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

 *

 * Module Name: psloop - Main AML parse loop

 *

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

/*

 * Copyright (C) 2000 - 2018, Intel Corp.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions, and the following disclaimer,

 *    without modification.

 * 2. Redistributions in binary form must reproduce at minimum a disclaimer

 *    substantially similar to the "NO WARRANTY" disclaimer below

 *    ("Disclaimer") and any redistribution must be conditioned upon

 *    including a substantially similar Disclaimer requirement for further

 *    binary redistribution.

 * 3. Neither the names of the above-listed copyright holders nor the names

 *    of any contributors may be used to endorse or promote products derived

 *    from this software without specific prior written permission.

 *

 * Alternatively, this software may be distributed under the terms of the

 * GNU General Public License ("GPL") version 2 as published by the Free

 * Software Foundation.

 *

 * NO WARRANTY

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGES.

 */

/*

 * Parse the AML and build an operation tree as most interpreters, (such as

 * Perl) do. Parsing is done by hand rather than with a YACC generated parser

 * to tightly constrain stack and dynamic memory usage. 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 "accommon.h"

#include "acinterp.h"

#include "acparser.h"

#include "acdispat.h"

#include "amlcode.h"

#include "acconvert.h"

#define _COMPONENT          ACPI_PARSER

        ACPI_MODULE_NAME    ("psloop")

/* Local prototypes */

static ACPI_STATUS

AcpiPsGetArguments (

    ACPI_WALK_STATE         *WalkState,

    UINT8                   *AmlOpStart,

    ACPI_PARSE_OBJECT       *Op);

static void

AcpiPsLinkModuleCode (

    ACPI_PARSE_OBJECT       *ParentOp,

    UINT8                   *AmlStart,

    UINT32                  AmlLength,

    ACPI_OWNER_ID           OwnerId);

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

 *

 * FUNCTION:    AcpiPsGetArguments

 *

 * PARAMETERS:  WalkState           - Current state

 *              AmlOpStart          - Op start in AML

 *              Op                  - Current Op

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Get arguments for passed Op.

 *

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

static ACPI_STATUS

AcpiPsGetArguments (

    ACPI_WALK_STATE         *WalkState,

    UINT8                   *AmlOpStart,

    ACPI_PARSE_OBJECT       *Op)

{

    ACPI_STATUS             Status = AE_OK;

    ACPI_PARSE_OBJECT       *Arg = NULL;

    const ACPI_OPCODE_INFO  *OpInfo;

    ACPI_FUNCTION_TRACE_PTR (PsGetArguments, WalkState);

    ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

        "Get arguments for opcode [%s]\n", Op->Common.AmlOpName));

    switch (Op->Common.AmlOpcode)

    {

    case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */

    case AML_WORD_OP:       /* AML_WORDDATA_ARG */

    case AML_DWORD_OP:      /* AML_DWORDATA_ARG */

    case AML_QWORD_OP:      /* AML_QWORDATA_ARG */

    case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */

        /* Fill in constant or string argument directly */

        AcpiPsGetNextSimpleArg (&(WalkState->ParserState),

            GET_CURRENT_ARG_TYPE (WalkState->ArgTypes), Op);

        break;

    case AML_INT_NAMEPATH_OP:   /* AML_NAMESTRING_ARG */

        Status = AcpiPsGetNextNamepath (WalkState,

            &(WalkState->ParserState), Op, ACPI_POSSIBLE_METHOD_CALL);

        if (ACPI_FAILURE (Status))

        {

            return_ACPI_STATUS (Status);

        }

        WalkState->ArgTypes = 0;

        break;

    default:

        /*

         * Op is not a constant or string, append each argument to the Op

         */

        while (GET_CURRENT_ARG_TYPE (WalkState->ArgTypes) &&

            !WalkState->ArgCount)

        {

            WalkState->Aml = WalkState->ParserState.Aml;

            switch (Op->Common.AmlOpcode)

            {

            case AML_METHOD_OP:

            case AML_BUFFER_OP:

            case AML_PACKAGE_OP:

            case AML_VARIABLE_PACKAGE_OP:

            case AML_WHILE_OP:

                break;

            default:

                ASL_CV_CAPTURE_COMMENTS (WalkState);

                break;

            }

            Status = AcpiPsGetNextArg (WalkState, &(WalkState->ParserState),

                GET_CURRENT_ARG_TYPE (WalkState->ArgTypes), &Arg;;

            if (ACPI_FAILURE (Status))

            {

                return_ACPI_STATUS (Status);

            }

            if (Arg)

            {

                AcpiPsAppendArg (Op, Arg);

            }

            INCREMENT_ARG_LIST (WalkState->ArgTypes);

        }

        ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

            "Final argument count: %8.8X pass %u\n",

            WalkState->ArgCount, WalkState->PassNumber));

        /*

         * This case handles the legacy option that groups all module-level

         * code blocks together and defers execution until all of the tables

         * are loaded. Execute all of these blocks at this time.

         * Execute any module-level code that was detected during the table

         * load phase.

         *

         * Note: this option is deprecated and will be eliminated in the

         * future. Use of this option can cause problems with AML code that

         * depends upon in-order immediate execution of module-level code.

         */

        if (AcpiGbl_GroupModuleLevelCode &&

            (WalkState->PassNumber <= ACPI_IMODE_LOAD_PASS2) &&

            ((WalkState->ParseFlags & ACPI_PARSE_DISASSEMBLE) == 0))

        {

            /*

             * We want to skip If/Else/While constructs during Pass1 because we

             * want to actually conditionally execute the code during Pass2.

             *

             * Except for disassembly, where we always want to walk the

             * If/Else/While packages

             */

            switch (Op->Common.AmlOpcode)

            {

            case AML_IF_OP:

            case AML_ELSE_OP:

            case AML_WHILE_OP:

                /*

                 * Currently supported module-level opcodes are:

                 * IF/ELSE/WHILE. These appear to be the most common,

                 * and easiest to support since they open an AML

                 * package.

                 */

                if (WalkState->PassNumber == ACPI_IMODE_LOAD_PASS1)

                {

                    AcpiPsLinkModuleCode (Op->Common.Parent, AmlOpStart,

                        (UINT32) (WalkState->ParserState.PkgEnd - AmlOpStart),

                        WalkState->OwnerId);

                }

                ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

                    "Pass1: Skipping an If/Else/While body\n"));

                /* Skip body of if/else/while in pass 1 */

                WalkState->ParserState.Aml = WalkState->ParserState.PkgEnd;

                WalkState->ArgCount = 0;

                break;

            default:

                /*

                 * Check for an unsupported executable opcode at module

                 * level. We must be in PASS1, the parent must be a SCOPE,

                 * The opcode class must be EXECUTE, and the opcode must

                 * not be an argument to another opcode.

                 */

                if ((WalkState->PassNumber == ACPI_IMODE_LOAD_PASS1) &&

                    (Op->Common.Parent->Common.AmlOpcode == AML_SCOPE_OP))

                {

                    OpInfo = AcpiPsGetOpcodeInfo (Op->Common.AmlOpcode);

                    if ((OpInfo->Class == AML_CLASS_EXECUTE) &&

                        (!Arg))

                    {

                        ACPI_WARNING ((AE_INFO,

                            "Unsupported module-level executable opcode "

                            "0x%.2X at table offset 0x%.4X",

                            Op->Common.AmlOpcode,

                            (UINT32) (ACPI_PTR_DIFF (AmlOpStart,

                                WalkState->ParserState.AmlStart) +

                                sizeof (ACPI_TABLE_HEADER))));

                    }

                }

                break;

            }

        }

        /* Special processing for certain opcodes */

        switch (Op->Common.AmlOpcode)

        {

        case AML_METHOD_OP:

            /*

             * Skip parsing of control method because we don't have enough

             * info in the first pass to parse it correctly.

             *

             * Save the length and address of the body

             */

            Op->Named.Data = WalkState->ParserState.Aml;

            Op->Named.Length = (UINT32)

                (WalkState->ParserState.PkgEnd - WalkState->ParserState.Aml);

            /* Skip body of method */

            WalkState->ParserState.Aml = WalkState->ParserState.PkgEnd;

            WalkState->ArgCount = 0;

            break;

        case AML_BUFFER_OP:

        case AML_PACKAGE_OP:

        case AML_VARIABLE_PACKAGE_OP:

            if ((Op->Common.Parent) &&

                (Op->Common.Parent->Common.AmlOpcode == AML_NAME_OP) &&

                (WalkState->PassNumber <= ACPI_IMODE_LOAD_PASS2))

            {

                ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

                    "Setup Package/Buffer: Pass %u, AML Ptr: %p\n",

                    WalkState->PassNumber, AmlOpStart));

                /*

                 * Skip parsing of Buffers and Packages because we don't have

                 * enough info in the first pass to parse them correctly.

                 */

                Op->Named.Data = AmlOpStart;

                Op->Named.Length = (UINT32)

                    (WalkState->ParserState.PkgEnd - AmlOpStart);

                /* Skip body */

                WalkState->ParserState.Aml = WalkState->ParserState.PkgEnd;

                WalkState->ArgCount = 0;

            }

            break;

        case AML_WHILE_OP:

            if (WalkState->ControlState)

            {

                WalkState->ControlState->Control.PackageEnd =

                    WalkState->ParserState.PkgEnd;

            }

            break;

        default:

            /* No action for all other opcodes */

            break;

        }

        break;

    }

    return_ACPI_STATUS (AE_OK);

}

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

 *

 * FUNCTION:    AcpiPsLinkModuleCode

 *

 * PARAMETERS:  ParentOp            - Parent parser op

 *              AmlStart            - Pointer to the AML

 *              AmlLength           - Length of executable AML

 *              OwnerId             - OwnerId of module level code

 *

 * RETURN:      None.

 *

 * DESCRIPTION: Wrap the module-level code with a method object and link the

 *              object to the global list. Note, the mutex field of the method

 *              object is used to link multiple module-level code objects.

 *

 * NOTE: In this legacy option, each block of detected executable AML

 * code that is outside of any control method is wrapped with a temporary

 * control method object and placed on a global list below.

 *

 * This function executes the module-level code for all tables only after

 * all of the tables have been loaded. It is a legacy option and is

 * not compatible with other ACPI implementations. See AcpiNsLoadTable.

 *

 * This function will be removed when the legacy option is removed.

 *

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

static void

AcpiPsLinkModuleCode (

    ACPI_PARSE_OBJECT       *ParentOp,

    UINT8                   *AmlStart,

    UINT32                  AmlLength,

    ACPI_OWNER_ID           OwnerId)

{

    ACPI_OPERAND_OBJECT     *Prev;

    ACPI_OPERAND_OBJECT     *Next;

    ACPI_OPERAND_OBJECT     *MethodObj;

    ACPI_NAMESPACE_NODE     *ParentNode;

    ACPI_FUNCTION_TRACE (PsLinkModuleCode);

    /* Get the tail of the list */

    Prev = Next = AcpiGbl_ModuleCodeList;

    while (Next)

    {

        Prev = Next;

        Next = Next->Method.Mutex;

    }

    /*

     * Insert the module level code into the list. Merge it if it is

     * adjacent to the previous element.

     */

    if (!Prev ||

       ((Prev->Method.AmlStart + Prev->Method.AmlLength) != AmlStart))

    {

        /* Create, initialize, and link a new temporary method object */

        MethodObj = AcpiUtCreateInternalObject (ACPI_TYPE_METHOD);

        if (!MethodObj)

        {

            return_VOID;

        }

        ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

            "Create/Link new code block: %p\n", MethodObj));

        if (ParentOp->Common.Node)

        {

            ParentNode = ParentOp->Common.Node;

        }

        else

        {

            ParentNode = AcpiGbl_RootNode;

        }

        MethodObj->Method.AmlStart = AmlStart;

        MethodObj->Method.AmlLength = AmlLength;

        MethodObj->Method.OwnerId = OwnerId;

        MethodObj->Method.InfoFlags |= ACPI_METHOD_MODULE_LEVEL;

        /*

         * Save the parent node in NextObject. This is cheating, but we

         * don't want to expand the method object.

         */

        MethodObj->Method.NextObject =

            ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, ParentNode);

        if (!Prev)

        {

            AcpiGbl_ModuleCodeList = MethodObj;

        }

        else

        {

            Prev->Method.Mutex = MethodObj;

        }

    }

    else

    {

        ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

            "Appending to existing code block: %p\n", Prev));

        Prev->Method.AmlLength += AmlLength;

    }

    return_VOID;

}

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

 *

 * FUNCTION:    AcpiPsParseLoop

 *

 * PARAMETERS:  WalkState           - Current state

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return

 *              a tree of ops.

 *

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

ACPI_STATUS

AcpiPsParseLoop (

    ACPI_WALK_STATE         *WalkState)

{

    ACPI_STATUS             Status = AE_OK;

    ACPI_PARSE_OBJECT       *Op = NULL;     /* current op */

    ACPI_PARSE_STATE        *ParserState;

    UINT8                   *AmlOpStart = NULL;

    ACPI_FUNCTION_TRACE_PTR (PsParseLoop, WalkState);

    if (WalkState->DescendingCallback == NULL)

    {

        return_ACPI_STATUS (AE_BAD_PARAMETER);

    }

    ParserState = &WalkState->ParserState;

    WalkState->ArgTypes = 0;

#if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))

    if (WalkState->WalkType & ACPI_WALK_METHOD_RESTART)

    {

        /* We are restarting a preempted control method */

        if (AcpiPsHasCompletedScope (ParserState))

        {

            /*

             * We must check if a predicate to an IF or WHILE statement

             * was just completed

             */

            if ((ParserState->Scope->ParseScope.Op) &&

               ((ParserState->Scope->ParseScope.Op->Common.AmlOpcode == AML_IF_OP) ||

                (ParserState->Scope->ParseScope.Op->Common.AmlOpcode == AML_WHILE_OP)) &&

                (WalkState->ControlState) &&

                (WalkState->ControlState->Common.State ==

                    ACPI_CONTROL_PREDICATE_EXECUTING))

            {

                /*

                 * A predicate was just completed, get the value of the

                 * predicate and branch based on that value

                 */

                WalkState->Op = NULL;

                Status = AcpiDsGetPredicateValue (WalkState, ACPI_TO_POINTER (TRUE));

                if (ACPI_FAILURE (Status) &&

                    ((Status & AE_CODE_MASK) != AE_CODE_CONTROL))

                {

                    if (Status == AE_AML_NO_RETURN_VALUE)

                    {

                        ACPI_EXCEPTION ((AE_INFO, Status,

                            "Invoked method did not return a value"));

                    }

                    ACPI_EXCEPTION ((AE_INFO, Status, "GetPredicate Failed"));

                    return_ACPI_STATUS (Status);

                }

                Status = AcpiPsNextParseState (WalkState, Op, Status);

            }

            AcpiPsPopScope (ParserState, &Op,

                &WalkState->ArgTypes, &WalkState->ArgCount);

            ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", Op));

        }

        else if (WalkState->PrevOp)

        {

            /* We were in the middle of an op */

            Op = WalkState->PrevOp;

            WalkState->ArgTypes = WalkState->PrevArgTypes;

        }

    }

#endif

    /* Iterative parsing loop, while there is more AML to process: */

    while ((ParserState->Aml < ParserState->AmlEnd) || (Op))

    {

        ASL_CV_CAPTURE_COMMENTS (WalkState);

        AmlOpStart = ParserState->Aml;

        if (!Op)

        {

            Status = AcpiPsCreateOp (WalkState, AmlOpStart, &Op);

            if (ACPI_FAILURE (Status))

            {

                if (Status == AE_CTRL_PARSE_CONTINUE)

                {

                    continue;

                }

                if (Status == AE_CTRL_PARSE_PENDING)

                {

                    Status = AE_OK;

                }

                if (Status == AE_CTRL_TERMINATE)

                {

                    return_ACPI_STATUS (Status);

                }

                Status = AcpiPsCompleteOp (WalkState, &Op, Status);

                if (ACPI_FAILURE (Status))

                {

                    return_ACPI_STATUS (Status);

                }

                if (WalkState->Opcode == AML_SCOPE_OP)

                {

                    /*

                     * If the scope op fails to parse, skip the body of the

                     * scope op because the parse failure indicates that the

                     * device may not exist.

                     */

                    WalkState->ParserState.Aml = WalkState->Aml + 1;

                    WalkState->ParserState.Aml =

                        AcpiPsGetNextPackageEnd(&WalkState->ParserState);

                    WalkState->Aml = WalkState->ParserState.Aml;

                    ACPI_ERROR ((AE_INFO, "Skipping Scope block"));

                }

                continue;

            }

            AcpiExStartTraceOpcode (Op, WalkState);

        }

        /*

         * Start ArgCount at zero because we don't know if there are

         * any args yet

         */

        WalkState->ArgCount = 0;

        switch (Op->Common.AmlOpcode)

        {

        case AML_BYTE_OP:

        case AML_WORD_OP:

        case AML_DWORD_OP:

        case AML_QWORD_OP:

            break;

        default:

            ASL_CV_CAPTURE_COMMENTS (WalkState);

            break;

        }

        /* Are there any arguments that must be processed? */

        if (WalkState->ArgTypes)

        {

            /* Get arguments */

            Status = AcpiPsGetArguments (WalkState, AmlOpStart, Op);

            if (ACPI_FAILURE (Status))

            {

                Status = AcpiPsCompleteOp (WalkState, &Op, Status);

                if (ACPI_FAILURE (Status))

                {

                    return_ACPI_STATUS (Status);

                }

                if ((WalkState->ControlState) &&

                    ((WalkState->ControlState->Control.Opcode == AML_IF_OP) ||

                    (WalkState->ControlState->Control.Opcode == AML_WHILE_OP)))

                {

                    /*

                     * If the if/while op fails to parse, we will skip parsing

                     * the body of the op.

                     */

                    ParserState->Aml =

                        WalkState->ControlState->Control.AmlPredicateStart + 1;

                    ParserState->Aml =

                        AcpiPsGetNextPackageEnd (ParserState);

                    WalkState->Aml = ParserState->Aml;

                    ACPI_ERROR ((AE_INFO, "Skipping While/If block"));

                    if (*WalkState->Aml == AML_ELSE_OP)

                    {

                        ACPI_ERROR ((AE_INFO, "Skipping Else block"));

                        WalkState->ParserState.Aml = WalkState->Aml + 1;

                        WalkState->ParserState.Aml =

                            AcpiPsGetNextPackageEnd (ParserState);

                        WalkState->Aml = ParserState->Aml;

                    }

                    ACPI_FREE(AcpiUtPopGenericState (&WalkState->ControlState));

                }

                Op = NULL;

                continue;

            }

        }

        /* Check for arguments that need to be processed */

        ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,

            "Parseloop: argument count: %8.8X\n", WalkState->ArgCount));

        if (WalkState->ArgCount)

        {

            /*

             * There are arguments (complex ones), push Op and

             * prepare for argument

             */

            Status = AcpiPsPushScope (ParserState, Op,

                WalkState->ArgTypes, WalkState->ArgCount);

            if (ACPI_FAILURE (Status))

            {

                Status = AcpiPsCompleteOp (WalkState, &Op, Status);

                if (ACPI_FAILURE (Status))

                {

                    return_ACPI_STATUS (Status);

                }

                continue;

            }

            Op = NULL;

            continue;

        }

        /*

         * All arguments have been processed -- Op is complete,

         * prepare for next

         */

        WalkState->OpInfo = AcpiPsGetOpcodeInfo (Op->Common.AmlOpcode);

        if (WalkState->OpInfo->Flags & AML_NAMED)

        {

            if (Op->Common.AmlOpcode == AML_REGION_OP ||

                Op->Common.AmlOpcode == AML_DATA_REGION_OP)

            {

                /*

                 * Skip parsing of control method or opregion body,

                 * because we don't have enough info in the first pass

                 * to parse them correctly.

                 *

                 * Completed parsing an OpRegion declaration, we now

                 * know the length.

                 */

                Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data);

            }

        }

        if (WalkState->OpInfo->Flags & AML_CREATE)

        {

            /*

             * Backup to beginning of CreateXXXfield declaration (1 for

             * Opcode)

             *

             * BodyLength is unknown until we parse the body

             */

            Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data);

        }

        if (Op->Common.AmlOpcode == AML_BANK_FIELD_OP)

        {

            /*

             * Backup to beginning of BankField declaration

             *

             * BodyLength is unknown until we parse the body

             */

            Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data);

        }

        /* This op complete, notify the dispatcher */

        if (WalkState->AscendingCallback != NULL)

        {

            WalkState->Op = Op;

            WalkState->Opcode = Op->Common.AmlOpcode;

            Status = WalkState->AscendingCallback (WalkState);

            Status = AcpiPsNextParseState (WalkState, Op, Status);

            if (Status == AE_CTRL_PENDING)

            {

                Status = AE_OK;

            }

        }

        Status = AcpiPsCompleteOp (WalkState, &Op, Status);

        if (ACPI_FAILURE (Status))

        {

            return_ACPI_STATUS (Status);

        }

    } /* while ParserState->Aml */

    Status = AcpiPsCompleteFinalOp (WalkState, Op, Status);

    return_ACPI_STATUS (Status);

}