psparse.c

acpi tools for linux include acpiexec and acpixtract

/******************************************************************************
 *
 * Module Name: psparse - Parser top level AML parse routines
 *              $Revision: 1.176 $
 *
 *****************************************************************************/

/******************************************************************************
 *
 * 1. Copyright Notice
 *
 * Some or all of this work - Copyright (c) 1999 - 2008, Intel Corp.
 * All rights reserved.
 *
 * 2. License
 *
 * 2.1. This is your license from Intel Corp. under its intellectual property
 * rights.  You may have additional license terms from the party that provided
 * you this software, covering your right to use that party's intellectual
 * property rights.
 *
 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
 * copy of the source code appearing in this file ("Covered Code") an
 * irrevocable, perpetual, worldwide license under Intel's copyrights in the
 * base code distributed originally by Intel ("Original Intel Code") to copy,
 * make derivatives, distribute, use and display any portion of the Covered
 * Code in any form, with the right to sublicense such rights; and
 *
 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
 * license (with the right to sublicense), under only those claims of Intel
 * patents that are infringed by the Original Intel Code, to make, use, sell,
 * offer to sell, and import the Covered Code and derivative works thereof
 * solely to the minimum extent necessary to exercise the above copyright
 * license, and in no event shall the patent license extend to any additions
 * to or modifications of the Original Intel Code.  No other license or right
 * is granted directly or by implication, estoppel or otherwise;
 *
 * The above copyright and patent license is granted only if the following
 * conditions are met:
 *
 * 3. Conditions
 *
 * 3.1. Redistribution of Source with Rights to Further Distribute Source.
 * Redistribution of source code of any substantial portion of the Covered
 * Code or modification with rights to further distribute source must include
 * the above Copyright Notice, the above License, this list of Conditions,
 * and the following Disclaimer and Export Compliance provision.  In addition,
 * Licensee must cause all Covered Code to which Licensee contributes to
 * contain a file documenting the changes Licensee made to create that Covered
 * Code and the date of any change.  Licensee must include in that file the
 * documentation of any changes made by any predecessor Licensee.  Licensee
 * must include a prominent statement that the modification is derived,
 * directly or indirectly, from Original Intel Code.
 *
 * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
 * Redistribution of source code of any substantial portion of the Covered
 * Code or modification without rights to further distribute source must
 * include the following Disclaimer and Export Compliance provision in the
 * documentation and/or other materials provided with distribution.  In
 * addition, Licensee may not authorize further sublicense of source of any
 * portion of the Covered Code, and must include terms to the effect that the
 * license from Licensee to its licensee is limited to the intellectual
 * property embodied in the software Licensee provides to its licensee, and
 * not to intellectual property embodied in modifications its licensee may
 * make.
 *
 * 3.3. Redistribution of Executable. Redistribution in executable form of any
 * substantial portion of the Covered Code or modification must reproduce the
 * above Copyright Notice, and the following Disclaimer and Export Compliance
 * provision in the documentation and/or other materials provided with the
 * distribution.
 *
 * 3.4. Intel retains all right, title, and interest in and to the Original
 * Intel Code.
 *
 * 3.5. Neither the name Intel nor any other trademark owned or controlled by
 * Intel shall be used in advertising or otherwise to promote the sale, use or
 * other dealings in products derived from or relating to the Covered Code
 * without prior written authorization from Intel.
 *
 * 4. Disclaimer and Export Compliance
 *
 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
 * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
 * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
 * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
 * PARTICULAR PURPOSE.
 *
 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
 * LIMITED REMEDY.
 *
 * 4.3. Licensee shall not export, either directly or indirectly, any of this
 * software or system incorporating such software without first obtaining any
 * required license or other approval from the U. S. Department of Commerce or
 * any other agency or department of the United States Government.  In the
 * event Licensee exports any such software from the United States or
 * re-exports any such software from a foreign destination, Licensee shall
 * ensure that the distribution and export/re-export of the software is in
 * compliance with all laws, regulations, orders, or other restrictions of the
 * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 * any of its subsidiaries will export/re-export any technical data, process,
 * software, or service, directly or indirectly, to any country for which the
 * United States government or any agency thereof requires an export license,
 * other governmental approval, or letter of assurance, without first obtaining
 * such license, approval or letter.
 *
 *****************************************************************************/


/*
 * Parse the AML and build an operation tree as most interpreters,
 * like Perl, do.  Parsing is done by hand rather than with a YACC
 * generated parser to tightly constrain stack and dynamic memory
 * usage.  At the same time, parsing is kept flexible and the code
 * fairly compact by parsing based on a list of AML opcode
 * templates in AmlOpInfo[]
 */

#include "acpi.h"
#include "acparser.h"
#include "acdispat.h"
#include "amlcode.h"
#include "acnamesp.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_PARSER
        ACPI_MODULE_NAME    ("psparse")


/*******************************************************************************
 *
 * FUNCTION:    AcpiPsGetOpcodeSize
 *
 * PARAMETERS:  Opcode          - An AML opcode
 *
 * RETURN:      Size of the opcode, in bytes (1 or 2)
 *
 * DESCRIPTION: Get the size of the current opcode.
 *
 ******************************************************************************/

UINT32
AcpiPsGetOpcodeSize (
    UINT32                  Opcode)
{

    /* Extended (2-byte) opcode if > 255 */

    if (Opcode > 0x00FF)
    {
        return (2);
    }

    /* Otherwise, just a single byte opcode */

    return (1);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiPsPeekOpcode
 *
 * PARAMETERS:  ParserState         - A parser state object
 *
 * RETURN:      Next AML opcode
 *
 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
 *
 ******************************************************************************/

UINT16
AcpiPsPeekOpcode (
    ACPI_PARSE_STATE        *ParserState)
{
    UINT8                   *Aml;
    UINT16                  Opcode;


    Aml = ParserState->Aml;
    Opcode = (UINT16) ACPI_GET8 (Aml);

    if (Opcode == AML_EXTENDED_OP_PREFIX)
    {
        /* Extended opcode, get the second opcode byte */

        Aml++;
        Opcode = (UINT16) ((Opcode << 8) | ACPI_GET8 (Aml));
    }

    return (Opcode);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiPsCompleteThisOp
 *
 * PARAMETERS:  WalkState       - Current State
 *              Op              - Op to complete
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform any cleanup at the completion of an Op.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiPsCompleteThisOp (
    ACPI_WALK_STATE         *WalkState,
    ACPI_PARSE_OBJECT       *Op)
{
    ACPI_PARSE_OBJECT       *Prev;
    ACPI_PARSE_OBJECT       *Next;
    const ACPI_OPCODE_INFO  *ParentInfo;
    ACPI_PARSE_OBJECT       *ReplacementOp = NULL;


    ACPI_FUNCTION_TRACE_PTR (PsCompleteThisOp, Op);


    /* Check for null Op, can happen if AML code is corrupt */

    if (!Op)
    {
        return_ACPI_STATUS (AE_OK);  /* OK for now */
    }

    /* Delete this op and the subtree below it if asked to */

    if (((WalkState->ParseFlags & ACPI_PARSE_TREE_MASK) != ACPI_PARSE_DELETE_TREE) ||
         (WalkState->OpInfo->Class == AML_CLASS_ARGUMENT))
    {
        return_ACPI_STATUS (AE_OK);
    }

    /* Make sure that we only delete this subtree */

    if (Op->Common.Parent)
    {
        Prev = Op->Common.Parent->Common.Value.Arg;
        if (!Prev)
        {
            /* Nothing more to do */

            goto Cleanup;
        }

        /*
         * Check if we need to replace the operator and its subtree
         * with a return value op (placeholder op)
         */
        ParentInfo = AcpiPsGetOpcodeInfo (Op->Common.Parent->Common.AmlOpcode);

        switch (ParentInfo->Class)
        {
        case AML_CLASS_CONTROL:
            break;

        case AML_CLASS_CREATE:

            /*
             * These opcodes contain TermArg operands.  The current
             * op must be replaced by a placeholder return op
             */
            ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
            if (!ReplacementOp)
            {
                goto AllocateError;
            }
            break;

        case AML_CLASS_NAMED_OBJECT:

            /*
             * These opcodes contain TermArg operands.  The current
             * op must be replaced by a placeholder return op
             */
            if ((Op->Common.Parent->Common.AmlOpcode == AML_REGION_OP)       ||
                (Op->Common.Parent->Common.AmlOpcode == AML_DATA_REGION_OP)  ||
                (Op->Common.Parent->Common.AmlOpcode == AML_BUFFER_OP)       ||
                (Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP)      ||
                (Op->Common.Parent->Common.AmlOpcode == AML_BANK_FIELD_OP)   ||
                (Op->Common.Parent->Common.AmlOpcode == AML_VAR_PACKAGE_OP))
            {
                ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
                if (!ReplacementOp)
                {
                    goto AllocateError;
                }
            }
            else if ((Op->Common.Parent->Common.AmlOpcode == AML_NAME_OP) &&
                     (WalkState->PassNumber <= ACPI_IMODE_LOAD_PASS2))
            {
                if ((Op->Common.AmlOpcode == AML_BUFFER_OP) ||
                    (Op->Common.AmlOpcode == AML_PACKAGE_OP) ||
                    (Op->Common.AmlOpcode == AML_VAR_PACKAGE_OP))
                {
                    ReplacementOp = AcpiPsAllocOp (Op->Common.AmlOpcode);
                    if (!ReplacementOp)
                    {
                        goto AllocateError;
                    }

                    ReplacementOp->Named.Data = Op->Named.Data;
                    ReplacementOp->Named.Length = Op->Named.Length;
                }
            }
            break;

        default:

            ReplacementOp = AcpiPsAllocOp (AML_INT_RETURN_VALUE_OP);
            if (!ReplacementOp)
            {
                goto AllocateError;
            }
        }

        /* We must unlink this op from the parent tree */

        if (Prev == Op)
        {
            /* This op is the first in the list */

            if (ReplacementOp)
            {
                ReplacementOp->Common.Parent        = Op->Common.Parent;
                ReplacementOp->Common.Value.Arg     = NULL;
                ReplacementOp->Common.Node          = Op->Common.Node;
                Op->Common.Parent->Common.Value.Arg = ReplacementOp;
                ReplacementOp->Common.Next          = Op->Common.Next;
            }
            else
            {
                Op->Common.Parent->Common.Value.Arg = Op->Common.Next;
            }
        }

        /* Search the parent list */

        else while (Prev)
        {
            /* Traverse all siblings in the parent's argument list */

            Next = Prev->Common.Next;
            if (Next == Op)
            {
                if (ReplacementOp)
                {
                    ReplacementOp->Common.Parent    = Op->Common.Parent;
                    ReplacementOp->Common.Value.Arg = NULL;
                    ReplacementOp->Common.Node      = Op->Common.Node;
                    Prev->Common.Next               = ReplacementOp;
                    ReplacementOp->Common.Next      = Op->Common.Next;
                    Next = NULL;
                }
                else
                {
                    Prev->Common.Next = Op->Common.Next;
                    Next = NULL;
                }
            }
            Prev = Next;
        }
    }


Cleanup:

    /* Now we can actually delete the subtree rooted at Op */

    AcpiPsDeleteParseTree (Op);
    return_ACPI_STATUS (AE_OK);


AllocateError:

    /* Always delete the subtree, even on error */

    AcpiPsDeleteParseTree (Op);
    return_ACPI_STATUS (AE_NO_MEMORY);
}


/*******************************************************************************