From 2494dc196199ade968c817d68e6fe43ae851d3a3 Mon Sep 17 00:00:00 2001
From: Luca Boccassi <bluca@debian.org>
Date: Thu, 12 Sep 2024 18:46:04 +0200
Subject: [PATCH] core: do not fail if ignorable img.v/ vpick dir is empty

If the vpick directory is configured to be ignored if missing, do not
fail and just skip ahead.

Follow-up for 5e79dd96a88
Follow-up for 622efc544dc

(cherry picked from commit 00f546e25e8e46e5e289e1f2fc2ed3dcc6999223)
---
 src/core/namespace.c                  | 19 +++++++++++++------
 test/units/TEST-50-DISSECT.dissect.sh | 14 ++++++++------
 2 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/src/core/namespace.c b/src/core/namespace.c
index b92bb012ee..77bca0b6f4 100644
--- a/src/core/namespace.c
+++ b/src/core/namespace.c
@@ -513,11 +513,15 @@ static int append_extensions(
                               &result);
                 if (r < 0)
                         return r;
-                if (!result.path)
+                if (!result.path) {
+                        if (m->ignore_enoent)
+                                continue;
+
                         return log_debug_errno(
                                         SYNTHETIC_ERRNO(ENOENT),
                                         "No matching entry in .v/ directory %s found.",
                                         m->source);
+                }
 
                 if (asprintf(&mount_point, "%s/%zu", extension_dir, i) < 0)
                         return -ENOMEM;
@@ -555,10 +559,6 @@ static int append_extensions(
                 const char *e = *extension_directory;
                 bool ignore_enoent = false;
 
-                /* Pick up the counter where the ExtensionImages left it. */
-                if (asprintf(&mount_point, "%s/%zu", extension_dir, n++) < 0)
-                        return -ENOMEM;
-
                 /* Look for any prefixes */
                 if (startswith(e, "-")) {
                         e++;
@@ -576,11 +576,18 @@ static int append_extensions(
                               &result);
                 if (r < 0)
                         return r;
-                if (!result.path)
+                if (!result.path) {
+                        if (ignore_enoent)
+                                continue;
+
                         return log_debug_errno(
                                         SYNTHETIC_ERRNO(ENOENT),
                                         "No matching entry in .v/ directory %s found.",
                                         e);
+                }
+                /* Pick up the counter where the ExtensionImages left it. */
+                if (asprintf(&mount_point, "%s/%zu", extension_dir, n++) < 0)
+                        return -ENOMEM;
 
                 for (size_t j = 0; hierarchies && hierarchies[j]; ++j) {
                         char *prefixed_hierarchy = path_join(mount_point, hierarchies[j]);
diff --git a/test/units/TEST-50-DISSECT.dissect.sh b/test/units/TEST-50-DISSECT.dissect.sh
index 563206ce7e..6c79262c2d 100755
--- a/test/units/TEST-50-DISSECT.dissect.sh
+++ b/test/units/TEST-50-DISSECT.dissect.sh
@@ -443,14 +443,15 @@ systemctl is-active testservice-50e.service
 # Check vpick support in ExtensionImages=
 VBASE="vtest$RANDOM"
 VDIR="/tmp/$VBASE.v"
-mkdir "$VDIR"
+EMPTY_VDIR="/tmp/$VBASE-empty.v"
+mkdir "$VDIR" "$EMPTY_VDIR"
 
 ln -s /tmp/app0.raw "$VDIR/${VBASE}_0.raw"
 ln -s /tmp/app1.raw "$VDIR/${VBASE}_1.raw"
 
-systemd-run -P -p ExtensionImages="$VDIR" bash -c '/opt/script1.sh | grep ID'
+systemd-run -P -p ExtensionImages="$VDIR -$EMPTY_VDIR" bash -c '/opt/script1.sh | grep ID'
 
-rm -rf "$VDIR"
+rm -rf "$VDIR" "$EMPTY_VDIR"
 
 # ExtensionDirectories will set up an overlay
 mkdir -p "$IMAGE_DIR/app0" "$IMAGE_DIR/app1" "$IMAGE_DIR/app-nodistro" "$IMAGE_DIR/service-scoped-test"
@@ -529,14 +530,15 @@ systemctl is-active testservice-50f.service
 # Check vpick support in ExtensionDirectories=
 VBASE="vtest$RANDOM"
 VDIR="/tmp/$VBASE.v"
-mkdir "$VDIR"
+EMPTY_VDIR="/tmp/$VBASE-empty.v"
+mkdir "$VDIR" "$EMPTY_VDIR"
 
 ln -s "$IMAGE_DIR/app0" "$VDIR/${VBASE}_0"
 ln -s "$IMAGE_DIR/app1" "$VDIR/${VBASE}_1"
 
-systemd-run -P --property ExtensionDirectories="$VDIR" cat /opt/script1.sh | grep -q -F "extension-release.app2"
+systemd-run -P --property ExtensionDirectories="$VDIR -$EMPTY_VDIR" cat /opt/script1.sh | grep -q -F "extension-release.app2"
 
-rm -rf "$VDIR"
+rm -rf "$VDIR" "$EMPTY_VDIR"
 
 systemd-dissect --umount "$IMAGE_DIR/app0"
 systemd-dissect --umount "$IMAGE_DIR/app1"
-- 
2.25.1