1 files changed, 295 insertions, 0 deletions
diff --git a/libs/luci-lib-httpclient/luasrc/httpclient/receiver.lua b/libs/luci-lib-httpclient/luasrc/httpclient/receiver.lua
new file mode 100644
index 0000000000..4f08e93fe0
--- /dev/null
+++ b/libs/luci-lib-httpclient/luasrc/httpclient/receiver.lua
@@ -0,0 +1,295 @@
+--[[
+LuCI - Lua Development Framework 
+
+Copyright 2009 Steven Barth <steven@midlink.org>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+]]--
+
+require "nixio.util"
+local nixio = require "nixio"
+local httpc = require "luci.httpclient"
+local ltn12 = require "luci.ltn12"
+
+local print, tonumber, require, unpack = print, tonumber, require, unpack
+
+module "luci.httpclient.receiver"
+
+local function prepare_fd(target)
+	-- Open fd for appending
+	local oflags = nixio.open_flags("wronly", "creat")
+	local file, code, msg = nixio.open(target, oflags)
+	if not file then
+		return file, code, msg
+	end
+	
+	-- Acquire lock
+	local stat, code, msg = file:lock("tlock")
+	if not stat then
+		return stat, code, msg
+	end
+	
+	file:seek(0, "end") 
+	
+	return file
+end
+
+local function splice_async(sock, pipeout, pipein, file, cb)
+	local ssize = 65536
+	local smode = nixio.splice_flags("move", "more", "nonblock")
+
+	-- Set pipe non-blocking otherwise we might end in a deadlock
+	local stat, code, msg = pipein:setblocking(false)
+	if stat then
+		stat, code, msg = pipeout:setblocking(false)
+	end
+	if not stat then
+		return stat, code, msg
+	end
+	
+	
+	local pollsock = {
+		{fd=sock, events=nixio.poll_flags("in")}
+	}
+	
+	local pollfile = {
+		{fd=file, events=nixio.poll_flags("out")}
+	}
+	
+	local done
+	local active -- Older splice implementations sometimes don't detect EOS
+	
+	repeat
+		active = false
+		
+		-- Socket -> Pipe
+		repeat
+			nixio.poll(pollsock, 15000)
+		
+			stat, code, msg = nixio.splice(sock, pipeout, ssize, smode)
+			if stat == nil then
+				return stat, code, msg
+			elseif stat == 0 then
+				done = true
+				break
+			elseif stat then
+				active = true
+			end
+		until stat == false
+		
+		-- Pipe -> File
+		repeat
+			nixio.poll(pollfile, 15000)
+		
+			stat, code, msg = nixio.splice(pipein, file, ssize, smode)
+			if stat == nil then
+				return stat, code, msg
+			elseif stat then
+				active = true
+			end
+		until stat == false
+		
+		if cb then
+			cb(file)
+		end
+		
+		if not active then
+			-- We did not splice any data, maybe EOS, fallback to default
+			return false
+		end
+	until done
+	
+	pipein:close()
+	pipeout:close()
+	sock:close()
+	file:close()
+	return true
+end
+
+local function splice_sync(sock, pipeout, pipein, file, cb)
+	local os = require "os"
+	local ssize = 65536
+	local smode = nixio.splice_flags("move", "more")
+	local stat
+	
+	-- This is probably the only forking http-client ;-)
+	local pid, code, msg = nixio.fork()
+	if not pid then
+		return pid, code, msg
+	elseif pid == 0 then
+		pipein:close()
+		file:close()
+
+		repeat
+			stat, code = nixio.splice(sock, pipeout, ssize, smode)
+		until not stat or stat == 0
+	
+		pipeout:close()
+		sock:close()
+		os.exit(stat or code)
+	else
+		pipeout:close()
+		sock:close()
+		
+		repeat
+			stat, code, msg = nixio.splice(pipein, file, ssize, smode)
+			if cb then
+				cb(file)
+			end
+		until not stat or stat == 0
+		
+		pipein:close()
+		file:close()
+		
+		if not stat then
+			nixio.kill(pid, 15)
+			nixio.wait(pid)
+			return stat, code, msg
+		else
+			pid, msg, code = nixio.wait(pid)
+			if msg == "exited" then
+				if code == 0 then
+					return true
+				else
+					return nil, code, nixio.strerror(code)
+				end
+			else
+				return nil, -0x11, "broken pump"
+			end
+		end
+	end
+end
+
+function request_to_file(uri, target, options, cbs)
+	options = options or {}
+	cbs = cbs or {}
+	options.headers = options.headers or {}
+	local hdr = options.headers
+	local file, code, msg
+	
+	if target then
+		file, code, msg = prepare_fd(target)
+		if not file then
+			return file, code, msg
+		end
+	
+		local off = file:tell()
+		
+		-- Set content range
+		if off > 0 then
+			hdr.Range = hdr.Range or ("bytes=" .. off .. "-")  
+		end
+	end
+	
+	local code, resp, buffer, sock = httpc.request_raw(uri, options)
+	if not code then
+		-- No success
+		if file then
+			file:close()
+		end
+		return code, resp, buffer
+	elseif hdr.Range and code ~= 206 then
+		-- We wanted a part but we got the while file
+		sock:close()
+		if file then
+			file:close()
+		end
+		return nil, -4, code, resp
+	elseif not hdr.Range and code ~= 200 then
+		-- We encountered an error
+		sock:close()
+		if file then
+			file:close()
+		end
+		return nil, -4, code, resp
+	end
+	
+	if cbs.on_header then
+		local stat = {cbs.on_header(file, code, resp)}
+		if stat[1] == false then
+			if file then
+				file:close()
+			end
+			sock:close()
+			return unpack(stat)
+		elseif stat[2] then
+			file = file and stat[2]
+		end
+	end
+	
+	if not file then
+		return nil, -5, "no target given"
+	end
+
+	local chunked = resp.headers["Transfer-Encoding"] == "chunked"
+	local stat
+
+	-- Write the buffer to file
+	file:writeall(buffer)
+	
+	repeat
+		if not options.splice or not sock:is_socket() or chunked then
+			break
+		end
+		
+		-- This is a plain TCP socket and there is no encoding so we can splice
+	
+		local pipein, pipeout, msg = nixio.pipe()
+		if not pipein then
+			sock:close()
+			file:close()
+			return pipein, pipeout, msg
+		end
+		
+		
+		-- Adjust splice values
+		local ssize = 65536
+		local smode = nixio.splice_flags("move", "more")
+		
+		-- Splicing 512 bytes should never block on a fresh pipe
+		local stat, code, msg = nixio.splice(sock, pipeout, 512, smode)
+		if stat == nil then
+			break
+		end
+		
+		-- Now do the real splicing
+		local cb = cbs.on_write
+		if options.splice == "asynchronous" then
+			stat, code, msg = splice_async(sock, pipeout, pipein, file, cb)
+		elseif options.splice == "synchronous" then
+			stat, code, msg = splice_sync(sock, pipeout, pipein, file, cb)
+		else
+			break
+		end
+		
+		if stat == false then
+			break
+		end
+
+		return stat, code, msg
+	until true
+	
+	local src = chunked and httpc.chunksource(sock) or sock:blocksource()
+	local snk = file:sink()
+	
+	if cbs.on_write then
+		src = ltn12.source.chain(src, function(chunk)
+			cbs.on_write(file)
+			return chunk
+		end)
+	end
+	
+	-- Fallback to read/write
+	stat, code, msg = ltn12.pump.all(src, snk)
+
+	file:close()
+	sock:close()
+	return stat and true, code, msg
+end
+