init: add support for sysupgrades triggered from preinit

[project/procd.git] / sysupgrade.c

diff --git a/sysupgrade.c b/sysupgrade.c
new file mode 100644 (file)
index 0000000..30f1836
--- /dev/null
+++ b/sysupgrade.c
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2017 Matthias Schiffer <mschiffer@universe-factory.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program 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.
+ */
+
+
+#include "watchdog.h"
+#include "sysupgrade.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+void sysupgrade_exec_upgraded(const char *prefix, char *path, char *command)
+{
+       char *wdt_fd = watchdog_fd();
+       char *argv[] = { "/sbin/upgraded", NULL, NULL, NULL};
+
+       if (chroot(prefix)) {
+               fprintf(stderr, "Failed to chroot for upgraded exec.\n");
+               return;
+       }
+
+       argv[1] = path;
+       argv[2] = command;
+
+       if (wdt_fd) {
+               watchdog_set_cloexec(false);
+               setenv("WDTFD", wdt_fd, 1);
+       }
+       execvp(argv[0], argv);
+
+       /* Cleanup on failure */
+       fprintf(stderr, "Failed to exec upgraded.\n");
+       unsetenv("WDTFD");
+       watchdog_set_cloexec(true);
+       chroot(".");
+}