[bb] Online Patcher using the recursive CRC-32 builder by ozak [ 1+ years ago ]

[BlitzBot]

Title : Online Patcher using the recursive CRC-32 builder
Author : ozak
Posted : 1+ years ago

Description : Use my recursive CRC-32 file builder to build a patch info file.
Place it on your webserver and use this patcher to download changed files.

Code :

Code (blitzbasic) Select Expand

; HTTP Patcher for use with BuildCRC by Odin Jensen (www.furi.dk)

; Global config
Global url$ = "http://www.yourwebsitehere.com"
Global patchDir$ = "yourpatchdirhere"
Global aTitle$ = "HTTP Patcher v1.0"
Global winTitle$ = "HTTP Patcher v1.0 by Odin Jensen"
Global gameExe$ = "game.exe"

; Global control handles
Global patchBtn
Global playBtn
Global curProgBar
Global totalProgBar
Global infoBox

; Number of files to be patched
Global numFiles# = 0

; Download bank
Global bank=CreateBank(16384)

; File storage struct
Type FileEntry

Field fileName$

End Type

; Initialize CRC table
Dim CRC32_table(255)
CRC32_init()

; Create main window and controls
InitApp()

; Main loop
While WaitEvent()<>$803

; Was it a gadget action event?
If (EventID()=$401)

; Play button
If (EventSource()=playBtn)
ExecFile(gameExe)
End If

; Patch button
If (EventSource()=patchBtn)
; Connected
AddGadgetItem(infoBox,"Retrieving patch information.")

; Get patch info file
If (GetHTTPFile("patchinfo.dat") = False)
AddGadgetItem(infoBox, "Error: Could not retrieve patch information")
Else
; Inform the user of our progress
AddGadgetItem(infoBox, "Patch information retrieved ok.")
AddGadgetItem(infoBox, "Scanning files.")

; Read and check files
inFile = OpenFile("patchinfo.dat")

While (Not Eof(inFile))

; Read entry
curLine$ = ReadLine(inFile)
fe.FileEntry = New FileEntry
fefileName = Left(curLine, Instr(curLine,",")-1)
CRC$ = Mid(curLine, Instr(curLine, ",")+1, Len(curLine))

; Check CRC
fileCRC$ = Hex(CRC32_FromFile(fefileName))
If (Not fileCRC = CRC)
AddGadgetItem(infoBox, "File '" +  fefileName + "' needs patching.")
numFiles=numFiles+1
Else
AddGadgetItem(infoBox, "File '" +  fefileName + "' is up to date.")
Delete(fe)
End If

Wend

; Close file
CloseFile(infile)

; Patch those files
If (numFiles <> 0)
AddGadgetItem(infoBox, "Patching files.")
End If

progPos = 0
For fe.FileEntry=Each FileEntry

GetHTTPFile(fefileName)
progPos=progPos+1
UpdateProgBar(totalProgBar,progPos/numFiles)

Next

; Patching done
UpdateProgBar(totalProgBar,1)
AddGadgetItem(infoBox, "Ready to play!")
EnableGadget(playBtn)
DisableGadget(patchBtn)

; Delete patch info file
DeleteFile("patchInfo.dat")
End If
EndIf
EndIf

Wend


; Create main window and controls function
Function InitApp()

; Set app title
AppTitle(aTitle)

; Create main window
mainWindow=CreateWindow(winTitle,(ClientWidth (Desktop ()) / 2) - 200,(ClientHeight (Desktop ()) / 2) - 200,400,400,0,1)

; Create canvas
mainCanvas = CreateCanvas(0,0,GadgetWidth(mainWindow),GadgetHeight(mainWindow),mainWindow,0)

; Setup canvas for drawing
SetBuffer(CanvasBuffer(mainCanvas))
Color(100,100,100)
Rect(0,0,GadgetWidth(mainWindow),GadgetHeight(mainWindow))

; Create labels
Color(255,255,255)
Text(5, 10, "Total progress")
Text(5, 65, "Current progress")
Text(5, 120, "Information")

; Create progress bars
totalProgBar=CreateProgBar(5, 30, GadgetWidth(mainWindow) - 16, 20, mainCanvas)
curProgBar=CreateProgBar(5, 85, GadgetWidth(mainWindow) - 16, 20, mainCanvas)

; Create listbox for information
infoBox=CreateListBox(5, 140, GadgetWidth(mainWindow) - 16, GadgetHeight(mainWindow) - 200, mainCanvas)

; Create buttons
patchBtn=CreateButton("Patch", 5, GadgetHeight(mainWindow) - 50, 50, 20, mainCanvas)
playBtn=CreateButton("Play", GadgetWidth(mainWindow) - 60, GadgetHeight(mainWindow) - 50, 50, 20, mainCanvas)
DisableGadget(playBtn)

; Add some start info
AddGadgetItem(infoBox, "Welcome to the patcher. Click the patch button to begin.")

; Update canvas
FlipCanvas(mainCanvas)

End Function

; Get HTTP file function
Function GetHTTPFile(fileName$)

; Open stream
tcpStream=OpenTCPStream(url,80)

; Get and write patch info file
WriteLine tcpStream,"GET "+url+patchDir+"/"+fileName+" HTTP/1.0"
WriteLine tcpStream,Chr$(10)

; Error?
If (Eof(tcpStream))
Return False
End If

; Open file for writing
error=False
Local temp$
Local size# = 0

; Read header
Repeat
; Read next HTTP line
temp = ReadLine$(tcpStream)

; If we got a 404 Not Found, the file is missing from the server (or mispelled somewhere :)
If (Instr(temp, "404 Not Found")) error=True

; Get size
If  (Instr(temp, "Content-Length"))
size = Mid(temp, Instr(temp,": ")+2, Len(temp))
End If

; End of header
If (temp = "")

Exit

End If

Forever

; Error?
If (error)
Return False
End If

; Read and write file
Local outfile = WriteFile(fileName)

progPos = 0
While (Not Eof(tcpStream))
n=ReadBytes(bank,tcpStream,0,16384)
WriteBytes(bank,outfile,0,n)
progPos=progPos+n
UpdateProgBar(curProgBar,progPos/size)
Wend

CloseFile(outfile)

; Close stream
CloseTCPStream(tcpStream)

; All went well
Return True

End Function

; CRC init function
Function CRC32_Init()

  Local i
  Local j
  Local value

  For i=0 To 255
    value=i
    For j=0 To 7
      If (value And $1) Then
        value=(value Shr 1) Xor $EDB88320
      Else
        value=(value Shr 1)
      EndIf
    Next
    CRC32_table(i)=value
  Next
 
End Function

; Function to get CRC-32 value from a file
Function CRC32_FromFile(name$)

  Local byte
  Local crc
  Local file

  crc=$FFFFFFFF
  file=ReadFile(name$)
  If file=0 Then Return
  While Not Eof(file)
    byte=ReadByte(file)
    crc=(crc Shr 8) Xor CRC32_table(byte Xor (crc And $FF))
  Wend
  Return ~crc
 
End Function

Comments :


Xzider(Posted 1+ years ago)

 looks cool.. but Function waitevent() not found ?


ozak(Posted 1+ years ago)

 Better late than never. It's Blitz2D code


Damien Sturdy(Posted 1+ years ago)

 You mean B+


ozak(Posted 1+ years ago)

 Yes. Yes I do