dsutils.c

acpi tools for linux include acpiexec and acpixtract

                     */
                    ObjDesc = ACPI_CAST_PTR (
                                ACPI_OPERAND_OBJECT, AcpiGbl_RootNode);
                    Status = AE_OK;
                }
                else
                {
                    /*
                     * We just plain didn't find it -- which is a
                     * very serious error at this point
                     */
                    Status = AE_AML_NAME_NOT_FOUND;
                }
            }

            if (ACPI_FAILURE (Status))
            {
                ACPI_ERROR_NAMESPACE (NameString, Status);
            }
        }

        /* Free the namestring created above */

        ACPI_FREE (NameString);

        /* Check status from the lookup */

        if (ACPI_FAILURE (Status))
        {
            return_ACPI_STATUS (Status);
        }

        /* Put the resulting object onto the current object stack */

        Status = AcpiDsObjStackPush (ObjDesc, WalkState);
        if (ACPI_FAILURE (Status))
        {
            return_ACPI_STATUS (Status);
        }
        ACPI_DEBUGGER_EXEC (AcpiDbDisplayArgumentObject (ObjDesc, WalkState));
    }
    else
    {
        /* Check for null name case */

        if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
            !(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
        {
            /*
             * If the name is null, this means that this is an
             * optional result parameter that was not specified
             * in the original ASL.  Create a Zero Constant for a
             * placeholder.  (Store to a constant is a Noop.)
             */
            Opcode = AML_ZERO_OP;       /* Has no arguments! */

            ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
                "Null namepath: Arg=%p\n", Arg));
        }
        else
        {
            Opcode = Arg->Common.AmlOpcode;
        }

        /* Get the object type of the argument */

        OpInfo = AcpiPsGetOpcodeInfo (Opcode);
        if (OpInfo->ObjectType == ACPI_TYPE_INVALID)
        {
            return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
        }

        if ((OpInfo->Flags & AML_HAS_RETVAL) || (Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
        {
            ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
                "Argument previously created, already stacked\n"));

            ACPI_DEBUGGER_EXEC (AcpiDbDisplayArgumentObject (
                WalkState->Operands [WalkState->NumOperands - 1], WalkState));

            /*
             * Use value that was already previously returned
             * by the evaluation of this argument
             */
            Status = AcpiDsResultPop (&ObjDesc, WalkState);
            if (ACPI_FAILURE (Status))
            {
                /*
                 * Only error is underflow, and this indicates
                 * a missing or null operand!
                 */
                ACPI_EXCEPTION ((AE_INFO, Status,
                    "Missing or null operand"));
                return_ACPI_STATUS (Status);
            }
        }
        else
        {
            /* Create an ACPI_INTERNAL_OBJECT for the argument */

            ObjDesc = AcpiUtCreateInternalObject (OpInfo->ObjectType);
            if (!ObjDesc)
            {
                return_ACPI_STATUS (AE_NO_MEMORY);
            }

            /* Initialize the new object */

            Status = AcpiDsInitObjectFromOp (
                        WalkState, Arg, Opcode, &ObjDesc);
            if (ACPI_FAILURE (Status))
            {
                AcpiUtDeleteObjectDesc (ObjDesc);
                return_ACPI_STATUS (Status);
            }
        }

        /* Put the operand object on the object stack */

        Status = AcpiDsObjStackPush (ObjDesc, WalkState);
        if (ACPI_FAILURE (Status))
        {
            return_ACPI_STATUS (Status);
        }

        ACPI_DEBUGGER_EXEC (AcpiDbDisplayArgumentObject (ObjDesc, WalkState));
    }

    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiDsCreateOperands
 *
 * PARAMETERS:  WalkState           - Current state
 *              FirstArg            - First argument of a parser argument tree
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an operator's arguments from a parse tree format to
 *              namespace objects and place those argument object on the object
 *              stack in preparation for evaluation by the interpreter.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiDsCreateOperands (
    ACPI_WALK_STATE         *WalkState,
    ACPI_PARSE_OBJECT       *FirstArg)
{
    ACPI_STATUS             Status = AE_OK;
    ACPI_PARSE_OBJECT       *Arg;
    ACPI_PARSE_OBJECT       *Arguments[ACPI_OBJ_NUM_OPERANDS];
    UINT32                  ArgCount = 0;
    UINT32                  Index = WalkState->NumOperands;
    UINT32                  i;


    ACPI_FUNCTION_TRACE_PTR (DsCreateOperands, FirstArg);


    /* Get all arguments in the list */

    Arg = FirstArg;
    while (Arg)
    {
        if (Index >= ACPI_OBJ_NUM_OPERANDS)
        {
            return_ACPI_STATUS (AE_BAD_DATA);
        }

        Arguments[Index] = Arg;
        WalkState->Operands [Index] = NULL;

        /* Move on to next argument, if any */

        Arg = Arg->Common.Next;
        ArgCount++;
        Index++;
    }

    Index--;

    /* It is the appropriate order to get objects from the Result stack */

    for (i = 0; i < ArgCount; i++)
    {
        Arg = Arguments[Index];

        /* Force the filling of the operand stack in inverse order */

        WalkState->OperandIndex = (UINT8) Index;

        Status = AcpiDsCreateOperand (WalkState, Arg, Index);
        if (ACPI_FAILURE (Status))
        {
            goto Cleanup;
        }

        Index--;

        ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Arg #%d (%p) done, Arg1=%p\n",
            Index, Arg, FirstArg));
    }

    return_ACPI_STATUS (Status);


Cleanup:
    /*
     * We must undo everything done above; meaning that we must
     * pop everything off of the operand stack and delete those
     * objects
     */
    AcpiDsObjStackPopAndDelete (ArgCount, WalkState);

    ACPI_EXCEPTION ((AE_INFO, Status, "While creating Arg %d", Index));
    return_ACPI_STATUS (Status);
}


/*****************************************************************************
 *
 * FUNCTION:    AcpiDsEvaluateNamePath
 *
 * PARAMETERS:  WalkState       - Current state of the parse tree walk,
 *                                the opcode of current operation should be
 *                                AML_INT_NAMEPATH_OP
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Translate the -NamePath- parse tree object to the equivalent
 *              interpreter object, convert it to value, if needed, duplicate
 *              it, if needed, and push it onto the current result stack.
 *
 ****************************************************************************/

ACPI_STATUS
AcpiDsEvaluateNamePath (
    ACPI_WALK_STATE         *WalkState)
{
    ACPI_STATUS             Status = AE_OK;
    ACPI_PARSE_OBJECT       *Op = WalkState->Op;
    ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
    ACPI_OPERAND_OBJECT     *NewObjDesc;
    UINT8                   Type;


    ACPI_FUNCTION_TRACE_PTR (DsEvaluateNamePath, WalkState);


    if (!Op->Common.Parent)
    {
        /* This happens after certain exception processing */

        goto Exit;
    }

    if ((Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
        (Op->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP) ||
        (Op->Common.Parent->Common.AmlOpcode == AML_REF_OF_OP))
    {
        /* TBD: Should we specify this feature as a bit of OpInfo->Flags of these opcodes? */

        goto Exit;
    }

    Status = AcpiDsCreateOperand (WalkState, Op, 0);
    if (ACPI_FAILURE (Status))
    {
        goto Exit;
    }

    if (Op->Common.Flags & ACPI_PARSEOP_TARGET)
    {
        NewObjDesc = *Operand;
        goto PushResult;
    }

    Type = ACPI_GET_OBJECT_TYPE (*Operand);

    Status = AcpiExResolveToValue (Operand, WalkState);
    if (ACPI_FAILURE (Status))
    {
        goto Exit;
    }

    if (Type == ACPI_TYPE_INTEGER)
    {
        /* It was incremented by AcpiExResolveToValue */

        AcpiUtRemoveReference (*Operand);

        Status = AcpiUtCopyIobjectToIobject (*Operand, &NewObjDesc, WalkState);
        if (ACPI_FAILURE (Status))
        {
            goto Exit;
        }
    }
    else
    {
        /*
         * The object either was anew created or is
         * a Namespace node - don't decrement it.
         */
        NewObjDesc = *Operand;
    }

    /* Cleanup for name-path operand */

    Status = AcpiDsObjStackPop (1, WalkState);
    if (ACPI_FAILURE (Status))
    {
        WalkState->ResultObj = NewObjDesc;
        goto Exit;
    }

PushResult:

    WalkState->ResultObj = NewObjDesc;

    Status = AcpiDsResultPush (WalkState->ResultObj, WalkState);
    if (ACPI_SUCCESS (Status))
    {
        /* Force to take it from stack */

        Op->Common.Flags |= ACPI_PARSEOP_IN_STACK;
    }

Exit:

    return_ACPI_STATUS (Status);
}