Software / code / prosody-modules
Changeset
910:c469a2b2d77d
mod_websocket: Avoid floating point division
The problem here was that Lua's integer conversion (rounding?) routines
behave differently on x86 vs. x86_64 (and even on those there can be
minor differenes). Usually the former does proper rounding,
while the later floors.
| author | Florian Zeitz <florob@babelmonkeys.de> |
|---|---|
| date | Fri, 15 Feb 2013 01:32:03 +0100 |
| parents | 909:ec4c6e8f277d |
| children | 911:46e807dff445 |
| files | mod_websocket/mod_websocket.lua |
| diffstat | 1 files changed, 4 insertions(+), 3 deletions(-) [+] |
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line diff
--- a/mod_websocket/mod_websocket.lua Wed Feb 13 21:03:45 2013 +0100 +++ b/mod_websocket/mod_websocket.lua Fri Feb 15 01:32:03 2013 +0100 @@ -19,6 +19,7 @@ if not bit then module:log("error", "No bit module found. Either LuaJIT 2, lua-bitop or Lua 5.2 is required"); end local band = bit.band; local bxor = bit.bxor; +local rshift = bit.rshift; local cross_domain = module:get_option("cross_domain_websocket"); if cross_domain then @@ -104,11 +105,11 @@ result = result .. string.char(length); elseif length <= 0xFFFF then -- 2-byte length result = result .. string.char(126); - result = result .. string.char(length/0x100) .. string.char(length%0x100); + result = result .. string.char(rshift(length, 8)) .. string.char(length%0x100); else -- 8-byte length result = result .. string.char(127); for i = 7, 0, -1 do - result = result .. string.char(( length / (2^(8*i)) ) % 0x100); + result = result .. string.char(rshift(length, 8*i) % 0x100); end end @@ -139,7 +140,7 @@ end local function websocket_close(code, message) - local data = string.char(code/0x100) .. string.char(code%0x100) .. message; + local data = string.char(rshift(code, 8)) .. string.char(code%0x100) .. message; conn:write(build_frame({opcode = 0x8, FIN = true, data = data})); conn:close(); end
