aboutsummaryrefslogtreecommitdiffstats
path: root/Controler-afb/ctl-lua.c
blob: 8b40e387e492a006eb5b7256ff086b7daaa9add6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
/*
 * 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.
 * ref: 
 *  http://www.troubleshooters.com/codecorn/lua/lua_c_calls_lua.htm#_Anatomy_of_a_Lua_Call
 *  http://acamara.es/blog/2012/08/passing-variables-from-lua-5-2-to-c-and-vice-versa/
 *  https://john.nachtimwald.com/2014/07/12/wrapping-a-c-library-in-lua/
 */

#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <dirent.h>

#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"

#include "ctl-binding.h"
#include "wrap-json.h"

#define LUA_FIRST_ARG 2  // when using luaL_newlib calllback receive libtable as 1st arg
#define LUA_MSG_MAX_LENGTH 255

static  lua_State* luaState;

typedef enum {
    LUA_DOCALL,
    LUA_DOSTRING,
    LUA_DOSCRIPT,
} LuaDoActionT;

#define CTX_MAGIC 123456789
#define CTX_TOKEN "AFB_ctx"

typedef struct {
    int ctxMagic;
    afb_req request;
    char *info;
} LuaAfbContextT;

typedef struct {
  const char *callback;
  const char *handle;  
} LuaCallServiceT;

typedef enum {
    AFB_MSG_INFO,
    AFB_MSG_WARNING,
    AFB_MSG_NOTICE,      
    AFB_MSG_DEBUG,      
    AFB_MSG_ERROR,      
} LuaAfbMessageT;

/*
 * Note(Fulup): I fail to use luaL_setmetatable and replaced it with a simple opaque
 * handle while waiting for someone smarter than me to find a better solution
 *  https://stackoverflow.com/questions/45596493/lua-using-lua-newuserdata-from-lua-pcall
 */

STATIC LuaAfbContextT *LuaCtxCheck (lua_State *luaState, int index) {
  LuaAfbContextT *afbContext;
  //luaL_checktype(luaState, index, LUA_TUSERDATA);
  //afbContext = (LuaAfbContextT *)luaL_checkudata(luaState, index, CTX_TOKEN);
  luaL_checktype(luaState, index, LUA_TLIGHTUSERDATA);
  afbContext = (LuaAfbContextT *) lua_touserdata(luaState, index);
  if (afbContext == NULL && afbContext->ctxMagic != CTX_MAGIC) {
      luaL_error(luaState, "Fail to retrieve user data context=%s", CTX_TOKEN);
      AFB_ERROR ("afbContextCheck error retrieving afbContext");
      return NULL;
  }
  return afbContext;
}

STATIC LuaAfbContextT *LuaCtxPush (lua_State *luaState, afb_req request, const char* info) {
  // LuaAfbContextT *afbContext = (LuaAfbContextT *)lua_newuserdata(luaState, sizeof(LuaAfbContextT));
  // luaL_setmetatable(luaState, CTX_TOKEN);
  LuaAfbContextT *afbContext = (LuaAfbContextT *)calloc(1, sizeof(LuaAfbContextT));
  lua_pushlightuserdata(luaState, afbContext);
  if (!afbContext) {
      AFB_ERROR ("LuaCtxPush fail to allocate user data context");
      return NULL;
  }
  afbContext->ctxMagic=CTX_MAGIC;
  afbContext->info=strdup(info);
  afbContext->request= request;
  return afbContext;
}

STATIC void LuaCtxFree (LuaAfbContextT *afbContext) {   
    free (afbContext->info);
}

// List Avaliable Configuration Files
PUBLIC json_object* ScanForConfig (char* searchPath, char *pre, char *ext) {
    json_object *responseJ;
    DIR  *dirHandle;
    char *dirPath;
    char* dirList= strdup(searchPath);
    size_t extLen=0;        
    
    void ScanDir (char *dirpath) {
        struct dirent *dirEnt;
        dirHandle = opendir (dirPath);
        if (!dirHandle) {
            AFB_NOTICE ("CONFIG-SCANNING dir=%s not readable", dirPath);
            return;
        } 
        
        AFB_NOTICE ("CONFIG-SCANNING:ctl_listconfig scanning: %s", dirPath);
        while ((dirEnt = readdir(dirHandle)) != NULL) {
            
            // recursively search embedded directories ignoring any directory starting by '.' or '_'
            if (dirEnt->d_type == DT_DIR) {
                char newpath[CONTROL_MAXPATH_LEN];
                if (dirEnt->d_name[0]=='.' || dirEnt->d_name[0]=='_') continue;
                
                strncpy(newpath, dirpath, sizeof(newpath)); 
                strncat(newpath, "/", sizeof(newpath)); 
                strncat(newpath, dirEnt->d_name, sizeof(newpath)); 
            }
            
            // Unknown type is accepted to support dump filesystems
            if (dirEnt->d_type == DT_REG || dirEnt->d_type == DT_UNKNOWN) {

                // check prefix and extention
                size_t extIdx=strlen(dirEnt->d_name)-extLen;
                if (extIdx <= 0) continue; 
                if (pre && !strcasestr (dirEnt->d_name, pre)) continue;    
                if (ext && strcasecmp (ext, &dirEnt->d_name[extIdx])) continue;    

                struct json_object *pathJ = json_object_new_object();
                json_object_object_add(pathJ, "dirpath", json_object_new_string(dirPath));
                json_object_object_add(pathJ, "filename", json_object_new_string(dirEnt->d_name));
                json_object_array_add(responseJ, pathJ);
            }
        closedir(dirHandle);
        }
    }

    if (ext) extLen=strlen(ext);
    responseJ = json_object_new_array();
    
    // loop recursively on dir
    for (dirPath= strtok(dirList, ":"); dirPath && *dirPath; dirPath=strtok(NULL,":")) {
         ScanDir (dirPath);
    }
    
    free (dirList);    
    return (responseJ);
}

STATIC int LuaPushArgument (json_object *arg) {
    
    switch (json_object_get_type(arg)) {
        case json_type_object:
            lua_newtable (luaState);
            json_object_object_foreach (arg, key, val) {
                int done = LuaPushArgument (val);
                if (done) {
                    lua_pushstring(luaState, key); // table.key = val
                    lua_settable(luaState, -3);  
                }
            }

            break;
        case json_type_int:
            lua_pushinteger(luaState, json_object_get_int(arg));
            break;
        case json_type_string:
            lua_pushstring(luaState, json_object_get_string(arg));
            break;
        case json_type_boolean:
            lua_pushboolean(luaState, json_object_get_boolean(arg));
            break;
        case json_type_double:
            lua_pushnumber(luaState, json_object_get_double(arg));
            break;
        default:
            return 0;
    }
    
    return 1;
}

STATIC  json_object *PopOneArg (lua_State* luaState, int idx);
STATIC json_object *LuaTableToJson (lua_State* luaState, int index) {

    json_object *tableJ= json_object_new_object();
    const char *key;
    char number[3];
    lua_pushnil(luaState); // 1st key
    for (int jdx=1; lua_next(luaState, index) != 0; jdx++) {

        //printf("jdx=%d %s - %s\n", jdx,
        //lua_typename(luaState, lua_type(luaState, -2)),
        //lua_typename(luaState, lua_type(luaState, -1)));

        // uses 'key' (at index -2) and 'value' (at index -1)
        if (lua_type(luaState,-2) == LUA_TSTRING) key= lua_tostring(luaState, -2);
        else {
            snprintf(number, sizeof(number),"%d", jdx);
            key=number;
        } 
         
        json_object_object_add(tableJ, key, PopOneArg(luaState, -1));
        lua_pop(luaState, 1); // removes 'value'; keeps 'key' for next iteration 
    } 
    
    return tableJ;
}

STATIC  json_object *PopOneArg (lua_State* luaState, int idx) {
    json_object *value=NULL;

    int luaType = lua_type(luaState, idx);
    switch(luaType)  {
        case LUA_TNUMBER:
            value= json_object_new_double(lua_tonumber(luaState, idx));
            break;
        case LUA_TBOOLEAN:
            value=  json_object_new_boolean(lua_toboolean(luaState, idx));
            break;
        case LUA_TSTRING:
           value=  json_object_new_string(lua_tostring(luaState, idx));
            break;
        case LUA_TTABLE: {
            AFB_NOTICE ("-++-- luatable idx=%d ", idx);
            value= LuaTableToJson(luaState, idx);
            break;                
        }    
        default:
            AFB_NOTICE ("PopOneArg: script returned Unknown/Unsupported idx=%d type:%d/%s", idx, luaType, lua_typename(luaState, luaType));
            value=NULL;
    }

    return value;
}
    
static json_object *LuaPopArgs (lua_State* luaState, int start) {    
    json_object *responseJ;
    
    int stop = lua_gettop(luaState);
    if(stop-start <=0) return NULL;
    
    // start at 2 because we are using a function array lib
    if (start == stop) {
        responseJ=PopOneArg (luaState, start);
    } else {
        // loop on remaining return arguments
        responseJ= json_object_new_array();
        for (int idx=start; idx <= stop; idx++) {
            json_object_array_add(responseJ, PopOneArg (luaState, idx));     
       }
    }
    
    return responseJ;
}


STATIC void LuaFormatMessage(lua_State* luaState, LuaAfbMessageT action) {
    char *message;

    json_object *responseJ= LuaPopArgs(luaState, LUA_FIRST_ARG);
    if (!responseJ) {
        message="--";
        goto PrintMessage;
    }           
    
    // if we have only on argument just return the value.
    if (json_object_get_type(responseJ)!=json_type_array || json_object_array_length(responseJ) <2) {
        message= (char*)json_object_get_string(responseJ);
        goto PrintMessage;
    }
    
    // extract format and push all other parameter on the stack
    message = alloca (LUA_MSG_MAX_LENGTH);
    const char *format = json_object_get_string(json_object_array_get_idx(responseJ, 0));
    
    int arrayIdx=1;
    int targetIdx=0;
    
    for (int idx=0; format[idx] !='\0'; idx++) {
        
        if (format[idx]=='%' && format[idx] !='\0') {
            json_object *slotJ= json_object_array_get_idx(responseJ, arrayIdx);

            switch (format[++idx]) {
                case 'd':
                    targetIdx += snprintf (&message[targetIdx], LUA_MSG_MAX_LENGTH-targetIdx,"%d", json_object_get_int(slotJ)); 
                    break;
                case 'f':
                    targetIdx += snprintf (&message[targetIdx], LUA_MSG_MAX_LENGTH-targetIdx,"%f", json_object_get_double(slotJ)); 
                    break;
                    
                case 's':
                default:
                    targetIdx += snprintf (&message[targetIdx], LUA_MSG_MAX_LENGTH-targetIdx,"%s", json_object_get_string(slotJ));                     
            }
            
        } else {
            message[targetIdx++] = format[idx];
        }
    }

PrintMessage:    
    switch (action) {
        case  AFB_MSG_WARNING:
            AFB_WARNING (message);
            break;
        case AFB_MSG_NOTICE:
            AFB_NOTICE (message);
            break;
        case AFB_MSG_DEBUG:
            AFB_DEBUG (message);
            break;
        case AFB_MSG_INFO:
            AFB_INFO (message);
            break;
        case AFB_MSG_ERROR:       
        default:
            AFB_ERROR (message);            
    }
}

STATIC int LuaPrintInfo(lua_State* luaState) { 
    LuaFormatMessage (luaState, AFB_MSG_INFO);
    return 0; // no value return
}

STATIC int LuaPrintError(lua_State* luaState) { 
    LuaFormatMessage (luaState, AFB_MSG_ERROR);
    return 0; // no value return
}

STATIC int LuaPrintWarning(lua_State* luaState) { 
    LuaFormatMessage (luaState, AFB_MSG_WARNING);
    return 0; // no value return
}

STATIC int LuaPrintNotice(lua_State* luaState) { 
    LuaFormatMessage (luaState, AFB_MSG_NOTICE);
    return 0; // no value return
}

STATIC int LuaPrintDebug(lua_State* luaState) { 
    LuaFormatMessage (luaState, AFB_MSG_DEBUG);
    return 0; // no value return
}

STATIC int LuaAfbSuccess(lua_State* luaState) {
    LuaAfbContextT *afbContext= LuaCtxCheck(luaState, LUA_FIRST_ARG);
    if (!afbContext) goto OnErrorExit;
    
    // ignore context argument
    json_object *responseJ= LuaPopArgs(luaState, LUA_FIRST_ARG+1);
        
    afb_req_success(afbContext->request, responseJ, NULL);

    LuaCtxFree(afbContext);
    return 0;
 
 OnErrorExit:  
        lua_error(luaState);
        return 1;
}

STATIC int LuaAfbFail(lua_State* luaState) {
    LuaAfbContextT *afbContext= LuaCtxCheck(luaState, LUA_FIRST_ARG);
    if (!afbContext) goto OnErrorExit;
    
    json_object *responseJ= LuaPopArgs(luaState, LUA_FIRST_ARG+1);

    afb_req_fail(afbContext->request, afbContext->info, json_object_get_string(responseJ));
    
    LuaCtxFree(afbContext);    
    return 0;   

 OnErrorExit:  
        lua_error(luaState);
        return 1;
}

STATIC void LuaAfbServiceCB(void *handle, int iserror, struct json_object *responseJ) { 
    LuaCallServiceT *contextCB= (LuaCallServiceT*)handle;
    
    // load function (should exist in CONTROL_PATH_LUA
    lua_getglobal(luaState, contextCB->callback);

    // push error status & response
    lua_pushboolean(luaState, iserror);
    (void)LuaPushArgument(responseJ);
    
    int err=lua_pcall(luaState, 2, LUA_MULTRET, 0);
    if (err) {
        AFB_ERROR ("LUA-SERICE-CB:FAIL response=%s err=%s", json_object_get_string(responseJ), lua_tostring(luaState,-1) );
    }
}

STATIC int LuaAfbService(lua_State* luaState) {
    int count = lua_gettop(luaState);
    
    // retrieve userdate context
    LuaAfbContextT *afbContext= luaL_checkudata(luaState, 1, "CTX_TOKEN");
    if (!afbContext) {
        lua_pushliteral (luaState, "LuaAfbServiceCall-Hoops no CTX_TOKEN");
        goto OnErrorExit;
    }
    
    if (count <5 || !lua_isstring(luaState, 2) || !lua_isstring(luaState, 3) || !lua_istable(luaState, 4) || !lua_isstring(luaState, 5)) {
        lua_pushliteral (luaState, "LuaAfbServiceCall-Syntax is AFB_service_call (api, verb, query, callback, handle");
        goto OnErrorExit;        
    }
    
    LuaCallServiceT *contextCB = calloc (1, sizeof(LuaCallServiceT));  
    
    // get api/verb+query
    const char *api = lua_tostring(luaState,1);
    const char *verb= lua_tostring(luaState,2);    
    json_object *queryJ= LuaTableToJson(luaState, 3);
    if (!queryJ) goto OnErrorExit;
    
    if (count >= 6) {
        if (!lua_istable(luaState, 6)) {
            lua_pushliteral (luaState, "LuaAfbServiceCall-Syntax optional handle should be a table");
            goto OnErrorExit;                    
        }
        contextCB->handle= lua_tostring(luaState, 5);
    }    
        
    afb_service_call(api, verb, queryJ, LuaAfbServiceCB, contextCB);
    
    return 0; // no value return
 
  OnErrorExit:  
        lua_error(luaState);
        return 1;

}


// Generated some fake event based on watchdog/counter
PUBLIC void LuaDoAction (LuaDoActionT action, afb_req request) {
    
    int err, count=0;

    json_object* queryJ = afb_req_json(request);  
    
    switch (action) {
        
        case LUA_DOSTRING: {
            const char *script = json_object_get_string(queryJ);
            err=luaL_loadstring(luaState, script);
            if (err) {
                AFB_ERROR ("LUA-DO-COMPILE:FAIL String=%s err=%s", script, lua_tostring(luaState,-1) );
                goto OnErrorExit;
            }
            // Push AFB client context on the stack
            LuaAfbContextT *afbContext= LuaCtxPush(luaState, request, script);
            if (!afbContext) goto OnErrorExit;
            
            break;
        }
    
        case LUA_DOCALL: {
            const char *func;
            json_object *args;
            err= wrap_json_unpack (queryJ, "{s:s, s?o !}", "func",  &func,"args", &args);
            if (err) {
                AFB_ERROR ("LUA-DOCALL-SYNTAX missing func|args args=%s", json_object_get_string(queryJ));
                goto OnErrorExit;
            }

                
            // load function (should exist in CONTROL_PATH_LUA
            lua_getglobal(luaState, func);
                          
            // Push AFB client context on the stack
            LuaAfbContextT *afbContext= LuaCtxPush(luaState, request, func);
            if (!afbContext) goto OnErrorExit;

            // push arguments on the stack
            if (json_object_get_type(args) != json_type_array) { 
                count= LuaPushArgument (args);
            } else {
                for (int idx=0; idx<json_object_array_length(args); idx++)  {
                    count += LuaPushArgument (json_object_array_get_idx(args, idx));
                    if (err) break;
                }
            } 
            
            break;
        }
            
        case LUA_DOSCRIPT: {
            const char *script;
            json_object *args;
            int index;
            
            // scan luascript search path once
            static json_object *luaScriptPathJ =NULL;
            if (!luaScriptPathJ)  luaScriptPathJ= ScanForConfig(CONTROL_LUA_PATH , NULL, "lua");

            err= wrap_json_unpack (queryJ, "{s:s, s?o s?o !}", "script", &script,"args", &args, "arg", &args);
            if (err) {
                AFB_ERROR ("LUA-DOCALL-SYNTAX missing script|(args,arg) args=%s", json_object_get_string(queryJ));
                goto OnErrorExit;
            }
 
                       // Push AFB client context on the stack
            LuaAfbContextT *afbContext= LuaCtxPush(luaState, request, script);
            if (!afbContext) goto OnErrorExit;

            // push arguments on the stack
            if (json_object_get_type(args) != json_type_array) { 
                lua_createtable(luaState, 1, 0);
                count= LuaPushArgument (args);
            } else {
                int length= json_object_array_length(args);
                lua_createtable(luaState, length, 0);
                for (int idx=0; idx < length; idx++)  {
                    count += LuaPushArgument (json_object_array_get_idx(args, idx));
                    if (err) break;
                }
            } 

            for (index=0; index < json_object_array_length(luaScriptPathJ); index++) {
                char *filename; char*dirpath;
                json_object *entryJ=json_object_array_get_idx(luaScriptPathJ, index);

                err= wrap_json_unpack (entryJ, "{s:s, s:s !}", "dirpath",  &dirpath,"filename", &filename);
                if (err) {
                    AFB_ERROR ("LUA-DOSCRIPT HOOPs invalid LUA script path = %s", json_object_get_string(entryJ));
                    goto OnErrorExit;
                }
                
                if (strcmp(filename, script)) continue;

                char filepath[255];
                strncpy(filepath, dirpath, sizeof(filepath)); 
                strncat(filepath, "/", sizeof(filepath)); 
                strncat(filepath, filename, sizeof(filepath)); 
                err= luaL_loadfile(luaState, filepath);   
                if (err) {
                    AFB_ERROR ("LUA-DOSCRIPT HOOPs Error in LUA loading scripts=%s err=%s", filepath, lua_tostring(luaState,-1));
                    goto OnErrorExit;
                }
                break;
            }
        
            if (index == json_object_array_length(luaScriptPathJ)) {
                AFB_ERROR ("LUA-DOSCRIPT HOOPs script=%s not in path=%s", script, CONTROL_LUA_PATH);
                goto OnErrorExit;
            }
            
            break;
        }
                
        default: 
            AFB_ERROR ("LUA-DOCALL-ACTION unknown query=%s", json_object_get_string(queryJ));
            goto OnErrorExit;
    }
       
    // effectively exec LUA code (afb_reply/fail done later from callback) 
    err=lua_pcall(luaState, count+1, 0, 0);
    if (err) {
        AFB_ERROR ("LUA-DO-EXEC:FAIL query=%s err=%s", json_object_get_string(queryJ), lua_tostring(luaState,-1) );
        goto OnErrorExit;
    }

    return;
    
 OnErrorExit:
    afb_req_fail(request,"LUA:ERROR", lua_tostring(luaState,-1));
    return;
}

PUBLIC void ctlapi_lua_dostring (afb_req request) {       
    LuaDoAction (LUA_DOSTRING, request);
}

PUBLIC void ctlapi_lua_docall (afb_req request) {
    LuaDoAction (LUA_DOCALL, request);
}

PUBLIC void ctlapi_lua_doscript (afb_req request) {
    LuaDoAction (LUA_DOSCRIPT, request);
}

static const luaL_Reg afbFunction[] = {
    {"notice" , LuaPrintNotice},
    {"info"   , LuaPrintInfo},
    {"warning", LuaPrintWarning},
    {"debug"  , LuaPrintDebug},
    {"error"  , LuaPrintError},
    {"service", LuaAfbService},
    {"success", LuaAfbSuccess},
    {"fail"   , LuaAfbFail},
    {NULL, NULL}  /* sentinel */
};

// Create Binding Event at Init
PUBLIC int LuaLibInit () {
    int err, index;
          
    // search for default policy config file
    json_object *luaScriptPathJ = ScanForConfig(CONTROL_LUA_PATH , "onload", "lua");
    
    // open a new LUA interpretor
    luaState = luaL_newstate();
    if (!luaState)  {
        AFB_ERROR ("LUA_INIT: Fail to open lua interpretor");
        goto OnErrorExit;
    }
    
    // load auxiliary libraries
    luaL_openlibs(luaState);

    // redirect print to AFB_NOTICE    
    luaL_newlib(luaState, afbFunction);
    lua_setglobal(luaState, "AFB");
    
    // load+exec any file found in LUA search path
    for (index=0; index < json_object_array_length(luaScriptPathJ); index++) {
        json_object *entryJ=json_object_array_get_idx(luaScriptPathJ, index);
        
        char *filename; char*dirpath;
        err= wrap_json_unpack (entryJ, "{s:s, s:s !}", "dirpath",  &dirpath,"filename", &filename);
        if (err) {
            AFB_ERROR ("LUA-INIT HOOPs invalid config file path = %s", json_object_get_string(entryJ));
            goto OnErrorExit;
        }
        
        char filepath[CONTROL_MAXPATH_LEN];
        strncpy(filepath, dirpath, sizeof(filepath)); 
        strncat(filepath, "/", sizeof(filepath)); 
        strncat(filepath, filename, sizeof(filepath)); 
        err= luaL_loadfile(luaState, filepath);   
        if (err) {
            AFB_ERROR ("LUA-LOAD HOOPs Error in LUA loading scripts=%s err=%s", filepath, lua_tostring(luaState,-1));
            goto OnErrorExit;
        }
        
        // exec/compil script
        err = lua_pcall(luaState, 0, 0, 0);
        if (err) {
            AFB_ERROR ("LUA-LOAD HOOPs Error in LUA exec scripts=%s err=%s", filepath, lua_tostring(luaState,-1));
            goto OnErrorExit;
        }    
    }
    
    // no policy config found remove control API from binder
    if (index == 0)  {
        AFB_WARNING ("POLICY-INIT:WARNING No Control LUA file in path=[%s]", CONTROL_LUA_PATH);
    }
       
    AFB_DEBUG ("Audio control-LUA Init Done");
    return 0;
    
 OnErrorExit:    
    return -1;
}