From ab73d9f5258a202d0c2a514688091be4db6622e0 Mon Sep 17 00:00:00 2001
From: Colin Walters <walters@verbum.org>
Date: Tue, 6 Aug 2019 01:59:38 +0000
Subject: [PATCH] admin/init-fs: Add a --modern switch

This skips creating the default stuff in the physical sysroot.
I don't recall why I did that to be honest; it originated with
the first commit of this file.  It might not have ever been
necessary.

In any case, it's not necessary now with Fedora CoreOS, so
prune it and let's have a clean `/`.

Keep the old behavior by default though to avoid breaking anyone.

Closes: #1894
Approved by: ajeddeloh
---
 src/ostree/ot-admin-builtin-init-fs.c | 48 ++++++++++++++++++---------
 tests/admin-test.sh                   | 12 +++++--
 2 files changed, 42 insertions(+), 18 deletions(-)

diff --git a/src/ostree/ot-admin-builtin-init-fs.c b/src/ostree/ot-admin-builtin-init-fs.c
index cca63a62..cb1e1b69 100644
--- a/src/ostree/ot-admin-builtin-init-fs.c
+++ b/src/ostree/ot-admin-builtin-init-fs.c
@@ -30,7 +30,10 @@
 
 #include <glib/gi18n.h>
 
+static gboolean opt_modern;
+
 static GOptionEntry options[] = {
+  { "modern", 0, 0, G_OPTION_ARG_NONE, &opt_modern, "Only create /boot and /ostree", NULL },
   { NULL }
 };
 
@@ -58,26 +61,39 @@ ot_admin_builtin_init_fs (int argc, char **argv, OstreeCommandInvocation *invoca
   if (!glnx_opendirat (AT_FDCWD, sysroot_path, TRUE, &root_dfd, error))
     return FALSE;
 
-  const char *normal_toplevels[] = {"boot", "dev", "home", "proc", "run", "sys"};
-  for (guint i = 0; i < G_N_ELEMENTS (normal_toplevels); i++)
+  /* It's common to want to mount this outside of a deployment as well */
+  if (!glnx_shutil_mkdir_p_at (root_dfd, "boot", 0755, cancellable, error))
+    return FALSE;
+
+  /* See https://github.com/coreos/coreos-assembler/pull/688
+   * For Fedora CoreOS at least, we have this now to the point where we don't
+   * need this stuff in the physical sysroot.  I'm not sure we ever really did,
+   * but to be conservative, make it opt-in to the new model of just boot/ and ostree/.
+   */
+  if (!opt_modern)
     {
-      if (!glnx_shutil_mkdir_p_at (root_dfd, normal_toplevels[i], 0755,
-                                   cancellable, error))
+      const char *traditional_toplevels[] = {"boot", "dev", "home", "proc", "run", "sys"};
+      for (guint i = 0; i < G_N_ELEMENTS (traditional_toplevels); i++)
+        {
+          if (!glnx_shutil_mkdir_p_at (root_dfd, traditional_toplevels[i], 0755,
+                                      cancellable, error))
+            return FALSE;
+        }
+
+      if (!glnx_shutil_mkdir_p_at (root_dfd, "root", 0700,
+                                  cancellable, error))
         return FALSE;
+
+      if (!glnx_shutil_mkdir_p_at (root_dfd, "tmp", 01777,
+                                  cancellable, error))
+        return FALSE;
+      if (fchmodat (root_dfd, "tmp", 01777, 0) == -1)
+        {
+          glnx_set_prefix_error_from_errno (error, "chmod: %s", "tmp");
+          return FALSE;
+        }
     }
 
-  if (!glnx_shutil_mkdir_p_at (root_dfd, "root", 0700,
-                               cancellable, error))
-    return FALSE;
-
-  if (!glnx_shutil_mkdir_p_at (root_dfd, "tmp", 01777,
-                               cancellable, error))
-    return FALSE;
-  if (fchmodat (root_dfd, "tmp", 01777, 0) == -1)
-    {
-      glnx_set_prefix_error_from_errno (error, "chmod: %s", "tmp");
-      return FALSE;
-    }
   g_autoptr(GFile) dir = g_file_new_for_path (sysroot_path);
   g_autoptr(OstreeSysroot) sysroot = ostree_sysroot_new (dir);
   if (!ostree_sysroot_ensure_initialized (sysroot, cancellable, error))
diff --git a/tests/admin-test.sh b/tests/admin-test.sh
index 31e969c2..0defebc0 100644
--- a/tests/admin-test.sh
+++ b/tests/admin-test.sh
@@ -21,7 +21,15 @@
 
 set -euo pipefail
 
-echo "1..$((26 + ${extra_admin_tests:-0}))"
+echo "1..$((27 + ${extra_admin_tests:-0}))"
+
+mkdir sysrootmin
+${CMD_PREFIX} ostree admin init-fs --modern sysrootmin
+assert_has_dir sysrootmin/boot
+assert_has_dir sysrootmin/ostree/repo
+assert_not_has_dir sysrootmin/home
+rm sysrootmin -rf
+echo "ok init-fs --modern"
 
 function validate_bootloader() {
     cd ${test_tmpdir};
@@ -48,7 +56,7 @@ orig_mtime=$(stat -c '%.Y' sysroot/ostree/deploy)
 ${CMD_PREFIX} ostree --repo=sysroot/ostree/repo pull-local --remote=testos testos-repo testos/buildmaster/x86_64-runtime
 rev=$(${CMD_PREFIX} ostree --repo=sysroot/ostree/repo rev-parse testos/buildmaster/x86_64-runtime)
 export rev
-# This initial deployment gets kicked off with some kernel arguments 
+# This initial deployment gets kicked off with some kernel arguments
 ${CMD_PREFIX} ostree admin deploy --karg=root=LABEL=MOO --karg=quiet --os=testos testos:testos/buildmaster/x86_64-runtime
 new_mtime=$(stat -c '%.Y' sysroot/ostree/deploy)
 assert_not_streq "${orig_mtime}" "${new_mtime}"