exoparg1.c

acpi tools for linux include acpiexec and acpixtract

        /*
         * TempDesc is now guaranteed to be an Integer object --
         * Perform the actual increment or decrement
         */
        if (WalkState->Opcode == AML_INCREMENT_OP)
        {
            ReturnDesc->Integer.Value = TempDesc->Integer.Value +1;
        }
        else
        {
            ReturnDesc->Integer.Value = TempDesc->Integer.Value -1;
        }

        /* Finished with this Integer object */

        AcpiUtRemoveReference (TempDesc);

        /*
         * Store the result back (indirectly) through the original
         * Reference object
         */
        Status = AcpiExStore (ReturnDesc, Operand[0], WalkState);
        break;


    case AML_TYPE_OP:               /* ObjectType (SourceObject) */

        /*
         * Note: The operand is not resolved at this point because we want to
         * get the associated object, not its value.  For example, we don't
         * want to resolve a FieldUnit to its value, we want the actual
         * FieldUnit object.
         */

        /* Get the type of the base object */

        Status = AcpiExResolveMultiple (WalkState, Operand[0], &Type, NULL);
        if (ACPI_FAILURE (Status))
        {
            goto Cleanup;
        }

        /* Allocate a descriptor to hold the type. */

        ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
        if (!ReturnDesc)
        {
            Status = AE_NO_MEMORY;
            goto Cleanup;
        }

        ReturnDesc->Integer.Value = Type;
        break;


    case AML_SIZE_OF_OP:            /* SizeOf (SourceObject)  */

        /*
         * Note: The operand is not resolved at this point because we want to
         * get the associated object, not its value.
         */

        /* Get the base object */

        Status = AcpiExResolveMultiple (WalkState,
                    Operand[0], &Type, &TempDesc);
        if (ACPI_FAILURE (Status))
        {
            goto Cleanup;
        }

        /*
         * The type of the base object must be integer, buffer, string, or
         * package.  All others are not supported.
         *
         * NOTE: Integer is not specifically supported by the ACPI spec,
         * but is supported implicitly via implicit operand conversion.
         * rather than bother with conversion, we just use the byte width
         * global (4 or 8 bytes).
         */
        switch (Type)
        {
        case ACPI_TYPE_INTEGER:
            Value = AcpiGbl_IntegerByteWidth;
            break;

        case ACPI_TYPE_STRING:
            Value = TempDesc->String.Length;
            break;

        case ACPI_TYPE_BUFFER:

            /* Buffer arguments may not be evaluated at this point */

            Status = AcpiDsGetBufferArguments (TempDesc);
            Value = TempDesc->Buffer.Length;
            break;

        case ACPI_TYPE_PACKAGE:

            /* Package arguments may not be evaluated at this point */

            Status = AcpiDsGetPackageArguments (TempDesc);
            Value = TempDesc->Package.Count;
            break;

        default:
            ACPI_ERROR ((AE_INFO,
                "Operand must be Buffer/Integer/String/Package - found type %s",
                AcpiUtGetTypeName (Type)));
            Status = AE_AML_OPERAND_TYPE;
            goto Cleanup;
        }

        if (ACPI_FAILURE (Status))
        {
            goto Cleanup;
        }

        /*
         * Now that we have the size of the object, create a result
         * object to hold the value
         */
        ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
        if (!ReturnDesc)
        {
            Status = AE_NO_MEMORY;
            goto Cleanup;
        }

        ReturnDesc->Integer.Value = Value;
        break;


    case AML_REF_OF_OP:             /* RefOf (SourceObject) */

        Status = AcpiExGetObjectReference (Operand[0], &ReturnDesc, WalkState);
        if (ACPI_FAILURE (Status))
        {
            goto Cleanup;
        }
        break;


    case AML_DEREF_OF_OP:           /* DerefOf (ObjReference | String) */

        /* Check for a method local or argument, or standalone String */

        if (ACPI_GET_DESCRIPTOR_TYPE (Operand[0]) == ACPI_DESC_TYPE_NAMED)
        {
            TempDesc = AcpiNsGetAttachedObject (
                           (ACPI_NAMESPACE_NODE *) Operand[0]);
            if (TempDesc &&
                 ((ACPI_GET_OBJECT_TYPE (TempDesc) == ACPI_TYPE_STRING) ||
                  (ACPI_GET_OBJECT_TYPE (TempDesc) == ACPI_TYPE_LOCAL_REFERENCE)))
            {
                Operand[0] = TempDesc;
                AcpiUtAddReference (TempDesc);
            }
            else
            {
                Status = AE_AML_OPERAND_TYPE;
                goto Cleanup;
            }
        }
        else
        {
            switch (ACPI_GET_OBJECT_TYPE (Operand[0]))
            {
            case ACPI_TYPE_LOCAL_REFERENCE:
                /*
                 * This is a DerefOf (LocalX | ArgX)
                 *
                 * Must resolve/dereference the local/arg reference first
                 */
                switch (Operand[0]->Reference.Opcode)
                {
                case AML_LOCAL_OP:
                case AML_ARG_OP:

                    /* Set Operand[0] to the value of the local/arg */

                    Status = AcpiDsMethodDataGetValue (
                                Operand[0]->Reference.Opcode,
                                Operand[0]->Reference.Offset,
                                WalkState, &TempDesc);
                    if (ACPI_FAILURE (Status))
                    {
                        goto Cleanup;
                    }

                    /*
                     * Delete our reference to the input object and
                     * point to the object just retrieved
                     */
                    AcpiUtRemoveReference (Operand[0]);
                    Operand[0] = TempDesc;
                    break;

                case AML_REF_OF_OP:

                    /* Get the object to which the reference refers */

                    TempDesc = Operand[0]->Reference.Object;
                    AcpiUtRemoveReference (Operand[0]);
                    Operand[0] = TempDesc;
                    break;

                default:

                    /* Must be an Index op - handled below */
                    break;
                }
                break;

            case ACPI_TYPE_STRING:
                break;

            default:
                Status = AE_AML_OPERAND_TYPE;
                goto Cleanup;
            }
        }

        if (ACPI_GET_DESCRIPTOR_TYPE (Operand[0]) != ACPI_DESC_TYPE_NAMED)
        {
            if (ACPI_GET_OBJECT_TYPE (Operand[0]) == ACPI_TYPE_STRING)
            {
                /*
                 * This is a DerefOf (String). The string is a reference
                 * to a named ACPI object.
                 *
                 * 1) Find the owning Node
                 * 2) Dereference the node to an actual object. Could be a
                 *    Field, so we need to resolve the node to a value.
                 */
                Status = AcpiNsGetNode (WalkState->ScopeInfo->Scope.Node,
                            Operand[0]->String.Pointer,
                            ACPI_NS_SEARCH_PARENT,
                            ACPI_CAST_INDIRECT_PTR (
                                ACPI_NAMESPACE_NODE, &ReturnDesc));
                if (ACPI_FAILURE (Status))
                {
                    goto Cleanup;
                }

                Status = AcpiExResolveNodeToValue (
                            ACPI_CAST_INDIRECT_PTR (
                                ACPI_NAMESPACE_NODE, &ReturnDesc),
                            WalkState);
                goto Cleanup;
            }
        }

        /* Operand[0] may have changed from the code above */

        if (ACPI_GET_DESCRIPTOR_TYPE (Operand[0]) == ACPI_DESC_TYPE_NAMED)
        {
            /*
             * This is a DerefOf (ObjectReference)
             * Get the actual object from the Node (This is the dereference).
             * This case may only happen when a LocalX or ArgX is
             * dereferenced above.
             */
            ReturnDesc = AcpiNsGetAttachedObject (
                            (ACPI_NAMESPACE_NODE *) Operand[0]);
            AcpiUtAddReference (ReturnDesc);
        }
        else
        {
            /*
             * This must be a reference object produced by either the
             * Index() or RefOf() operator
             */
            switch (Operand[0]->Reference.Opcode)
            {
            case AML_INDEX_OP:

                /*
                 * The target type for the Index operator must be
                 * either a Buffer or a Package
                 */
                switch (Operand[0]->Reference.TargetType)
                {
                case ACPI_TYPE_BUFFER_FIELD:

                    TempDesc = Operand[0]->Reference.Object;

                    /*
                     * Create a new object that contains one element of the
                     * buffer -- the element pointed to by the index.
                     *
                     * NOTE: index into a buffer is NOT a pointer to a
                     * sub-buffer of the main buffer, it is only a pointer to a
                     * single element (byte) of the buffer!
                     */
                    ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
                    if (!ReturnDesc)
                    {
                        Status = AE_NO_MEMORY;
                        goto Cleanup;
                    }

                    /*
                     * Since we are returning the value of the buffer at the
                     * indexed location, we don't need to add an additional
                     * reference to the buffer itself.
                     */
                    ReturnDesc->Integer.Value =
                        TempDesc->Buffer.Pointer[Operand[0]->Reference.Offset];
                    break;


                case ACPI_TYPE_PACKAGE:

                    /*
                     * Return the referenced element of the package.  We must
                     * add another reference to the referenced object, however.
                     */
                    ReturnDesc = *(Operand[0]->Reference.Where);
                    if (ReturnDesc)
                    {
                        AcpiUtAddReference (ReturnDesc);
                    }
                    break;


                default:

                    ACPI_ERROR ((AE_INFO,
                        "Unknown Index TargetType %X in obj %p",
                        Operand[0]->Reference.TargetType, Operand[0]));
                    Status = AE_AML_OPERAND_TYPE;
                    goto Cleanup;
                }
                break;


            case AML_REF_OF_OP:

                ReturnDesc = Operand[0]->Reference.Object;

                if (ACPI_GET_DESCRIPTOR_TYPE (ReturnDesc) ==
                        ACPI_DESC_TYPE_NAMED)
                {
                    ReturnDesc = AcpiNsGetAttachedObject (
                                    (ACPI_NAMESPACE_NODE *) ReturnDesc);
                }

                /* Add another reference to the object! */

                AcpiUtAddReference (ReturnDesc);
                break;


            default:
                ACPI_ERROR ((AE_INFO,
                    "Unknown opcode in reference(%p) - %X",
                    Operand[0], Operand[0]->Reference.Opcode));

                Status = AE_TYPE;
                goto Cleanup;
            }
        }
        break;


    default:

        ACPI_ERROR ((AE_INFO, "Unknown AML opcode %X",
            WalkState->Opcode));
        Status = AE_AML_BAD_OPCODE;
        goto Cleanup;
    }


Cleanup:

    /* Delete return object on error */

    if (ACPI_FAILURE (Status))
    {
        AcpiUtRemoveReference (ReturnDesc);
    }

    /* Save return object on success */

    else
    {
        WalkState->ResultObj = ReturnDesc;
    }

    return_ACPI_STATUS (Status);
}