830 lines
26 KiB
C
830 lines
26 KiB
C
/*++
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Copyright (c) 1991 Microsoft Corporation
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Module Name:
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wild.c
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Abstract:
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This module implements functions to process wildcard specifiers.
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Author:
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Vijesh
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Revision History:
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--*/
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//
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// These following bit values are set in the FsRtlLegalDbcsCharacterArray
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//
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#define FSRTL_FAT_LEGAL 0x01
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#define FSRTL_HPFS_LEGAL 0x02
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#define FSRTL_NTFS_LEGAL 0x04
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#define FSRTL_WILD_CHARACTER 0x08
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#define FSRTL_OLE_LEGAL 0x10
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#define FSRTL_NTFS_STREAM_LEGAL (FSRTL_NTFS_LEGAL | FSRTL_OLE_LEGAL)
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//
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// The global static legal ANSI character array. Wild characters
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// are not considered legal, they should be checked seperately if
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// allowed.
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//
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#define _FAT_ FSRTL_FAT_LEGAL
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#define _HPFS_ FSRTL_HPFS_LEGAL
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#define _NTFS_ FSRTL_NTFS_LEGAL
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#define _OLE_ FSRTL_OLE_LEGAL
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#define _WILD_ FSRTL_WILD_CHARACTER
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static const UCHAR LocalLegalAnsiCharacterArray[128] = {
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0 , // 0x00 ^@
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_OLE_, // 0x01 ^A
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_OLE_, // 0x02 ^B
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_OLE_, // 0x03 ^C
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_OLE_, // 0x04 ^D
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_OLE_, // 0x05 ^E
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_OLE_, // 0x06 ^F
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_OLE_, // 0x07 ^G
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_OLE_, // 0x08 ^H
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_OLE_, // 0x09 ^I
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_OLE_, // 0x0A ^J
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_OLE_, // 0x0B ^K
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_OLE_, // 0x0C ^L
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_OLE_, // 0x0D ^M
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_OLE_, // 0x0E ^N
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_OLE_, // 0x0F ^O
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_OLE_, // 0x10 ^P
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_OLE_, // 0x11 ^Q
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_OLE_, // 0x12 ^R
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_OLE_, // 0x13 ^S
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_OLE_, // 0x14 ^T
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_OLE_, // 0x15 ^U
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_OLE_, // 0x16 ^V
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_OLE_, // 0x17 ^W
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_OLE_, // 0x18 ^X
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_OLE_, // 0x19 ^Y
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_OLE_, // 0x1A ^Z
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_OLE_, // 0x1B ESC
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_OLE_, // 0x1C FS
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_OLE_, // 0x1D GS
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_OLE_, // 0x1E RS
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_OLE_, // 0x1F US
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x20 space
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_FAT_ | _HPFS_ | _NTFS_ , // 0x21 !
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_WILD_| _OLE_, // 0x22 "
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x23 #
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x24 $
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x25 %
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x26 &
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x27 '
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x28 (
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x29 )
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_WILD_| _OLE_, // 0x2A *
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_HPFS_ | _NTFS_ | _OLE_, // 0x2B +
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_HPFS_ | _NTFS_ | _OLE_, // 0x2C ,
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x2D -
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_FAT_ | _HPFS_ | _NTFS_ , // 0x2E .
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0 , // 0x2F /
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x30 0
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x31 1
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x32 2
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x33 3
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x34 4
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x35 5
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x36 6
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x37 7
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x38 8
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x39 9
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_NTFS_ , // 0x3A :
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_HPFS_ | _NTFS_ | _OLE_, // 0x3B ;
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_WILD_| _OLE_, // 0x3C <
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_HPFS_ | _NTFS_ | _OLE_, // 0x3D =
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_WILD_| _OLE_, // 0x3E >
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_WILD_| _OLE_, // 0x3F ?
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x40 @
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x41 A
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x42 B
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x43 C
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x44 D
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x45 E
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x46 F
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x47 G
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x48 H
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x49 I
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4A J
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4B K
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4C L
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4D M
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4E N
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x4F O
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x50 P
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x51 Q
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x52 R
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x53 S
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x54 T
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x55 U
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x56 V
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x57 W
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x58 X
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x59 Y
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x5A Z
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_HPFS_ | _NTFS_ | _OLE_, // 0x5B [
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0 , // 0x5C backslash
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_HPFS_ | _NTFS_ | _OLE_, // 0x5D ]
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x5E ^
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x5F _
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x60 `
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x61 a
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x62 b
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x63 c
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x64 d
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x65 e
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x66 f
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x67 g
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x68 h
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x69 i
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6A j
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6B k
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6C l
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6D m
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6E n
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x6F o
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x70 p
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x71 q
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x72 r
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x73 s
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x74 t
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x75 u
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x76 v
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x77 w
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x78 x
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x79 y
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x7A z
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x7B {
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0 | _OLE_, // 0x7C |
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x7D }
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x7E ~
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_FAT_ | _HPFS_ | _NTFS_ | _OLE_, // 0x7F
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};
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UCHAR const* const FsRtlLegalAnsiCharacterArray = &LocalLegalAnsiCharacterArray[0];
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#define LEGAL_ANSI_CHARACTER_ARRAY (FsRtlLegalAnsiCharacterArray)
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#define mQueryBits(uFlags, uBits) ((uFlags) & (uBits))
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#define FlagOn(uFlags, uBit) (mQueryBits(uFlags, uBit) != 0)
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#define IsUnicodeCharacterWild(C) ( \
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(((C) >= 0x40) ? FALSE : FlagOn( LEGAL_ANSI_CHARACTER_ARRAY[(C)], \
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FSRTL_WILD_CHARACTER ) ) \
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)
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typedef struct _UNICODE_STRING {
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USHORT Length;
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USHORT MaximumLength;
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PWSTR Buffer;
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} UNICODE_STRING, *PUNICODE_STRING;
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#define DOS_STAR TEXT('<')
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#define DOS_QM TEXT('>')
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#define DOS_DOT TEXT('"')
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BOOLEAN
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DoesNameContainWildCards (
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IN PTSTR Name
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)
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/*++
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Routine Description:
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This routine simply scans the input Name string looking for any Nt
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wild card characters.
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Arguments:
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Name - The string to check.
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Return Value:
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BOOLEAN - TRUE if one or more wild card characters was found.
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--*/
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{
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PTCHAR p;
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//
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// Check each character in the name to see if it's a wildcard
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// character.
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//
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if( lstrlen(Name) ) {
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for( p = Name + lstrlen(Name) - 1;
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p >= Name && *p != TEXT('\\') ;
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p-- ) {
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//
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// check for a wild card character
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//
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if (IsUnicodeCharacterWild( *p )) {
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//
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// Tell caller that this name contains wild cards
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//
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return TRUE;
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}
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}
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}
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//
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// No wildcard characters were found, so return to our caller
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//
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return FALSE;
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}
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BOOLEAN
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IsNameInExpressionPrivate (
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IN PCTSTR Expression,
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IN PCTSTR Name
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)
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/*++
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Routine Description:
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This routine compares a Dbcs name and an expression and tells the caller
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if the name is in the language defined by the expression. The input name
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cannot contain wildcards, while the expression may contain wildcards.
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Expression wild cards are evaluated as shown in the nondeterministic
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finite automatons below. Note that ~* and ~? are DOS_STAR and DOS_QM.
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~* is DOS_STAR, ~? is DOS_QM, and ~. is DOS_DOT
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S
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<-----<
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X | | e Y
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X * Y == (0)----->-(1)->-----(2)-----(3)
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S-.
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<-----<
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X | | e Y
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X ~* Y == (0)----->-(1)->-----(2)-----(3)
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X S S Y
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X ?? Y == (0)---(1)---(2)---(3)---(4)
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X . . Y
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X ~.~. Y == (0)---(1)----(2)------(3)---(4)
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| |________|
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| ^ |
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|_______________|
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^EOF or .^
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X S-. S-. Y
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X ~?~? Y == (0)---(1)-----(2)-----(3)---(4)
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| |________|
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| ^ |
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|_______________|
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^EOF or .^
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where S is any single character
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S-. is any single character except the final .
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e is a null character transition
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EOF is the end of the name string
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In words:
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* matches 0 or more characters.
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? matches exactly 1 character.
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DOS_STAR matches 0 or more characters until encountering and matching
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the final . in the name.
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DOS_QM matches any single character, or upon encountering a period or
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end of name string, advances the expression to the end of the
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set of contiguous DOS_QMs.
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DOS_DOT matches either a . or zero characters beyond name string.
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Arguments:
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Expression - Supplies the input expression to check against
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(Caller must already upcase if passing CaseInsensitive TRUE.)
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Name - Supplies the input name to check for.
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CaseInsensitive - TRUE if Name should be Upcased before comparing.
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Return Value:
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BOOLEAN - TRUE if Name is an element in the set of strings denoted
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by the input Expression and FALSE otherwise.
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--*/
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{
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USHORT NameOffset;
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USHORT ExprOffset;
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ULONG SrcCount;
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ULONG DestCount;
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ULONG PreviousDestCount;
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ULONG MatchesCount;
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TCHAR NameChar, ExprChar;
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USHORT LocalBuffer[16 * 2];
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USHORT *AuxBuffer = NULL;
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USHORT *PreviousMatches;
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USHORT *CurrentMatches;
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USHORT MaxState;
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USHORT CurrentState;
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BOOLEAN NameFinished = FALSE;
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ULONG NameLen, ExpressionLen;
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//
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// The idea behind the algorithm is pretty simple. We keep track of
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// all possible locations in the regular expression that are matching
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// the name. If when the name has been exhausted one of the locations
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// in the expression is also just exhausted, the name is in the language
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// defined by the regular expression.
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//
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NameLen = lstrlen(Name)*sizeof(TCHAR);
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ExpressionLen = lstrlen(Expression)*sizeof(TCHAR);
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//
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// If one string is empty return FALSE. If both are empty return TRUE.
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//
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if ( (NameLen == 0) || (ExpressionLen == 0) ) {
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return (BOOLEAN)(!(NameLen + ExpressionLen));
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}
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//
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// Special case by far the most common wild card search of *
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//
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if ((ExpressionLen == 2) && (Expression[0] == TEXT('*'))) {
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return TRUE;
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}
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//
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// Also special case expressions of the form *X. With this and the prior
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// case we have covered virtually all normal queries.
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//
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if (Expression[0] == TEXT('*')) {
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TCHAR LocalExpression[MAX_PATH];
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ULONG LocalExpressionLen;
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lstrcpy( LocalExpression, Expression+1);
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LocalExpressionLen = lstrlen( LocalExpression )*sizeof(TCHAR);
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//
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// Only special case an expression with a single *
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//
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if ( !DoesNameContainWildCards( LocalExpression ) ) {
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ULONG StartingNameOffset;
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if (NameLen < (USHORT)(ExpressionLen-sizeof(TCHAR))) {
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return FALSE;
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}
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StartingNameOffset = ( NameLen -
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LocalExpressionLen )/sizeof(TCHAR);
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//
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// Do a simple memory compare if case sensitive, otherwise
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// we have got to check this one character at a time.
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//
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return (BOOLEAN) RtlEqualMemory( LocalExpression,
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Name + StartingNameOffset,
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LocalExpressionLen );
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}
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}
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//
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// Walk through the name string, picking off characters. We go one
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// character beyond the end because some wild cards are able to match
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// zero characters beyond the end of the string.
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//
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// With each new name character we determine a new set of states that
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// match the name so far. We use two arrays that we swap back and forth
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// for this purpose. One array lists the possible expression states for
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// all name characters up to but not including the current one, and other
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// array is used to build up the list of states considering the current
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// name character as well. The arrays are then switched and the process
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// repeated.
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//
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// There is not a one-to-one correspondence between state number and
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// offset into the expression. This is evident from the NFAs in the
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// initial comment to this function. State numbering is not continuous.
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// This allows a simple conversion between state number and expression
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// offset. Each character in the expression can represent one or two
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// states. * and DOS_STAR generate two states: ExprOffset*2 and
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// ExprOffset*2 + 1. All other expreesion characters can produce only
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// a single state. Thus ExprOffset = State/2.
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//
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//
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// Here is a short description of the variables involved:
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//
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// NameOffset - The offset of the current name char being processed.
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//
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// ExprOffset - The offset of the current expression char being processed.
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//
|
||
// SrcCount - Prior match being investigated with current name char
|
||
//
|
||
// DestCount - Next location to put a matching assuming current name char
|
||
//
|
||
// NameFinished - Allows one more itteration through the Matches array
|
||
// after the name is exhusted (to come *s for example)
|
||
//
|
||
// PreviousDestCount - This is used to prevent entry duplication, see coment
|
||
//
|
||
// PreviousMatches - Holds the previous set of matches (the Src array)
|
||
//
|
||
// CurrentMatches - Holds the current set of matches (the Dest array)
|
||
//
|
||
// AuxBuffer, LocalBuffer - the storage for the Matches arrays
|
||
//
|
||
|
||
//
|
||
// Set up the initial variables
|
||
//
|
||
|
||
PreviousMatches = &LocalBuffer[0];
|
||
CurrentMatches = &LocalBuffer[16];
|
||
|
||
PreviousMatches[0] = 0;
|
||
MatchesCount = 1;
|
||
|
||
NameOffset = 0;
|
||
|
||
MaxState = (USHORT)(ExpressionLen * 2);
|
||
|
||
while ( !NameFinished ) {
|
||
|
||
if ( NameOffset < NameLen ) {
|
||
|
||
NameChar = Name[NameOffset / sizeof(TCHAR)];
|
||
|
||
NameOffset += sizeof(TCHAR);;
|
||
|
||
} else {
|
||
|
||
NameFinished = TRUE;
|
||
|
||
//
|
||
// if we have already exhasted the expression, cool. Don't
|
||
// continue.
|
||
//
|
||
|
||
if ( PreviousMatches[MatchesCount-1] == MaxState ) {
|
||
|
||
break;
|
||
}
|
||
}
|
||
|
||
|
||
//
|
||
// Now, for each of the previous stored expression matches, see what
|
||
// we can do with this name character.
|
||
//
|
||
|
||
SrcCount = 0;
|
||
DestCount = 0;
|
||
PreviousDestCount = 0;
|
||
|
||
while ( SrcCount < MatchesCount ) {
|
||
|
||
USHORT Length;
|
||
|
||
//
|
||
// We have to carry on our expression analysis as far as possible
|
||
// for each character of name, so we loop here until the
|
||
// expression stops matching. A clue here is that expression
|
||
// cases that can match zero or more characters end with a
|
||
// continue, while those that can accept only a single character
|
||
// end with a break.
|
||
//
|
||
|
||
ExprOffset = (USHORT)((PreviousMatches[SrcCount++] + 1) / 2);
|
||
|
||
|
||
Length = 0;
|
||
|
||
while ( TRUE ) {
|
||
|
||
if ( ExprOffset == ExpressionLen ) {
|
||
|
||
break;
|
||
}
|
||
|
||
//
|
||
// The first time through the loop we don't want
|
||
// to increment ExprOffset.
|
||
//
|
||
|
||
ExprOffset += Length;
|
||
Length = sizeof(TCHAR);
|
||
|
||
CurrentState = (USHORT)(ExprOffset * 2);
|
||
|
||
if ( ExprOffset == ExpressionLen ) {
|
||
|
||
CurrentMatches[DestCount++] = MaxState;
|
||
break;
|
||
}
|
||
|
||
ExprChar = Expression[ExprOffset / sizeof(TCHAR)];
|
||
|
||
|
||
//
|
||
// Before we get started, we have to check for something
|
||
// really gross. We may be about to exhaust the local
|
||
// space for ExpressionMatches[][], so we have to allocate
|
||
// some pool if this is the case. Yuk!
|
||
//
|
||
|
||
if ( (DestCount >= 16 - 2) &&
|
||
(AuxBuffer == NULL) ) {
|
||
|
||
ULONG ExpressionChars;
|
||
|
||
ExpressionChars = ExpressionLen / sizeof(TCHAR);
|
||
|
||
AuxBuffer = malloc( (ExpressionChars+1) * sizeof(USHORT)*2*2 );
|
||
|
||
RtlCopyMemory( AuxBuffer,
|
||
CurrentMatches,
|
||
16 * sizeof(USHORT) );
|
||
|
||
CurrentMatches = AuxBuffer;
|
||
|
||
RtlCopyMemory( AuxBuffer + (ExpressionChars+1)*2,
|
||
PreviousMatches,
|
||
16 * sizeof(USHORT) );
|
||
|
||
PreviousMatches = AuxBuffer + (ExpressionChars+1)*2;
|
||
}
|
||
|
||
//
|
||
// * matches any character zero or more times.
|
||
//
|
||
|
||
if (ExprChar == TEXT('*')) {
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
CurrentMatches[DestCount++] = CurrentState + 3;
|
||
continue;
|
||
}
|
||
|
||
//
|
||
// DOS_STAR matches any character except . zero or more times.
|
||
//
|
||
|
||
if (ExprChar == DOS_STAR) {
|
||
|
||
BOOLEAN ICanEatADot = FALSE;
|
||
|
||
//
|
||
// If we are at a period, determine if we are allowed to
|
||
// consume it, ie. make sure it is not the last one.
|
||
//
|
||
|
||
if ( !NameFinished && (NameChar == TEXT('.')) ) {
|
||
|
||
USHORT Offset;
|
||
|
||
for ( Offset = NameOffset;
|
||
Offset < NameLen;
|
||
Offset += Length ) {
|
||
|
||
if (Name[Offset / sizeof(TCHAR)] == TEXT('.')) {
|
||
|
||
ICanEatADot = TRUE;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (NameFinished || (NameChar != TEXT('.')) || ICanEatADot) {
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
CurrentMatches[DestCount++] = CurrentState + 3;
|
||
continue;
|
||
|
||
} else {
|
||
|
||
//
|
||
// We are at a period. We can only match zero
|
||
// characters (ie. the epsilon transition).
|
||
//
|
||
|
||
CurrentMatches[DestCount++] = CurrentState + 3;
|
||
continue;
|
||
}
|
||
}
|
||
|
||
//
|
||
// The following expreesion characters all match by consuming
|
||
// a character, thus force the expression, and thus state
|
||
// forward.
|
||
//
|
||
|
||
CurrentState += (USHORT)(sizeof(TCHAR) * 2);
|
||
|
||
//
|
||
// DOS_QM is the most complicated. If the name is finished,
|
||
// we can match zero characters. If this name is a '.', we
|
||
// don't match, but look at the next expression. Otherwise
|
||
// we match a single character.
|
||
//
|
||
|
||
if ( ExprChar == DOS_QM ) {
|
||
|
||
if ( NameFinished || (NameChar == TEXT('.')) ) {
|
||
|
||
continue;
|
||
}
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
break;
|
||
}
|
||
|
||
//
|
||
// A DOS_DOT can match either a period, or zero characters
|
||
// beyond the end of name.
|
||
//
|
||
|
||
if (ExprChar == DOS_DOT) {
|
||
|
||
if ( NameFinished ) {
|
||
|
||
continue;
|
||
}
|
||
|
||
if (NameChar == TEXT('.')) {
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
break;
|
||
}
|
||
}
|
||
|
||
//
|
||
// From this point on a name character is required to even
|
||
// continue, let alone make a match.
|
||
//
|
||
|
||
if ( NameFinished ) {
|
||
|
||
break;
|
||
}
|
||
|
||
//
|
||
// If this expression was a '?' we can match it once.
|
||
//
|
||
|
||
if (ExprChar == TEXT('?')) {
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
break;
|
||
}
|
||
|
||
//
|
||
// Finally, check if the expression char matches the name char
|
||
//
|
||
|
||
if (ExprChar == (TCHAR)(NameChar)) {
|
||
|
||
CurrentMatches[DestCount++] = CurrentState;
|
||
break;
|
||
}
|
||
|
||
//
|
||
// The expression didn't match so go look at the next
|
||
// previous match.
|
||
//
|
||
|
||
break;
|
||
}
|
||
|
||
|
||
//
|
||
// Prevent duplication in the destination array.
|
||
//
|
||
// Each of the arrays is montonically increasing and non-
|
||
// duplicating, thus we skip over any source element in the src
|
||
// array if we just added the same element to the destination
|
||
// array. This guarentees non-duplication in the dest. array.
|
||
//
|
||
|
||
if ((SrcCount < MatchesCount) &&
|
||
(PreviousDestCount < DestCount) ) {
|
||
|
||
while (PreviousDestCount < DestCount) {
|
||
|
||
while ( PreviousMatches[SrcCount] <
|
||
CurrentMatches[PreviousDestCount] ) {
|
||
|
||
SrcCount += 1;
|
||
}
|
||
|
||
PreviousDestCount += 1;
|
||
}
|
||
}
|
||
}
|
||
|
||
//
|
||
// If we found no matches in the just finished itteration, it's time
|
||
// to bail.
|
||
//
|
||
|
||
if ( DestCount == 0 ) {
|
||
|
||
if (AuxBuffer != NULL) { free( AuxBuffer ); }
|
||
|
||
return FALSE;
|
||
}
|
||
|
||
//
|
||
// Swap the meaning the two arrays
|
||
//
|
||
|
||
{
|
||
USHORT *Tmp;
|
||
|
||
Tmp = PreviousMatches;
|
||
|
||
PreviousMatches = CurrentMatches;
|
||
|
||
CurrentMatches = Tmp;
|
||
}
|
||
|
||
MatchesCount = DestCount;
|
||
}
|
||
|
||
|
||
CurrentState = PreviousMatches[MatchesCount-1];
|
||
|
||
if (AuxBuffer != NULL) { free( AuxBuffer ); }
|
||
|
||
|
||
return (BOOLEAN)(CurrentState == MaxState);
|
||
}
|
||
|
||
|