text: /******************************************************************************
   *
   * Module Name: aslanalyze.c - Support functions for parse tree walks
   *
   *****************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2016, 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.
   */
  
  #include "aslcompiler.h"
  #include "aslcompiler.y.h"
  #include <string.h>
  
  
  #define _COMPONENT          ACPI_COMPILER
          ACPI_MODULE_NAME    ("aslanalyze")
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnIsInternalMethod
   *
   * PARAMETERS:  Op                  - Current op
   *
   * RETURN:      Boolean
   *
   * DESCRIPTION: Check for an internal control method.
   *
   ******************************************************************************/
  
  BOOLEAN
  AnIsInternalMethod (
      ACPI_PARSE_OBJECT       *Op)
  {
  
      if ((!strcmp (Op->Asl.ExternalName, "\\_OSI")) ||
          (!strcmp (Op->Asl.ExternalName, "_OSI")))
      {
          return (TRUE);
      }
  
      return (FALSE);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnGetInternalMethodReturnType
   *
   * PARAMETERS:  Op                  - Current op
   *
   * RETURN:      Btype
   *
   * DESCRIPTION: Get the return type of an internal method
   *
   ******************************************************************************/
  
  UINT32
  AnGetInternalMethodReturnType (
      ACPI_PARSE_OBJECT       *Op)
  {
  
      if ((!strcmp (Op->Asl.ExternalName, "\\_OSI")) ||
          (!strcmp (Op->Asl.ExternalName, "_OSI")))
      {
          return (ACPI_BTYPE_STRING);
      }
  
      return (0);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnCheckId
   *
   * PARAMETERS:  Op                  - Current parse op
   *              Type                - HID or CID
   *
   * RETURN:      None
   *
   * DESCRIPTION: Perform various checks on _HID and _CID strings. Only limited
   *              checks can be performed on _CID strings.
   *
   ******************************************************************************/
  
  void
  AnCheckId (
      ACPI_PARSE_OBJECT       *Op,
      ACPI_NAME               Type)
  {
      UINT32                  i;
      ACPI_SIZE               Length;
  
  
      /* Only care about string versions of _HID/_CID (integers are legal) */
  
      if (Op->Asl.ParseOpcode != PARSEOP_STRING_LITERAL)
      {
          return;
      }
  
      /* For both _HID and _CID, the string must be non-null */
  
      Length = strlen (Op->Asl.Value.String);
      if (!Length)
      {
          AslError (ASL_ERROR, ASL_MSG_NULL_STRING, Op, NULL);
          return;
      }
  
      /*
       * One of the things we want to catch here is the use of a leading
       * asterisk in the string -- an odd construct that certain platform
       * manufacturers are fond of. Technically, a leading asterisk is OK
       * for _CID, but a valid use of this has not been seen.
       */
      if (*Op->Asl.Value.String == '*')
      {
          AslError (ASL_ERROR, ASL_MSG_LEADING_ASTERISK,
              Op, Op->Asl.Value.String);
          return;
      }
  
      /* _CID strings are bus-specific, no more checks can be performed */
  
      if (Type == ASL_TYPE_CID)
      {
          return;
      }
  
      /* For _HID, all characters must be alphanumeric */
  
      for (i = 0; Op->Asl.Value.String[i]; i++)
      {
          if (!isalnum ((int) Op->Asl.Value.String[i]))
          {
              AslError (ASL_ERROR, ASL_MSG_ALPHANUMERIC_STRING,
                  Op, Op->Asl.Value.String);
              return;
          }
      }
  
      /*
       * _HID String must be one of these forms:
       *
       * "AAA####"    A is an uppercase letter and # is a hex digit
       * "ACPI####"   # is a hex digit
       * "NNNN####"   N is an uppercase letter or decimal digit (0-9)
       *              # is a hex digit (ACPI 5.0)
       */
      if ((Length < 7) || (Length > 8))
      {
          AslError (ASL_ERROR, ASL_MSG_HID_LENGTH,
              Op, Op->Asl.Value.String);
          return;
      }
  
      /* _HID Length is valid (7 or 8), now check prefix (first 3 or 4 chars) */
  
      if (Length == 7)
      {
          /* AAA####: Ensure the alphabetic prefix is all uppercase */
  
          for (i = 0; i < 3; i++)
          {
              if (!isupper ((int) Op->Asl.Value.String[i]))
              {
                  AslError (ASL_ERROR, ASL_MSG_UPPER_CASE,
                      Op, &Op->Asl.Value.String[i]);
                  return;
              }
          }
      }
      else /* Length == 8 */
      {
          /*
           * ACPI#### or NNNN####:
           * Ensure the prefix contains only uppercase alpha or decimal digits
           */
          for (i = 0; i < 4; i++)
          {
              if (!isupper ((int) Op->Asl.Value.String[i]) &&
                  !isdigit ((int) Op->Asl.Value.String[i]))
              {
                  AslError (ASL_ERROR, ASL_MSG_HID_PREFIX,
                      Op, &Op->Asl.Value.String[i]);
                  return;
              }
          }
      }
  
      /* Remaining characters (suffix) must be hex digits */
  
      for (; i < Length; i++)
      {
          if (!isxdigit ((int) Op->Asl.Value.String[i]))
          {
              AslError (ASL_ERROR, ASL_MSG_HID_SUFFIX,
                  Op, &Op->Asl.Value.String[i]);
              break;
          }
      }
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnLastStatementIsReturn
   *
   * PARAMETERS:  Op                  - A method parse node
   *
   * RETURN:      TRUE if last statement is an ASL RETURN. False otherwise
   *
   * DESCRIPTION: Walk down the list of top level statements within a method
   *              to find the last one. Check if that last statement is in
   *              fact a RETURN statement.
   *
   ******************************************************************************/
  
  BOOLEAN
  AnLastStatementIsReturn (
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *Next;
  
  
      /* Check if last statement is a return */
  
      Next = ASL_GET_CHILD_NODE (Op);
      while (Next)
      {
          if ((!Next->Asl.Next) &&
              (Next->Asl.ParseOpcode == PARSEOP_RETURN))
          {
              return (TRUE);
          }
  
          Next = ASL_GET_PEER_NODE (Next);
      }
  
      return (FALSE);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnCheckMethodReturnValue
   *
   * PARAMETERS:  Op                  - Parent
   *              OpInfo              - Parent info
   *              ArgOp               - Method invocation op
   *              RequiredBtypes      - What caller requires
   *              ThisNodeBtype       - What this node returns (if anything)
   *
   * RETURN:      None
   *
   * DESCRIPTION: Check a method invocation for 1) A return value and if it does
   *              in fact return a value, 2) check the type of the return value.
   *
   ******************************************************************************/
  
  void
  AnCheckMethodReturnValue (
      ACPI_PARSE_OBJECT       *Op,
      const ACPI_OPCODE_INFO  *OpInfo,
      ACPI_PARSE_OBJECT       *ArgOp,
      UINT32                  RequiredBtypes,
      UINT32                  ThisNodeBtype)
  {
      ACPI_PARSE_OBJECT       *OwningOp;
      ACPI_NAMESPACE_NODE     *Node;
  
  
      Node = ArgOp->Asl.Node;
  
      if (!Node)
      {
          /* No error message, this can happen and is OK */
  
          return;
      }
  
      /* Examine the parent op of this method */
  
      OwningOp = Node->Op;
      if (OwningOp->Asl.CompileFlags & NODE_METHOD_NO_RETVAL)
      {
          /* Method NEVER returns a value */
  
          AslError (ASL_ERROR, ASL_MSG_NO_RETVAL, Op, Op->Asl.ExternalName);
      }
      else if (OwningOp->Asl.CompileFlags & NODE_METHOD_SOME_NO_RETVAL)
      {
          /* Method SOMETIMES returns a value, SOMETIMES not */
  
          AslError (ASL_WARNING, ASL_MSG_SOME_NO_RETVAL,
              Op, Op->Asl.ExternalName);
      }
      else if (!(ThisNodeBtype & RequiredBtypes))
      {
          /* Method returns a value, but the type is wrong */
  
          AnFormatBtype (StringBuffer, ThisNodeBtype);
          AnFormatBtype (StringBuffer2, RequiredBtypes);
  
          /*
           * The case where the method does not return any value at all
           * was already handled in the namespace cross reference
           * -- Only issue an error if the method in fact returns a value,
           * but it is of the wrong type
           */
          if (ThisNodeBtype != 0)
          {
              sprintf (MsgBuffer,
                  "Method returns [%s], %s operator requires [%s]",
                  StringBuffer, OpInfo->Name, StringBuffer2);
  
              AslError (ASL_ERROR, ASL_MSG_INVALID_TYPE, ArgOp, MsgBuffer);
          }
      }
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AnIsResultUsed
   *
   * PARAMETERS:  Op                  - Parent op for the operator
   *
   * RETURN:      TRUE if result from this operation is actually consumed
   *
   * DESCRIPTION: Determine if the function result value from an operator is
   *              used.
   *
   ******************************************************************************/
  
  BOOLEAN
  AnIsResultUsed (
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *Parent;
  
  
      switch (Op->Asl.ParseOpcode)
      {
      case PARSEOP_INCREMENT:
      case PARSEOP_DECREMENT:
  
          /* These are standalone operators, no return value */
  
          return (TRUE);
  
      default:
  
          break;
      }
  
      /* Examine parent to determine if the return value is used */
  
      Parent = Op->Asl.Parent;
      switch (Parent->Asl.ParseOpcode)
      {
      /* If/While - check if the operator is the predicate */
  
      case PARSEOP_IF:
      case PARSEOP_WHILE:
  
          /* First child is the predicate */
  
          if (Parent->Asl.Child == Op)
          {
              return (TRUE);
          }
  
          return (FALSE);
  
      /* Not used if one of these is the parent */
  
      case PARSEOP_METHOD:
      case PARSEOP_DEFINITION_BLOCK:
      case PARSEOP_ELSE:
  
          return (FALSE);
  
      default:
  
          /* Any other type of parent means that the result is used */
  
          return (TRUE);
      }
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    ApCheckForGpeNameConflict
   *
   * PARAMETERS:  Op                  - Current parse op
   *
   * RETURN:      None
   *
   * DESCRIPTION: Check for a conflict between GPE names within this scope.
   *              Conflict means two GPE names with the same GPE number, but
   *              different types -- such as _L1C and _E1C.
   *
   ******************************************************************************/
  
  void
  ApCheckForGpeNameConflict (
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *NextOp;
      UINT32                  GpeNumber;
      char                    Name[ACPI_NAME_SIZE + 1];
      char                    Target[ACPI_NAME_SIZE];
  
  
      /* Need a null-terminated string version of NameSeg */
  
      ACPI_MOVE_32_TO_32 (Name, &Op->Asl.NameSeg);
      Name[ACPI_NAME_SIZE] = 0;
  
      /*
       * For a GPE method:
       * 1st char must be underscore
       * 2nd char must be L or E
       * 3rd/4th chars must be a hex number
       */
      if ((Name[0] != '_') ||
         ((Name[1] != 'L') && (Name[1] != 'E')))
      {
          return;
      }
  
      /* Verify 3rd/4th chars are a valid hex value */
  
      GpeNumber = strtoul (&Name[2], NULL, 16);
      if (GpeNumber == ACPI_UINT32_MAX)
      {
          return;
      }
  
      /*
       * We are now sure we have an _Lxx or _Exx.
       * Create the target name that would cause collision (Flip E/L)
       */
      ACPI_MOVE_32_TO_32 (Target, Name);
  
      /* Inject opposite letter ("L" versus "E") */
  
      if (Name[1] == 'L')
      {
          Target[1] = 'E';
      }
      else /* Name[1] == 'E' */
      {
          Target[1] = 'L';
      }
  
      /* Search all peers (objects within this scope) for target match */
  
      NextOp = Op->Asl.Next;
      while (NextOp)
      {
          /*
           * We mostly care about methods, but check Name() constructs also,
           * even though they will get another error for not being a method.
           * All GPE names must be defined as control methods.
           */
          if ((NextOp->Asl.ParseOpcode == PARSEOP_METHOD) ||
              (NextOp->Asl.ParseOpcode == PARSEOP_NAME))
          {
              if (ACPI_COMPARE_NAME (Target, NextOp->Asl.NameSeg))
              {
                  /* Found both _Exy and _Lxy in the same scope, error */
  
                  AslError (ASL_ERROR, ASL_MSG_GPE_NAME_CONFLICT, NextOp,
                      Name);
                  return;
              }
          }
  
          NextOp = NextOp->Asl.Next;
      }
  
      /* OK, no conflict found */
  
      return;
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    ApCheckRegMethod
   *
   * PARAMETERS:  Op                  - Current parse op
   *
   * RETURN:      None
   *
   * DESCRIPTION: Ensure that a _REG method has a corresponding Operation
   *              Region declaration within the same scope. Note: _REG is defined
   *              to have two arguments and must therefore be defined as a
   *              control method.
   *
   ******************************************************************************/
  
  void
  ApCheckRegMethod (
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *Next;
      ACPI_PARSE_OBJECT       *Parent;
  
  
      /* We are only interested in _REG methods */
  
      if (!ACPI_COMPARE_NAME (METHOD_NAME__REG, &Op->Asl.NameSeg))
      {
          return;
      }
  
      /* Get the start of the current scope */
  
      Parent = Op->Asl.Parent;
      Next = Parent->Asl.Child;
  
      /* Search entire scope for an operation region declaration */
  
      while (Next)
      {
          if (Next->Asl.ParseOpcode == PARSEOP_OPERATIONREGION)
          {
              return; /* Found region, OK */
          }
  
          Next = Next->Asl.Next;
      }
  
      /* No region found, issue warning */
  
      AslError (ASL_WARNING, ASL_MSG_NO_REGION, Op, NULL);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    ApFindNameInScope
   *
   * PARAMETERS:  Name                - Name to search for
   *              Op                  - Current parse op
   *
   * RETURN:      TRUE if name found in the same scope as Op.
   *
   * DESCRIPTION: Determine if a name appears in the same scope as Op, as either
   *              a Method() or a Name().
   *
   ******************************************************************************/
  
  BOOLEAN
  ApFindNameInScope (
      char                    *Name,
      ACPI_PARSE_OBJECT       *Op)
  {
      ACPI_PARSE_OBJECT       *Next;
      ACPI_PARSE_OBJECT       *Parent;
  
  
      /* Get the start of the current scope */
  
      Parent = Op->Asl.Parent;
      Next = Parent->Asl.Child;
  
      /* Search entire scope for a match to the name */
  
      while (Next)
      {
          if ((Next->Asl.ParseOpcode == PARSEOP_METHOD) ||
              (Next->Asl.ParseOpcode == PARSEOP_NAME))
          {
              if (ACPI_COMPARE_NAME (Name, Next->Asl.NameSeg))
              {
                  return (TRUE);
              }
          }
  
          Next = Next->Asl.Next;
      }
  
      return (FALSE);
  }
  