我在涉及使用解析的项目中使用以下方法bison
:
我有一个文件m4/AC_PROG_BISON.m4
,它要么附加(automake 版本 1.11 或更低版本)或不附加(版本 1.12+)以下行到config.h文件:
/* Use *.h extension for parser header file */
#define BISON_USE_PARSER_H_EXTENSION 1
在需要包含解析器生成的标头的文件中,我添加了以下#ifdef 语句:
#include "config.h"
#if defined(BISON_USE_PARSER_H_EXTENSION)
# include "my_parser.h"
#else
# include "my_parser.hh"
#endif
另外去把事情做好我将以下行附加到configure.ac
AC_PROG_BISON
现在根据 automake 版本,将包含相关的标题。
文件内容:m4/AC_PROG_BISON.m4
dnl
dnl Check for bison
dnl AC_PROG_BISON([MIN_VERSION=2.0])
dnl
AC_DEFUN([AC_PROG_BISON], [
if test "x$1" = "x" ; then
bison_required_version="2.6"
else
bison_required_version="$1"
fi
AC_CHECK_PROG(have_prog_bison, [bison], [yes],[no])
AC_DEFINE_UNQUOTED([BISON_VERSION], [0.0],
[Defines bison version if bison is not present])
#Do not use *.h extension for parser header file but *.hh
bison_use_parser_h_extension=false
if test "$have_prog_bison" = "yes" ; then
AC_MSG_CHECKING([for bison version >= $bison_required_version])
bison_version=`bison --version | head -n 1 | cut '-d ' -f 4`
AC_DEFINE_UNQUOTED([BISON_VERSION], [$bison_version],
[Defines bison version])
if test "$bison_version" \< "$bison_required_version" ; then
BISON=:
AC_MSG_RESULT([no])
AC_MSG_ERROR([Bison version 2.6 or higher must be installed on the system!])
else
AC_MSG_RESULT([yes])
BISON=bison
AC_SUBST(BISON)
#Verify automake version
#Upto version 1.11 parser headers for yy files are with h extension, from 1.12 it is hh
automake_version=`automake --version | head -n 1 | cut '-d ' -f 4`
AC_DEFINE_UNQUOTED([AUTOMAKE_VERSION], [$automake_version],
[Defines automake version])
if test "$automake_version" \< "1.12" ; then
#Use *.h extension for parser header file
bison_use_parser_h_extension=true
echo "Automake version < 1.12"
AC_DEFINE([BISON_USE_PARSER_H_EXTENSION], [1],
[Use *.h extension for parser header file])
fi
fi
else
BISON=:
AC_MSG_RESULT([NO])
fi
AM_CONDITIONAL([BISON_USE_PARSER_H_EXTENSION], [test x$bison_use_parser_h_extension = xtrue])
AC_SUBST(BISON)
])