src/getty-generator.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <string.h>
  23 #include <errno.h>
  24 #include <unistd.h>
  25
  26 #include "log.h"
  27 #include "util.h"
  28 #include "unit-name.h"
  29
  30 const char *arg_dest = "/tmp";
  31
  32 static int add_symlink(const char *fservice, const char *tservice) {
  33         char *from = NULL, *to = NULL;
  34         int r;
  35
  36         asprintf(&from, SYSTEM_DATA_UNIT_PATH "/%s", fservice);
  37         asprintf(&to, "%s/getty.target.wants/%s", arg_dest, tservice);
  38
  39         if (!from || !to) {
  40                 log_error("Out of memory");
  41                 r = -ENOMEM;
  42                 goto finish;
  43         }
  44
  45         mkdir_parents(to, 0755);
  46
  47         if ((r = symlink(from, to)) < 0) {
  48                 log_error("Failed to create symlink from %s to %s: %m", from, to);
  49                 r = -errno;
  50         }
  51
  52 finish:
  53
  54         free(from);
  55         free(to);
  56
  57         return r;
  58 }
  59
  60 int main(int argc, char *argv[]) {
  61         int r = EXIT_SUCCESS;
  62         char *active;
  63
  64         if (argc > 2) {
  65                 log_error("This program takes one or no arguments.");
  66                 return EXIT_FAILURE;
  67         }
  68
  69         if (argc > 1)
  70             arg_dest = argv[1];
  71
  72         log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
  73         log_parse_environment();
  74         log_open();
  75
  76         if (detect_container(NULL) > 0) {
  77                 log_debug("Automatic adding console shell.");
  78
  79                 if (add_symlink("console-shell.service", "console-shell.service") < 0)
  80                         r = EXIT_FAILURE;
  81
  82                 /* Don't add any further magic if we are in a container */
  83                 goto finish;
  84         }
  85
  86         if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
  87                 const char *tty;
  88
  89                 if ((tty = strrchr(active, ' ')))
  90                         tty ++;
  91                 else
  92                         tty = active;
  93
  94                 /* Automatically add in a serial getty on the kernel
  95                  * console */
  96                 if (!tty_is_vc(tty)) {
  97                         char *n;
  98
  99                         /* We assume that gettys on virtual terminals are
 100                          * started via manual configuration and do this magic
 101                          * only for non-VC terminals. */
 102
 103                         log_debug("Automatically adding serial getty for /dev/%s.", tty);
 104
 105                         if (!(n = unit_name_replace_instance("serial-getty@.service", tty)) ||
 106                             add_symlink("serial-getty@.service", n) < 0)
 107                                 r = EXIT_FAILURE;
 108
 109                         free(n);
 110                 }
 111
 112                 free(active);
 113         }
 114
 115         /* Automatically add in a serial getty on the first
 116          * virtualizer console */
 117         if (access("/sys/class/tty/hvc0", F_OK) == 0) {
 118                 log_debug("Automatic adding serial getty for hvc0.");
 119
 120                 if (add_symlink("serial-getty@.service", "serial-getty@hvc0.service") < 0)
 121                         r = EXIT_FAILURE;
 122         }
 123
 124 finish:
 125         return r;
 126 }