Fix a crash when more than one thread tries to ensure the same package

This can happen when a package is itself an extra package of another, at the
same time being a valid application itself. This is probably a packaging bug,
but crashing isn't nice either.

2 files changed, 41 insertions, 4 deletions

diff --git a/libappstream-builder/asb-package.c b/libappstream-builder/asb-package.c
index d0e9d4f..7ca89c4 100644
--- a/libappstream-builder/asb-package.c
+++ b/libappstream-builder/asb-package.c
@@ -42,7 +42,9 @@ struct _AsbPackagePrivate
 	gboolean	 enabled;
 	gboolean	 is_open;
 	gchar		**filelist;
+	guint		 filelist_refcount;
 	GPtrArray	*deps;
+	guint		 deps_refcount;
 	gchar		*filename;
 	gchar		*basename;
 	gchar		*name;
@@ -966,6 +968,12 @@ asb_package_ensure (AsbPackage *pkg,
 			return FALSE;
 	}
 
+	/* this is recounted */
+	if (flags & ASB_PACKAGE_ENSURE_DEPS)
+		priv->deps_refcount++;
+	if (flags & ASB_PACKAGE_ENSURE_FILES)
+		priv->filelist_refcount++;
+
 	/* clear flags */
 	if (priv->name != NULL)
 		flags &= ~ASB_PACKAGE_ENSURE_NEVRA;
@@ -1007,11 +1015,17 @@ void
 asb_package_clear (AsbPackage *pkg, AsbPackageEnsureFlags flags)
 {
 	AsbPackagePrivate *priv = GET_PRIVATE (pkg);
-	if (flags & ASB_PACKAGE_ENSURE_DEPS)
-		g_ptr_array_set_size (priv->deps, 0);
+
+	/* this is recounted */
+	if (flags & ASB_PACKAGE_ENSURE_DEPS) {
+		if (priv->deps_refcount > 0 && --priv->deps_refcount == 0)
+			g_ptr_array_set_size (priv->deps, 0);
+	}
 	if (flags & ASB_PACKAGE_ENSURE_FILES) {
-		g_strfreev (priv->filelist);
-		priv->filelist = NULL;
+		if (priv->filelist_refcount > 0 && --priv->filelist_refcount == 0) {
+			g_strfreev (priv->filelist);
+			priv->filelist = NULL;
+		}
 	}
 }
 
diff --git a/libappstream-builder/asb-self-test.c b/libappstream-builder/asb-self-test.c
index b196cba..687bb21 100644
--- a/libappstream-builder/asb-self-test.c
+++ b/libappstream-builder/asb-self-test.c
@@ -155,6 +155,29 @@ asb_test_package_rpm_func (void)
 	asb_package_set_config (pkg, "test", "dave2");
 	g_assert_cmpstr (asb_package_get_config (pkg, "test"), ==, "dave2");
 
+	/* clear */
+	asb_package_clear (pkg,
+			   ASB_PACKAGE_ENSURE_DEPS |
+			   ASB_PACKAGE_ENSURE_FILES);
+	g_assert (asb_package_get_filelist (pkg) == NULL);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 0);
+
+	/* clear, ensure, ensure, clear, check, clear */
+	asb_package_clear (pkg, ASB_PACKAGE_ENSURE_DEPS);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 0);
+	ret = asb_package_ensure (pkg, ASB_PACKAGE_ENSURE_DEPS, &error);
+	g_assert_no_error (error);
+	g_assert (ret);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 3);
+	ret = asb_package_ensure (pkg, ASB_PACKAGE_ENSURE_DEPS, &error);
+	g_assert_no_error (error);
+	g_assert (ret);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 3);
+	asb_package_clear (pkg, ASB_PACKAGE_ENSURE_DEPS);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 3);
+	asb_package_clear (pkg, ASB_PACKAGE_ENSURE_DEPS);
+	g_assert_cmpint (asb_package_get_deps(pkg)->len, ==, 0);
+
 	/* compare */
 	g_assert_cmpint (asb_package_compare (pkg, pkg), ==, 0);