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<a name='TOP'><h2><a href='../mains.html'>root</a>/<a href='../files/110.html'>tools</a>/build.c</h2>
<i><font color='green'>/* [<][>]<a href='#L63'>[^]</a><a href='#L77'>[v]</a>[top]<a href='#BOTTOM'>[bottom]</a><a href='../mains.html'>[index]</a><a href='../help.html'>[help]</a> */</font></i>
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<h2>DEFINITIONS</h2>
This source file includes following definitions.
<ol>
<li><a href='#L63' title='Defined at 63.'>die</a>
<li><a href='#L71' title='Defined at 71.'>usage</a>
<li><a href='#L77' title='Defined at 77.'>main</a>
</ol>
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<pre>
<a name='L1'><i><font color='green'>/*</font></i>
<a name='L2'><i><font color='green'>* linux/tools/build.c</font></i>
<a name='L3'><i><font color='green'>*</font></i>
<a name='L4'><i><font color='green'>* (C) 1991 Linus Torvalds</font></i>
<a name='L5'><i><font color='green'>*/</font></i>
<a name='L6'>
<a name='L7'><i><font color='green'>/*</font></i>
<a name='L8'><i><font color='green'>* This file builds a disk-image from three different files:</font></i>
<a name='L9'><i><font color='green'>*</font></i>
<a name='L10'><i><font color='green'>* - bootsect: max 510 bytes of 8086 machine code, loads the rest</font></i>
<a name='L11'><i><font color='green'>* - setup: max 4 sectors of 8086 machine code, sets up system parm</font></i>
<a name='L12'><i><font color='green'>* - system: 80386 code for actual system</font></i>
<a name='L13'><i><font color='green'>*</font></i>
<a name='L14'><i><font color='green'>* It does some checking that all files are of the correct type, and</font></i>
<a name='L15'><i><font color='green'>* just writes the result to stdout, removing headers and padding to</font></i>
<a name='L16'><i><font color='green'>* the right amount. It also writes some system data to stderr.</font></i>
<a name='L17'><i><font color='green'>*/</font></i>
<a name='L18'><i><font color='green'>/*</font></i>
<a name='L19'><i><font color='green'>* 该程序从三个不同的程序中创建磁盘映象文件：</font></i>
<a name='L20'><i><font color='green'>*</font></i>
<a name='L21'><i><font color='green'>* - bootsect：该文件的8086 机器码最长为510 字节，用于加载其它程序。</font></i>
<a name='L22'><i><font color='green'>* - setup：该文件的8086 机器码最长为4 个磁盘扇区，用于设置系统参数。</font></i>
<a name='L23'><i><font color='green'>* - system：实际系统的80386 代码。</font></i>
<a name='L24'><i><font color='green'>*</font></i>
<a name='L25'><i><font color='green'>* 该程序首先检查所有程序模块的类型是否正确，并将检查结果在终端上显示出来，</font></i>
<a name='L26'><i><font color='green'>* 然后删除模块头部并扩充大正确的长度。该程序也会将一些系统数据写到stderr。</font></i>
<a name='L27'><i><font color='green'>*/</font></i>
<a name='L28'>
<a name='L29'><i><font color='green'>/*</font></i>
<a name='L30'><i><font color='green'>* Changes by tytso to allow root device specification</font></i>
<a name='L31'><i><font color='green'>*/</font></i>
<a name='L32'><i><font color='green'>/*</font></i>
<a name='L33'><i><font color='green'>* tytso 对该程序作了修改，以允许指定根文件设备。</font></i>
<a name='L34'><i><font color='green'>*/</font></i>
<a name='L35'>
<a name='L36'><font color='darkred'>#include</font> <stdio.h> <i><font color='green'>/* fprintf */</font></i> <i><font color='green'>/* 使用其中的fprintf() */</font></i>
<a name='L37'><font color='darkred'>#include</font> <<a href='42.html'>string.h</a>> <i><font color='green'>/* 字符串操作 */</font></i>
<a name='L38'><font color='darkred'>#include</font> <stdlib.h> <i><font color='green'>/* contains exit */</font></i> <i><font color='green'>/* 含有exit() */</font></i>
<a name='L39'><font color='darkred'>#include</font> <<a href='45.html'>sys/types.h</a>> <i><font color='green'>/* unistd.h needs this */</font></i> <i><font color='green'>/* 供unistd.h 使用 */</font></i>
<a name='L40'><font color='darkred'>#include</font> <<a href='43.html'>sys/stat.h</a>> <i><font color='green'>/* 文件状态信息结构 */</font></i>
<a name='L41'><font color='darkred'>#include</font> <<a href='31.html'>linux/fs.h</a>> <i><font color='green'>/* 文件系统 */</font></i>
<a name='L42'><font color='darkred'>#include</font> <<a href='50.html'>unistd.h</a>> <i><font color='green'>/* contains read/write */</font></i> <i><font color='green'>/* 含有read()/write() */</font></i>
<a name='L43'><font color='darkred'>#include</font> <<a href='29.html'>fcntl.h</a>> <i><font color='green'>/* 文件操作模式符号常数 */</font></i>
<a name='L44'>
<a name='L45'><font color='darkred'>#define</font> <a href='../R/130.html' title='Multiple refered from 4 places.'>MINIX_HEADER</a> 32 <i><font color='green'>// minix 二进制模块头部长度为32 字节。</font></i>
<a name='L46'><font color='darkred'>#define</font> <a href='../S/96.html#L225' title='Refered from 225 in tools/build.c.'>GCC_HEADER</a> 1024 <i><font color='green'>// GCC 头部信息长度为1024 字节。</font></i>
<a name='L47'>
<a name='L48'><font color='darkred'>#define</font> <a href='../S/96.html#L238' title='Refered from 238 in tools/build.c.'>SYS_SIZE</a> 0x2000 <i><font color='green'>// system 文件最长节数(字节数为SYS_SIZE*16=128KB)。</font></i>
<a name='L49'>
<a name='L50'>
<a name='L51'><font color='darkred'>#define</font> <a href='../S/96.html#L112' title='Refered from 112 in tools/build.c.'>DEFAULT_MAJOR_ROOT</a> 3 <i><font color='green'>// 默认根设备主设备号 - 3（硬盘）。</font></i>
<a name='L52'><font color='darkred'>#define</font> <a href='../S/96.html#L113' title='Refered from 113 in tools/build.c.'>DEFAULT_MINOR_ROOT</a> 6 <i><font color='green'>// 默认根设备次设备号 - 6（第2 个硬盘的第1 分区）。</font></i>
<a name='L53'>
<a name='L54'><i><font color='green'>/* max nr of sectors of setup: don't change unless you also change</font></i>
<a name='L55'><i><font color='green'>* bootsect etc */</font></i>
<a name='L56'><i><font color='green'>/* 下面指定setup 模块占的最大扇区数：不要改变该值，除非也改变bootsect 等相应文件。</font></i>
<a name='L57'><i><font color='green'>#define SETUP_SECTS 4 // setup 最大长度为4 个扇区（4*512 字节）。</font></i>
<a name='L58'><i><font color='green'>*/</font></i>
<a name='L59'><font color='darkred'>#define</font> <a href='../S/96.html#L202' title='Refered from 202 in tools/build.c.'>STRINGIFY</a>(x) #x <i><font color='green'>// 用于出错时显示语句中表示扇区数。</font></i>
<a name='L60'>
<a name='L61'><i><font color='green'>//// 显示出错信息，并终止程序。</font></i>
<a name='L62'><b>void</b>
<a name='L63'><a href='../R/433.html' title='Multiple refered from 45 places.'>die</a> (<b>char</b> *str)
<a name='L64'><font color='red'>{</font>
<a name='L65'> fprintf (stderr, "%s\n", <a href='../S/36.html#L267' title='Defined at 267 in include/linux/sched.h.'>str</a>);
<a name='L66'> exit (1);
<a name='L67'><font color='red'>}</font>
<a name='L68'>
<a name='L69'><i><font color='green'>// 显示程序使用方法，并退出。</font></i>
<a name='L70'><b>void</b>
<a name='L71'><a href='../S/96.html#L86' title='Refered from 86 in tools/build.c.'>usage</a> (<b>void</b>)
<a name='L72'><font color='red'>{</font>
<a name='L73'> <a href='../D/757.html' title='Multiple defined in 2 places.'>die</a> ("Usage: build bootsect setup system [rootdev] [> image]");
<a name='L74'><font color='red'>}</font>
<a name='L75'>
<a name='L76'><b>int</b>
<a name='L77'>main (<b>int</b> argc, <b>char</b> **argv)
<a name='L78'><font color='red'>{</font>
<a name='L79'> <b>int</b> <a href='../D/839.html' title='Multiple defined in 4 places.'>i</a>, c, id;
<a name='L80'> <b>char</b> <a href='../D/716.html' title='Multiple defined in 16 places.'>buf</a>[1024];
<a name='L81'> <b>char</b> major_root, minor_root;
<a name='L82'> <b>struct</b> stat sb;
<a name='L83'>
<a name='L84'><i><font color='green'>// 如果程序命令行参数不是4 或5 个，则显示程序用法并退出。</font></i>
<a name='L85'> <b>if</b> ((argc != 4) && (argc != 5))
<a name='L86'> <a href='../S/96.html#L71' title='Defined at 71 in tools/build.c.'>usage</a> ();
<a name='L87'><i><font color='green'>// 如果参数是5 个，则说明带有根设备名。</font></i>
<a name='L88'> <b>if</b> (argc == 5)
<a name='L89'> <font color='red'>{</font>
<a name='L90'><i><font color='green'>// 如果根设备名是软盘("FLOPPY")，则取该设备文件的状态信息，若出错则显示信息，退出。</font></i>
<a name='L91'> <b>if</b> (<a href='../S/42.html#L119' title='Defined at 119 in include/string.h.'>strcmp</a> (argv[4], "FLOPPY"))
<a name='L92'> <font color='red'>{</font>
<a name='L93'> <b>if</b> (stat (argv[4], &sb))
<a name='L94'> <font color='red'>{</font>
<a name='L95'> perror (argv[4]);
<a name='L96'> <a href='../D/757.html' title='Multiple defined in 2 places.'>die</a> ("Couldn't stat root device.");
<a name='L97'> <font color='red'>}</font>
<a name='L98'><i><font color='green'>// 若成功则取该设备名状态结构中的主设备号和次设备号。</font></i>
<a name='L99'> major_root = <a href='../S/31.html#L49' title='Defined at 49 in include/linux/fs.h.'>MAJOR</a> (sb.st_rdev);
<a name='L100'> minor_root = <a href='../D/238.html' title='Multiple defined in 2 places.'>MINOR</a> (sb.st_rdev);
<a name='L101'> <font color='red'>}</font>
<a name='L102'> <b>else</b>
<a name='L103'> <font color='red'>{</font>
<a name='L104'><i><font color='green'>// 否则让主设备号和次设备号取0。</font></i>
<a name='L105'> major_root = 0;
<a name='L106'> minor_root = 0;
<a name='L107'> <font color='red'>}</font>
<a name='L108'><i><font color='green'>// 若参数只有4 个，则让主设备号和次设备号等于系统默认的根设备。</font></i>
<a name='L109'> <font color='red'>}</font>
<a name='L110'> <b>else</b>
<a name='L111'> <font color='red'>{</font>
<a name='L112'> major_root = <a href='../S/96.html#L51' title='Defined at 51 in tools/build.c.'>DEFAULT_MAJOR_ROOT</a>;
<a name='L113'> minor_root = <a href='../S/96.html#L52' title='Defined at 52 in tools/build.c.'>DEFAULT_MINOR_ROOT</a>;
<a name='L114'>
<a name='L115'> <font color='red'>}</font>
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