Integration with Alsa HookPlugin is now working.

11 files changed, 468 insertions, 89 deletions

diff --git a/conf.d/project/alsa.d/asoundrc.sample b/conf.d/project/alsa.d/asoundrc.sample
new file mode 100644
index 0000000..b208a09
--- /dev/null
+++ b/conf.d/project/alsa.d/asoundrc.sample
@@ -0,0 +1,146 @@
+# 
+# Author: Fulup Ar Foll
+# Object: PCM hook type 
+#
+# Test  :  Note: Jabra_USB=hw:v1340
+#  Check SoundCard  speaker-test -Dhw:v1340 -c2 -twav
+#  Check MixerPCM   speaker-test -DMyMixerPCM -c2 -twav 
+#  Check HookPCM    speaker-test -DMyNavigationHook -c2 -twav 
+#  Check NavPCM     speaker-test -DMyNavPCM -c2 -twav
+#  MultiMedia aplay -DDMyNavPCM /usr/share/sounds/alsa/test.wav
+#
+# Bug/Feature: when softvol control is initialised from plugin and not
+#    from AGL binding. At 1st run ctl has invalid TLV and cannot be
+#    use. Bypass Solution: 
+#     * start audio-binder before playing sound (binding create control before softvol plugin)
+#     * run a dummy aplay -DMyNavPCM "" to get a clean control
+#
+# References: https://www.spinics.net/lists/alsa-devel/msg54235.html
+# --------------------------------------------------------------------
+
+# Mixer PCM allow to play multiple stream simultaneously
+# ------------------------------------------------------
+pcm.MyMixerPCM { 
+    type dmix 
+    ipc_key 1024
+    ipc_key_add_uid false
+    ipc_perm 0666   # mixing for all users
+
+    # Define target effective sound card (cannot be a plugin)
+    slave { 
+        pcm "hw:v1340"  #Jabra Solmate 
+        period_time 0 
+        period_size 1024 
+        buffer_size 8192
+        rate 44100
+    }
+
+    # DMIX can only map two channels
+    bindings { 
+        0 0 
+        1 1 
+    } 
+} 
+
+# Define a Hook_type with a private sharelib
+# -------------------------------------------
+pcm_hook_type.MyHookPlugin {
+    install "AlsaInstallHook" 
+    lib "/home/fulup/Workspace/AGL-AppFW/audio-bindings-dev/build/Alsa-Plugin/Alsa-Policy-Hook/policy_hook_cb.so"
+}
+
+
+# Define a HookedPCM that point to Hook_type sharelib
+# ----------------------------------------------------
+pcm.MyNavigationHook {
+    type hooks
+    slave.pcm "MyMixerPCM"
+    # Defined used hook sharelib and provide arguments/config to install func
+    hooks.0 {
+        type "MyHookPlugin"
+        hook_args {
+            verbose true # print few log messages (default false);
+
+            # Every Call should return OK in order PCM to open (default timeout 100ms)
+            uri   "ws://localhost:1234/api?token='audio-agent-token'"
+            request {
+                # Request autorisation to write on navigation 
+                RequestNavigation {
+                    api    "control"
+                    verb   "dispatch"
+	            query  "{'target':'navigation', 'args':{'device':'Jabra SOLEMATE v1.34.0'}}"
+                } 
+            }
+            # map event reception to self generated signal
+            event {
+                pause  30
+                resume 31
+                stop   3
+            }
+        }
+    }
+}
+
+# If hardware does not support mixer emulate it with softvol
+# -----------------------------------------------------------
+pcm.MyMultimediaPCM {
+    type        softvol
+
+    # Point Slave on HOOK for policies control
+    slave.pcm   "MyNavigationHook"
+
+    # resolution=HAL(valMax+1) (default=256)
+    resolution 256
+
+    # name should match with HAL but do not set card=xx
+    control.name    "Playback Navigation"
+
+    # Make this plugin visible from aplay -L
+    hint {
+      show on
+      description "Navigation SolftVol PCM"
+    }    
+}
+
+# If hardware does not support mixer emulate it with softvol
+# -----------------------------------------------------------
+pcm.MyNavPCM {
+    type        softvol
+
+    # Point Slave on HOOK for policies control
+    slave.pcm   "MyNavigationHook"
+
+    # resolution=HAL(valMax+1) (default=256)
+    resolution 256
+
+    # name should match with HAL but do not set card=xx
+    control.name    "Playback Navigation"
+
+    # Make this plugin visible from aplay -L
+    hint {
+      show on
+      description "Navigation SolftVol PCM"
+    }    
+}
+
+# If hardware does not support mixer emulate it with softvol
+# -----------------------------------------------------------
+pcm.MyAlarmPCM {
+    type        softvol
+
+    # Point Slave on HOOK for policies control
+    slave.pcm   "MyNavigationHook"
+
+    # resolution=HAL(valMax+1) (default=256)
+    resolution 256
+
+    # name should match with HAL but do not set card=xx
+    control.name    "Playback Navigation"
+
+    # Make this plugin visible from aplay -L
+    hint {
+      show on
+      description "Navigation SolftVol PCM"
+    }    
+}
+
diff --git a/conf.d/project/alsa.d/ucm.sample/HDA Intel PCH.conf b/conf.d/project/alsa.d/ucm.sample/HDA Intel PCH.conf
new file mode 100644
index 0000000..f6608a0
--- /dev/null
+++ b/conf.d/project/alsa.d/ucm.sample/HDA Intel PCH.conf
@@ -0,0 +1,6 @@
+Comment "Leon internal card"
+
+SectionUseCase."HiFi" {
+	File "HiFi.conf"
+	Comment "Default"
+}
diff --git a/conf.d/project/alsa.d/ucm.sample/HiFi.conf b/conf.d/project/alsa.d/ucm.sample/HiFi.conf
new file mode 100644
index 0000000..9a53c8c
--- /dev/null
+++ b/conf.d/project/alsa.d/ucm.sample/HiFi.conf
@@ -0,0 +1,84 @@
+SectionVerb {
+	EnableSequence [
+		cdev "hw:PCH"
+
+		cset "name='Master Playback Switch' on"
+		cset "name='Headphone Playback Switch' off"
+		cset "name='Speaker Playback Switch' on"
+
+		cset "name='Capture Switch' on"
+		cset "name='Capture Volume' 39"
+		cset "name='Mic Boost Volume' 2"
+		cset "name='Internal Mic Boost Volume' 0"
+		#cset "name='Capture Source' 0"
+	]
+	DisableSequence [
+	]
+	Value {
+                TQ "Music"
+		OutputDspName "speaker_eq"
+                PlaybackPCM "hw:PCH,0"
+	}
+}
+
+SectionDevice."Headphone".0 {
+	Value {
+		JackName "Headphone Jack"
+		OutputDspName "Jheadphone"
+	}
+	EnableSequence [
+		cdev "hw:PCH"
+
+		cset "name='Speaker Playback Switch' off"
+		cset "name='Headphone Playback Switch' on"
+	]
+	DisableSequence [
+		cdev "hw:PCH"
+
+		cset "name='Headphone Playback Switch' off"
+		cset "name='Speaker Playback Switch' on"
+	]
+}
+
+SectionDevice."Mic".0 {
+	Value {
+		JackName "Mic Jack"
+	}
+	EnableSequence [
+		cdev "hw:PCH"
+
+		#cset "name='Capture Source' 1"
+	]
+	DisableSequence [
+		cdev "hw:PCH"
+
+		cset "name='Capture Source' 0"
+	]
+}
+
+SectionModifier."RecordMedia".0 {
+        SupportedDevice [
+                "Headphone"
+        ]
+        EnableSequence [
+                cdev "hw:PCH"
+        ]
+
+        DisableSequence [
+                cdev "hw:PCH"
+        ]
+
+        TransitionSequence."ToModifierName" [
+                cdev "hw:PCH"
+        ]
+
+        # Optional TQ and ALSA PCMs
+        Value {
+                TQ Voice
+                CapturePCM "hw:1"
+                PlaybackVolume "name='Master Playback Volume',index=2"
+                PlaybackSwitch "name='Master Playback Switch',index=2"
+        }
+
+}
+
diff --git a/conf.d/project/alsa.d/ucm.sample/README b/conf.d/project/alsa.d/ucm.sample/README
new file mode 100644
index 0000000..e7f08ae
--- /dev/null
+++ b/conf.d/project/alsa.d/ucm.sample/README
@@ -0,0 +1,2 @@
+Should match sound card name ex: "HDA Intel PCH"
+cp -r . /usr/share/alsa/ucm
diff --git a/conf.d/project/config.d/onload-audio-control.json b/conf.d/project/config.d/onload-audio-control.json
index 7180bd5..77a8fce 100644
--- a/conf.d/project/config.d/onload-audio-control.json
+++ b/conf.d/project/config.d/onload-audio-control.json
@@ -9,7 +9,7 @@
             "label": "onload-default",
             "info": "onload initialisation config",
             "plugin": {
-                "label" : "MyPlug",
+                "label" : "_MyPlug",
                 "sharelib": "ctl-audio-plugin-sample.ctlso",
                 "lua2c": ["Lua2cHelloWorld1", "Lua2cHelloWorld2"]
             },
@@ -28,11 +28,11 @@
                     "info": "Assert AlsaCore Presence",   
                     "api": "alsacore",
                     "verb": "ping",
-                    "args": "test"
+                    "args": {"data": "none"}
                 }, {
                     "label": "onload-hal-lua",
                     "info": "Load avaliable HALs",
-                    "lua": "Audio_Init_Hal"
+                    "lua": "_Alsa_Get_Hal"
                 }
             ]
         }],
@@ -43,20 +43,20 @@
                     "actions": {
                             "label": "multimedia-control-lua",
                             "info": "Call Lua Script function Test_Lua_Engin",   
-                            "lua": "Audio_Set_Multimedia"
+                            "lua": "_Audio_Set_Multimedia"
                         }
                 }, {
                     "label": "navigation",
                     "actions": {
                             "label": "navigation-control-lua",
                             "info": "Call Lua Script to set Navigation",   
-                            "lua": "Audio_Set_Navigation"
+                            "lua": "_Audio_Set_Navigation"
                         }
                 }, {
                     "label": "emergency",
                     "actions": {
                             "label": "emergency-control-ucm",
-                            "lua": "Audio_Set_Emergency"
+                            "lua": "_Audio_Set_Emergency"
                         }
                 }, {
                     "label": "multi-step-sample",
@@ -79,7 +79,7 @@
                         }, {
                             "label": "navigation-control-lua",
                             "info": "Call Lua Script to set Navigation",   
-                            "lua": "Audio_Set_Navigation"
+                            "lua": "_Audio_Set_Navigation"
                         }]
                 }
             ],
diff --git a/conf.d/project/lua.d/doscript-helloworld.lua b/conf.d/project/lua.d/doscript-helloworld.lua
index 64bc94a..a06c3db 100644
--- a/conf.d/project/lua.d/doscript-helloworld.lua
+++ b/conf.d/project/lua.d/doscript-helloworld.lua
@@ -21,7 +21,7 @@
 
 --]]
 
-function helloworld (request, query) 
+local function helloworld (request, query) 
 
     AFB:notice ("LUA HelloWorld: Simple test  query=%s", query);
 
diff --git a/conf.d/project/lua.d/onload-audio-0utils.lua b/conf.d/project/lua.d/onload-audio-0utils.lua
new file mode 100644
index 0000000..b8ecd7e
--- /dev/null
+++ b/conf.d/project/lua.d/onload-audio-0utils.lua
@@ -0,0 +1,86 @@
+--[[
+  Copyright (C) 2016 "IoT.bzh"
+  Author Fulup Ar Foll <fulup@iot.bzh>
+ 
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+ 
+    http://www.apache.org/licenses/LICENSE-2.0
+ 
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+  Note: this file should be called before any other to assert declare function
+  is loaded before anything else.
+
+  References:
+    http://lua-users.org/wiki/DetectingUndefinedVariables
+  
+--]]
+
+
+--===================================================
+--=  Niklas Frykholm 
+-- basically if user tries to create global variable
+-- the system will not let them!!
+-- call GLOBAL_lock(_G)
+--
+--===================================================
+function GLOBAL_lock(t)
+  local mt = getmetatable(t) or {}
+  mt.__newindex = lock_new_index
+  setmetatable(t, mt)
+end
+
+--===================================================
+-- call GLOBAL_unlock(_G)
+-- to change things back to normal.
+--===================================================
+function GLOBAL_unlock(t)
+  local mt = getmetatable(t) or {}
+  mt.__newindex = unlock_new_index
+  setmetatable(t, mt)
+end
+
+function lock_new_index(t, k, v)
+  if (string.sub(k,1,1) ~= "_") then
+    GLOBAL_unlock(_G)
+    error("GLOBALS are locked -- " .. k ..
+          " must be declared local or prefix with '_' for globals.", 2)
+  else
+    rawset(t, k, v)
+  end
+end
+
+function unlock_new_index(t, k, v)
+  rawset(t, k, v)
+end
+
+-- return serialised version of printable table
+function Dump_Table(o)
+   if type(o) == 'table' then
+      local s = '{ '
+      for k,v in pairs(o) do
+         if type(k) ~= 'number' then k = '"'..k..'"' end
+         s = s .. '['..k..'] = ' .. Dump_Table(v) .. ','
+      end
+      return s .. '} '
+   else
+      return tostring(o)
+   end
+end
+
+
+-- simulate C prinf function
+printf = function(s,...)
+    io.write(s:format(...))
+    io.write("\n")
+    return
+end
+
+-- lock global variable
+GLOBAL_lock(_G)
diff --git a/conf.d/project/lua.d/onload-audio-controls.lua b/conf.d/project/lua.d/onload-audio-controls.lua
index 4849632..24c4f71 100644
--- a/conf.d/project/lua.d/onload-audio-controls.lua
+++ b/conf.d/project/lua.d/onload-audio-controls.lua
@@ -18,54 +18,145 @@
   Provide sample policy function for AGL Advance Audio Agent
 --]]
 
-function Audio_Init_CB (status, result, context)
-    print ("--inlua:Audio_Init_CB-- result=", Dump_Table(result))
-    print ("--inlua:Audio_Init_CB-- context=", Dump_Table(context))
- 
-    AFB:notice("Audio_Init_Hal_CB result='%s' context='%s'", result, context)
+-- Global HAL registry
+_Audio_Hal_Registry={}
+
+-- Callback when receiving HAL registry
+function _Alsa_Get_Hal_CB (error, result, context)
+   -- Initialise an empty table
+   local registry={}
+
+    -- Only process when response is valid
+    if (error) then 
+         AFB_ErrOr ("[Audio_Init_CB] ErrOr result=%s", result)
+        return
+    end
+
+    -- Extract response from result
+    local response=result["response"]
+
+    -- Index HAL Bindings APIs by shortname
+    for key,value in pairs(response) do
+        registry[value["shortname"]]=value["api"]
+    end
+    
+    -- store Exiting HAL for further use
+    printf ("-- [Audio_Init_CB] -- Audio_register_Hal=%s", Dump_Table(registry))
+    _Audio_Hal_Registry=registry
       
 end
 
 -- Function call at binding load time
-function Audio_Init_Hal(args, query)
+function _Alsa_Get_Hal(args)
 
-   local nested = {
-    ["next1"]=1234,
-    ["next2"]="nested",
-    ["next3"]=9999,
-   }
-   local context = {
-    ["arg1"]=1234,
-    ["arg2"]=nested,
-    ["arg3"]=5678,
-   }
+    printf ("[-- Audio_Get_Hal --] args=%s", Dump_Table(argsT))
+    
+    -- Query AlsaCore for Active HALs (no query, no context)
+    AFB:service ('alsacore', 'hallist', {}, "_Alsa_Get_Hal_CB", {})
+ 
+end
 
-    print ("--inlua:Audio_Init-- response=", Dump_Table(responseT))
+-- In sample configuration Query/Args parsing is common to all audio control
+local function Audio_Parse_Request (source, args, query)
 
-    print("myplug=",  Dump_Table(MyPlug));
+    local apihal={}
 
-    -- This routine is defined in C sample plugin
-    local status=MyPlug:Lua2cHelloWorld1(nested)
-    
-    -- query asynchronously loaded HAL
-    AFB:service ('alsacore', 'hallist', {}, "Audio_Init_CB", context)
- 
+    -- In this test we expect targeted device to be given from query (could come for args as well)
+    if (query == nil ) then
+        AFB:error ("--LUA:Audio_Set_Navigation query should contain and args with targeted apihal|device")
+        return  -- refuse control
+    end
+
+    -- Alsa Hook plugin asound sample config provides target sound card by name
+    if (query["device"] ~= nil) then 
+        apihal=_Audio_Hal_Registry[query["device"]]
+    end
+
+    -- HTML5 test page provides directly HAL api.
+    if (query["apihal"] ~= nil) then
+       apihal= query["apihal"]
+    end
+
+    -- if requested HAL is not found then deny the control
+    if (apihal == nil) then
+        AFB:error ("--LUA:Audio_Set_Navigation No Active HAL Found")
+        return  -- refuse control
+    end
+
+    -- return api or nil when not found
+    return apihal
 end
 
-function Audio_Set_Navigation(args, query)
+-- Set Navigation lower sound when play
+function _Audio_Set_Navigation(source, args, query)
+
+    -- in strict mode every variables should be declared
+    local err=0
+    local ctlhal={}
+    local response={}
+    local apihal={}
+
+    AFB:notice ("LUA:Audio_Set_Use_Case source=%d args=%s query=%s", source, args, query);
+   
+    -- Parse Query/Args and if HAL not found then refuse access
+    apihal= Audio_Parse_Request (source, args, query)
+    if (apihal == nil) then return 1 end
+
 
-    AFB:notice ("LUA:Audio_Set_Use_Case args=%s query=%s", args, query);
+    -- if source < 0 then Alsa HookPlugin is closing PCM
+    if (source < 0) then
+        -- Ramp Up Multimedia channel synchronously
+        ctlhal={['label']='Master_Playback_Volume', ['val']=100}
+        err, response= AFB:servsync (apihal, 'ctlset',ctlhal)
+    else
+        -- Ramp Down Multimedia channel synchronously
+        ctlhal={['label']='Master_Playback_Volume', ['val']=50}
+        err, response= AFB:servsync (apihal, 'ctlset',ctlhal)
+    end
 
-    -- synchronous call to alsacore service
-    local error,data= AFB:callsync ('alsacore', 'ping', {})  
-    if (error) then
-      AFB:error ("LUA:Audio_Set_Use_Case FAIL args=%s", args)
-    else 
-      AFB:notice ("--LUA:Audio_Set_Use_Case DONE args=%s response=%s", args, data["response"])
+    if (err) then 
+        AFB:error("--LUA:Audio_Set_Navigation halapi=%s refuse ctl=%s", apihal, ctlhal)
+        return 1 -- control refused
     end
 
-    -- return OK
-    return 0
+
+    return 0 -- control accepted
 end
 
 
+-- Select Multimedia mode
+function _Audio_Set_Multimedia (source, args, query)
+
+    -- in strict mode every variables should be declared
+    local err=0
+    local ctlhal={}
+    local response={}
+    local apihal={}
+
+    AFB:notice ("LUA:Audio_Set_Use_Case source=%d args=%s query=%s", source, args, query);
+   
+    -- Parse Query/Args and if HAL not found then refuse access
+    apihal= Audio_Parse_Request (source, args, query)
+    if (apihal == nil) then return 1 end
+
+
+    -- if Mumtimedia control only increase volume on open
+    if (source >= 0) then
+        -- Ramp Down Multimedia channel synchronously
+        ctlhal={['label']='Master_Playback_Volume', ['val']=100}
+        err, response= AFB:servsync (apihal, 'ctlset',ctlhal)
+    end
+
+    if (err) then 
+        AFB:error("--LUA:Audio_Set_Navigation halapi=%s refuse ctl=%s", apihal, ctlhal)
+        return 1 -- control refused
+    end
+
+
+    return 0 -- control accepted
+end
+
+-- Select Emergency Mode
+function _Audio_Set_Emergency(source, args, query)
+    return 1 -- Always refuse in this test
+end
diff --git a/conf.d/project/lua.d/onload-audio-oncall.lua b/conf.d/project/lua.d/onload-audio-oncall.lua
index 08b25e5..23b538e 100644
--- a/conf.d/project/lua.d/onload-audio-oncall.lua
+++ b/conf.d/project/lua.d/onload-audio-oncall.lua
@@ -18,18 +18,18 @@
   Provide sample LUA routines to be used with AGL control "lua_docall" API
 --]]
 
--- global counter to keep track of calls
-count=0
+--global counter to keep track of calls
+_count=0
 
 -- Display receive arguments and echo them to caller
-function Simple_Echo_Args (request, args)
-    count=count+1
+function _Simple_Echo_Args (request, args)
+    _count=_count+1
     AFB:notice("LUA OnCall Echo Args count=%d args=%s", count, args)
 
     print ("--inlua-- args=", Dump_Table(args))
 
     local response={
-       ["count"]=count,
+       ["count"]=_count,
        ["args"]=args,
     }
 
@@ -37,7 +37,7 @@ function Simple_Echo_Args (request, args)
     AFB:success (request,  {["func"]="Simple_Echo_Args", ["ret1"]=5678, ["ret2"]="abcd"}) 
 end
 
-function Test_Async_CB (request, result, context)
+local function Test_Async_CB (request, result, context)
    response={
      ["result"]=result,
      ["context"]=context,
@@ -47,7 +47,7 @@ function Test_Async_CB (request, result, context)
    AFB:success (request, response)
 end
 
-function Test_Call_Async (request, args) 
+function _Test_Call_Async (request, args) 
    local context={
      ["value1"]="abcd",
      ["value2"]=1234
@@ -57,7 +57,7 @@ function Test_Call_Async (request, args)
    AFB:service("alsacore","ping", "Test_Async_CB", context)
 end
 
-function Test_Call_Sync (request, args) 
+function _Test_Call_Sync (request, args) 
 
     AFB:notice ("Test_Call_Sync args=%s", args)
     local err, response= AFB:service_sync ("alsacore","ping", args)
diff --git a/conf.d/project/lua.d/onload-audio-timer.lua b/conf.d/project/lua.d/onload-audio-timer.lua
index 5f25de7..db7a937 100644
--- a/conf.d/project/lua.d/onload-audio-timer.lua
+++ b/conf.d/project/lua.d/onload-audio-timer.lua
@@ -19,11 +19,10 @@
 --]]
 
 -- Create event on Lua script load
-print ("*** Create MyTestEvent ***")
-MyEventHandle= AFB:evtmake("MyTestEvent")
+local MyEventHandle=AFB:evtmake("MyTestEvent")
 
 -- Call count time every delay/ms 
-function Timer_Test_CB (timer, context) 
+local function Timer_Test_CB (timer, context) 
 
    local evtinfo= AFB:timerget(timer)
    print ("timer=", Dump_Table(evtinfo))
@@ -37,7 +36,7 @@ function Timer_Test_CB (timer, context)
 end
 
 -- sendback event depending on count and delay
-function Simple_Timer_Test (request, args)
+function _Simple_Timer_Test (request, args)
  
     local context = {
         ["info"]="My 1st private Event",
@@ -68,6 +67,3 @@ function Simple_Timer_Test (request, args)
 
     return 0
 end
-
-
-
diff --git a/conf.d/project/lua.d/onload-audio-utils.lua b/conf.d/project/lua.d/onload-audio-utils.lua
deleted file mode 100644
index 40ef8a3..0000000
--- a/conf.d/project/lua.d/onload-audio-utils.lua
+++ /dev/null
@@ -1,32 +0,0 @@
---[[
-  Copyright (C) 2016 "IoT.bzh"
-  Author Fulup Ar Foll <fulup@iot.bzh>
- 
-  Licensed under the Apache License, Version 2.0 (the "License");
-  you may not use this file except in compliance with the License.
-  You may obtain a copy of the License at
- 
-    http://www.apache.org/licenses/LICENSE-2.0
- 
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  See the License for the specific language governing permissions and
-  limitations under the License.
-  
---]]
-
-
--- return serialised version of printable table
-function Dump_Table(o)
-   if type(o) == 'table' then
-      local s = '{ '
-      for k,v in pairs(o) do
-         if type(k) ~= 'number' then k = '"'..k..'"' end
-         s = s .. '['..k..'] = ' .. Dump_Table(v) .. ','
-      end
-      return s .. '} '
-   else
-      return tostring(o)
-   end
-end