1 files changed, 166 insertions, 0 deletions
diff --git a/inhibit-screensaver.c b/inhibit-screensaver.c
new file mode 100644
index 0000000..08cc1e1
--- /dev/null
+++ b/inhibit-screensaver.c
@@ -0,0 +1,166 @@
+// based on code from VLC
+// https://github.com/videolan/vlc/blob/734a505509828c3333067ea6be174f3a6525e486/modules/misc/inhibit/dbus.c
+
+#include <dbus/dbus.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+enum inhibit_api
+{
+    INVALID = 0,
+    FDO_SS, /**< KDE >= 4 and GNOME >= 3.10 */
+    FDO_PM, /**< KDE and GNOME <= 2.26 */
+    MATE,  /**< >= 1.0 */
+    GNOME, /**< GNOME 2.26..3.4 */
+};
+
+#define MAX_API (GNOME+1)
+
+/* Currently, all services have identical service and interface names. */
+static const char dbus_service[][40] =
+{
+    [INVALID] = { 0 },
+    [FDO_SS] = "org.freedesktop.ScreenSaver",
+    [FDO_PM] = "org.freedesktop.PowerManagement.Inhibit",
+    [MATE]   = "org.mate.SessionManager",
+    [GNOME]  = "org.gnome.SessionManager",
+};
+
+static const char dbus_path[][33] =
+{
+    [INVALID] = { 0 },
+    [FDO_SS] = "/ScreenSaver",
+    [FDO_PM] = "/org/freedesktop/PowerManagement",
+    [MATE]   = "/org/mate/SessionManager",
+    [GNOME]  = "/org/gnome/SessionManager",
+};
+
+static const char dbus_method_uninhibit[][10] =
+{
+    [INVALID] = { 0 },
+    [FDO_SS] = "UnInhibit",
+    [FDO_PM] = "UnInhibit",
+    [MATE]   = "Uninhibit",
+    [GNOME]  = "Uninhibit",
+};
+
+int main(int argc, char **argv) {
+    if (argc != 3) {
+        puts("usage: inhibit-screensaver APPLICATION REASON");
+        exit(1);
+    }
+
+    DBusConnection *conn;
+    dbus_uint32_t cookie = 0;
+    enum inhibit_api api = INVALID;
+
+    DBusError err;
+    dbus_error_init(&err);
+
+    conn = dbus_bus_get_private(DBUS_BUS_SESSION, &err);
+    if (conn == NULL) {
+        fprintf(stderr, "cannot connect to session bus: %s\n", err.message);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    for (unsigned i = 1; i < MAX_API; i++) {
+        if (dbus_bus_name_has_owner(conn, dbus_service[i], NULL)) {
+            api = i;
+            break;
+        }
+    }
+
+    if (!api) {
+        fprintf(stderr, "cannot find screensaver dbus name\n");
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    dbus_bool_t ret;
+
+    DBusMessage *msg = dbus_message_new_method_call(dbus_service[api], dbus_path[api], dbus_service[api], "Inhibit");
+    if (!msg) {
+        fputs("cannot create dbus message", stderr);
+        exit(1);
+    }
+
+    const char *app = argv[1];
+    const char *reason = argv[2];
+
+    switch (api)
+    {
+        case MATE:
+        case GNOME:
+        {
+            dbus_uint32_t xid = 0; // FIXME ?
+            dbus_uint32_t gflags = 0xC;
+
+            ret = dbus_message_append_args(msg, DBUS_TYPE_STRING, &app,
+                                                DBUS_TYPE_UINT32, &xid,
+                                                DBUS_TYPE_STRING, &reason,
+                                                DBUS_TYPE_UINT32, &gflags,
+                                                DBUS_TYPE_INVALID);
+            break;
+        }
+        default:
+            ret = dbus_message_append_args(msg, DBUS_TYPE_STRING, &app,
+                                                DBUS_TYPE_STRING, &reason,
+                                                DBUS_TYPE_INVALID);
+            break;
+    }
+
+    if (!ret) {
+        fputs("cannot create dbus Inhibit message (OOM?)", stderr);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    DBusMessage *reply = dbus_connection_send_with_reply_and_block(conn, msg, DBUS_TIMEOUT_INFINITE, &err);
+
+    dbus_message_unref(msg);
+
+    if (!reply) {
+        fprintf(stderr, "cannot send dbus Inhibit message: %s\n", err.message);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    if (!dbus_message_get_args(reply, &err,
+                DBUS_TYPE_UINT32, &cookie,
+                DBUS_TYPE_INVALID)) {
+        fprintf(stderr, "cannot parse dbus Inhibit reply: %s\n", err.message);
+        // dbus_message_unref(reply);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    dbus_message_unref(reply);
+
+    char buf;
+    while (fread(&buf, 1, 1, stdin) == 1)
+        ;
+
+    msg = dbus_message_new_method_call(dbus_service[api], dbus_path[api], dbus_service[api], dbus_method_uninhibit[api]);
+    if (!msg) {
+        fputs("cannot create dbus message", stderr);
+        exit(1);
+    }
+
+    if (!dbus_message_append_args(msg, DBUS_TYPE_UINT32, &cookie, DBUS_TYPE_INVALID)) {
+        fprintf(stderr, "cannot create dbus UnInhibit message: %s\n", err.message);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    if (!dbus_connection_send(conn, msg, NULL)) {
+        fputs("cannot send dbus UnInhibit message", stderr);
+        // dbus_error_free(&err);
+        exit(1);
+    }
+
+    dbus_connection_flush(conn);
+    dbus_connection_close(conn);
+    dbus_connection_unref(conn);
+    return 0;
+}