} /* }}} void install_signal_handlers */
-static int open_pidfile(void) /* {{{ */
+static int open_pidfile(char *action, int oflag) /* {{{ */
{
int fd;
char *file;
? config_pid_file
: LOCALSTATEDIR "/run/rrdcached.pid";
- fd = open(file, O_CREAT|O_EXCL|O_WRONLY, S_IRUSR|S_IRGRP|S_IROTH);
+ fd = open(file, oflag, S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH);
if (fd < 0)
- fprintf(stderr, "FATAL: cannot create '%s' (%s)\n",
- file, rrd_strerror(errno));
+ fprintf(stderr, "rrdcached: can't %s pid file '%s' (%s)\n",
+ action, file, rrd_strerror(errno));
return(fd);
} /* }}} static int open_pidfile */
+/* check existing pid file to see whether a daemon is running */
+static int check_pidfile(void)
+{
+ int pid_fd;
+ pid_t pid;
+ char pid_str[16];
+
+ pid_fd = open_pidfile("open", O_RDWR);
+ if (pid_fd < 0)
+ return pid_fd;
+
+ if (read(pid_fd, pid_str, sizeof(pid_str)) <= 0)
+ return -1;
+
+ pid = atoi(pid_str);
+ if (pid <= 0)
+ return -1;
+
+ /* another running process that we can signal COULD be
+ * a competing rrdcached */
+ if (pid != getpid() && kill(pid, 0) == 0)
+ {
+ fprintf(stderr,
+ "FATAL: Another rrdcached daemon is running?? (pid %d)\n", pid);
+ close(pid_fd);
+ return -1;
+ }
+
+ lseek(pid_fd, 0, SEEK_SET);
+ ftruncate(pid_fd, 0);
+
+ fprintf(stderr,
+ "rrdcached: removed stale PID file (no rrdcached on pid %d)\n"
+ "rrdcached: starting normally.\n", pid);
+
+ return pid_fd;
+} /* }}} static int check_pidfile */
+
static int write_pidfile (int fd) /* {{{ */
{
pid_t pid;
flush_old_values (config_write_interval);
/* Determine the time of the next cache flush. */
- while (next_flush.tv_sec <= now.tv_sec)
- next_flush.tv_sec += config_flush_interval;
+ next_flush.tv_sec =
+ now.tv_sec + next_flush.tv_sec % config_flush_interval;
/* unlock the cache while we rotate so we don't block incoming
* updates if the fsync() blocks on disk I/O */
return 0;
} /* }}} static int check_file_access */
+/* when using a base dir, convert relative paths to absolute paths.
+ * if necessary, modifies the "filename" pointer to point
+ * to the new path created in "tmp". "tmp" is provided
+ * by the caller and sizeof(tmp) must be >= PATH_MAX.
+ *
+ * this allows us to optimize for the expected case (absolute path)
+ * with a no-op.
+ */
+static void get_abs_path(char **filename, char *tmp)
+{
+ assert(tmp != NULL);
+ assert(filename != NULL && *filename != NULL);
+
+ if (config_base_dir == NULL || **filename == '/')
+ return;
+
+ snprintf(tmp, PATH_MAX, "%s/%s", config_base_dir, *filename);
+ *filename = tmp;
+} /* }}} static int get_abs_path */
+
/* returns 1 if we have the required privilege level,
* otherwise issue an error to the user on sock */
static int has_privilege (listen_socket_t *sock, /* {{{ */
static int handle_request_flush (listen_socket_t *sock, /* {{{ */
char *buffer, size_t buffer_size)
{
- char *file;
+ char *file, file_tmp[PATH_MAX];
int status;
status = buffer_get_field (&buffer, &buffer_size, &file);
stats_flush_received++;
pthread_mutex_unlock(&stats_lock);
+ get_abs_path(&file, file_tmp);
if (!check_file_access(file, sock)) return 0;
status = flush_file (file);
char *buffer, size_t buffer_size)
{
int status;
- char *file;
+ char *file, file_tmp[PATH_MAX];
cache_item_t *ci;
status = buffer_get_field(&buffer, &buffer_size, &file);
if (status <= 0)
return status;
+ get_abs_path(&file, file_tmp);
+
pthread_mutex_lock(&cache_lock);
ci = g_tree_lookup(cache_tree, file);
if (ci == NULL)
char *buffer, size_t buffer_size)
{
int status;
- char *file;
+ char *file, file_tmp[PATH_MAX];
status = buffer_get_field(&buffer, &buffer_size, &file);
if (status != 0)
if (status <= 0)
return status;
+ get_abs_path(&file, file_tmp);
if (!check_file_access(file, sock)) return 0;
pthread_mutex_lock(&cache_lock);
time_t now,
char *buffer, size_t buffer_size)
{
- char *file;
+ char *file, file_tmp[PATH_MAX];
int values_num = 0;
int bad_timestamps = 0;
int status;
stats_updates_received++;
pthread_mutex_unlock(&stats_lock);
+ get_abs_path(&file, file_tmp);
if (!check_file_access(file, sock)) return 0;
pthread_mutex_lock (&cache_lock);
static int daemonize (void) /* {{{ */
{
int status;
- int fd;
+ int pid_fd;
char *base_dir;
daemon_uid = geteuid();
- fd = open_pidfile();
- if (fd < 0) return fd;
+ pid_fd = open_pidfile("create", O_CREAT|O_EXCL|O_WRONLY);
+ if (pid_fd < 0)
+ pid_fd = check_pidfile();
+ if (pid_fd < 0)
+ return pid_fd;
if (!stay_foreground)
{
return (-1);
}
- status = write_pidfile (fd);
+ status = write_pidfile (pid_fd);
return status;
} /* }}} int daemonize */
case 'b':
{
size_t len;
+ char base_realpath[PATH_MAX];
if (config_base_dir != NULL)
free (config_base_dir);
return (3);
}
+ /* make sure that the base directory is not resolved via
+ * symbolic links. this makes some performance-enhancing
+ * assumptions possible (we don't have to resolve paths
+ * that start with a "/")
+ */
+ if (realpath(config_base_dir, base_realpath) == NULL)
+ {
+ fprintf (stderr, "Invalid base directory '%s'.\n", config_base_dir);
+ return 5;
+ }
+ else if (strncmp(config_base_dir,
+ base_realpath, sizeof(base_realpath)) != 0)
+ {
+ fprintf(stderr,
+ "Base directory (-b) resolved via file system links!\n"
+ "Please consult rrdcached '-b' documentation!\n"
+ "Consider specifying the real directory (%s)\n",
+ base_realpath);
+ return 5;
+ }
+
len = strlen (config_base_dir);
while ((len > 0) && (config_base_dir[len - 1] == '/'))
{
projects / rrdtool.git / blobdiff