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         const char *prefix;
 197         int fd, pfd;
 198         char buf[1024];
 199         uint16_t buf_used;
 200         bool use_syslog;
 201         void (*logfn)(const char *, uint16_t, void *);
 202         void *logfn_private;
 203 };
 204
 205 /* we need this global to keep the DEBUG() syntax */
 206 static struct ctdb_log_state *log_state;
 207
 208 /*
 209   syslog logging function
 210  */
 211 static void ctdb_syslog_log(void *private_ptr, int dbglevel, const char *s)
 212 {
 213         struct syslog_message *msg;
 214         int level = LOG_DEBUG;
 215         int len;
 216         int syslog_fd;
 217         struct sockaddr_in syslog_sin;
 218
 219         switch (dbglevel) {
 220         case DEBUG_ERR:
 221                 level = LOG_ERR;
 222                 break;
 223         case DEBUG_WARNING:
 224                 level = LOG_WARNING;
 225                 break;
 226         case DEBUG_NOTICE:
 227                 level = LOG_NOTICE;
 228                 break;
 229         case DEBUG_INFO:
 230                 level = LOG_INFO;
 231                 break;
 232         default:
 233                 level = LOG_DEBUG;
 234                 break;
 235         }
 236
 237         len = offsetof(struct syslog_message, message) + strlen(debug_extra) + strlen(s) + 1;
 238         msg = malloc(len);
 239         if (msg == NULL) {
 240                 return;
 241         }
 242         msg->level = level;
 243         msg->len   = strlen(debug_extra) + strlen(s);
 244         strcpy(msg->message, debug_extra);
 245         strcat(msg->message, s);
 246
 247         if (syslogd_is_started == 0) {
 248                 syslog(msg->level, "%s", msg->message);
 249         } else {
 250                 syslog_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 251                 if (syslog_fd == -1) {
 252                         printf("Failed to create syslog socket\n");
 253                         free(msg);
 254                         return;
 255                 }
 256
 257                 syslog_sin.sin_family = AF_INET;
 258                 syslog_sin.sin_port   = htons(CTDB_PORT);
 259                 syslog_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 260
 261                 (void) sendto(syslog_fd, msg, len, 0,
 262                               (struct sockaddr *)&syslog_sin,
 263                               sizeof(syslog_sin));
 264                 /* no point in checking here since we cant log an error */
 265
 266                 close(syslog_fd);
 267         }
 268
 269         free(msg);
 270 }
 271
 272
 273 /*
 274   log file logging function
 275  */
 276 static void ctdb_logfile_log(void *private_ptr, int dbglevel, const char *s)
 277 {
 278         struct timeval t;
 279         struct tm *tm;
 280         char tbuf[100];
 281         char *s2 = NULL;
 282         int ret;
 283
 284         t = timeval_current();
 285         tm = localtime(&t.tv_sec);
 286
 287         strftime(tbuf,sizeof(tbuf)-1,"%Y/%m/%d %H:%M:%S", tm);
 288
 289         ret = asprintf(&s2, "%s.%06u [%s%5u]: %s\n",
 290                        tbuf, (unsigned)t.tv_usec,
 291                        debug_extra, (unsigned)getpid(), s);
 292         if (ret == -1) {
 293                 const char *errstr = "asprintf failed\n";
 294                 sys_write(log_state->fd, errstr, strlen(errstr));
 295                 return;
 296         }
 297         if (s2) {
 298                 sys_write(log_state->fd, s2, strlen(s2));
 299                 free(s2);
 300         }
 301 }
 302
 303 /*
 304   choose the logfile location
 305 */
 306 int ctdb_set_logfile(TALLOC_CTX *mem_ctx, const char *logfile, bool use_syslog)
 307 {
 308         debug_callback_fn callback;
 309         int ret;
 310
 311         log_state = talloc_zero(mem_ctx, struct ctdb_log_state);
 312         if (log_state == NULL) {
 313                 printf("talloc_zero failed\n");
 314                 abort();
 315         }
 316
 317         if (use_syslog) {
 318                 callback = ctdb_syslog_log;
 319                 log_state->use_syslog = true;
 320         } else if (logfile == NULL || strcmp(logfile, "-") == 0) {
 321                 callback = ctdb_logfile_log;
 322                 log_state->fd = 1;
 323                 /* also catch stderr of subcommands to stdout */
 324                 ret = dup2(1, 2);
 325                 if (ret == -1) {
 326                         printf("dup2 failed: %s\n", strerror(errno));
 327                         abort();
 328                 }
 329         } else {
 330                 callback = ctdb_logfile_log;
 331
 332                 log_state->fd = open(logfile, O_WRONLY|O_APPEND|O_CREAT, 0666);
 333                 if (log_state->fd == -1) {
 334                         printf("Failed to open logfile %s\n", logfile);
 335                         abort();
 336                 }
 337         }
 338
 339         debug_set_callback(NULL, callback);
 340
 341         return 0;
 342 }
 343
 344 /* Note that do_debug always uses the global log state. */
 345 static void write_to_log(struct ctdb_log_state *log,
 346                          const char *buf, unsigned int len)
 347 {
 348         if (script_log_level <= DEBUGLEVEL) {
 349                 if (log != NULL && log->prefix != NULL) {
 350                         dbgtext("%s: %*.*s\n", log->prefix, len, len, buf);
 351                 } else {
 352                         dbgtext("%*.*s\n", len, len, buf);
 353                 }
 354                 /* log it in the eventsystem as well */
 355                 if (log && log->logfn) {
 356                         log->logfn(log->buf, len, log->logfn_private);
 357                 }
 358         }
 359 }
 360
 361 /*
 362   called when log data comes in from a child process
 363  */
 364 static void ctdb_child_log_handler(struct event_context *ev,
 365                                    struct fd_event *fde,
 366                                    uint16_t flags, void *private)
 367 {
 368         struct ctdb_log_state *log = talloc_get_type(private, struct ctdb_log_state);
 369         char *p;
 370         int n;
 371
 372         if (!(flags & EVENT_FD_READ)) {
 373                 return;
 374         }
 375
 376         n = sys_read(log->pfd, &log->buf[log->buf_used],
 377                  sizeof(log->buf) - log->buf_used);
 378         if (n > 0) {
 379                 log->buf_used += n;
 380         } else if (n == 0) {
 381                 if (log != log_state) {
 382                         talloc_free(log);
 383                 }
 384                 return;
 385         }
 386
 387         while (log->buf_used > 0 &&
 388                (p = memchr(log->buf, '\n', log->buf_used)) != NULL) {
 389                 int n1 = (p - log->buf)+1;
 390                 int n2 = n1 - 1;
 391                 /* swallow \r from child processes */
 392                 if (n2 > 0 && log->buf[n2-1] == '\r') {
 393                         n2--;
 394                 }
 395                 write_to_log(log, log->buf, n2);
 396                 memmove(log->buf, p+1, sizeof(log->buf) - n1);
 397                 log->buf_used -= n1;
 398         }
 399
 400         /* the buffer could have completely filled - unfortunately we have
 401            no choice but to dump it out straight away */
 402         if (log->buf_used == sizeof(log->buf)) {
 403                 write_to_log(log, log->buf, log->buf_used);
 404                 log->buf_used = 0;
 405         }
 406 }
 407
 408 static int log_context_destructor(struct ctdb_log_state *log)
 409 {
 410         /* Flush buffer in case it wasn't \n-terminated. */
 411         if (log->buf_used > 0) {
 412                 write_to_log(log, log->buf, log->buf_used);
 413         }
 414         return 0;
 415 }
 416
 417 /*
 418  * vfork + exec, redirecting child output to logging and specified callback.
 419  */
 420 struct ctdb_log_state *ctdb_vfork_with_logging(TALLOC_CTX *mem_ctx,
 421                                                struct ctdb_context *ctdb,
 422                                                const char *log_prefix,
 423                                                const char *helper,
 424                                                int helper_argc,
 425                                                const char **helper_argv,
 426                                                void (*logfn)(const char *, uint16_t, void *),
 427                                                void *logfn_private, pid_t *pid)
 428 {
 429         int p[2];
 430         struct ctdb_log_state *log;
 431         struct tevent_fd *fde;
 432         char **argv;
 433         int i;
 434
 435         log = talloc_zero(mem_ctx, struct ctdb_log_state);
 436         CTDB_NO_MEMORY_NULL(ctdb, log);
 437
 438         log->prefix = log_prefix;
 439         log->logfn = logfn;
 440         log->logfn_private = logfn_private;
 441
 442         if (pipe(p) != 0) {
 443                 DEBUG(DEBUG_ERR, (__location__ " Failed to setup pipe for child logging\n"));
 444                 goto free_log;
 445         }
 446
 447         argv = talloc_array(mem_ctx, char *, helper_argc + 2);
 448         if (argv == NULL) {
 449                 DEBUG(DEBUG_ERR, (__location__ "Failed to allocate memory for helper\n"));
 450                 goto free_log;
 451         }
 452         argv[0] = discard_const(helper);
 453         argv[1] = talloc_asprintf(argv, "%d", p[1]);
 454         if (argv[1] == NULL) {
 455                 DEBUG(DEBUG_ERR, (__location__ "Failed to allocate memory for helper\n"));
 456                 talloc_free(argv);
 457                 goto free_log;
 458         }
 459
 460         for (i=0; i<helper_argc; i++) {
 461                 argv[i+2] = discard_const(helper_argv[i]);
 462         }
 463
 464         *pid = vfork();
 465         if (*pid == 0) {
 466                 execv(helper, argv);
 467                 _exit(1);
 468         }
 469         close(p[1]);
 470
 471         if (*pid < 0) {
 472                 DEBUG(DEBUG_ERR, (__location__ "vfork failed for helper process\n"));
 473                 close(p[0]);
 474                 goto free_log;
 475         }
 476
 477         ctdb_track_child(ctdb, *pid);
 478
 479         log->pfd = p[0];
 480         set_close_on_exec(log->pfd);
 481         talloc_set_destructor(log, log_context_destructor);
 482         fde = tevent_add_fd(ctdb->ev, log, log->pfd, EVENT_FD_READ,
 483                             ctdb_child_log_handler, log);
 484         tevent_fd_set_auto_close(fde);
 485
 486         return log;
 487
 488 free_log:
 489         talloc_free(log);
 490         return NULL;
 491 }
 492
 493
 494 /*
 495   setup for logging of child process stdout
 496 */
 497 int ctdb_set_child_logging(struct ctdb_context *ctdb)
 498 {
 499         int p[2];
 500         int old_stdout, old_stderr;
 501         struct tevent_fd *fde;
 502
 503         if (log_state->fd == STDOUT_FILENO) {
 504                 /* not needed for stdout logging */
 505                 return 0;
 506         }
 507
 508         /* setup a pipe to catch IO from subprocesses */
 509         if (pipe(p) != 0) {
 510                 DEBUG(DEBUG_ERR,(__location__ " Failed to setup for child logging pipe\n"));
 511                 return -1;
 512         }
 513
 514         /* We'll fail if stderr/stdout not already open; it's simpler. */
 515         old_stdout = dup(STDOUT_FILENO);
 516         old_stderr = dup(STDERR_FILENO);
 517         if (old_stdout < 0 || old_stderr < 0) {
 518                 DEBUG(DEBUG_ERR, ("Failed to dup stdout/stderr for child logging\n"));
 519                 return -1;
 520         }
 521         if (dup2(p[1], STDOUT_FILENO) < 0 || dup2(p[1], STDERR_FILENO) < 0) {
 522                 int saved_errno = errno;
 523                 dup2(old_stdout, STDOUT_FILENO);
 524                 dup2(old_stderr, STDERR_FILENO);
 525                 close(old_stdout);
 526                 close(old_stderr);
 527                 close(p[0]);
 528                 close(p[1]);
 529                 errno = saved_errno;
 530
 531                 printf(__location__ " dup2 failed: %s\n",
 532                         strerror(errno));
 533                 return -1;
 534         }
 535         close(p[1]);
 536         close(old_stdout);
 537         close(old_stderr);
 538
 539         fde = event_add_fd(ctdb->ev, log_state, p[0],
 540                            EVENT_FD_READ, ctdb_child_log_handler, log_state);
 541         tevent_fd_set_auto_close(fde);
 542
 543         log_state->pfd = p[0];
 544
 545         DEBUG(DEBUG_DEBUG, (__location__ " Created PIPE FD:%d for logging\n", p[0]));
 546
 547         return 0;
 548 }
 549
 550
 551 /*
 552  * set up a log handler to catch logging from TEVENT
 553  */
 554 static void ctdb_tevent_logging(void *private_data,
 555                                 enum tevent_debug_level level,
 556                                 const char *fmt,
 557                                 va_list ap)
 558 {
 559         enum debug_level lvl = DEBUG_CRIT;
 560
 561         switch (level) {
 562         case TEVENT_DEBUG_FATAL:
 563                 lvl = DEBUG_CRIT;
 564                 break;
 565         case TEVENT_DEBUG_ERROR:
 566                 lvl = DEBUG_ERR;
 567                 break;
 568         case TEVENT_DEBUG_WARNING:
 569                 lvl = DEBUG_WARNING;
 570                 break;
 571         case TEVENT_DEBUG_TRACE:
 572                 lvl = DEBUG_DEBUG;
 573                 break;
 574         }
 575
 576         if (lvl <= DEBUGLEVEL) {
 577                 dbgtext(fmt, ap);
 578         }
 579 }
 580
 581 int ctdb_init_tevent_logging(struct ctdb_context *ctdb)
 582 {
 583         int ret;
 584
 585         ret = tevent_set_debug(ctdb->ev,
 586                         ctdb_tevent_logging,
 587                         ctdb);
 588         return ret;
 589 }