dsutils.c

acpi tools for linux include acpiexec and acpixtract

        case AML_WHILE_OP:

            /*
             * If we are executing the predicate AND this is the predicate op,
             * we will use the return value
             */
            if ((WalkState->ControlState->Common.State == ACPI_CONTROL_PREDICATE_EXECUTING) &&
                (WalkState->ControlState->Control.PredicateOp == Op))
            {
                goto ResultUsed;
            }
            break;

        default:
            /* Ignore other control opcodes */
            break;
        }

        /* The general control opcode returns no result */

        goto ResultNotUsed;


    case AML_CLASS_CREATE:

        /*
         * These opcodes allow TermArg(s) as operands and therefore
         * the operands can be method calls.  The result is used.
         */
        goto ResultUsed;


    case AML_CLASS_NAMED_OBJECT:

        if ((Op->Common.Parent->Common.AmlOpcode == AML_REGION_OP)       ||
            (Op->Common.Parent->Common.AmlOpcode == AML_DATA_REGION_OP)  ||
            (Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP)      ||
            (Op->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP)  ||
            (Op->Common.Parent->Common.AmlOpcode == AML_BUFFER_OP)       ||
            (Op->Common.Parent->Common.AmlOpcode == AML_INT_EVAL_SUBTREE_OP) ||
            (Op->Common.Parent->Common.AmlOpcode == AML_BANK_FIELD_OP))
        {
            /*
             * These opcodes allow TermArg(s) as operands and therefore
             * the operands can be method calls.  The result is used.
             */
            goto ResultUsed;
        }

        goto ResultNotUsed;


    default:

        /*
         * In all other cases. the parent will actually use the return
         * object, so keep it.
         */
        goto ResultUsed;
    }


ResultUsed:
    ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
        "Result of [%s] used by Parent [%s] Op=%p\n",
        AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
        AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));

    return_UINT8 (TRUE);


ResultNotUsed:
    ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
        "Result of [%s] not used by Parent [%s] Op=%p\n",
        AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
        AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));

    return_UINT8 (FALSE);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiDsDeleteResultIfNotUsed
 *
 * PARAMETERS:  Op              - Current parse Op
 *              ResultObj       - Result of the operation
 *              WalkState       - Current state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Used after interpretation of an opcode.  If there is an internal
 *              result descriptor, check if the parent opcode will actually use
 *              this result.  If not, delete the result now so that it will
 *              not become orphaned.
 *
 ******************************************************************************/

void
AcpiDsDeleteResultIfNotUsed (
    ACPI_PARSE_OBJECT       *Op,
    ACPI_OPERAND_OBJECT     *ResultObj,
    ACPI_WALK_STATE         *WalkState)
{
    ACPI_OPERAND_OBJECT     *ObjDesc;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE_PTR (DsDeleteResultIfNotUsed, ResultObj);


    if (!Op)
    {
        ACPI_ERROR ((AE_INFO, "Null Op"));
        return_VOID;
    }

    if (!ResultObj)
    {
        return_VOID;
    }

    if (!AcpiDsIsResultUsed (Op, WalkState))
    {
        /* Must pop the result stack (ObjDesc should be equal to ResultObj) */

        Status = AcpiDsResultPop (&ObjDesc, WalkState);
        if (ACPI_SUCCESS (Status))
        {
            AcpiUtRemoveReference (ResultObj);
        }
    }

    return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiDsResolveOperands
 *
 * PARAMETERS:  WalkState           - Current walk state with operands on stack
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Resolve all operands to their values.  Used to prepare
 *              arguments to a control method invocation (a call from one
 *              method to another.)
 *
 ******************************************************************************/

ACPI_STATUS
AcpiDsResolveOperands (
    ACPI_WALK_STATE         *WalkState)
{
    UINT32                  i;
    ACPI_STATUS             Status = AE_OK;


    ACPI_FUNCTION_TRACE_PTR (DsResolveOperands, WalkState);


    /*
     * Attempt to resolve each of the valid operands
     * Method arguments are passed by reference, not by value.  This means
     * that the actual objects are passed, not copies of the objects.
     */
    for (i = 0; i < WalkState->NumOperands; i++)
    {
        Status = AcpiExResolveToValue (&WalkState->Operands[i], WalkState);
        if (ACPI_FAILURE (Status))
        {
            break;
        }
    }

    return_ACPI_STATUS (Status);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiDsClearOperands
 *
 * PARAMETERS:  WalkState           - Current walk state with operands on stack
 *
 * RETURN:      None
 *
 * DESCRIPTION: Clear all operands on the current walk state operand stack.
 *
 ******************************************************************************/

void
AcpiDsClearOperands (
    ACPI_WALK_STATE         *WalkState)
{
    UINT32                  i;


    ACPI_FUNCTION_TRACE_PTR (DsClearOperands, WalkState);


    /* Remove a reference on each operand on the stack */

    for (i = 0; i < WalkState->NumOperands; i++)
    {
        /*
         * Remove a reference to all operands, including both
         * "Arguments" and "Targets".
         */
        AcpiUtRemoveReference (WalkState->Operands[i]);
        WalkState->Operands[i] = NULL;
    }

    WalkState->NumOperands = 0;
    return_VOID;
}
#endif


/*******************************************************************************
 *
 * FUNCTION:    AcpiDsCreateOperand
 *
 * PARAMETERS:  WalkState       - Current walk state
 *              Arg             - Parse object for the argument
 *              ArgIndex        - Which argument (zero based)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Translate a parse tree object that is an argument to an AML
 *              opcode to the equivalent interpreter object.  This may include
 *              looking up a name or entering a new name into the internal
 *              namespace.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiDsCreateOperand (
    ACPI_WALK_STATE         *WalkState,
    ACPI_PARSE_OBJECT       *Arg,
    UINT32                  ArgIndex)
{
    ACPI_STATUS             Status = AE_OK;
    char                    *NameString;
    UINT32                  NameLength;
    ACPI_OPERAND_OBJECT     *ObjDesc;
    ACPI_PARSE_OBJECT       *ParentOp;
    UINT16                  Opcode;
    ACPI_INTERPRETER_MODE   InterpreterMode;
    const ACPI_OPCODE_INFO  *OpInfo;


    ACPI_FUNCTION_TRACE_PTR (DsCreateOperand, Arg);


    /* A valid name must be looked up in the namespace */

    if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
        (Arg->Common.Value.String) &&
        !(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
    {
        ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n", Arg));

        /* Get the entire name string from the AML stream */

        Status = AcpiExGetNameString (ACPI_TYPE_ANY, Arg->Common.Value.Buffer,
                        &NameString, &NameLength);

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

        /* All prefixes have been handled, and the name is in NameString */

        /*
         * Special handling for BufferField declarations.  This is a deferred
         * opcode that unfortunately defines the field name as the last
         * parameter instead of the first.  We get here when we are performing
         * the deferred execution, so the actual name of the field is already
         * in the namespace.  We don't want to attempt to look it up again
         * because we may be executing in a different scope than where the
         * actual opcode exists.
         */
        if ((WalkState->DeferredNode) &&
            (WalkState->DeferredNode->Type == ACPI_TYPE_BUFFER_FIELD) &&
            (ArgIndex == (UINT32) ((WalkState->Opcode == AML_CREATE_FIELD_OP) ? 3 : 2)))
        {
            ObjDesc = ACPI_CAST_PTR (
                        ACPI_OPERAND_OBJECT, WalkState->DeferredNode);
            Status = AE_OK;
        }
        else    /* All other opcodes */
        {
            /*
             * Differentiate between a namespace "create" operation
             * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
             * IMODE_EXECUTE) in order to support the creation of
             * namespace objects during the execution of control methods.
             */
            ParentOp = Arg->Common.Parent;
            OpInfo = AcpiPsGetOpcodeInfo (ParentOp->Common.AmlOpcode);
            if ((OpInfo->Flags & AML_NSNODE) &&
                (ParentOp->Common.AmlOpcode != AML_INT_METHODCALL_OP) &&
                (ParentOp->Common.AmlOpcode != AML_REGION_OP) &&
                (ParentOp->Common.AmlOpcode != AML_INT_NAMEPATH_OP))
            {
                /* Enter name into namespace if not found */

                InterpreterMode = ACPI_IMODE_LOAD_PASS2;
            }
            else
            {
                /* Return a failure if name not found */

                InterpreterMode = ACPI_IMODE_EXECUTE;
            }

            Status = AcpiNsLookup (WalkState->ScopeInfo, NameString,
                        ACPI_TYPE_ANY, InterpreterMode,
                        ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
                        WalkState,
                        ACPI_CAST_INDIRECT_PTR (ACPI_NAMESPACE_NODE, &ObjDesc));
            /*
             * The only case where we pass through (ignore) a NOT_FOUND
             * error is for the CondRefOf opcode.
             */
            if (Status == AE_NOT_FOUND)
            {
                if (ParentOp->Common.AmlOpcode == AML_COND_REF_OF_OP)
                {
                    /*
                     * For the Conditional Reference op, it's OK if
                     * the name is not found;  We just need a way to
                     * indicate this to the interpreter, set the
                     * object to the root