linux autotools 软件包管理

linux autotools 软件包管理  ------by free coffee

从GNU网站上抄下来的，作了些备注。以备查用，也方便大家。
原文请看

2.4.1 Creating amhello-1.0.tar.gz

做一个简单的发布包。

Here is how we can recreate amhello-1.0.tar.gz from scratch. The package is simple enough so that we will only need to write 5 files. (You may copy them from the final amhello-1.0.tar.gz that is distributed with Automake if you do not want to write them.)

Create the following files in an empty directory.

进工作目录：cd ~/workspace。建src子目录文件夹放原代码main.c

• src/main.c is the source file for the hello program. We store it in the src/ subdirectory, because later, when the package evolves, it will ease the addition of a man/ directory for man pages, a data/ directory for data files, etc.

            ~/amhello % cat src/main.c
            #include 
            #include 
            
            int
            main (void)
            {
              puts ("Hello World!");
              puts ("This is " PACKAGE_STRING "."); //会输出版本信息
              return 0;
            }

• 做文档README,这个文件默认安装时会放在/usr/local/share/doc/hello下面
  
• README contains some very limited documentation for our little package.

            ~/amhello % cat README
            This is a demonstration package for GNU Automake.
            Type `info Automake' to read the Automake manual.
  

• Makefile.am and src/Makefile.am contain Automake instructions for these two directories.  顶目录和子目录都要Makfefile.am，以供autoconf(生成configure.ac)和automake(生成多个Makefile.in）调用。

            ~/amhello % cat src/Makefile.am
            bin_PROGRAMS = hello
            hello_SOURCES = main.c
            ~/amhello % cat Makefile.am
            SUBDIRS = src
            dist_doc_DATA = README 
  

 这里本来还有个AUTOMAKE_OPTIONS选项：AUTOMAKE_OPTIONS=foreign..

automake提供了3种软件等级：foreign、gnu、gnits，让用户选择使用，默认等级是gnu,这个等级比较严格必须包含几个特定文件，如GPL协议。现在使用的foreign只是检测必要的文件。

bin_PROGRAMS＝file定义了要产生的执行文件名。如果产生多个可执行文件，每个文件名用空格隔开。file_SOURCES定义file这个执行程序的依赖文件。同样的，对于多个执行文件，那就要定义相应的file_SOURCES。

• Finally, configure.ac contains Autoconf instructions to create the configure script.

            ~/amhello % cat configure.ac
            AC_INIT([amhello], [1.0], [[e-mail]]) //版本
            AM_INIT_AUTOMAKE([-Wall -Werror foreign])  //定makefile开关
            AC_PROG_CC             //使configure脚本在系统中查找编译器，并确定CC
            AC_CONFIG_HEADERS([config.h]) //查找定义在configure.ac里的#define并生成configure.h
            AC_CONFIG_FILES([          //确定要生成哪些Makefile
             Makefile
             src/Makefile
            ])
            AC_OUTPUT
  

• 
  
• 
  

Once you have these five files, it is time to run the Autotools to instantiate the build system. Do this using the autoreconf command as follows:

     ~/amhello % autoreconf --install
     configure.ac: installing `./install-sh'
     configure.ac: installing `./missing'
     src/Makefile.am: installing `./depcomp'

At this point the build system is complete.

In addition to the three scripts mentioned in its output, you can see that autoreconf created four other files: configure, config.h.in, Makefile.in, and src/Makefile.in. The latter three files are templates that will be adapted to the system by configure under the names config.h, Makefile, and src/Makefile. Let's do this:

     ~/amhello % ./configure
     checking for a BSD-compatible install... /usr/bin/install -c
     checking whether build environment is sane... yes
     checking for gawk... no
     checking for mawk... mawk
     checking whether make sets $(MAKE)... yes
     checking for gcc... gcc
     checking for C compiler default output file name... a.out
     checking whether the C compiler works... yes
     checking whether we are cross compiling... no
     checking for suffix of executables...
     checking for suffix of object files... o
     checking whether we are using the GNU C compiler... yes
     checking whether gcc accepts -g... yes
     checking for gcc option to accept ISO C89... none needed
     checking for style of include used by make... GNU
     checking dependency style of gcc... gcc3
     configure: creating ./config.status
     config.status: creating Makefile
     config.status: creating src/Makefile
     config.status: creating config.h
     config.status: executing depfiles commands

You can see Makefile, src/Makefile, and config.h being created at the end after configure has probed the system. It is now possible to run all the targets we wish (see ). For instance:

     ~/amhello % make
     ...
     ~/amhello % src/hello
     Hello World!
     This is amhello 1.0.
     ~/amhello % make distcheck
     ...
     =============================================
     amhello-1.0 archives ready for distribution:
     amhello-1.0.tar.gz
     =============================================

这样就生成了amhello-1.0.tar.gz.解压开来就可以./configure --prefix=..... 
make
sudo make install
了。
总结：
autotools主要的工具是autoconf,和automake。若只用这两工具的话configure.ac要自己写，如果项目大了，很麻烦。可以用autoscan扫描项目，生成configure.scan稍加修改就可以成configure.am，
至于Makefile.am 就只有自己写了。有很多文章介绍怎么一步步用aclocal autoconf，个人觉得比较麻烦
，可用autoreconf --install省去麻烦。