1 files changed, 111 insertions, 0 deletions
diff --git a/src/ac-power.c b/src/ac-power.c
new file mode 100644
index 0000000000..24a68e717e
--- /dev/null
+++ b/src/ac-power.c
@@ -0,0 +1,111 @@
+/*-*- 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 <stdlib.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <string.h>
+#include <libudev.h>
+
+#include "util.h"
+
+static int on_ac_power(void) {
+        int r;
+
+        struct udev *udev;
+        struct udev_enumerate *e = NULL;
+        struct udev_list_entry *item = NULL, *first = NULL;
+        bool found_offline = false, found_online = false;
+
+        if (!(udev = udev_new())) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (!(e = udev_enumerate_new(udev))) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (udev_enumerate_add_match_subsystem(e, "power_supply") < 0) {
+                r = -EIO;
+                goto finish;
+        }
+
+        if (udev_enumerate_scan_devices(e) < 0) {
+                r = -EIO;
+                goto finish;
+        }
+
+        first = udev_enumerate_get_list_entry(e);
+        udev_list_entry_foreach(item, first) {
+                struct udev_device *d;
+                const char *type, *online;
+
+                if (!(d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item)))) {
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                if (!(type = udev_device_get_sysattr_value(d, "type")))
+                        goto next;
+
+                if (!streq(type, "Mains"))
+                        goto next;
+
+                if (!(online = udev_device_get_sysattr_value(d, "online")))
+                        goto next;
+
+                if (streq(online, "1")) {
+                        found_online = true;
+                        break;
+                } else if (streq(online, "0"))
+                        found_offline = true;
+
+        next:
+                udev_device_unref(d);
+        }
+
+        r = found_online || !found_offline;
+
+finish:
+        if (e)
+                udev_enumerate_unref(e);
+
+        if (udev)
+                udev_unref(udev);
+
+        return r;
+}
+
+int main(int argc, char *argv[]) {
+        int r;
+
+        /* This is mostly intended to be used for scripts which want
+         * to detect whether AC power is plugged in or not. */
+
+        if ((r = on_ac_power()) < 0) {
+                log_error("Failed to read AC status: %s", strerror(-r));
+                return EXIT_FAILURE;
+        }
+
+        return r == 0;
+}