inode.c: do not create blob from zero-sized data buffer

Moving forwards towards eliminating zero-size blobs: make
inode_add_stream_with_data() and inode_replace_stream_data() use a NULL
blob pointer for zero-length buffers.  Currently this can happen if a
Windows reparse point has no reparse data or if an empty named data
stream is created in a mounted WIM image.

diff --git a/src/inode.c b/src/inode.c
index 6277f0c427d678e49959240963921a898e160ec3..16ae0d229915eb9a6fe65505cfda35a1a67bb5ee 100644 (file)
--- a/src/inode.c
+++ b/src/inode.c
@@ -342,11 +342,13 @@ inode_replace_stream_data(struct wim_inode *inode,
                          const void *data, size_t size,
                          struct blob_table *blob_table)
 {
                          const void *data, size_t size,
                          struct blob_table *blob_table)
 {

-       struct blob_descriptor *new_blob;
+       struct blob_descriptor *new_blob = NULL;

 
 

-       new_blob = new_blob_from_data_buffer(data, size, blob_table);
-       if (!new_blob)
-               return false;
+       if (size) {
+               new_blob = new_blob_from_data_buffer(data, size, blob_table);
+               if (!new_blob)
+                       return false;
+       }

 
        inode_replace_stream_blob(inode, strm, new_blob, blob_table);
        return true;
 
        inode_replace_stream_blob(inode, strm, new_blob, blob_table);
        return true;


@@ -378,16 +380,18 @@ inode_add_stream_with_data(struct wim_inode *inode,
                           struct blob_table *blob_table)
 {
        struct wim_inode_stream *strm;
                           struct blob_table *blob_table)
 {
        struct wim_inode_stream *strm;

-       struct blob_descriptor *blob;
+       struct blob_descriptor *blob = NULL;

 
        strm = inode_add_stream(inode, stream_type, stream_name, NULL);
        if (!strm)
                return false;
 
 
        strm = inode_add_stream(inode, stream_type, stream_name, NULL);
        if (!strm)
                return false;
 

-       blob = new_blob_from_data_buffer(data, size, blob_table);
-       if (!blob) {
-               inode_remove_stream(inode, strm, blob_table);
-               return false;
+       if (size) {
+               blob = new_blob_from_data_buffer(data, size, blob_table);
+               if (unlikely(!blob)) {
+                       inode_remove_stream(inode, strm, blob_table);
+                       return false;
+               }

        }
 
        inode_set_stream_blob(inode, strm, blob);
        }
 
        inode_set_stream_blob(inode, strm, blob);