libs/web: fix luci.http.write_json() to properly encode control chars in strings

diff --git a/libs/web/luasrc/http.lua b/libs/web/luasrc/http.lua
index 18112507ce3565b6e7643ab8060fa61636282203..c53307a5a1eb4e2b3d72fabc6f2e0379c833eabd 100644 (file)
--- a/libs/web/luasrc/http.lua
+++ b/libs/web/luasrc/http.lua
@@ -4,9 +4,6 @@ LuCI - HTTP-Interaction
 Description:
 HTTP-Header manipulator and form variable preprocessor
 
-FileId:
-$Id$
-
 License:
 Copyright 2008 Steven Barth <steven@midlink.org>
 
@@ -334,12 +331,14 @@ function write_json(x)
                end
        elseif type(x) == "number" or type(x) == "boolean" then
                if (x ~= x) then
-                       -- NaN is the only value that doesn't equal to itself.   
+                       -- NaN is the only value that doesn't equal to itself.
                        write("Number.NaN")
                else
                        write(tostring(x))
                end
        else
-               write("%q" % tostring(x))
+               write('"%s"' % tostring(x):gsub('["%z\1-\31]', function(c)
+                       return '\\u%04x' % c:byte(1)
+               end))
        end
 end