moth/cgi/cgi.lua

110 lines
2.2 KiB
Lua

#! /usr/bin/lua
local cgi = {}
cgi.POST_MAX = 512
local CL = tonumber(os.getenv("CONTENT_LENGTH")) or 0
function getc_post()
if (CL > 0) then
CL = CL - 1
return io.read(1)
else
return nil
end
end
local query = os.getenv("QUERY_STRING") or ""
local query_len = query:len()
local query_pos = 0
function getc_get()
if (query_pos < query_len) then
query_pos = query_pos + 1
return string.sub(query, query_pos, query_pos)
else
return nil
end
end
function cgi.http_error(code, name, info)
print(code .. " " .. name)
print("Allow: GET POST")
print("Content-type: text/html")
print()
print("<h1>" .. code .. " " .. name .. "</h1>")
print("<p>" .. info .. "</p>")
os.exit(0)
end
function cgi.init()
method = os.getenv("REQUEST_METHOD")
if (method == "POST") then
if (os.getenv("HTTP_CONTENT_TYPE") ~= "application/x-www-form-urlencoded") then
cgi.http_error(415, "Unsupported content-type", "You are sending me data in a format I can't process")
end
if (CL > cgi.POST_MAX) then
cgi.http_error(413, "Post Data Too Long", "You are sending me more data than I'm prepared to handle")
end
getc = getc_post
elseif (method == "GET") then
local query = os.getenv("QUERY_STRING") or ""
local query_pos = 0
local query_len = string.len(query)
if (query_len > cgi.POST_MAX) then
cgi.http_error(413, "Query Data Too Long", "You are sending me more data than I'm prepared to handle")
end
getc = getc_get
else
cgi.http_error(405, "Method not allowed", "I only do GET and POST.")
end
end
function cgi.read_hex()
local a = getc() or 0
local b = getc() or 0
return string.char(tonumber(a, 16)*16 + tonumber(b, 16))
end
function cgi.item()
local val = ""
while (true) do
local c = getc()
if ((c == nil) or (c == "=") or (c == "&")) then
return val
elseif (c == "%") then
c = read_hex()
elseif (c == "+") then
c = " "
end
val = val .. c
end
end
function cgi.fields()
local ret = {}
while (true) do
local k = cgi.item()
local v = cgi.item()
if (k == "") then
return ret
end
ret[k] = v
end
end
function cgi.escape(s)
s = string.gsub(s, "&", "&amp;")
s = string.gsub(s, "<", "&lt;")
s = string.gsub(s, ">", "&gt;")
return s
end
return cgi