am 0032ce80: Fix back_up_files() error detection when opening/CRCing the file

Merge commit '0032ce80ac127e6bfb25d727162eee4af208dc77'

* commit '0032ce80ac127e6bfb25d727162eee4af208dc77':
  Fix back_up_files() error detection when opening/CRCing the file
diff --git a/libs/utils/BackupHelpers.cpp b/libs/utils/BackupHelpers.cpp
index e8e6c45..7f423a8 100644
--- a/libs/utils/BackupHelpers.cpp
+++ b/libs/utils/BackupHelpers.cpp
@@ -350,10 +350,11 @@
             FileState& g = newSnapshot.editValueAt(m);
 
             int fd = open(realFilename.string(), O_RDONLY);
-            if (fd != -1) {
+            if (fd < 0) {
                 // We can't open the file.  Don't report it as a delete either.  Let the
                 // server keep the old version.  Maybe they'll be able to deal with it
                 // on restore.
+                LOGP("Unable to open file %s - skipping", realFilename.string());
             } else {
                 g.crc32 = compute_crc32(fd);