aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorKim Alvefur <zash@zash.se>2019-07-22 01:58:57 +0200
committerKim Alvefur <zash@zash.se>2019-07-22 01:58:57 +0200
commit3dcfc5ee71761a90edbd32165725f38ffd323237 (patch)
tree0278d1d911935484dc9b2eae41b9d1490ff5ca82
parent42861396cd1eeb5a880691e9ee00a75836b2fddb (diff)
downloadprosody-3dcfc5ee71761a90edbd32165725f38ffd323237.tar.gz
prosody-3dcfc5ee71761a90edbd32165725f38ffd323237.zip
util.bitops: Library to find appropriate bitwise library (closes #1395)
-rw-r--r--net/websocket/frames.lua3
-rw-r--r--util/bit53.lua7
-rw-r--r--util/bitcompat.lua32
3 files changed, 40 insertions, 2 deletions
diff --git a/net/websocket/frames.lua b/net/websocket/frames.lua
index 86752109..5e17df07 100644
--- a/net/websocket/frames.lua
+++ b/net/websocket/frames.lua
@@ -9,8 +9,7 @@
local softreq = require "util.dependencies".softreq;
local random_bytes = require "util.random".bytes;
-local bit = assert(softreq"bit32" or softreq"bit",
- "No bit module found. See https://prosody.im/doc/depends#bitop");
+local bit = require "util.bitcompat";
local band = bit.band;
local bor = bit.bor;
local bxor = bit.bxor;
diff --git a/util/bit53.lua b/util/bit53.lua
new file mode 100644
index 00000000..4b5c2e9c
--- /dev/null
+++ b/util/bit53.lua
@@ -0,0 +1,7 @@
+-- Only the operators needed by net.websocket.frames are provided at this point
+return {
+ band = function (a, b) return a & b end;
+ bor = function (a, b) return a | b end;
+ bxor = function (a, b) return a ~ b end;
+};
+
diff --git a/util/bitcompat.lua b/util/bitcompat.lua
new file mode 100644
index 00000000..454181af
--- /dev/null
+++ b/util/bitcompat.lua
@@ -0,0 +1,32 @@
+-- Compatibility layer for bitwise operations
+
+-- First try the bit32 lib
+-- Lua 5.3 has it with compat enabled
+-- Lua 5.2 has it by default
+if _G.bit32 then
+ return _G.bit32;
+else
+ -- Lua 5.1 may have it as a standalone module that can be installed
+ local ok, bitop = pcall(require, "bit32")
+ if ok then
+ return bitop;
+ end
+end
+
+do
+ -- Lua 5.3 and 5.4 would be able to use native infix operators
+ local ok, bitop = pcall(require, "util.bit53")
+ if ok then
+ return bitop;
+ end
+end
+
+do
+ -- Lastly, try the LuaJIT bitop library
+ local ok, bitop = pcall(require, "bit")
+ if ok then
+ return bitop;
+ end
+end
+
+error "No bit module found. See https://prosody.im/doc/depends#bitop";