1 files changed, 336 insertions, 514 deletions

diff --git a/lib/async_req/async_sock.c b/lib/async_req/async_sock.c
index 02ae880683..1f48697f26 100644
--- a/lib/async_req/async_sock.c
+++ b/lib/async_req/async_sock.c
@@ -22,6 +22,7 @@
 #include "lib/tevent/tevent.h"
 #include "lib/async_req/async_req.h"
 #include "lib/async_req/async_sock.h"
+#include "lib/util/tevent_unix.h"
 #include <fcntl.h>
 
 #ifndef TALLOC_FREE
@@ -29,72 +30,6 @@
 #endif
 
 /**
- * Discriminator for async_syscall_state
- */
-enum async_syscall_type {
-	ASYNC_SYSCALL_SEND,
-	ASYNC_SYSCALL_SENDALL,
-	ASYNC_SYSCALL_RECV,
-	ASYNC_SYSCALL_RECVALL,
-	ASYNC_SYSCALL_CONNECT
-};
-
-/**
- * Holder for syscall arguments and the result
- */
-
-struct async_syscall_state {
-	enum async_syscall_type syscall_type;
-	struct tevent_fd *fde;
-
-	union {
-		struct param_send {
-			int fd;
-			const void *buffer;
-			size_t length;
-			int flags;
-		} param_send;
-		struct param_sendall {
-			int fd;
-			const void *buffer;
-			size_t length;
-			int flags;
-			size_t sent;
-		} param_sendall;
-		struct param_recv {
-			int fd;
-			void *buffer;
-			size_t length;
-			int flags;
-		} param_recv;
-		struct param_recvall {
-			int fd;
-			void *buffer;
-			size_t length;
-			int flags;
-			size_t received;
-		} param_recvall;
-		struct param_connect {
-			/**
-			 * connect needs to be done on a nonblocking
-			 * socket. Keep the old flags around
-			 */
-			long old_sockflags;
-			int fd;
-			const struct sockaddr *address;
-			socklen_t address_len;
-		} param_connect;
-	} param;
-
-	union {
-		ssize_t result_ssize_t;
-		size_t result_size_t;
-		int result_int;
-	} result;
-	int sys_errno;
-};
-
-/**
  * @brief Map async_req states to unix-style errnos
  * @param[in]  req	The async req to get the state from
  * @param[out] err	Pointer to take the unix-style errno
@@ -143,470 +78,138 @@ int async_req_simple_recv_errno(struct async_req *req)
 	return 0;
 }
 
-/**
- * @brief Create a new async syscall req
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] type	Which syscall will this be
- * @param[in] pstate	Where to put the newly created private_data state
- * @retval The new request
- *
- * This is a helper function to prepare a new struct async_req with an
- * associated struct async_syscall_state. The async_syscall_state will be put
- * into the async_req as private_data.
- */
-
-static struct async_req *async_syscall_new(TALLOC_CTX *mem_ctx,
-					   struct tevent_context *ev,
-					   enum async_syscall_type type,
-					   struct async_syscall_state **pstate)
-{
-	struct async_req *result;
-	struct async_syscall_state *state;
-
-	if (!async_req_setup(mem_ctx, &result, &state,
-			     struct async_syscall_state)) {
-		return NULL;
-	}
-	state->syscall_type = type;
-
-	result->private_data = state;
-
-	*pstate = state;
+struct async_send_state {
+	int fd;
+	const void *buf;
+	size_t len;
+	int flags;
+	ssize_t sent;
+};
 
-	return result;
-}
+static void async_send_handler(struct tevent_context *ev,
+			       struct tevent_fd *fde,
+			       uint16_t flags, void *private_data);
 
-/**
- * @brief Create a new async syscall req based on a fd
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] type	Which syscall will this be
- * @param[in] fd	The file descriptor we work on
- * @param[in] fde_flags TEVENT_FD_READ/WRITE -- what are we interested in?
- * @param[in] fde_cb	The callback function for the file descriptor event
- * @param[in] pstate	Where to put the newly created private_data state
- * @retval The new request
- *
- * This is a helper function to prepare a new struct async_req with an
- * associated struct async_syscall_state and an associated file descriptor
- * event.
- */
-
-static struct async_req *async_fde_syscall_new(
-	TALLOC_CTX *mem_ctx,
-	struct tevent_context *ev,
-	enum async_syscall_type type,
-	int fd,
-	uint16_t fde_flags,
-	void (*fde_cb)(struct tevent_context *ev,
-		       struct tevent_fd *fde, uint16_t flags,
-		       void *priv),
-	struct async_syscall_state **pstate)
+struct tevent_req *async_send_send(TALLOC_CTX *mem_ctx,
+				   struct tevent_context *ev,
+				   int fd, const void *buf, size_t len,
+				   int flags)
 {
-	struct async_req *result;
-	struct async_syscall_state *state;
+	struct tevent_req *result;
+	struct async_send_state *state;
+	struct tevent_fd *fde;
 
-	result = async_syscall_new(mem_ctx, ev, type, &state);
+	result = tevent_req_create(mem_ctx, &state, struct async_send_state);
 	if (result == NULL) {
-		return NULL;
+		return result;
 	}
+	state->fd = fd;
+	state->buf = buf;
+	state->len = len;
+	state->flags = flags;
 
-	state->fde = tevent_add_fd(ev, state, fd, fde_flags, fde_cb, result);
-	if (state->fde == NULL) {
+	fde = tevent_add_fd(ev, state, fd, TEVENT_FD_WRITE, async_send_handler,
+			    result);
+	if (fde == NULL) {
 		TALLOC_FREE(result);
 		return NULL;
 	}
-	*pstate = state;
 	return result;
 }
 
-/**
- * Retrieve a ssize_t typed result from an async syscall
- * @param[in] req	The syscall that has just finished
- * @param[out] perrno	Where to put the syscall's errno
- * @retval The return value from the asynchronously called syscall
- */
-
-ssize_t async_syscall_result_ssize_t(struct async_req *req, int *perrno)
-{
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-
-	*perrno = state->sys_errno;
-	return state->result.result_ssize_t;
-}
-
-/**
- * Retrieve a size_t typed result from an async syscall
- * @param[in] req	The syscall that has just finished
- * @param[out] perrno	Where to put the syscall's errno
- * @retval The return value from the asynchronously called syscall
- */
-
-size_t async_syscall_result_size_t(struct async_req *req, int *perrno)
-{
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-
-	*perrno = state->sys_errno;
-	return state->result.result_size_t;
-}
-
-/**
- * Retrieve a int typed result from an async syscall
- * @param[in] req	The syscall that has just finished
- * @param[out] perrno	Where to put the syscall's errno
- * @retval The return value from the asynchronously called syscall
- */
-
-int async_syscall_result_int(struct async_req *req, int *perrno)
-{
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-
-	*perrno = state->sys_errno;
-	return state->result.result_int;
-}
-
-/**
- * fde event handler for the "send" syscall
- * @param[in] ev	The event context that sent us here
- * @param[in] fde	The file descriptor event associated with the send
- * @param[in] flags	Can only be TEVENT_FD_WRITE here
- * @param[in] priv	private data, "struct async_req *" in this case
- */
-
-static void async_send_callback(struct tevent_context *ev,
-				struct tevent_fd *fde, uint16_t flags,
-				void *priv)
+static void async_send_handler(struct tevent_context *ev,
+			       struct tevent_fd *fde,
+			       uint16_t flags, void *private_data)
 {
-	struct async_req *req = talloc_get_type_abort(
-		priv, struct async_req);
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	struct param_send *p = &state->param.param_send;
-
-	if (state->syscall_type != ASYNC_SYSCALL_SEND) {
-		async_req_error(req, EIO);
+	struct tevent_req *req = talloc_get_type_abort(
+		private_data, struct tevent_req);
+	struct async_send_state *state = talloc_get_type_abort(
+		req->private_state, struct async_send_state);
+
+	state->sent = send(state->fd, state->buf, state->len, state->flags);
+	if (state->sent == -1) {
+		tevent_req_error(req, errno);
 		return;
 	}
-
-	state->result.result_ssize_t = send(p->fd, p->buffer, p->length,
-					    p->flags);
-	state->sys_errno = errno;
-
-	TALLOC_FREE(state->fde);
-
-	async_req_done(req);
+	tevent_req_done(req);
 }
 
-/**
- * Async version of send(2)
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] fd	The socket to send to
- * @param[in] buffer	The buffer to send
- * @param[in] length	How many bytes to send
- * @param[in] flags	flags passed to send(2)
- *
- * This function is a direct counterpart of send(2)
- */
-
-struct async_req *async_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			     int fd, const void *buffer, size_t length,
-			     int flags)
+ssize_t async_send_recv(struct tevent_req *req, int *perrno)
 {
-	struct async_req *result;
-	struct async_syscall_state *state;
+	struct async_send_state *state = talloc_get_type_abort(
+		req->private_state, struct async_send_state);
 
-	result = async_fde_syscall_new(
-		mem_ctx, ev, ASYNC_SYSCALL_SEND,
-		fd, TEVENT_FD_WRITE, async_send_callback,
-		&state);
-	if (result == NULL) {
-		return NULL;
+	if (tevent_req_is_unix_error(req, perrno)) {
+		return -1;
 	}
-
-	state->param.param_send.fd = fd;
-	state->param.param_send.buffer = buffer;
-	state->param.param_send.length = length;
-	state->param.param_send.flags = flags;
-
-	return result;
+	return state->sent;
 }
 
-/**
- * fde event handler for the "sendall" syscall group
- * @param[in] ev	The event context that sent us here
- * @param[in] fde	The file descriptor event associated with the send
- * @param[in] flags	Can only be TEVENT_FD_WRITE here
- * @param[in] priv	private data, "struct async_req *" in this case
- */
-
-static void async_sendall_callback(struct tevent_context *ev,
-				   struct tevent_fd *fde, uint16_t flags,
-				   void *priv)
-{
-	struct async_req *req = talloc_get_type_abort(
-		priv, struct async_req);
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	struct param_sendall *p = &state->param.param_sendall;
-
-	if (state->syscall_type != ASYNC_SYSCALL_SENDALL) {
-		async_req_error(req, EIO);
-		return;
-	}
-
-	state->result.result_ssize_t = send(p->fd,
-					    (const char *)p->buffer + p->sent,
-					    p->length - p->sent, p->flags);
-	state->sys_errno = errno;
-
-	if (state->result.result_ssize_t == -1) {
-		async_req_error(req, state->sys_errno);
-		return;
-	}
-
-	if (state->result.result_ssize_t == 0) {
-		async_req_error(req, EOF);
-		return;
-	}
-
-	p->sent += state->result.result_ssize_t;
-	if (p->sent > p->length) {
-		async_req_error(req, EIO);
-		return;
-	}
+struct async_recv_state {
+	int fd;
+	void *buf;
+	size_t len;
+	int flags;
+	ssize_t received;
+};
 
-	if (p->sent == p->length) {
-		TALLOC_FREE(state->fde);
-		async_req_done(req);
-	}
-}
+static void async_recv_handler(struct tevent_context *ev,
+			       struct tevent_fd *fde,
+			       uint16_t flags, void *private_data);
 
-/**
- * @brief Send all bytes to a socket
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] fd	The socket to send to
- * @param[in] buffer	The buffer to send
- * @param[in] length	How many bytes to send
- * @param[in] flags	flags passed to send(2)
- *
- * async_sendall calls send(2) as long as it is necessary to send all of the
- * "length" bytes
- */
-
-struct async_req *sendall_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			       int fd, const void *buffer, size_t length,
-			       int flags)
+struct tevent_req *async_recv_send(TALLOC_CTX *mem_ctx,
+				   struct tevent_context *ev,
+				   int fd, void *buf, size_t len, int flags)
 {
-	struct async_req *result;
-	struct async_syscall_state *state;
+	struct tevent_req *result;
+	struct async_recv_state *state;
+	struct tevent_fd *fde;
 
-	result = async_fde_syscall_new(
-		mem_ctx, ev, ASYNC_SYSCALL_SENDALL,
-		fd, TEVENT_FD_WRITE, async_sendall_callback,
-		&state);
+	result = tevent_req_create(mem_ctx, &state, struct async_recv_state);
 	if (result == NULL) {
-		return NULL;
-	}
-
-	state->param.param_sendall.fd = fd;
-	state->param.param_sendall.buffer = buffer;
-	state->param.param_sendall.length = length;
-	state->param.param_sendall.flags = flags;
-	state->param.param_sendall.sent = 0;
-
-	return result;
-}
-
-ssize_t sendall_recv(struct async_req *req, int *perr)
-{
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	int err;
-
-	err = async_req_simple_recv_errno(req);
-
-	if (err != 0) {
-		*perr = err;
-		return -1;
-	}
-
-	return state->result.result_ssize_t;
-}
-
-/**
- * fde event handler for the "recv" syscall
- * @param[in] ev	The event context that sent us here
- * @param[in] fde	The file descriptor event associated with the recv
- * @param[in] flags	Can only be TEVENT_FD_READ here
- * @param[in] priv	private data, "struct async_req *" in this case
- */
-
-static void async_recv_callback(struct tevent_context *ev,
-				struct tevent_fd *fde, uint16_t flags,
-				void *priv)
-{
-	struct async_req *req = talloc_get_type_abort(
-		priv, struct async_req);
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	struct param_recv *p = &state->param.param_recv;
-
-	if (state->syscall_type != ASYNC_SYSCALL_RECV) {
-		async_req_error(req, EIO);
-		return;
+		return result;
 	}
+	state->fd = fd;
+	state->buf = buf;
+	state->len = len;
+	state->flags = flags;
 
-	state->result.result_ssize_t = recv(p->fd, p->buffer, p->length,
-					    p->flags);
-	state->sys_errno = errno;
-
-	TALLOC_FREE(state->fde);
-
-	async_req_done(req);
-}
-
-/**
- * Async version of recv(2)
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] fd	The socket to recv from
- * @param[in] buffer	The buffer to recv into
- * @param[in] length	How many bytes to recv
- * @param[in] flags	flags passed to recv(2)
- *
- * This function is a direct counterpart of recv(2)
- */
-
-struct async_req *async_recv(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			     int fd, void *buffer, size_t length,
-			     int flags)
-{
-	struct async_req *result;
-	struct async_syscall_state *state;
-
-	result = async_fde_syscall_new(
-		mem_ctx, ev, ASYNC_SYSCALL_RECV,
-		fd, TEVENT_FD_READ, async_recv_callback,
-		&state);
-
-	if (result == NULL) {
+	fde = tevent_add_fd(ev, state, fd, TEVENT_FD_READ, async_recv_handler,
+			    result);
+	if (fde == NULL) {
+		TALLOC_FREE(result);
 		return NULL;
 	}
-
-	state->param.param_recv.fd = fd;
-	state->param.param_recv.buffer = buffer;
-	state->param.param_recv.length = length;
-	state->param.param_recv.flags = flags;
-
 	return result;
 }
 
-/**
- * fde event handler for the "recvall" syscall group
- * @param[in] ev	The event context that sent us here
- * @param[in] fde	The file descriptor event associated with the recv
- * @param[in] flags	Can only be TEVENT_FD_READ here
- * @param[in] priv	private data, "struct async_req *" in this case
- */
-
-static void async_recvall_callback(struct tevent_context *ev,
-				   struct tevent_fd *fde, uint16_t flags,
-				   void *priv)
+static void async_recv_handler(struct tevent_context *ev,
+			       struct tevent_fd *fde,
+			       uint16_t flags, void *private_data)
 {
-	struct async_req *req = talloc_get_type_abort(
-		priv, struct async_req);
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	struct param_recvall *p = &state->param.param_recvall;
-
-	if (state->syscall_type != ASYNC_SYSCALL_RECVALL) {
-		async_req_error(req, EIO);
-		return;
-	}
-
-	state->result.result_ssize_t = recv(p->fd,
-					    (char *)p->buffer + p->received,
-					    p->length - p->received, p->flags);
-	state->sys_errno = errno;
-
-	if (state->result.result_ssize_t == -1) {
-		async_req_error(req, state->sys_errno);
+	struct tevent_req *req = talloc_get_type_abort(
+		private_data, struct tevent_req);
+	struct async_recv_state *state = talloc_get_type_abort(
+		req->private_state, struct async_recv_state);
+
+	state->received = recv(state->fd, state->buf, state->len,
+			       state->flags);
+	if (state->received == -1) {
+		tevent_req_error(req, errno);
 		return;
 	}
-
-	if (state->result.result_ssize_t == 0) {
-		async_req_error(req, EIO);
-		return;
-	}
-
-	p->received += state->result.result_ssize_t;
-	if (p->received > p->length) {
-		async_req_error(req, EIO);
-		return;
-	}
-
-	if (p->received == p->length) {
-		TALLOC_FREE(state->fde);
-		async_req_done(req);
-	}
-}
-
-/**
- * Receive a specified number of bytes from a socket
- * @param[in] mem_ctx	The memory context to hang the result off
- * @param[in] ev	The event context to work from
- * @param[in] fd	The socket to recv from
- * @param[in] buffer	The buffer to recv into
- * @param[in] length	How many bytes to recv
- * @param[in] flags	flags passed to recv(2)
- *
- * async_recvall will call recv(2) until "length" bytes are received
- */
-
-struct async_req *recvall_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			       int fd, void *buffer, size_t length,
-			       int flags)
-{
-	struct async_req *result;
-	struct async_syscall_state *state;
-
-	result = async_fde_syscall_new(
-		mem_ctx, ev, ASYNC_SYSCALL_RECVALL,
-		fd, TEVENT_FD_READ, async_recvall_callback,
-		&state);
-	if (result == NULL) {
-		return NULL;
-	}
-
-	state->param.param_recvall.fd = fd;
-	state->param.param_recvall.buffer = buffer;
-	state->param.param_recvall.length = length;
-	state->param.param_recvall.flags = flags;
-	state->param.param_recvall.received = 0;
-
-	return result;
+	tevent_req_done(req);
 }
 
-ssize_t recvall_recv(struct async_req *req, int *perr)
+ssize_t async_recv_recv(struct tevent_req *req, int *perrno)
 {
-	struct async_syscall_state *state = talloc_get_type_abort(
-		req->private_data, struct async_syscall_state);
-	int err;
+	struct async_recv_state *state = talloc_get_type_abort(
+		req->private_state, struct async_recv_state);
 
-	err = async_req_simple_recv_errno(req);
-
-	if (err != 0) {
-		*perr = err;
+	if (tevent_req_is_unix_error(req, perrno)) {
 		return -1;
 	}
-
-	return state->result.result_ssize_t;
+	return state->received;
 }
 
 struct async_connect_state {
@@ -633,17 +236,18 @@ static void async_connect_connected(struct tevent_context *ev,
  * connect in an async state. This will be reset when the request is finished.
  */
 
-struct async_req *async_connect_send(TALLOC_CTX *mem_ctx,
-				     struct tevent_context *ev,
-				     int fd, const struct sockaddr *address,
-				     socklen_t address_len)
+struct tevent_req *async_connect_send(TALLOC_CTX *mem_ctx,
+				      struct tevent_context *ev,
+				      int fd, const struct sockaddr *address,
+				      socklen_t address_len)
 {
-	struct async_req *result;
+	struct tevent_req *result;
 	struct async_connect_state *state;
 	struct tevent_fd *fde;
 
-	if (!async_req_setup(mem_ctx, &result, &state,
-			     struct async_connect_state)) {
+	result = tevent_req_create(
+		mem_ctx, &state, struct async_connect_state);
+	if (result == NULL) {
 		return NULL;
 	}
 
@@ -664,8 +268,8 @@ struct async_req *async_connect_send(TALLOC_CTX *mem_ctx,
 
 	state->result = connect(fd, address, address_len);
 	if (state->result == 0) {
-		state->sys_errno = 0;
-		goto post_status;
+		tevent_req_done(result);
+		goto done;
 	}
 
 	/**
@@ -680,6 +284,7 @@ struct async_req *async_connect_send(TALLOC_CTX *mem_ctx,
 	      errno == EISCONN ||
 #endif
 	      errno == EAGAIN || errno == EINTR)) {
+		state->sys_errno = errno;
 		goto post_errno;
 	}
 
@@ -687,21 +292,15 @@ struct async_req *async_connect_send(TALLOC_CTX *mem_ctx,
 			   async_connect_connected, result);
 	if (fde == NULL) {
 		state->sys_errno = ENOMEM;
-		goto post_status;
+		goto post_errno;
 	}
 	return result;
 
  post_errno:
-	state->sys_errno = errno;
- post_status:
+	tevent_req_error(result, state->sys_errno);
+ done:
 	fcntl(fd, F_SETFL, state->old_sockflags);
-	if (!async_post_error(result, ev, state->sys_errno)) {
-		goto fail;
-	}
-	return result;
- fail:
-	TALLOC_FREE(result);
-	return NULL;
+	return tevent_req_post(result, ev);
 }
 
 /**
@@ -716,10 +315,10 @@ static void async_connect_connected(struct tevent_context *ev,
 				    struct tevent_fd *fde, uint16_t flags,
 				    void *priv)
 {
-	struct async_req *req = talloc_get_type_abort(
-		priv, struct async_req);
+	struct tevent_req *req = talloc_get_type_abort(
+		priv, struct tevent_req);
 	struct async_connect_state *state = talloc_get_type_abort(
-		req->private_data, struct async_connect_state);
+		req->private_state, struct async_connect_state);
 
 	TALLOC_FREE(fde);
 
@@ -743,27 +342,27 @@ static void async_connect_connected(struct tevent_context *ev,
 		DEBUG(10, ("connect returned %s\n", strerror(errno)));
 
 		fcntl(state->fd, F_SETFL, state->old_sockflags);
-		async_req_error(req, state->sys_errno);
+		tevent_req_error(req, state->sys_errno);
 		return;
 	}
 
 	state->sys_errno = 0;
-	async_req_done(req);
+	tevent_req_done(req);
 }
 
-int async_connect_recv(struct async_req *req, int *perrno)
+int async_connect_recv(struct tevent_req *req, int *perrno)
 {
 	struct async_connect_state *state = talloc_get_type_abort(
-		req->private_data, struct async_connect_state);
+		req->private_state, struct async_connect_state);
 	int err;
 
 	fcntl(state->fd, F_SETFL, state->old_sockflags);
 
-
-	if (async_req_is_errno(req, &err)) {
+	if (tevent_req_is_unix_error(req, &err)) {
 		*perrno = err;
 		return -1;
 	}
+
 	if (state->sys_errno == 0) {
 		return 0;
 	}
@@ -771,3 +370,226 @@ int async_connect_recv(struct async_req *req, int *perrno)
 	*perrno = state->sys_errno;
 	return -1;
 }
+
+struct writev_state {
+	struct tevent_context *ev;
+	int fd;
+	struct iovec *iov;
+	int count;
+	size_t total_size;
+};
+
+static void writev_handler(struct tevent_context *ev, struct tevent_fd *fde,
+			   uint16_t flags, void *private_data);
+
+struct tevent_req *writev_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
+			       int fd, struct iovec *iov, int count)
+{
+	struct tevent_req *result;
+	struct writev_state *state;
+	struct tevent_fd *fde;
+
+	result = tevent_req_create(mem_ctx, &state, struct writev_state);
+	if (result == NULL) {
+		return NULL;
+	}
+	state->ev = ev;
+	state->fd = fd;
+	state->total_size = 0;
+	state->count = count;
+	state->iov = (struct iovec *)talloc_memdup(
+		state, iov, sizeof(struct iovec) * count);
+	if (state->iov == NULL) {
+		goto fail;
+	}
+
+	fde = tevent_add_fd(ev, state, fd, TEVENT_FD_WRITE, writev_handler,
+			    result);
+	if (fde == NULL) {
+		goto fail;
+	}
+	return result;
+
+ fail:
+	TALLOC_FREE(result);
+	return NULL;
+}
+
+static void writev_handler(struct tevent_context *ev, struct tevent_fd *fde,
+			   uint16_t flags, void *private_data)
+{
+	struct tevent_req *req = talloc_get_type_abort(
+		private_data, struct tevent_req);
+	struct writev_state *state = talloc_get_type_abort(
+		req->private_state, struct writev_state);
+	size_t to_write, written;
+	int i;
+
+	to_write = 0;
+
+	for (i=0; i<state->count; i++) {
+		to_write += state->iov[i].iov_len;
+	}
+
+	written = sys_writev(state->fd, state->iov, state->count);
+	if (written == -1) {
+		tevent_req_error(req, errno);
+		return;
+	}
+	if (written == 0) {
+		tevent_req_error(req, EPIPE);
+		return;
+	}
+	state->total_size += written;
+
+	if (written == to_write) {
+		tevent_req_done(req);
+		return;
+	}
+
+	/*
+	 * We've written less than we were asked to, drop stuff from
+	 * state->iov.
+	 */
+
+	while (written > 0) {
+		if (written < state->iov[0].iov_len) {
+			state->iov[0].iov_base =
+				(char *)state->iov[0].iov_base + written;
+			state->iov[0].iov_len -= written;
+			break;
+		}
+		written = state->iov[0].iov_len;
+		state->iov += 1;
+		state->count -= 1;
+	}
+}
+
+ssize_t writev_recv(struct tevent_req *req, int *perrno)
+{
+	struct writev_state *state = talloc_get_type_abort(
+		req->private_state, struct writev_state);
+
+	if (tevent_req_is_unix_error(req, perrno)) {
+		return -1;
+	}
+	return state->total_size;
+}
+
+struct read_packet_state {
+	int fd;
+	uint8_t *buf;
+	size_t nread;
+	ssize_t (*more)(uint8_t *buf, size_t buflen, void *private_data);
+	void *private_data;
+};
+
+static void read_packet_handler(struct tevent_context *ev,
+				struct tevent_fd *fde,
+				uint16_t flags, void *private_data);
+
+struct tevent_req *read_packet_send(TALLOC_CTX *mem_ctx,
+				    struct tevent_context *ev,
+				    int fd, size_t initial,
+				    ssize_t (*more)(uint8_t *buf,
+						    size_t buflen,
+						    void *private_data),
+				    void *private_data)
+{
+	struct tevent_req *result;
+	struct read_packet_state *state;
+	struct tevent_fd *fde;
+
+	result = tevent_req_create(mem_ctx, &state, struct read_packet_state);
+	if (result == NULL) {
+		return NULL;
+	}
+	state->fd = fd;
+	state->nread = 0;
+	state->more = more;
+	state->private_data = private_data;
+
+	state->buf = talloc_array(state, uint8_t, initial);
+	if (state->buf == NULL) {
+		goto fail;
+	}
+
+	fde = tevent_add_fd(ev, state, fd, TEVENT_FD_READ, read_packet_handler,
+			    result);
+	if (fde == NULL) {
+		goto fail;
+	}
+	return result;
+ fail:
+	TALLOC_FREE(result);
+	return NULL;
+}
+
+static void read_packet_handler(struct tevent_context *ev,
+				struct tevent_fd *fde,
+				uint16_t flags, void *private_data)
+{
+	struct tevent_req *req = talloc_get_type_abort(
+		private_data, struct tevent_req);
+	struct read_packet_state *state = talloc_get_type_abort(
+		req->private_state, struct read_packet_state);
+	size_t total = talloc_get_size(state->buf);
+	ssize_t nread, more;
+	uint8_t *tmp;
+
+	nread = read(state->fd, state->buf+state->nread, total-state->nread);
+	if (nread == -1) {
+		tevent_req_error(req, errno);
+		return;
+	}
+	if (nread == 0) {
+		tevent_req_error(req, EPIPE);
+		return;
+	}
+
+	state->nread += nread;
+	if (state->nread < total) {
+		/* Come back later */
+		return;
+	}
+
+	/*
+	 * We got what was initially requested. See if "more" asks for -- more.
+	 */
+	if (state->more == NULL) {
+		/* Nobody to ask, this is a async read_data */
+		tevent_req_done(req);
+		return;
+	}
+
+	more = state->more(state->buf, total, state->private_data);
+	if (more == -1) {
+		/* We got an invalid packet, tell the caller */
+		tevent_req_error(req, EIO);
+		return;
+	}
+	if (more == 0) {
+		/* We're done, full packet received */
+		tevent_req_done(req);
+		return;
+	}
+
+	tmp = TALLOC_REALLOC_ARRAY(state, state->buf, uint8_t, total+more);
+	if (tevent_req_nomem(tmp, req)) {
+		return;
+	}
+	state->buf = tmp;
+}
+
+ssize_t read_packet_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+			 uint8_t **pbuf, int *perrno)
+{
+	struct read_packet_state *state = talloc_get_type_abort(
+		req->private_state, struct read_packet_state);
+
+	if (tevent_req_is_unix_error(req, perrno)) {
+		return -1;
+	}
+	*pbuf = talloc_move(mem_ctx, &state->buf);
+	return talloc_get_size(*pbuf);
+}