11 #include <sys/types.h>
19 #include "appconfig.h"
21 #include "web_client.h"
22 #include "plugins_d.h"
28 #define BACKTRACE_SIZE 4096
30 void print_backtrace()
32 void *buffer[BACKTRACE_SIZE];
35 nptrs = backtrace(buffer, BACKTRACE_SIZE);
36 fprintf(stderr, "\n\nSTACK TRACE (%d addresses):\n\n", nptrs);
37 backtrace_symbols_fd(buffer, nptrs, STDERR_FILENO);
38 fprintf(stderr, "\n\n");
41 void sig_handler(int signo)
53 info("Death signaled exit (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
55 signal(signo, SIG_DFL);
65 info("Signaled exit (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
67 signal(SIGPIPE, SIG_IGN);
68 signal(SIGTERM, SIG_IGN);
69 signal(SIGQUIT, SIG_IGN);
70 signal(SIGHUP, SIG_IGN);
71 signal(SIGINT, SIG_IGN);
72 signal(SIGCHLD, SIG_IGN);
75 //unlink("/var/run/netdata.pid");
76 info("NetData exiting. Bye bye...");
81 info("Signaled PIPE (signal %d). Errno: %d (%s)", signo, errno, strerror(errno));
82 // this is received when web clients send a reset
84 // info("Ignoring signal %d. Errno: %d (%s)", signo, errno, strerror(errno));
88 info("Signal %d received. Falling back to default action for it.", signo);
89 signal(signo, SIG_DFL);
94 char rundir[FILENAME_MAX + 1] = "/var/run/netdata";
95 char pidfile[FILENAME_MAX + 1] = "";
96 void prepare_rundir() {
98 mkdir("/run/user", 0775);
99 snprintf(rundir, FILENAME_MAX, "/run/user/%d", getuid());
101 snprintf(rundir, FILENAME_MAX, "/run/user/%d/netdata", getuid());
104 snprintf(pidfile, FILENAME_MAX, "%s/netdata.pid", rundir);
106 if(mkdir(rundir, 0775) != 0) {
107 if(errno != EEXIST) fprintf(stderr, "Cannot create directory '%s' (%s).", rundir, strerror(errno));
111 int become_user(const char *username)
113 struct passwd *pw = getpwnam(username);
115 error("User %s is not present. Error: %s\n", username, strerror(errno));
119 if(chown(rundir, pw->pw_uid, pw->pw_gid) != 0) {
120 error("Cannot chown directory '%s' to user %s. Error: %s\n", rundir, username, strerror(errno));
124 if(setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
125 error("Cannot switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
129 if(setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) != 0) {
130 error("Cannot switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
134 if(setgid(pw->pw_gid) != 0) {
135 error("Cannot switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
138 if(setegid(pw->pw_gid) != 0) {
139 error("Cannot effectively switch to user's %s group (gid: %d). Error: %s\n", username, pw->pw_gid, strerror(errno));
142 if(setuid(pw->pw_uid) != 0) {
143 error("Cannot switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
146 if(seteuid(pw->pw_uid) != 0) {
147 error("Cannot effectively switch to user %s (uid: %d). Error: %s\n", username, pw->pw_uid, strerror(errno));
154 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)
158 // open the files before forking
159 int input_fd = -1, output_fd = -1, error_fd = -1, dev_null = -1;
161 if(input && *input) {
162 if((input_fd = open(input, O_RDONLY, 0666)) == -1) {
163 fprintf(stderr, "Cannot open input file '%s' (%s).\n", input, strerror(errno));
168 if(output && *output) {
169 if((output_fd = open(output, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
170 fprintf(stderr, "Cannot open output log file '%s' (%s).\n", output, strerror(errno));
171 if(input_fd != -1) close(input_fd);
176 if(error && *error) {
177 if((error_fd = open(error, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
178 fprintf(stderr, "Cannot open error log file '%s' (%s).\n", error, strerror(errno));
179 if(input_fd != -1) close(input_fd);
180 if(output_fd != -1) close(output_fd);
185 if(access && *access && access_fd) {
186 if((*access_fd = open(access, O_RDWR | O_APPEND | O_CREAT, 0666)) == -1) {
187 fprintf(stderr, "Cannot open access log file '%s' (%s).\n", access, strerror(errno));
188 if(input_fd != -1) close(input_fd);
189 if(output_fd != -1) close(output_fd);
190 if(error_fd != -1) close(error_fd);
195 *access_fp = fdopen(*access_fd, "w");
197 fprintf(stderr, "Cannot migrate file's '%s' fd %d (%s).\n", access, *access_fd, strerror(errno));
198 if(input_fd != -1) close(input_fd);
199 if(output_fd != -1) close(output_fd);
200 if(error_fd != -1) close(error_fd);
208 if((dev_null = open("/dev/null", O_RDWR, 0666)) == -1) {
209 perror("Cannot open /dev/null");
210 if(input_fd != -1) close(input_fd);
211 if(output_fd != -1) close(output_fd);
212 if(error_fd != -1) close(error_fd);
213 if(access && access_fd && *access_fd != -1) {
230 perror("cannot fork");
234 exit(0); // the parent
237 // become session leader
239 perror("Cannot become session leader.");
244 signal(SIGCHLD, SIG_IGN);
245 signal(SIGHUP, SIG_IGN);
246 signal(SIGWINCH, SIG_IGN);
252 perror("cannot fork");
256 exit(0); // the parent
260 // Set new file permissions
264 if(close_all_files) {
266 for(i = sysconf(_SC_OPEN_MAX); i > 0; i--)
268 ((access_fd && i != *access_fd) || !access_fd)
278 close(STDOUT_FILENO);
279 close(STDERR_FILENO);
282 // put the opened files
283 // to our standard file descriptors
285 if(input_fd != STDIN_FILENO) {
286 dup2(input_fd, STDIN_FILENO);
291 else dup2(dev_null, STDIN_FILENO);
293 if(output_fd != -1) {
294 if(output_fd != STDOUT_FILENO) {
295 dup2(output_fd, STDOUT_FILENO);
300 else dup2(dev_null, STDOUT_FILENO);
303 if(error_fd != STDERR_FILENO) {
304 dup2(error_fd, STDERR_FILENO);
309 else dup2(dev_null, STDERR_FILENO);
312 if(dev_null != STDIN_FILENO && dev_null != STDOUT_FILENO && dev_null != STDERR_FILENO)
315 // generate our pid file
318 int fd = open(pidfile, O_RDWR | O_CREAT, 0666);
321 sprintf(b, "%d\n", getpid());
322 int i = write(fd, b, strlen(b));
323 if(i <= 0) perror("Cannot write pid to file.");
329 if(become_user(user) != 0) {
330 error("Cannot become user '%s'. Continuing as we are.", user);
332 else info("Successfully became user '%s'.", user);