Re: Compiling on HP-UX 10.20 fails

Tom Lane wrote:
> Andrew Chernow <ac@esilo.com> writes:
>> I am trying to compile libpq on HP-UX 10.20 using gcc 2.95.3, cpu is a
>> 400MHz PA8500.  I'm using the 8.3.5 tarball.
>
> Yeah, 10.20 is a bit old and creaky, and the system headers are shy of a
> load in a few places.  I currently use the attached fixes.
>
>             regards, tom lane
>

That got rid of all warnings.  Although, it still fails to compile due
to gethostbyname_r:

thread.c:141: too many arguments to function `gethostbyname_r'

hpux 10.20, hpux 11 and aix (maybe more) use a 3 argument version, not 5:

int
gethostbyname_r(const char *name, struct hostent *result,
                 struct hostent_data *buffer);

I supplied a patch that includes a configure check.  NOTE: the hpux
platform check at the top of thread.c may not be cross-compiler, I think
they are from gcc.  Does the postgresql config system define platform
somewhere so I can #ifdef PG_HPUX?

--
Andrew Chernow
eSilo, LLC
every bit counts
http://www.esilo.com/
Index: configure.in
===================================================================
RCS file: /projects/cvsroot/pgsql/configure.in,v
retrieving revision 1.571
diff -C6 -r1.571 configure.in
*** configure.in    30 Oct 2008 12:28:51 -0000    1.571
--- configure.in    16 Nov 2008 05:15:59 -0000
***************
*** 1363,1374 ****
--- 1363,1392 ----
  if test "$PORTNAME" != "win32"; then
  AC_CHECK_HEADER(pthread.h, [], [AC_MSG_ERROR([pthread.h not found, required for --enable-thread-safety])])
  fi

  AC_CHECK_FUNCS([strerror_r getpwuid_r gethostbyname_r])

+ # determines if the system has a 3 or 5 argument gethostbyname_r, only needed with threads
+ # there is also a 6 arg version used by linux
+ if test "$enable_thread_safety" = yes ; then
+     AC_MSG_CHECKING([gethostbyname_r argument count])
+     AC_TRY_COMPILE(
+     [#undef _XOPEN_SOURCE_EXTENDED
+ #ifndef _REENTRANT
+ #define _REENTRANT
+ #endif
+ #ifndef _THREAD_SAFE
+ #define _THREAD_SAFE
+ #endif
+ #include <netdb.h>],
+     [gethostbyname_r((void *)0, (void *)0, (void *)0)],
+     [AC_DEFINE(GETHOSTBYNAME_R_ARGCNT, 3, [Define to the number of arguments gethostbyname_r accepts])
AC_MSG_RESULT(3)],
+     [AC_DEFINE(GETHOSTBYNAME_R_ARGCNT, 5, [Define to the number of arguments gethostbyname_r accepts])
AC_MSG_RESULT(5)])
+ fi
+
  # Do test here with the proper thread flags
  PGAC_FUNC_GETPWUID_R_5ARG
  PGAC_FUNC_STRERROR_R_INT

  CFLAGS="$_CFLAGS"
  LIBS="$_LIBS"
Index: src/port/thread.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/port/thread.c,v
retrieving revision 1.39
diff -C6 -r1.39 thread.c
*** src/port/thread.c    22 Apr 2008 13:06:57 -0000    1.39
--- src/port/thread.c    16 Nov 2008 05:16:00 -0000
***************
*** 9,20 ****
--- 9,27 ----
   *
   * $PostgreSQL: pgsql/src/port/thread.c,v 1.39 2008/04/22 13:06:57 mha Exp $
   *
   *-------------------------------------------------------------------------
   */

+ /* When _XOPEN_SOURCE_EXTENDED is defined, struct hostent_data does
+  * not get declared.  This structure is needed by hpux gethostbyname_r.
+  */
+ #if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY) && (defined(__hpux) || defined(__hpux__) || defined(hpux))
+ #undef _XOPEN_SOURCE_EXTENDED
+ #endif
+
  #include "c.h"

  #include <pwd.h>
  #if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY)
  #endif

***************
*** 126,142 ****
--- 133,171 ----
                  char *buffer, size_t buflen,
                  struct hostent ** result,
                  int *herrno)
  {
  #if defined(FRONTEND) && defined(ENABLE_THREAD_SAFETY) && defined(HAVE_GETHOSTBYNAME_R)

+ #if GETHOSTBYNAME_R_ARGCNT == 3
+     *result = NULL;
+
+     if (buflen < sizeof(struct hostent_data))
+     {
+         /* linux man page says this gets set when buffer is too small */
+         *herrno = ERANGE;
+         return -1;
+     }
+
+     if (gethostbyname_r(name, resultbuf, (struct hostent_data *)buffer))
+     {
+         *herrno = h_errno;
+         return -1;
+     }
+
+     *result = resultbuf;
+
+ /* 5 argument version.  There is also a 6 arg version found on linux. */
+ #else
      /*
       * broken (well early POSIX draft) gethostbyname_r() which returns 'struct
       * hostent *'
       */
      *result = gethostbyname_r(name, resultbuf, buffer, buflen, herrno);
+ #endif /* GETHOSTBYNAME_R_ARGCNT */
+
      return (*result == NULL) ? -1 : 0;
  #else

      /* no gethostbyname_r(), just use gethostbyname() */
      *result = gethostbyname(name);