Bug #600
closed
OFStandard::searchDirectoryRecursively() relies on undefined HAVE_READDIR_R
Added by Jörg Riesmeier about 11 years ago.
Updated over 5 years ago.
Description
OFStandard::searchDirectoryRecursively() checks HAVE_READDIR_R in order to determine whether to use readdir() or the thread-safe readdir_r(). However, HAVE_READDIR_R is never defined because it is neither checked by the GNU Autoconf nor the CMake configure mechanism.
What is defined and actually checked by the module "dcmwlm" is HAVE_OLD_READDIR_R (in combination with _REEENTRANT).
- Status changed from New to Closed
Closed by commit #a4a69b0167a08.
- % Done changed from 0 to 100
- Status changed from Closed to Reopened
- Target version changed from 3.6.2 to 3.6.6
- Operating System set to Linux
Apparently, the glibc version in which readdir_r was first marked as deprecated is 2.24. In earlier versions of glibc and on other libc implementations we have to assume that readdir() is thread unsafe, because Posix does not require it to be thread safe.
The presence of glibc can be determined by the __GLIBC__ macro being present (after inclusion e.g. of <stdio.h> or <stdlib.h>). The version number of glibc is available at compile time with the __GLIBC__ and __GLIBC_MINOR__ macros, which resolve to the major and minor version number. The following pseudocode could be used to avoid the deprecation warning on glibc systems:
#if defined(__GLIBC__) && (((__GLIBC__ == 2) && (__GLIBC_MINOR__ >= 24)) || (__GLIBC__ >= 3))
#defined READDIR_IS_THREADSAFE
#endif
#if defined(HAVE_READDIR_R) && !defined(READDIR_IS_THREADSAFE)
// use readdir_r()
#else
// use readdir()
#endif
In a few DCMTK modules, readdir()/readdir_r() are still used directly. These should be migrated to OFStandard::searchDirectoryRecursively() first, so that the system dependent code is only needed in one place. Affected are:
- private/dcmpps/libsrc/ppsmgram.cc
- public/dcmpstat/apps/dcmprscu.cc
- public/dcmwlm/libsrc/wlfsim.cc
Was already mentioned (see Note #3).
Fixed by commit #f421bce for public modules; commit #03a4f49 private modules.
- Status changed from Reopened to Closed
- Target version deleted (
3.6.6)
Also available in: Atom
PDF
Updated by Jan Schlamelcher 
Updated by 
Updated by 
Updated by