diff options
author | chai <chaifix@163.com> | 2021-11-15 13:53:59 +0800 |
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committer | chai <chaifix@163.com> | 2021-11-15 13:53:59 +0800 |
commit | 942a030afd348ab2e02eac8054b43e3c3a72ea48 (patch) | |
tree | a13459f39a3d2f1b533fbd1b5ab523d7a621f673 /Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua | |
parent | e307051a56a54c27f10438fd2025edf61d0dfeed (diff) |
*rename
Diffstat (limited to 'Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua')
-rw-r--r-- | Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua b/Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua new file mode 100644 index 0000000..575c5a7 --- /dev/null +++ b/Data/BuiltIn/Libraries/lua-addons/addons/libs/ltn12.lua @@ -0,0 +1,309 @@ +----------------------------------------------------------------------------- +-- LTN12 - Filters, sources, sinks and pumps. +-- LuaSocket toolkit. +-- Author: Diego Nehab +----------------------------------------------------------------------------- + +----------------------------------------------------------------------------- +-- Declare module +----------------------------------------------------------------------------- +local string = require("string") +local table = require("table") +local unpack = unpack or table.unpack +local base = _G +local _M = {} +if module then -- heuristic for exporting a global package table + ltn12 = _M +end +local filter,source,sink,pump = {},{},{},{} + +_M.filter = filter +_M.source = source +_M.sink = sink +_M.pump = pump + +local unpack = unpack or table.unpack +local select = base.select + +-- 2048 seems to be better in windows... +_M.BLOCKSIZE = 2048 +_M._VERSION = "LTN12 1.0.3" + +----------------------------------------------------------------------------- +-- Filter stuff +----------------------------------------------------------------------------- +-- returns a high level filter that cycles a low-level filter +function filter.cycle(low, ctx, extra) + base.assert(low) + return function(chunk) + local ret + ret, ctx = low(ctx, chunk, extra) + return ret + end +end + +-- chains a bunch of filters together +-- (thanks to Wim Couwenberg) +function filter.chain(...) + local arg = {...} + local n = base.select('#',...) + local top, index = 1, 1 + local retry = "" + return function(chunk) + retry = chunk and retry + while true do + if index == top then + chunk = arg[index](chunk) + if chunk == "" or top == n then return chunk + elseif chunk then index = index + 1 + else + top = top+1 + index = top + end + else + chunk = arg[index](chunk or "") + if chunk == "" then + index = index - 1 + chunk = retry + elseif chunk then + if index == n then return chunk + else index = index + 1 end + else base.error("filter returned inappropriate nil") end + end + end + end +end + +----------------------------------------------------------------------------- +-- Source stuff +----------------------------------------------------------------------------- +-- create an empty source +local function empty() + return nil +end + +function source.empty() + return empty +end + +-- returns a source that just outputs an error +function source.error(err) + return function() + return nil, err + end +end + +-- creates a file source +function source.file(handle, io_err) + if handle then + return function() + local chunk = handle:read(_M.BLOCKSIZE) + if not chunk then handle:close() end + return chunk + end + else return source.error(io_err or "unable to open file") end +end + +-- turns a fancy source into a simple source +function source.simplify(src) + base.assert(src) + return function() + local chunk, err_or_new = src() + src = err_or_new or src + if not chunk then return nil, err_or_new + else return chunk end + end +end + +-- creates string source +function source.string(s) + if s then + local i = 1 + return function() + local chunk = string.sub(s, i, i+_M.BLOCKSIZE-1) + i = i + _M.BLOCKSIZE + if chunk ~= "" then return chunk + else return nil end + end + else return source.empty() end +end + +-- creates rewindable source +function source.rewind(src) + base.assert(src) + local t = {} + return function(chunk) + if not chunk then + chunk = table.remove(t) + if not chunk then return src() + else return chunk end + else + table.insert(t, chunk) + end + end +end + +-- chains a source with one or several filter(s) +function source.chain(src, f, ...) + if ... then f=filter.chain(f, ...) end + base.assert(src and f) + local last_in, last_out = "", "" + local state = "feeding" + local err + return function() + if not last_out then + base.error('source is empty!', 2) + end + while true do + if state == "feeding" then + last_in, err = src() + if err then return nil, err end + last_out = f(last_in) + if not last_out then + if last_in then + base.error('filter returned inappropriate nil') + else + return nil + end + elseif last_out ~= "" then + state = "eating" + if last_in then last_in = "" end + return last_out + end + else + last_out = f(last_in) + if last_out == "" then + if last_in == "" then + state = "feeding" + else + base.error('filter returned ""') + end + elseif not last_out then + if last_in then + base.error('filter returned inappropriate nil') + else + return nil + end + else + return last_out + end + end + end + end +end + +-- creates a source that produces contents of several sources, one after the +-- other, as if they were concatenated +-- (thanks to Wim Couwenberg) +function source.cat(...) + local arg = {...} + local src = table.remove(arg, 1) + return function() + while src do + local chunk, err = src() + if chunk then return chunk end + if err then return nil, err end + src = table.remove(arg, 1) + end + end +end + +----------------------------------------------------------------------------- +-- Sink stuff +----------------------------------------------------------------------------- +-- creates a sink that stores into a table +function sink.table(t) + t = t or {} + local f = function(chunk, err) + if chunk then table.insert(t, chunk) end + return 1 + end + return f, t +end + +-- turns a fancy sink into a simple sink +function sink.simplify(snk) + base.assert(snk) + return function(chunk, err) + local ret, err_or_new = snk(chunk, err) + if not ret then return nil, err_or_new end + snk = err_or_new or snk + return 1 + end +end + +-- creates a file sink +function sink.file(handle, io_err) + if handle then + return function(chunk, err) + if not chunk then + handle:close() + return 1 + else return handle:write(chunk) end + end + else return sink.error(io_err or "unable to open file") end +end + +-- creates a sink that discards data +local function null() + return 1 +end + +function sink.null() + return null +end + +-- creates a sink that just returns an error +function sink.error(err) + return function() + return nil, err + end +end + +-- chains a sink with one or several filter(s) +function sink.chain(f, snk, ...) + if ... then + local args = { f, snk, ... } + snk = table.remove(args, #args) + f = filter.chain(unpack(args)) + end + base.assert(f and snk) + return function(chunk, err) + if chunk ~= "" then + local filtered = f(chunk) + local done = chunk and "" + while true do + local ret, snkerr = snk(filtered, err) + if not ret then return nil, snkerr end + if filtered == done then return 1 end + filtered = f(done) + end + else return 1 end + end +end + +----------------------------------------------------------------------------- +-- Pump stuff +----------------------------------------------------------------------------- +-- pumps one chunk from the source to the sink +function pump.step(src, snk) + local chunk, src_err = src() + local ret, snk_err = snk(chunk, src_err) + if chunk and ret then return 1 + else return nil, src_err or snk_err end +end + +-- pumps all data from a source to a sink, using a step function +function pump.all(src, snk, step) + base.assert(src and snk) + step = step or pump.step + while true do + local ret, err = step(src, snk) + if not ret then + if err then return nil, err + else return 1 end + end + end +end + +return _M |