ctdb/server/ctdb_logging.c

   1 /*
   2    ctdb logging code
   3
   4    Copyright (C) Andrew Tridgell  2008
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "../include/ctdb_client.h"
  22 #include "../include/ctdb_private.h"
  23 #include "system/syslog.h"
  24 #include "system/time.h"
  25 #include "system/filesys.h"
  26 #include "lib/util/debug.h"
  27
  28 struct syslog_message {
  29         uint32_t level;
  30         uint32_t len;
  31         char message[1];
  32 };
  33
  34
  35 struct ctdb_syslog_state {
  36         int syslog_fd;
  37         int fd[2];
  38 };
  39
  40 static int syslogd_is_started = 0;
  41
  42 /* called when child is finished
  43  * this is for the syslog daemon, we can not use DEBUG here
  44  */
  45 static void ctdb_syslog_handler(struct event_context *ev, struct fd_event *fde,
  46                                       uint16_t flags, void *p)
  47 {
  48         struct ctdb_syslog_state *state = talloc_get_type(p, struct ctdb_syslog_state);
  49
  50         int count;
  51         char str[65536];
  52         struct syslog_message *msg;
  53
  54         if (state == NULL) {
  55                 return;
  56         }
  57
  58         count = recv(state->syslog_fd, str, sizeof(str), 0);
  59         if (count < sizeof(struct syslog_message)) {
  60                 return;
  61         }
  62         msg = (struct syslog_message *)str;
  63         if (msg->len >= (sizeof(str) - offsetof(struct syslog_message, message))) {
  64                 msg->len = (sizeof(str)-1) - offsetof(struct syslog_message, message);
  65         }
  66         msg->message[msg->len] = '\0';
  67
  68         syslog(msg->level, "%s", msg->message);
  69 }
  70
  71
  72 /* called when the pipe from the main daemon has closed
  73  * this is for the syslog daemon, we can not use DEBUG here
  74  */
  75 static void ctdb_syslog_terminate_handler(struct event_context *ev, struct fd_event *fde,
  76                                       uint16_t flags, void *p)
  77 {
  78         syslog(LOG_ERR, "Shutting down SYSLOG daemon with pid:%d", (int)getpid());
  79         _exit(0);
  80 }
  81
  82
  83
  84 /*
  85  * this is for the syslog daemon, we can not use DEBUG here
  86  */
  87 int start_syslog_daemon(struct ctdb_context *ctdb)
  88 {
  89         struct sockaddr_in syslog_sin;
  90         struct ctdb_syslog_state *state;
  91         struct tevent_fd *fde;
  92         int startup_fd[2];
  93         int ret = -1;
  94
  95         state = talloc(ctdb, struct ctdb_syslog_state);
  96         CTDB_NO_MEMORY(ctdb, state);
  97
  98         if (pipe(state->fd) != 0) {
  99                 printf("Failed to create syslog pipe\n");
 100                 talloc_free(state);
 101                 return -1;
 102         }
 103
 104         if (pipe(startup_fd) != 0) {
 105                 printf("Failed to create syslog startup pipe\n");
 106                 close(state->fd[0]);
 107                 close(state->fd[1]);
 108                 talloc_free(state);
 109                 return -1;
 110         }
 111
 112         ctdb->syslogd_pid = ctdb_fork(ctdb);
 113         if (ctdb->syslogd_pid == (pid_t)-1) {
 114                 printf("Failed to create syslog child process\n");
 115                 close(state->fd[0]);
 116                 close(state->fd[1]);
 117                 close(startup_fd[0]);
 118                 close(startup_fd[1]);
 119                 talloc_free(state);
 120                 return -1;
 121         }
 122
 123         if (ctdb->syslogd_pid != 0) {
 124                 ssize_t n;
 125                 int dummy;
 126
 127                 DEBUG(DEBUG_ERR,("Starting SYSLOG child process with pid:%d\n", (int)ctdb->syslogd_pid));
 128
 129                 close(state->fd[1]);
 130                 set_close_on_exec(state->fd[0]);
 131
 132                 close(startup_fd[1]);
 133                 n = sys_read(startup_fd[0], &dummy, sizeof(dummy));
 134                 close(startup_fd[0]);
 135                 if (n < sizeof(dummy)) {
 136                         return -1;
 137                 }
 138
 139                 syslogd_is_started = 1;
 140                 return 0;
 141         }
 142
 143         debug_extra = talloc_asprintf(NULL, "syslogd:");
 144         talloc_free(ctdb->ev);
 145         ctdb->ev = event_context_init(NULL);
 146
 147         syslog(LOG_ERR, "Starting SYSLOG daemon with pid:%d", (int)getpid());
 148         ctdb_set_process_name("ctdb_syslogd");
 149
 150         close(state->fd[0]);
 151         close(startup_fd[0]);
 152         set_close_on_exec(state->fd[1]);
 153         set_close_on_exec(startup_fd[1]);
 154         fde = event_add_fd(ctdb->ev, state, state->fd[1], EVENT_FD_READ,
 155                      ctdb_syslog_terminate_handler, state);
 156         tevent_fd_set_auto_close(fde);
 157
 158         state->syslog_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 159         if (state->syslog_fd == -1) {
 160                 printf("Failed to create syslog socket\n");
 161                 close(startup_fd[1]);
 162                 return ret;
 163         }
 164
 165         set_close_on_exec(state->syslog_fd);
 166
 167         syslog_sin.sin_family = AF_INET;
 168         syslog_sin.sin_port   = htons(CTDB_PORT);
 169         syslog_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 170
 171         if (bind(state->syslog_fd, (struct sockaddr *)&syslog_sin,
 172                  sizeof(syslog_sin)) == -1)
 173         {
 174                 printf("syslog daemon failed to bind to socket. errno:%d(%s)\n", errno, strerror(errno));
 175                 close(startup_fd[1]);
 176                 _exit(10);
 177         }
 178
 179
 180         fde = event_add_fd(ctdb->ev, state, state->syslog_fd, EVENT_FD_READ,
 181                      ctdb_syslog_handler, state);
 182         tevent_fd_set_auto_close(fde);
 183
 184         /* Tell parent that we're up */
 185         ret = 0;
 186         sys_write(startup_fd[1], &ret, sizeof(ret));
 187         close(startup_fd[1]);
 188
 189         event_loop_wait(ctdb->ev);
 190
 191         /* this should not happen */
 192         _exit(10);
 193 }
 194
 195 struct ctdb_log_state {
 196         struct ctdb_context *ctdb;
 197         const char *prefix;
 198         int fd, pfd;
 199         char buf[1024];
 200         uint16_t buf_used;
 201         bool use_syslog;
 202         void (*logfn)(const char *, uint16_t, void *);
 203         void *logfn_private;
 204 };
 205
 206 /* we need this global to keep the DEBUG() syntax */
 207 static struct ctdb_log_state *log_state;
 208
 209 /*
 210   syslog logging function
 211  */
 212 static void ctdb_syslog_log(void *private_ptr, int dbglevel, const char *s)
 213 {
 214         struct syslog_message *msg;
 215         int level = LOG_DEBUG;
 216         int len;
 217         int syslog_fd;
 218         struct sockaddr_in syslog_sin;
 219
 220         switch (dbglevel) {
 221         case DEBUG_ERR:
 222                 level = LOG_ERR;
 223                 break;
 224         case DEBUG_WARNING:
 225                 level = LOG_WARNING;
 226                 break;
 227         case DEBUG_NOTICE:
 228                 level = LOG_NOTICE;
 229                 break;
 230         case DEBUG_INFO:
 231                 level = LOG_INFO;
 232                 break;
 233         default:
 234                 level = LOG_DEBUG;
 235                 break;
 236         }
 237
 238         len = offsetof(struct syslog_message, message) + strlen(debug_extra) + strlen(s) + 1;
 239         msg = malloc(len);
 240         if (msg == NULL) {
 241                 return;
 242         }
 243         msg->level = level;
 244         msg->len   = strlen(debug_extra) + strlen(s);
 245         strcpy(msg->message, debug_extra);
 246         strcat(msg->message, s);
 247
 248         if (syslogd_is_started == 0) {
 249                 syslog(msg->level, "%s", msg->message);
 250         } else {
 251                 syslog_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 252                 if (syslog_fd == -1) {
 253                         printf("Failed to create syslog socket\n");
 254                         free(msg);
 255                         return;
 256                 }
 257
 258                 syslog_sin.sin_family = AF_INET;
 259                 syslog_sin.sin_port   = htons(CTDB_PORT);
 260                 syslog_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 261
 262                 (void) sendto(syslog_fd, msg, len, 0,
 263                               (struct sockaddr *)&syslog_sin,
 264                               sizeof(syslog_sin));
 265                 /* no point in checking here since we cant log an error */
 266
 267                 close(syslog_fd);
 268         }
 269
 270         free(msg);
 271 }
 272
 273
 274 /*
 275   log file logging function
 276  */
 277 static void ctdb_logfile_log(void *private_ptr, int dbglevel, const char *s)
 278 {
 279         struct timeval t;
 280         struct tm *tm;
 281         char tbuf[100];
 282         char *s2 = NULL;
 283         int ret;
 284
 285         t = timeval_current();
 286         tm = localtime(&t.tv_sec);
 287
 288         strftime(tbuf,sizeof(tbuf)-1,"%Y/%m/%d %H:%M:%S", tm);
 289
 290         ret = asprintf(&s2, "%s.%06u [%s%5u]: %s\n",
 291                        tbuf, (unsigned)t.tv_usec,
 292                        debug_extra, (unsigned)getpid(), s);
 293         if (ret == -1) {
 294                 const char *errstr = "asprintf failed\n";
 295                 sys_write(log_state->fd, errstr, strlen(errstr));
 296                 return;
 297         }
 298         if (s2) {
 299                 sys_write(log_state->fd, s2, strlen(s2));
 300                 free(s2);
 301         }
 302 }
 303
 304 /*
 305   choose the logfile location
 306 */
 307 int ctdb_set_logfile(struct ctdb_context *ctdb, const char *logfile, bool use_syslog)
 308 {
 309         debug_callback_fn callback;
 310         int ret;
 311
 312         ctdb->log = talloc_zero(ctdb, struct ctdb_log_state);
 313         if (ctdb->log == NULL) {
 314                 printf("talloc_zero failed\n");
 315                 abort();
 316         }
 317
 318         ctdb->log->ctdb = ctdb;
 319         log_state = ctdb->log;
 320
 321         if (use_syslog) {
 322                 callback = ctdb_syslog_log;
 323                 ctdb->log->use_syslog = true;
 324         } else if (logfile == NULL || strcmp(logfile, "-") == 0) {
 325                 callback = ctdb_logfile_log;
 326                 ctdb->log->fd = 1;
 327                 /* also catch stderr of subcommands to stdout */
 328                 ret = dup2(1, 2);
 329                 if (ret == -1) {
 330                         printf("dup2 failed: %s\n", strerror(errno));
 331                         abort();
 332                 }
 333         } else {
 334                 callback = ctdb_logfile_log;
 335
 336                 ctdb->log->fd = open(logfile, O_WRONLY|O_APPEND|O_CREAT, 0666);
 337                 if (ctdb->log->fd == -1) {
 338                         printf("Failed to open logfile %s\n", logfile);
 339                         abort();
 340                 }
 341         }
 342
 343         debug_set_callback(NULL, callback);
 344
 345         return 0;
 346 }
 347
 348 /* Note that do_debug always uses the global log state. */
 349 static void write_to_log(struct ctdb_log_state *log,
 350                          const char *buf, unsigned int len)
 351 {
 352         if (script_log_level <= DEBUGLEVEL) {
 353                 if (log != NULL && log->prefix != NULL) {
 354                         dbgtext("%s: %*.*s\n", log->prefix, len, len, buf);
 355                 } else {
 356                         dbgtext("%*.*s\n", len, len, buf);
 357                 }
 358                 /* log it in the eventsystem as well */
 359                 if (log && log->logfn) {
 360                         log->logfn(log->buf, len, log->logfn_private);
 361                 }
 362         }
 363 }
 364
 365 /*
 366   called when log data comes in from a child process
 367  */
 368 static void ctdb_log_handler(struct event_context *ev, struct fd_event *fde,
 369                              uint16_t flags, void *private)
 370 {
 371         struct ctdb_log_state *log = talloc_get_type(private, struct ctdb_log_state);
 372         char *p;
 373         int n;
 374
 375         if (!(flags & EVENT_FD_READ)) {
 376                 return;
 377         }
 378
 379         n = sys_read(log->pfd, &log->buf[log->buf_used],
 380                  sizeof(log->buf) - log->buf_used);
 381         if (n > 0) {
 382                 log->buf_used += n;
 383         } else if (n == 0) {
 384                 if (log != log_state) {
 385                         talloc_free(log);
 386                 }
 387                 return;
 388         }
 389
 390         while (log->buf_used > 0 &&
 391                (p = memchr(log->buf, '\n', log->buf_used)) != NULL) {
 392                 int n1 = (p - log->buf)+1;
 393                 int n2 = n1 - 1;
 394                 /* swallow \r from child processes */
 395                 if (n2 > 0 && log->buf[n2-1] == '\r') {
 396                         n2--;
 397                 }
 398                 write_to_log(log, log->buf, n2);
 399                 memmove(log->buf, p+1, sizeof(log->buf) - n1);
 400                 log->buf_used -= n1;
 401         }
 402
 403         /* the buffer could have completely filled - unfortunately we have
 404            no choice but to dump it out straight away */
 405         if (log->buf_used == sizeof(log->buf)) {
 406                 write_to_log(log, log->buf, log->buf_used);
 407                 log->buf_used = 0;
 408         }
 409 }
 410
 411 static int log_context_destructor(struct ctdb_log_state *log)
 412 {
 413         /* Flush buffer in case it wasn't \n-terminated. */
 414         if (log->buf_used > 0) {
 415                 write_to_log(log, log->buf, log->buf_used);
 416         }
 417         return 0;
 418 }
 419
 420 /*
 421  * vfork + exec, redirecting child output to logging and specified callback.
 422  */
 423 struct ctdb_log_state *ctdb_vfork_with_logging(TALLOC_CTX *mem_ctx,
 424                                                struct ctdb_context *ctdb,
 425                                                const char *log_prefix,
 426                                                const char *helper,
 427                                                int helper_argc,
 428                                                const char **helper_argv,
 429                                                void (*logfn)(const char *, uint16_t, void *),
 430                                                void *logfn_private, pid_t *pid)
 431 {
 432         int p[2];
 433         struct ctdb_log_state *log;
 434         struct tevent_fd *fde;
 435         char **argv;
 436         int i;
 437
 438         log = talloc_zero(mem_ctx, struct ctdb_log_state);
 439         CTDB_NO_MEMORY_NULL(ctdb, log);
 440
 441         log->ctdb = ctdb;
 442         log->prefix = log_prefix;
 443         log->logfn = logfn;
 444         log->logfn_private = logfn_private;
 445
 446         if (pipe(p) != 0) {
 447                 DEBUG(DEBUG_ERR, (__location__ " Failed to setup pipe for child logging\n"));
 448                 goto free_log;
 449         }
 450
 451         argv = talloc_array(mem_ctx, char *, helper_argc + 2);
 452         if (argv == NULL) {
 453                 DEBUG(DEBUG_ERR, (__location__ "Failed to allocate memory for helper\n"));
 454                 goto free_log;
 455         }
 456         argv[0] = discard_const(helper);
 457         argv[1] = talloc_asprintf(argv, "%d", p[1]);
 458         if (argv[1] == NULL) {
 459                 DEBUG(DEBUG_ERR, (__location__ "Failed to allocate memory for helper\n"));
 460                 talloc_free(argv);
 461                 goto free_log;
 462         }
 463
 464         for (i=0; i<helper_argc; i++) {
 465                 argv[i+2] = discard_const(helper_argv[i]);
 466         }
 467
 468         *pid = vfork();
 469         if (*pid == 0) {
 470                 execv(helper, argv);
 471                 _exit(1);
 472         }
 473         close(p[1]);
 474
 475         if (*pid < 0) {
 476                 DEBUG(DEBUG_ERR, (__location__ "vfork failed for helper process\n"));
 477                 close(p[0]);
 478                 goto free_log;
 479         }
 480
 481         ctdb_track_child(ctdb, *pid);
 482
 483         log->pfd = p[0];
 484         set_close_on_exec(log->pfd);
 485         talloc_set_destructor(log, log_context_destructor);
 486         fde = tevent_add_fd(ctdb->ev, log, log->pfd, EVENT_FD_READ,
 487                             ctdb_log_handler, log);
 488         tevent_fd_set_auto_close(fde);
 489
 490         return log;
 491
 492 free_log:
 493         talloc_free(log);
 494         return NULL;
 495 }
 496
 497
 498 /*
 499   setup for logging of child process stdout
 500 */
 501 int ctdb_set_child_logging(struct ctdb_context *ctdb)
 502 {
 503         int p[2];
 504         int old_stdout, old_stderr;
 505         struct tevent_fd *fde;
 506
 507         if (ctdb->log->fd == STDOUT_FILENO) {
 508                 /* not needed for stdout logging */
 509                 return 0;
 510         }
 511
 512         /* setup a pipe to catch IO from subprocesses */
 513         if (pipe(p) != 0) {
 514                 DEBUG(DEBUG_ERR,(__location__ " Failed to setup for child logging pipe\n"));
 515                 return -1;
 516         }
 517
 518         /* We'll fail if stderr/stdout not already open; it's simpler. */
 519         old_stdout = dup(STDOUT_FILENO);
 520         old_stderr = dup(STDERR_FILENO);
 521         if (old_stdout < 0 || old_stderr < 0) {
 522                 DEBUG(DEBUG_ERR, ("Failed to dup stdout/stderr for child logging\n"));
 523                 return -1;
 524         }
 525         if (dup2(p[1], STDOUT_FILENO) < 0 || dup2(p[1], STDERR_FILENO) < 0) {
 526                 int saved_errno = errno;
 527                 dup2(old_stdout, STDOUT_FILENO);
 528                 dup2(old_stderr, STDERR_FILENO);
 529                 close(old_stdout);
 530                 close(old_stderr);
 531                 close(p[0]);
 532                 close(p[1]);
 533                 errno = saved_errno;
 534
 535                 printf(__location__ " dup2 failed: %s\n",
 536                         strerror(errno));
 537                 return -1;
 538         }
 539         close(p[1]);
 540         close(old_stdout);
 541         close(old_stderr);
 542
 543         fde = event_add_fd(ctdb->ev, ctdb->log, p[0],
 544                            EVENT_FD_READ, ctdb_log_handler, ctdb->log);
 545         tevent_fd_set_auto_close(fde);
 546
 547         ctdb->log->pfd = p[0];
 548
 549         DEBUG(DEBUG_DEBUG, (__location__ " Created PIPE FD:%d for logging\n", p[0]));
 550
 551         return 0;
 552 }
 553
 554
 555 /*
 556  * set up a log handler to catch logging from TEVENT
 557  */
 558 static void ctdb_tevent_logging(void *private_data,
 559                                 enum tevent_debug_level level,
 560                                 const char *fmt,
 561                                 va_list ap)
 562 {
 563         enum debug_level lvl = DEBUG_CRIT;
 564
 565         switch (level) {
 566         case TEVENT_DEBUG_FATAL:
 567                 lvl = DEBUG_CRIT;
 568                 break;
 569         case TEVENT_DEBUG_ERROR:
 570                 lvl = DEBUG_ERR;
 571                 break;
 572         case TEVENT_DEBUG_WARNING:
 573                 lvl = DEBUG_WARNING;
 574                 break;
 575         case TEVENT_DEBUG_TRACE:
 576                 lvl = DEBUG_DEBUG;
 577                 break;
 578         }
 579
 580         if (lvl <= DEBUGLEVEL) {
 581                 dbgtext(fmt, ap);
 582         }
 583 }
 584
 585 int ctdb_init_tevent_logging(struct ctdb_context *ctdb)
 586 {
 587         int ret;
 588
 589         ret = tevent_set_debug(ctdb->ev,
 590                         ctdb_tevent_logging,
 591                         ctdb);
 592         return ret;
 593 }