[gcab] trivial: Split up the code creating a GInputStream for a GCabFile

[Richard Hughes <rhughes src gnome org>]

commit c15a22781ef74cb226b7d09055015742ec96f5c4
Author: Richard Hughes <richard hughsie com>
Date:   Fri Dec 15 10:33:43 2017 +0000

    trivial: Split up the code creating a GInputStream for a GCabFile

 libgcab/gcab-cabinet.c |    9 +--------
 libgcab/gcab-file.c    |   13 +++++++++++++
 libgcab/gcab-priv.h    |    3 +++
 3 files changed, 17 insertions(+), 8 deletions(-)
---
diff --git a/libgcab/gcab-cabinet.c b/libgcab/gcab-cabinet.c
index e4cea35..f86c5bb 100644
--- a/libgcab/gcab-cabinet.c
+++ b/libgcab/gcab-cabinet.c
@@ -295,14 +295,7 @@ gcab_cabinet_write (GCabCabinet *self,
         if (file_callback)
             file_callback (file, user_data);
 
-        GFile *gfile = gcab_file_get_gfile (file);
-        if (gfile == NULL) {
-            g_set_error (error, GCAB_ERROR, GCAB_ERROR_FORMAT,
-                         "No GFile for %s", gcab_file_get_name (file));
-            return FALSE;
-        }
-
-        in = G_INPUT_STREAM (g_file_read (gfile, cancellable, error));
+        in = gcab_file_get_input_stream (file, cancellable, error);
         if (in == NULL)
             return FALSE;
 
diff --git a/libgcab/gcab-file.c b/libgcab/gcab-file.c
index 6ea46f2..ee8adb4 100644
--- a/libgcab/gcab-file.c
+++ b/libgcab/gcab-file.c
@@ -376,6 +376,19 @@ gcab_file_new_steal_cfile (cfile_t **cfile)
     return file;
 }
 
+G_GNUC_INTERNAL GInputStream *
+gcab_file_get_input_stream (GCabFile *self, GCancellable *cancellable, GError **error)
+{
+    /* backed by a GFile */
+    if (self->file != NULL)
+        return G_INPUT_STREAM (g_file_read (self->file, cancellable, error));
+
+    /* nothing to do */
+    g_set_error (error, GCAB_ERROR, GCAB_ERROR_FORMAT,
+                 "No GFile for %s", gcab_file_get_name (self));
+    return NULL;
+}
+
 /**
  * gcab_file_get_extract_name:
  * @file: a #GCabFile
diff --git a/libgcab/gcab-priv.h b/libgcab/gcab-priv.h
index 4d930ed..a4efab6 100644
--- a/libgcab/gcab-priv.h
+++ b/libgcab/gcab-priv.h
@@ -61,5 +61,8 @@ gboolean         gcab_folder_extract                 (GCabFolder *self,
                                                       gpointer callback_data,
                                                       GCancellable *cancellable,
                                                       GError **error);
+GInputStream    *gcab_file_get_input_stream          (GCabFile *file,
+                                                      GCancellable *cancellable,
+                                                      GError **error);
 
 #endif /* GCAB_PRIV_H */