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
|
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Copyright by The HDF Group. *
* All rights reserved. *
* *
* This file is part of HDF5. The full HDF5 copyright notice, including *
* terms governing use, modification, and redistribution, is contained in *
* the COPYING file, which can be found at the root of the source code *
* distribution tree, or in https://www.hdfgroup.org/licenses. *
* If you do not have access to either file, you may request a copy from *
* help@hdfgroup.org. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*
* "Server" application to associate a Mirror VFD Driver with a Writer.
*
* Server waits on a dedicated port for a Driver to attempt to connect.
* When connection is made, reads a message from the Driver.
* If message is "SHUTDOWN", Server closes connection and terminates.
* Else, if it receives an encoded OPEN xmit (from Driver), the Server forks
* itself; the child becomes a dedicated Writer and maintains connection with
* the Driver instance, and the parent process remains a Server and returns
* to listening for incoming requests.
* Else, the message is not recognized and is ignored.
*
*
*
* mirror_server [args]
*
* Primary server for coordinating mirror VFD connections with the remote
* process.
*
* args:
* --help, -h Print help message and exit.
* --port=N Positive integer for primary listening port.
* --verbosity=N Debugging verbosity
* 0: none
* 1: errors
* 2: details
* 3: all
* --logpath=S File path to direct debugging output, if any.
* Default of none prints output to stdout.
*
*/
#include "mirror_remote.h"
#ifdef H5_HAVE_MIRROR_VFD
#define MAXBUF 2048 /* max buffer length. */
#define LISTENQ 80 /* max pending mirrorS requests */
#define DEFAULT_PORT 3000 /* default listening port */
#define MAX_PORT_LOOPS 20 /* max iteratations through port range */
#define PORT_LOOP_RETRY_DELAY 1 /* seconds to wait between port scans */
/* semi-unique "magic" numbers to sanity-check structure pointers */
#define OP_ARGS_MAGIC 0xCF074379u
#define SERVER_RUN_MAGIC 0x741B459Au
/* ---------------------------------------------------------------------------
* Structure: struct op_args
*
* Purpose: Convenience structure for holding arguments from command-line.
*
* `magic` (uint32_t)
* Semi-unique number to help validate a pointer to this struct type.
* Must be OP_ARGS_MAGIC to be considered valid.
*
* `help` (int)
* Flag that the help argument was present in the command line.
*
* `main_port` (int)
* Flag that the help argument was present in the command line.
*
* `verbosity` (int)
* Number between 0 (none) and 4 (all) that controls how much detail
* the program prints as a course of logging.
*
* `log_prepend_serv` (int)
* Flag that the logging messages should have 'S- ' at the start of each
* line.
*
* `log_prepend_type` (int)
* Flag that the logging messages should have the associated verbosity
* level present in the line (e.g., "WARN", "ERROR", or "INFO").
*
* `log_path` (char *)
* Path string from the command line, giving the absolute path
* for the file for logging output. Can be empty.
*
* `writer_log_path` (char *)
* Path string from the command line, giving the absolute path
* for the file for writer's logging output. Can be empty.
*
* ---------------------------------------------------------------------------
*/
struct op_args {
uint32_t magic;
int help;
int main_port;
unsigned int verbosity;
int log_prepend_serv;
int log_prepend_type;
char log_path[PATH_MAX + 1];
char writer_log_path[PATH_MAX + 1];
};
/* ---------------------------------------------------------------------------
* Structure: struct server_run
*
* Purpose: Convenience structure for holding information about a server
* in operation.
*
* `magic` (uint32_t)
* Semi-unique number to help validate a pointer to this struct type.
* Must be SERVER_RUN_MAGIC to be considered valid.
*
* `log_stream` (FILE *)
* File handle where logging output is directed.
* By default, is stdout.
*
* `opts` (struct opt_args)
* Contained structure, holds the server's configuration.
*
* `listenfd` (int)
* File descriptor of the listening socket.
*
* ---------------------------------------------------------------------------
*/
struct server_run {
uint32_t magic;
struct op_args opts;
struct mirror_log_info *loginfo;
int listenfd;
};
/* ---------------------------------------------------------------------------
* Function: mybzero
*
* Purpose: Introduce bzero without neededing it on the system.
*
* Programmer: Jacob Smith
* 2020-03-30
* ---------------------------------------------------------------------------
*/
static void
mybzero(void *dest, size_t size)
{
size_t i = 0;
char *s = NULL;
HDassert(dest);
s = (char *)dest;
for (i = 0; i < size; i++) {
*(s + i) = 0;
}
} /* end mybzero() */
/* ---------------------------------------------------------------------------
* Function: usage
*
* Purpose: Print the usage message to stdout.
* ---------------------------------------------------------------------------
*/
static void
usage(void)
{
HDfprintf(stdout,
"mirror_server [options]\n"
"\n"
"Application for providing Mirror Writer process to "
" Mirror VFD on file-open.\n"
"Listens on a dedicated socket; forks as a Writer upon receipt"
" of a valid OPEN xmit.\n"
"\n"
"Options:\n"
"--help [-h] : Print this help message and quit.\n"
"--logpath=PATH : File path for logging output "
"(default none, to stdout).\n"
"--port=PORT : Primary port (default %d).\n"
"--verbosity=NUM : Debug printing level "
"0..4, (default %d).\n",
DEFAULT_PORT, MIRROR_LOG_DEFAULT_VERBOSITY);
} /* end usage() */
/* ---------------------------------------------------------------------------
* Function: parse_args
*
* Purpose: Read command line options and store results in args_out
* structure. Fails in event of unrecognized option.
*
* Return: 0 on success, -1 on failure.
* ---------------------------------------------------------------------------
*/
static int
parse_args(int argc, char **argv, struct op_args *args_out)
{
int i;
/* preset default values
*/
args_out->main_port = DEFAULT_PORT;
args_out->help = 0;
args_out->log_prepend_serv = 1;
args_out->log_prepend_type = 1;
args_out->verbosity = MIRROR_LOG_DEFAULT_VERBOSITY;
/* preset empty strings */
mybzero(args_out->log_path, PATH_MAX + 1);
mybzero(args_out->writer_log_path, PATH_MAX + 1);
if (argv == NULL || *argv == NULL) {
mirror_log(NULL, V_ERR, "invalid argv pointer");
return -1;
}
/* Loop over arguments after program name and writer_path */
for (i = 2; i < argc; i++) {
if (!HDstrncmp(argv[i], "-h", 3) || !HDstrncmp(argv[i], "--help", 7)) {
mirror_log(NULL, V_INFO, "found help argument");
args_out->help = 1;
return 0;
} /* end if help */
else if (!HDstrncmp(argv[i], "--port=", 7)) {
mirror_log(NULL, V_INFO, "parsing 'main_port' (%s)", argv[i] + 7);
args_out->main_port = HDatoi(argv[i] + 7);
} /* end if port */
else if (!HDstrncmp(argv[i], "--verbosity=", 12)) {
mirror_log(NULL, V_INFO, "parsing 'verbosity' (%s)", argv[i] + 12);
args_out->verbosity = (unsigned int)HDatoi(argv[i] + 12);
} /* end if verbosity */
else if (!HDstrncmp(argv[i], "--logpath=", 10)) {
mirror_log(NULL, V_INFO, "parsing 'logpath' (%s)", argv[i] + 10);
HDstrncpy(args_out->log_path, argv[i] + 10, PATH_MAX);
} /* end if logpath */
else {
mirror_log(NULL, V_ERR, "unrecognized argument: %s", argv[i]);
return -1;
} /* end if unrecognized argument */
} /* end for each arg after the path to writer "receiver process" */
mirror_log(NULL, V_INFO, "all args parsed");
return 0;
} /* end parse_args() */
/* ---------------------------------------------------------------------------
* Function: prepare_listening_socket
*
* Purpose: Configure and open a socket.
* In event of error, attempts to undo its processes.
*
* Return: Success: non-negative (the file descriptor of the socket)
* Failure: -1
* ---------------------------------------------------------------------------
*/
static int
prepare_listening_socket(struct server_run *run)
{
struct sockaddr_in server_addr;
int _true = 1; /* needed for setsockopt() */
int ret_value = -1;
int ret = 0; /* for checking return value of function calls */
if (run == NULL || run->magic != SERVER_RUN_MAGIC) {
mirror_log(NULL, V_ERR, "invalid server_run pointer");
return -1;
}
mirror_log(run->loginfo, V_INFO, "preparing socket");
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = HDhtonl(INADDR_ANY);
server_addr.sin_port = HDhtons((uint16_t)run->opts.main_port);
mirror_log(run->loginfo, V_INFO, "socket()");
ret_value = HDsocket(AF_INET, SOCK_STREAM, 0);
if (ret_value < 0) {
mirror_log(run->loginfo, V_ERR, "listening socket:%d", ret_value);
goto error;
}
mirror_log(run->loginfo, V_ALL, "setsockopt()");
HDsetsockopt(ret_value, SOL_SOCKET, SO_REUSEADDR, &_true, sizeof(int));
mirror_log(run->loginfo, V_INFO, "bind()");
ret = HDbind(ret_value, (struct sockaddr *)&server_addr, sizeof(server_addr));
if (ret < 0) {
mirror_log(run->loginfo, V_ERR, "bind() %s", HDstrerror(errno));
goto error;
}
mirror_log(run->loginfo, V_INFO, "listen()");
ret = HDlisten(ret_value, LISTENQ);
if (ret < 0) {
mirror_log(run->loginfo, V_ERR, "H5FD server listen:%d", ret);
goto error;
}
return ret_value;
error:
if (ret_value >= 0) {
HDshutdown(ret_value, SHUT_RDWR);
HDclose(ret_value);
}
return -1;
} /* end prepare_listening_socket() */
/* ---------------------------------------------------------------------------
* Function: init_server_run
*
* Purpose: Set up server_run struct with default and specified values.
*
* Return: Zero (0) if successful, -1 if an error occurred.
* ---------------------------------------------------------------------------
*/
static struct server_run *
init_server_run(int argc, char **argv)
{
struct server_run *run;
run = (struct server_run *)HDmalloc(sizeof(struct server_run));
if (run == NULL) {
mirror_log(NULL, V_ERR, "can't allocate server_run struct");
return NULL;
}
run->magic = (uint32_t)SERVER_RUN_MAGIC;
run->opts.magic = (uint32_t)OP_ARGS_MAGIC;
run->listenfd = -1;
if (parse_args(argc, argv, &(run->opts)) < 0) {
mirror_log(NULL, V_ERR, "can't parse arguments");
usage();
goto error;
}
if (run->opts.help) {
usage();
return run; /* early exit */
}
run->loginfo = mirror_log_init(run->opts.log_path, "s- ", run->opts.verbosity);
run->listenfd = prepare_listening_socket(run);
if (run->listenfd < 0) {
mirror_log(NULL, V_ERR, "can't prepare listening socket");
goto error;
}
return run;
error:
if (run != NULL) {
HDfree(run);
}
return NULL;
} /* end init_server_run() */
/* ---------------------------------------------------------------------------
* Function: term_server_run
*
* Purpose: Close opened items in a sever_run and release the pointer.
*
* Return: Zero (0) if successful, -1 if an error occurred.
* ---------------------------------------------------------------------------
*/
static int
term_server_run(struct server_run *run)
{
if (run == NULL || run->magic != SERVER_RUN_MAGIC) {
mirror_log(NULL, V_ERR, "invalid server_run pointer");
return -1;
}
mirror_log(run->loginfo, V_INFO, "shutting down");
if (run->listenfd >= 0) {
HDshutdown(run->listenfd, SHUT_RDWR); /* TODO: error-checking? */
HDclose(run->listenfd); /* TODO: error-checking? */
run->listenfd = -1;
}
if (mirror_log_term(run->loginfo) < 0) {
mirror_log(NULL, V_ERR, "can't close logging stream");
return -1; /* doesn't solve the problem, but informs of error */
}
run->loginfo = NULL;
(run->magic)++;
(run->opts.magic)++;
HDfree(run);
return 0;
} /* end term_server_run() */
/* ---------------------------------------------------------------------------
* Function: accept_connection
*
* Purpose: Main working loop; process requests as they are received.
* Does nothing if the run option help is set.
*
* Return: -1 on error, else a non-negative file descriptor of the socket.
* ---------------------------------------------------------------------------
*/
static int
accept_connection(struct server_run *run)
{
struct sockaddr_in client_addr; /**/
socklen_t clilen; /**/
struct hostent *host_port = NULL; /**/
char *hostaddrp; /**/
int connfd = -1; /* connection file descriptor */
if (run == NULL || run->magic != SERVER_RUN_MAGIC) {
mirror_log(NULL, V_ERR, "invalid server_run pointer");
return -1;
}
/*------------------------------*/
/* accept a connection on a socket */
clilen = sizeof(client_addr);
connfd = HDaccept(run->listenfd, (struct sockaddr *)&client_addr, &clilen);
if (connfd < 0) {
mirror_log(run->loginfo, V_ERR, "accept:%d", connfd);
goto error;
}
mirror_log(run->loginfo, V_INFO, "connection achieved");
/*------------------------------*/
/* get client address information */
host_port = HDgethostbyaddr((const char *)&client_addr.sin_addr.s_addr,
sizeof(client_addr.sin_addr.s_addr), AF_INET);
if (host_port == NULL) {
mirror_log(run->loginfo, V_ERR, "gethostbyaddr()");
goto error;
}
/* function has the string space statically scoped -- OK until next call */
hostaddrp = HDinet_ntoa(client_addr.sin_addr);
/* TODO? proper error-checking */
mirror_log(run->loginfo, V_INFO, "server connected with %s (%s)", host_port->h_name, hostaddrp);
return connfd;
error:
if (connfd >= 0) {
close(connfd);
}
return -1;
} /* end accept_connection() */
/* ---------------------------------------------------------------------------
* Function: wait_for_child
*
* Purpose: Signal handler to reap zombie processes.
* ---------------------------------------------------------------------------
*/
static void
wait_for_child(int H5_ATTR_UNUSED sig)
{
while (HDwaitpid(-1, NULL, WNOHANG) > 0)
;
} /* end wait_for_child() */
/* ---------------------------------------------------------------------------
* Function: handle_requests
*
* Purpose: Main working loop; process requests as they are received.
* Does nothing if the run option `help` is set.
*
* Return: -1 on error, else 0 for successful operation.
* ---------------------------------------------------------------------------
*/
static int
handle_requests(struct server_run *run)
{
int connfd = -1; /**/
char mybuf[H5FD_MIRROR_XMIT_OPEN_SIZE]; /**/
ssize_t ret; /* general-purpose error-checking */
int pid; /* process ID of fork */
struct sigaction sa;
int ret_value = 0;
if (run == NULL || run->magic != SERVER_RUN_MAGIC) {
mirror_log(NULL, V_ERR, "invalid server_run pointer");
return -1;
}
if (run->opts.help) {
return 0;
}
if (run->listenfd < 0) {
mirror_log(NULL, V_ERR, "invalid listening socket");
return -1;
}
/* Set up the signal handler */
sa.sa_handler = wait_for_child;
HDsigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (HDsigaction(SIGCHLD, &sa, NULL) == -1) {
perror("sigaction");
return 1;
}
/* Keep listening for attempts to connect.
*/
while (1) { /* infinite loop, exited via break or goto */
mirror_log(run->loginfo, V_INFO, "server waiting for connections...");
connfd = -1;
connfd = accept_connection(run);
if (connfd < 0) {
mirror_log(run->loginfo, V_ERR, "unable to receive connection");
goto error;
}
/* Read handshake from port connection.
*/
if ((ret = HDread(connfd, &mybuf, H5FD_MIRROR_XMIT_OPEN_SIZE)) < 0) {
mirror_log(run->loginfo, V_ERR, "read:%d", ret);
goto error;
}
mirror_log(run->loginfo, V_INFO, "received %d bytes", ret);
mirror_log(run->loginfo, V_ALL, "```");
mirror_log_bytes(run->loginfo, V_ALL, (size_t)ret, (const unsigned char *)mybuf);
mirror_log(run->loginfo, V_ALL, "```");
/* Respond to handshake message.
*/
if (!HDstrncmp("SHUTDOWN", mybuf, 8)) {
/* Stop operation if told to stop */
mirror_log(run->loginfo, V_INFO, "received SHUTDOWN!", ret);
HDclose(connfd);
connfd = -1;
goto done;
} /* end if explicit "SHUTDOWN" directive */
else if (H5FD_MIRROR_XMIT_OPEN_SIZE == ret) {
H5FD_mirror_xmit_open_t xopen;
mirror_log(run->loginfo, V_INFO, "probable OPEN xmit received");
H5FD_mirror_xmit_decode_open(&xopen, (const unsigned char *)mybuf);
if (FALSE == H5FD_mirror_xmit_is_open(&xopen)) {
mirror_log(run->loginfo, V_WARN, "expected OPEN xmit was malformed");
HDclose(connfd);
continue;
}
mirror_log(run->loginfo, V_INFO, "probable OPEN xmit confirmed");
pid = HDfork();
if (pid < 0) { /* fork error */
mirror_log(run->loginfo, V_ERR, "cannot fork");
goto error;
} /* end if fork error */
else if (pid == 0) { /* child process (writer side of fork) */
mirror_log(run->loginfo, V_INFO, "executing writer");
if (run_writer(connfd, &xopen) < 0) {
HDprintf("can't run writer\n");
}
else {
HDprintf("writer OK\n");
}
HDclose(connfd);
HDexit(EXIT_SUCCESS);
} /* end if writer side of fork */
else { /* parent process (server side of fork) */
mirror_log(run->loginfo, V_INFO, "tidying up from handshake");
HDclose(connfd);
} /* end if server side of fork */
} /* end else-if valid request for service */
else {
/* Ignore unrecognized messages */
HDclose(connfd);
continue;
} /* end else (not a valid message, to be ignored) */
} /* end while listening for new connections */
done:
if (connfd >= 0) {
mirror_log(run->loginfo, V_WARN, "connfd still open upon cleanup");
HDclose(connfd);
}
return ret_value;
error:
if (connfd >= 0) {
HDclose(connfd);
}
return -1;
} /* end handle_requests() */
/* ------------------------------------------------------------------------- */
int
main(int argc, char **argv)
{
struct server_run *run;
run = init_server_run(argc, argv);
if (NULL == run) {
mirror_log(NULL, V_ERR, "can't initialize run");
HDexit(EXIT_FAILURE);
}
if (handle_requests(run) < 0) {
mirror_log(run->loginfo, V_ERR, "problem handling requests");
}
if (term_server_run(run) < 0) {
mirror_log(NULL, V_ERR, "problem closing server run");
HDexit(EXIT_FAILURE);
}
HDexit(EXIT_SUCCESS);
} /* end main() */
#else /* H5_HAVE_MIRROR_VFD */
int
main(void)
{
HDprintf("Mirror VFD was not built -- cannot launch server.\n");
HDexit(EXIT_FAILURE);
}
#endif /* H5_HAVE_MIRROR_VFD */
|