The Trunk: Compression-ar.21.mcz

Andreas Raab uploaded a new version of Compression to project The Trunk:
http://source.squeak.org/trunk/Compression-ar.21.mcz

==================== Summary ====================

Name: Compression-ar.21
Author: ar
Time: 1 September 2010, 11:32:08.32 pm
UUID: fa1a526b-c5a4-4b43-a077-c53bf02c65da
Ancestors: Compression-ar.20

Break the dependency between the Collection and the Compression package.

=============== Diff against Compression-ar.20 ===============

Item was added:
+ ----- Method: PositionableStream>>asZLibReadStream (in category '*Compression') -----
+ asZLibReadStream
+ ^ZLibReadStream on: collection from: position+1 to: readLimit!

Item was added:
+ ----- Method: ReadWriteStream>>isZipArchive (in category '*Compression') -----
+ isZipArchive
+ "Determine if this appears to be a valid Zip archive"
+ | sig |
+ self binary.
+ sig := self next: 4.
+ self position: self position - 4. "rewind"
+ ^ZipArchive validSignatures includes: sig!

Item was added:
+ ----- Method: ReadWriteStream>>asUnZippedStream (in category '*Compression') -----
+ asUnZippedStream
+ | isGZip outputStream first strm archive which |
+ "Decompress this file if needed, and return a stream.  No file is written.  File extension may be .gz or anything else.  Also works on archives (.zip, .gZip)."
+
+ strm := self binary.
+ strm isZipArchive ifTrue: [
+ archive := ZipArchive new readFrom: strm.
+ which := archive members detect: [:any | any fileName asLowercase endsWith: '.ttf']
+ ifNone: [nil].
+ which ifNil: [archive close.
+ ^ self error: 'Can''t find .ttf file in archive'].
+ strm := which contentStream.
+ archive close].
+
+ first := strm next.
+ isGZip := (strm next * 256 + first) = (GZipConstants gzipMagic).
+ strm skip: -2.
+ isGZip
+ ifTrue: [outputStream := (MultiByteBinaryOrTextStream with:
+ (GZipReadStream on: strm) upToEnd) reset.
+ strm close]
+ ifFalse: [outputStream := strm].
+ ^ outputStream!

Item was added:
+ ----- Method: String>>unzipped (in category '*Compression') -----
+ unzipped
+ | magic1 magic2 |
+ magic1 := (self at: 1) asInteger.
+ magic2 := (self at: 2) asInteger.
+ (magic1 = 16r1F and:[magic2 = 16r8B]) ifFalse:[^self].
+ ^(GZipReadStream on: self) upToEnd!

Item was added:
+ ----- Method: String>>zipped (in category '*Compression') -----
+ zipped
+ | stream gzstream |
+
+ stream := RWBinaryOrTextStream on: String new.
+
+ gzstream := GZipWriteStream on: stream.
+ gzstream nextPutAll: self.
+ gzstream close.
+ stream reset.
+
+ ^ stream contents.
+ !