libpriv/importer: move tmpfiles.d entries buffering to Rust

This moves the RPM importer buffering logic for tmpfiles.d entries
to Rust.

rust/src/importer.rs

@@ -61,6 +61,8 @@ pub struct RpmImporter {
     ///  - [K] absolute full path of the file
     ///  - [V] iterator index in RPM header for this file
     rpmfi_overrides: HashMap<String, u64>,
+    /// Filepaths translated to tmpfiles.d entries.
+    tmpfiles_entries: Vec<String>,
 }
 
 /// Build a new RPM importer for a given package.
@@ -102,6 +104,7 @@ impl RpmImporter {
             pkg_name: pkg_name.to_string(),
             varlib_direntries: BTreeSet::new(),
             rpmfi_overrides: HashMap::new(),
+            tmpfiles_entries: vec![],
         };
         Ok(importer)
     }
@@ -176,7 +179,7 @@ impl RpmImporter {
     /// Format tmpfiles.d lines for symlinked entries.
     // NOTE(lucab): destinations (dirname) can't be quoted as systemd just
     // parses the remainder of the line, and doesn't expand quotes.
-    pub fn tmpfiles_symlink_entries(&self) -> Vec<String> {
+    fn tmpfiles_symlink_entries(&self) -> Vec<String> {
         // /opt/ symlinks
         let opt_entries = self.opt_direntries.iter().map(|dirname| {
             let quoted = crate::maybe_shell_quote(&format!("/opt/{dirname}"));
@@ -251,6 +254,43 @@ impl RpmImporter {
             x => unreachable!("unknown commit result '{}' for path '{}'", x, path),
         }
     }
+
+    /// Translate a filepath to an equivalent tmpfiles.d line.
+    pub fn translate_to_tmpfiles_entry(
+        &mut self,
+        abs_path: &str,
+        mut file_info: Pin<&mut crate::FFIGFileInfo>,
+        username: &str,
+        groupname: &str,
+    ) -> CxxResult<()> {
+        let file_info = file_info.gobj_wrap();
+        let entry = translate_to_tmpfiles_d(abs_path, &file_info, username, groupname)?;
+        self.tmpfiles_entries.push(entry);
+        Ok(())
+    }
+
+    /// Return whether this RPM has any auto-translated tmpfiles.d entries.
+    pub fn has_tmpfiles_entries(&self) -> bool {
+        self.tmpfiles_entries
+            .len()
+            .saturating_add(self.opt_direntries.len())
+            .saturating_add(self.varlib_direntries.len())
+            > 0
+    }
+
+    /// Serialize all tmpfiles.d entries as a single configuration fragment.
+    pub fn serialize_tmpfiles_content(&self) -> String {
+        let mut buf = String::new();
+
+        let symlink_entries = self.tmpfiles_symlink_entries();
+        let all_entries = symlink_entries.iter().chain(self.tmpfiles_entries.iter());
+
+        for entry in all_entries {
+            buf.push_str(&entry);
+            buf.push('\n');
+        }
+        buf
+    }
 }
 
 /// Canonicalize a path, e.g. replace `//` with `/` and `././` with `./`.

rust/src/lib.rs

@@ -349,7 +349,6 @@ pub mod ffi {
         fn handle_translate_pathname(self: &mut RpmImporter, path: &str) -> String;
         fn ostree_branch(self: &RpmImporter) -> String;
         fn pkg_name(self: &RpmImporter) -> String;
-        fn tmpfiles_symlink_entries(self: &RpmImporter) -> Vec<String>;
         fn doc_files_are_filtered(self: &RpmImporter) -> bool;
         fn doc_files_insert(self: &mut RpmImporter, path: &str);
         fn doc_files_contains(self: &RpmImporter, path: &str) -> bool;
@@ -363,6 +362,15 @@ pub mod ffi {
             path: &str,
             mut file_info: Pin<&mut GFileInfo>,
         ) -> Result<bool>;
+        fn translate_to_tmpfiles_entry(
+            self: &mut RpmImporter,
+            abs_path: &str,
+            mut file_info: Pin<&mut GFileInfo>,
+            username: &str,
+            groupname: &str,
+        ) -> Result<()>;
+        fn has_tmpfiles_entries(self: &RpmImporter) -> bool;
+        fn serialize_tmpfiles_content(self: &RpmImporter) -> String;
 
         fn tmpfiles_translate(
             abs_path: &str,

src/libpriv/rpmostree-importer.cxx

@@ -61,7 +61,6 @@ struct RpmOstreeImporter
   Header hdr;
   rpmfi fi;
   off_t cpio_offset;
-  GString *tmpfiles_d;
   DnfPackage *pkg;
 
   std::optional<rust::Box<rpmostreecxx::RpmImporter> > importer_rs;
@@ -80,7 +79,6 @@ rpmostree_importer_finalize (GObject *object)
   if (self->fi)
     (void)rpmfiFree (self->fi);
   glnx_close_fd (&self->fd);
-  g_string_free (self->tmpfiles_d, TRUE);
   g_clear_object (&self->repo);
   g_clear_object (&self->sepolicy);
 
@@ -101,7 +99,6 @@ static void
 rpmostree_importer_init (RpmOstreeImporter *self)
 {
   self->fd = -1;
-  self->tmpfiles_d = g_string_new ("");
   self->importer_rs = std::nullopt;
 }
 
@@ -497,13 +494,9 @@ compose_filter_cb (OstreeRepo *repo, const char *path, GFileInfo *file_info, gpo
       const char *group = NULL;
       get_rpmfi_override (self, path, &user, &group, NULL, NULL);
 
-      auto entry = ROSCXX_VAL (
-          tmpfiles_translate (path, *file_info, user ?: "root", group ?: "root"), error);
-      if (entry.has_value ())
-        {
-          g_string_append (self->tmpfiles_d, entry.value ().c_str ());
-          g_string_append_c (self->tmpfiles_d, '\n');
-        }
+      CXX ((*self->importer_rs)
+               ->translate_to_tmpfiles_entry (path, *file_info, user ?: "root", group ?: "root"),
+           error);
 
       return OSTREE_REPO_COMMIT_FILTER_SKIP;
     }
@@ -607,9 +600,6 @@ import_rpm_to_repo (RpmOstreeImporter *self, char **out_csum, char **out_metadat
       return FALSE;
     }
 
-  for (auto &line : (*self->importer_rs)->tmpfiles_symlink_entries ())
-    g_string_append_printf (self->tmpfiles_d, "%s\n", line.c_str ());
-
   /* Handle any data we've accumulated to write to tmpfiles.d.
    * I originally tried to do this entirely in memory but things
    * like selinux labeling only happen as callbacks out of using
@@ -618,8 +608,9 @@ import_rpm_to_repo (RpmOstreeImporter *self, char **out_csum, char **out_metadat
   g_auto (GLnxTmpDir) tmpdir = {
     0,
   };
-  if (self->tmpfiles_d->len > 0)
+  if ((*self->importer_rs)->has_tmpfiles_entries ())
     {
+      auto content = (*self->importer_rs)->serialize_tmpfiles_content ();
       auto pkg_name = (*self->importer_rs)->pkg_name ();
 
       if (!glnx_mkdtemp ("rpm-ostree-import.XXXXXX", 0700, &tmpdir, error))
@@ -628,8 +619,8 @@ import_rpm_to_repo (RpmOstreeImporter *self, char **out_csum, char **out_metadat
         return FALSE;
       if (!glnx_file_replace_contents_at (
               tmpdir.fd, glnx_strjoina ("usr/lib/tmpfiles.d/", "pkg-", pkg_name.c_str (), ".conf"),
-              (guint8 *)self->tmpfiles_d->str, self->tmpfiles_d->len, GLNX_FILE_REPLACE_NODATASYNC,
-              cancellable, error))
+              (guint8 *)content.data (), content.size (), GLNX_FILE_REPLACE_NODATASYNC, cancellable,
+              error))
         return FALSE;
 
       if (!ostree_repo_write_dfd_to_mtree (repo, tmpdir.fd, ".", mtree, modifier, cancellable,