nsutils.c

acpi tools for linux include acpiexec and acpixtract

 *
 * DESCRIPTION: Calculate the length of the internal (AML) namestring
 *              corresponding to the external (ASL) namestring.
 *
 ******************************************************************************/

void
AcpiNsGetInternalNameLength (
    ACPI_NAMESTRING_INFO    *Info)
{
    char                    *NextExternalChar;
    UINT32                  i;


    ACPI_FUNCTION_ENTRY ();


    NextExternalChar = Info->ExternalName;
    Info->NumCarats = 0;
    Info->NumSegments = 0;
    Info->FullyQualified = FALSE;

    /*
     * For the internal name, the required length is 4 bytes per segment, plus
     * 1 each for RootPrefix, MultiNamePrefixOp, segment count, trailing null
     * (which is not really needed, but no there's harm in putting it there)
     *
     * strlen() + 1 covers the first NameSeg, which has no path separator
     */
    if (AcpiNsValidRootPrefix (NextExternalChar[0]))
    {
        Info->FullyQualified = TRUE;
        NextExternalChar++;
    }
    else
    {
        /*
         * Handle Carat prefixes
         */
        while (*NextExternalChar == '^')
        {
            Info->NumCarats++;
            NextExternalChar++;
        }
    }

    /*
     * Determine the number of ACPI name "segments" by counting the number of
     * path separators within the string. Start with one segment since the
     * segment count is [(# separators) + 1], and zero separators is ok.
     */
    if (*NextExternalChar)
    {
        Info->NumSegments = 1;
        for (i = 0; NextExternalChar[i]; i++)
        {
            if (AcpiNsValidPathSeparator (NextExternalChar[i]))
            {
                Info->NumSegments++;
            }
        }
    }

    Info->Length = (ACPI_NAME_SIZE * Info->NumSegments) +
                    4 + Info->NumCarats;

    Info->NextExternalChar = NextExternalChar;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiNsBuildInternalName
 *
 * PARAMETERS:  Info            - Info struct fully initialized
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Construct the internal (AML) namestring
 *              corresponding to the external (ASL) namestring.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiNsBuildInternalName (
    ACPI_NAMESTRING_INFO    *Info)
{
    UINT32                  NumSegments = Info->NumSegments;
    char                    *InternalName = Info->InternalName;
    char                    *ExternalName = Info->NextExternalChar;
    char                    *Result = NULL;
    ACPI_NATIVE_UINT        i;


    ACPI_FUNCTION_TRACE (NsBuildInternalName);


    /* Setup the correct prefixes, counts, and pointers */

    if (Info->FullyQualified)
    {
        InternalName[0] = '\\';

        if (NumSegments <= 1)
        {
            Result = &InternalName[1];
        }
        else if (NumSegments == 2)
        {
            InternalName[1] = AML_DUAL_NAME_PREFIX;
            Result = &InternalName[2];
        }
        else
        {
            InternalName[1] = AML_MULTI_NAME_PREFIX_OP;
            InternalName[2] = (char) NumSegments;
            Result = &InternalName[3];
        }
    }
    else
    {
        /*
         * Not fully qualified.
         * Handle Carats first, then append the name segments
         */
        i = 0;
        if (Info->NumCarats)
        {
            for (i = 0; i < Info->NumCarats; i++)
            {
                InternalName[i] = '^';
            }
        }

        if (NumSegments <= 1)
        {
            Result = &InternalName[i];
        }
        else if (NumSegments == 2)
        {
            InternalName[i] = AML_DUAL_NAME_PREFIX;
            Result = &InternalName[(ACPI_NATIVE_UINT) (i+1)];
        }
        else
        {
            InternalName[i] = AML_MULTI_NAME_PREFIX_OP;
            InternalName[(ACPI_NATIVE_UINT) (i+1)] = (char) NumSegments;
            Result = &InternalName[(ACPI_NATIVE_UINT) (i+2)];
        }
    }

    /* Build the name (minus path separators) */

    for (; NumSegments; NumSegments--)
    {
        for (i = 0; i < ACPI_NAME_SIZE; i++)
        {
            if (AcpiNsValidPathSeparator (*ExternalName) ||
               (*ExternalName == 0))
            {
                /* Pad the segment with underscore(s) if segment is short */

                Result[i] = '_';
            }
            else
            {
                /* Convert the character to uppercase and save it */

                Result[i] = (char) ACPI_TOUPPER ((int) *ExternalName);
                ExternalName++;
            }
        }

        /* Now we must have a path separator, or the pathname is bad */

        if (!AcpiNsValidPathSeparator (*ExternalName) &&
            (*ExternalName != 0))
        {
            return_ACPI_STATUS (AE_BAD_PARAMETER);
        }

        /* Move on the next segment */

        ExternalName++;
        Result += ACPI_NAME_SIZE;
    }

    /* Terminate the string */

    *Result = 0;

    if (Info->FullyQualified)
    {
        ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Returning [%p] (abs) \"\\%s\"\n",
            InternalName, InternalName));
    }
    else
    {
        ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Returning [%p] (rel) \"%s\"\n",
            InternalName, InternalName));
    }

    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiNsInternalizeName
 *
 * PARAMETERS:  *ExternalName           - External representation of name
 *              **Converted Name        - Where to return the resulting
 *                                        internal represention of the name
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
 *              to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
 *
 *******************************************************************************/

ACPI_STATUS
AcpiNsInternalizeName (
    char                    *ExternalName,
    char                    **ConvertedName)
{
    char                    *InternalName;
    ACPI_NAMESTRING_INFO    Info;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (NsInternalizeName);


    if ((!ExternalName)      ||
        (*ExternalName == 0) ||
        (!ConvertedName))
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }

    /* Get the length of the new internal name */

    Info.ExternalName = ExternalName;
    AcpiNsGetInternalNameLength (&Info);

    /* We need a segment to store the internal  name */

    InternalName = ACPI_ALLOCATE_ZEROED (Info.Length);
    if (!InternalName)
    {
        return_ACPI_STATUS (AE_NO_MEMORY);
    }

    /* Build the name */

    Info.InternalName = InternalName;
    Status = AcpiNsBuildInternalName (&Info);
    if (ACPI_FAILURE (Status))
    {
        ACPI_FREE (InternalName);
        return_ACPI_STATUS (Status);
    }

    *ConvertedName = InternalName;
    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiNsExternalizeName
 *
 * PARAMETERS:  InternalNameLength  - Lenth of the internal name below
 *              InternalName        - Internal representation of name
 *              ConvertedNameLength - Where the length is returned
 *              ConvertedName       - Where the resulting external name
 *                                    is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
 *              to its external (printable) form (e.g. "\_PR_.CPU0")
 *
 ******************************************************************************/

ACPI_STATUS
AcpiNsExternalizeName (
    UINT32                  InternalNameLength,
    char                    *InternalName,
    UINT32                  *ConvertedNameLength,
    char                    **ConvertedName)
{
    ACPI_NATIVE_UINT        NamesIndex = 0;
    ACPI_NATIVE_UINT        NumSegments = 0;
    ACPI_NATIVE_UINT        RequiredLength;
    ACPI_NATIVE_UINT        PrefixLength = 0;
    ACPI_NATIVE_UINT        i = 0;
    ACPI_NATIVE_UINT        j = 0;


    ACPI_FUNCTION_TRACE (NsExternalizeName);


    if (!InternalNameLength     ||
        !InternalName           ||
        !ConvertedName)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }

    /*
     * Check for a prefix (one '\' | one or more '^').
     */
    switch (InternalName[0])
    {
    case '\\':
        PrefixLength = 1;
        break;

    case '^':
        for (i = 0; i < InternalNameLength; i++)
        {
            if (InternalName[i] == '^')
            {
                PrefixLength = i + 1;
            }
            else
            {
                break;
            }
        }

        if (i == InternalNameLength)
        {
            PrefixLength = i;
        }

        break;

    default:
        break;
    }

    /*
     * Check for object names.  Note that there could be 0-255 of these
     * 4-byte elements.
     */
    if (PrefixLength < InternalNameLength)
    {
        switch (InternalName[PrefixLength])
        {
        case AML_MULTI_NAME_PREFIX_OP:

            /* <count> 4-byte names */

            NamesIndex = PrefixLength + 2;
            NumSegments = (ACPI_NATIVE_UINT) (UINT8)
                          InternalName[(ACPI_NATIVE_UINT) (PrefixLength + 1)];
            break;

        case AML_DUAL_NAME_PREFIX:

            /* Two 4-byte names */

            NamesIndex = PrefixLength + 1;
            NumSegments = 2;
            break;

        case 0:

            /* NullName */

            NamesIndex = 0;
            NumSegments = 0;
            break;

        default:

            /* one 4-byte name */

            NamesIndex = PrefixLength;
            NumSegments = 1;
            break;
        }
    }

    /*
     * Calculate the length of ConvertedName, which equals the length
     * of the prefix, length of all object names, length of any required
     * punctuation ('.') between object names, plus the NULL terminator.
     */
    RequiredLength = PrefixLength + (4 * NumSegments) +
                        ((NumSegments > 0) ? (NumSegments - 1) : 0) + 1;

    /*
     * Check to see if we're still in bounds.  If not, there's a problem
     * with InternalName (invalid format).
     */
    if (RequiredLength > InternalNameLength)
    {
        ACPI_ERROR ((AE_INFO, "Invalid internal name"));
        return_ACPI_STATUS (AE_BAD_PATHNAME);
    }

    /*
     * Build ConvertedName