CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT CONSTBUFFER_to_fixed_size_buffer()

in src/constbuffer.c [535:588]

• 39 lines of code
• 6 McCabe index (conditional complexity)

CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT CONSTBUFFER_to_fixed_size_buffer(CONSTBUFFER_HANDLE source, unsigned char* destination, uint32_t destination_size, uint32_t* serialized_size)
{
    CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT result;
    
    if (
        /*Codes_SRS_CONSTBUFFER_02_055: [ If source is NULL then CONSTBUFFER_to_fixed_size_buffer shall fail and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INVALID_ARG. ]*/
        (source == NULL) ||
        /*Codes_SRS_CONSTBUFFER_02_056: [ If destination is NULL then CONSTBUFFER_to_fixed_size_buffer shall fail and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INVALID_ARG. ]*/
        (destination == NULL) ||
        /*Codes_SRS_CONSTBUFFER_02_057: [ If serialized_size is NULL then CONSTBUFFER_to_fixed_size_buffer shall fail and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INVALID_ARG. ]*/
        (serialized_size == NULL)
        )
    {
        LogError("invalid arguments CONSTBUFFER_HANDLE source=%p, unsigned char* destination=%p, uint32_t destination_size=%" PRIu32 ", uint32_t* serialized_size=%p",
            source, destination, destination_size, serialized_size);
        result = CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INVALID_ARG;
    }
    else
    {
        if (UINT32_MAX - (CONSTBUFFER_VERSION_SIZE + CONSTBUFFER_SIZE_SIZE) < source->alias.size)
        {
            /*when this is true, an output for "serialized_size" cannot be provided as the complete serialization would exceed UINT32_MAX*/
            LogError("overflow in computation of output parameter serialized_size");

            /*Codes_SRS_CONSTBUFFER_02_074: [ If there are any failures then CONSTBUFFER_to_fixed_size_buffer shall fail and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_ERROR. ]*/
            result = CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_ERROR;
        }
        else
        {
            *serialized_size = CONSTBUFFER_VERSION_SIZE + CONSTBUFFER_SIZE_SIZE + (uint32_t)source->alias.size;
            /*Codes_SRS_CONSTBUFFER_02_058: [ If the size of serialization exceeds destination_size then CONSTBUFFER_to_fixed_size_buffer shall fail, write in serialized_size how much it would need and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INSUFFICIENT_BUFFER. ]*/
            if (destination_size < *serialized_size)
            {
                LogError("destination=%p does not contain enough bytes for the complete serialization. It only has %" PRIu32 " bytes and there are needed %" PRIu32 " bytes", destination, destination_size, *serialized_size);
                result = CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_INSUFFICIENT_BUFFER;
            }
            else
            {
                /*Codes_SRS_CONSTBUFFER_02_059: [ CONSTBUFFER_to_fixed_size_buffer shall write at offset 0 of destination the version of serialization (currently 1). ]*/
                write_uint8_t(destination + CONSTBUFFER_VERSION_OFFSET, CONSTBUFFER_VERSION_V1);

                /*Codes_SRS_CONSTBUFFER_02_060: [ CONSTBUFFER_to_fixed_size_buffer shall write at offset 1 of destination the value of source->alias.size in network byte order. ]*/
                write_uint32_t(destination + CONSTBUFFER_SIZE_OFFSET, (uint32_t)source->alias.size);

                /*Codes_SRS_CONSTBUFFER_02_061: [ CONSTBUFFER_to_fixed_size_buffer shall copy all the bytes of source->alias.buffer in destination starting at offset 5. ]*/
                (void)memcpy(destination + CONSTBUFFER_CONTENT_OFFSET, source->alias.buffer, source->alias.size);

                /*Codes_SRS_CONSTBUFFER_02_062: [ CONSTBUFFER_to_fixed_size_buffer shall succeed, write in serialized_size how much it used and return CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_OK. ]*/
                result = CONSTBUFFER_TO_FIXED_SIZE_BUFFER_RESULT_OK;
            }
        }
    }
    return result;
}