autotool的使用

最近做的项目要用autotools，所以看了下：

《Autotools: a practitioner's guideto Autoconf, Automake and Libtool》

其实autotool用的很简单，这里介绍一种非lib的使用方法（lib的使用放到以后）：

 autoreconf -i --force
 ./configure
 make

比如在一个openssl项目里，下面是一个实例：

 root@test:~/sslclient# ls -lp
 總計 28
 drwxr-xr-x 2 root root 4096 2012-08-24 16:39 bin/
 drwxr-xr-x 2 root root 4096 2012-08-24 12:01 cacerts/
 drwxr-xr-x 2 root root 4096 2012-08-24 12:02 certs/
 drwxr-xr-x 2 root root 4096 2012-08-24 12:02 private/
 drwxr-xr-x 2 root root 4096 2012-08-24 17:11 src/

在src文件夹存放客户端和服务器端的实现，它们都依赖于ssl，encrypto两个动态库

 root@test:~/sslclient# ls -lp src
 總計 36
 -rw-r--r-- 1 root root  7963 2012-08-21 15:44 sample_cli.c
 -rw-r--r-- 1 root root  7884 2012-08-21 15:43 sample_srv.c

bin： 目录用于存放可执行文件

cacerts： 存放证书发行机构的证书

certs： 存放客户端和服务器证书

private： 存放秘钥

首先在工程的根目录添加configure.ac文件，这个文件可从autoscan中生成的configure.scan修改

 root@test:~/sslclient# cat configure.ac
 #                                               -*- Autoconf -*-
 # Process this file with autoconf to produce a configure script.


 AC_PREREQ([2.67])                          ＃autoconf的版本
 AC_INIT([ssl_sample], [0.0.1], [[email protected]])
 #[ssl_sample]:项目名称
 #[0.0.1]:版本号
 #[[email protected]]:开发者的联系方式
 AM_INIT_AUTOMAKE
 #初始化automake
 AC_CONFIG_SRCDIR([src/sample_srv.c])
 #在项目文件夹的随便一个文件
 AC_CONFIG_HEADERS([config.h])
 # 这个宏的意思是，从将模板里的@***@变量替换掉生成config.h头文件。模板是什么？默认是*.in文件，比如Makefile.in，这里就是config.h.in

 # Checks for programs.
 AC_PROG_CC


 # Checks for libraries.
 AC_SEARCH_LIBS([SSL_new], [ssl])
 # 调用SSL_new来测试，是否存在ssl库
 AC_SEARCH_LIBS([X509_NAME_oneline], [crypto])
 # 调用X509_NAME_oneline来测试，是否存在crypto库

 # Checks for header files.
 AC_CHECK_HEADERS([arpa/inet.h netdb.h netinet/in.h stdlib.h string.h sys/socket.h unistd.h])


 AC_CONFIG_FILES([Makefile
                  src/Makefile])
 # AC_CONFIG_FILES(file……, [command])
 # ‘file’ 参数指要创建的文件，该文件复制于一份输入文件（默认为‘file.in’），并替换掉输出变量值。‘file’就是一份输出文件，称之为系统编译环境配 置文件更准确一些。譬如，若‘FOO’是一个输出变量，而它的值为‘Bar’，那么在文件‘file.in’中出现的所有‘@FOO@’，在输出文件中都 会被替换为‘Bar’

 AC_OUTPUT
 # 用于完成所有输出

2.在工程的根目录添加Makefile.am,为Makefile.in的模板

 root@test:~/sslclient# cat Makefile.am
 SUBDIRS = src
 ＃指定源代码的目录

3.在源代码目录添加Makefile.am

 root@test:~/sslclient# cat src/Makefile.am
 bin_PROGRAMS = samplesrv samplecli
 #指定要输出的二进制文件
 samplesrv_SOURCES = sample_srv.c
 samplecli_SOURCES = sample_cli.c
 #指定二进制文件对应的C代码

好了，必须的配置文件都写好了，就可以跑了：

 root@test:~/sslclient# autoreconf -i
 configure.ac:6: installing `./install-sh'
 configure.ac:6: installing `./missing'
 src/Makefile.am: installing `./depcomp'
 Makefile.am: installing `./INSTALL'
 Makefile.am: required file `./NEWS' not found
 Makefile.am: required file `./README' not found
 Makefile.am: required file `./AUTHORS' not found
 Makefile.am: required file `./ChangeLog' not found
 Makefile.am: installing `./COPYING' using GNU General Public License v3 file
 Makefile.am:     Consider adding the COPYING file to the version control system
 Makefile.am:     for your code, to avoid questions about which license your project uses.
 autoreconf: automake failed with exit status: 1

首先man一下，看autoreconf用到的两个参数

 -i, --install
               copy missing auxiliary files

虽然指定了－i，拷贝所有的缺失文件，但

INSTALL  NEWS  README  AUTHORS  ChangeLog  COPYING必须手动加的。

 root@test:~/sslclient# touch INSTALL  NEWS  README  AUTHORS  ChangeLog  COPYING

 root@test:~/sslclient# autoreconf -i

 root@test:~/sslclient# ls -lp
 總計 356
 -rw-r--r-- 1 root root  34611 2012-08-25 03:55 aclocal.m4
 -rw-r--r-- 1 root root      0 2012-08-25 04:00 AUTHORS
 drwxr-xr-x 2 root root   4096 2012-08-25 03:55 autom4te.cache/
 drwxr-xr-x 2 root root   4096 2012-08-24 16:39 bin/
 drwxr-xr-x 2 root root   4096 2012-08-24 12:01 cacerts/
 drwxr-xr-x 2 root root   4096 2012-08-24 12:02 certs/
 -rw-r--r-- 1 root root      0 2012-08-25 04:00 ChangeLog
 -rw-r--r-- 1 root root   1777 2012-08-25 03:55 config.h.in
 -rwxr-xr-x 1 root root 162634 2012-08-25 03:55 configure
 -rw-r--r-- 1 root root    615 2012-08-24 16:13 configure.ac
 -rw-r--r-- 1 root root  35147 2012-08-25 04:00 COPYING
 -rwxr-xr-x 1 root root  18615 2012-08-25 03:55 depcomp
 -rw-r--r-- 1 root root  15578 2012-08-25 04:00 INSTALL
 -rwxr-xr-x 1 root root  13663 2012-08-25 03:55 install-sh
 -rw-r--r-- 1 root root     15 2012-08-24 15:35 Makefile.am
 -rw-r--r-- 1 root root  21430 2012-08-25 04:03 Makefile.in
 -rwxr-xr-x 1 root root  11419 2012-08-25 03:55 missing
 -rw-r--r-- 1 root root      0 2012-08-25 04:00 NEWS
 drwxr-xr-x 2 root root   4096 2012-08-24 12:02 private/
 -rw-r--r-- 1 root root      0 2012-08-25 04:00 README
 drwxr-xr-x 2 root root   4096 2012-08-25 03:55 src/

生成了大量熟悉的文件，基本都可以在开源项目中看到。

 root@test:~/sslclient# ./configure
 checking for a BSD-compatible install... /usr/bin/install -c
 checking whether build environment is sane... yes
 checking for a thread-safe mkdir -p... /bin/mkdir -p
 checking for gawk... no
 checking for mawk... mawk
 checking whether make sets $(MAKE)... yes
 checking for gcc... gcc
 checking whether the C compiler works... yes
 checking for C compiler default output file name... a.out
 checking for suffix of executables...
 checking whether we are cross compiling... no
 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
 checking for library containing SSL_new... -lssl<span style="white-space:pre">          </span>#我们在configure.ac中加入的AC_SEARCH_LIBS([SSL_new], [ssl])
 checking for library containing X509_NAME_oneline... none required<span style="white-space:pre">    </span>#这个是AC_SEARCH_LIBS([X509_NAME_oneline], [crypto])
 checking how to run the C preprocessor... gcc -E
 checking for grep that handles long lines and -e... /bin/grep
 checking for egrep... /bin/grep -E
 checking for ANSI C header files... yes
 checking for sys/types.h... yes
 checking for sys/stat.h... yes
 checking for stdlib.h... yes
 checking for string.h... yes
 checking for memory.h... yes
 checking for strings.h... yes
 checking for inttypes.h... yes
 checking for stdint.h... yes
 checking for unistd.h... yes
 checking arpa/inet.h usability... yes
 checking arpa/inet.h presence... yes
 checking for arpa/inet.h... yes
 checking netdb.h usability... yes
 checking netdb.h presence... yes
 checking for netdb.h... yes
 checking netinet/in.h usability... yes
 checking netinet/in.h presence... yes
 checking for netinet/in.h... yes
 checking for stdlib.h... (cached) yes
 checking for string.h... (cached) yes
 checking sys/socket.h usability... yes
 checking sys/socket.h presence... yes
 checking for sys/socket.h... yes
 checking for unistd.h... (cached) yes
 configure: creating ./config.status
 config.status: creating Makefile
 config.status: creating src/Makefile
 config.status: creating config.h
 config.status: executing depfiles commands

configure成功了，现在你可以看到在项目的根目录和src目录，都有Makefile.in,和Makefile生成了。

 root@test:~sslclient# make
 make all-recursivemake[1]: Entering directory `/home/sunbird/workplace/sslclient'Making all in srcmake[2]: Entering directory `/home/sunbird/workplace/sslclient/src'gcc -DHAVE_CONFIG_H -I. -I.. -g -O2 -MT sample_srv.o -MD -MP -MF .deps/sample_srv.Tpo -c -o sample_srv.o sample_srv.csample_srv.c: In function ‘main’:sample_srv.c:205:37: warning: passing argument 3 of ‘accept’ from incompatible pointer type/usr/include/sys/socket.h:214:12: note: expected ‘socklen_t * __restrict__’ but argument is of type ‘size_t *’sample_srv.c:210:2: warning: format ‘%lx’ expects type ‘long unsigned int’, but argument 2 has type ‘in_addr_t’mv -f .deps/sample_srv.Tpo .deps/sample_srv.Pogcc -g -O2 -o samplesrv sample_srv.o -lssl gcc -DHAVE_CONFIG_H -I. -I.. -g -O2 -MT sample_cli.o -MD -MP -MF .deps/sample_cli.Tpo -c -o sample_cli.o sample_cli.csample_cli.c: In function ‘main’:sample_cli.c:147:8: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_resultmv -f .deps/sample_cli.Tpo .deps/sample_cli.Pogcc -g -O2 -o samplecli sample_cli.o -lssl make[2]: Leaving directory `/home/sunbird/workplace/sslclient/src'make[2]: Entering directory `/home/sunbird/workplace/sslclient'make[2]: Leaving directory `/home/sunbird/workplace/sslclient'make[1]: Leaving directory `/home/sunbird/workplace/sslclient'

呵呵，寥寥数语就生成了那么多漂亮的Makefile语句，是不是很方便呢？