libs/core: Add recursion detection to dumptable, serialize_data

[project/luci.git] / libs / core / luasrc / util.lua

diff --git a/libs/core/luasrc/util.lua b/libs/core/luasrc/util.lua
index cc15d3a..14bd1e7 100644 (file)
--- a/libs/core/luasrc/util.lua
+++ b/libs/core/luasrc/util.lua
@@ -185,12 +185,19 @@ end
 -- @param t    Table value to dump
 -- @param i    Number of tabs to prepend to each line
 -- @return     Always nil
-function dumptable(t, i)
+function dumptable(t, i, seen)
        i = i or 0
+       seen = seen or setmetatable({}, {__mode="k"})
+       
        for k,v in pairs(t) do
-               print(string.rep("\t", i) .. tostring(k), tostring(v))
+               perror(string.rep("\t", i) .. tostring(k), tostring(v))
                if type(v) == "table" then
-                       dumptable(v, i+1)
+                       if not seen[v] then
+                               seen[v] = true
+                               dumptable(v, i+1, seen)
+                       else
+                               perror(string.rep("\t", i) .. "*** RECURSION ***")
+                       end
                end
        end
 end
@@ -425,11 +432,14 @@ end
 
 
 -- Serialize the contents of a table value.
-function _serialize_table(t)
+function _serialize_table(t, seen)
+       assert(not seen[t], "Recursion detected.")
+       seen[t] = true
+       
        local data = ""
        for k, v in pairs(t) do
-               k = serialize_data(k)
-               v = serialize_data(v)
+               k = serialize_data(k, seen)
+               v = serialize_data(v, seen)
                data = data .. ( #data > 0 and ", " or "" ) ..
                        '[' .. k .. '] = ' .. v
        end
@@ -442,7 +452,9 @@ end
 -- @return             String value containing the serialized code
 -- @see                        restore_data
 -- @see                        get_bytecode
-function serialize_data(val)
+function serialize_data(val, seen)
+       seen = seen or setmetatable({}, {__mode="k"})
+       
        if val == nil then
                return "nil"
        elseif type(val) == "number" then
@@ -454,7 +466,7 @@ function serialize_data(val)
        elseif type(val) == "function" then
                return string.format("loadstring(%q)", get_bytecode(val))
        elseif type(val) == "table" then
-               return "{ " .. _serialize_table(val) .. " }"
+               return "{ " .. _serialize_table(val, seen) .. " }"
        else
                return '"[unhandled data type:' .. type(val) .. ']"'
        end