2 * collectd - src/exec.c
3 * Copyright (C) 2007-2009 Florian octo Forster
4 * Copyright (C) 2007-2009 Sebastian Harl
5 * Copyright (C) 2008 Peter Holik
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; only version 2 of the License is applicable.
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 * Florian octo Forster <octo at verplant.org>
22 * Sebastian Harl <sh at tokkee.org>
23 * Peter Holik <peter at holik.at>
26 #define _BSD_SOURCE /* For setgroups */
32 #include "utils_cmd_putval.h"
33 #include "utils_cmd_putnotif.h"
35 #include <sys/types.h>
42 #define PL_NORMAL 0x01
43 #define PL_NOTIF_ACTION 0x02
45 #define PL_RUNNING 0x10
51 * Access to this structure is serialized using the `pl_lock' lock and the
52 * `PL_RUNNING' flag. The execution of notifications is *not* serialized, so
53 * all functions used to handle notifications MUST NOT write to this structure.
54 * The `pid' and `status' fields are thus unused if the `PL_NOTIF_ACTION' flag
56 * The `PL_RUNNING' flag is set in `exec_read' and unset in `exec_read_one'.
58 struct program_list_s;
59 typedef struct program_list_s program_list_t;
72 typedef struct program_list_and_notification_s
76 } program_list_and_notification_t;
81 static program_list_t *pl_head = NULL;
82 static pthread_mutex_t pl_lock = PTHREAD_MUTEX_INITIALIZER;
87 static void sigchld_handler (int __attribute__((unused)) signal) /* {{{ */
91 while ((pid = waitpid (-1, &status, WNOHANG)) > 0)
94 for (pl = pl_head; pl != NULL; pl = pl->next)
99 } /* while (waitpid) */
100 } /* void sigchld_handler }}} */
102 static int exec_config_exec (oconfig_item_t *ci) /* {{{ */
108 if (ci->children_num != 0)
110 WARNING ("exec plugin: The config option `%s' may not be a block.",
114 if (ci->values_num < 2)
116 WARNING ("exec plugin: The config option `%s' needs at least two "
117 "arguments.", ci->key);
120 if ((ci->values[0].type != OCONFIG_TYPE_STRING)
121 || (ci->values[1].type != OCONFIG_TYPE_STRING))
123 WARNING ("exec plugin: The first two arguments to the `%s' option must "
124 "be string arguments.", ci->key);
128 pl = (program_list_t *) malloc (sizeof (program_list_t));
131 ERROR ("exec plugin: malloc failed.");
134 memset (pl, '\0', sizeof (program_list_t));
136 if (strcasecmp ("NotificationExec", ci->key) == 0)
137 pl->flags |= PL_NOTIF_ACTION;
139 pl->flags |= PL_NORMAL;
141 pl->user = strdup (ci->values[0].value.string);
142 if (pl->user == NULL)
144 ERROR ("exec plugin: strdup failed.");
149 pl->group = strchr (pl->user, ':');
150 if (pl->group != NULL)
156 pl->exec = strdup (ci->values[1].value.string);
157 if (pl->exec == NULL)
159 ERROR ("exec plugin: strdup failed.");
165 pl->argv = (char **) malloc (ci->values_num * sizeof (char *));
166 if (pl->argv == NULL)
168 ERROR ("exec plugin: malloc failed.");
174 memset (pl->argv, '\0', ci->values_num * sizeof (char *));
177 char *tmp = strrchr (ci->values[1].value.string, '/');
179 sstrncpy (buffer, ci->values[1].value.string, sizeof (buffer));
181 sstrncpy (buffer, tmp + 1, sizeof (buffer));
183 pl->argv[0] = strdup (buffer);
184 if (pl->argv[0] == NULL)
186 ERROR ("exec plugin: malloc failed.");
194 for (i = 1; i < (ci->values_num - 1); i++)
196 if (ci->values[i + 1].type == OCONFIG_TYPE_STRING)
198 pl->argv[i] = strdup (ci->values[i + 1].value.string);
202 if (ci->values[i + 1].type == OCONFIG_TYPE_NUMBER)
204 ssnprintf (buffer, sizeof (buffer), "%lf",
205 ci->values[i + 1].value.number);
209 if (ci->values[i + 1].value.boolean)
210 sstrncpy (buffer, "true", sizeof (buffer));
212 sstrncpy (buffer, "false", sizeof (buffer));
215 pl->argv[i] = strdup (buffer);
218 if (pl->argv[i] == NULL)
220 ERROR ("exec plugin: strdup failed.");
225 if (i < (ci->values_num - 1))
238 for (i = 0; pl->argv[i] != NULL; i++)
240 DEBUG ("exec plugin: argv[%i] = %s", i, pl->argv[i]);
247 } /* int exec_config_exec }}} */
249 static int exec_config (oconfig_item_t *ci) /* {{{ */
253 for (i = 0; i < ci->children_num; i++)
255 oconfig_item_t *child = ci->children + i;
256 if ((strcasecmp ("Exec", child->key) == 0)
257 || (strcasecmp ("NotificationExec", child->key) == 0))
258 exec_config_exec (child);
261 WARNING ("exec plugin: Unknown config option `%s'.", child->key);
266 } /* int exec_config }}} */
268 static void set_environment (void) /* {{{ */
272 ssnprintf (buffer, sizeof (buffer), "%i", interval_g);
273 setenv ("COLLECTD_INTERVAL", buffer, /* overwrite = */ 1);
275 ssnprintf (buffer, sizeof (buffer), "%s", hostname_g);
276 setenv ("COLLECTD_HOSTNAME", buffer, /* overwrite = */ 1);
277 } /* }}} void set_environment */
279 static void exec_child (program_list_t *pl) /* {{{ */
286 struct passwd *sp_ptr;
292 status = getpwnam_r (pl->user, &sp, nambuf, sizeof (nambuf), &sp_ptr);
295 ERROR ("exec plugin: getpwnam_r failed: %s",
296 sstrerror (errno, errbuf, sizeof (errbuf)));
301 ERROR ("exec plugin: No such user: `%s'", pl->user);
309 ERROR ("exec plugin: Cowardly refusing to exec program as root.");
313 /* The group configured in the configfile is set as effective group, because
314 * this way the forked process can (re-)gain the user's primary group. */
316 if (NULL != pl->group)
318 if ('\0' != *pl->group) {
319 struct group *gr_ptr = NULL;
322 status = getgrnam_r (pl->group, &gr, nambuf, sizeof (nambuf), &gr_ptr);
325 ERROR ("exec plugin: getgrnam_r failed: %s",
326 sstrerror (errno, errbuf, sizeof (errbuf)));
331 ERROR ("exec plugin: No such group: `%s'", pl->group);
341 } /* if (pl->group == NULL) */
352 if ((gid != egid) && (egid != -1))
358 setgroups (glist_len, glist);
360 #endif /* HAVE_SETGROUPS */
362 status = setgid (gid);
365 ERROR ("exec plugin: setgid (%i) failed: %s",
366 gid, sstrerror (errno, errbuf, sizeof (errbuf)));
372 status = setegid (egid);
375 ERROR ("exec plugin: setegid (%i) failed: %s",
376 egid, sstrerror (errno, errbuf, sizeof (errbuf)));
381 status = setuid (uid);
384 ERROR ("exec plugin: setuid (%i) failed: %s",
385 uid, sstrerror (errno, errbuf, sizeof (errbuf)));
389 status = execvp (pl->exec, pl->argv);
391 ERROR ("exec plugin: exec failed: %s",
392 sstrerror (errno, errbuf, sizeof (errbuf)));
394 } /* void exec_child }}} */
396 static void reset_signal_mask (void) /* {{{ */
400 memset (&ss, 0, sizeof (ss));
402 sigprocmask (SIG_SETMASK, &ss, /* old mask = */ NULL);
403 } /* }}} void reset_signal_mask */
406 * Creates three pipes (one for reading, one for writing and one for errors),
407 * forks a child, sets up the pipes so that fd_in is connected to STDIN of
408 * the child and fd_out is connected to STDOUT and fd_err is connected to STDERR
409 * of the child. Then is calls `exec_child'.
411 static int fork_child (program_list_t *pl, int *fd_in, int *fd_out, int *fd_err) /* {{{ */
423 status = pipe (fd_pipe_in);
426 ERROR ("exec plugin: pipe failed: %s",
427 sstrerror (errno, errbuf, sizeof (errbuf)));
431 status = pipe (fd_pipe_out);
434 ERROR ("exec plugin: pipe failed: %s",
435 sstrerror (errno, errbuf, sizeof (errbuf)));
439 status = pipe (fd_pipe_err);
442 ERROR ("exec plugin: pipe failed: %s",
443 sstrerror (errno, errbuf, sizeof (errbuf)));
450 ERROR ("exec plugin: fork failed: %s",
451 sstrerror (errno, errbuf, sizeof (errbuf)));
459 /* Close all file descriptors but the pipe end we need. */
460 fd_num = getdtablesize ();
461 for (fd = 0; fd < fd_num; fd++)
463 if ((fd == fd_pipe_in[0])
464 || (fd == fd_pipe_out[1])
465 || (fd == fd_pipe_err[1]))
470 /* Connect the `in' pipe to STDIN */
471 if (fd_pipe_in[0] != STDIN_FILENO)
473 dup2 (fd_pipe_in[0], STDIN_FILENO);
474 close (fd_pipe_in[0]);
477 /* Now connect the `out' pipe to STDOUT */
478 if (fd_pipe_out[1] != STDOUT_FILENO)
480 dup2 (fd_pipe_out[1], STDOUT_FILENO);
481 close (fd_pipe_out[1]);
484 /* Now connect the `out' pipe to STDOUT */
485 if (fd_pipe_err[1] != STDERR_FILENO)
487 dup2 (fd_pipe_err[1], STDERR_FILENO);
488 close (fd_pipe_err[1]);
493 /* Unblock all signals */
494 reset_signal_mask ();
497 /* does not return */
500 close (fd_pipe_in[0]);
501 close (fd_pipe_out[1]);
502 close (fd_pipe_err[1]);
505 *fd_in = fd_pipe_in[1];
507 close (fd_pipe_in[1]);
510 *fd_out = fd_pipe_out[0];
512 close (fd_pipe_out[0]);
515 *fd_err = fd_pipe_err[0];
517 close (fd_pipe_err[0]);
520 } /* int fork_child }}} */
522 static int parse_line (char *buffer) /* {{{ */
524 if (strncasecmp ("PUTVAL", buffer, strlen ("PUTVAL")) == 0)
525 return (handle_putval (stdout, buffer));
526 else if (strncasecmp ("PUTNOTIF", buffer, strlen ("PUTNOTIF")) == 0)
527 return (handle_putnotif (stdout, buffer));
530 /* For backwards compatibility */
532 /* Let's annoy the user a bit.. */
533 INFO ("exec plugin: Prepending `PUTVAL' to this line: %s", buffer);
534 ssnprintf (tmp, sizeof (tmp), "PUTVAL %s", buffer);
535 return (handle_putval (stdout, tmp));
537 } /* int parse_line }}} */
539 static void *exec_read_one (void *arg) /* {{{ */
541 program_list_t *pl = (program_list_t *) arg;
542 int fd, fd_err, highest_fd;
545 char buffer[1200]; /* if not completely read */
546 char buffer_err[1024];
547 char *pbuffer = buffer;
548 char *pbuffer_err = buffer_err;
550 status = fork_child (pl, NULL, &fd, &fd_err);
552 pthread_exit ((void *) 1);
555 assert (pl->pid != 0);
559 FD_SET(fd_err, &fdset);
561 /* Determine the highest file descriptor */
562 highest_fd = (fd > fd_err) ? fd : fd_err;
564 /* We use a copy of fdset, as select modifies it */
567 while (select(highest_fd + 1, ©, NULL, NULL, NULL ) > 0)
571 if (FD_ISSET(fd, ©))
575 len = read(fd, pbuffer, sizeof(buffer) - 1 - (pbuffer - buffer));
579 if (errno == EAGAIN || errno == EINTR) continue;
582 else if (len == 0) break; /* We've reached EOF */
586 len += pbuffer - buffer;
589 while ((pnl = strchr(pbuffer, '\n')))
592 if (*(pnl-1) == '\r' ) *(pnl-1) = '\0';
594 parse_line (pbuffer);
598 /* not completely read ? */
599 if (pbuffer - buffer < len)
601 len -= pbuffer - buffer;
602 memmove(buffer, pbuffer, len);
603 pbuffer = buffer + len;
608 else if (FD_ISSET(fd_err, ©))
612 len = read(fd_err, pbuffer_err, sizeof(buffer_err) - 1 - (pbuffer_err - buffer_err));
616 if (errno == EAGAIN || errno == EINTR) continue;
621 /* We've reached EOF */
622 NOTICE ("exec plugin: Program `%s' has closed STDERR.",
625 FD_CLR (fd_err, &fdset);
631 pbuffer_err[len] = '\0';
633 len += pbuffer_err - buffer_err;
634 pbuffer_err = buffer_err;
636 while ((pnl = strchr(pbuffer_err, '\n')))
639 if (*(pnl-1) == '\r' ) *(pnl-1) = '\0';
641 ERROR ("exec plugin: exec_read_one: error = %s", pbuffer_err);
645 /* not completely read ? */
646 if (pbuffer_err - buffer_err < len)
648 len -= pbuffer_err - buffer_err;
649 memmove(buffer_err, pbuffer_err, len);
650 pbuffer_err = buffer_err + len;
653 pbuffer_err = buffer_err;
659 DEBUG ("exec plugin: exec_read_one: Waiting for `%s' to exit.", pl->exec);
660 if (waitpid (pl->pid, &status, 0) > 0)
663 DEBUG ("exec plugin: Child %i exited with status %i.",
664 (int) pl->pid, pl->status);
668 pthread_mutex_lock (&pl_lock);
669 pl->flags &= ~PL_RUNNING;
670 pthread_mutex_unlock (&pl_lock);
676 pthread_exit ((void *) 0);
678 } /* void *exec_read_one }}} */
680 static void *exec_notification_one (void *arg) /* {{{ */
682 program_list_t *pl = ((program_list_and_notification_t *) arg)->pl;
683 notification_t *n = &((program_list_and_notification_t *) arg)->n;
684 notification_meta_t *meta;
689 const char *severity;
691 pid = fork_child (pl, &fd, NULL, NULL);
694 pthread_exit ((void *) 1);
697 fh = fdopen (fd, "w");
701 ERROR ("exec plugin: fdopen (%i) failed: %s", fd,
702 sstrerror (errno, errbuf, sizeof (errbuf)));
703 kill (pl->pid, SIGTERM);
707 pthread_exit ((void *) 1);
710 severity = "FAILURE";
711 if (n->severity == NOTIF_WARNING)
712 severity = "WARNING";
713 else if (n->severity == NOTIF_OKAY)
719 severity, (unsigned int) n->time);
721 /* Print the optional fields */
722 if (strlen (n->host) > 0)
723 fprintf (fh, "Host: %s\n", n->host);
724 if (strlen (n->plugin) > 0)
725 fprintf (fh, "Plugin: %s\n", n->plugin);
726 if (strlen (n->plugin_instance) > 0)
727 fprintf (fh, "PluginInstance: %s\n", n->plugin_instance);
728 if (strlen (n->type) > 0)
729 fprintf (fh, "Type: %s\n", n->type);
730 if (strlen (n->type_instance) > 0)
731 fprintf (fh, "TypeInstance: %s\n", n->type_instance);
733 for (meta = n->meta; meta != NULL; meta = meta->next)
735 if (meta->type == NM_TYPE_STRING)
736 fprintf (fh, "%s: %s\n", meta->name, meta->nm_value.nm_string);
737 else if (meta->type == NM_TYPE_SIGNED_INT)
738 fprintf (fh, "%s: %"PRIi64"\n", meta->name, meta->nm_value.nm_signed_int);
739 else if (meta->type == NM_TYPE_UNSIGNED_INT)
740 fprintf (fh, "%s: %"PRIu64"\n", meta->name, meta->nm_value.nm_unsigned_int);
741 else if (meta->type == NM_TYPE_DOUBLE)
742 fprintf (fh, "%s: %e\n", meta->name, meta->nm_value.nm_double);
743 else if (meta->type == NM_TYPE_BOOLEAN)
744 fprintf (fh, "%s: %s\n", meta->name,
745 meta->nm_value.nm_boolean ? "true" : "false");
748 fprintf (fh, "\n%s\n", n->message);
753 waitpid (pid, &status, 0);
755 DEBUG ("exec plugin: Child %i exited with status %i.",
759 plugin_notification_meta_free (n->meta);
762 pthread_exit ((void *) 0);
764 } /* void *exec_notification_one }}} */
766 static int exec_init (void) /* {{{ */
770 memset (&sa, '\0', sizeof (sa));
771 sa.sa_handler = sigchld_handler;
772 sigaction (SIGCHLD, &sa, NULL);
775 } /* int exec_init }}} */
777 static int exec_read (void) /* {{{ */
781 for (pl = pl_head; pl != NULL; pl = pl->next)
786 /* Only execute `normal' style executables here. */
787 if ((pl->flags & PL_NORMAL) == 0)
790 pthread_mutex_lock (&pl_lock);
791 /* Skip if a child is already running. */
792 if ((pl->flags & PL_RUNNING) != 0)
794 pthread_mutex_unlock (&pl_lock);
797 pl->flags |= PL_RUNNING;
798 pthread_mutex_unlock (&pl_lock);
800 pthread_attr_init (&attr);
801 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
802 pthread_create (&t, &attr, exec_read_one, (void *) pl);
806 } /* int exec_read }}} */
808 static int exec_notification (const notification_t *n,
809 user_data_t __attribute__((unused)) *user_data)
812 program_list_and_notification_t *pln;
814 for (pl = pl_head; pl != NULL; pl = pl->next)
819 /* Only execute `notification' style executables here. */
820 if ((pl->flags & PL_NOTIF_ACTION) == 0)
823 /* Skip if a child is already running. */
827 pln = (program_list_and_notification_t *) malloc (sizeof
828 (program_list_and_notification_t));
831 ERROR ("exec plugin: malloc failed.");
836 memcpy (&pln->n, n, sizeof (notification_t));
838 /* Set the `meta' member to NULL, otherwise `plugin_notification_meta_copy'
839 * will run into an endless loop. */
841 plugin_notification_meta_copy (&pln->n, n);
843 pthread_attr_init (&attr);
844 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
845 pthread_create (&t, &attr, exec_notification_one, (void *) pln);
849 } /* }}} int exec_notification */
851 static int exec_shutdown (void) /* {{{ */
854 program_list_t *next;
863 kill (pl->pid, SIGTERM);
864 INFO ("exec plugin: Sent SIGTERM to %hu", (unsigned short int) pl->pid);
875 } /* int exec_shutdown }}} */
877 void module_register (void)
879 plugin_register_complex_config ("exec", exec_config);
880 plugin_register_init ("exec", exec_init);
881 plugin_register_read ("exec", exec_read);
882 plugin_register_notification ("exec", exec_notification,
883 /* user_data = */ NULL);
884 plugin_register_shutdown ("exec", exec_shutdown);
885 } /* void module_register */
888 * vim:shiftwidth=2:softtabstop=2:tabstop=8:fdm=marker