- Joined
- Jun 24, 2017
- Messages
- 184
Somebody asked about this so I'll post what I use. The Test function at the end should show how to use it.
Code:
Strict
' Improved serialisation code
' For Android it seems I can't use 8-bit chars freely
Import mojo.app
Private
Global writeStack:Stack< Int >
Global readArray:Int[]
Global readLength:Int
Global index:Int
Global readError:Bool
Public
Function _____________________________________________Setup_________________________________________:Void()
End
Function StartWrite:Void( version:Int = 0 )
If writeStack = Null
writeStack = New Stack< Int >()
End
writeStack.Clear()
WriteInt( version )
End
Function FinishWrite:Void()
SaveState( MakeSaveString( writeStack.ToArray() ) )
End
Function StartRead:Int()
readArray = MakeLoadArray( LoadState() )
readLength = readArray.Length()
index = 0
readError = False
Return ReadInt()
End
Function WasReadError:Bool()
Return readError
End
Function AllRead:Bool()
Return index >= readLength
End
' Stretch string into half-bytes
Function MakeSaveString:String( data:Int[] )
Local BASE:Int = "A"[ 0 ]
Local len:Int = data.Length()
Local stretch:Int[] = New Int[ len * 2 ]
Local index:Int
For Local i:Int = 0 Until len
Local val:Int = data[ i ]
stretch[ index ] = BASE + val Shr 4
index += 1
stretch[ index ] = BASE + ( val & 15 )
index += 1
Next
Return String.FromChars( stretch )
End
' Compress back to bytes
Function MakeLoadArray:Int[]( str:String )
Local BASE:Int = "A"[ 0 ]
Local stretch:Int[] = str.ToChars()
Local data:Int[] = New Int[ stretch.Length() / 2 ]
Local len:Int = data.Length()
Local index:Int
For Local i:Int = 0 Until len
Local xx:Int = stretch[ index ]
Local val:Int = ( xx - BASE ) Shl 4
index += 1
xx = stretch[ index ]
val |= xx - BASE
index += 1
data[ i ] = val
Next
Return data
End
Private
Function _____________________________________________Private_______________________________________:Void()
End
Function ReadVal:Int()
If index >= readLength
readError = True
End
If readError
Return 0
End
Local val:Int = readArray[ index ]
index += 1
Return val
End
Function ReadVals:Int[]( nVals:Int )
If index + nVals > readLength
readError = True
End
If readError
Return New Int[ nVals ]
End
Local vals:Int[] = readArray[ index .. index + nVals ]
index += nVals
Return vals
End
Public
Function _____________________________________________Types_________________________________________:Void()
End
Function WriteByte:Void( val:Int )
writeStack.Push( val )
End
Function ReadByte:Int()
Return ReadVal()
End
Function WriteShort:Void( val:Int )
writeStack.Push( ( val Shr 8 ) & $FF )
writeStack.Push( val & $FF )
End
Function ReadShort:Int()
Local vals:Int[] = ReadVals( 2 )
Return ( vals[ 0 ] Shl 8 ) | vals[ 1 ]
End
Function WriteInt:Void( val:Int )
writeStack.Push( ( val Shr 24 ) & $FF )
writeStack.Push( ( val Shr 16 ) & $FF )
writeStack.Push( ( val Shr 8 ) & $FF )
writeStack.Push( val & $FF )
End
Function ReadInt:Int()
Local vals:Int[] = ReadVals( 4 )
Return ( vals[ 0 ] Shl 24 ) | ( vals[ 1 ] Shl 16 ) | ( vals[ 2 ] Shl 8 ) | vals[ 3 ]
End
Function WriteBool:Void( val:Bool )
If val
writeStack.Push( 1 )
Else
writeStack.Push( 0 )
End
End
Function ReadBool:Bool()
Return ReadVal() <> 0
End
Function WriteString:Void( str:String )
Local chars:Int[] = str.ToChars()
Local len:Int = chars.Length()
WriteInt( len )
For Local i:Int = 0 Until len
writeStack.Push( chars[ i ] )
Next
End
Function ReadString:String()
Local len:Int = ReadInt()
If len > 0
Return String.FromChars( ReadVals( len ) )
Else
Return ""
End
End
Function _____________________________________________Test__________________________________________:Void()
End
Function TestReadWrite:Void()
StartWrite( 10 )
WriteInt( 100 )
WriteInt( 1000000000 )
WriteInt( -1 )
WriteByte( 7 )
WriteShort( 983 )
WriteShort( -1 )
WriteString( "string" )
WriteBool( True )
FinishWrite()
Print StartRead()
Print "------"
Print ReadInt()
Print ReadInt()
Print ReadInt()
Print ReadByte()
Print ReadShort()
Print ReadShort()
Print ReadString()
If ReadBool() Then Print "True" Else Print "False"
If AllRead() And Not WasReadError() Then Print "Good" Else Print "Bad"
End