Cache the system temporary directory in Subversion, as apr never cached this for us even though it used to document that it did. (The documentation was fixed in the latest APR release.)
Cache the system temporary directory in Subversion, as apr never cached
this for us even though it used to document that it did.
(The documentation was fixed in the latest APR release.)

While locating the tempdirectory apr creates a temporary file, which it
deletes directly after creating. This reduces the number of IO operations
required for each temp file at the cost of an extra global pool.

* subversion/libsvn_subr/io.c
  (includes): Include private/svn_atomic.h
  (temp_dir_init_state, temp_dir): New static variables.
  (init_temp_dir): New function.
  (svn_io_temp_dir):
    Ensure and return the cached tempdirectory instead of
    searching and trying a tempdirectory again.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@878043 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion