Update comment for struct type's length field, introduce type_length_units

[deliverable/binutils-gdb.git] / gdb / ptrace.m4

dnl Copyright (C) 2012-2015 Free Software Foundation, Inc.
dnl
dnl This file is part of GDB.
dnl
dnl This program is free software; you can redistribute it and/or modify
dnl it under the terms of the GNU General Public License as published by
dnl the Free Software Foundation; either version 3 of the License, or
dnl (at your option) any later version.
dnl
dnl This program is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
dnl GNU General Public License for more details.
dnl
dnl You should have received a copy of the GNU General Public License
dnl along with this program.  If not, see <http://www.gnu.org/licenses/>.

dnl Check the return and argument types of ptrace.

AC_DEFUN([GDB_AC_PTRACE],
[

AC_CHECK_HEADERS([sys/ptrace.h ptrace.h])

# Needs to be tested in C++ mode, to detect whether we need to cast
# the first argument to enum __ptrace_request.
if test "$enable_build_with_cxx" = "yes"; then
    AC_LANG_PUSH([C++])
fi

gdb_ptrace_headers='
#include <sys/types.h>
#if HAVE_SYS_PTRACE_H
# include <sys/ptrace.h>
#endif
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
'
# There is no point in checking if we don't have a prototype.
AC_CHECK_DECLS(ptrace, [], [
  : ${gdb_cv_func_ptrace_ret='int'}
  : ${gdb_cv_func_ptrace_args='int,int,long,long'}
], $gdb_ptrace_headers)
# Check return type.  Varargs (used on GNU/Linux) conflict with the
# empty argument list, so check for that explicitly.
AC_CACHE_CHECK([return type of ptrace], gdb_cv_func_ptrace_ret,
  AC_TRY_COMPILE($gdb_ptrace_headers,
    [extern long ptrace (enum __ptrace_request, ...);],
    gdb_cv_func_ptrace_ret='long',
    AC_TRY_COMPILE($gdb_ptrace_headers,
      [extern int ptrace ();],
      gdb_cv_func_ptrace_ret='int',
      gdb_cv_func_ptrace_ret='long')))
AC_DEFINE_UNQUOTED(PTRACE_TYPE_RET, $gdb_cv_func_ptrace_ret,
  [Define as the return type of ptrace.])
# Check argument types.
AC_CACHE_CHECK([types of arguments for ptrace], gdb_cv_func_ptrace_args, [
  AC_TRY_COMPILE($gdb_ptrace_headers,
    [extern long ptrace (enum __ptrace_request, ...);],
    [gdb_cv_func_ptrace_args='enum __ptrace_request,int,long,long'],[
for gdb_arg1 in 'int' 'long'; do
 for gdb_arg2 in 'pid_t' 'int' 'long'; do
  for gdb_arg3 in 'int *' 'caddr_t' 'int' 'long' 'void *'; do
   for gdb_arg4 in 'int' 'long' 'void *'; do
     AC_TRY_COMPILE($gdb_ptrace_headers, [
extern $gdb_cv_func_ptrace_ret
  ptrace ($gdb_arg1, $gdb_arg2, $gdb_arg3, $gdb_arg4);
], [gdb_cv_func_ptrace_args="$gdb_arg1,$gdb_arg2,$gdb_arg3,$gdb_arg4";
    break 4;])
    for gdb_arg5 in 'int *' 'int' 'long'; do
     AC_TRY_COMPILE($gdb_ptrace_headers, [
extern $gdb_cv_func_ptrace_ret
  ptrace ($gdb_arg1, $gdb_arg2, $gdb_arg3, $gdb_arg4, $gdb_arg5);
], [
gdb_cv_func_ptrace_args="$gdb_arg1,$gdb_arg2,$gdb_arg3,$gdb_arg4,$gdb_arg5";
    break 5;])
    done
   done
  done
 done
done
# Provide a safe default value.
: ${gdb_cv_func_ptrace_args='int,int,long,long'}
])])
ac_save_IFS=$IFS; IFS=','
set dummy `echo "$gdb_cv_func_ptrace_args" | sed 's/\*/\*/g'`
IFS=$ac_save_IFS
shift
AC_DEFINE_UNQUOTED(PTRACE_TYPE_ARG1, $[1],
  [Define to the type of arg 1 for ptrace.])
AC_DEFINE_UNQUOTED(PTRACE_TYPE_ARG3, $[3],
  [Define to the type of arg 3 for ptrace.])
AC_DEFINE_UNQUOTED(PTRACE_TYPE_ARG4, $[4],
  [Define to the type of arg 4 for ptrace.])
if test -n "$[5]"; then
  AC_DEFINE_UNQUOTED(PTRACE_TYPE_ARG5, $[5],
    [Define to the type of arg 5 for ptrace.])
fi

if test "$enable_build_with_cxx" = "yes"; then
    AC_LANG_POP([C++])
fi
])