Imported from ../bash-2.05b.tar.gz.

lib/sh/rename.c

@@ -25,21 +25,52 @@
 #if !defined (HAVE_RENAME)
 
 #include <bashtypes.h>
+#include <posixstat.h>
 
 #if defined (HAVE_UNISTD_H)
 #  include <unistd.h>
 #endif
+#include <errno.h>
 
 #include <stdc.h>
 
+#ifndef errno
+extern int errno;
+#endif
+
 int
 rename (from, to)
      const char *from, *to;
 {
-  unlink (to);
+  struct stat fb, tb;
+
+  if (stat (from, &fb) < 0)
+    return -1;  
+
+  if (stat (to, &tb) < 0)
+    {
+      if (errno != ENOENT)
+	return -1;
+    }
+  else
+    {
+      if (fb.st_dev == tb.st_dev && fb.st_ino == tb.st_ino)
+        return 0;		/* same file */
+      if (unlink (to) < 0 && errno != ENOENT)
+        return -1;
+    }
+
   if (link (from, to) < 0)
     return (-1);
-  unlink (from);
+
+  if (unlink (from) < 0 && errno != ENOENT)
+    {
+      int e = errno;
+      unlink (to);
+      errno = e;
+      return (-1);
+    }
+
   return (0);
 }
 #endif /* !HAVE_RENAME */