Functions for buffering input data
diff --git a/contiki/uip/uipbuf.h b/contiki/uip/uipbuf.h
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+/**
+ * \file
+ * uIP data buffering helper functions.
+ * \author
+ * Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#ifndef __UIPBUF_H__
+#define __UIPBUF_H__
+
+#include "uip.h"
+
+/**
+ * \defgroup uipbuf uIP data buffering helper library.
+ *
+ * The event driven API that uIP uses can be tricky to use when
+ * dealing with incoming TCP data. The data can be split over any
+ * number of incoming segments and uIP does not provide any stream
+ * abstraction by itself. To remedy this, the uIP data buffering
+ * helper library provides a set of functions that make buffering data
+ * easier.
+ *
+ * The data buffering library provides a structure that holds a
+ * pointer to a buffer and the state of the buffer, as well as a set
+ * of functions for manipulating the buffer state. The functions are
+ * intended to facilitate buffering of both data that is of a known
+ * size and data that is terminated by a specified byte.
+ *
+ * @{
+ */
+
+/**
+ * Return value of the buffering functions that indicates that a
+ * buffer was not filled by incoming data.
+ *
+ * \hideinitializer
+ */
+#define UIPBUF_NOT_FULL 0
+#define UIPBUF_NOT_FOUND 0
+
+/**
+ * Return value of the buffering functions that indicates that a
+ * buffer was completely filled by incoming data.
+ *
+ * \hideinitializer
+ */
+#define UIPBUF_FULL 1
+
+/**
+ * Return value of the buffering functions that indicates that an
+ * end-marker byte was found.
+ *
+ * \hideinitializer
+ */
+#define UIPBUF_FOUND 2
+
+/**
+ * The structure that holds the state of a uIP buffer.
+ *
+ * This structure holds the state of a uIP buffer. The structure has
+ * no user-visible elements, but is used through the functions
+ * provided by the library.
+ *
+ * \hideinitializer
+ */
+struct uipbuf_buffer {
+ u8_t *ptr, *buffer;
+ unsigned short left, bufsize;
+};
+
+/**
+ * Set up a new uIP buffer structure.
+ *
+ * This function is used for setting up a uIP buffer structure with a
+ * specified size. The function should be called the first time a uIP
+ * buffer is used. The caller must provide the memory for holding the
+ * buffered bytes and the size of the buffer memory.
+ *
+ * \param buf A pointer to a uipbuf_buffer structure that is to be
+ * initialized.
+ *
+ * \param bufptr A pointer to the memory for holding the buffered
+ * data.
+ *
+ * \param size The size of the buffer memory.
+ *
+ */
+void uipbuf_setup(struct uipbuf_buffer *buf,
+ u8_t *bufptr, u16_t size);
+
+/**
+ * Buffer data until the buffer is full.
+ *
+ * This function puts data into the buffer, but no more than the
+ * buffer can hold.
+ *
+ * \param buf A pointer to the ::uipbuf_buffer structure that holds
+ * the state of the buffer.
+ *
+ * \param dataptr A pointer to the data that is to be buffered.
+ *
+ * \param datalen The length of the data that is to be buffered.
+ *
+ * \return If the buffer was not filled, the value UIPBUF_NOT_FULL
+ * is returned. If the buffer was filled, the number of bytes that
+ * could not be buffered is returned. If the buffer was exactly filled
+ * with the data, the value of 0 is returned.
+ *
+ */
+u8_t uipbuf_bufdata(struct uipbuf_buffer *buf, u16_t len,
+ u8_t **dataptr, u16_t *datalen);
+
+/**
+ * Buffer data until a specific character is found or the buffer is full.
+ *
+ * This function puts data into the buffer until a specific marker
+ * byte is found. The marker byte is put into the buffer at the end of
+ * the data.
+ *
+ * \param buf A pointer to the ::uipbuf_buffer structure that holds
+ * the state of the buffer.
+ *
+ * \param dataptr A pointer to the data that is to be buffered.
+ *
+ * \param datalen The length of the data that is to be buffered.
+ *
+ * \param byte The end-marker byte that indicates the end of the data
+ * that is to be buffered.
+ *
+ * \return This function returns the number of protruding bytes after
+ * the end-marker byte, if the marker was found. If the marker was not
+ * found and all of the data was buffered, the value of
+ * UIPBUF_NOT_FOUND is returned. If the marker was not found, but the
+ * data made the buffer fill up, the value of UIPBUF_FULL is returned.
+ *
+ */
+u8_t uipbuf_bufdata_endmarker(struct uipbuf_buffer *buf, u8_t endmarker,
+ u8_t **dataptr, u16_t *datalen);
+
+u16_t uipbuf_len(struct uipbuf_buffer *buf);
+
+/** @} */
+
+#endif /* __UIPBUF_H__ */