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/* pb_encode.c -- encode a protobuf using minimal resources

 *

 * 2011 Petteri Aimonen <jpa@kapsi.fi>

 */

#include "pb.h"

#include "pb_encode.h"

#include "pb_common.h"

/* Use the GCC warn_unused_result attribute to check that all return values

 * are propagated correctly. On other compilers and gcc before 3.4.0 just

 * ignore the annotation.

 */

#if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)

    #define checkreturn

#else

    #define checkreturn __attribute__((warn_unused_result))

#endif

/**************************************

 * Declarations internal to this file *

 **************************************/

typedef bool (*pb_encoder_t)(pb_ostream_t *stream, const pb_field_t *field, const void *src) checkreturn;

static bool checkreturn buf_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count);

static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *field, const void *pData, size_t count, pb_encoder_t func);

static bool checkreturn encode_field(pb_ostream_t *stream, const pb_field_t *field, const void *pData);

static bool checkreturn default_extension_encoder(pb_ostream_t *stream, const pb_extension_t *extension);

static bool checkreturn encode_extension_field(pb_ostream_t *stream, const pb_field_t *field, const void *pData);

static void *pb_const_cast(const void *p);

static bool checkreturn pb_enc_bool(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_varint(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_uvarint(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_fixed32(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_fixed64(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src);

static bool checkreturn pb_enc_fixed_length_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src);

#ifdef PB_WITHOUT_64BIT

#define pb_int64_t int32_t

#define pb_uint64_t uint32_t

static bool checkreturn pb_encode_negative_varint(pb_ostream_t *stream, pb_uint64_t value);

#else

#define pb_int64_t int64_t

#define pb_uint64_t uint64_t

#endif

/* --- Function pointers to field encoders ---

 * Order in the array must match pb_action_t LTYPE numbering.

 */

static const pb_encoder_t PB_ENCODERS[PB_LTYPES_COUNT] = {

    &pb_enc_bool,

    &pb_enc_varint,

    &pb_enc_uvarint,

    &pb_enc_svarint,

    &pb_enc_fixed32,

    &pb_enc_fixed64,

    &pb_enc_bytes,

    &pb_enc_string,

    &pb_enc_submessage,

    NULL, /* extensions */

    &pb_enc_fixed_length_bytes

};

/*******************************

 * pb_ostream_t implementation *

 *******************************/

static bool checkreturn buf_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count)

{

    size_t i;

    pb_byte_t *dest = (pb_byte_t*)stream->state;

    stream->state = dest + count;

    for (i = 0; i < count; i++)

        dest[i] = buf[i];

    return true;

}

pb_ostream_t pb_ostream_from_buffer(pb_byte_t *buf, size_t bufsize)

{

    pb_ostream_t stream;

#ifdef PB_BUFFER_ONLY

    stream.callback = (void*)1; /* Just a marker value */

#else

    stream.callback = &buf_write;

#endif

    stream.state = buf;

    stream.max_size = bufsize;

    stream.bytes_written = 0;

#ifndef PB_NO_ERRMSG

    stream.errmsg = NULL;

#endif

    return stream;

}

bool checkreturn pb_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count)

{

    if (count > 0 && stream->callback != NULL)

    {

        if (stream->bytes_written + count < stream->bytes_written ||

            stream->bytes_written + count > stream->max_size)

        {

            PB_RETURN_ERROR(stream, "stream full");

        }

#ifdef PB_BUFFER_ONLY

        if (!buf_write(stream, buf, count))

            PB_RETURN_ERROR(stream, "io error");

#else

        if (!stream->callback(stream, buf, count))

            PB_RETURN_ERROR(stream, "io error");

#endif

    }

    stream->bytes_written += count;

    return true;

}

/*************************

 * Encode a single field *

 *************************/

/* Read a bool value without causing undefined behavior even if the value

 * is invalid. See issue #434 and

 * https://stackoverflow.com/questions/27661768/weird-results-for-conditional

 */

static bool safe_read_bool(const void *pSize)

{

    const char *p = (const char *)pSize;

    size_t i;

    for (i = 0; i < sizeof(bool); i++)

    {

        if (p[i] != 0)

            return true;

    }

    return false;

}

/* Encode a static array. Handles the size calculations and possible packing. */

static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *field,

                         const void *pData, size_t count, pb_encoder_t func)

{

    size_t i;

    const void *p;

#ifndef PB_ENCODE_ARRAYS_UNPACKED

    size_t size;

#endif

    if (count == 0)

        return true;

    if (PB_ATYPE(field->type) != PB_ATYPE_POINTER && count > field->array_size)

        PB_RETURN_ERROR(stream, "array max size exceeded");

#ifndef PB_ENCODE_ARRAYS_UNPACKED

    /* We always pack arrays if the datatype allows it. */

    if (PB_LTYPE(field->type) <= PB_LTYPE_LAST_PACKABLE)

    {

        if (!pb_encode_tag(stream, PB_WT_STRING, field->tag))

            return false;

        /* Determine the total size of packed array. */

        if (PB_LTYPE(field->type) == PB_LTYPE_FIXED32)

        {

            size = 4 * count;

        }

        else if (PB_LTYPE(field->type) == PB_LTYPE_FIXED64)

        {

            size = 8 * count;

        }

        else

        {

            pb_ostream_t sizestream = PB_OSTREAM_SIZING;

            p = pData;

            for (i = 0; i < count; i++)

            {

                if (!func(&sizestream, field, p))

                    return false;

                p = (const char*)p + field->data_size;

            }

            size = sizestream.bytes_written;

        }

        if (!pb_encode_varint(stream, (pb_uint64_t)size))

            return false;

        if (stream->callback == NULL)

            return pb_write(stream, NULL, size); /* Just sizing.. */

        /* Write the data */

        p = pData;

        for (i = 0; i < count; i++)

        {

            if (!func(stream, field, p))

                return false;

            p = (const char*)p + field->data_size;

        }

    }

    else

#endif

    {

        p = pData;

        for (i = 0; i < count; i++)

        {

            if (!pb_encode_tag_for_field(stream, field))

                return false;

            /* Normally the data is stored directly in the array entries, but

             * for pointer-type string and bytes fields, the array entries are

             * actually pointers themselves also. So we have to dereference once

             * more to get to the actual data. */

            if (PB_ATYPE(field->type) == PB_ATYPE_POINTER &&

                (PB_LTYPE(field->type) == PB_LTYPE_STRING ||

                 PB_LTYPE(field->type) == PB_LTYPE_BYTES))

            {

                if (!func(stream, field, *(const void* const*)p))

                    return false;

            }

            else

            {

                if (!func(stream, field, p))

                    return false;

            }

            p = (const char*)p + field->data_size;

        }

    }

    return true;

}

/* In proto3, all fields are optional and are only encoded if their value is "non-zero".

 * This function implements the check for the zero value. */

static bool pb_check_proto3_default_value(const pb_field_t *field, const void *pData)

{

    pb_type_t type = field->type;

    const void *pSize = (const char*)pData + field->size_offset;

    if (PB_HTYPE(type) == PB_HTYPE_REQUIRED)

    {

        /* Required proto2 fields inside proto3 submessage, pretty rare case */

        return false;

    }

    else if (PB_HTYPE(type) == PB_HTYPE_REPEATED)

    {

        /* Repeated fields inside proto3 submessage: present if count != 0 */

        if (field->size_offset != 0)

            return *(const pb_size_t*)pSize == 0;

        else if (PB_ATYPE(type) == PB_ATYPE_STATIC)

            return false; /* Fixed length array */

    }

    else if (PB_HTYPE(type) == PB_HTYPE_ONEOF)

    {

        /* Oneof fields */

        return *(const pb_size_t*)pSize == 0;

    }

    else if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL && field->size_offset != 0)

    {

        /* Proto2 optional fields inside proto3 submessage */

        return safe_read_bool(pSize) == false;

    }

    /* Rest is proto3 singular fields */

    if (PB_ATYPE(type) == PB_ATYPE_STATIC)

    {

        if (PB_LTYPE(type) == PB_LTYPE_BYTES)

        {

            const pb_bytes_array_t *bytes = (const pb_bytes_array_t*)pData;

            return bytes->size == 0;

        }

        else if (PB_LTYPE(type) == PB_LTYPE_STRING)

        {

            return *(const char*)pData == '\0';

        }

        else if (PB_LTYPE(type) == PB_LTYPE_FIXED_LENGTH_BYTES)

        {

            /* Fixed length bytes is only empty if its length is fixed

             * as 0. Which would be pretty strange, but we can check

             * it anyway. */

            return field->data_size == 0;

        }

        else if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)

        {

            /* Check all fields in the submessage to find if any of them

             * are non-zero. The comparison cannot be done byte-per-byte

             * because the C struct may contain padding bytes that must

             * be skipped.

             */

            pb_field_iter_t iter;

            if (pb_field_iter_begin(&iter, (const pb_field_t*)field->ptr, pb_const_cast(pData)))

            {

                do

                {

                    if (!pb_check_proto3_default_value(iter.pos, iter.pData))

                    {

                        return false;

                    }

                } while (pb_field_iter_next(&iter));

            }

            return true;

        }

    }

    /* Compares pointers to NULL in case of FT_POINTER */

    if (PB_ATYPE(type) == PB_ATYPE_POINTER && PB_LTYPE(type) > PB_LTYPE_LAST_PACKABLE)

    {

        return !*(const void**)((uintptr_t)pData);

    }

	{

	    /* Catch-all branch that does byte-per-byte comparison for zero value.

	     *

	     * This is for all pointer fields, and for static PB_LTYPE_VARINT,

	     * UVARINT, SVARINT, FIXED32, FIXED64, EXTENSION fields, and also

	     * callback fields. These all have integer or pointer value which

	     * can be compared with 0.

	     */

	    pb_size_t i;

	    const char *p = (const char*)pData;

	    for (i = 0; i < field->data_size; i++)

	    {

	        if (p[i] != 0)

	        {

	            return false;

	        }

	    }

	    return true;

	}

}

/* Encode a field with static or pointer allocation, i.e. one whose data

 * is available to the encoder directly. */

static bool checkreturn encode_basic_field(pb_ostream_t *stream,

    const pb_field_t *field, const void *pData)

{

    pb_encoder_t func;

    bool implicit_has;

    const void *pSize = &implicit_has;

    func = PB_ENCODERS[PB_LTYPE(field->type)];

    if (field->size_offset)

    {

        /* Static optional, repeated or oneof field */

        pSize = (const char*)pData + field->size_offset;

    }

    else if (PB_HTYPE(field->type) == PB_HTYPE_OPTIONAL)

    {

        /* Proto3 style field, optional but without explicit has_ field. */

        implicit_has = !pb_check_proto3_default_value(field, pData);

    }

    else

    {

        /* Required field, always present */

        implicit_has = true;

    }

    if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)

    {

        /* pData is a pointer to the field, which contains pointer to

         * the data. If the 2nd pointer is NULL, it is interpreted as if

         * the has_field was false.

         */

        pData = *(const void* const*)pData;

        implicit_has = (pData != NULL);

    }

    switch (PB_HTYPE(field->type))

    {

        case PB_HTYPE_REQUIRED:

            if (!pData)

                PB_RETURN_ERROR(stream, "missing required field");

            if (!pb_encode_tag_for_field(stream, field))

                return false;

            if (!func(stream, field, pData))

                return false;

            break;

        case PB_HTYPE_OPTIONAL:

            if (safe_read_bool(pSize))

            {

                if (!pb_encode_tag_for_field(stream, field))

                    return false;

                if (!func(stream, field, pData))

                    return false;

            }

            break;

        case PB_HTYPE_REPEATED: {

            pb_size_t count;

            if (field->size_offset != 0) {

                count = *(const pb_size_t*)pSize;

            } else {

                count = field->array_size;

            }

            if (!encode_array(stream, field, pData, count, func))

                return false;

            break;

        }

        case PB_HTYPE_ONEOF:

            if (*(const pb_size_t*)pSize == field->tag)

            {

                if (!pb_encode_tag_for_field(stream, field))

                    return false;

                if (!func(stream, field, pData))

                    return false;

            }

            break;

        default:

            PB_RETURN_ERROR(stream, "invalid field type");

    }

    return true;

}

/* Encode a field with callback semantics. This means that a user function is

 * called to provide and encode the actual data. */

static bool checkreturn encode_callback_field(pb_ostream_t *stream,

    const pb_field_t *field, const void *pData)

{

    const pb_callback_t *callback = (const pb_callback_t*)pData;

#ifdef PB_OLD_CALLBACK_STYLE

    const void *arg = callback->arg;

#else

    void * const *arg = &(callback->arg);

#endif

    if (callback->funcs.encode != NULL)

    {

        if (!callback->funcs.encode(stream, field, arg))

            PB_RETURN_ERROR(stream, "callback error");

    }

    return true;

}

/* Encode a single field of any callback or static type. */

static bool checkreturn encode_field(pb_ostream_t *stream,

    const pb_field_t *field, const void *pData)

{

    switch (PB_ATYPE(field->type))

    {

        case PB_ATYPE_STATIC:

        case PB_ATYPE_POINTER:

            return encode_basic_field(stream, field, pData);

        case PB_ATYPE_CALLBACK:

            return encode_callback_field(stream, field, pData);

        default:

            PB_RETURN_ERROR(stream, "invalid field type");

    }

}

/* Default handler for extension fields. Expects to have a pb_field_t

 * pointer in the extension->type->arg field. */

static bool checkreturn default_extension_encoder(pb_ostream_t *stream,

    const pb_extension_t *extension)

{

    const pb_field_t *field = (const pb_field_t*)extension->type->arg;

    if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)

    {

        /* For pointer extensions, the pointer is stored directly

         * in the extension structure. This avoids having an extra

         * indirection. */

        return encode_field(stream, field, &extension->dest);

    }

    else

    {

        return encode_field(stream, field, extension->dest);

    }

}

/* Walk through all the registered extensions and give them a chance

 * to encode themselves. */

static bool checkreturn encode_extension_field(pb_ostream_t *stream,

    const pb_field_t *field, const void *pData)

{

    const pb_extension_t *extension = *(const pb_extension_t* const *)pData;

    PB_UNUSED(field);

    while (extension)

    {

        bool status;

        if (extension->type->encode)

            status = extension->type->encode(stream, extension);

        else

            status = default_extension_encoder(stream, extension);

        if (!status)

            return false;

        extension = extension->next;

    }

    return true;

}

/*********************

 * Encode all fields *

 *********************/

static void *pb_const_cast(const void *p)

{

    /* Note: this casts away const, in order to use the common field iterator

     * logic for both encoding and decoding. */

    union {

        void *p1;

        const void *p2;

    } t;

    t.p2 = p;

    return t.p1;

}

bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)

{

    pb_field_iter_t iter;

    if (!pb_field_iter_begin(&iter, fields, pb_const_cast(src_struct)))

        return true; /* Empty message type */

    do {

        if (PB_LTYPE(iter.pos->type) == PB_LTYPE_EXTENSION)

        {

            /* Special case for the extension field placeholder */

            if (!encode_extension_field(stream, iter.pos, iter.pData))

                return false;

        }

        else

        {

            /* Regular field */

            if (!encode_field(stream, iter.pos, iter.pData))

                return false;

        }

    } while (pb_field_iter_next(&iter));

    return true;

}

bool pb_encode_delimited(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)

{

    return pb_encode_submessage(stream, fields, src_struct);

}

bool pb_encode_nullterminated(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)

{

    const pb_byte_t zero = 0;

    if (!pb_encode(stream, fields, src_struct))

        return false;

    return pb_write(stream, &zero, 1);

}

bool pb_get_encoded_size(size_t *size, const pb_field_t fields[], const void *src_struct)

{

    pb_ostream_t stream = PB_OSTREAM_SIZING;

    if (!pb_encode(&stream, fields, src_struct))

        return false;

    *size = stream.bytes_written;

    return true;

}

/********************

 * Helper functions *

 ********************/

#ifdef PB_WITHOUT_64BIT

bool checkreturn pb_encode_negative_varint(pb_ostream_t *stream, pb_uint64_t value)

{

  pb_byte_t buffer[10];

  size_t i = 0;

  size_t compensation = 32;/* we need to compensate 32 bits all set to 1 */

  while (value)

  {

    buffer[i] = (pb_byte_t)((value & 0x7F) | 0x80);

    value >>= 7;

    if (compensation)

    {

      /* re-set all the compensation bits we can or need */

      size_t bits = compensation > 7 ? 7 : compensation;

      value ^= (pb_uint64_t)((0xFFu >> (8 - bits)) << 25); /* set the number of bits needed on the lowest of the most significant 7 bits */

      compensation -= bits;

    }

    i++;

  }

  buffer[i - 1] &= 0x7F; /* Unset top bit on last byte */

  return pb_write(stream, buffer, i);

}

#endif

bool checkreturn pb_encode_varint(pb_ostream_t *stream, pb_uint64_t value)

{

    pb_byte_t buffer[10];

    size_t i = 0;

    if (value <= 0x7F)

    {

        pb_byte_t v = (pb_byte_t)value;

        return pb_write(stream, &v, 1);

    }

    while (value)

    {

        buffer[i] = (pb_byte_t)((value & 0x7F) | 0x80);

        value >>= 7;

        i++;

    }

    buffer[i-1] &= 0x7F; /* Unset top bit on last byte */

    return pb_write(stream, buffer, i);

}

bool checkreturn pb_encode_svarint(pb_ostream_t *stream, pb_int64_t value)

{

    pb_uint64_t zigzagged;

    if (value < 0)

        zigzagged = ~((pb_uint64_t)value << 1);

    else

        zigzagged = (pb_uint64_t)value << 1;

    return pb_encode_varint(stream, zigzagged);

}

bool checkreturn pb_encode_fixed32(pb_ostream_t *stream, const void *value)

{

    uint32_t val = *(const uint32_t*)value;

    pb_byte_t bytes[4];

    bytes[0] = (pb_byte_t)(val & 0xFF);

    bytes[1] = (pb_byte_t)((val >> 8) & 0xFF);

    bytes[2] = (pb_byte_t)((val >> 16) & 0xFF);

    bytes[3] = (pb_byte_t)((val >> 24) & 0xFF);

    return pb_write(stream, bytes, 4);

}

#ifndef PB_WITHOUT_64BIT

bool checkreturn pb_encode_fixed64(pb_ostream_t *stream, const void *value)

{

    uint64_t val = *(const uint64_t*)value;

    pb_byte_t bytes[8];

    bytes[0] = (pb_byte_t)(val & 0xFF);

    bytes[1] = (pb_byte_t)((val >> 8) & 0xFF);

    bytes[2] = (pb_byte_t)((val >> 16) & 0xFF);

    bytes[3] = (pb_byte_t)((val >> 24) & 0xFF);

    bytes[4] = (pb_byte_t)((val >> 32) & 0xFF);

    bytes[5] = (pb_byte_t)((val >> 40) & 0xFF);

    bytes[6] = (pb_byte_t)((val >> 48) & 0xFF);

    bytes[7] = (pb_byte_t)((val >> 56) & 0xFF);

    return pb_write(stream, bytes, 8);

}

#endif

bool checkreturn pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, uint32_t field_number)

{

    pb_uint64_t tag = ((pb_uint64_t)field_number << 3) | wiretype;

    return pb_encode_varint(stream, tag);

}

bool checkreturn pb_encode_tag_for_field(pb_ostream_t *stream, const pb_field_t *field)

{

    pb_wire_type_t wiretype;

    switch (PB_LTYPE(field->type))

    {

        case PB_LTYPE_BOOL:

        case PB_LTYPE_VARINT:

        case PB_LTYPE_UVARINT:

        case PB_LTYPE_SVARINT:

            wiretype = PB_WT_VARINT;

            break;

        case PB_LTYPE_FIXED32:

            wiretype = PB_WT_32BIT;

            break;

        case PB_LTYPE_FIXED64:

            wiretype = PB_WT_64BIT;

            break;

        case PB_LTYPE_BYTES:

        case PB_LTYPE_STRING:

        case PB_LTYPE_SUBMESSAGE:

        case PB_LTYPE_FIXED_LENGTH_BYTES:

            wiretype = PB_WT_STRING;

            break;

        default:

            PB_RETURN_ERROR(stream, "invalid field type");

    }

    return pb_encode_tag(stream, wiretype, field->tag);

}

bool checkreturn pb_encode_string(pb_ostream_t *stream, const pb_byte_t *buffer, size_t size)

{

    if (!pb_encode_varint(stream, (pb_uint64_t)size))

        return false;

    return pb_write(stream, buffer, size);

}

bool checkreturn pb_encode_submessage(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)

{

    /* First calculate the message size using a non-writing substream. */

    pb_ostream_t substream = PB_OSTREAM_SIZING;

    size_t size;

    bool status;

    if (!pb_encode(&substream, fields, src_struct))

    {

#ifndef PB_NO_ERRMSG

        stream->errmsg = substream.errmsg;

#endif

        return false;

    }

    size = substream.bytes_written;

    if (!pb_encode_varint(stream, (pb_uint64_t)size))

        return false;

    if (stream->callback == NULL)

        return pb_write(stream, NULL, size); /* Just sizing */

    if (stream->bytes_written + size > stream->max_size)

        PB_RETURN_ERROR(stream, "stream full");

    /* Use a substream to verify that a callback doesn't write more than

     * what it did the first time. */

    substream.callback = stream->callback;

    substream.state = stream->state;

    substream.max_size = size;

    substream.bytes_written = 0;

#ifndef PB_NO_ERRMSG

    substream.errmsg = NULL;

#endif

    status = pb_encode(&substream, fields, src_struct);

    stream->bytes_written += substream.bytes_written;

    stream->state = substream.state;

#ifndef PB_NO_ERRMSG

    stream->errmsg = substream.errmsg;

#endif

    if (substream.bytes_written != size)

        PB_RETURN_ERROR(stream, "submsg size changed");

    return status;

}

/* Field encoders */

static bool checkreturn pb_enc_bool(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    uint32_t value = safe_read_bool(src) ? 1 : 0;

    PB_UNUSED(field);

    return pb_encode_varint(stream, value);

}

static bool checkreturn pb_enc_varint(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    pb_int64_t value = 0;

    if (field->data_size == sizeof(int_least8_t))

        value = *(const int_least8_t*)src;

    else if (field->data_size == sizeof(int_least16_t))

        value = *(const int_least16_t*)src;

    else if (field->data_size == sizeof(int32_t))

        value = *(const int32_t*)src;

    else if (field->data_size == sizeof(pb_int64_t))

        value = *(const pb_int64_t*)src;

    else

        PB_RETURN_ERROR(stream, "invalid data_size");

#ifdef PB_WITHOUT_64BIT

    if (value < 0)

      return pb_encode_negative_varint(stream, (pb_uint64_t)value);

    else

#endif

      return pb_encode_varint(stream, (pb_uint64_t)value);

}

static bool checkreturn pb_enc_uvarint(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    pb_uint64_t value = 0;

    if (field->data_size == sizeof(uint_least8_t))

        value = *(const uint_least8_t*)src;

    else if (field->data_size == sizeof(uint_least16_t))

        value = *(const uint_least16_t*)src;

    else if (field->data_size == sizeof(uint32_t))

        value = *(const uint32_t*)src;

    else if (field->data_size == sizeof(pb_uint64_t))

        value = *(const pb_uint64_t*)src;

    else

        PB_RETURN_ERROR(stream, "invalid data_size");

    return pb_encode_varint(stream, value);

}

static bool checkreturn pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    pb_int64_t value = 0;

    if (field->data_size == sizeof(int_least8_t))

        value = *(const int_least8_t*)src;

    else if (field->data_size == sizeof(int_least16_t))

        value = *(const int_least16_t*)src;

    else if (field->data_size == sizeof(int32_t))

        value = *(const int32_t*)src;

    else if (field->data_size == sizeof(pb_int64_t))

        value = *(const pb_int64_t*)src;

    else

        PB_RETURN_ERROR(stream, "invalid data_size");

    return pb_encode_svarint(stream, value);

}

static bool checkreturn pb_enc_fixed64(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    PB_UNUSED(field);

#ifndef PB_WITHOUT_64BIT

    return pb_encode_fixed64(stream, src);

#else

    PB_UNUSED(src);

    PB_RETURN_ERROR(stream, "no 64bit support");

#endif

}

static bool checkreturn pb_enc_fixed32(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    PB_UNUSED(field);

    return pb_encode_fixed32(stream, src);

}

static bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    const pb_bytes_array_t *bytes = NULL;

    size_t allocsize;

    bytes = (const pb_bytes_array_t*)src;

    if (src == NULL)

    {

        /* Treat null pointer as an empty bytes field */

        return pb_encode_string(stream, NULL, 0);

    }

    allocsize = PB_BYTES_ARRAY_T_ALLOCSIZE(bytes->size);

    if (allocsize < bytes->size ||

        (PB_ATYPE(field->type) == PB_ATYPE_STATIC && allocsize > field->data_size))

    {

        PB_RETURN_ERROR(stream, "bytes size exceeded");

    }

    return pb_encode_string(stream, bytes->bytes, bytes->size);

}

static bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    size_t size = 0;

    size_t max_size = field->data_size;

    const char *p = (const char*)src;

    if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)

        max_size = (size_t)-1;

    if (src == NULL)

    {

        size = 0; /* Treat null pointer as an empty string */

    }

    else

    {

        /* strnlen() is not always available, so just use a loop */

        while (size < max_size && *p != '\0')

        {

            size++;

            p++;

        }

    }

    return pb_encode_string(stream, (const pb_byte_t*)src, size);

}

static bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    if (field->ptr == NULL)

        PB_RETURN_ERROR(stream, "invalid field descriptor");

    return pb_encode_submessage(stream, (const pb_field_t*)field->ptr, src);

}

static bool checkreturn pb_enc_fixed_length_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src)

{

    return pb_encode_string(stream, (const pb_byte_t*)src, field->data_size);

}