izaya/OC-PsychOS2
1
1
Fork 0
mirror of https://git.shadowkat.net/izaya/OC-PsychOS2.git synced 2024-11-21 19:44:21 -05:00
Code Issues Releases Wiki Activity

switched to using string.(un)pack in libmtar and liblz16, meaning it works on both big and little endian machines, and should be smaller and faster

Browse Source
This commit is contained in:
XeonSquared 2021-05-26 16:15:24 +10:00
parent c5f304380e
commit 8e84eb0c67
2 changed files with 5 additions and 42 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
lib/liblz16.lua
View File

@ -3,31 +3,13 @@ local buffer = require "buffer"
lz16 = {}
local function cint(n,l)
local t={}
for i = 0, 7 do
t[i+1] = (n >> (i * 8)) & 0xFF
end
return string.reverse(string.char(table.unpack(t)):sub(1,l))
end
local function toint(s)
local n = 0
local i = 1
for p in s:gmatch(".") do
n = n << 8
n = n | string.byte(p)
i=i+1
end
return n
end
local function readBuffer(fi)
local stream = {}
if fi:read(4) ~= "lz16" then
return false, "not an lz16 archive"
end
function stream.read()
local len = toint(fi:read(2) or "\0\0")
local len = string.unpack(">I2", fi:read(2) or "\0\0")
if len < 1 then
return nil
end
@ -44,7 +26,7 @@ local function writeBuffer(fo)
local stream = {}
function stream:write(data)
local cblock = lz.compress(data)
fo:write(cint(cblock:len(),2)..cblock)
fo:write(string.pack(">I2", cblock:len()) .. cblock)
return cblock:len()+2
end
function stream.close()

25
lib/libmtar.lua
View File

@ -1,24 +1,5 @@
local mtar = {}
local function toint(s)
local n = 0
local i = 1
for p in s:gmatch(".") do
n = n << 8
n = n | string.byte(p)
i=i+1
end
return n
end
local function cint(n,l)
local t={}
for i = 0, 7 do
t[i+1] = (n >> (i * 8)) & 0xFF
end
return string.reverse(string.char(table.unpack(t)):sub(1,l))
end
local function cleanPath(path)
local pt = {}
for segment in path:gmatch("[^/]+") do
@ -32,7 +13,7 @@ local function cleanPath(path)
end
function mtar.genHeader(fname,len) -- string number -- string -- generate a header for file *fname* when provided with file length *len*
return string.format("%s%s%s",cint(fname:len(),2),fname,cint(len,2))
return string.format("%s%s%s", string.pack(">I2",fname:len()), fname, string.pack(">I2",len))
end
function mtar.iter(stream) -- table -- function -- Given buffer *stream*, returns an iterator suitable for use with *for* that returns, for each iteration, the file name, a function to read from the file, and the length of the file.
@ -46,12 +27,12 @@ function mtar.iter(stream) -- table -- function -- Given buffer *stream*, return
while remain > 0 do
remain=remain-#stream:read(math.min(remain,2048))
end
local nlen = toint(stream:read(2) or "\0\0")
local nlen = string.unpack(">I2", stream:read(2) or "\0\0")
if nlen == 0 then
return
end
local name = cleanPath(stream:read(nlen))
local fsize = toint(stream:read(2))
local fsize = string.unpack(">I2", stream:read(2))
remain = fsize
return name, read, fsize
end