From 8c533c5aab948fff3ebef12a6d965c9303302c35 Mon Sep 17 00:00:00 2001
From: Luca BRUNO <luca.bruno@coreos.com>
Date: Thu, 17 Jun 2021 08:30:00 +0000
Subject: [PATCH 1/3] builtin/tree: inject _dbpath macro file in postprocessing
 step

This wires the _dbpath macro injection logic to `compose postprocess`,
in order to make sure that the rpm configuration in the commit
matches the location of the rpmdb database.
---
 rust/src/composepost.rs               | 12 +++++++++---
 rust/src/lib.rs                       |  1 +
 src/libpriv/rpmostree-postprocess.cxx |  3 +++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/rust/src/composepost.rs b/rust/src/composepost.rs
index c63ca8fa5..4e000a97e 100644
--- a/rust/src/composepost.rs
+++ b/rust/src/composepost.rs
@@ -172,9 +172,15 @@ fn postprocess_presets(rootfs_dfd: &openat::Dir) -> Result<()> {
     Ok(())
 }
 
-// We keep hitting issues with the ostree-remount preset not being
-// enabled; let's just do this rather than trying to propagate the
-// preset everywhere.
+/// Write an RPM macro file to ensure the rpmdb path is set on the client side.
+pub fn compose_postprocess_rpm_macro(rootfs_dfd: i32) -> CxxResult<()> {
+    let rootfs = &crate::ffiutil::ffi_view_openat_dir(rootfs_dfd);
+    postprocess_rpm_macro(rootfs)?;
+    Ok(())
+}
+
+/// Ensure our own `_dbpath` macro exists in the tree.
+#[context("Writing _dbpath RPM macro")]
 fn postprocess_rpm_macro(rootfs_dfd: &openat::Dir) -> Result<()> {
     let rpm_macros_dir = "usr/lib/rpm/macros.d";
     rootfs_dfd.ensure_dir_all(rpm_macros_dir, 0o755)?;
diff --git a/rust/src/lib.rs b/rust/src/lib.rs
index 4c328fe4c..658a7fa95 100644
--- a/rust/src/lib.rs
+++ b/rust/src/lib.rs
@@ -160,6 +160,7 @@ pub mod ffi {
             rootfs_dfd: i32,
             cancellable: Pin<&mut GCancellable>,
         ) -> Result<()>;
+        fn compose_postprocess_rpm_macro(rootfs_dfd: i32) -> Result<()>;
     }
 
     // A grab-bag of metadata from the deployment's ostree commit
diff --git a/src/libpriv/rpmostree-postprocess.cxx b/src/libpriv/rpmostree-postprocess.cxx
index 42aa0b569..781c3a15c 100644
--- a/src/libpriv/rpmostree-postprocess.cxx
+++ b/src/libpriv/rpmostree-postprocess.cxx
@@ -649,6 +649,9 @@ rpmostree_rootfs_postprocess_common (int           rootfs_fd,
         }
     }
 
+  /* Make sure there is an RPM macro in place pointing to the rpmdb in /usr */
+  rpmostreecxx::compose_postprocess_rpm_macro(rootfs_fd);
+
   if (!rpmostree_cleanup_leftover_rpmdb_files (rootfs_fd, cancellable, error))
     return FALSE;
 

From ac7c64428594726a5420b1c11d7b6d6a48ffc0a8 Mon Sep 17 00:00:00 2001
From: Luca BRUNO <luca.bruno@coreos.com>
Date: Sun, 13 Jun 2021 13:50:39 +0000
Subject: [PATCH 2/3] libpriv/core: set _dbpath macro in dnf context

This ensures that the `_dbpath` macro is always in all dnf contexts,
in order to use the rpmdb under /usr.
Setting it explicitly makes sure that there is no logic implicitly
relying on host configuration. This is particularly relevant in
server-side compose cases, which are more likely to be running in
an environment without rpm-ostree macro file.
---
 src/libpriv/rpmostree-core.cxx | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/libpriv/rpmostree-core.cxx b/src/libpriv/rpmostree-core.cxx
index 12381e20e..ab0e0ef54 100644
--- a/src/libpriv/rpmostree-core.cxx
+++ b/src/libpriv/rpmostree-core.cxx
@@ -379,6 +379,9 @@ rpmostree_context_new_client (OstreeRepo   *repo)
   dnf_context_set_zchunk (self->dnfctx, FALSE);
 #endif
 
+  /* The rpmdb is at /usr/share/rpm */
+  dnf_context_set_rpm_macro (self->dnfctx, "_dbpath", "/" RPMOSTREE_RPMDB_LOCATION);
+
   return self;
 }
 

From bfdebee9f8b0bf7c4488bcfe723b12faed784da8 Mon Sep 17 00:00:00 2001
From: Colin Walters <walters@verbum.org>
Date: Fri, 11 Jun 2021 15:33:30 +0000
Subject: [PATCH 3/3] builtin/tree: explicitly set _dbpath macro in global
 libdnf initialization

This ensures that the `_dbpath` macro is always in all dnf contexts,
in order to use the rpmdb under /usr.
Setting it explicitly makes sure that there is no logic implicitly
relying on host configuration. This is particularly relevant in
server-side compose cases, which are more likely to be running in
an environment without rpm-ostree macro file.
---
 src/app/rpmostree-compose-builtin-tree.cxx |  2 ++
 src/libpriv/rpmostree-core.cxx             | 32 +++++++++++++++++++---
 src/libpriv/rpmostree-core.h               |  4 +++
 src/libpriv/rpmostree-rpm-util.cxx         |  2 ++
 4 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/src/app/rpmostree-compose-builtin-tree.cxx b/src/app/rpmostree-compose-builtin-tree.cxx
index 4d88ee95f..d6eef2c44 100644
--- a/src/app/rpmostree-compose-builtin-tree.cxx
+++ b/src/app/rpmostree-compose-builtin-tree.cxx
@@ -574,6 +574,8 @@ rpm_ostree_compose_context_new (const char    *treefile_pathstr,
 {
   g_autoptr(RpmOstreeTreeComposeContext) self = g_new0 (RpmOstreeTreeComposeContext, 1);
 
+  rpmostreecxx::core_libdnf_process_global_init();
+
   /* Init fds to -1 */
   self->workdir_dfd = self->rootfs_dfd = self->cachedir_dfd = -1;
   /* Test whether or not bwrap is going to work - we will fail inside e.g. a Docker
diff --git a/src/libpriv/rpmostree-core.cxx b/src/libpriv/rpmostree-core.cxx
index ab0e0ef54..e142ccd76 100644
--- a/src/libpriv/rpmostree-core.cxx
+++ b/src/libpriv/rpmostree-core.cxx
@@ -653,6 +653,32 @@ rpmostree_context_set_treespec (RpmOstreeContext *self, RpmOstreeTreespec *trees
     self->spec = (RpmOstreeTreespec*)g_object_ref (treespec);
 }
 
+namespace rpmostreecxx {
+// Sadly, like most of librpm, macros are a process-global state.
+// For rpm-ostree, the dbpath must be overriden.
+void
+core_libdnf_process_global_init()
+{
+  static gsize initialized = 0;
+
+  if (g_once_init_enter (&initialized))
+    {
+      g_autoptr(GError) error = NULL;
+      /* Fatally error out if this fails */
+      if (!dnf_context_globals_init (&error))
+        g_error ("%s", error->message);
+
+      /* This is what we use as default. Note we should be able to drop this in the
+       * future on the *client side* now that we inject a macro to set that value in our OSTrees.
+       */
+      free (rpmExpand ("%define _dbpath /" RPMOSTREE_RPMDB_LOCATION, NULL));
+
+      g_once_init_leave (&initialized, 1);
+    }
+}
+
+} /* namespace */
+
 /* Wraps `dnf_context_setup()`, and initializes state based on the treespec
  * @spec. Another way to say it is we pair `DnfContext` with an
  * `RpmOstreeTreespec`. For example, we handle "instlangs", set the rpmdb root
@@ -674,6 +700,8 @@ rpmostree_context_setup (RpmOstreeContext    *self,
   /* This exists (as a canonically empty dir) at least on RHEL7+ */
   static const char emptydir_path[] = "/usr/share/empty";
 
+  rpmostreecxx::core_libdnf_process_global_init();
+
   /* Auto-synthesize a spec for now; this will be removed */
   if (!self->spec)
     rpmostree_context_set_treespec (self, NULL);
@@ -710,10 +738,6 @@ rpmostree_context_setup (RpmOstreeContext    *self,
         dnf_context_set_rpm_macro (self->dnfctx, "_install_langs", instlangs.c_str());
     }
 
-  /* This is what we use as default. Note we should be able to drop this in the
-   * future now that we inject a macro to set that value in our OSTrees. */
-  dnf_context_set_rpm_macro (self->dnfctx, "_dbpath", "/" RPMOSTREE_RPMDB_LOCATION);
-
   /* Set the database backend only in the compose path.  It then becomes the default
    * for any client side layering.
    */
diff --git a/src/libpriv/rpmostree-core.h b/src/libpriv/rpmostree-core.h
index 1db1014cd..cea97028e 100644
--- a/src/libpriv/rpmostree-core.h
+++ b/src/libpriv/rpmostree-core.h
@@ -78,6 +78,10 @@ char* rpmostree_refspec_to_string (RpmOstreeRefspecType  reftype,
 char* rpmostree_refspec_canonicalize (const char           *orig_refspec,
                                       GError              **error);
 
+namespace rpmostreecxx {
+void core_libdnf_process_global_init();
+}
+
 RpmOstreeContext *rpmostree_context_new_client (OstreeRepo   *repo);
 
 RpmOstreeContext *rpmostree_context_new_compose (int basedir_dfd,
diff --git a/src/libpriv/rpmostree-rpm-util.cxx b/src/libpriv/rpmostree-rpm-util.cxx
index 57bdda4ed..19640b864 100644
--- a/src/libpriv/rpmostree-rpm-util.cxx
+++ b/src/libpriv/rpmostree-rpm-util.cxx
@@ -851,6 +851,8 @@ get_sack_for_root (int               dfd,
   GLNX_AUTO_PREFIX_ERROR ("Loading sack", error);
   g_assert (out_sack != NULL);
 
+  rpmostreecxx::core_libdnf_process_global_init();
+
   g_autofree char *fullpath = glnx_fdrel_abspath (dfd, path);
 
   g_autoptr(DnfSack) sack = dnf_sack_new ();