open_path() is a central function in all API calls to FSFS repos, so it can always use a bit of tuning.  This time, we replace the O(N^2) usage of svn_fspath__join() with a linear stringbuf traversal.
open_path() is a central function in all API calls to FSFS repos, so it
can always use a bit of tuning.  This time, we replace the O(N^2) usage
of svn_fspath__join() with a linear stringbuf traversal.

* subversion/libsvn_fs_fs/tree.c
  (open_path): copy path to a stringbuf and simply shift the terminator
               position while iterating over the path instead of copying
               it at every iteration.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1483301 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion