/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2010 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include <unistd.h> #include <stdio.h> #include <errno.h> #include <string.h> #include <stdlib.h> #include "hostname-setup.h" #include "macro.h" #include "util.h" #include "log.h" #include "fileio.h" static int read_and_strip_hostname(const char *path, char **hn) { char *s; int r; assert(path); assert(hn); r = read_one_line_file(path, &s); if (r < 0) return r; hostname_cleanup(s); if (isempty(s)) { free(s); return -ENOENT; } *hn = s; return 0; } int hostname_setup(void) { int r; _cleanup_free_ char *b = NULL; const char *hn; bool enoent = false; r = read_and_strip_hostname("/etc/hostname", &b); if (r < 0) { if (r == -ENOENT) enoent = true; else log_warning("Failed to read configured hostname: %s", strerror(-r)); hn = NULL; } else hn = b; if (isempty(hn)) { /* Don't override the hostname if it is already set * and not explicitly configured */ if (hostname_is_set()) return 0; if (enoent) log_info("No hostname configured."); hn = "localhost"; } if (sethostname(hn, strlen(hn)) < 0) { log_warning("Failed to set hostname to <%s>: %m", hn); return -errno; } log_info("Set hostname to <%s>.", hn); return 0; }