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| author | Kim Alvefur <zash@zash.se> | 2015-10-06 18:03:04 +0200 |
|---|---|---|
| committer | Kim Alvefur <zash@zash.se> | 2015-10-06 18:03:04 +0200 |
| commit | 2efcb9f82f22b826e3903bb1e014e64570bbb3e5 (patch) | |
| tree | bdb51b87d13bdc653daa67c03a116279bf764adc /net | |
| parent | 5d941b553acfce45e531ac56fa15cda472e728fe (diff) | |
| download | prosody-2efcb9f82f22b826e3903bb1e014e64570bbb3e5.tar.gz prosody-2efcb9f82f22b826e3903bb1e014e64570bbb3e5.zip | |
net.websocket.frames: Pack and unpack 64bit ints without overflows (lua-bitop/bit32 are 32bit)
Diffstat (limited to 'net')
| -rw-r--r-- | net/websocket/frames.lua | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/net/websocket/frames.lua b/net/websocket/frames.lua index e8faab2b..8528ab99 100644 --- a/net/websocket/frames.lua +++ b/net/websocket/frames.lua @@ -30,8 +30,9 @@ end -- FIXME: this may lose precision local function read_uint64be(str, pos) local l1, l2, l3, l4, l5, l6, l7, l8 = s_byte(str, pos, pos+7); - return lshift(l1, 56) + lshift(l2, 48) + lshift(l3, 40) + lshift(l4, 32) - + lshift(l5, 24) + lshift(l6, 16) + lshift(l7, 8) + l8; + local h = lshift(l1, 24) + lshift(l2, 16) + lshift(l3, 8) + l4; + local l = lshift(l5, 24) + lshift(l6, 16) + lshift(l7, 8) + l8; + return h * 2^32 + l; end local function pack_uint16be(x) return s_char(rshift(x, 8), band(x, 0xFF)); @@ -40,8 +41,9 @@ local function get_byte(x, n) return band(rshift(x, n), 0xFF); end local function pack_uint64be(x) - return s_char(rshift(x, 56), get_byte(x, 48), get_byte(x, 40), get_byte(x, 32), - get_byte(x, 24), get_byte(x, 16), get_byte(x, 8), band(x, 0xFF)); + local h = band(x / 2^32, 2^32-1); + return s_char(get_byte(h, 24), get_byte(h, 16), get_byte(h, 8), band(h, 0xFF)); + get_byte(x, 24), get_byte(x, 16), get_byte(x, 8), band(x, 0xFF); end local function parse_frame_header(frame) |