Author: sebor
Date: Mon Jan 9 11:05:32 2006
New Revision: 367363
URL: http://svn.apache.org/viewcvs?rev=367363&view=rev
Log:
2006-01-09 Martin Sebor <[EMAIL PROTECTED]>
STDCXX-106
* memattr.cpp (__rw_memattr): Used getpagesize(3) instead of sysconf(3)
when neither _SC_PAGE_SIZE or _SC_PAGESIZE is #defined in <unistd.h>
(e.g., on BSD UNIX).
Restored errno to its original value if it got clobbered by one of the
called functions.
Modified:
incubator/stdcxx/trunk/src/memattr.cpp
Modified: incubator/stdcxx/trunk/src/memattr.cpp
URL:
http://svn.apache.org/viewcvs/incubator/stdcxx/trunk/src/memattr.cpp?rev=367363&r1=367362&r2=367363&view=diff
==============================================================================
--- incubator/stdcxx/trunk/src/memattr.cpp (original)
+++ incubator/stdcxx/trunk/src/memattr.cpp Mon Jan 9 11:05:32 2006
@@ -35,15 +35,21 @@
// working around SunOS bug #568
# include <time.h>
# endif
-# include <unistd.h> // for sysconf
-# include <sys/mman.h> // for mincore
+# include <unistd.h> // for getpagesize(), sysconf()
+# include <sys/mman.h> // for mincore()
# include <sys/types.h>
# ifndef _SC_PAGE_SIZE
- // fall back on the alternative
-# define _SC_PAGE_SIZE _SC_PAGESIZE
-# endif
-
+ // fall back on the alternative macro if it exists,
+ // or use getpagesize() otherwise
+# ifndef _SC_PAGESIZE
+# define GETPAGESIZE() getpagesize ()
+# else
+# define GETPAGESIZE() sysconf (_SC_PAGESIZE)
+# endif
+# else
+# define GETPAGESIZE() sysconf (_SC_PAGE_SIZE)
+# endif // _SC_PAGE_SIZE
#else
# include <windows.h> // for everything (ugh)
#endif // _WIN{32,64}
@@ -83,8 +89,10 @@
#if !defined (_WIN32) && !defined (_WIN64)
+ const int errno_save = errno;
+
// determine the system page size in bytes
- static const _RWSTD_SIZE_T pgsz = size_t (sysconf (_SC_PAGE_SIZE));
+ static const _RWSTD_SIZE_T pgsz = size_t (GETPAGESIZE ());
// compute the address of the beginning of the page
// to which the address `addr' belongs
@@ -108,16 +116,28 @@
// on Solaris use mincore() instead of madvise() since
// the latter is unreliable
- if (-1 == mincore (next, 1, &dummy) && ENOMEM == errno)
- return next == page ? -1 : DIST (next, addr);
+ if (-1 == mincore (next, 1, &dummy)) {
+
+ const int err = errno;
+ errno = errno_save;
+
+ if (ENOMEM == err)
+ return next == page ? -1 : DIST (next, addr);
+ }
# elif !defined (_RWSTD_NO_MADVISE)
// on HP-UX, Linux, use madvise() as opposed to mincore()
// since the latter fails for address ranges that aren't
// backed by a file (such as stack variables)
- if (-1 == madvise (next, 1, MADV_WILLNEED) && ENOMEM == errno)
- return next == page ? -1 : DIST (next, addr);
+ if (-1 == madvise (next, 1, MADV_WILLNEED)) {
+
+ const int err = errno;
+ errno = errno_save;
+
+ if (ENOMEM == err)
+ return next == page ? -1 : DIST (next, addr);
+ }
# endif
