optimize: reimplemented the coroutine wrapper using the ffi api. (openresty#383)

Author: zhuizhuhaomeng

.travis.yml

@@ -53,7 +53,7 @@ services:
 
 before_install:
   - sudo luarocks install luacheck $LUACHECK_VER
-  - luacheck -q .
+  - luacheck --globals coroutine -q .
   - '! grep -n -P ''(?<=.{80}).+'' --color `find . -name ''*.lua''` || (echo "ERROR: Found Lua source lines exceeding 80 columns." > /dev/stderr; exit 1)'
   - '! grep -n -P ''\t+'' --color `find . -name ''*.lua''` || (echo "ERROR: Cannot use tabs." > /dev/stderr; exit 1)'
   - sudo cpanm --notest Test::Nginx IPC::Run > build.log 2>&1 || (cat build.log && exit 1)

lib/resty/core.lua

@@ -20,6 +20,7 @@ if subsystem == 'http' then
     require "resty.core.phase"
     require "resty.core.ndk"
     require "resty.core.socket"
+    require "resty.core.coroutine"
 end
 
 

lib/resty/core/coroutine.lua

@@ -0,0 +1,29 @@
+local base = require "resty.core.base"
+local get_request = base.get_request
+
+do
+    local keys = {'create', 'yield', 'resume', 'status', 'wrap'}
+    local errmsg = base.get_errmsg_ptr()
+    local get_raw_phase = ngx.get_raw_phase
+
+    for _, key in ipairs(keys) do
+        local std = coroutine['_' .. key]
+        local ours = coroutine['__' .. key]
+        coroutine[key] = function (...)
+            local r = get_request()
+            if r ~= nil then
+                local ctx = get_raw_phase(r, errmsg)
+                if ctx ~= 0x020 and ctx ~= 0x040 then
+                    return ours(...)
+                end
+            end
+            return std(...)
+        end
+    end
+
+    package.loaded.coroutine = coroutine
+end
+
+return {
+    version = base.version
+}

lib/resty/core/phase.lua

@@ -55,6 +55,16 @@ function ngx.get_phase()
 end
 
 
+function ngx.get_raw_phase(r)
+    local context = C.ngx_http_lua_ffi_get_phase(r, errmsg)
+    if context == FFI_ERROR then -- NGX_ERROR
+        error(errmsg, 2)
+    end
+
+    return context
+end
+
+
 return {
     version = base.version
 }