Detect ext4 based on their superblock magic

src/pu-emmc.c

@@ -379,13 +379,17 @@ pu_emmc_write_data(PuFlash *flash,
                     return FALSE;
                 if (!pu_umount(part_mount, error))
                     return FALSE;
-            } else if (g_regex_match_simple(".ext[234]$", path, 0, 0)) {
+            } else if (g_regex_match_simple(".ext[234]$", path, 0, 0) ||
+                       pu_is_ext234_image(path)) {
                 if (!pu_write_raw(path, part_path, self->device, 0, 0, 0, error))
                     return FALSE;
                 if (!pu_resize_filesystem(part_path, error))
                     return FALSE;
                 if (!pu_set_ext_label(part_path, part->label, error))
                     return FALSE;
+            } else if (!part->filesystem) {
+                if (!pu_write_raw(path, part_path, self->device, 0, 0, 0, error))
+                    return FALSE;
             } else {
                 if (!pu_mount(part_path, part_mount, NULL, NULL, error))
                     return FALSE;

src/pu-mount.c

@@ -92,6 +92,7 @@ pu_mount(const gchar *source,
          GError **error)
 {
     gint ret;
+    gint status;
     struct libmnt_context *ctx;
 
     g_return_val_if_fail(g_strcmp0(source, "") > 0, FALSE);
@@ -116,9 +117,11 @@ pu_mount(const gchar *source,
         mnt_context_append_options(ctx, options);
 
     ret = mnt_context_mount(ctx);
-    if (ret || mnt_context_get_status(ctx) != 1) {
+    status = mnt_context_get_status(ctx);
+    if (ret || status != 1) {
         g_set_error(error, PU_ERROR, PU_ERROR_MOUNT,
-                    "Failed mounting '%s' to '%s'", source, mount_point);
+                    "Failed mounting '%s' to '%s': ret %d, status %d",
+                    source, mount_point, ret, status);
         mnt_free_context(ctx);
         return FALSE;
     }
@@ -132,6 +135,7 @@ pu_umount(const gchar *mount_point,
           GError **error)
 {
     gint ret;
+    gint status;
     struct libmnt_context *ctx;
 
     g_return_val_if_fail(g_strcmp0(mount_point, "") > 0, FALSE);
@@ -148,9 +152,11 @@ pu_umount(const gchar *mount_point,
     }
     mnt_context_set_target(ctx, mount_point);
     ret = mnt_context_umount(ctx);
-    if (ret || mnt_context_get_status(ctx) != 1) {
+    status = mnt_context_get_status(ctx);
+    if (ret || status != 1) {
         g_set_error(error, PU_ERROR, PU_ERROR_MOUNT,
-                    "Failed unmounting '%s'", mount_point);
+                    "Failed unmounting '%s': ret %d, status %d",
+                    mount_point, ret, status);
         mnt_free_context(ctx);
         return FALSE;
     }

src/pu-utils.c

@@ -408,6 +408,33 @@ pu_is_drive(const gchar *device)
     return ret;
 }
 
+gboolean
+pu_is_ext234_image(const gchar *path)
+{
+    blkid_probe pr;
+    const gchar *type = NULL;
+    gboolean ret = FALSE;
+
+    g_return_val_if_fail(g_strcmp0(path, "") > 0, FALSE);
+
+    pr = blkid_new_probe_from_filename(path);
+    if (!pr) {
+        return ret;
+    }
+
+    blkid_probe_enable_superblocks(pr, 1);
+    blkid_probe_set_superblocks_flags(pr, BLKID_SUBLKS_TYPE);
+
+    if (blkid_do_safeprobe(pr) == 0) {
+        if (blkid_probe_lookup_value(pr, "TYPE", &type, NULL) == 0) {
+            ret = (type && g_regex_match_simple("^ext[234]$", type, 0, 0));
+        }
+    }
+
+    blkid_free_probe(pr);
+    return ret;
+}
+
 gboolean
 pu_wait_for_partitions(GError **error)
 {

src/pu-utils.h

@@ -47,6 +47,7 @@ gboolean pu_partition_set_partuuid(const gchar *device,
                                    const gchar *partuuid,
                                    GError **error);
 gboolean pu_is_drive(const gchar *device);
+gboolean pu_is_ext234_image(const gchar *path);
 gboolean pu_wait_for_partitions(GError **error);
 gboolean pu_set_hwreset(const gchar *device,
                         const gchar *hwreset,

tests/utils.c

@@ -194,6 +194,17 @@ test_device_get_partition_pattern(void)
     g_assert_false(g_regex_match_simple(pattern, "/dev/sdb1", 0, 0));
 }
 
+static void
+test_is_ext234_image(void)
+{
+    g_assert_true(pu_is_ext234_image("data/root.ext4"));
+    g_assert_false(pu_is_ext234_image("data/random.bin"));
+    g_assert_false(pu_is_ext234_image("data/file-zero.txt"));
+    g_assert_false(pu_is_ext234_image("data/file-integer.txt"));
+    g_assert_false(pu_is_ext234_image("data/lorem.tar"));
+    g_assert_false(pu_is_ext234_image("data/lorem.txt"));
+}
+
 int
 main(int argc,
      char *argv[])
@@ -223,6 +234,7 @@ main(int argc,
                     test_device_get_partition_path_fail);
     g_test_add_func("/utils/str_pre_remove", test_str_pre_remove);
     g_test_add_func("/utils/device_get_partition_pattern", test_device_get_partition_pattern);
+    g_test_add_func("/utils/is_ext234_image", test_is_ext234_image);
 
     return g_test_run();
 }