ACPI_STATUS AcpiUtValidateResource	(	void *	Aml,
		UINT8 *	ReturnIndex
	)
Definition at line 467 of file utresrc.c.
Referenced by AcpiRsConvertResourcesToAml(), AcpiRsGetListLength(), and AcpiUtWalkAmlResources().
{
    UINT8                   ResourceType;
    UINT8                   ResourceIndex;
    ACPI_RS_LENGTH          ResourceLength;
    ACPI_RS_LENGTH          MinimumResourceLength;


    ACPI_FUNCTION_ENTRY ();


    /*
     * 1) Validate the ResourceType field (Byte 0)
     */
    ResourceType = ACPI_GET8 (Aml);

    /*
     * Byte 0 contains the descriptor name (Resource Type)
     * Examine the large/small bit in the resource header
     */
    if (ResourceType & ACPI_RESOURCE_NAME_LARGE)
    {
        /* Verify the large resource type (name) against the max */

        if (ResourceType > ACPI_RESOURCE_NAME_LARGE_MAX)
        {
            return (AE_AML_INVALID_RESOURCE_TYPE);
        }

        /*
         * Large Resource Type -- bits 6:0 contain the name
         * Translate range 0x80-0x8B to index range 0x10-0x1B
         */
        ResourceIndex = (UINT8) (ResourceType - 0x70);
    }
    else
    {
        /*
         * Small Resource Type -- bits 6:3 contain the name
         * Shift range to index range 0x00-0x0F
         */
        ResourceIndex = (UINT8)
            ((ResourceType & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
    }

    /* Check validity of the resource type, zero indicates name is invalid */

    if (!AcpiGbl_ResourceTypes[ResourceIndex])
    {
        return (AE_AML_INVALID_RESOURCE_TYPE);
    }


    /*
     * 2) Validate the ResourceLength field. This ensures that the length
     *    is at least reasonable, and guarantees that it is non-zero.
     */
    ResourceLength = AcpiUtGetResourceLength (Aml);
    MinimumResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];

    /* Validate based upon the type of resource - fixed length or variable */

    switch (AcpiGbl_ResourceTypes[ResourceIndex])
    {
    case ACPI_FIXED_LENGTH:

        /* Fixed length resource, length must match exactly */

        if (ResourceLength != MinimumResourceLength)
        {
            return (AE_AML_BAD_RESOURCE_LENGTH);
        }
        break;

    case ACPI_VARIABLE_LENGTH:

        /* Variable length resource, length must be at least the minimum */

        if (ResourceLength < MinimumResourceLength)
        {
            return (AE_AML_BAD_RESOURCE_LENGTH);
        }
        break;

    case ACPI_SMALL_VARIABLE_LENGTH:

        /* Small variable length resource, length can be (Min) or (Min-1) */

        if ((ResourceLength > MinimumResourceLength) ||
            (ResourceLength < (MinimumResourceLength - 1)))
        {
            return (AE_AML_BAD_RESOURCE_LENGTH);
        }
        break;

    default:

        /* Shouldn't happen (because of validation earlier), but be sure */

        return (AE_AML_INVALID_RESOURCE_TYPE);
    }

    /* Optionally return the resource table index */

    if (ReturnIndex)
    {
        *ReturnIndex = ResourceIndex;
    }

    return (AE_OK);
}
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