acinclude.m4

dnl Autoconf macros used by PINENTRY
dnl
dnl Copyright (C) 2002 g10 Code GmbH
dnl
dnl
dnl GNUPG_CHECK_TYPEDEF(TYPE, HAVE_NAME)
dnl Check whether a typedef exists and create a #define $2 if it exists
dnl
AC_DEFUN([GNUPG_CHECK_TYPEDEF],
  [ AC_MSG_CHECKING(for $1 typedef)
    AC_CACHE_VAL(gnupg_cv_typedef_$1,
    [AC_TRY_COMPILE([#define _GNU_SOURCE 1
    #include <stdlib.h>
    #include <sys/types.h>], [
    #undef $1
    int a = sizeof($1);
    ], gnupg_cv_typedef_$1=yes, gnupg_cv_typedef_$1=no )])
    AC_MSG_RESULT($gnupg_cv_typedef_$1)
    if test "$gnupg_cv_typedef_$1" = yes; then
        AC_DEFINE($2,1,[Defined if a `]$1[' is typedef'd])
    fi
  ])


######################################################################
# Check whether mlock is broken (hpux 10.20 raises a SIGBUS if mlock
# is not called from uid 0 (not tested whether uid 0 works)
# For DECs Tru64 we have also to check whether mlock is in librt
# mlock is there a macro using memlk()
######################################################################
dnl GNUPG_CHECK_MLOCK
dnl
define([GNUPG_CHECK_MLOCK],
  [ AC_CHECK_FUNCS(mlock)
    if test "$ac_cv_func_mlock" = "no"; then
        AC_CHECK_HEADERS(sys/mman.h)
        if test "$ac_cv_header_sys_mman_h" = "yes"; then
            # Add librt to LIBS:
            AC_CHECK_LIB(rt, memlk)
            AC_CACHE_CHECK([whether mlock is in sys/mman.h],
                            gnupg_cv_mlock_is_in_sys_mman,
                [AC_TRY_LINK([
                    #include <assert.h>
                    #ifdef HAVE_SYS_MMAN_H
                    #include <sys/mman.h>
                    #endif
                ], [
                    int i;

                    /* glibc defines this for functions which it implements
                     * to always fail with ENOSYS.  Some functions are actually
                     * named something starting with __ and the normal name
                     * is an alias.  */
                    #if defined (__stub_mlock) || defined (__stub___mlock)
                    choke me
                    #else
                    mlock(&i, 4);
                    #endif
                    ; return 0;
                ],
                gnupg_cv_mlock_is_in_sys_mman=yes,
                gnupg_cv_mlock_is_in_sys_mman=no)])
            if test "$gnupg_cv_mlock_is_in_sys_mman" = "yes"; then
                AC_DEFINE(HAVE_MLOCK,1,
                          [Defined if the system supports an mlock() call])
            fi
        fi
    fi
    if test "$ac_cv_func_mlock" = "yes"; then
        AC_MSG_CHECKING(whether mlock is broken)
          AC_CACHE_VAL(gnupg_cv_have_broken_mlock,
             AC_TRY_RUN([
                #include <stdlib.h>
                #include <unistd.h>
                #include <errno.h>
                #include <sys/mman.h>
                #include <sys/types.h>
                #include <fcntl.h>

                int main()
                {
                    char *pool;
                    int err;
                    long int pgsize = getpagesize();

                    pool = malloc( 4096 + pgsize );
                    if( !pool )
                        return 2;
                    pool += (pgsize - ((long int)pool % pgsize));

                    err = mlock( pool, 4096 );
                    if( !err || errno == EPERM )
                        return 0; /* okay */

                    return 1;  /* hmmm */
                }

            ],
            gnupg_cv_have_broken_mlock="no",
            gnupg_cv_have_broken_mlock="yes",
            gnupg_cv_have_broken_mlock="assume-no"
           )
         )
         if test "$gnupg_cv_have_broken_mlock" = "yes"; then
             AC_DEFINE(HAVE_BROKEN_MLOCK,1,
                       [Defined if the mlock() call does not work])
             AC_MSG_RESULT(yes)
             AC_CHECK_FUNCS(plock)
         else
            if test "$gnupg_cv_have_broken_mlock" = "no"; then
                AC_MSG_RESULT(no)
            else
                AC_MSG_RESULT(assuming no)
            fi
         fi
    fi
  ])