in the idle list when they are waiting on new work.
+   */
+  for(;;) {
+    /* Examine the request queue, are there things to be done? */
+    enif_mutex_lock(anif_req_mutex);
+    enif_mutex_lock(anif_worker_mutex);
+    LIST_INSERT_HEAD(&anif_idle_workers, worker, entries);
+    enif_mutex_unlock(anif_worker_mutex);
+    check_again_for_work:
+    if (anif_shutdown) { enif_mutex_unlock(anif_req_mutex); break; }
+    if ((req = STAILQ_FIRST(&anif_reqs)) == NULL) {
+      /* Queue is empty, join the list of idle workers and wait for work */
+      enif_cond_wait(anif_cnd, anif_req_mutex);
+      goto check_again_for_work;
+    } else {
+      /* `req` is our work request and we hold the lock. */
+      enif_cond_broadcast(anif_cnd);
+
+      /* Take the request off the queue. */
+      STAILQ_REMOVE(&anif_reqs, req, anif_req_entry, entries); anif_req_count--;
+
+      /* Now we need to remove this thread from the list of idle threads. */
+      enif_mutex_lock(anif_worker_mutex);
+      LIST_REMOVE(worker, entries);
+
+      /* Release the locks in reverse order that we acquired them,
+         so as not to self-deadlock. */
+      enif_mutex_unlock(anif_worker_mutex);
+      enif_mutex_unlock(anif_req_mutex);
+
+      /* Finally, let's do the work! :) */
+      ErlNifPid pid;
+      enif_get_local_pid(req->env, req->pid, &pid);
+      req->fn_work(req->env, req->ref, req->priv_data, &pid, req->args);
+      req->fn_post(req->args);
+      enif_free(req->args);
+      enif_free(req->argv);
+      enif_free_env(req->env);
+      enif_free(req);
+    }
+  }
+  enif_thread_exit(0);
+  return 0;
+}
+
+static void anif_unload(void)
+{
+  unsigned int i;
+
+  /* Signal the worker threads, stop what you're doing and exit. */
+  enif_mutex_lock(anif_req_mutex);
+  anif_shutdown = 1;
+  enif_cond_broadcast(anif_cnd);
+  enif_mutex_unlock(anif_req_mutex);
+
+  /* Join for the now exiting worker threads. */
+  for (i = 0; i < ANIF_MAX_WORKERS; ++i) {
+    void *exit_value = 0; /* Ignore this. */
+    enif_thread_join(anif_worker_entries[i].tid, &exit_value);
+  }
+
+  /* We won't get here until all threads have exited.
+     Patch things up, and carry on. */
+  enif_mutex_lock(anif_req_mutex);
+
+  /* Worker threads are stopped, now toss anything left in the queue. */
+  struct anif_req_entry *req = NULL;
+  STAILQ_FOREACH(req, &anif_reqs, entries) {
+    STAILQ_REMOVE(&anif_reqs, STAILQ_LAST(&anif_reqs, anif_req_entry, entries),
+                  anif_req_entry, entries);
+    ErlNifPid pid;
+    enif_get_local_pid(req->env, req->pid, &pid);
+    enif_send(NULL, &pid, req->env,
+              enif_make_tuple2(req->env, enif_make_atom(req->env, "error"),
+                               enif_make_atom(req->env, "shutdown")));
+    req->fn_post(req->args);
+    enif_free(req->args);
+    enif_free(req->argv);
+    enif_free_env(req->env);
+    enif_free(req);
+    anif_req_count--;
+  }
+  enif_mutex_unlock(anif_req_mutex);
+
+  enif_cond_destroy(anif_cnd);
+  /* Not strictly necessary. */
+  memset(anif_worker_entries, sizeof(struct anif_worker_entry) * ANIF_MAX_WORKERS, 0);
+
+  enif_mutex_destroy(anif_req_mutex); anif_req_mutex = NULL;
+  enif_mutex_destroy(anif_worker_mutex); anif_worker_mutex = NULL;
+}
+
+static int anif_init(void)
+{
+  unsigned int i;
+
+  /* Don't init more than once. */
+  if (anif_req_mutex) return 0;
+
+  anif_req_mutex = enif_mutex_create(NULL);
+  anif_worker_mutex = enif_mutex_create(NULL);
+  anif_cnd = enif_cond_create(NULL);
+
+  /* Setup the requests management. */
+  anif_req_count = 0;
+
+  /* Setup the thread pool management. */
+  enif_mutex_lock(anif_worker_mutex);
+  for (i = 0; i < ANIF_MAX_WORKERS; i++) {
+    enif_thread_create(NULL, &anif_worker_entries[i].tid,
+                       &anif_worker_fn, (void*)&anif_worker_entries[i], NULL);
+  }
+  enif_mutex_unlock(anif_worker_mutex);
+  return 0;
+}
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif // __ASYNC_NIF_H__

c_src/queue.h

@@ -0,0 +1,570 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 2012 Oracle and/or its affiliates.  All rights reserved.
+ */
+/*
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ *
+ *	@(#)queue.h	8.5 (Berkeley) 8/20/94
+ * $FreeBSD: src/sys/sys/queue.h,v 1.54 2002/08/05 05:18:43 alfred Exp $
+ */
+
+#ifndef	_DB_QUEUE_H_
+#define	_DB_QUEUE_H_
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+/*
+ * This file defines four types of data structures: singly-linked lists,
+ * singly-linked tail queues, lists and tail queues.
+ *
+ * A singly-linked list is headed by a single forward pointer. The elements
+ * are singly linked for minimum space and pointer manipulation overhead at
+ * the expense of O(n) removal for arbitrary elements. New elements can be
+ * added to the list after an existing element or at the head of the list.
+ * Elements being removed from the head of the list should use the explicit
+ * macro for this purpose for optimum efficiency. A singly-linked list may
+ * only be traversed in the forward direction.  Singly-linked lists are ideal
+ * for applications with large datasets and few or no removals or for
+ * implementing a LIFO queue.
+ *
+ * A singly-linked tail queue is headed by a pair of pointers, one to the
+ * head of the list and the other to the tail of the list. The elements are
+ * singly linked for minimum space and pointer manipulation overhead at the
+ * expense of O(n) removal for arbitrary elements. New elements can be added
+ * to the list after an existing element, at the head of the list, or at the
+ * end of the list. Elements being removed from the head of the tail queue
+ * should use the explicit macro for this purpose for optimum efficiency.
+ * A singly-linked tail queue may only be traversed in the forward direction.
+ * Singly-linked tail queues are ideal for applications with large datasets
+ * and few or no removals or for implementing a FIFO queue.
+ *
+ * A list is headed by a single forward pointer (or an array of forward
+ * pointers for a hash table header). The elements are doubly linked
+ * so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before
+ * or after an existing element or at the head of the list. A list
+ * may only be traversed in the forward direction.
+ *
+ * A tail queue is headed by a pair of pointers, one to the head of the
+ * list and the other to the tail of the list. The elements are doubly
+ * linked so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before or
+ * after an existing element, at the head of the list, or at the end of
+ * the list. A tail queue may be traversed in either direction.
+ *
+ * For details on the use of these macros, see the queue(3) manual page.
+ *
+ *
+ *			SLIST	LIST	STAILQ	TAILQ
+ * _HEAD		+	+	+	+
+ * _HEAD_INITIALIZER	+	+	+	+
+ * _ENTRY		+	+	+	+
+ * _INIT		+	+	+	+
+ * _EMPTY		+	+	+	+
+ * _FIRST		+	+	+	+
+ * _NEXT		+	+	+	+
+ * _PREV		-	-	-	+
+ * _LAST		-	-	+	+
+ * _FOREACH		+	+	+	+
+ * _FOREACH_REVERSE	-	-	-	+
+ * _INSERT_HEAD		+	+	+	+
+ * _INSERT_BEFORE	-	+	-	+
+ * _INSERT_AFTER	+	+	+	+
+ * _INSERT_TAIL		-	-	+	+
+ * _CONCAT		-	-	+	+
+ * _REMOVE_HEAD		+	-	+	-
+ * _REMOVE		+	+	+	+
+ *
+ */
+
+/*
+ * XXX
+ * We #undef all of the macros because there are incompatible versions of this
+ * file and these macros on various systems.  What makes the problem worse is
+ * they are included and/or defined by system include files which we may have
+ * already loaded into Berkeley DB before getting here.  For example, FreeBSD's
+ * <rpc/rpc.h> includes its system <sys/queue.h>, and VxWorks UnixLib.h defines
+ * several of the LIST_XXX macros.  Visual C.NET 7.0 also defines some of these
+ * same macros in Vc7\PlatformSDK\Include\WinNT.h.  Make sure we use ours.
+ */
+#undef LIST_EMPTY
+#undef LIST_ENTRY
+#undef LIST_FIRST
+#undef LIST_FOREACH
+#undef LIST_HEAD
+#undef LIST_HEAD_INITIALIZER
+#undef LIST_INIT
+#undef LIST_INSERT_AFTER
+#undef LIST_INSERT_BEFORE
+#undef LIST_INSERT_HEAD
+#undef LIST_NEXT
+#undef LIST_REMOVE
+#undef QMD_TRACE_ELEM
+#undef QMD_TRACE_HEAD
+#undef QUEUE_MACRO_DEBUG
+#undef SLIST_EMPTY
+#undef SLIST_ENTRY
+#undef SLIST_FIRST
+#undef SLIST_FOREACH
+#undef SLIST_FOREACH_PREVPTR
+#undef SLIST_HEAD
+#undef SLIST_HEAD_INITIALIZER
+#undef SLIST_INIT
+#undef SLIST_INSERT_AFTER
+#undef SLIST_INSERT_HEAD
+#undef SLIST_NEXT
+#undef SLIST_REMOVE
+#undef SLIST_REMOVE_HEAD
+#undef STAILQ_CONCAT
+#undef STAILQ_EMPTY
+#undef STAILQ_ENTRY
+#undef STAILQ_FIRST
+#undef STAILQ_FOREACH
+#undef STAILQ_HEAD
+#undef STAILQ_HEAD_INITIALIZER
+#undef STAILQ_INIT
+#undef STAILQ_INSERT_AFTER
+#undef STAILQ_INSERT_HEAD
+#undef STAILQ_INSERT_TAIL
+#undef STAILQ_LAST
+#undef STAILQ_NEXT
+#undef STAILQ_REMOVE
+#undef STAILQ_REMOVE_HEAD
+#undef STAILQ_REMOVE_HEAD_UNTIL
+#undef TAILQ_CONCAT
+#undef TAILQ_EMPTY
+#undef TAILQ_ENTRY
+#undef TAILQ_FIRST
+#undef TAILQ_FOREACH
+#undef TAILQ_FOREACH_REVERSE
+#undef TAILQ_HEAD
+#undef TAILQ_HEAD_INITIALIZER
+#undef TAILQ_INIT
+#undef TAILQ_INSERT_AFTER
+#undef TAILQ_INSERT_BEFORE
+#undef TAILQ_INSERT_HEAD
+#undef TAILQ_INSERT_TAIL
+#undef TAILQ_LAST
+#undef TAILQ_NEXT
+#undef TAILQ_PREV
+#undef TAILQ_REMOVE
+#undef TRACEBUF
+#undef TRASHIT
+
+#define	QUEUE_MACRO_DEBUG 0
+#if QUEUE_MACRO_DEBUG
+/* Store the last 2 places the queue element or head was altered */
+struct qm_trace {
+	char * lastfile;
+	int lastline;
+	char * prevfile;
+	int prevline;
+};
+
+#define	TRACEBUF	struct qm_trace trace;
+#define	TRASHIT(x)	do {(x) = (void *)-1;} while (0)
+
+#define	QMD_TRACE_HEAD(head) do {					\
+	(head)->trace.prevline = (head)->trace.lastline;		\
+	(head)->trace.prevfile = (head)->trace.lastfile;		\
+	(head)->trace.lastline = __LINE__;				\
+	(head)->trace.lastfile = __FILE__;				\
+} while (0)
+
+#define	QMD_TRACE_ELEM(elem) do {					\
+	(elem)->trace.prevline = (elem)->trace.lastline;		\
+	(elem)->trace.prevfile = (elem)->trace.lastfile;		\
+	(elem)->trace.lastline = __LINE__;				\
+	(elem)->trace.lastfile = __FILE__;				\
+} while (0)
+
+#else
+#define	QMD_TRACE_ELEM(elem)
+#define	QMD_TRACE_HEAD(head)
+#define	TRACEBUF
+#define	TRASHIT(x)
+#endif	/* QUEUE_MACRO_DEBUG */
+
+/*
+ * Singly-linked List declarations.
+ */
+#define	SLIST_HEAD(name, type)						\
+struct name {								\
+	struct type *slh_first;	/* first element */			\
+}
+
+#define	SLIST_HEAD_INITIALIZER(head)					\
+	{ NULL }
+
+#define	SLIST_ENTRY(type)						\
+struct {								\
+	struct type *sle_next;	/* next element */			\
+}
+
+/*
+ * Singly-linked List functions.
+ */
+#define	SLIST_EMPTY(head)	((head)->slh_first == NULL)
+
+#define	SLIST_FIRST(head)	((head)->slh_first)
+
+#define	SLIST_FOREACH(var, head, field)					\
+	for ((var) = SLIST_FIRST((head));				\
+	    (var);							\
+	    (var) = SLIST_NEXT((var), field))
+
+#define	SLIST_FOREACH_PREVPTR(var, varp, head, field)			\
+	for ((varp) = &SLIST_FIRST((head));				\
+	    ((var) = *(varp)) != NULL;					\
+	    (varp) = &SLIST_NEXT((var), field))
+
+#define	SLIST_INIT(head) do {						\
+	SLIST_FIRST((head)) = NULL;					\
+} while (0)
+
+#define	SLIST_INSERT_AFTER(slistelm, elm, field) do {			\
+	SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field);	\
+	SLIST_NEXT((slistelm), field) = (elm);				\
+} while (0)
+
+#define	SLIST_INSERT_HEAD(head, elm, field) do {			\
+	SLIST_NEXT((elm), field) = SLIST_FIRST((head));			\
+	SLIST_FIRST((head)) = (elm);					\
+} while (0)
+
+#define	SLIST_NEXT(elm, field)	((elm)->field.sle_next)
+
+#define	SLIST_REMOVE(head, elm, type, field) do {			\
+	if (SLIST_FIRST((head)) == (elm)) {				\
+		SLIST_REMOVE_HEAD((head), field);			\
+	}								\
+	else {								\
+		struct type *curelm = SLIST_FIRST((head));		\
+		while (curelm != NULL && 				\
+		    SLIST_NEXT(curelm, field) != (elm))			\
+			curelm = SLIST_NEXT(curelm, field);		\
+		if (curelm != NULL)					\
+			SLIST_NEXT(curelm, field) =			\
+			    SLIST_NEXT(SLIST_NEXT(curelm, field), field);\
+	}								\
+} while (0)
+
+#define	SLIST_REMOVE_HEAD(head, field) do {				\
+	SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field);	\
+} while (0)
+
+/*
+ * Singly-linked Tail queue declarations.
+ */
+#define	STAILQ_HEAD(name, type)						\
+struct name {								\
+	struct type *stqh_first;/* first element */			\
+	struct type **stqh_last;/* addr of last next element */		\
+}
+
+#define	STAILQ_HEAD_INITIALIZER(head)					\
+	{ NULL, &(head).stqh_first }
+
+#define	STAILQ_ENTRY(type)						\
+struct {								\
+	struct type *stqe_next;	/* next element */			\
+}
+
+/*
+ * Singly-linked Tail queue functions.
+ */
+#define	STAILQ_CONCAT(head1, head2) do {				\
+	if (!STAILQ_EMPTY((head2))) {					\
+		*(head1)->stqh_last = (head2)->stqh_first;		\
+		(head1)->stqh_last = (head2)->stqh_last;		\
+		STAILQ_INIT((head2));					\
+	}								\
+} while (0)
+
+#define	STAILQ_EMPTY(head)	((head)->stqh_first == NULL)
+
+#define	STAILQ_FIRST(head)	((head)->stqh_first)
+
+#define	STAILQ_FOREACH(var, head, field)				\
+	for ((var) = STAILQ_FIRST((head));				\
+	   (var);							\
+	   (var) = STAILQ_NEXT((var), field))
+
+#define	STAILQ_INIT(head) do {						\
+	STAILQ_FIRST((head)) = NULL;					\
+	(head)->stqh_last = &STAILQ_FIRST((head));			\
+} while (0)
+
+#define	STAILQ_INSERT_AFTER(head, tqelm, elm, field) do {		\
+	if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\
+		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
+	STAILQ_NEXT((tqelm), field) = (elm);				\
+} while (0)
+
+#define	STAILQ_INSERT_HEAD(head, elm, field) do {			\
+	if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL)	\
+		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
+	STAILQ_FIRST((head)) = (elm);					\
+} while (0)
+
+#define	STAILQ_INSERT_TAIL(head, elm, field) do {			\
+	STAILQ_NEXT((elm), field) = NULL;				\
+	*(head)->stqh_last = (elm);					\
+	(head)->stqh_last = &STAILQ_NEXT((elm), field);			\
+} while (0)
+
+#define	STAILQ_LAST(head, type, field)					\
+	(STAILQ_EMPTY((head)) ?						\
+		NULL :							\
+		((struct type *)					\
+		((char *)((head)->stqh_last) - __offsetof(struct type, field))))
+
+#define	STAILQ_NEXT(elm, field)	((elm)->field.stqe_next)
+
+#define	STAILQ_REMOVE(head, elm, type, field) do {			\
+	if (STAILQ_FIRST((head)) == (elm)) {				\
+		STAILQ_REMOVE_HEAD((head), field);			\
+	}								\
+	else {								\
+		struct type *curelm = STAILQ_FIRST((head));		\
+		while (STAILQ_NEXT(curelm, field) != (elm))		\
+			curelm = STAILQ_NEXT(curelm, field);		\
+		if ((STAILQ_NEXT(curelm, field) =			\
+		     STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\
+			(head)->stqh_last = &STAILQ_NEXT((curelm), field);\
+	}								\
+} while (0)
+
+#define	STAILQ_REMOVE_HEAD(head, field) do {				\
+	if ((STAILQ_FIRST((head)) =					\
+	     STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL)		\
+		(head)->stqh_last = &STAILQ_FIRST((head));		\
+} while (0)
+
+#define	STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do {			\
+	if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL)	\
+		(head)->stqh_last = &STAILQ_FIRST((head));		\
+} while (0)
+
+/*
+ * List declarations.
+ */
+#define	LIST_HEAD(name, type)						\
+struct name {								\
+	struct type *lh_first;	/* first element */			\
+}
+
+#define	LIST_HEAD_INITIALIZER(head)					\
+	{ NULL }
+
+#define	LIST_ENTRY(type)						\
+struct {								\
+	struct type *le_next;	/* next element */			\
+	struct type **le_prev;	/* address of previous next element */	\
+}
+
+/*
+ * List functions.
+ */
+
+#define	LIST_EMPTY(head)	((head)->lh_first == NULL)
+
+#define	LIST_FIRST(head)	((head)->lh_first)
+
+#define	LIST_FOREACH(var, head, field)					\
+	for ((var) = LIST_FIRST((head));				\
+	    (var);							\
+	    (var) = LIST_NEXT((var), field))
+
+#define	LIST_INIT(head) do {						\
+	LIST_FIRST((head)) = NULL;					\
+} while (0)
+
+#define	LIST_INSERT_AFTER(listelm, elm, field) do {			\
+	if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\
+		LIST_NEXT((listelm), field)->field.le_prev =		\
+		    &LIST_NEXT((elm), field);				\
+	LIST_NEXT((listelm), field) = (elm);				\
+	(elm)->field.le_prev = &LIST_NEXT((listelm), field);		\
+} while (0)
+
+#define	LIST_INSERT_BEFORE(listelm, elm, field) do {			\
+	(elm)->field.le_prev = (listelm)->field.le_prev;		\
+	LIST_NEXT((elm), field) = (listelm);				\
+	*(listelm)->field.le_prev = (elm);				\
+	(listelm)->field.le_prev = &LIST_NEXT((elm), field);		\
+} while (0)
+
+#define	LIST_INSERT_HEAD(head, elm, field) do {				\
+	if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL)	\
+		LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
+	LIST_FIRST((head)) = (elm);					\
+	(elm)->field.le_prev = &LIST_FIRST((head));			\
+} while (0)
+
+#define	LIST_NEXT(elm, field)	((elm)->field.le_next)
+
+#define	LIST_REMOVE(elm, field) do {					\
+	if (LIST_NEXT((elm), field) != NULL)				\
+		LIST_NEXT((elm), field)->field.le_prev =		\
+		    (elm)->field.le_prev;				\
+	*(elm)->field.le_prev = LIST_NEXT((elm), field);		\
+} while (0)
+
+/*
+ * Tail queue declarations.
+ */
+#define	TAILQ_HEAD(name, type)						\
+struct name {								\
+	struct type *tqh_first;	/* first element */			\
+	struct type **tqh_last;	/* addr of last next element */		\
+	TRACEBUF							\
+}
+
+#define	TAILQ_HEAD_INITIALIZER(head)					\
+	{ NULL, &(head).tqh_first }
+
+#define	TAILQ_ENTRY(type)						\
+struct {								\
+	struct type *tqe_next;	/* next element */			\
+	struct type **tqe_prev;	/* address of previous next element */	\
+	TRACEBUF							\
+}
+
+/*
+ * Tail queue functions.
+ */
+#define	TAILQ_CONCAT(head1, head2, field) do {				\
+	if (!TAILQ_EMPTY(head2)) {					\
+		*(head1)->tqh_last = (head2)->tqh_first;		\
+		(head2)->tqh_first->field.tqe_prev = (head1)->tqh_last;	\
+		(head1)->tqh_last = (head2)->tqh_last;			\
+		TAILQ_INIT((head2));					\
+		QMD_TRACE_HEAD(head);					\
+		QMD_TRACE_HEAD(head2);					\
+	}								\
+} while (0)
+
+#define	TAILQ_EMPTY(head)	((head)->tqh_first == NULL)
+
+#define	TAILQ_FIRST(head)	((head)->tqh_first)
+
+#define	TAILQ_FOREACH(var, head, field)					\
+	for ((var) = TAILQ_FIRST((head));				\
+	    (var);							\
+	    (var) = TAILQ_NEXT((var), field))
+
+#define	TAILQ_FOREACH_REVERSE(var, head, headname, field)		\
+	for ((var) = TAILQ_LAST((head), headname);			\
+	    (var);							\
+	    (var) = TAILQ_PREV((var), headname, field))
+
+#define	TAILQ_INIT(head) do {						\
+	TAILQ_FIRST((head)) = NULL;					\
+	(head)->tqh_last = &TAILQ_FIRST((head));			\
+	QMD_TRACE_HEAD(head);						\
+} while (0)
+
+#define	TAILQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\
+		TAILQ_NEXT((elm), field)->field.tqe_prev =		\
+		    &TAILQ_NEXT((elm), field);				\
+	else {								\
+		(head)->tqh_last = &TAILQ_NEXT((elm), field);		\
+		QMD_TRACE_HEAD(head);					\
+	}								\
+	TAILQ_NEXT((listelm), field) = (elm);				\
+	(elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field);		\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+	QMD_TRACE_ELEM(&listelm->field);				\
+} while (0)
+
+#define	TAILQ_INSERT_BEFORE(listelm, elm, field) do {			\
+	(elm)->field.tqe_prev = (listelm)->field.tqe_prev;		\
+	TAILQ_NEXT((elm), field) = (listelm);				\
+	*(listelm)->field.tqe_prev = (elm);				\
+	(listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field);		\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+	QMD_TRACE_ELEM(&listelm->field);				\
+} while (0)
+
+#define	TAILQ_INSERT_HEAD(head, elm, field) do {			\
+	if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL)	\
+		TAILQ_FIRST((head))->field.tqe_prev =			\
+		    &TAILQ_NEXT((elm), field);				\
+	else								\
+		(head)->tqh_last = &TAILQ_NEXT((elm), field);		\
+	TAILQ_FIRST((head)) = (elm);					\
+	(elm)->field.tqe_prev = &TAILQ_FIRST((head));			\
+	QMD_TRACE_HEAD(head);						\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+} while (0)
+
+#define	TAILQ_INSERT_TAIL(head, elm, field) do {			\
+	TAILQ_NEXT((elm), field) = NULL;				\
+	(elm)->field.tqe_prev = (head)->tqh_last;			\
+	*(head)->tqh_last = (elm);					\
+	(head)->tqh_last = &TAILQ_NEXT((elm), field);			\
+	QMD_TRACE_HEAD(head);						\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+} while (0)
+
+#define	TAILQ_LAST(head, headname)					\
+	(*(((struct headname *)((head)->tqh_last))->tqh_last))
+
+#define	TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
+
+#define	TAILQ_PREV(elm, headname, field)				\
+	(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+
+#define	TAILQ_REMOVE(head, elm, field) do {				\
+	if ((TAILQ_NEXT((elm), field)) != NULL)				\
+		TAILQ_NEXT((elm), field)->field.tqe_prev =		\
+		    (elm)->field.tqe_prev;				\
+	else {								\
+		(head)->tqh_last = (elm)->field.tqe_prev;		\
+		QMD_TRACE_HEAD(head);					\
+	}								\
+	*(elm)->field.tqe_prev = TAILQ_NEXT((elm), field);		\
+	TRASHIT((elm)->field.tqe_next);					\
+	TRASHIT((elm)->field.tqe_prev);					\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+} while (0)
+
+#if defined(__cplusplus)
+}
+#endif
+#endif	/* !_DB_QUEUE_H_ */

src/async_nif.hrl

@@ -0,0 +1,43 @@
+%% -------------------------------------------------------------------
+%%
+%% async_nif: An async thread-pool layer for Erlang's NIF API
+%%
+%% Copyright (c) 2012 Basho Technologies, Inc. All Rights Reserved.
+%% Author: Gregory Burd <greg@basho.com> <greg@burd.me>
+%%
+%% This file is provided to you under the Apache License,
+%% Version 2.0 (the "License"); you may not use this file
+%% except in compliance with the License.  You may obtain
+%% a copy of the License at
+%%
+%%   http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing,
+%% software distributed under the License is distributed on an
+%% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+%% KIND, either express or implied.  See the License for the
+%% specific language governing permissions and limitations
+%% under the License.
+%%
+%% -------------------------------------------------------------------
+
+-define(ASYNC_NIF_CALL(Fun, Args),
+        begin
+            NIFRef = erlang:make_ref(),
+            case erlang:apply(Fun, [NIFRef|Args]) of
+                {ok, QDepth} ->
+                    erlang:bump_reductions(100 * QDepth),
+                    receive
+                        {NIFRef, {error, shutdown}=Error} ->
+                            %% Work unit was not executed, requeue it?
+                            Error;
+                        {NIFRef, {error, _Reason}=Error} ->
+                            %% Work unit returned an error.
+                            Error;
+                        {NIFRef, Reply} ->
+                            Reply
+                    end;
+                Other ->
+                    Other
+            end
+        end).

src/wterl.erl

@@ -61,6 +61,8 @@
          fold_keys/3,
          fold/3]).
 
+-include("async_nif.hrl").
+
 -ifdef(TEST).
 -ifdef(EQC).
 -include_lib("eqc/include/eqc.hrl").
@@ -101,143 +103,259 @@ init() ->
     erlang:load_nif(filename:join(PrivDir, atom_to_list(?MODULE)), 0).
 
 -spec conn_open(string(), config()) -> {ok, connection()} | {error, term()}.
-conn_open(_HomeDir, _Config) ->
+conn_open(HomeDir, Config) ->
+    ?ASYNC_NIF_CALL(fun conn_open_nif/3, [HomeDir, Config]).
+
+-spec conn_open_nif(reference(), string(), config()) -> {ok, connection()} | {error, term()}.
+conn_open_nif(_AsyncRef, _HomeDir, _Config) ->
     ?nif_stub.
 
 -spec conn_close(connection()) -> ok | {error, term()}.
-conn_close(_ConnRef) ->
+conn_close(ConnRef) ->
+    ?ASYNC_NIF_CALL(fun conn_close_nif/2, [ConnRef]).
+
+-spec conn_close_nif(reference(), connection()) -> ok | {error, term()}.
+conn_close_nif(_AsyncRef, _ConnRef) ->
     ?nif_stub.
 
 -spec session_open(connection()) -> {ok, session()} | {error, term()}.
-session_open(_ConnRef) ->
+session_open(ConnRef) ->
+    ?ASYNC_NIF_CALL(fun session_open_nif/2, [ConnRef]).
+
+-spec session_open_nif(reference(), connection()) -> {ok, session()} | {error, term()}.
+session_open_nif(_AsyncRef, _ConnRef) ->
     ?nif_stub.
 
 -spec session_close(session()) -> ok | {error, term()}.
-session_close(_Ref) ->
+session_close(Ref) ->
+    ?ASYNC_NIF_CALL(fun session_close_nif/2, [Ref]).
+
+-spec session_close_nif(reference(), session()) -> ok | {error, term()}.
+session_close_nif(_AsyncRef, _Ref) ->
     ?nif_stub.
 
 -spec session_create(session(), string()) -> ok | {error, term()}.
 -spec session_create(session(), string(), config()) -> ok | {error, term()}.
 session_create(Ref, Name) ->
     session_create(Ref, Name, ?EMPTY_CONFIG).
-session_create(_Ref, _Name, _Config) ->
+session_create(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_create_nif/4, [Ref, Name, Config]).
+
+-spec session_create_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_create_nif(_AsyncNif, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec session_drop(session(), string()) -> ok | {error, term()}.
 -spec session_drop(session(), string(), config()) -> ok | {error, term()}.
 session_drop(Ref, Name) ->
     session_drop(Ref, Name, ?EMPTY_CONFIG).
-session_drop(_Ref, _Name, _Config) ->
+session_drop(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_drop_nif/4, [Ref, Name, Config]).
+
+-spec session_drop_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_drop_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec session_delete(session(), string(), key()) -> ok | {error, term()}.
-session_delete(_Ref, _Table, _Key) ->
+session_delete(Ref, Table, Key) ->
+    ?ASYNC_NIF_CALL(fun session_delete_nif/4, [Ref, Table, Key]).
+
+-spec session_delete_nif(reference(), session(), string(), key()) -> ok | {error, term()}.
+session_delete_nif(_AsyncRef, _Ref, _Table, _Key) ->
     ?nif_stub.
 
 -spec session_get(session(), string(), key()) -> {ok, value()} | not_found | {error, term()}.
-session_get(_Ref, _Table, _Key) ->
+session_get(Ref, Table, Key) ->
+    ?ASYNC_NIF_CALL(fun session_get_nif/4, [Ref, Table, Key]).
+
+-spec session_get_nif(reference(), session(), string(), key()) -> {ok, value()} | not_found | {error, term()}.
+session_get_nif(_AsyncRef, _Ref, _Table, _Key) ->
     ?nif_stub.
 
 -spec session_put(session(), string(), key(), value()) -> ok | {error, term()}.
-session_put(_Ref, _Table, _Key, _Value) ->
+session_put(Ref, Table, Key, Value) ->
+    ?ASYNC_NIF_CALL(fun session_put_nif/5, [Ref, Table, Key, Value]).
+
+-spec session_put_nif(reference(), session(), string(), key(), value()) -> ok | {error, term()}.
+session_put_nif(_AsyncRef, _Ref, _Table, _Key, _Value) ->
     ?nif_stub.
 
 -spec session_rename(session(), string(), string()) -> ok | {error, term()}.
 -spec session_rename(session(), string(), string(), config()) -> ok | {error, term()}.
 session_rename(Ref, OldName, NewName) ->
     session_rename(Ref, OldName, NewName, ?EMPTY_CONFIG).
-session_rename(_Ref, _OldName, _NewName, _Config) ->
+session_rename(Ref, OldName, NewName, Config) ->
+    ?ASYNC_NIF_CALL(fun session_rename_nif/5, [Ref, OldName, NewName, Config]).
+
+-spec session_rename_nif(reference(), session(), string(), string(), config()) -> ok | {error, term()}.
+session_rename_nif(_AsyncRef, _Ref, _OldName, _NewName, _Config) ->
     ?nif_stub.
 
 -spec session_salvage(session(), string()) -> ok | {error, term()}.
 -spec session_salvage(session(), string(), config()) -> ok | {error, term()}.
 session_salvage(Ref, Name) ->
     session_salvage(Ref, Name, ?EMPTY_CONFIG).
-session_salvage(_Ref, _Name, _Config) ->
+session_salvage(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_salvage_nif/4, [Ref, Name, Config]).
+
+-spec session_salvage_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_salvage_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec session_checkpoint(session()) -> ok | {error, term()}.
 -spec session_checkpoint(session(), config()) -> ok | {error, term()}.
 session_checkpoint(_Ref) ->
     session_checkpoint(_Ref, ?EMPTY_CONFIG).
-session_checkpoint(_Ref, _Config) ->
+session_checkpoint(Ref, Config) ->
+    ?ASYNC_NIF_CALL(fun session_checkpoint_nif/3, [Ref, Config]).
+
+-spec session_checkpoint_nif(reference(), session(), config()) -> ok | {error, term()}.
+session_checkpoint_nif(_AsyncRef, _Ref, _Config) ->
     ?nif_stub.
 
 -spec session_truncate(session(), string()) -> ok | {error, term()}.
 -spec session_truncate(session(), string(), config()) -> ok | {error, term()}.
 session_truncate(Ref, Name) ->
     session_truncate(Ref, Name, ?EMPTY_CONFIG).
-session_truncate(_Ref, _Name, _Config) ->
+session_truncate(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_truncate_nif/4, [Ref, Name, Config]).
+
+-spec session_truncate_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_truncate_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec session_upgrade(session(), string()) -> ok | {error, term()}.
 -spec session_upgrade(session(), string(), config()) -> ok | {error, term()}.
 session_upgrade(Ref, Name) ->
     session_upgrade(Ref, Name, ?EMPTY_CONFIG).
-session_upgrade(_Ref, _Name, _Config) ->
+session_upgrade(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_upgrade_nif/4, [Ref, Name, Config]).
+
+-spec session_upgrade_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_upgrade_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec session_verify(session(), string()) -> ok | {error, term()}.
 -spec session_verify(session(), string(), config()) -> ok | {error, term()}.
 session_verify(Ref, Name) ->
     session_verify(Ref, Name, ?EMPTY_CONFIG).
-session_verify(_Ref, _Name, _Config) ->
+session_verify(Ref, Name, Config) ->
+    ?ASYNC_NIF_CALL(fun session_verify_nif/4, [Ref, Name, Config]).
+
+-spec session_verify_nif(reference(), session(), string(), config()) -> ok | {error, term()}.
+session_verify_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
 -spec cursor_open(session(), string()) -> {ok, cursor()} | {error, term()}.
-cursor_open(_Ref, _Table) ->
+cursor_open(Ref, Table) ->
+    ?ASYNC_NIF_CALL(fun cursor_open_nif/3, [Ref, Table]).
+
+-spec cursor_open_nif(reference(), session(), string()) -> {ok, cursor()} | {error, term()}.
+cursor_open_nif(_AsyncRef, _Ref, _Table) ->
     ?nif_stub.
 
 -spec cursor_close(cursor()) -> ok | {error, term()}.
-cursor_close(_Cursor) ->
+cursor_close(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_close_nif/2, [Cursor]).
+
+-spec cursor_close_nif(reference(), cursor()) -> ok | {error, term()}.
+cursor_close_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_next(cursor()) -> {ok, key(), value()} | not_found | {error, term()}.
-cursor_next(_Cursor) ->
+cursor_next(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_next_nif/2, [Cursor]).
+
+-spec cursor_next_nif(reference(), cursor()) -> {ok, key(), value()} | not_found | {error, term()}.
+cursor_next_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_next_key(cursor()) -> {ok, key()} | not_found | {error, term()}.
-cursor_next_key(_Cursor) ->
+cursor_next_key(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_next_key_nif/2, [Cursor]).
+
+-spec cursor_next_key_nif(reference(), cursor()) -> {ok, key()} | not_found | {error, term()}.
+cursor_next_key_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_next_value(cursor()) -> {ok, value()} | not_found | {error, term()}.
-cursor_next_value(_Cursor) ->
+cursor_next_value(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_next_value_nif/2, [Cursor]).
+
+-spec cursor_next_value_nif(reference(), cursor()) -> {ok, value()} | not_found | {error, term()}.
+cursor_next_value_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_prev(cursor()) -> {ok, key(), value()} | not_found | {error, term()}.
-cursor_prev(_Cursor) ->
+cursor_prev(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_prev_nif/2, [Cursor]).
+
+-spec cursor_prev_nif(reference(), cursor()) -> {ok, key(), value()} | not_found | {error, term()}.
+cursor_prev_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_prev_key(cursor()) -> {ok, key()} | not_found | {error, term()}.
-cursor_prev_key(_Cursor) ->
+cursor_prev_key(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_prev_key_nif/2, [Cursor]).
+
+-spec cursor_prev_key_nif(reference(), cursor()) -> {ok, key()} | not_found | {error, term()}.
+cursor_prev_key_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_prev_value(cursor()) -> {ok, value()} | not_found | {error, term()}.
-cursor_prev_value(_Cursor) ->
+cursor_prev_value(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_prev_value_nif/2, [Cursor]).
+
+-spec cursor_prev_value_nif(reference(), cursor()) -> {ok, value()} | not_found | {error, term()}.
+cursor_prev_value_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_search(cursor(), key()) -> {ok, value()} | {error, term()}.
-cursor_search(_Cursor, _Key) ->
+cursor_search(Cursor, Key) ->
+    ?ASYNC_NIF_CALL(fun cursor_search_nif/3, [Cursor, Key]).
+
+-spec cursor_search_nif(reference(), cursor(), key()) -> {ok, value()} | {error, term()}.
+cursor_search_nif(_AsyncRef, _Cursor, _Key) ->
     ?nif_stub.
 
 -spec cursor_search_near(cursor(), key()) -> {ok, value()} | {error, term()}.
-cursor_search_near(_Cursor, _Key) ->
+cursor_search_near(Cursor, Key) ->
+    ?ASYNC_NIF_CALL(fun cursor_search_near_nif/3, [Cursor, Key]).
+
+-spec cursor_search_near_nif(reference(), cursor(), key()) -> {ok, value()} | {error, term()}.
+cursor_search_near_nif(_AsyncRef, _Cursor, _Key) ->
     ?nif_stub.
 
 -spec cursor_reset(cursor()) -> ok | {error, term()}.
-cursor_reset(_Cursor) ->
+cursor_reset(Cursor) ->
+    ?ASYNC_NIF_CALL(fun cursor_reset_nif/2, [Cursor]).
+
+-spec cursor_reset_nif(reference(), cursor()) -> ok | {error, term()}.
+cursor_reset_nif(_AsyncRef, _Cursor) ->
     ?nif_stub.
 
 -spec cursor_insert(cursor(), key(), value()) -> ok | {error, term()}.
-cursor_insert(_Cursor, _Key, _Value) ->
+cursor_insert(Cursor, Key, Value) ->
+    ?ASYNC_NIF_CALL(fun cursor_insert_nif/4, [Cursor, Key, Value]).
+
+-spec cursor_insert_nif(reference(), cursor(), key(), value()) -> ok | {error, term()}.
+cursor_insert_nif(_AsyncRef, _Cursor, _Key, _Value) ->
     ?nif_stub.
 
 -spec cursor_update(cursor(), key(), value()) -> ok | {error, term()}.
-cursor_update(_Cursor, _Key, _Value) ->
+cursor_update(Cursor, Key, Value) ->
+    ?ASYNC_NIF_CALL(fun cursor_update_nif/4, [Cursor, Key, Value]).
+
+-spec cursor_update_nif(reference(), cursor(), key(), value()) -> ok | {error, term()}.
+cursor_update_nif(_AsyncRef, _Cursor, _Key, _Value) ->
     ?nif_stub.
 
 -spec cursor_remove(cursor(), key(), value()) -> ok | {error, term()}.
-cursor_remove(_Cursor, _Key, _Value) ->
+cursor_remove(Cursor, Key, Value) ->
+    ?ASYNC_NIF_CALL(fun cursor_remove_nif/4, [Cursor, Key, Value]).
+
+-spec cursor_remove_nif(reference(), cursor(), key(), value()) -> ok | {error, term()}.
+cursor_remove_nif(_AsyncRef, _Cursor, _Key, _Value) ->
     ?nif_stub.
 
 -type fold_keys_fun() :: fun((Key::binary(), any()) -> any()).