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diff --git a/ctdb/common/pkt_read.h b/ctdb/common/pkt_read.h
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+/*
+ API for reading packets using fixed and dynamic buffer
+
+ Copyright (C) Amitay Isaacs 2015
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __CTDB_PKT_READ_H__
+#define __CTDB_PKT_READ_H__
+
+#include <talloc.h>
+#include <tevent.h>
+
+/**
+ * @file pkt_read.h
+ *
+ * @brief Read a packet using fixed size buffer or allocated memory.
+ *
+ * CTDB communication uses lots of small packets. This abstraction avoids the
+ * need to allocate memory for small packets. Only if the received packet is
+ * larger than the fixed memory buffer, use talloc to allocate memory.
+ */
+
+/**
+ * @brief Start async computation to read a packet
+ *
+ * This returns a tevent request to read a packet from given fd. The fd
+ * should be nonblocking. Freeing this request will free all the memory
+ * associated with the request.
+ *
+ * @param[in] mem_ctx Talloc memory context
+ * @param[in] ev Tevent context
+ * @param[in] fd The non-blocking file/socket descriptor to read from
+ * @param[in] initial Initial amount of data to read
+ * @param[in] buf The static buffer to read data in
+ * @param[in] buflen The size of the static buffer
+ * @param[in] more The function to check if the bytes read forms a packet
+ * @param[in] private_data Private data to pass to more function
+ * @return new tevent request or NULL on failure
+ */
+struct tevent_req *pkt_read_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ int fd, size_t initial,
+ uint8_t *buf, size_t buflen,
+ ssize_t (*more)(uint8_t *buf,
+ size_t buflen,
+ void *private_data),
+ void *private_data);
+
+/**
+ * @brief Function to actually read data from the socket
+ *
+ * This function should be called, when tevent fd event is triggered. This
+ * function has the syntax of tevent_fd_handler_t. The private_data for this
+ * function is the tevent request created by pkt_read_send function.
+ *
+ * @param[in] ev Tevent context
+ * @param[in] fde Tevent fd context
+ * @param[in] flags Tevent fd flags
+ * @param[in] req The active tevent request
+ */
+void pkt_read_handler(struct tevent_context *ev, struct tevent_fd *fde,
+ uint16_t flags, struct tevent_req *req);
+
+/**
+ * @brief Retrieve a packet
+ *
+ * This function returns the pkt read from fd.
+ *
+ * @param[in] req Tevent request
+ * @param[in] mem_ctx Talloc memory context
+ * @param[out] pbuf The pointer to the buffer
+ * @param[out] free_buf Boolean to indicate that caller should free buffer
+ * @param[out] perrno errno in case of failure
+ * @return the size of the pkt, or -1 on failure
+ *
+ * If the pkt data is dynamically allocated, then it is moved under the
+ * specified talloc memory context and free_buf is set to true. It is the
+ * responsibility of the caller to the free the memory returned.
+ *
+ * If the pkt data is stored in the fixed buffer, then free_buf is set to false.
+ */
+ssize_t pkt_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+ uint8_t **pbuf, bool *free_buf, int *perrno);
+
+#endif /* __CTDB_PKT_READ_H__ */