-
Notifications
You must be signed in to change notification settings - Fork 638
/
omprog.c
1281 lines (1083 loc) · 38.2 KB
/
omprog.c
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
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* omprog.c
* This output plugin enables rsyslog to execute a program and
* feed it the message stream as standard input.
*
* NOTE: read comments in module-template.h for more specifics!
*
* File begun on 2009-04-01 by RGerhards
*
* Copyright 2009-2020 Adiscon GmbH.
*
* This file is part of rsyslog.
*
* 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
* -or-
* see COPYING.ASL20 in the source distribution
*
* 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.
*/
#include "config.h"
#include <stdio.h>
#include <syslog.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <pthread.h>
#include <poll.h>
#include "rsyslog.h"
#include "conf.h"
#include "syslogd-types.h"
#include "srUtils.h"
#include "template.h"
#include "module-template.h"
#include "errmsg.h"
#include "cfsysline.h"
#include "glbl.h"
#include "rsconf.h"
MODULE_TYPE_OUTPUT
MODULE_TYPE_NOKEEP
MODULE_CNFNAME("omprog")
extern char **environ; /* POSIX environment ptr, by std not in a header... (see man 7 environ) */
/* internal structures
*/
DEF_OMOD_STATIC_DATA
#define NO_HUP_FORWARD -1 /* indicates that HUP should NOT be forwarded */
#define DEFAULT_CONFIRM_TIMEOUT_MS 10000
#define DEFAULT_CLOSE_TIMEOUT_MS 5000
#define RESPONSE_LINE_BUFFER_SIZE 4096
#define OUTPUT_CAPTURE_BUFFER_SIZE 4096
#define MAX_FD_TO_CLOSE 65535
typedef struct childProcessCtx {
int bIsRunning; /* is the program running? (if 0, next fields are uninitialized) */
pid_t pid; /* pid of currently running child process */
int fdPipeOut; /* fd for sending messages to the program */
int fdPipeIn; /* fd for receiving status messages from the program, or -1 */
} childProcessCtx_t;
typedef struct outputCaptureCtx {
uchar *szFileName; /* name of file to write the program output to, or NULL */
mode_t fCreateMode; /* output file creation permissions */
pthread_mutex_t mutStart; /* mutex for starting the output-capture thread */
pthread_mutex_t mutWrite; /* mutex for reopening the output file on HUP while being written */
pthread_mutex_t mutTerm; /* mutex for signaling the termination of the thread */
pthread_cond_t condTerm; /* condition for signaling the termination of the thread */
int bIsRunning; /* is the thread running? (if 0, next fields are uninitialized) */
pthread_t thrdID; /* ID of the output-capture thread */
int fdPipe[2]; /* pipe for capturing the output of the child processes */
int fdFile; /* fd of the output file (-1 if it could not be opened) */
int bFileErr; /* file open error occurred? (to avoid reporting too many errors) */
int bReadErr; /* read error occurred? (to avoid reporting too many errors) */
int bWriteErr; /* write error occurred? (to avoid reporting too many errors) */
} outputCaptureCtx_t;
typedef struct _instanceData {
uchar *szBinary; /* name of external program to call */
char **aParams; /* optional parameters to pass to external program */
int iParams; /* holds the count of parameters if set */
uchar *szTemplateName; /* assigned output template */
int bConfirmMessages; /* does the program provide feedback via stdout? */
long lConfirmTimeout; /* how long to wait for feedback from the program (ms) */
int bReportFailures; /* report failures returned by the program as warning logs? */
int bUseTransactions; /* send begin/end transaction marks to program? */
uchar *szBeginTransactionMark; /* mark message for begin transaction */
uchar *szCommitTransactionMark; /* mark message for commit transaction */
int iHUPForward; /* signal to forward on HUP (or NO_HUP_FORWARD) */
int bSignalOnClose; /* should send SIGTERM to program before closing pipe? */
long lCloseTimeout; /* how long to wait for program to terminate after closing pipe (ms) */
int bKillUnresponsive; /* should send SIGKILL if closeTimeout is reached? */
int bForceSingleInst; /* start only one instance of program, even with multiple workers? */
childProcessCtx_t *pSingleChildCtx; /* child process context when bForceSingleInst=true */
pthread_mutex_t *pSingleChildMut; /* mutex for interacting with single child process */
outputCaptureCtx_t *pOutputCaptureCtx; /* settings and state for the output capture thread */
time_t block_if_err; /* time until which interface error is not to be shown */
} instanceData;
typedef struct wrkrInstanceData {
instanceData *pData;
childProcessCtx_t *pChildCtx; /* child process context (can be equal to pSingleChildCtx) */
} wrkrInstanceData_t;
typedef struct configSettings_s {
uchar *szBinary; /* name of external program to call */
} configSettings_t;
static configSettings_t cs;
/* tables for interfacing with the v6 config system */
/* action (instance) parameters */
static struct cnfparamdescr actpdescr[] = {
{ "binary", eCmdHdlrString, CNFPARAM_REQUIRED },
{ "confirmMessages", eCmdHdlrBinary, 0 },
{ "confirmTimeout", eCmdHdlrInt, 0 },
{ "reportFailures", eCmdHdlrBinary, 0 },
{ "useTransactions", eCmdHdlrBinary, 0 },
{ "beginTransactionMark", eCmdHdlrString, 0 },
{ "commitTransactionMark", eCmdHdlrString, 0 },
{ "forceSingleInstance", eCmdHdlrBinary, 0 },
{ "hup.signal", eCmdHdlrGetWord, 0 },
{ "template", eCmdHdlrGetWord, 0 },
{ "signalOnClose", eCmdHdlrBinary, 0 },
{ "closeTimeout", eCmdHdlrInt, 0 },
{ "killUnresponsive", eCmdHdlrBinary, 0 },
{ "output", eCmdHdlrString, 0 },
{ "fileCreateMode", eCmdHdlrFileCreateMode, 0 }
};
static struct cnfparamblk actpblk =
{ CNFPARAMBLK_VERSION,
sizeof(actpdescr)/sizeof(struct cnfparamdescr),
actpdescr
};
/* execute the external program (must be called in child context after fork).
*/
static __attribute__((noreturn)) void
execBinary(const instanceData *pData, int fdStdin, int fdStdout)
{
int fdOutput, maxFd, fd, sigNum;
struct sigaction sigAct;
sigset_t sigSet;
char errStr[1024];
if(dup2(fdStdin, STDIN_FILENO) == -1) {
goto failed;
}
if(pData->pOutputCaptureCtx != NULL) {
fdOutput = pData->pOutputCaptureCtx->fdPipe[1];
} else {
fdOutput = open("/dev/null", O_WRONLY);
if(fdOutput == -1) {
goto failed;
}
}
if(fdStdout != -1) {
/* confirmMessages enabled: redirect stdout to parent via pipe. After
* this point, anything written to the child's stdout will be treated
* by omprog as initialization feedback (see startChild). This
* includes debug messages (DBGPRINTF) when in debug mode. So we
* cannot use DBGPRINTF from this point on, except for error cases.
*/
if(dup2(fdStdout, STDOUT_FILENO) == -1) {
goto failed;
}
} else {
/* confirmMessages disabled: redirect stdout to file or /dev/null */
if(dup2(fdOutput, STDOUT_FILENO) == -1) {
goto failed;
}
}
/* redirect stderr to file or /dev/null */
if(dup2(fdOutput, STDERR_FILENO) == -1) {
goto failed;
}
/* close the file handles the child process doesn't need (all above STDERR).
* The following way is simple and portable, though not perfect.
* See https://stackoverflow.com/a/918469 for alternatives.
*/
maxFd = sysconf(_SC_OPEN_MAX);
if(maxFd < 0 || maxFd > MAX_FD_TO_CLOSE) {
maxFd = MAX_FD_TO_CLOSE;
}
# ifdef VALGRIND
else { /* don't close valgrind reserved fds, to avoid warnings */
maxFd -= 10;
}
# endif
for(fd = STDERR_FILENO + 1 ; fd <= maxFd ; ++fd) {
close(fd);
}
/* reset signal handlers to default */
memset(&sigAct, 0, sizeof(sigAct));
sigemptyset(&sigAct.sa_mask);
sigAct.sa_handler = SIG_DFL;
for(sigNum = 1 ; sigNum < NSIG ; ++sigNum) {
sigaction(sigNum, &sigAct, NULL);
}
/* we need to block SIGINT, otherwise our program is cancelled when we are
* stopped in debug mode.
*/
sigAct.sa_handler = SIG_IGN;
sigaction(SIGINT, &sigAct, NULL);
sigemptyset(&sigSet);
sigprocmask(SIG_SETMASK, &sigSet, NULL);
alarm(0);
/* finally exec program */
execve((char*)pData->szBinary, pData->aParams, environ);
failed:
/* an error occurred: log it and exit the child process. We use the
* 'syslog' system call to log the error (we cannot use LogMsg/LogError,
* since these functions add directly to the rsyslog input queue).
*/
rs_strerror_r(errno, errStr, sizeof(errStr));
DBGPRINTF("omprog: failed to execute program '%s': %s\n",
pData->szBinary, errStr);
openlog("rsyslogd", 0, LOG_SYSLOG);
syslog(LOG_ERR, "omprog: failed to execute program '%s': %s\n",
pData->szBinary, errStr);
exit(1);
}
/* creates a pipe and starts program, uses pipe as stdin for program.
* rgerhards, 2009-04-01
*/
static rsRetVal
openPipe(instanceData *pData, childProcessCtx_t *pChildCtx)
{
int pipeStdin[2] = { -1, -1 };
int pipeStdout[2] = { -1, -1 };
pid_t cpid;
DEFiRet;
/* open a pipe to send messages to the program */
if(pipe(pipeStdin) == -1) {
ABORT_FINALIZE(RS_RET_ERR_CREAT_PIPE);
}
/* if the 'confirmMessages' setting is enabled, open a pipe to receive
message confirmations from the program */
if(pData->bConfirmMessages && pipe(pipeStdout) == -1) {
ABORT_FINALIZE(RS_RET_ERR_CREAT_PIPE);
}
DBGPRINTF("omprog: executing program '%s' with '%d' parameters\n", pData->szBinary,
pData->iParams);
cpid = fork();
if(cpid == -1) {
ABORT_FINALIZE(RS_RET_ERR_FORK);
}
if(cpid == 0) { /* we are now the child process: execute the program */
/* close the pipe ends that the child doesn't need */
close(pipeStdin[1]);
if(pipeStdout[0] != -1) {
close(pipeStdout[0]);
}
execBinary(pData, pipeStdin[0], pipeStdout[1]);
/* NO CODE HERE - WILL NEVER BE REACHED! */
}
DBGPRINTF("omprog: child has pid %d\n", (int) cpid);
/* close the pipe ends that the parent doesn't need */
close(pipeStdin[0]);
if(pipeStdout[1] != -1) {
close(pipeStdout[1]);
}
pChildCtx->fdPipeOut = pipeStdin[1]; /* we'll send messages to the program via this fd */
pChildCtx->fdPipeIn = pipeStdout[0]; /* we'll receive message confirmations via this fd */
pChildCtx->pid = cpid;
pChildCtx->bIsRunning = 1;
finalize_it:
if(iRet != RS_RET_OK) {
if(pipeStdin[0] != -1) {
close(pipeStdin[0]);
close(pipeStdin[1]);
}
if(pipeStdout[0] != -1) {
close(pipeStdout[0]);
close(pipeStdout[1]);
}
}
RETiRet;
}
static void
waitForChild(instanceData *pData, childProcessCtx_t *pChildCtx)
{
int status;
int ret;
long counter;
counter = pData->lCloseTimeout / 10;
while ((ret = waitpid(pChildCtx->pid, &status, WNOHANG)) == 0 && counter > 0) {
srSleep(0, 10000); /* 0 seconds, 10 milliseconds */
--counter;
}
if (ret == 0) { /* timeout reached */
if (!pData->bKillUnresponsive) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' (pid %ld) did not terminate "
"within timeout (%ld ms); ignoring it", pData->szBinary,
(long) pChildCtx->pid, pData->lCloseTimeout);
return;
}
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' (pid %ld) did not terminate "
"within timeout (%ld ms); killing it", pData->szBinary, (long) pChildCtx->pid,
pData->lCloseTimeout);
if (kill(pChildCtx->pid, SIGKILL) == -1) {
LogError(errno, RS_RET_SYS_ERR, "omprog: could not send SIGKILL to child process");
return;
}
ret = waitpid(pChildCtx->pid, &status, 0);
}
/* waitpid will fail with errno == ECHILD if the child process has already
been reaped by the rsyslogd main loop (see rsyslogd.c) */
if(ret == pChildCtx->pid) {
glblReportChildProcessExit(runConf, pData->szBinary, pChildCtx->pid, status);
}
}
/* close pipe and wait for child to terminate
*/
static void
cleanupChild(instanceData *pData, childProcessCtx_t *pChildCtx)
{
assert(pChildCtx->bIsRunning);
if(pChildCtx->fdPipeIn != -1) {
close(pChildCtx->fdPipeIn);
pChildCtx->fdPipeIn = -1;
}
if(pChildCtx->fdPipeOut != -1) {
close(pChildCtx->fdPipeOut);
pChildCtx->fdPipeOut = -1;
}
/* wait for the child AFTER closing the pipe, so it receives EOF */
waitForChild(pData, pChildCtx);
pChildCtx->bIsRunning = 0;
}
/* Send SIGTERM to child process if configured to do so, close pipe
* and wait for child to terminate.
*/
static void
terminateChild(instanceData *pData, childProcessCtx_t *pChildCtx)
{
DBGPRINTF("terminateChild called\n");
assert(pChildCtx->bIsRunning);
if (pData->bSignalOnClose) {
kill(pChildCtx->pid, SIGTERM);
}
cleanupChild(pData, pChildCtx);
}
/* write message to pipe
* note that we do not try to run block-free. If the user fears something
* may block (and this is not acceptable), the action should be run on its
* own action queue.
*/
static rsRetVal
sendMessage(instanceData *pData, childProcessCtx_t *pChildCtx, const uchar *szMsg)
{
ssize_t written;
size_t offset = 0;
DEFiRet;
const size_t len = strlen((char*)szMsg);
do {
written = write(pChildCtx->fdPipeOut, ((char*)szMsg) + offset, len - offset);
if(written == -1) {
if(errno == EINTR) {
continue; /* call interrupted: retry write */
}
if(errno == EPIPE) {
LogMsg(0, RS_RET_ERR_WRITE_PIPE, LOG_WARNING,
"omprog: program '%s' (pid %ld) terminated; will be restarted",
pData->szBinary, (long) pChildCtx->pid);
cleanupChild(pData, pChildCtx); /* force restart in tryResume() */
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
LogError(errno, RS_RET_ERR_WRITE_PIPE, "omprog: error sending message to program");
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
offset += written;
} while(offset < len);
finalize_it:
RETiRet;
}
static rsRetVal
lineToStatusCode(instanceData *pData, const char* line)
{
DEFiRet;
/* strip leading dots (.) from the line, so the program can use them as a keep-alive mechanism */
while(line[0] == '.') {
++line;
}
if(strcmp(line, "OK") == 0) {
iRet = RS_RET_OK;
} else if(strcmp(line, "DEFER_COMMIT") == 0) {
iRet = RS_RET_DEFER_COMMIT;
} else if(strcmp(line, "PREVIOUS_COMMITTED") == 0) {
iRet = RS_RET_PREVIOUS_COMMITTED;
} else {
/* anything else is considered a recoverable error */
DBGPRINTF("omprog: program '%s' returned: %s\n", pData->szBinary, line);
if(pData->bReportFailures) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' returned: %s",
pData->szBinary, line);
}
iRet = RS_RET_SUSPENDED;
}
RETiRet;
}
static rsRetVal
readStatus(instanceData *pData, childProcessCtx_t *pChildCtx)
{
struct pollfd fdToPoll[1];
int numReady;
char lineBuf[RESPONSE_LINE_BUFFER_SIZE];
ssize_t lenRead;
size_t offset = 0;
int lineEnded = 0;
DEFiRet;
fdToPoll[0].fd = pChildCtx->fdPipeIn;
fdToPoll[0].events = POLLIN;
do {
numReady = poll(fdToPoll, 1, pData->lConfirmTimeout);
if(numReady == -1) {
if(errno == EINTR) {
continue; /* call interrupted: retry poll */
}
LogError(errno, RS_RET_SYS_ERR, "omprog: error polling for response from program");
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
if(numReady == 0) { /* timeout reached */
LogMsg(0, RS_RET_TIMED_OUT, LOG_WARNING, "omprog: program '%s' (pid %ld) did not respond "
"within timeout (%ld ms); will be restarted", pData->szBinary,
(long) pChildCtx->pid, pData->lConfirmTimeout);
terminateChild(pData, pChildCtx);
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
lenRead = read(pChildCtx->fdPipeIn, lineBuf + offset, sizeof(lineBuf) - offset - 1);
if(lenRead == -1) {
if(errno == EINTR) {
continue; /* call interrupted: retry poll + read */
}
LogError(errno, RS_RET_READ_ERR, "omprog: error reading response from program");
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
if(lenRead == 0) {
LogMsg(0, RS_RET_READ_ERR, LOG_WARNING, "omprog: program '%s' (pid %ld) terminated; "
"will be restarted", pData->szBinary, (long) pChildCtx->pid);
cleanupChild(pData, pChildCtx);
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
offset += lenRead;
lineBuf[offset] = '\0';
lineEnded = (lineBuf[offset-1] == '\n');
/* check that the program has not returned multiple lines. This should not occur if
* the program honors the specified interface. Otherwise, we force a restart of the
* program, since we have probably lost synchronism with it.
*/
if(!lineEnded && strchr(lineBuf + offset - lenRead, '\n') != NULL) {
DBGPRINTF("omprog: program '%s' returned: %s\n", pData->szBinary, lineBuf);
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' returned a multiline response; "
"will be restarted", pData->szBinary);
if(pData->bReportFailures) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' returned: %s",
pData->szBinary, lineBuf);
}
terminateChild(pData, pChildCtx);
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
} while(!lineEnded && offset < sizeof(lineBuf) - 1);
if(!lineEnded) {
DBGPRINTF("omprog: program '%s' returned: %s\n", pData->szBinary, lineBuf);
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' returned a too long response; "
"will be restarted", pData->szBinary);
if(pData->bReportFailures) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: program '%s' returned: %s",
pData->szBinary, lineBuf);
}
terminateChild(pData, pChildCtx);
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
lineBuf[offset-1] = '\0'; /* strip newline char */
/* NOTE: coverity does not like CHKiRet() if it is the last thing before finalize_it.
* Reason is that the if() inside that macro than does not lead to different code paths.
*/
iRet = lineToStatusCode(pData, lineBuf);
finalize_it:
RETiRet;
}
static rsRetVal
allocChildCtx(childProcessCtx_t **ppChildCtx)
{
childProcessCtx_t *pChildCtx;
DEFiRet;
CHKmalloc(pChildCtx = calloc(1, sizeof(childProcessCtx_t)));
*ppChildCtx = pChildCtx;
pChildCtx->bIsRunning = 0;
pChildCtx->pid = -1;
pChildCtx->fdPipeOut = -1;
pChildCtx->fdPipeIn = -1;
finalize_it:
RETiRet;
}
static rsRetVal
startChild(instanceData *pData, childProcessCtx_t *pChildCtx)
{
DEFiRet;
assert(!pChildCtx->bIsRunning);
CHKiRet(openPipe(pData, pChildCtx));
if(pData->bConfirmMessages) {
/* wait for program to confirm successful initialization */
CHKiRet(readStatus(pData, pChildCtx));
}
finalize_it:
if(iRet != RS_RET_OK && pChildCtx->bIsRunning) {
/* if initialization has failed, terminate program */
terminateChild(pData, pChildCtx);
}
RETiRet;
}
static rsRetVal
startSingleChildOnce(instanceData *pData)
{
DEFiRet;
assert(pData->bForceSingleInst);
CHKiConcCtrl(pthread_mutex_lock(pData->pSingleChildMut));
if(pData->pSingleChildCtx->bIsRunning)
goto finalize_it; /* child process already started: nothing to do */
iRet = startChild(pData, pData->pSingleChildCtx);
finalize_it:
pthread_mutex_unlock(pData->pSingleChildMut);
RETiRet;
}
static void
writeOutputToFile(outputCaptureCtx_t *pCtx, char *buf, ssize_t len)
{
ssize_t written;
ssize_t offset = 0;
assert(pCtx->bIsRunning);
pthread_mutex_lock(&pCtx->mutWrite);
if(pCtx->fdFile == -1) {
if(pCtx->bFileErr) { /* discarding output because file couldn't be opened */
goto done;
}
pCtx->fdFile = open((char*)pCtx->szFileName, O_WRONLY | O_APPEND | O_CREAT,
pCtx->fCreateMode);
if(pCtx->fdFile == -1) {
LogError(errno, RS_RET_NO_FILE_ACCESS, "omprog: error opening output file %s; "
"output from program will be discarded", pCtx->szFileName);
pCtx->bFileErr = 1; /* avoid reporting too many errors */
goto done;
}
}
do {
written = write(pCtx->fdFile, buf + offset, len - offset);
if(written == -1) {
if(errno == EINTR) {
continue; /* call interrupted: retry write */
}
if(!pCtx->bWriteErr) {
LogError(errno, RS_RET_SYS_ERR, "omprog: error writing to output file "
"(subsequent errors will not be reported)");
pCtx->bWriteErr = 1; /* avoid reporting too many errors */
}
break;
}
if(pCtx->bWriteErr) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: resumed writing to output file");
pCtx->bWriteErr = 0;
}
offset += written;
} while(offset < len);
done:
pthread_mutex_unlock(&pCtx->mutWrite);
}
static void
closeOutputFile(outputCaptureCtx_t *pCtx)
{
DBGPRINTF("omprog: reopening output file upon reception of HUP signal\n");
pthread_mutex_lock(&pCtx->mutWrite);
if(pCtx->fdFile != -1) {
close(pCtx->fdFile);
pCtx->fdFile = -1;
}
pCtx->bFileErr = 0; /* if there was an error opening the file, we'll retry */
pthread_mutex_unlock(&pCtx->mutWrite);
}
/* This code runs in a dedicated thread. Captures the output of the child processes
* through a shared pipe (one reader and multiple writers), and writes the output
* to a file. The lines concurrently emmitted to stdout/stderr by the child processes
* will not appear intermingled in the output file if 1) the lines are short enough
* (less than PIPE_BUF bytes long: 4KB on Linux, and 512 bytes or more on other
* POSIX systems), and 2) the program outputs each line using a single 'write'
* syscall (line buffering mode). When a HUP signal is received, the output file is
* reopened (this provides support for external rotation of the file).
*/
static void *
captureOutput(void *_pCtx) {
outputCaptureCtx_t *pCtx = (outputCaptureCtx_t *)_pCtx;
sigset_t sigSet;
char readBuf[OUTPUT_CAPTURE_BUFFER_SIZE];
ssize_t lenRead;
DBGPRINTF("omprog: starting output capture thread\n");
/* block signals for this thread (otherwise shutdown hangs on FreeBSD) */
sigfillset(&sigSet);
pthread_sigmask(SIG_SETMASK, &sigSet, NULL);
for(;;) {
lenRead = read(pCtx->fdPipe[0], readBuf, sizeof(readBuf));
if(lenRead == -1) {
if(errno == EINTR) {
continue; /* call interrupted: retry read */
}
if(!pCtx->bReadErr) {
LogError(errno, RS_RET_SYS_ERR, "omprog: error capturing output from program "
"(subsequent errors will not be reported)");
pCtx->bReadErr = 1; /* avoid reporting too many errors */
}
continue; /* continue with next line */
}
if(lenRead == 0) {
break; /* all write ends of pipe closed: exit loop and terminate thread */
}
if(pCtx->bReadErr) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: resumed capturing output from program");
pCtx->bReadErr = 0;
}
writeOutputToFile(pCtx, readBuf, lenRead);
}
DBGPRINTF("omprog: all output-capture pipe ends closed, terminating output capture thread\n");
pthread_mutex_lock(&pCtx->mutTerm);
pCtx->bIsRunning = 0;
pthread_cond_signal(&pCtx->condTerm);
pthread_mutex_unlock(&pCtx->mutTerm);
return NULL;
}
static rsRetVal
allocOutputCaptureCtx(outputCaptureCtx_t **ppCtx)
{
outputCaptureCtx_t *pCtx;
DEFiRet;
CHKmalloc(pCtx = calloc(1, sizeof(outputCaptureCtx_t)));
*ppCtx = pCtx;
pCtx->szFileName = NULL;
pCtx->fCreateMode = 0600;
pCtx->bIsRunning = 0;
CHKiConcCtrl(pthread_mutex_init(&pCtx->mutStart, NULL));
CHKiConcCtrl(pthread_mutex_init(&pCtx->mutWrite, NULL));
CHKiConcCtrl(pthread_mutex_init(&pCtx->mutTerm, NULL));
CHKiConcCtrl(pthread_cond_init(&pCtx->condTerm, NULL));
finalize_it:
RETiRet;
}
static void
freeOutputCaptureCtx(outputCaptureCtx_t *pCtx) {
if(pCtx->szFileName != NULL) {
free(pCtx->szFileName);
}
pthread_cond_destroy(&pCtx->condTerm);
pthread_mutex_destroy(&pCtx->mutTerm);
pthread_mutex_destroy(&pCtx->mutWrite);
pthread_mutex_destroy(&pCtx->mutStart);
free(pCtx);
}
static rsRetVal
startOutputCaptureOnce(outputCaptureCtx_t *pCtx)
{
int pip[2] = { -1, -1 };
DEFiRet;
CHKiConcCtrl(pthread_mutex_lock(&pCtx->mutStart));
if(pCtx->bIsRunning)
goto finalize_it; /* output capture thread already started: nothing to do */
/* open a (single) pipe to capture output from (all) child processes */
if(pipe(pip) == -1) {
ABORT_FINALIZE(RS_RET_ERR_CREAT_PIPE);
}
pCtx->fdPipe[0] = pip[0];
pCtx->fdPipe[1] = pip[1];
pCtx->fdFile = -1;
pCtx->bFileErr = 0;
pCtx->bReadErr = 0;
pCtx->bWriteErr = 0;
/* start a thread to read lines from the pipe and write them to the output file */
CHKiConcCtrl(pthread_create(&pCtx->thrdID, NULL, captureOutput, (void *)pCtx));
pCtx->bIsRunning = 1;
finalize_it:
if(iRet != RS_RET_OK && pip[0] != -1) {
close(pip[0]);
close(pip[1]);
}
pthread_mutex_unlock(&pCtx->mutStart);
RETiRet;
}
static void
endOutputCapture(outputCaptureCtx_t *pCtx, long timeoutMs)
{
struct timespec ts;
int bTimedOut;
assert(pCtx->bIsRunning);
/* close our write end of the output-capture pipe */
close(pCtx->fdPipe[1]);
/* the output capture thread will now terminate because there are no more
* writers attached to the output-capture pipe. However, if a child becomes
* unresponsive without closing its pipe end (assuming killUnresponsive=off),
* we would wait forever. To avoid this, we wait for the thread to terminate
* during a maximum timeout (we reuse the 'closeTimeout' setting for this).
*/
timeoutComp(&ts, timeoutMs);
pthread_mutex_lock(&pCtx->mutTerm);
bTimedOut = 0;
while(pCtx->bIsRunning && !bTimedOut) {
if(pthread_cond_timedwait(&pCtx->condTerm, &pCtx->mutTerm, &ts) == ETIMEDOUT) {
bTimedOut = 1;
}
}
pthread_mutex_unlock(&pCtx->mutTerm);
if(bTimedOut) {
LogMsg(0, NO_ERRCODE, LOG_WARNING, "omprog: forcing termination of output capture "
"thread because of unresponsive child process");
pthread_cancel(pCtx->thrdID);
pCtx->bIsRunning = 0;
}
pthread_join(pCtx->thrdID, NULL);
/* close the read end of the output-capture pipe */
close(pCtx->fdPipe[0]);
/* close the output file (if it could be opened) */
if(pCtx->fdFile != -1) {
close(pCtx->fdFile);
}
}
BEGINinitConfVars /* (re)set config variables to default values */
CODESTARTinitConfVars
cs.szBinary = NULL; /* name of binary to call */
ENDinitConfVars
BEGINcreateInstance
CODESTARTcreateInstance
pData->szBinary = NULL;
pData->szTemplateName = NULL;
pData->aParams = NULL;
pData->iParams = 0;
pData->bConfirmMessages = 0;
pData->block_if_err = 0;
pData->lConfirmTimeout = DEFAULT_CONFIRM_TIMEOUT_MS;
pData->bReportFailures = 0;
pData->bUseTransactions = 0;
pData->szBeginTransactionMark = NULL;
pData->szCommitTransactionMark = NULL;
pData->iHUPForward = NO_HUP_FORWARD;
pData->bSignalOnClose = 0;
pData->lCloseTimeout = DEFAULT_CLOSE_TIMEOUT_MS;
pData->bKillUnresponsive = -1;
pData->bForceSingleInst = 0;
pData->pSingleChildCtx = NULL;
pData->pSingleChildMut = NULL;
pData->pOutputCaptureCtx = NULL;
ENDcreateInstance
static rsRetVal
postInitInstance(instanceData *pData)
{
DEFiRet;
if(pData->bUseTransactions && pData->szBeginTransactionMark == NULL) {
pData->szBeginTransactionMark = (uchar*)strdup("BEGIN TRANSACTION");
}
if(pData->bUseTransactions && pData->szCommitTransactionMark == NULL) {
pData->szCommitTransactionMark = (uchar*)strdup("COMMIT TRANSACTION");
}
if(pData->bKillUnresponsive == -1) { /* default value: bSignalOnClose */
pData->bKillUnresponsive = pData->bSignalOnClose;
}
if(pData->pOutputCaptureCtx != NULL && pData->pOutputCaptureCtx->szFileName == NULL) {
LogError(0, RS_RET_CONF_PARAM_INVLD, "omprog: the 'fileCreateMode' parameter requires "
"specifying the 'output' parameter also");
ABORT_FINALIZE(RS_RET_CONF_PARAM_INVLD);
}
if(pData->bForceSingleInst) {
CHKmalloc(pData->pSingleChildMut = calloc(1, sizeof(pthread_mutex_t)));
CHKiConcCtrl(pthread_mutex_init(pData->pSingleChildMut, NULL));
CHKiRet(allocChildCtx(&pData->pSingleChildCtx));
/* do not start the child here. The config is still being parsed, and the daemon
has not been forked yet. When the daemon is forked, all fds will be closed! */
}
finalize_it:
/* no cleanup needed on error: newActInst() will call freeInstance() */
RETiRet;
}
BEGINcreateWrkrInstance
CODESTARTcreateWrkrInstance
pWrkrData->pChildCtx = NULL;
if(pWrkrData->pData->pOutputCaptureCtx != NULL) {
CHKiRet(startOutputCaptureOnce(pWrkrData->pData->pOutputCaptureCtx));
}
if(pWrkrData->pData->bForceSingleInst) {
CHKiRet(startSingleChildOnce(pWrkrData->pData));
pWrkrData->pChildCtx = pData->pSingleChildCtx;
} else {
CHKiRet(allocChildCtx(&pWrkrData->pChildCtx));
CHKiRet(startChild(pWrkrData->pData, pWrkrData->pChildCtx));
}
finalize_it:
ENDcreateWrkrInstance
BEGINisCompatibleWithFeature
CODESTARTisCompatibleWithFeature
if(eFeat == sFEATURERepeatedMsgReduction) {
iRet = RS_RET_OK;
}
ENDisCompatibleWithFeature
BEGINdbgPrintInstInfo
CODESTARTdbgPrintInstInfo
ENDdbgPrintInstInfo
BEGINtryResume
CODESTARTtryResume
if(pWrkrData->pData->bForceSingleInst) {
CHKiConcCtrl(pthread_mutex_lock(pWrkrData->pData->pSingleChildMut));
}
if(!pWrkrData->pChildCtx->bIsRunning) {
CHKiRet(startChild(pWrkrData->pData, pWrkrData->pChildCtx));
}
finalize_it:
if(pWrkrData->pData->bForceSingleInst) {
pthread_mutex_unlock(pWrkrData->pData->pSingleChildMut);
}
ENDtryResume
BEGINbeginTransaction
CODESTARTbeginTransaction
if(pWrkrData->pData->bForceSingleInst) {
CHKiConcCtrl(pthread_mutex_lock(pWrkrData->pData->pSingleChildMut));
}
if(!pWrkrData->pData->bUseTransactions) {
FINALIZE;
}
CHKiRet(sendMessage(pWrkrData->pData, pWrkrData->pChildCtx,
pWrkrData->pData->szBeginTransactionMark));
CHKiRet(sendMessage(pWrkrData->pData, pWrkrData->pChildCtx, (uchar*) "\n"));
if(pWrkrData->pData->bConfirmMessages) {
CHKiRet(readStatus(pWrkrData->pData, pWrkrData->pChildCtx));
}
finalize_it:
if(pWrkrData->pData->bForceSingleInst) {
pthread_mutex_unlock(pWrkrData->pData->pSingleChildMut);
}
ENDbeginTransaction
BEGINdoAction
CODESTARTdoAction
if(pWrkrData->pData->bForceSingleInst) {
CHKiConcCtrl(pthread_mutex_lock(pWrkrData->pData->pSingleChildMut));
}
if(!pWrkrData->pChildCtx->bIsRunning) { /* should not occur */
ABORT_FINALIZE(RS_RET_SUSPENDED);
}
const uchar *const szMsg = ppString[0];
const size_t len = strlen((char*)szMsg);
CHKiRet(sendMessage(pWrkrData->pData, pWrkrData->pChildCtx, szMsg));
if(szMsg[len-1] != '\n') {