summaryrefslogtreecommitdiffstats
path: root/vpp-api/lua/examples/lute/lute.lua
blob: 89b9924b9016a4c2c33922fe352c97aa7913e699 (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
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
--[[
version = 1
/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * 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.
 */
]]

-- LUTE: Lua Unit Test Environment
-- AKA what happens when screen tries to marry with lua and expect,
-- but escapes mid-ceremony.
--
-- comments: @ayourtch

ffi = require("ffi")

vpp = {}
function vpp.dump(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..'] = ' .. vpp.dump(v) .. ','
      end
      return s .. '} '
   else
      return tostring(o)
   end
end


ffi.cdef([[

int posix_openpt(int flags);
int grantpt(int fd);
int unlockpt(int fd);
char *ptsname(int fd);

typedef long pid_t;
typedef long ssize_t;
typedef long size_t;
typedef int nfds_t;
typedef long time_t;
typedef long suseconds_t;

pid_t fork(void);
pid_t setsid(void);

int close(int fd);
int open(char *pathname, int flags);

int dup2(int oldfd, int newfd);

ssize_t read(int fd, void *buf, size_t count);
ssize_t write(int fd, const void *buf, size_t count);

struct pollfd {
               int   fd;         /* file descriptor */
               short events;     /* requested events */
               short revents;    /* returned events */
           };

int poll(struct pollfd *fds, nfds_t nfds, int timeout);

struct timeval {
               time_t      tv_sec;     /* seconds */
               suseconds_t tv_usec;    /* microseconds */
           };

int gettimeofday(struct timeval *tv, struct timezone *tz);

int inet_pton(int af, const char *src, void *dst);

]])

ffi.cdef([[
void *memset(void *s, int c, size_t n);
void *memcpy(void *dest, void *src, size_t n);
void *memmove(void *dest, const void *src, size_t n);
void *memmem(const void *haystack, size_t haystacklen,
        const void *needle, size_t needlelen);
]])



local O_RDWR = 2


function os_time()
  local tv = ffi.new("struct timeval[1]")
  local ret = ffi.C.gettimeofday(tv, nil)
  return tonumber(tv[0].tv_sec) + (tonumber(tv[0].tv_usec)/1000000.0)
end

function sleep(n)
  local when_wakeup = os_time() + n
  while os_time() <= when_wakeup do
    ffi.C.poll(nil, 0, 10)
  end
end


function c_str(text_in)
  local text = text_in 
  local c_str = ffi.new("char[?]", #text+1)
  ffi.copy(c_str, text)
  return c_str
end

function ip46(addr_text)
  local out = ffi.new("char [200]")
  local AF_INET6 = 10
  local AF_INET = 2
  local is_ip6 = ffi.C.inet_pton(AF_INET6, c_str(addr_text), out)
  if is_ip6 == 1 then
    return ffi.string(out, 16), true
  end
  local is_ip4 = ffi.C.inet_pton(AF_INET, c_str(addr_text), out)
  if is_ip4 then
    return (string.rep("4", 12).. ffi.string(out, 4)), false
  end
end

function pty_master_open()
  local fd = ffi.C.posix_openpt(O_RDWR)
  ffi.C.grantpt(fd)
  ffi.C.unlockpt(fd)
  local p = ffi.C.ptsname(fd)
  print("PTS:" .. ffi.string(p))
  return fd, ffi.string(p)
end

function pty_run(cmd)
  local master_fd, pts_name = pty_master_open()
  local child_pid = ffi.C.fork()
  if (child_pid == -1) then
    print("Error fork()ing")
    return -1
  end 
 
  if child_pid ~= 0 then
    -- print("Parent")
    return master_fd, child_pid
  end

  -- print("Child")
  if (ffi.C.setsid() == -1) then
    print("Child error setsid")
    os.exit(-1)
  end

  ffi.C.close(master_fd)

  local slave_fd = ffi.C.open(c_str(pts_name), O_RDWR)
  if slave_fd == -1 then
    print("Child can not open slave fd")
    os.exit(-2)
  end

  ffi.C.dup2(slave_fd, 0)
  ffi.C.dup2(slave_fd, 1)
  ffi.C.dup2(slave_fd, 2)
  os.execute(cmd)
end

function readch()
  local buf = ffi.new("char[1]")
  local nread= ffi.C.read(0, buf, 1)
  -- print("\nREADCH : " .. string.char(buf[0]))
  return string.char(buf[0])
end

function stdout_write(str)
  ffi.C.write(1, c_str(str), #str)
end


readln = {
split = function(str, pat)
  local t = {}  -- NOTE: use {n = 0} in Lua-5.0
  local fpat = "(.-)" .. pat
  local last_end = 1
  if str then
    local s, e, cap = str:find(fpat, 1)
    while s do
      if s ~= 1 or cap ~= "" then
        table.insert(t,cap)
      end
      last_end = e+1
      s, e, cap = str:find(fpat, last_end)
    end
    if last_end <= #str then
      cap = str:sub(last_end)
      table.insert(t, cap)
    end
  end
  return t
end,

reader = function()
  local rl = {}

  rl.init = function()
    os.execute("stty -icanon min 1 -echo")
    rl.rawmode = true
  end

  rl.done = function()
    os.execute("stty icanon echo")
    rl.rawmode = false
  end

  rl.prompt = ">"
  rl.history = { "" }
  rl.history_index = 1
  rl.history_length = 1

  rl.hide_cmd = function()
    local bs = string.char(8) .. " " .. string.char(8)
    for i = 1, #rl.command do
      stdout_write(bs)
    end
  end

  rl.show_cmd = function()
    if rl.command then
      stdout_write(rl.command)
    end
  end

  rl.store_history = function(cmd)
    if cmd == "" then
      return
    end
    rl.history[rl.history_length] = cmd
    rl.history_length = rl.history_length + 1
    rl.history_index = rl.history_length
    rl.history[rl.history_length] = ""
  end

  rl.readln = function(stdin_select_fn, batch_cmd, batch_when, batch_expect)
    local done = false
    local need_prompt = true
    rl.command = ""

    if not rl.rawmode then
      rl.init()
    end

    while not done do
      local indent_value = #rl.prompt + #rl.command
      if need_prompt then
        stdout_write(rl.prompt)
        stdout_write(rl.command)
        need_prompt = false
      end
      if type(stdin_select_fn) == "function" then
        while not stdin_select_fn(indent_value, batch_cmd, batch_when, batch_expect) do
          stdout_write(rl.prompt)
          stdout_write(rl.command)
          indent_value = #rl.prompt + #rl.command
        end
        if batch_cmd and ((os_time() > batch_when) or (batch_expect and expect_success(batch_expect, buf, 0))) then
          stdout_write("\n" .. rl.prompt .. batch_cmd .. "\n")
          if batch_expect then
            expect_done(batch_expect)
          end
          return batch_cmd, batch_expect
        end
      end
      local ch = readch()
      if ch:byte(1) == 27 then
        -- CONTROL
        local ch2 = readch()
        -- arrows
        if ch2:byte(1) == 91 then
          local ch3 = readch()
          local b = ch3:byte(1)
          if b == 65 then
            ch = "UP"
          elseif b == 66 then
            ch = "DOWN"
          elseif b == 67 then
            ch = "RIGHT"
          elseif b == 68 then
            ch = "LEFT"
          end
          -- print("Byte: " .. ch3:byte(1))
          -- if ch3:byte(1)
        end
      end

      if ch == "?" then
        stdout_write(ch)
        stdout_write("\n")
        if rl.help then
          rl.help(rl)
        end
        need_prompt = true
      elseif ch == "\t" then
        if rl.tab_complete then
          rl.tab_complete(rl)
        end
        stdout_write("\n")
        need_prompt = true
      elseif ch == "\n" then
        stdout_write(ch)
        done = true
      elseif ch == "\004" then
        stdout_write("\n")
        rl.command = nil
        done = true
      elseif ch == string.char(127) then
        if rl.command ~= "" then
          stdout_write(string.char(8) .. " " .. string.char(8))
          rl.command = string.sub(rl.command, 1, -2)
        end
      elseif #ch > 1 then
        -- control char
        if ch == "UP" then
          rl.hide_cmd()
          if rl.history_index == #rl.history then
            rl.history[rl.history_index] = rl.command
          end
          if rl.history_index > 1 then
            rl.history_index = rl.history_index - 1
            rl.command = rl.history[rl.history_index]
          end
          rl.show_cmd()
        elseif ch == "DOWN" then
          rl.hide_cmd()
          if rl.history_index < rl.history_length then
            rl.history_index = rl.history_index + 1
            rl.command = rl.history[rl.history_index]
          end
          rl.show_cmd()
        end
      else
        stdout_write(ch)
        rl.command = rl.command .. ch
      end
    end
    if rl.command then
      rl.store_history(rl.command)
    end
    return rl.command
  end
  return rl
end

}

local select_fds = {}
local sessions = {}

local line_erased = false

function erase_line(indent)
  if not line_erased then
    line_erased = true
    stdout_write(string.rep(string.char(8), indent)..string.rep(" ", indent)..string.rep(string.char(8), indent))
  end
end

function do_select_stdin(indent, batch_cmd, batch_when, batch_expect)
  while true do
    local nfds = 1+#select_fds
    local pfds = ffi.new("struct pollfd[?]", nfds)
    pfds[0].fd = 0;
    pfds[0].events = 1;
    pfds[0].revents = 0;
    for i = 1,#select_fds do
      pfds[i].fd = select_fds[i].fd
      pfds[i].events = 1
      pfds[i].revents = 0
    end
    if batch_cmd and ((os_time() > batch_when) or (batch_expect and expect_success(batch_expect, buf, 0))) then
      return true
    end
    while ffi.C.poll(pfds, nfds, 10) == 0 do
      if batch_cmd and ((os_time() > batch_when) or (batch_expect and expect_success(batch_expect, buf, 0))) then
        return true
      end
      if line_erased then
        line_erased = false
        return false
      end
    end
    if pfds[0].revents == 1 then
      return true
    end
    for i = 1,#select_fds do
      if(pfds[i].revents > 0) then
        if pfds[i].fd ~= select_fds[i].fd then
          print("File descriptors unequal", pfds[i].fd, select_fds[i].fd)
        end
        select_fds[i].cb(select_fds[i], pfds[i].revents, indent)
      end
    end
  end
end

local buf = ffi.new("char [32768]")

function session_stdout_write(prefix, data)
  data = prefix .. data:gsub("\n", "\n"..prefix):gsub("\n"..prefix.."$", "\n")
  
  stdout_write(data)
end

function expect_success(sok, buf, nread)
  local expect_buf_sz = ffi.sizeof(sok.expect_buf) - 128
  local expect_buf_avail = expect_buf_sz - sok.expect_buf_idx
  -- print("EXPECT_SUCCESS: nread ".. tostring(nread).. " expect_buf_idx: " .. tostring(sok.expect_buf_idx) .. " expect_buf_avail: " .. tostring(expect_buf_avail) )
  if expect_buf_avail < 0 then
    print "EXPECT BUFFER OVERRUN ALREADY"
    os.exit(1)
  end
  if expect_buf_avail < nread then
    if (nread >= ffi.sizeof(sok.expect_buf)) then
      print("Read too large of a chunk to fit into expect buffer")
      return nil
    end
    local delta = nread - expect_buf_avail

    ffi.C.memmove(sok.expect_buf, sok.expect_buf + delta, expect_buf_sz - delta)
    sok.expect_buf_idx = sok.expect_buf_idx - delta
    expect_buf_avail = nread 
  end
  if sok.expect_buf_idx + nread > expect_buf_sz then
    print("ERROR, I have just overrun the buffer !")
    os.exit(1)
  end
  ffi.C.memcpy(sok.expect_buf + sok.expect_buf_idx, buf, nread)
  sok.expect_buf_idx = sok.expect_buf_idx + nread
  if sok.expect_str == nil then
    return true
  end
  local match_p = ffi.C.memmem(sok.expect_buf, sok.expect_buf_idx, sok.expect_str, sok.expect_str_len)
  if match_p ~= nil then
    return true
  end
  return false
end

function expect_done(sok)
  local expect_buf_sz = ffi.sizeof(sok.expect_buf) - 128
  if not sok.expect_str then 
    return false
  end
  local match_p = ffi.C.memmem(sok.expect_buf, sok.expect_buf_idx, sok.expect_str, sok.expect_str_len)
  if match_p ~= nil then
    if sok.expect_cb then
      sok.expect_cb(sok)
    end
    local match_idx = ffi.cast("char *", match_p) - ffi.cast("char *", sok.expect_buf)
    ffi.C.memmove(sok.expect_buf, ffi.cast("char *", match_p) + sok.expect_str_len, expect_buf_sz - match_idx - sok.expect_str_len)
    sok.expect_buf_idx = match_idx + sok.expect_str_len
    sok.expect_success = true

    sok.expect_str = nil
    sok.expect_str_len = 0
    return true
  end
end

function slave_events(sok, revents, indent)
  local fd = sok.fd
  local nread = ffi.C.read(fd, buf, ffi.sizeof(buf)-128)
  local idx = nread - 1
  while idx >= 0 and buf[idx] ~= 10 do
    idx = idx - 1
  end
  if idx >= 0 then
    erase_line(indent)
    session_stdout_write(sok.prefix, sok.buf .. ffi.string(buf, idx+1))
    sok.buf = ""
  end
  sok.buf = sok.buf .. ffi.string(buf+idx+1, nread-idx-1)
  -- print("\nRead: " .. tostring(nread))
  -- stdout_write(ffi.string(buf, nread))
  if expect_success(sok, buf, nread) then
    return true
  end
  return false
end


function start_session(name)
  local mfd, cpid = pty_run("/bin/bash")
  local sok =  { ["fd"] = mfd, ["cb"] = slave_events, ["buf"] = "", ["prefix"] = name .. ":", ["expect_buf"] = ffi.new("char [165536]"), ["expect_buf_idx"] = 0, ["expect_str"] = nil }
  table.insert(select_fds, sok)
  sessions[name] = sok
end

function command_transform(exe)
  if exe == "break" then
    exe = string.char(3)
  end
  return exe
end

function session_write(a_session, a_str)
  if has_session(a_session) then
    return tonumber(ffi.C.write(sessions[a_session].fd, c_str(a_str), #a_str))
  else
    return 0
  end
end

function session_exec(a_session, a_cmd)
  local exe = command_transform(a_cmd) .. "\n"
  session_write(a_session, exe)
end

function session_cmd(ui, a_session, a_cmd)
  if not has_session(a_session) then
    stdout_write("ERR: No such session '" .. tostring(a_session) .. "'\n")
    return nil
  end
  if a_session == "lua" then
    local func, msg = loadstring(ui.lua_acc .. a_cmd)
    -- stdout_write("LOADSTR: " .. vpp.dump({ ret, msg }) .. "\n")
    if not func and string.match(msg, "<eof>") then
      if a_session ~= ui.in_session then
         stdout_write("ERR LOADSTR: " .. tostring(msg) .. "\n")
         return nil
      end
      ui.lua_acc = ui.lua_acc .. a_cmd  .. "\n"
      return true
    end
    ui.lua_acc = ""
    local ret, msg = pcall(func)
    if ret then
      return true
    else
      stdout_write("ERR: " .. msg .. "\n") 
      return nil
    end
  else
    session_exec(a_session, a_cmd)
    if ui.session_cmd_delay then
      return { "delay", ui.session_cmd_delay }
    end
    return true
  end
end

function has_session(a_session)
  if a_session == "lua" then
    return true
  end
  return (sessions[a_session] ~= nil)
end

function command_match(list, input, output)
  for i, v in ipairs(list) do
    local m = {}
    m[1], m[2], m[3], m[4], m[5], m[6], m[7], m[8], m[9] = string.match(input, v[1])
    -- print("MATCH: ", vpp.dump(m))
    if m[1] then
       output["result"] = m
       output["result_index"] = i
       return m
    end 
  end
  return nil
end

function cmd_spawn_shell(ui, a_arg)
  start_session(a_arg[1])
  return true
end

function cmd_run_cmd(ui, a_arg)
  local a_sess = a_arg[1]
  local a_cmd = a_arg[2]
  return session_cmd(ui, a_sess, a_cmd)
end

function cmd_cd(ui, a_arg)
  local a_sess = a_arg[1]
  if has_session(a_sess) then
    ui.in_session = a_sess
    return true
  else
    stdout_write("ERR: Unknown session '".. tostring(a_sess) .. "'\n")
    return nil
  end
end

function cmd_sleep(ui, a_arg)
  return { "delay", tonumber(a_arg[1]) }
end

function cmd_expect(ui, a_arg)
  local a_sess = a_arg[1]
  local a_expect = a_arg[2]
  local sok = sessions[a_sess]
  if not sok then
    stdout_write("ERR: unknown session '" .. tostring(a_sess) .. "'\n")
    return nil
  end
  sok.expect_str = c_str(a_expect)
  sok.expect_str_len = #a_expect
  return { "expect", a_sess }
end

function cmd_info(ui, a_arg)
  local a_sess = a_arg[1]
  local sok = sessions[a_sess]
  if not sok then
    stdout_write("ERR: unknown session '" .. tostring(a_sess) .. "'\n")
    return nil
  end
  print("Info for session " .. tostring(a_sess) .. "\n")
  print("Expect buffer index: " .. tostring(sok.expect_buf_idx))
  print("Expect buffer: '" .. tostring(ffi.string(sok.expect_buf, sok.expect_buf_idx)) .. "'\n")
  if sok.expect_str then
    print("Expect string: '" .. tostring(ffi.string(sok.expect_str, sok.expect_str_len)) .. "'\n")
  else
    print("Expect string not set\n")
  end
end

function cmd_echo(ui, a_arg)
  local a_data = a_arg[1]
  print("ECHO: " .. tostring(a_data))
end

main_command_table = {
  { "^shell ([a-zA-Z0-9_]+)$", cmd_spawn_shell },
  { "^run ([a-zA-Z0-9_]+) (.+)$", cmd_run_cmd },
  { "^cd ([a-zA-Z0-9_]+)$", cmd_cd  },
  { "^sleep ([0-9]+)$", cmd_sleep },
  { "^expect ([a-zA-Z0-9_]+) (.-)$", cmd_expect },
  { "^info ([a-zA-Z0-9_]+)$", cmd_info },
  { "^echo (.-)$", cmd_echo }
}



function ui_set_prompt(ui)
  if ui.in_session then 
    if ui.in_session == "lua" then
      if #ui.lua_acc > 0 then
        ui.r.prompt = ui.in_session .. ">>"
      else
        ui.r.prompt = ui.in_session .. ">"
      end 
    else
      ui.r.prompt = ui.in_session .. "> "
    end
  else
    ui.r.prompt = "> "
  end
  return ui.r.prompt
end

function ui_run_command(ui, cmd)
  -- stdout_write("Command: " .. tostring(cmd) .. "\n")
  local ret = false
  if ui.in_session then
    if cmd then
      if cmd == "^D^D^D" then
        ui.in_session = nil
        ret = true
      else
        ret = session_cmd(ui, ui.in_session, cmd)
      end
    else
      ui.in_session = nil
      ret = true
    end
  else  
    if cmd then
      local out = {}
      if cmd == "" then
        ret = true
      end
      if command_match(main_command_table, cmd, out) then
        local i = out.result_index
        local m = out.result
        if main_command_table[i][2] then
          ret = main_command_table[i][2](ui, m)
        end
      end
    end
    if not cmd or cmd == "quit" then
      return "quit"
    end
  end
  return ret
end

local ui = {}
ui.in_session = nil
ui.r = readln.reader() 
ui.lua_acc = ""
ui.session_cmd_delay = 0.3

local lines = ""

local done = false
-- a helper function which always returns nil
local no_next_line = function() return nil end

-- a function which returns the next batch line
local next_line = no_next_line

local batchfile = arg[1]

if batchfile then
  local f = io.lines(batchfile)
  next_line = function() 
    local line = f()
    if line then 
      return line
    else 
      next_line = no_next_line
      session_stdout_write(batchfile .. ":", "End of batch\n")
      return nil
    end
  end
end


local batch_when = 0
local batch_expect = nil
while not done do
  local prompt = ui_set_prompt(ui)
  local batch_cmd = next_line() 
  local cmd, expect_sok = ui.r.readln(do_select_stdin, batch_cmd, batch_when, batch_expect)
  if expect_sok and not expect_success(expect_sok, buf, 0) then
    if not cmd_ret and next_line ~= no_next_line then
      print("ERR: expect timeout\n")
      next_line = no_next_line
    end
  else 
    local cmd_ret = ui_run_command(ui, cmd)
    if not cmd_ret and next_line ~= no_next_line then
      print("ERR: Error during batch execution\n")
      next_line = no_next_line
    end

    if cmd_ret  == "quit" then
      done = true
    end
    batch_expect = nil
    batch_when = 0
    if type(cmd_ret) == "table" then
      if cmd_ret[1] == "delay" then
	batch_when = os_time() + tonumber(cmd_ret[2])
      end
      if cmd_ret[1] == "expect" then
	batch_expect = sessions[cmd_ret[2]]
	batch_when = os_time() + 15
      end
    end
  end
end
ui.r.done()

os.exit(1)