client: Explicitly systemctl start rpm-ostreed if root, dump status

rust/src/client.rs

@@ -7,6 +7,7 @@ use crate::utils;
 use anyhow::{anyhow, Result};
 use gio::DBusProxyExt;
 use std::os::unix::io::IntoRawFd;
+use std::process::Command;
 
 /// The well-known bus name.
 const BUS_NAME: &str = "org.projectatomic.rpmostree1";
@@ -126,3 +127,29 @@ pub(crate) fn client_handle_fd_argument(arg: &str, arch: &str) -> CxxResult<Vec<
         Ok(Vec::new())
     }
 }
+
+/// Explicitly ensure the daemon is started via systemd, if possible.
+///
+/// This works around bugs from DBus activation, see
+/// https://github.com/coreos/rpm-ostree/pull/2932
+///
+/// Basically we load too much data before claiming the bus name,
+/// and dbus doesn't give us a useful error.  Instead, let's talk
+/// to systemd directly and use its client tools to scrape errors.
+pub(crate) fn client_start_daemon() -> CxxResult<()> {
+    let service = "rpm-ostreed.service";
+    // Assume non-root can't use systemd right now.
+    if !nix::unistd::getuid().is_root() {
+        return Ok(());
+    }
+    let res = Command::new("systemctl")
+        .args(&["--no-ask-password", "start", service])
+        .status()?;
+    if !res.success() {
+        let _ = Command::new("systemctl")
+            .args(&["status", service])
+            .status();
+        return Err(anyhow!("{}", res).into());
+    }
+    Ok(())
+}

rust/src/lib.rs

@@ -63,6 +63,7 @@ pub mod ffi {
 
     // client.rs
     extern "Rust" {
+        fn client_start_daemon() -> Result<()>;
         fn client_handle_fd_argument(arg: &str, arch: &str) -> Result<Vec<i32>>;
     }
 

src/app/rpmostree-clientlib.cxx

@@ -82,6 +82,8 @@ app_load_sysroot_impl (const char       *sysroot,
 {
   const char *bus_name = NULL;
 
+  rpmostreecxx::client_start_daemon();
+
   g_autoptr(GDBusConnection) connection = g_bus_get_sync (G_BUS_TYPE_SYSTEM, cancellable, error);
   if (!connection)
     return glnx_prefix_error (error, "Connecting to system bus");

tests/kolainst/nondestructive/misc.sh

@@ -106,6 +106,17 @@ mv /var/lib/rpm{.orig,}
 systemctl reset-failed rpm-ostreed
 echo "ok validated rpmdb"
 
+systemctl stop rpm-ostreed
+unshare -m /bin/bash -c 'mount -o remount,rw /boot && mkdir /boot/orig-loader && mv /boot/loader* /boot/orig-loader'
+if rpm-ostree status &>err.txt; then
+    fatal "started rpm-ostreed with no /boot/loader"
+fi
+assert_file_has_content_literal err.txt "Unexpected state: /run/ostree-booted found, but no /boot/loader directory"
+rm -f err.txt
+unshare -m /bin/bash -c 'mount -o remount,rw /boot && mv /boot/orig-loader/* /boot'
+systemctl restart rpm-ostreed
+echo "ok daemon statup failure gives useful error"
+
 rpm-ostree cleanup -p
 originpath=$(ostree admin --print-current-dir).origin
 unshare -m /bin/bash -c "mount -o remount,rw /sysroot && cp -a ${originpath}{,.orig} &&