apply-live: Move client-side finish to Rust

Now that we have an RPM diff+printing binding, we can
move the client side postprocessing for `apply-live`
to Rust.

rust/src/lib.rs

@@ -199,6 +199,7 @@ pub mod ffi {
         ) -> Result<bool>;
         // FIXME/cxx make this Option<&str>
         fn transaction_apply_live(sysroot: Pin<&mut OstreeSysroot>, target: &str) -> Result<()>;
+        fn applylive_client_finish() -> Result<()>;
     }
 
     // passwd.rs
@@ -271,7 +272,13 @@ pub mod ffi {
         fn n_removed(&self) -> i32;
         fn n_added(&self) -> i32;
         fn n_modified(&self) -> i32;
+        fn rpmdb_diff(
+            repo: Pin<&mut OstreeRepo>,
+            src: &CxxString,
             dest: &CxxString,
+        ) -> Result<UniquePtr<RPMDiff>>;
+
+        fn print(&self);
     }
 
     unsafe extern "C++" {

rust/src/live.rs

@@ -340,6 +340,12 @@ fn rerun_tmpfiles() -> Result<()> {
     Ok(())
 }
 
+fn require_booted_deployment(sysroot: &ostree::Sysroot) -> Result<ostree::Deployment> {
+    sysroot
+        .get_booted_deployment()
+        .ok_or_else(|| anyhow!("Not booted into an OSTree system"))
+}
+
 /// Implementation of `rpm-ostree ex apply-live`.
 pub(crate) fn transaction_apply_live(
     mut sysroot: Pin<&mut crate::ffi::OstreeSysroot>,
@@ -353,11 +359,7 @@ pub(crate) fn transaction_apply_live(
     };
     let repo = &sysroot.repo().expect("repo");
 
-    let booted = if let Some(b) = sysroot.get_booted_deployment() {
-        b
-    } else {
-        return Err(anyhow!("Not booted into an OSTree system").into());
-    };
+    let booted = require_booted_deployment(sysroot)?;
     let osname = booted.get_osname().expect("osname");
     let booted_commit = booted.get_csum().expect("csum");
     let booted_commit = booted_commit.as_str();
@@ -482,6 +484,42 @@ pub(crate) fn transaction_apply_live(
     Ok(())
 }
 
+pub(crate) fn applylive_client_finish() -> CxxResult<()> {
+    let cancellable = gio::NONE_CANCELLABLE;
+    let sysroot = &ostree::Sysroot::new_default();
+    sysroot.load(cancellable)?;
+    let repo = &sysroot.get_repo(cancellable)?;
+    let booted = &require_booted_deployment(sysroot)?;
+    let booted_commit = booted.get_csum().expect("csum");
+    let booted_commit = booted_commit.as_str();
+
+    let live_state = get_live_state(booted)?
+        .ok_or_else(|| anyhow!("Failed to find expected apply-live state"))?;
+
+    // It might happen that the live target commit was GC'd somehow; we're not writing
+    // an explicit ref for it.  In that case skip the diff.
+    if !repo.has_object(
+        ostree::ObjectType::Commit,
+        live_state.commit.as_str(),
+        cancellable,
+    )? {
+        return Ok(());
+    }
+
+    let pkgdiff = {
+        cxx::let_cxx_string!(from = booted_commit);
+        cxx::let_cxx_string!(to = live_state.commit.as_str());
+        let repo = repo.gobj_rewrap();
+        crate::ffi::rpmdb_diff(repo, &from, &to).map_err(anyhow::Error::msg)?
+    };
+    pkgdiff.print();
+
+    crate::ffi::output_message(
+        "Successfully updated running filesystem tree; some services may need to be restarted.",
+    );
+    Ok(())
+}
+
 #[cfg(test)]
 mod test {
     use super::*;

src/app/rpmostree-builtin-applylive.cxx

@@ -112,45 +112,7 @@ rpmostree_ex_builtin_apply_live (int             argc,
                                                 error))
     return FALSE;
 
-  /* TODO - we compute all this client side right now for multiple reasons.
-   * - The diff printing code all lives on the client right now
-   * - We don't bind `rpmostree_output_message()` into Rust yet
-   * - We've historically accessed RPM diffs client side
-   */
-  g_autoptr(OstreeSysroot) sysroot = ostree_sysroot_new_default ();
-  if (!ostree_sysroot_load (sysroot, cancellable, error))
-    return FALSE;
-  g_autoptr(OstreeRepo) repo = NULL;
-  if (!ostree_sysroot_get_repo (sysroot, &repo, cancellable, error))
-    return FALSE;
-  OstreeDeployment *booted_deployment = ostree_sysroot_get_booted_deployment (sysroot);
-  g_assert (booted_deployment);
-  const char *booted_commit = ostree_deployment_get_csum (booted_deployment);
-
-  auto live_state = rpmostreecxx::get_live_apply_state(*sysroot, *booted_deployment);
-  g_assert (live_state.commit.length() > 0);
-
-  gboolean have_target = FALSE;
-  if (!ostree_repo_has_object (repo, OSTREE_OBJECT_TYPE_COMMIT, live_state.commit.c_str(), &have_target, NULL, error))
-    return FALSE;
-  /* It might happen that the live target commit was GC'd somehow; we're not writing
-   * an explicit ref for it.  In that case skip the diff.
-   */
-  if (have_target)
-    {
-      g_autoptr(GPtrArray) removed = NULL;
-      g_autoptr(GPtrArray) added = NULL;
-      g_autoptr(GPtrArray) modified_old = NULL;
-      g_autoptr(GPtrArray) modified_new = NULL;
-      if (!rpm_ostree_db_diff (repo, booted_commit, live_state.commit.c_str(),
-                              &removed, &added, &modified_old, &modified_new,
-                              cancellable, error))
-        return FALSE;
-      rpmostree_diff_print_formatted (RPMOSTREE_DIFF_PRINT_FORMAT_FULL_MULTILINE, NULL, 0,
-                                      removed, added, modified_old, modified_new);
-    }
-
-  g_print ("Successfully updated running filesystem tree; some services may need to be restarted.\n");
+  rpmostreecxx::applylive_client_finish();
 
   return TRUE;
 }