wimlib_export_image(): improve duplicate image detection

[wimlib] / src / export_image.c

diff --git a/src/export_image.c b/src/export_image.c
index ff20a73f7f7f20b5e109196be854fb95abef9de5..da638322ee06c32d19217986653be498eea4e63d 100644 (file)
--- a/src/export_image.c
+++ b/src/export_image.c
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2012, 2013, 2014 Eric Biggers
+ * Copyright (C) 2012, 2013, 2014, 2015 Eric Biggers
  *
  * This file is free software; you can redistribute it and/or modify it under
  * the terms of the GNU Lesser General Public License as published by the Free
@@ -128,7 +128,7 @@ wimlib_export_image(WIMStruct *src_wim,
                             WIMLIB_EXPORT_FLAG_WIMBOOT))
                return WIMLIB_ERR_INVALID_PARAM;
 
-       if (!src_wim || !dest_wim || src_wim == dest_wim)
+       if (!src_wim || !dest_wim)
                return WIMLIB_ERR_INVALID_PARAM;
 
        if (!wim_has_metadata(src_wim) || !wim_has_metadata(dest_wim))
@@ -153,6 +153,21 @@ wimlib_export_image(WIMStruct *src_wim,
        }
        orig_dest_image_count = dest_wim->hdr.image_count;
 
+       /* We don't yet support having a single WIMStruct contain duplicate
+        * 'image_metadata' structures, so we must forbid this from happening.
+        * A duplication is possible if 'src_wim == dest_wim', if the same image
+        * is exported to the same destination WIMStruct multiple times, or if
+        * an image is exported in an A => B => A manner.  */
+       for (src_image = start_src_image;
+            src_image <= end_src_image; src_image++)
+       {
+               const struct wim_image_metadata *src_imd =
+                               src_wim->image_metadata[src_image - 1];
+               for (int i = 0; i < dest_wim->hdr.image_count; i++)
+                       if (dest_wim->image_metadata[i] == src_imd)
+                               return WIMLIB_ERR_DUPLICATE_EXPORTED_IMAGE;
+       }
+
        /* Blob checksums must be known before proceeding.  */
        ret = wim_checksum_unhashed_blobs(src_wim);
        if (ret)
@@ -249,10 +264,6 @@ wimlib_export_image(WIMStruct *src_wim,
                        dest_wim->hdr.boot_idx = dst_image;
        }
 
-       if (export_flags & WIMLIB_EXPORT_FLAG_GIFT) {
-               free_blob_table(src_wim->blob_table);
-               src_wim->blob_table = NULL;
-       }
        return 0;
 
 out_rollback: