2 * collectd - src/exec.c
3 * Copyright (C) 2007 Florian octo Forster
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; only version 2 of the License is applicable.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Florian octo Forster <octo at verplant.org>
25 #include "utils_cmd_putval.h"
27 #include <sys/types.h>
37 struct program_list_s;
38 typedef struct program_list_s program_list_t;
51 static const char *config_keys[] =
55 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
57 static program_list_t *pl_head = NULL;
62 static int exec_config (const char *key, const char *value)
64 if (strcasecmp ("Exec", key) == 0)
67 pl = (program_list_t *) malloc (sizeof (program_list_t));
70 memset (pl, '\0', sizeof (program_list_t));
72 pl->user = strdup (value);
79 pl->exec = strchr (pl->user, ' ');
86 while (*pl->exec == ' ')
92 if (*pl->exec == '\0')
102 pl->group = strchr (pl->user, ':');
103 if (NULL != pl->group) {
114 } /* int exec_config */
116 static void exec_child (program_list_t *pl)
124 struct passwd *sp_ptr;
130 status = getpwnam_r (pl->user, &sp, nambuf, sizeof (nambuf), &sp_ptr);
133 ERROR ("exec plugin: getpwnam_r failed: %s",
134 sstrerror (errno, errbuf, sizeof (errbuf)));
139 ERROR ("exec plugin: No such user: `%s'", pl->user);
147 ERROR ("exec plugin: Cowardly refusing to exec program as root.");
151 /* The group configured in the configfile is set as effective group, because
152 * this way the forked process can (re-)gain the user's primary group. */
154 if (NULL != pl->group)
156 if ('\0' != *pl->group) {
157 struct group *gr_ptr = NULL;
160 status = getgrnam_r (pl->group, &gr, nambuf, sizeof (nambuf), &gr_ptr);
163 ERROR ("exec plugin: getgrnam_r failed: %s",
164 sstrerror (errno, errbuf, sizeof (errbuf)));
169 ERROR ("exec plugin: No such group: `%s'", pl->group);
179 } /* if (pl->group == NULL) */
181 status = setgid (gid);
184 ERROR ("exec plugin: setgid (%i) failed: %s",
185 gid, sstrerror (errno, errbuf, sizeof (errbuf)));
191 status = setegid (egid);
194 ERROR ("exec plugin: setegid (%i) failed: %s",
195 egid, sstrerror (errno, errbuf, sizeof (errbuf)));
200 status = setuid (uid);
203 ERROR ("exec plugin: setuid (%i) failed: %s",
204 uid, sstrerror (errno, errbuf, sizeof (errbuf)));
208 arg0 = strrchr (pl->exec, '/');
211 if ((arg0 == NULL) || (*arg0 == '\0'))
214 status = execlp (pl->exec, arg0, (char *) 0);
216 ERROR ("exec plugin: exec failed: %s",
217 sstrerror (errno, errbuf, sizeof (errbuf)));
219 } /* void exec_child */
221 static int fork_child (program_list_t *pl)
229 status = pipe (fd_pipe);
233 ERROR ("exec plugin: pipe failed: %s",
234 sstrerror (errno, errbuf, sizeof (errbuf)));
242 ERROR ("exec plugin: fork failed: %s",
243 sstrerror (errno, errbuf, sizeof (errbuf)));
246 else if (pl->pid == 0)
250 /* Connect the pipe to STDOUT and STDERR */
251 if (fd_pipe[1] != STDOUT_FILENO)
252 dup2 (fd_pipe[1], STDOUT_FILENO);
253 if (fd_pipe[1] != STDERR_FILENO)
254 dup2 (fd_pipe[1], STDERR_FILENO);
255 if ((fd_pipe[1] != STDOUT_FILENO) && (fd_pipe[1] != STDERR_FILENO))
259 /* does not return */
264 } /* int fork_child */
266 static int parse_line (char *buffer)
271 fields[0] = "PUTVAL";
272 fields_num = strsplit (buffer, &fields[1], STATIC_ARRAY_SIZE(fields) - 1);
274 handle_putval (stdout, fields, fields_num + 1);
276 } /* int parse_line */
278 static void *exec_read_one (void *arg)
280 program_list_t *pl = (program_list_t *) arg;
285 fd = fork_child (pl);
287 pthread_exit ((void *) 1);
289 assert (pl->pid != 0);
291 fh = fdopen (fd, "r");
295 ERROR ("exec plugin: fdopen (%i) failed: %s", fd,
296 sstrerror (errno, errbuf, sizeof (errbuf)));
297 kill (pl->pid, SIGTERM);
299 pthread_exit ((void *) 1);
302 while (fgets (buffer, sizeof (buffer), fh) != NULL)
306 len = strlen (buffer);
308 /* Remove newline from end. */
309 while ((len > 0) && ((buffer[len - 1] == '\n')
310 || (buffer[len - 1] == '\r')))
311 buffer[--len] = '\0';
313 DEBUG ("exec plugin: exec_read_one: buffer = %s", buffer);
316 } /* while (fgets) */
321 pthread_exit ((void *) 0);
323 } /* void *exec_read_one */
325 static int exec_read (void)
329 for (pl = pl_head; pl != NULL; pl = pl->next)
337 pthread_attr_init (&attr);
338 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
339 pthread_create (&t, &attr, exec_read_one, (void *) pl);
343 } /* int exec_read */
345 static int exec_shutdown (void)
348 program_list_t *next;
357 kill (pl->pid, SIGTERM);
358 INFO ("exec plugin: Sent SIGTERM to %hu", (unsigned short int) pl->pid);
369 } /* int exec_shutdown */
371 void module_register (void)
373 plugin_register_config ("exec", exec_config, config_keys, config_keys_num);
374 plugin_register_read ("exec", exec_read);
375 plugin_register_shutdown ("exec", exec_shutdown);
376 } /* void module_register */
379 * vim:shiftwidth=2:softtabstop=2:tabstop=8