modhashtablehelpers.bas

这是一个在vb下实现的各种加密程序,可以实现一般的文本加密和文件加密,但是很多算法都是已经被人破解过的.

Attribute VB_Name = "modHashtableHelpers"
'    CopyRight (c) 2004 Kelly Ethridge
'
'    This file is part of VBCorLib.
'
'    VBCorLib is free software; you can redistribute it and/or modify
'    it under the terms of the GNU Library General Public License as published by
'    the Free Software Foundation; either version 2.1 of the License, or
'    (at your option) any later version.
'
'    VBCorLib is distributed in the hope that it will be useful,
'    but WITHOUT ANY WARRANTY; without even the implied warranty of
'    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
'    GNU Library General Public License for more details.
'
'    You should have received a copy of the GNU Library General Public License
'    along with Foobar; if not, write to the Free Software
'    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
'
'    Module: modHashtableHelpers
'
Option Explicit

Public Enum BucketStateEnum
    bsEmpty
    bsOccupied
    bsDeleted
End Enum

Public Type Bucket
    Key As Variant
    Value As Variant
    hashcode As Long
    State As BucketStateEnum
End Type

Private mPrimes(0 To 71)    As Long
Private mInited             As Boolean

''
' Returns the next prime number above the requested size.
'
' @param Value The requested value.
' @return The next prime above the requested value.
' @remarks The internal array of the Hashtable is
' incremented to the next prime above the requested size.
'
Public Function GetPrime(ByVal Value As Long) As Long
    If Not mInited Then InitPrimes
        
    ' we'll do a very fast binary search locally.
    Dim hi As Long
    Dim lo As Long
    Dim md As Long
    hi = 71
    Do While lo <= hi
        md = (lo + hi) \ 2
        Select Case mPrimes(md)
            Case Value
                GetPrime = Value
                Exit Function
            Case Is > Value
                hi = md - 1
            Case Else
                lo = md + 1
        End Select
    Loop
    
    If md < 0 Then md = Not md
    GetPrime = mPrimes(md)
End Function

''
' Init our set of primes
'
Private Sub InitPrimes()
   mPrimes(0) = 13
   mPrimes(1) = 17
   mPrimes(2) = 23
   mPrimes(3) = 29
   mPrimes(4) = 41
   mPrimes(5) = 53
   mPrimes(6) = 67
   mPrimes(7) = 89
   mPrimes(8) = 113
   mPrimes(9) = 149
   mPrimes(10) = 191
   mPrimes(11) = 251
   mPrimes(12) = 317
   mPrimes(13) = 409
   mPrimes(14) = 541
   mPrimes(15) = 691
   mPrimes(16) = 907
   mPrimes(17) = 1171
   mPrimes(18) = 1523
   mPrimes(19) = 1973
   mPrimes(20) = 2557
   mPrimes(21) = 3323
   mPrimes(22) = 4327
   mPrimes(23) = 5623
   mPrimes(24) = 7283
   mPrimes(25) = 9461
   mPrimes(26) = 12289
   mPrimes(27) = 15971
   mPrimes(28) = 20743
   mPrimes(29) = 26947
   mPrimes(30) = 35023
   mPrimes(31) = 45481
   mPrimes(32) = 59029
   mPrimes(33) = 76673
   mPrimes(34) = 99607
   mPrimes(35) = 129379
   mPrimes(36) = 168067
   mPrimes(37) = 218287
   mPrimes(38) = 283553
   mPrimes(39) = 368323
   mPrimes(40) = 478427
   mPrimes(41) = 621451
   mPrimes(42) = 807241
   mPrimes(43) = 1048583
   mPrimes(44) = 1362059
   mPrimes(45) = 1769281
   mPrimes(46) = 2298209
   mPrimes(47) = 2985287
   mPrimes(48) = 3877763
   mPrimes(49) = 5037091
   mPrimes(50) = 6542959
   mPrimes(51) = 8499037
   mPrimes(52) = 11039929
   mPrimes(53) = 14340433
   mPrimes(54) = 18627667
   mPrimes(55) = 24196619
   mPrimes(56) = 31430473
   mPrimes(57) = 40826971
   mPrimes(58) = 53032703
   mPrimes(59) = 68887367
   mPrimes(60) = 89482037
   mPrimes(61) = 116233673
   mPrimes(62) = 150983087
   mPrimes(63) = 196121153
   mPrimes(64) = 254753797
   mPrimes(65) = 330915313
   mPrimes(66) = 429846191
   mPrimes(67) = 558353591
   mPrimes(68) = 725279729
   mPrimes(69) = 942110419
   mPrimes(70) = 1223764877
   mPrimes(71) = 2147483647
   mInited = True
End Sub