我自闲庭信步,悠然自得,不亦乐乎.

                                       ------ Keep life simple
GMail/GTalk/MSN:huyi.zg@gmail.com

 

2007年5月30日

发布一个日语汉字假名转换软件给大家

主要使用了微软的WTL和IME技术,相关链接:
http://www.cppblog.com/huyi/archive/2006/03/15/4207.html

下载地址:
http://www.cppblog.com/Files/huyi/kanji.rar

使用方式:
选中不知道读音的日文汉字(中国汉字无效),然后Ctrl+C即可。在系统托盘图标上点击左键,可以打开关闭监视功能。

软件截屏:



2007年6月11日
放出1.5版,改动如下:
1.美化了界面,改进了前一版本中显示错位的问题。
2.3秒后查询窗口自动小时。
3.做了部分过滤,能过滤掉许多非日文汉字的东西。
4.左键默认立即关闭窗口,右键定住窗口,使之不会自动消失。
新的截图就不放出了,总之漂亮了很多,希望大家继续支持。

posted @ 2007-05-30 11:03 HuYi 阅读(12494) | 评论 (18)编辑 收藏

2006年12月22日

将成员函数作为std::for_each的第三个参数

vector<Book> books;
void CBookEditDlg::ForEachBookFunctor(Book book)
{
    ......
}
for_each(books.begin(), books.end(), std::bind1st(mem_fun(&CBookEditDlg::ForEachBookFunctor), this));

关键点在于mem_fun和bind1st的使用。

for_each的实现中最核心的一个调用:functor(*iterater);
由于类非静态成员函数,必须在实例上调用:(instance->*pfn)(params);
所以for_each无法直接使用传过去的函数地址,函数指针的第一个参数是类的一个实例指针(this指针),所以必须想办法把这个指针传过去(使用std::bind1st)

关于mem_fun的一些资料,请参考
http://www.stlchina.org/documents/EffectiveSTL/files/item_41.html

对于带两个以上参数的成员函数,用stl是不能达到目的的,因为mem_fun只能生成不带参数,或者是仅带一个参数的函数对象(functor),bind1st和bind2st也只能对第一个或者是第二个参数进行绑定。
要实现对任意数量参数的成员函数生成functor,必须对stl进行扩展,所幸boost已经做到了这点,boost::bind和boost::mem_fn就是更加泛化的std::bind1st和std::mem_func

    void ForEachClassFunctor(Class c, CTreeItem treeItem)
    {
        treeView.InsertItem(c.name.c_str(), treeItem, NULL);
    }

    void ForEachBookFunctor(Book book)
    {
        CTreeItem treeItem = treeView.InsertItem(book.name.c_str(), NULL, NULL);
        vector<Class> v;
        v.push_back(Class(0,0,"nameClass1", "titleClass1"));
        for_each(v.begin(), v.end(),
            boost::bind(boost::mem_fn(&CBookEditDlg::ForEachClassFunctor), this, _1, treeItem));
    }

posted @ 2006-12-22 15:10 HuYi 阅读(5685) | 评论 (3)编辑 收藏

UTF-8与Unicode的相互转换

今天用到了Sqlite,由于它内部是使用UTF-8编码,所以在Windows应用中出现了乱码。
简单的搜索了一下,相互转换的方法很多,我觉得比较好的,是
http://www.vckbase.com/document/viewdoc/?id=1444

我稍微改进了一下:

    static WCHAR* UTF82Unicode(WCHAR* pBuffer,char *pSource, int buff_size)
    {
        int i, j, max;
        char* uchar = (char *)pBuffer;
        max = buff_size - 2;
        for(i = 0, j = 0; pSource[j] != '\0'; i += 2, j += 3)
        {
            if (i > max) {
                break;
            }
            uchar[i+1] = ((pSource[j] & 0x0F) << 4) + ((pSource[j+1] >> 2) & 0x0F);
            uchar[i] = ((pSource[j+1] & 0x03) << 6) + (pSource[j+2] & 0x3F);
        }
        uchar[i] = '\0';
        uchar[i+1] = '\0';
        return pBuffer;
    }

在Windows中的话,还有更简单的方法完成转换:
比如从UTF-8到Unicode:
    WCHAR buff[255];
    MultiByteToWideChar(CP_UTF8, 0, argv[i], -1, buff, sizeof(buff));
    item.name = W2A(buff);

argv[i]是要转换的字节数组

posted @ 2006-12-22 15:09 HuYi 阅读(1832) | 评论 (1)编辑 收藏

2006年10月14日

关于文件操作的封装处理

File类本身并不持有文件句柄,它只是集中了一系列对文件的操作方法,如Create,Open等等。这些方法全部都是静态的,也不进行任何的安全检测,仅仅是直接调用pspsdk来完成任务,如果出现错误,则返回负值。
File的Open等方法可以创建针对指定文件读写的流对象FileStream,句柄由FileStream自己创建和持有管理,File::Open只是传达路径信息。
可以把File看作是一个门面,集中了对文件的所有操作,并且不需要创建File对象就可以直接执行这些操作。所以说File为文件的单一操作提供了快捷简便的方式。
除了几个创建FileStream流的操作外,其他操作都不会长期占用句柄资源,遵循"句柄创建-执行具体操作-释放句柄"的步骤。

如果需要频繁的操作文件,则需要一个类来长期持有句柄,避免经常性的打开和关闭文件,故此引入FileInfo类。FileInfo执行Append等操作时,都是使用事先打开的文件句柄。
同时,FileInfo也可以创建FileStream实例,但这个时候,文件的句柄生命周期应该由FileInfo来管理,FileStream可以使用这个句柄,但不能结束其生命周期,FileStream::Close()方法仅仅使这个流处于关闭(不可读写)状态,但并不实际关闭文件句柄。
这种情况下,FileInfo所创建的FileStream::Close()的行为和前面File所创建的FileStream::Close()行为有差异。因为File并不持有句柄,所以它创建了FileStream对象后,句柄应该由FileStream来管理。但FileInfo所创建的FileStream是使用的FileInfo所创建好的句柄,所以它并不对此句柄负责。

实现策略:
1.使用基于继承的多态或基于模板的静多态。
2.使用函数回调。把Close做成调用函数指针,通过不同的FileStream构造函数调用,来设置指针指向不同的Close函数实现。(关闭句柄或不关闭句柄)
这两种做法的优劣性正在考证中,请提出意见。


补充:File和FileInfo的关系在dotnet中也有体现,不过他们主要是从错误检测方面考虑。
最终的目的是要为客户提供一个统一的界面,所以不能用太复杂的模板。

经过慎重考虑,我还是决定用虚函数,放弃了模板。

posted @ 2006-10-14 16:45 HuYi 阅读(1087) | 评论 (0)编辑 收藏

2006年10月13日

为什么要用“((”取代“(”?

在做日志接口的时候,真实的接口函数应该是如下样式的:
__static_logger__.log(int level,const char* fmt, ...);
这里使用了printf类似的技术:可变参数。
这个技术可以动态的替换字符串fmt中的内容。
同时,这个方法可能会被重载,用于不需要可变参数的情况:
__static_logger__.log(int level,const char* fmt);

通常,我们还会定义一些辅助用的宏:
#define KLOG(X) \
    do { \
        KDBG::printf X; \
    } while (0)

使用的时候,必须按照下面的格式:
KLOG((LM_ERROR, "%s\n", strerror(errno)));
注意,使用了双层的括号“((”

为什么不把宏改成:
#define KLOG(X,Y,...) \
    do { \
        KDBG::log(X,Y,__VA_ARGS__); \
    } while (0)s
从而按如下的“标准形式”来使用LOG呢?
KLOG(LM_ERROR, "%s\n", strerror(errno));


答案是宏不能像函数那样重载,KLOG宏只能有一个,就是最后定义的那个,也就是能接受的参数个数是固定的。

posted @ 2006-10-13 13:50 HuYi 阅读(1619) | 评论 (1)编辑 收藏

2006年7月31日

二环十三郎传说中的装备

1.8T发动机总成 55000元
大众原厂MO250变速箱 20000
1.8T半轴 3000
BMC进汽 2500
运动款宝来凸轮轴 3000
运动款宝来涡轮 9800
SUPERSPRING全段排气 9800
尾牙 7000
法雷奥离合器 3000
原厂180匹电脑程序 2800
DENSO火花塞 600
HKS泄气阀 2800
4公斤回油阀 300

SPAXJ减震器 7000
NEUSPEED前后防倾杆 2000
原厂前312mm后256mm刹车盘9000
仿RS418寸轮圈 3200
米其林PS2轮胎 10000

自加工前后包围 3000
自制机头盖 1500
氙气大灯 1800
HKS涡轮压力表 900
SPARCO方向盘 1800
4MOTION档把 1200

posted @ 2006-07-31 18:26 HuYi 阅读(1101) | 评论 (3)编辑 收藏

2006年7月28日

怎么才能成一名架构师?

这个题目大了点,不适合我这种刚参加工作不久的人来回答。

Blog很久没有更新了,答应了朋友写点这方面的看法,就在这里表达一下自己的意见,抛砖引玉。

架构师也有不同的类型。我主要想讨论软件方面的架构师。

一是体系结构级的,要负责产品的部署,硬件,网络等等很多整体上的东西,这一类不仅需要扎实而广泛的基础知识,更需要经验,特别是在大企业工作的经验。这一点也是在单位看了一些日本人的设计,才慢慢体会到。

二是软件本身的架构,是我想重点讨论的。
软件应用的领域不同,架构也有很大的差别,嵌入式有嵌入式的做法,电信软件有电信软件的做法,企业应用有企业应用的做法,桌面有桌面的做法。如果要全部讨论,我没有这个实力,所以只说最常见的企业应用开发和桌面软件开发。

最重要的基础,我觉得是OO,不管实际编程设计是否是OO的,都应该了解,具备OO的思想。强调一下,采用最合适的思想和手段来开发软件,而不一定非要用OO,或者是非不用OO。我比较坚信的一点是,当代及未来的程序员,或许在实际工作中不需要用到OO,比如说搞嵌入式开发,或者Linux底层方面开发的(事实上,Linux中也用到了OO,比如文件系统),但必须是了解OO的。

一,万丈高楼从地起,一力承担靠地基

1。敏捷软件开发



为什么推荐这本呢?其实是推荐这本书的前半部分。因为它的前一半一定可以让人耳目一新,让人知道OO除了封装,继承,多态以外,还有更多的东西,而且这本书十分容易懂。


2。《OOP启思录》


绝对的经典,不过就比较枯燥了。全部是关于OO的理论及设计准则。所以虽然非常基础,但并没有作为第一步推荐的书。看这个,需要对OO有了一定的了解,才能坚持下去。

二,顺藤摸瓜,寻根究底
初学的人常说,OO就是对象,就是封装继承多态。对,没错,但语言是怎么支持这些OO特性的呢?

1。深度探索C++对象模型



我们CPP粉丝有福了,本书探索了C++对OO的支持,底层对象模型实现等非常有价值的内容。同样是相对枯燥的,而且颇具难度,所以学习之前最好对C++这门语言熟悉,而且有兴趣去了解它的本质。
对于非CPP帮派成员,看这个可能比较困难,但我也找不出其他替代的学习书籍了,知道的朋友请补充。

第三,练招
内功基础有了,就该练习剑招拳谱了。

软件设计的剑谱,就是设计模式,就是前人总结出来的套路,当然你也可以自创。但自创之前,一定要多看多想,充分吸取前人的精髓。

1,Java与模式



国人写的不得不推荐的一本好书(也有很多人说他太啰嗦)。我初学的时候,一上来就是Gof的传世经典,结果薄薄的一本册子,花了我整整一年的时间,还觉得理解不够。当我看了一遍Java与模式,豁然开朗,如果先有了这个,一定不会觉得设计模式那么难。

2。设计模式:可复用面向对象软件的基础

前面所提到的“传世之作”,为什么那么经典?因为句句话都是经典,可以说没有一句废话(《java与模式》就被人说成废话连篇)。
java与模式,我看完后就送女朋友了,而这本书,我却保存了起来,作为手册查,这就是我的用法。





未完待续。。。

posted @ 2006-07-28 00:02 HuYi 阅读(1159) | 评论 (1)编辑 收藏

2006年6月20日

Linux启动协议Ver.2.04

       THE LINUX/I386 BOOT PROTOCOL
       ----------------------------

      H. Peter Anvin <hpa@zytor.com>
   Last update 2005-09-02

On the i386 platform, the Linux kernel uses a rather complicated boot
convention.  This has evolved partially due to historical aspects, as
well as the desire in the early days to have the kernel itself be a
bootable image, the complicated PC memory model and due to changed
expectations in the PC industry caused by the effective demise of
real-mode DOS as a mainstream operating system.

Currently, four versions of the Linux/i386 boot protocol exist.

Old kernels: zImage/Image support only.  Some very early kernels
  may not even support a command line.

Protocol 2.00: (Kernel 1.3.73) Added bzImage and initrd support, as
  well as a formalized way to communicate between the
  boot loader and the kernel.  setup.S made relocatable,
  although the traditional setup area still assumed
  writable.

Protocol 2.01: (Kernel 1.3.76) Added a heap overrun warning.

Protocol 2.02: (Kernel 2.4.0-test3-pre3) New command line protocol.
  Lower the conventional memory ceiling. No overwrite
  of the traditional setup area, thus making booting
  safe for systems which use the EBDA from SMM or 32-bit
  BIOS entry points.  zImage deprecated but still
  supported.

Protocol 2.03: (Kernel 2.4.18-pre1) Explicitly makes the highest possible
  initrd address available to the bootloader.

Protocol 2.04: (Kernel 2.6.14) Extend the syssize field to four bytes.


**** MEMORY LAYOUT

The traditional memory map for the kernel loader, used for Image or
zImage kernels, typically looks like:

 |    |
0A0000 +------------------------+
 |  Reserved for BIOS  | Do not use.  Reserved for BIOS EBDA.
09A000 +------------------------+
 |  Stack/heap/cmdline  | For use by the kernel real-mode code.
098000 +------------------------+ 
 |  Kernel setup   | The kernel real-mode code.
090200 +------------------------+
 |  Kernel boot sector  | The kernel legacy boot sector.
090000 +------------------------+
 |  Protected-mode kernel | The bulk of the kernel image.
010000 +------------------------+
 |  Boot loader   | <- Boot sector entry point 0000:7C00
001000 +------------------------+
 |  Reserved for MBR/BIOS |
000800 +------------------------+
 |  Typically used by MBR |
000600 +------------------------+
 |  BIOS use only  |
000000 +------------------------+


When using bzImage, the protected-mode kernel was relocated to
0x100000 ("high memory"), and the kernel real-mode block (boot sector,
setup, and stack/heap) was made relocatable to any address between
0x10000 and end of low memory. Unfortunately, in protocols 2.00 and
2.01 the command line is still required to live in the 0x9XXXX memory
range, and that memory range is still overwritten by the early kernel.
The 2.02 protocol resolves that problem.

It is desirable to keep the "memory ceiling" -- the highest point in
low memory touched by the boot loader -- as low as possible, since
some newer BIOSes have begun to allocate some rather large amounts of
memory, called the Extended BIOS Data Area, near the top of low
memory.  The boot loader should use the "INT 12h" BIOS call to verify
how much low memory is available.

Unfortunately, if INT 12h reports that the amount of memory is too
low, there is usually nothing the boot loader can do but to report an
error to the user.  The boot loader should therefore be designed to
take up as little space in low memory as it reasonably can.  For
zImage or old bzImage kernels, which need data written into the
0x90000 segment, the boot loader should make sure not to use memory
above the 0x9A000 point; too many BIOSes will break above that point.


**** THE REAL-MODE KERNEL HEADER

In the following text, and anywhere in the kernel boot sequence, "a
sector" refers to 512 bytes.  It is independent of the actual sector
size of the underlying medium.

The first step in loading a Linux kernel should be to load the
real-mode code (boot sector and setup code) and then examine the
following header at offset 0x01f1.  The real-mode code can total up to
32K, although the boot loader may choose to load only the first two
sectors (1K) and then examine the bootup sector size.

The header looks like:

Offset Proto Name  Meaning
/Size

01F1/1 ALL(1 setup_sects The size of the setup in sectors
01F2/2 ALL root_flags If set, the root is mounted readonly
01F4/4 2.04+(2 syssize  The size of the 32-bit code in 16-byte paras
01F8/2 ALL ram_size DO NOT USE - for bootsect.S use only
01FA/2 ALL vid_mode Video mode control
01FC/2 ALL root_dev Default root device number
01FE/2 ALL boot_flag 0xAA55 magic number
0200/2 2.00+ jump  Jump instruction
0202/4 2.00+ header  Magic signature "HdrS"
0206/2 2.00+ version  Boot protocol version supported
0208/4 2.00+ realmode_swtch Boot loader hook (see below)
020C/2 2.00+ start_sys The load-low segment (0x1000) (obsolete)
020E/2 2.00+ kernel_version Pointer to kernel version string
0210/1 2.00+ type_of_loader Boot loader identifier
0211/1 2.00+ loadflags Boot protocol option flags
0212/2 2.00+ setup_move_size Move to high memory size (used with hooks)
0214/4 2.00+ code32_start Boot loader hook (see below)
0218/4 2.00+ ramdisk_image initrd load address (set by boot loader)
021C/4 2.00+ ramdisk_size initrd size (set by boot loader)
0220/4 2.00+ bootsect_kludge DO NOT USE - for bootsect.S use only
0224/2 2.01+ heap_end_ptr Free memory after setup end
0226/2 N/A pad1  Unused
0228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line
022C/4 2.03+ initrd_addr_max Highest legal initrd address

(1) For backwards compatibility, if the setup_sects field contains 0, the
    real value is 4.

(2) For boot protocol prior to 2.04, the upper two bytes of the syssize
    field are unusable, which means the size of a bzImage kernel
    cannot be determined.

If the "HdrS" (0x53726448) magic number is not found at offset 0x202,
the boot protocol version is "old".  Loading an old kernel, the
following parameters should be assumed:

 Image type = zImage
 initrd not supported
 Real-mode kernel must be located at 0x90000.

Otherwise, the "version" field contains the protocol version,
e.g. protocol version 2.01 will contain 0x0201 in this field.  When
setting fields in the header, you must make sure only to set fields
supported by the protocol version in use.

The "kernel_version" field, if set to a nonzero value, contains a
pointer to a null-terminated human-readable kernel version number
string, less 0x200.  This can be used to display the kernel version to
the user.  This value should be less than (0x200*setup_sects).  For
example, if this value is set to 0x1c00, the kernel version number
string can be found at offset 0x1e00 in the kernel file.  This is a
valid value if and only if the "setup_sects" field contains the value
14 or higher.

Most boot loaders will simply load the kernel at its target address
directly.  Such boot loaders do not need to worry about filling in
most of the fields in the header.  The following fields should be
filled out, however:

  vid_mode:
 Please see the section on SPECIAL COMMAND LINE OPTIONS.

  type_of_loader:
 If your boot loader has an assigned id (see table below), enter
 0xTV here, where T is an identifier for the boot loader and V is
 a version number.  Otherwise, enter 0xFF here.

 Assigned boot loader ids:
 0  LILO
 1  Loadlin
 2  bootsect-loader
 3  SYSLINUX
 4  EtherBoot
 5  ELILO
 7  GRuB
 8  U-BOOT

 Please contact <hpa@zytor.com> if you need a bootloader ID
 value assigned.

  loadflags, heap_end_ptr:
 If the protocol version is 2.01 or higher, enter the
 offset limit of the setup heap into heap_end_ptr and set the
 0x80 bit (CAN_USE_HEAP) of loadflags.  heap_end_ptr appears to
 be relative to the start of setup (offset 0x0200).

  setup_move_size:
 When using protocol 2.00 or 2.01, if the real mode
 kernel is not loaded at 0x90000, it gets moved there later in
 the loading sequence.  Fill in this field if you want
 additional data (such as the kernel command line) moved in
 addition to the real-mode kernel itself.

  ramdisk_image, ramdisk_size:
 If your boot loader has loaded an initial ramdisk (initrd),
 set ramdisk_image to the 32-bit pointer to the ramdisk data
 and the ramdisk_size to the size of the ramdisk data.

 The initrd should typically be located as high in memory as
 possible, as it may otherwise get overwritten by the early
 kernel initialization sequence.  However, it must never be
 located above the address specified in the initrd_addr_max
 field. The initrd should be at least 4K page aligned.

  cmd_line_ptr:
 If the protocol version is 2.02 or higher, this is a 32-bit
 pointer to the kernel command line.  The kernel command line
 can be located anywhere between the end of setup and 0xA0000.
 Fill in this field even if your boot loader does not support a
 command line, in which case you can point this to an empty
 string (or better yet, to the string "auto".)  If this field
 is left at zero, the kernel will assume that your boot loader
 does not support the 2.02+ protocol.

  ramdisk_max:
 The maximum address that may be occupied by the initrd
 contents.  For boot protocols 2.02 or earlier, this field is
 not present, and the maximum address is 0x37FFFFFF.  (This
 address is defined as the address of the highest safe byte, so
 if your ramdisk is exactly 131072 bytes long and this field is
 0x37FFFFFF, you can start your ramdisk at 0x37FE0000.)


**** THE KERNEL COMMAND LINE

The kernel command line has become an important way for the boot
loader to communicate with the kernel.  Some of its options are also
relevant to the boot loader itself, see "special command line options"
below.

The kernel command line is a null-terminated string currently up to
255 characters long, plus the final null.  A string that is too long
will be automatically truncated by the kernel, a boot loader may allow
a longer command line to be passed to permit future kernels to extend
this limit.

If the boot protocol version is 2.02 or later, the address of the
kernel command line is given by the header field cmd_line_ptr (see
above.)  This address can be anywhere between the end of the setup
heap and 0xA0000.

If the protocol version is *not* 2.02 or higher, the kernel
command line is entered using the following protocol:

 At offset 0x0020 (word), "cmd_line_magic", enter the magic
 number 0xA33F.

 At offset 0x0022 (word), "cmd_line_offset", enter the offset
 of the kernel command line (relative to the start of the
 real-mode kernel).
 
 The kernel command line *must* be within the memory region
 covered by setup_move_size, so you may need to adjust this
 field.


**** SAMPLE BOOT CONFIGURATION

As a sample configuration, assume the following layout of the real
mode segment (this is a typical, and recommended layout):

 0x0000-0x7FFF Real mode kernel
 0x8000-0x8FFF Stack and heap
 0x9000-0x90FF Kernel command line

Such a boot loader should enter the following fields in the header:

 unsigned long base_ptr; /* base address for real-mode segment */

 if ( setup_sects == 0 ) {
  setup_sects = 4;
 }

 if ( protocol >= 0x0200 ) {
  type_of_loader = <type code>;
  if ( loading_initrd ) {
   ramdisk_image = <initrd_address>;
   ramdisk_size = <initrd_size>;
  }
  if ( protocol >= 0x0201 ) {
   heap_end_ptr = 0x9000 - 0x200;
   loadflags |= 0x80; /* CAN_USE_HEAP */
  }
  if ( protocol >= 0x0202 ) {
   cmd_line_ptr = base_ptr + 0x9000;
  } else {
   cmd_line_magic = 0xA33F;
   cmd_line_offset = 0x9000;
   setup_move_size = 0x9100;
  }
 } else {
  /* Very old kernel */

  cmd_line_magic = 0xA33F;
  cmd_line_offset = 0x9000;

  /* A very old kernel MUST have its real-mode code
     loaded at 0x90000 */

  if ( base_ptr != 0x90000 ) {
   /* Copy the real-mode kernel */
   memcpy(0x90000, base_ptr, (setup_sects+1)*512);
   /* Copy the command line */
   memcpy(0x99000, base_ptr+0x9000, 256);

   base_ptr = 0x90000;   /* Relocated */
  }

  /* It is recommended to clear memory up to the 32K mark */
  memset(0x90000 + (setup_sects+1)*512, 0,
         (64-(setup_sects+1))*512);
 }


**** LOADING THE REST OF THE KERNEL

The 32-bit (non-real-mode) kernel starts at offset (setup_sects+1)*512
in the kernel file (again, if setup_sects == 0 the real value is 4.)
It should be loaded at address 0x10000 for Image/zImage kernels and
0x100000 for bzImage kernels.

The kernel is a bzImage kernel if the protocol >= 2.00 and the 0x01
bit (LOAD_HIGH) in the loadflags field is set:

 is_bzImage = (protocol >= 0x0200) && (loadflags & 0x01);
 load_address = is_bzImage ? 0x100000 : 0x10000;

Note that Image/zImage kernels can be up to 512K in size, and thus use
the entire 0x10000-0x90000 range of memory.  This means it is pretty
much a requirement for these kernels to load the real-mode part at
0x90000.  bzImage kernels allow much more flexibility.


**** SPECIAL COMMAND LINE OPTIONS

If the command line provided by the boot loader is entered by the
user, the user may expect the following command line options to work.
They should normally not be deleted from the kernel command line even
though not all of them are actually meaningful to the kernel.  Boot
loader authors who need additional command line options for the boot
loader itself should get them registered in
Documentation/kernel-parameters.txt to make sure they will not
conflict with actual kernel options now or in the future.

  vga=<mode>
 <mode> here is either an integer (in C notation, either
 decimal, octal, or hexadecimal) or one of the strings
 "normal" (meaning 0xFFFF), "ext" (meaning 0xFFFE) or "ask"
 (meaning 0xFFFD).  This value should be entered into the
 vid_mode field, as it is used by the kernel before the command
 line is parsed.

  mem=<size>
 <size> is an integer in C notation optionally followed by K, M
 or G (meaning << 10, << 20 or << 30).  This specifies the end
 of memory to the kernel. This affects the possible placement
 of an initrd, since an initrd should be placed near end of
 memory.  Note that this is an option to *both* the kernel and
 the bootloader!

  initrd=<file>
 An initrd should be loaded.  The meaning of <file> is
 obviously bootloader-dependent, and some boot loaders
 (e.g. LILO) do not have such a command.

In addition, some boot loaders add the following options to the
user-specified command line:

  BOOT_IMAGE=<file>
 The boot image which was loaded.  Again, the meaning of <file>
 is obviously bootloader-dependent.

  auto
 The kernel was booted without explicit user intervention.

If these options are added by the boot loader, it is highly
recommended that they are located *first*, before the user-specified
or configuration-specified command line.  Otherwise, "init=/bin/sh"
gets confused by the "auto" option.


**** RUNNING THE KERNEL

The kernel is started by jumping to the kernel entry point, which is
located at *segment* offset 0x20 from the start of the real mode
kernel.  This means that if you loaded your real-mode kernel code at
0x90000, the kernel entry point is 9020:0000.

At entry, ds = es = ss should point to the start of the real-mode
kernel code (0x9000 if the code is loaded at 0x90000), sp should be
set up properly, normally pointing to the top of the heap, and
interrupts should be disabled.  Furthermore, to guard against bugs in
the kernel, it is recommended that the boot loader sets fs = gs = ds =
es = ss.

In our example from above, we would do:

 /* Note: in the case of the "old" kernel protocol, base_ptr must
    be == 0x90000 at this point; see the previous sample code */

 seg = base_ptr >> 4;

 cli(); /* Enter with interrupts disabled! */

 /* Set up the real-mode kernel stack */
 _SS = seg;
 _SP = 0x9000; /* Load SP immediately after loading SS! */

 _DS = _ES = _FS = _GS = seg;
 jmp_far(seg+0x20, 0); /* Run the kernel */

If your boot sector accesses a floppy drive, it is recommended to
switch off the floppy motor before running the kernel, since the
kernel boot leaves interrupts off and thus the motor will not be
switched off, especially if the loaded kernel has the floppy driver as
a demand-loaded module!


**** ADVANCED BOOT TIME HOOKS

If the boot loader runs in a particularly hostile environment (such as
LOADLIN, which runs under DOS) it may be impossible to follow the
standard memory location requirements.  Such a boot loader may use the
following hooks that, if set, are invoked by the kernel at the
appropriate time.  The use of these hooks should probably be
considered an absolutely last resort!

IMPORTANT: All the hooks are required to preserve %esp, %ebp, %esi and
%edi across invocation.

  realmode_swtch:
 A 16-bit real mode far subroutine invoked immediately before
 entering protected mode.  The default routine disables NMI, so
 your routine should probably do so, too.

  code32_start:
 A 32-bit flat-mode routine *jumped* to immediately after the
 transition to protected mode, but before the kernel is
 uncompressed.  No segments, except CS, are set up; you should
 set them up to KERNEL_DS (0x18) yourself.

 After completing your hook, you should jump to the address
 that was in this field before your boot loader overwrote it.

posted @ 2006-06-20 14:46 HuYi 阅读(1520) | 评论 (0)编辑 收藏

2006年5月31日

Google为什么会被封锁?

很早以前就听说过Google被封锁的消息,因为自己没有遇到过,也不太相信真会有这样的事情,多可笑呀.

不过自从感受到了一次sourceforge被封,就觉得在中国,或许真会发生这样的事情.

今天,google终于挂了,gmail也挂了,我也无语了.

打听了一下,全国好多地方的网友都访问不了google了.

业内最令人鄙视的案例莫过于微软靠捆绑IE搞跨了网景,微软的这个脾气至今还是大家鄙视它的主因.但是请注意,微软并没有禁止Windows用户使用网景的服务!!!!

希望中国的google事件不要成为他国的笑柄.

http://post.baidu.com/f?kz=103530334

仅以此贴纪念Google GMail  GTalk




支持Google的朋友请在这里签名吧!

希望zf早点把GMail和GTalk还给我们!!

posted @ 2006-05-31 23:28 HuYi 阅读(5612) | 评论 (13)编辑 收藏

2006年5月26日

这回看见好贴子就有话说了^^

     摘要: 看了楼主的帖子 , 不由得精神 为 之一振 , 自 觉 七 经 八脉 ...  阅读全文

posted @ 2006-05-26 10:37 HuYi 阅读(1007) | 评论 (1)编辑 收藏

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