dnl $Id$
dnl config.m4 for extension sync

PHP_ARG_ENABLE(sync, whether to enable synchronization object support (--enable-sync),
  [  --enable-sync           Enable synchronization object support])

if test "$PHP_SYNC" != "no"; then
  dnl # Check for shm_open() support.
  AC_MSG_CHECKING([for shm_open in -pthread -lrt])

  SAVED_LIBS="$LIBS"
  LIBS="$LIBS -pthread -lrt"

  AC_TRY_LINK([
    #include <fcntl.h>
    #include <sys/mman.h>
  ], [
    int fp = shm_open("", O_RDWR | O_CREAT | O_EXCL, 0666);
  ], [
    have_shm_open=yes
    AC_MSG_RESULT([yes])

    PHP_ADD_LIBRARY(rt,,SYNC_SHARED_LIBADD)
    PHP_SUBST(SYNC_SHARED_LIBADD)
  ], [
    AC_MSG_RESULT([no (attempting fallback)])

    dnl # Fallback attempt to link without -lrt.
    AC_MSG_CHECKING([for shm_open in -pthread])

    LIBS="$SAVED_LIBS -pthread"

    AC_TRY_LINK([
      #include <fcntl.h>
      #include <sys/mman.h>
    ], [
      int fp = shm_open("", O_RDWR | O_CREAT | O_EXCL, 0666);
    ], [
      have_shm_open=yes
      AC_MSG_RESULT([yes])
    ], [
      AC_MSG_ERROR([shm_open() is not available on this platform])
    ])
  ])

  dnl # Finish defining the basic extension support.
  AC_DEFINE(HAVE_SYNC, 1, [Whether you have synchronization object support])
  PHP_NEW_EXTENSION(sync, sync.c, $ext_shared)
fi