static ShadowStatus_t extractShadowMessageType()

in source/shadow.c [510:585]
64 lines of code
5 McCabe index (conditional complexity)

static ShadowStatus_t extractShadowMessageType( const char * pString,
                                                uint16_t stringLength,
                                                ShadowMessageType_t * pMessageType )
{
    uint32_t index = 0U;
    ShadowStatus_t returnStatus = SHADOW_FAIL;

    /* Lookup table for Shadow message string. */
    static const char * const pMessageStrings[ ShadowMessageTypeMaxNum ] =
    {
        SHADOW_OP_GET_ACCEPTED,
        SHADOW_OP_GET_REJECTED,
        SHADOW_OP_DELETE_ACCEPTED,
        SHADOW_OP_DELETE_REJECTED,
        SHADOW_OP_UPDATE_ACCEPTED,
        SHADOW_OP_UPDATE_REJECTED,
        SHADOW_OP_UPDATE_DOCUMENTS,
        SHADOW_OP_UPDATE_DELTA
    };

    /* Lookup table for Shadow message string length. */
    static const uint16_t pMessageStringsLength[ ShadowMessageTypeMaxNum ] =
    {
        SHADOW_OP_GET_ACCEPTED_LENGTH,
        SHADOW_OP_GET_REJECTED_LENGTH,
        SHADOW_OP_DELETE_ACCEPTED_LENGTH,
        SHADOW_OP_DELETE_REJECTED_LENGTH,
        SHADOW_OP_UPDATE_ACCEPTED_LENGTH,
        SHADOW_OP_UPDATE_REJECTED_LENGTH,
        SHADOW_OP_UPDATE_DOCUMENTS_LENGTH,
        SHADOW_OP_UPDATE_DELTA_LENGTH
    };

    /* Lookup table for Shadow message types. */
    static const ShadowMessageType_t pMessageTypes[ ShadowMessageTypeMaxNum ] =
    {
        ShadowMessageTypeGetAccepted,
        ShadowMessageTypeGetRejected,
        ShadowMessageTypeDeleteAccepted,
        ShadowMessageTypeDeleteRejected,
        ShadowMessageTypeUpdateAccepted,
        ShadowMessageTypeUpdateRejected,
        ShadowMessageTypeUpdateDocuments,
        ShadowMessageTypeUpdateDelta
    };

    for( ; index < ( uint32_t ) ( sizeof( pMessageStrings ) / sizeof( pMessageStrings[ 0 ] ) ); index++ )
    {
        returnStatus = containsSubString( pString,
                                          stringLength,
                                          pMessageStrings[ index ],
                                          pMessageStringsLength[ index ] );

        /* If the operation string matches, there must not be any other extra
         * character remaining in the string. */
        if( returnStatus == SHADOW_SUCCESS )
        {
            if( stringLength != pMessageStringsLength[ index ] )
            {
                returnStatus = SHADOW_FAIL;
            }
            else
            {
                *pMessageType = pMessageTypes[ index ];
                break;
            }
        }
    }

    if( returnStatus != SHADOW_SUCCESS )
    {
        LogDebug( ( "Not a Shadow topic. Failed to match shadow message type in pString %.*s", stringLength, pString ) );
    }

    return returnStatus;
}