11 #include <sys/types.h>
19 #include "appconfig.h"
21 #include "web_client.h"
22 #include "plugins_d.h"
28 void sig_handler(int signo)
40 info("Death signaled exit (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
41 signal(signo, SIG_DFL);
51 info("Signaled exit (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
52 signal(SIGPIPE, SIG_IGN);
53 signal(SIGTERM, SIG_IGN);
54 signal(SIGQUIT, SIG_IGN);
55 signal(SIGHUP, SIG_IGN);
56 signal(SIGINT, SIG_IGN);
57 signal(SIGCHLD, SIG_IGN);
58 netdata_cleanup_and_exit(1);
62 info("Signaled PIPE (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
63 // this is received when web clients send a reset
65 // info("Ignoring signal %d. Errno: %d (%s)", signo, errno, strerror(errno));
69 info("Signal %d received. Falling back to default action for it.", signo);
70 signal(signo, SIG_DFL);
75 char rundir[FILENAME_MAX + 1] = "/var/run/netdata";
76 char pidfile[FILENAME_MAX + 1] = "";
77 void prepare_rundir() {
79 mkdir("/run/user", 0775);
80 snprintf(rundir, FILENAME_MAX, "/run/user/%d", getuid());
82 snprintf(rundir, FILENAME_MAX, "/run/user/%d/netdata", getuid());
85 snprintf(pidfile, FILENAME_MAX, "%s/netdata.pid", rundir);
87 if(mkdir(rundir, 0775) != 0) {
88 if(errno != EEXIST) fprintf(stderr, "Cannot create directory '%s' (%s).", rundir, strerror(errno));
92 int become_user(const char *username)
94 struct passwd *pw = getpwnam(username);
96 error("User %s is not present. Error: %s\n", username, strerror(errno));
100 if(chown(rundir, pw->pw_uid, pw->pw_gid) != 0) {
101 error("Cannot chown directory '%s' to user %s. Error: %s\n", rundir, username, strerror(errno));
105 if(setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
106 error("Cannot switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
110 if(setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) != 0) {
111 error("Cannot switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
115 if(setgid(pw->pw_gid) != 0) {
116 error("Cannot switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
119 if(setegid(pw->pw_gid) != 0) {
120 error("Cannot effectively switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
123 if(setuid(pw->pw_uid) != 0) {
124 error("Cannot switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
127 if(seteuid(pw->pw_uid) != 0) {
128 error("Cannot effectively switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
135 int become_daemon(int dont_fork, int close_all_files, const char *user, const char *input, const char *output, const char *error, const char *access, int *access_fd, FILE **access_fp)
139 // open the files before forking
140 int input_fd = -1, output_fd = -1, error_fd = -1, dev_null = -1;
142 if(input && *input) {
143 if((input_fd = open(input, O_RDONLY, 0666)) == -1) {
144 fprintf(stderr, "Cannot open input file '%s' (%s).\n", input, strerror(errno));
149 if(output && *output) {
150 if((output_fd = open(output, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
151 fprintf(stderr, "Cannot open output log file '%s' (%s).\n", output, strerror(errno));
152 if(input_fd != -1) close(input_fd);
157 if(error && *error) {
158 if((error_fd = open(error, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
159 fprintf(stderr, "Cannot open error log file '%s' (%s).\n", error, strerror(errno));
160 if(input_fd != -1) close(input_fd);
161 if(output_fd != -1) close(output_fd);
166 if(access && *access && access_fd) {
167 if((*access_fd = open(access, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
168 fprintf(stderr, "Cannot open access log file '%s' (%s).\n", access, strerror(errno));
169 if(input_fd != -1) close(input_fd);
170 if(output_fd != -1) close(output_fd);
171 if(error_fd != -1) close(error_fd);
176 *access_fp = fdopen(*access_fd, "w");
178 fprintf(stderr, "Cannot migrate file's '%s' fd %d (%s).\n", access, *access_fd, strerror(errno));
179 if(input_fd != -1) close(input_fd);
180 if(output_fd != -1) close(output_fd);
181 if(error_fd != -1) close(error_fd);
189 if((dev_null = open("/dev/null", O_RDWR, 0666)) == -1) {
190 perror("Cannot open /dev/null");
191 if(input_fd != -1) close(input_fd);
192 if(output_fd != -1) close(output_fd);
193 if(error_fd != -1) close(error_fd);
194 if(access && access_fd && *access_fd != -1) {
211 perror("cannot fork");
215 exit(0); // the parent
218 // become session leader
220 perror("Cannot become session leader.");
225 signal(SIGCHLD, SIG_IGN);
226 signal(SIGHUP, SIG_IGN);
227 signal(SIGWINCH, SIG_IGN);
233 perror("cannot fork");
237 exit(0); // the parent
241 // Set new file permissions
245 if(close_all_files) {
247 for(i = sysconf(_SC_OPEN_MAX) - 1; i > 0; i--)
249 ((access_fd && i != *access_fd) || !access_fd)
259 close(STDOUT_FILENO);
260 close(STDERR_FILENO);
263 // put the opened files
264 // to our standard file descriptors
266 if(input_fd != STDIN_FILENO) {
267 dup2(input_fd, STDIN_FILENO);
272 else dup2(dev_null, STDIN_FILENO);
274 if(output_fd != -1) {
275 if(output_fd != STDOUT_FILENO) {
276 dup2(output_fd, STDOUT_FILENO);
281 else dup2(dev_null, STDOUT_FILENO);
284 if(error_fd != STDERR_FILENO) {
285 dup2(error_fd, STDERR_FILENO);
290 else dup2(dev_null, STDERR_FILENO);
293 if(dev_null != STDIN_FILENO && dev_null != STDOUT_FILENO && dev_null != STDERR_FILENO)
296 // generate our pid file
299 int fd = open(pidfile, O_RDWR | O_CREAT, 0666);
302 sprintf(b, "%d\n", getpid());
303 int i = write(fd, b, strlen(b));
304 if(i <= 0) perror("Cannot write pid to file.");
310 if(become_user(user) != 0) {
311 error("Cannot become user '%s'. Continuing as we are.", user);
313 else info("Successfully became user '%s'.", user);