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;{ searchINfile
Structure ByteArray
   byte.b[0]
EndStructure

Declare.i QuickSearch (*mainMem.ByteArray, mainSize.i, *findMem.ByteArray, findSize.i, startOff.i=0)
Declare.q FindInFile (infile.i, *find, findSize.i, startOff.q=0, bufferSize.i=4096)
Declare.s GetFileString(File$,tagStart$, tagEnd$)


Procedure.i QuickSearch (*mainMem.ByteArray, mainSize.i, *findMem.ByteArray, findSize.i, startOff.i=0)
   ; -- Simplification of the Boyer-Moore algorithm;
   ;    searches for a sequence of bytes in memory
   ;    (not for characters, so it works in ASCII mode and Unicode mode)
   ; in : *mainMem: pointer to memory area where to search
   ;      mainSize: size of memory area where to search (bytes)
   ;      *findMem: pointer to byte sequence to search for
   ;      findSize: size of byte sequence to search for
   ;      startOff: offset in <mainMem>, where the search begins (bytes)
   ; Note: The first offset is 0 (not 1)!
   ; out: offset in <mainMem>, where <findMem> was found (bytes);
   ;      -1 if not found
   ;
   ; after <http://www-igm.univ-mlv.fr/~lecroq/string/node19.html#SECTION00190>, 31.8.2008
   ; (translated from C to PureBasic by Little John)
   Protected i.i, diff.i
   Dim badByte.i(255)
   
   ; Preprocessing
   For i = 0 To 255
      badByte(i) = findSize + 1
   Next
   For i = 0 To findSize - 1
      badByte(*findMem\byte[i] & #FF) = findSize - i
   Next
   
   ; Searching
   diff = mainSize - findSize
   While startOff <= diff
      If CompareMemory(*mainMem + startOff, *findMem, findSize) = 1
         ProcedureReturn startOff
      EndIf
      startOff + badByte(*mainMem\byte[startOff + findSize] & #FF)  ; shift
   Wend
   
   ProcedureReturn -1                                               ; not found
EndProcedure
Procedure.q FindInFile (infile.i, *find, findSize.i, startOff.q=0, bufferSize.i=4096)
   ; -- Looks in <infile> for byte sequence at *find;
   ;    works in ASCII mode and Unicode mode.
   ; in : infile    : number of a file, that was opened for reading
   ;      *find     : pointer to byte sequence to search for
   ;      findSize  : number of bytes to search for
   ;      startOff  : offset in the file where the search begins (bytes)
   ;      bufferSize: size of used memory buffer (bytes)
   ; Note: The first offset is 0 (not 1)!
   ; out: offset in the file, where byte sequence at *find was found (bytes),
   ;      -1 if byte sequence at *find was not found in <infile>,
   ;      -2 if <findSize> is bigger than <bufferSize>
   Protected *buffer
   Protected offset.q, move.i, bytes.i
   
   move = bufferSize - findSize + 1
   If move < 1
      ProcedureReturn -2                 ; error
   EndIf
   
   *buffer = AllocateMemory(bufferSize)
   Repeat
      FileSeek(infile, startOff)
      bytes = ReadData(infile, *buffer, bufferSize)
      ; QuickSearch returns the offset in the buffer (bytes),
      ; or -1 if not found:
      offset = QuickSearch(*buffer, bytes, *find, findSize)
      If offset <> -1                    ; found
         offset + startOff
         Break
      EndIf
      startOff + move
   Until bytes < bufferSize
   
   FreeMemory(*buffer)
   ProcedureReturn offset
EndProcedure
Procedure.s GetFileString(File$,tagStart$, tagEnd$)
  
  
ifn = ReadFile(#PB_Any, File$)
If ifn
  RETStart = FindInFile(ifn, @tagStart$, StringByteLength(tagStart$))
  Debug "RETStart:"+Str(RETStart) 
  
  If RETStart < 0
    CloseFile(ifn)
    ProcedureReturn ""
  EndIf
  
  If tagEnd$<>""
    RETEnd = FindInFile(ifn, @tagEnd$, StringByteLength(tagEnd$))
    Debug "RETEnd:"+Str(RETEnd) 
    
    
     If RETend<=0 
       RetVal$=""
       CloseFile(ifn)
       ProcedureReturn RetVal$
     EndIf
     
     
    FileSeek(ifn,RETStart+StringByteLength(tagStart$))
    RetVal$ = ReadString(ifn,#PB_UTF8,RETEnd-RETStart-StringByteLength(tagStart$)):RetVal$=Left(RetVal$,Len(RetVal$)-1)
    
  Else
    FileSeek(ifn,RETStart+StringByteLength(tagStart$)+1)
    RetVal$ = ReadString(ifn,#PB_UTF8,17)
  EndIf    
  CloseFile(ifn)
  
  ProcedureReturn RetVal$
Else
  ProcedureReturn "0"
EndIf
EndProcedure
;}