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+/****************************************************************************
+**
+** Copyright (C) 2016 Intel Corporation
+**
+** Permission is hereby granted, free of charge, to any person obtaining a copy
+** of this software and associated documentation files (the "Software"), to deal
+** in the Software without restriction, including without limitation the rights
+** to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+** copies of the Software, and to permit persons to whom the Software is
+** furnished to do so, subject to the following conditions:
+**
+** The above copyright notice and this permission notice shall be included in
+** all copies or substantial portions of the Software.
+**
+** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+** FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+** AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+** OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+** THE SOFTWARE.
+**
+****************************************************************************/
+
+#ifndef _BSD_SOURCE
+#define _BSD_SOURCE 1
+#endif
+#ifndef _DEFAULT_SOURCE
+#define _DEFAULT_SOURCE 1
+#endif
+#ifndef __STDC_LIMIT_MACROS
+#  define __STDC_LIMIT_MACROS 1
+#endif
+
+#include "cbor.h"
+#include "cborinternal_p.h"
+#include "compilersupport_p.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+/**
+ * \defgroup CborEncoding Encoding to CBOR
+ * \brief Group of functions used to encode data to CBOR.
+ *
+ * CborEncoder is used to encode data into a CBOR stream. The outermost
+ * CborEncoder is initialized by calling cbor_encoder_init(), with the buffer
+ * where the CBOR stream will be stored. The outermost CborEncoder is usually
+ * used to encode exactly one item, most often an array or map. It is possible
+ * to encode more than one item, but care must then be taken on the decoder
+ * side to ensure the state is reset after each item was decoded.
+ *
+ * Nested CborEncoder objects are created using cbor_encoder_create_array() and
+ * cbor_encoder_create_map(), later closed with cbor_encoder_close_container()
+ * or cbor_encoder_close_container_checked(). The pairs of creation and closing
+ * must be exactly matched and their parameters are always the same.
+ *
+ * CborEncoder writes directly to the user-supplied buffer, without extra
+ * buffering. CborEncoder does not allocate memory and CborEncoder objects are
+ * usually created on the stack of the encoding functions.
+ *
+ * The example below initializes a CborEncoder object with a buffer and encodes
+ * a single integer.
+ *
+ * \code
+ *      uint8_t buf[16];
+ *      CborEncoder encoder;
+ *      cbor_encoder_init(&encoder, &buf, sizeof(buf), 0);
+ *      cbor_encode_int(&encoder, some_value);
+ * \endcode
+ *
+ * As explained before, usually the outermost CborEncoder object is used to add
+ * one array or map, which in turn contains multiple elements. The example
+ * below creates a CBOR map with one element: a key "foo" and a boolean value.
+ *
+ * \code
+ *      uint8_t buf[16];
+ *      CborEncoder encoder, mapEncoder;
+ *      cbor_encoder_init(&encoder, &buf, sizeof(buf), 0);
+ *      cbor_encoder_create_map(&encoder, &mapEncoder, 1);
+ *      cbor_encode_text_stringz(&mapEncoder, "foo");
+ *      cbor_encode_boolean(&mapEncoder, some_value);
+ *      cbor_encoder_close_container(&encoder, &mapEncoder);
+ * \endcode
+ *
+ * <h3 class="groupheader">Error checking and buffer size</h3>
+ *
+ * All functions operating on CborEncoder return a condition of type CborError.
+ * If the encoding was successful, they return CborNoError. Some functions do
+ * extra checking on the input provided and may return some other error
+ * conditions (for example, cbor_encode_simple_value() checks that the type is
+ * of the correct type).
+ *
+ * In addition, all functions check whether the buffer has enough bytes to
+ * encode the item being appended. If that is not possible, they return
+ * CborErrorOutOfMemory.
+ *
+ * It is possible to continue with the encoding of data past the first function
+ * that returns CborErrorOutOfMemory. CborEncoder functions will not overrun
+ * the buffer, but will instead count how many more bytes are needed to
+ * complete the encoding. At the end, you can obtain that count by calling
+ * cbor_encoder_get_extra_bytes_needed().
+ *
+ * \section1 Finalizing the encoding
+ *
+ * Once all items have been appended and the containers have all been properly
+ * closed, the user-supplied buffer will contain the CBOR stream and may be
+ * immediately used. To obtain the size of the buffer, call
+ * cbor_encoder_get_buffer_size() with the original buffer pointer.
+ *
+ * The example below illustrates how one can encode an item with error checking
+ * and then pass on the buffer for network sending.
+ *
+ * \code
+ *      uint8_t buf[16];
+ *      CborError err;
+ *      CborEncoder encoder, mapEncoder;
+ *      cbor_encoder_init(&encoder, &buf, sizeof(buf), 0);
+ *      err = cbor_encoder_create_map(&encoder, &mapEncoder, 1);
+ *      if (!err)
+ *          return err;
+ *      err = cbor_encode_text_stringz(&mapEncoder, "foo");
+ *      if (!err)
+ *          return err;
+ *      err = cbor_encode_boolean(&mapEncoder, some_value);
+ *      if (!err)
+ *          return err;
+ *      err = cbor_encoder_close_container_checked(&encoder, &mapEncoder);
+ *      if (!err)
+ *          return err;
+ *
+ *      size_t len = cbor_encoder_get_buffer_size(&encoder, buf);
+ *      send_payload(buf, len);
+ *      return CborNoError;
+ * \endcode
+ *
+ * Finally, the example below expands on the one above and also
+ * deals with dynamically growing the buffer if the initial allocation wasn't
+ * big enough. Note the two places where the error checking was replaced with
+ * an cbor_assertion, showing where the author assumes no error can occur.
+ *
+ * \code
+ * uint8_t *encode_string_array(const char **strings, int n, size_t *bufsize)
+ * {
+ *     CborError err;
+ *     CborEncoder encoder, arrayEncoder;
+ *     size_t size = 256;
+ *     uint8_t *buf = NULL;
+ *
+ *     while (1) {
+ *         int i;
+ *         size_t more_bytes;
+ *         uint8_t *nbuf = realloc(buf, size);
+ *         if (nbuf == NULL)
+ *             goto error;
+ *         buf = nbuf;
+ *
+ *         cbor_encoder_init(&encoder, &buf, size, 0);
+ *         err = cbor_encoder_create_array(&encoder, &arrayEncoder, n);
+ *         cbor_assert(err);         // can't fail, the buffer is always big enough
+ *
+ *         for (i = 0; i < n; ++i) {
+ *             err = cbor_encode_text_stringz(&arrayEncoder, strings[i]);
+ *             if (err && err != CborErrorOutOfMemory)
+ *                 goto error;
+ *         }
+ *
+ *         err = cbor_encoder_close_container_checked(&encoder, &arrayEncoder);
+ *         cbor_assert(err);         // shouldn't fail!
+ *
+ *         more_bytes = cbor_encoder_get_extra_bytes_needed(encoder);
+ *         if (more_size) {
+ *             // buffer wasn't big enough, try again
+ *             size += more_bytes;
+ *             continue;
+ *         }
+ *
+ *         *bufsize = cbor_encoder_get_buffer_size(encoder, buf);
+ *         return buf;
+ *     }
+ *  error:
+ *     free(buf);
+ *     return NULL;
+ *  }
+ * \endcode
+ */
+
+/**
+ * \addtogroup CborEncoding
+ * @{
+ */
+
+/**
+ * \struct CborEncoder
+ * Structure used to encode to CBOR.
+ */
+
+/**
+ * Initializes a CborEncoder structure \a encoder by pointing it to buffer \a
+ * buffer of size \a size. The \a flags field is currently unused and must be
+ * zero.
+ */
+void cbor_encoder_init(CborEncoder *encoder, uint8_t *buffer, size_t size, int flags)
+{
+    encoder->data.ptr = buffer;
+    encoder->end = buffer + size;
+    encoder->remaining = 2;
+    encoder->flags = flags;
+}
+
+static inline void put16(void *where, uint16_t v)
+{
+    v = cbor_htons(v);
+    memcpy(where, &v, sizeof(v));
+}
+
+/* Note: Since this is currently only used in situations where OOM is the only
+ * valid error, we KNOW this to be true.  Thus, this function now returns just 'true',
+ * but if in the future, any function starts returning a non-OOM error, this will need
+ * to be changed to the test.  At the moment, this is done to prevent more branches
+ * being created in the tinycbor output */
+static inline bool isOomError(CborError err)
+{
+    (void) err;
+    return true;
+}
+
+static inline void put32(void *where, uint32_t v)
+{
+    v = cbor_htonl(v);
+    memcpy(where, &v, sizeof(v));
+}
+
+static inline void put64(void *where, uint64_t v)
+{
+    v = cbor_htonll(v);
+    memcpy(where, &v, sizeof(v));
+}
+
+static inline bool would_overflow(CborEncoder *encoder, size_t len)
+{
+    ptrdiff_t remaining = (ptrdiff_t)encoder->end;
+    remaining -= remaining ? (ptrdiff_t)encoder->data.ptr : encoder->data.bytes_needed;
+    remaining -= (ptrdiff_t)len;
+    return unlikely(remaining < 0);
+}
+
+static inline void advance_ptr(CborEncoder *encoder, size_t n)
+{
+    if (encoder->end)
+        encoder->data.ptr += n;
+    else
+        encoder->data.bytes_needed += n;
+}
+
+static inline CborError append_to_buffer(CborEncoder *encoder, const void *data, size_t len)
+{
+    if (would_overflow(encoder, len)) {
+        if (encoder->end != NULL) {
+            len -= encoder->end - encoder->data.ptr;
+            encoder->end = NULL;
+            encoder->data.bytes_needed = 0;
+        }
+
+        advance_ptr(encoder, len);
+        return CborErrorOutOfMemory;
+    }
+
+    memcpy(encoder->data.ptr, data, len);
+    encoder->data.ptr += len;
+    return CborNoError;
+}
+
+static inline CborError append_byte_to_buffer(CborEncoder *encoder, uint8_t byte)
+{
+    return append_to_buffer(encoder, &byte, 1);
+}
+
+static inline CborError encode_number_no_update(CborEncoder *encoder, uint64_t ui, uint8_t shiftedMajorType)
+{
+    /* Little-endian would have been so much more convenient here:
+     * We could just write at the beginning of buf but append_to_buffer
+     * only the necessary bytes.
+     * Since it has to be big endian, do it the other way around:
+     * write from the end. */
+    uint64_t buf[2];
+    uint8_t *const bufend = (uint8_t *)buf + sizeof(buf);
+    uint8_t *bufstart = bufend - 1;
+    put64(buf + 1, ui);     /* we probably have a bunch of zeros in the beginning */
+
+    if (ui < Value8Bit) {
+        *bufstart += shiftedMajorType;
+    } else {
+        uint8_t more = 0;
+        if (ui > 0xffU)
+            ++more;
+        if (ui > 0xffffU)
+            ++more;
+        if (ui > 0xffffffffU)
+            ++more;
+        bufstart -= (size_t)1 << more;
+        *bufstart = shiftedMajorType + Value8Bit + more;
+    }
+
+    return append_to_buffer(encoder, bufstart, bufend - bufstart);
+}
+
+static inline void saturated_decrement(CborEncoder *encoder)
+{
+    if (encoder->remaining)
+        --encoder->remaining;
+}
+
+static inline CborError encode_number(CborEncoder *encoder, uint64_t ui, uint8_t shiftedMajorType)
+{
+    saturated_decrement(encoder);
+    return encode_number_no_update(encoder, ui, shiftedMajorType);
+}
+
+/**
+ * Appends the unsigned 64-bit integer \a value to the CBOR stream provided by
+ * \a encoder.
+ *
+ * \sa cbor_encode_negative_int, cbor_encode_int
+ */
+CborError cbor_encode_uint(CborEncoder *encoder, uint64_t value)
+{
+    return encode_number(encoder, value, UnsignedIntegerType << MajorTypeShift);
+}
+
+/**
+ * Appends the negative 64-bit integer whose absolute value is \a
+ * absolute_value to the CBOR stream provided by \a encoder.
+ *
+ * If the value \a absolute_value is zero, this function encodes -2^64.
+ *
+ * \sa cbor_encode_uint, cbor_encode_int
+ */
+CborError cbor_encode_negative_int(CborEncoder *encoder, uint64_t absolute_value)
+{
+    return encode_number(encoder, absolute_value - 1, NegativeIntegerType << MajorTypeShift);
+}
+
+/**
+ * Appends the signed 64-bit integer \a value to the CBOR stream provided by
+ * \a encoder.
+ *
+ * \sa cbor_encode_negative_int, cbor_encode_uint
+ */
+CborError cbor_encode_int(CborEncoder *encoder, int64_t value)
+{
+    /* adapted from code in RFC 7049 appendix C (pseudocode) */
+    uint64_t ui = value >> 63;              /* extend sign to whole length */
+    uint8_t majorType = ui & 0x20;          /* extract major type */
+    ui ^= value;                            /* complement negatives */
+    return encode_number(encoder, ui, majorType);
+}
+
+/**
+ * Appends the CBOR Simple Type of value \a value to the CBOR stream provided by
+ * \a encoder.
+ *
+ * This function may return error CborErrorIllegalSimpleType if the \a value
+ * variable contains a number that is not a valid simple type.
+ */
+CborError cbor_encode_simple_value(CborEncoder *encoder, uint8_t value)
+{
+#ifndef CBOR_ENCODER_NO_CHECK_USER
+    /* check if this is a valid simple type */
+    if (value >= HalfPrecisionFloat && value <= Break)
+        return CborErrorIllegalSimpleType;
+#endif
+    return encode_number(encoder, value, SimpleTypesType << MajorTypeShift);
+}
+
+/**
+ * Appends the floating-point value of type \a fpType and pointed to by \a
+ * value to the CBOR stream provided by \a encoder. The value of \a fpType must
+ * be one of CborHalfFloatType, CborFloatType or CborDoubleType, otherwise the
+ * behavior of this function is undefined.
+ *
+ * This function is useful for code that needs to pass through floating point
+ * values but does not wish to have the actual floating-point code.
+ *
+ * \sa cbor_encode_half_float, cbor_encode_float, cbor_encode_double
+ */
+CborError cbor_encode_floating_point(CborEncoder *encoder, CborType fpType, const void *value)
+{
+    unsigned size;
+    uint8_t buf[1 + sizeof(uint64_t)];
+    cbor_assert(fpType == CborHalfFloatType || fpType == CborFloatType || fpType == CborDoubleType);
+    buf[0] = fpType;
+
+    size = 2U << (fpType - CborHalfFloatType);
+    if (size == 8)
+        put64(buf + 1, *(const uint64_t*)value);
+    else if (size == 4)
+        put32(buf + 1, *(const uint32_t*)value);
+    else
+        put16(buf + 1, *(const uint16_t*)value);
+    saturated_decrement(encoder);
+    return append_to_buffer(encoder, buf, size + 1);
+}
+
+/**
+ * Appends the CBOR tag \a tag to the CBOR stream provided by \a encoder.
+ *
+ * \sa CborTag
+ */
+CborError cbor_encode_tag(CborEncoder *encoder, CborTag tag)
+{
+    /* tags don't count towards the number of elements in an array or map */
+    return encode_number_no_update(encoder, tag, TagType << MajorTypeShift);
+}
+
+static CborError encode_string(CborEncoder *encoder, size_t length, uint8_t shiftedMajorType, const void *string)
+{
+    CborError err = encode_number(encoder, length, shiftedMajorType);
+    if (err && !isOomError(err))
+        return err;
+    return append_to_buffer(encoder, string, length);
+}
+
+/**
+ * \fn CborError cbor_encode_text_stringz(CborEncoder *encoder, const char *string)
+ *
+ * Appends the null-terminated text string \a string to the CBOR stream
+ * provided by \a encoder. CBOR requires that \a string be valid UTF-8, but
+ * TinyCBOR makes no verification of correctness. The terminating null is not
+ * included in the stream.
+ *
+ * \sa cbor_encode_text_string, cbor_encode_byte_string
+ */
+
+/**
+ * Appends the text string \a string of length \a length to the CBOR stream
+ * provided by \a encoder. CBOR requires that \a string be valid UTF-8, but
+ * TinyCBOR makes no verification of correctness.
+ *
+ * \sa CborError cbor_encode_text_stringz, cbor_encode_byte_string
+ */
+CborError cbor_encode_byte_string(CborEncoder *encoder, const uint8_t *string, size_t length)
+{
+    return encode_string(encoder, length, ByteStringType << MajorTypeShift, string);
+}
+
+/**
+ * Appends the byte string \a string of length \a length to the CBOR stream
+ * provided by \a encoder. CBOR byte strings are arbitrary raw data.
+ *
+ * \sa cbor_encode_text_stringz, cbor_encode_text_string
+ */
+CborError cbor_encode_text_string(CborEncoder *encoder, const char *string, size_t length)
+{
+    return encode_string(encoder, length, TextStringType << MajorTypeShift, string);
+}
+
+#ifdef __GNUC__
+__attribute__((noinline))
+#endif
+static CborError create_container(CborEncoder *encoder, CborEncoder *container, size_t length, uint8_t shiftedMajorType)
+{
+    CborError err;
+    container->data.ptr = encoder->data.ptr;
+    container->end = encoder->end;
+    saturated_decrement(encoder);
+    container->remaining = length + 1;      /* overflow ok on CborIndefiniteLength */
+
+    cbor_static_assert(((MapType << MajorTypeShift) & CborIteratorFlag_ContainerIsMap) == CborIteratorFlag_ContainerIsMap);
+    cbor_static_assert(((ArrayType << MajorTypeShift) & CborIteratorFlag_ContainerIsMap) == 0);
+    container->flags = shiftedMajorType & CborIteratorFlag_ContainerIsMap;
+
+    if (length == CborIndefiniteLength) {
+        container->flags |= CborIteratorFlag_UnknownLength;
+        err = append_byte_to_buffer(container, shiftedMajorType + IndefiniteLength);
+    } else {
+        if (shiftedMajorType & CborIteratorFlag_ContainerIsMap)
+            container->remaining += length;
+        err = encode_number_no_update(container, length, shiftedMajorType);
+    }
+    return err;
+}
+
+/**
+ * Creates a CBOR array in the CBOR stream provided by \a encoder and
+ * initializes \a arrayEncoder so that items can be added to the array using
+ * the CborEncoder functions. The array must be terminated by calling either
+ * cbor_encoder_close_container() or cbor_encoder_close_container_checked()
+ * with the same \a encoder and \a arrayEncoder parameters.
+ *
+ * The number of items inserted into the array must be exactly \a length items,
+ * otherwise the stream is invalid. If the number of items is not known when
+ * creating the array, the constant \ref CborIndefiniteLength may be passed as
+ * length instead.
+ *
+ * \sa cbor_encoder_create_map
+ */
+CborError cbor_encoder_create_array(CborEncoder *encoder, CborEncoder *arrayEncoder, size_t length)
+{
+    return create_container(encoder, arrayEncoder, length, ArrayType << MajorTypeShift);
+}
+
+/**
+ * Creates a CBOR map in the CBOR stream provided by \a encoder and
+ * initializes \a mapEncoder so that items can be added to the map using
+ * the CborEncoder functions. The map must be terminated by calling either
+ * cbor_encoder_close_container() or cbor_encoder_close_container_checked()
+ * with the same \a encoder and \a mapEncoder parameters.
+ *
+ * The number of pair of items inserted into the map must be exactly \a length
+ * items, otherwise the stream is invalid. If the number is not known
+ * when creating the map, the constant \ref CborIndefiniteLength may be passed as
+ * length instead.
+ *
+ * \b{Implementation limitation:} TinyCBOR cannot encode more than SIZE_MAX/2
+ * key-value pairs in the stream. If the length \a length is larger than this
+ * value (and is not \ref CborIndefiniteLength), this function returns error
+ * CborErrorDataTooLarge.
+ *
+ * \sa cbor_encoder_create_array
+ */
+CborError cbor_encoder_create_map(CborEncoder *encoder, CborEncoder *mapEncoder, size_t length)
+{
+    if (length != CborIndefiniteLength && length > SIZE_MAX / 2)
+        return CborErrorDataTooLarge;
+    return create_container(encoder, mapEncoder, length, MapType << MajorTypeShift);
+}
+
+/**
+ * Closes the CBOR container (array or map) provided by \a containerEncoder and
+ * updates the CBOR stream provided by \a encoder. Both parameters must be the
+ * same as were passed to cbor_encoder_create_array() or
+ * cbor_encoder_create_map().
+ *
+ * Since version 0.5, this function verifies that the number of items (or pairs
+ * of items, in the case of a map) was correct. It is no longer necessary to call
+ * cbor_encoder_close_container_checked() instead.
+ *
+ * \sa cbor_encoder_create_array(), cbor_encoder_create_map()
+ */
+CborError cbor_encoder_close_container(CborEncoder *encoder, const CborEncoder *containerEncoder)
+{
+    if (encoder->end)
+        encoder->data.ptr = containerEncoder->data.ptr;
+    else
+        encoder->data.bytes_needed = containerEncoder->data.bytes_needed;
+    encoder->end = containerEncoder->end;
+    if (containerEncoder->flags & CborIteratorFlag_UnknownLength)
+        return append_byte_to_buffer(encoder, BreakByte);
+
+    if (containerEncoder->remaining != 1)
+        return containerEncoder->remaining == 0 ? CborErrorTooManyItems : CborErrorTooFewItems;
+
+    if (!encoder->end)
+        return CborErrorOutOfMemory;    /* keep the state */
+    return CborNoError;
+}
+
+/**
+ * \fn CborError cbor_encode_boolean(CborEncoder *encoder, bool value)
+ *
+ * Appends the boolean value \a value to the CBOR stream provided by \a encoder.
+ */
+
+/**
+ * \fn CborError cbor_encode_null(CborEncoder *encoder)
+ *
+ * Appends the CBOR type representing a null value to the CBOR stream provided
+ * by \a encoder.
+ *
+ * \sa cbor_encode_undefined()
+ */
+
+/**
+ * \fn CborError cbor_encode_undefined(CborEncoder *encoder)
+ *
+ * Appends the CBOR type representing an undefined value to the CBOR stream
+ * provided by \a encoder.
+ *
+ * \sa cbor_encode_null()
+ */
+
+/**
+ * \fn CborError cbor_encode_half_float(CborEncoder *encoder, const void *value)
+ *
+ * Appends the IEEE 754 half-precision (16-bit) floating point value pointed to
+ * by \a value to the CBOR stream provided by \a encoder.
+ *
+ * \sa cbor_encode_floating_point(), cbor_encode_float(), cbor_encode_double()
+ */
+
+/**
+ * \fn CborError cbor_encode_float(CborEncoder *encoder, float value)
+ *
+ * Appends the IEEE 754 single-precision (32-bit) floating point value \a value
+ * to the CBOR stream provided by \a encoder.
+ *
+ * \sa cbor_encode_floating_point(), cbor_encode_half_float(), cbor_encode_double()
+ */
+
+/**
+ * \fn CborError cbor_encode_double(CborEncoder *encoder, double value)
+ *
+ * Appends the IEEE 754 double-precision (64-bit) floating point value \a value
+ * to the CBOR stream provided by \a encoder.
+ *
+ * \sa cbor_encode_floating_point(), cbor_encode_half_float(), cbor_encode_float()
+ */
+
+/**
+ * \fn size_t cbor_encoder_get_buffer_size(const CborEncoder *encoder, const uint8_t *buffer)
+ *
+ * Returns the total size of the buffer starting at \a buffer after the
+ * encoding finished without errors. The \a encoder and \a buffer arguments
+ * must be the same as supplied to cbor_encoder_init().
+ *
+ * If the encoding process had errors, the return value of this function is
+ * meaningless. If the only errors were CborErrorOutOfMemory, instead use
+ * cbor_encoder_get_extra_bytes_needed() to find out by how much to grow the
+ * buffer before encoding again.
+ *
+ * See \ref CborEncoding for an example of using this function.
+ *
+ * \sa cbor_encoder_init(), cbor_encoder_get_extra_bytes_needed(), CborEncoding
+ */
+
+/**
+ * \fn size_t cbor_encoder_get_extra_bytes_needed(const CborEncoder *encoder)
+ *
+ * Returns how many more bytes the original buffer supplied to
+ * cbor_encoder_init() needs to be extended by so that no CborErrorOutOfMemory
+ * condition will happen for the encoding. If the buffer was big enough, this
+ * function returns 0. The \a encoder must be the original argument as passed
+ * to cbor_encoder_init().
+ *
+ * This function is usually called after an encoding sequence ended with one or
+ * more CborErrorOutOfMemory errors, but no other error. If any other error
+ * happened, the return value of this function is meaningless.
+ *
+ * See \ref CborEncoding for an example of using this function.
+ *
+ * \sa cbor_encoder_init(), cbor_encoder_get_buffer_size(), CborEncoding
+ */
+
+/** @} */