GitHub/SWCompression
1
0
Fork 0
mirror of https://github.com/tsolomko/SWCompression.git synced 2026-06-23 14:56:41 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fixed memory problems in BZip2.

Browse Source
This commit is contained in:
Timofey Solomko
2016-11-15 23:45:38 +03:00
parent ec72622a86
commit fb2ec28f1a
1 changed files with 11 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Sources/BZip2.swift
+11 -14
View File
@@ -175,11 +175,10 @@ public class BZip2: DecompressionAlgorithm {
var decoded = 0
var repeat_ = 0
var repeatPower = 0
var buffer = Data()
var buffer: [UInt8] = []
var t: HuffmanTable?
while true {
// TODO: WTF is going on with `decoded`?
decoded -= 1
if decoded <= 0 {
decoded = 50
@@ -202,7 +201,7 @@ public class BZip2: DecompressionAlgorithm {
repeatPower <<= 1
continue
} else if repeat_ > 0 {
buffer.append(Array(repeating: favourites[0], count: repeat_), count: repeat_)
buffer.append(contentsOf: Array(repeating: favourites[0], count: repeat_))
repeat_ = 0
}
if symbol == symbolsInUse - 1 {
@@ -215,16 +214,14 @@ public class BZip2: DecompressionAlgorithm {
}
}
func bwt(transform data: Data) -> [Int] {
// TODO: Check performance with and without sorting.
let bytes = data.toArray(type: UInt8.self)
func bwt(transform bytes: [UInt8]) -> [Int] {
let sortedBytes = bytes.sorted()
var base: [Int] = Array(repeating: -1, count: 256)
for i in 0..<256 {
base[i] = sortedBytes.index(of: UInt8(truncatingBitPattern: UInt(i))) ?? -1
}
var pointers: [Int] = Array(repeating: -1, count: data.count)
var pointers: [Int] = Array(repeating: -1, count: bytes.count)
for (i, char) in bytes.enumerated() {
pointers[base[char.toInt()]] = i
base[char.toInt()] += 1
@@ -233,16 +230,16 @@ public class BZip2: DecompressionAlgorithm {
return pointers
}
func bwt(reverse data: Data, end: inout Int) -> Data {
var reversed = Data()
if data.count > 0 {
let T = bwt(transform: data)
for _ in 0..<data.count {
func bwt(reverse bytes: [UInt8], end: inout Int) -> [UInt8] {
var resultBytes: [UInt8] = []
if bytes.count > 0 {
let T = bwt(transform: bytes)
for _ in 0..<bytes.count {
end = T[end]
reversed.append(data[end])
resultBytes.append(bytes[end])
}
}
return reversed
return resultBytes
}
let nt = bwt(reverse: buffer, end: &pointer)