getty: move automatic serial getty logic into generator

1 files changed, 127 insertions, 0 deletions

diff --git a/src/getty-generator.c b/src/getty-generator.c
new file mode 100644
index 0000000000..f49f9eae99
--- /dev/null
+++ b/src/getty-generator.c
@@ -0,0 +1,127 @@
+/*-*- 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 General Public License as published by
+  the Free Software Foundation; either version 2 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
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include "log.h"
+#include "util.h"
+#include "unit-name.h"
+
+const char *arg_dest = "/tmp";
+
+static int add_symlink(const char *fservice, const char *tservice) {
+        char *from = NULL, *to = NULL;
+        int r;
+
+        asprintf(&from, SYSTEM_DATA_UNIT_PATH "/%s", fservice);
+        asprintf(&to, "%s/getty.target.wants/%s", arg_dest, tservice);
+
+        if (!from || !to) {
+                log_error("Out of memory");
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        mkdir_parents(to, 0755);
+
+        if ((r = symlink(from, to)) < 0) {
+                log_error("Failed to create symlink from %s to %s: %m", from, to);
+                r = -errno;
+        }
+
+finish:
+
+        free(from);
+        free(to);
+
+        return r;
+}
+
+int main(int argc, char *argv[]) {
+        int r = EXIT_SUCCESS;
+        char *active;
+
+        if (argc > 2) {
+                log_error("This program takes one or no arguments.");
+                return EXIT_FAILURE;
+        }
+
+        if (argc > 1)
+            arg_dest = argv[1];
+
+        log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
+        log_parse_environment();
+        log_open();
+
+        if (detect_container(NULL) > 0) {
+                log_debug("Automatic adding console shell.");
+
+                if (add_symlink("console-shell.service", "console-shell.service") < 0)
+                        r = EXIT_FAILURE;
+
+                /* Don't add any further magic if we are in a container */
+                goto finish;
+        }
+
+        if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
+                const char *tty;
+
+                truncate_nl(active);
+                if ((tty = strrchr(active, ' ')))
+                        tty ++;
+                else
+                        tty = active;
+
+                /* Automatically add in a serial getty on the kernel
+                 * console */
+                if (!tty_is_vc(tty)) {
+                        char *n;
+
+                        /* We assume that gettys on virtual terminals are
+                         * started via manual configuration and do this magic
+                         * only for non-VC terminals. */
+
+                        log_debug("Automatically adding serial getty for /dev/%s.", tty);
+
+                        if (!(n = unit_name_replace_instance("serial-getty@.service", tty)) ||
+                            add_symlink("serial-getty@.service", n) < 0)
+                                r = EXIT_FAILURE;
+
+                        free(n);
+                }
+
+                free(active);
+        }
+
+        /* Automatically add in a serial getty on the first
+         * virtualizer console */
+        if (access("/sys/class/tty/hvc0", F_OK) == 0) {
+                log_debug("Automatic adding serial getty for hvc0.");
+
+                if (add_symlink("serial-getty@.service", "serial-getty@hvc0.service") < 0)
+                        r = EXIT_FAILURE;
+        }
+
+finish:
+        return r;
+}