Add libar2simplified_init_context

Signed-off-by: Mattias Andrée <maandree@kth.se>

6 files changed, 441 insertions, 360 deletions

diff --git a/Makefile b/Makefile
index ab4c9ad..6827d97 100644
--- a/Makefile
+++ b/Makefile
@@ -22,6 +22,7 @@ OBJ =\
 	libar2simplified_encode.o\
 	libar2simplified_encode_hash.o\
 	libar2simplified_hash.o\
+	libar2simplified_init_context.o\
 	libar2simplified_recommendation.o
 
 HDR =\
diff --git a/libar2simplified.7 b/libar2simplified.7
index ef7584c..fa9219d 100644
--- a/libar2simplified.7
+++ b/libar2simplified.7
@@ -46,4 +46,5 @@ the parameters.
 .BR libar2simplified_encode (3),
 .BR libar2simplified_encode_hash (3),
 .BR libar2simplified_hash (3),
+.BR libar2simplified_init_context (3),
 .BR libar2simplified_recommendation (3)
diff --git a/libar2simplified.h b/libar2simplified.h
index e1233e2..0d005fb 100644
--- a/libar2simplified.h
+++ b/libar2simplified.h
@@ -162,4 +162,20 @@ int libar2simplified_hash(void *hash, void *msg, size_t msglen, struct libar2_ar
 LIBAR2_PUBLIC__ LIBAR2_NONNULL__(1, 2)
 char *libar2simplified_crypt(char *msg, const char *params, char *rv);
 
+/* Lower-level functions: */
+
+/**
+ * Initialises the context argument for `libar2_hash`,
+ * with all auto-erase options turned off
+ * 
+ * This function provides a dynamic memory management
+ * functions that erase memory before it is deallocated.
+ * It also also provides a multi-threading support using
+ * a thread pool.
+ * 
+ * @param  ctxp  Output parameter
+ */
+LIBAR2_PUBLIC__
+void libar2simplified_init_context(struct libar2_context *ctxp);
+
 #endif
diff --git a/libar2simplified_hash.c b/libar2simplified_hash.c
index e5765f5..20fb2c0 100644
--- a/libar2simplified_hash.c
+++ b/libar2simplified_hash.c
@@ -1,357 +1,5 @@
 /* See LICENSE file for copyright and license details. */
 #include "common.h"
-#include <pthread.h>
-#include <semaphore.h>
-
-
-struct user_data;
-
-struct thread_data {
-	size_t index;
-	struct user_data *master;
-	pthread_t thread;
-	sem_t semaphore;
-	int error;
-	void (*function)(void *data);
-	void *function_input;
-};
-
-struct user_data {
-	struct thread_data *threads;
-	size_t nthreads;
-	pthread_mutex_t mutex;
-	sem_t semaphore;
-	uint_least64_t *joined;
-	uint_least64_t resting[];
-};
-
-
-static void *
-alignedalloc(size_t num, size_t size, size_t extra, size_t alignment)
-{
-	void *ptr;
-	int err;
-	if (num > (SIZE_MAX - extra) / size) {
-		errno = ENOMEM;
-		return NULL;
-	}
-	if (alignment < sizeof(void *))
-		alignment = sizeof(void *);
-	err = posix_memalign(&ptr, alignment, num * size + extra);
-	if (err) {
-		errno = err;
-		return NULL;
-	} else {
-		return ptr;
-	}
-}
-
-
-static void *
-allocate(size_t num, size_t size, size_t alignment, struct libar2_context *ctx)
-{
-	size_t pad = (alignment - ((2 * sizeof(size_t)) & (alignment - 1))) & (alignment - 1);
-	char *ptr = alignedalloc(num, size, pad + 2 * sizeof(size_t), alignment);
-	if (ptr) {
-		ptr = &ptr[pad];
-		*(size_t *)ptr = pad;
-		ptr = &ptr[sizeof(size_t)];
-		*(size_t *)ptr = num * size;
-		ptr = &ptr[sizeof(size_t)];
-	}
-	(void) ctx;
-	return ptr;
-}
-
-
-static void
-deallocate(void *ptr, struct libar2_context *ctx)
-{
-	char *p = ptr;
-	p -= sizeof(size_t);
-	libar2_erase(ptr, *(size_t *)p);
-	p -= sizeof(size_t);
-	p -= *(size_t *)p;
-	free(p);
-	(void) ctx;
-}
-
-
-static void *
-thread_loop(void *data_)
-{
-	struct thread_data *data = data_;
-	int err;
-
-	for (;;) {
-		if (sem_wait(&data->semaphore)) {
-			if (errno == EINTR)
-				continue;
-			data->error = errno;
-			return NULL;
-		}
-
-		if (!data->function) {
-			data->error = ENOTRECOVERABLE;
-			return NULL;
-		}
-		data->function(data->function_input);
-
-		err = pthread_mutex_lock(&data->master->mutex);
-		if (err) {
-			data->error = err;
-			return NULL;
-		}
-		data->master->resting[data->index / 64] |= (uint_least64_t)1 << (data->index % 64);
-		pthread_mutex_unlock(&data->master->mutex);
-		if (sem_post(&data->master->semaphore)) {
-			data->error = errno;
-			return NULL;
-		}
-	}
-}
-
-
-static int
-run_thread(size_t index, void (*function)(void *arg), void *arg, struct libar2_context *ctx)
-{
-	struct user_data *data = ctx->user_data;
-	int err;
-
-	err = pthread_mutex_lock(&data->mutex);
-	if (err) {
-		errno = err;
-		return -1;
-	}
-	data->resting[index / 64] ^= (uint_least64_t)1 << (index % 64);
-	pthread_mutex_unlock(&data->mutex);
-
-	if (data->threads[index].error) {
-		errno = data->threads[index].error;
-		return -1;
-	}
-
-	data->threads[index].function = function;
-	data->threads[index].function_input = arg;
-	if (sem_post(&data->threads[index].semaphore))
-		return -1;
-
-	return 0;
-}
-
-
-static int
-destroy_thread_pool(struct libar2_context *ctx)
-{
-	struct user_data *data = ctx->user_data;
-	size_t i;
-	int ret = 0;
-	for (i = data->nthreads; i--;)
-		if (run_thread(i, pthread_exit, NULL, ctx))
-			return -1;
-	for (i = data->nthreads; i--;) {
-		pthread_join(data->threads[i].thread, NULL);
-		sem_destroy(&data->threads[i].semaphore);
-		if (data->threads[i].error)
-			ret = data->threads[i].error;
-	}
-	free(data->threads);
-	sem_destroy(&data->semaphore);
-	pthread_mutex_destroy(&data->mutex);
-	free(data);
-	return ret;
-}
-
-
-static int
-init_thread_pool(size_t desired, size_t *createdp, struct libar2_context *ctx)
-{
-	struct user_data *data;
-	int err;
-	size_t i, size;
-	long int nproc, nproc_limit;
-#ifdef __linux__
-	char path[sizeof("/sys/devices/system/cpu/cpu") + 3 * sizeof(nproc)];
-#endif
-#ifdef _SC_SEM_VALUE_MAX
-	long int semlimit;
-#endif
-
-	if (desired < 2) {
-		*createdp = 0;
-		return 0;
-	}
-
-	nproc = sysconf(_SC_NPROCESSORS_ONLN);
-#ifdef __linux__
-	if (nproc < 1) {
-		nproc_limit = desired > LONG_MAX ? LONG_MAX : (long int)desired;
-		for (nproc = 0; nproc < nproc_limit; nproc++) {
-			sprintf(path, "%s%li", "/sys/devices/system/cpu/cpu", nproc);
-			if (access(path, F_OK))
-				break;
-		}
-	}
-#endif
-	if (nproc < 1)
-		nproc = FALLBACK_NPROC;
-
-#ifdef _SC_SEM_VALUE_MAX
-	semlimit = sysconf(_SC_SEM_VALUE_MAX);
-	if (semlimit >= 1 && semlimit < nproc)
-		nproc = semlimit;
-#endif
-
-	if (nproc == 1) {
-		*createdp = 0;
-		return 0;
-	}
-
-	desired = (size_t)nproc < desired ? (size_t)nproc : desired;
-
-	if (desired > SIZE_MAX - 63 || (desired + 63) / 64 > SIZE_MAX / sizeof(uint_least64_t) / 2) {
-		errno = ENOMEM;
-		return -1;
-	}
-	size = (desired + 63) / 64;
-	size *= sizeof(uint_least64_t) * 2;
-	data = alignedalloc(1, offsetof(struct user_data, resting), size, ALIGNOF(struct user_data));
-	memset(data, 0, offsetof(struct user_data, resting) + size);
-	data->joined = &data->resting[(desired + 63) / 64];
-	ctx->user_data = data;
-
-	*createdp = data->nthreads = desired;
-
-	data->threads = alignedalloc(data->nthreads, sizeof(*data->threads), 0, ALIGNOF(struct thread_data));
-	if (!data->threads)
-		return -1;
-
-	err = pthread_mutex_init(&data->mutex, NULL);
-	if (err) {
-		free(data->threads);
-		return -1;
-	}
-	err = sem_init(&data->semaphore, 0, 0);
-	if (err) {
-		pthread_mutex_destroy(&data->mutex);
-		free(data->threads);
-		return -1;
-	}
-
-	for (i = 0; i < data->nthreads; i++) {
-		memset(&data->threads[i], 0, sizeof(data->threads[i]));
-		data->threads[i].master = data;
-		data->threads[i].index = i;
-		data->resting[i / 64] |= (uint_least64_t)1 << (i % 64);
-		if (sem_init(&data->threads[i].semaphore, 0, 0)) {
-			err = errno;
-			goto fail_post_sem;
-		}
-		err = pthread_create(&data->threads[i].thread, NULL, thread_loop, &data->threads[i]);
-		if (err) {
-			sem_destroy(&data->threads[i].semaphore);
-		fail_post_sem:
-			data->nthreads = i;
-			destroy_thread_pool(ctx);
-			errno = err;
-			return -1;
-		}
-	}
-
-	return 0;
-}
-
-
-#if defined(__GNUC__)
-__attribute__((__const__))
-#endif
-static size_t
-lb(uint_least64_t x)
-{
-	size_t r = 0;
-	while (x > 1) {
-		x >>= 1;
-		r += 1;
-	}
-	return r;
-}
-
-static size_t
-await_threads(size_t *indices, size_t n, size_t require, struct libar2_context *ctx)
-{
-	struct user_data *data = ctx->user_data;
-	size_t ret = 0, i;
-	uint_least64_t one;
-	int err;
-
-	memset(data->joined, 0, (data->nthreads + 63) / 64 * sizeof(*data->joined));
-
-	for (i = 0; i < data->nthreads; i += 64) {
-		for (;;) {
-			one = data->resting[i / 64];
-			one ^= data->joined[i / 64];
-			if (!one)
-				break;
-			one &= ~(one - 1);
-			data->joined[i / 64] |= one;
-			if (ret++ < n)
-				indices[ret - 1] = i + lb(one);
-		}
-	}
-
-	for (;;) {
-		if (ret < require) {
-			if (sem_wait(&data->semaphore)) {
-				if (errno == EINTR)
-					continue;
-				return 0;
-			}
-		} else if (sem_trywait(&data->semaphore)) {
-			if (errno == EAGAIN)
-				break;
-			else
-				return 0;
-		}
-
-		err = pthread_mutex_lock(&data->mutex);
-		if (err) {
-			errno = err;
-			return 0;
-		}
-		for (i = 0; i < data->nthreads; i += 64) {
-			one = data->resting[i / 64];
-			one ^= data->joined[i / 64];
-			if (!one)
-				continue;
-			one &= ~(one - 1);
-			data->joined[i / 64] |= one;
-			if (ret++ < n)
-				indices[ret - 1] = i + lb(one);
-			break;
-		}
-		pthread_mutex_unlock(&data->mutex);
-	}
-
-	return ret;
-}
-
-
-static size_t
-get_ready_threads(size_t *indices, size_t n, struct libar2_context *ctx)
-{
-	return await_threads(indices, n, 1, ctx);
-}
-
-
-static int
-join_thread_pool(struct libar2_context *ctx)
-{
-	struct user_data *data = ctx->user_data;
-	if (await_threads(NULL, 0, data->nthreads, ctx))
-		return 0;
-	destroy_thread_pool(ctx);
-	return -1;
-}
 
 
 int
@@ -360,15 +8,8 @@ libar2simplified_hash(void *hash, void *msg, size_t msglen, struct libar2_argon2
 	struct libar2_context ctx;
 	int ret;
 
-	memset(&ctx, 0, sizeof(ctx));
+	libar2simplified_init_context(&ctx);
 	ctx.autoerase_message = 1;
-	ctx.allocate = allocate;
-	ctx.deallocate = deallocate;
-	ctx.init_thread_pool = init_thread_pool;
-	ctx.get_ready_threads = get_ready_threads;
-	ctx.run_thread = run_thread;
-	ctx.join_thread_pool = join_thread_pool;
-	ctx.destroy_thread_pool = destroy_thread_pool;
 
 	ret = libar2_hash(hash, msg, msglen, params, &ctx);
 	if (ret)
diff --git a/libar2simplified_init_context.3 b/libar2simplified_init_context.3
new file mode 100644
index 0000000..c6abae7
--- /dev/null
+++ b/libar2simplified_init_context.3
@@ -0,0 +1,54 @@
+.TH LIBAR2SIMPLIFIED_INIT_CONTEXT 3 LIBAR2SIMPLIFIED
+.SH NAME
+libar2simplified_init_context - Create context for libar2_hash
+
+.SH SYNOPSIS
+.nf
+#include <libar2simplified.h>
+
+void libar2simplified_init_context(struct libar2_context *ctxp);
+.fi
+.PP
+Link with
+.IR "-lar2simplified -lrt -pthread" .
+
+.SH DESCRIPTION
+The
+.BR libar2simplified_init_context ()
+function initialises the context argument
+for the
+.BR libar2_hash (3)
+function, provided via the
+.I ctxp
+parameter, with all auto-erase options
+turned off.
+.PP
+This function provides a dynamic memory
+management functions that erase memory
+before it is deallocated. It also also
+provides a multi-threading support using
+a thread pool.
+.PP
+This function is used internally by the
+.BR libar2simplified (7)
+library, but cannot be used with any
+function provided by the library, it can
+however be used together with the
+.BR libar2 (7)
+library, specifically it is designed for the
+.BR libar2_hash (3)
+function, but can also be used with the
+.BR libar2_decode_params (3)
+function.
+
+.SH RETURN VALUES
+None.
+
+.SH ERRORS
+The
+.BR libar2simplified_recommendation ()
+function cannot fail.
+
+.SH SEE ALSO
+.BR libar2simplified (7),
+.BR libar2_hash (3)
diff --git a/libar2simplified_init_context.c b/libar2simplified_init_context.c
new file mode 100644
index 0000000..c7f8b69
--- /dev/null
+++ b/libar2simplified_init_context.c
@@ -0,0 +1,368 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#include <pthread.h>
+#include <semaphore.h>
+
+
+struct user_data;
+
+struct thread_data {
+	size_t index;
+	struct user_data *master;
+	pthread_t thread;
+	sem_t semaphore;
+	int error;
+	void (*function)(void *data);
+	void *function_input;
+};
+
+struct user_data {
+	struct thread_data *threads;
+	size_t nthreads;
+	pthread_mutex_t mutex;
+	sem_t semaphore;
+	uint_least64_t *joined;
+	uint_least64_t resting[];
+};
+
+
+static void *
+alignedalloc(size_t num, size_t size, size_t extra, size_t alignment)
+{
+	void *ptr;
+	int err;
+	if (num > (SIZE_MAX - extra) / size) {
+		errno = ENOMEM;
+		return NULL;
+	}
+	if (alignment < sizeof(void *))
+		alignment = sizeof(void *);
+	err = posix_memalign(&ptr, alignment, num * size + extra);
+	if (err) {
+		errno = err;
+		return NULL;
+	} else {
+		return ptr;
+	}
+}
+
+
+static void *
+allocate(size_t num, size_t size, size_t alignment, struct libar2_context *ctx)
+{
+	size_t pad = (alignment - ((2 * sizeof(size_t)) & (alignment - 1))) & (alignment - 1);
+	char *ptr = alignedalloc(num, size, pad + 2 * sizeof(size_t), alignment);
+	if (ptr) {
+		ptr = &ptr[pad];
+		*(size_t *)ptr = pad;
+		ptr = &ptr[sizeof(size_t)];
+		*(size_t *)ptr = num * size;
+		ptr = &ptr[sizeof(size_t)];
+	}
+	(void) ctx;
+	return ptr;
+}
+
+
+static void
+deallocate(void *ptr, struct libar2_context *ctx)
+{
+	char *p = ptr;
+	p -= sizeof(size_t);
+	libar2_erase(ptr, *(size_t *)p);
+	p -= sizeof(size_t);
+	p -= *(size_t *)p;
+	free(p);
+	(void) ctx;
+}
+
+
+static void *
+thread_loop(void *data_)
+{
+	struct thread_data *data = data_;
+	int err;
+
+	for (;;) {
+		if (sem_wait(&data->semaphore)) {
+			if (errno == EINTR)
+				continue;
+			data->error = errno;
+			return NULL;
+		}
+
+		if (!data->function) {
+			data->error = ENOTRECOVERABLE;
+			return NULL;
+		}
+		data->function(data->function_input);
+
+		err = pthread_mutex_lock(&data->master->mutex);
+		if (err) {
+			data->error = err;
+			return NULL;
+		}
+		data->master->resting[data->index / 64] |= (uint_least64_t)1 << (data->index % 64);
+		pthread_mutex_unlock(&data->master->mutex);
+		if (sem_post(&data->master->semaphore)) {
+			data->error = errno;
+			return NULL;
+		}
+	}
+}
+
+
+static int
+run_thread(size_t index, void (*function)(void *arg), void *arg, struct libar2_context *ctx)
+{
+	struct user_data *data = ctx->user_data;
+	int err;
+
+	err = pthread_mutex_lock(&data->mutex);
+	if (err) {
+		errno = err;
+		return -1;
+	}
+	data->resting[index / 64] ^= (uint_least64_t)1 << (index % 64);
+	pthread_mutex_unlock(&data->mutex);
+
+	if (data->threads[index].error) {
+		errno = data->threads[index].error;
+		return -1;
+	}
+
+	data->threads[index].function = function;
+	data->threads[index].function_input = arg;
+	if (sem_post(&data->threads[index].semaphore))
+		return -1;
+
+	return 0;
+}
+
+
+static int
+destroy_thread_pool(struct libar2_context *ctx)
+{
+	struct user_data *data = ctx->user_data;
+	size_t i;
+	int ret = 0;
+	for (i = data->nthreads; i--;)
+		if (run_thread(i, pthread_exit, NULL, ctx))
+			return -1;
+	for (i = data->nthreads; i--;) {
+		pthread_join(data->threads[i].thread, NULL);
+		sem_destroy(&data->threads[i].semaphore);
+		if (data->threads[i].error)
+			ret = data->threads[i].error;
+	}
+	free(data->threads);
+	sem_destroy(&data->semaphore);
+	pthread_mutex_destroy(&data->mutex);
+	free(data);
+	return ret;
+}
+
+
+static int
+init_thread_pool(size_t desired, size_t *createdp, struct libar2_context *ctx)
+{
+	struct user_data *data;
+	int err;
+	size_t i, size;
+	long int nproc, nproc_limit;
+#ifdef __linux__
+	char path[sizeof("/sys/devices/system/cpu/cpu") + 3 * sizeof(nproc)];
+#endif
+#ifdef _SC_SEM_VALUE_MAX
+	long int semlimit;
+#endif
+
+	if (desired < 2) {
+		*createdp = 0;
+		return 0;
+	}
+
+	nproc = sysconf(_SC_NPROCESSORS_ONLN);
+#ifdef __linux__
+	if (nproc < 1) {
+		nproc_limit = desired > LONG_MAX ? LONG_MAX : (long int)desired;
+		for (nproc = 0; nproc < nproc_limit; nproc++) {
+			sprintf(path, "%s%li", "/sys/devices/system/cpu/cpu", nproc);
+			if (access(path, F_OK))
+				break;
+		}
+	}
+#endif
+	if (nproc < 1)
+		nproc = FALLBACK_NPROC;
+
+#ifdef _SC_SEM_VALUE_MAX
+	semlimit = sysconf(_SC_SEM_VALUE_MAX);
+	if (semlimit >= 1 && semlimit < nproc)
+		nproc = semlimit;
+#endif
+
+	if (nproc == 1) {
+		*createdp = 0;
+		return 0;
+	}
+
+	desired = (size_t)nproc < desired ? (size_t)nproc : desired;
+
+	if (desired > SIZE_MAX - 63 || (desired + 63) / 64 > SIZE_MAX / sizeof(uint_least64_t) / 2) {
+		errno = ENOMEM;
+		return -1;
+	}
+	size = (desired + 63) / 64;
+	size *= sizeof(uint_least64_t) * 2;
+	data = alignedalloc(1, offsetof(struct user_data, resting), size, ALIGNOF(struct user_data));
+	memset(data, 0, offsetof(struct user_data, resting) + size);
+	data->joined = &data->resting[(desired + 63) / 64];
+	ctx->user_data = data;
+
+	*createdp = data->nthreads = desired;
+
+	data->threads = alignedalloc(data->nthreads, sizeof(*data->threads), 0, ALIGNOF(struct thread_data));
+	if (!data->threads)
+		return -1;
+
+	err = pthread_mutex_init(&data->mutex, NULL);
+	if (err) {
+		free(data->threads);
+		return -1;
+	}
+	err = sem_init(&data->semaphore, 0, 0);
+	if (err) {
+		pthread_mutex_destroy(&data->mutex);
+		free(data->threads);
+		return -1;
+	}
+
+	for (i = 0; i < data->nthreads; i++) {
+		memset(&data->threads[i], 0, sizeof(data->threads[i]));
+		data->threads[i].master = data;
+		data->threads[i].index = i;
+		data->resting[i / 64] |= (uint_least64_t)1 << (i % 64);
+		if (sem_init(&data->threads[i].semaphore, 0, 0)) {
+			err = errno;
+			goto fail_post_sem;
+		}
+		err = pthread_create(&data->threads[i].thread, NULL, thread_loop, &data->threads[i]);
+		if (err) {
+			sem_destroy(&data->threads[i].semaphore);
+		fail_post_sem:
+			data->nthreads = i;
+			destroy_thread_pool(ctx);
+			errno = err;
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+
+#if defined(__GNUC__)
+__attribute__((__const__))
+#endif
+static size_t
+lb(uint_least64_t x)
+{
+	size_t r = 0;
+	while (x > 1) {
+		x >>= 1;
+		r += 1;
+	}
+	return r;
+}
+
+static size_t
+await_threads(size_t *indices, size_t n, size_t require, struct libar2_context *ctx)
+{
+	struct user_data *data = ctx->user_data;
+	size_t ret = 0, i;
+	uint_least64_t one;
+	int err;
+
+	memset(data->joined, 0, (data->nthreads + 63) / 64 * sizeof(*data->joined));
+
+	for (i = 0; i < data->nthreads; i += 64) {
+		for (;;) {
+			one = data->resting[i / 64];
+			one ^= data->joined[i / 64];
+			if (!one)
+				break;
+			one &= ~(one - 1);
+			data->joined[i / 64] |= one;
+			if (ret++ < n)
+				indices[ret - 1] = i + lb(one);
+		}
+	}
+
+	for (;;) {
+		if (ret < require) {
+			if (sem_wait(&data->semaphore)) {
+				if (errno == EINTR)
+					continue;
+				return 0;
+			}
+		} else if (sem_trywait(&data->semaphore)) {
+			if (errno == EAGAIN)
+				break;
+			else
+				return 0;
+		}
+
+		err = pthread_mutex_lock(&data->mutex);
+		if (err) {
+			errno = err;
+			return 0;
+		}
+		for (i = 0; i < data->nthreads; i += 64) {
+			one = data->resting[i / 64];
+			one ^= data->joined[i / 64];
+			if (!one)
+				continue;
+			one &= ~(one - 1);
+			data->joined[i / 64] |= one;
+			if (ret++ < n)
+				indices[ret - 1] = i + lb(one);
+			break;
+		}
+		pthread_mutex_unlock(&data->mutex);
+	}
+
+	return ret;
+}
+
+
+static size_t
+get_ready_threads(size_t *indices, size_t n, struct libar2_context *ctx)
+{
+	return await_threads(indices, n, 1, ctx);
+}
+
+
+static int
+join_thread_pool(struct libar2_context *ctx)
+{
+	struct user_data *data = ctx->user_data;
+	if (await_threads(NULL, 0, data->nthreads, ctx))
+		return 0;
+	destroy_thread_pool(ctx);
+	return -1;
+}
+
+
+void
+libar2simplified_init_context(struct libar2_context *ctxp)
+{
+	memset(ctxp, 0, sizeof(*ctxp));
+	ctxp->allocate = allocate;
+	ctxp->deallocate = deallocate;
+	ctxp->init_thread_pool = init_thread_pool;
+	ctxp->get_ready_threads = get_ready_threads;
+	ctxp->run_thread = run_thread;
+	ctxp->join_thread_pool = join_thread_pool;
+	ctxp->destroy_thread_pool = destroy_thread_pool;
+}