project/captive/doc/Architecture.pm

   1 # $Id$
   2 # Captive project doc Architecture page Perl template.
   3 # Copyright (C) 2003-2005 Jan Kratochvil <project-www.jankratochvil.net@jankratochvil.net>
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; exactly version 2 of June 1991 is required
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17
  18
  19 package project::captive::doc::Architecture;
  20 require 5.6.0;  # at least 'use warnings;' but we need some 5.6.0+ modules anyway
  21 our $VERSION=do { my @r=(q$Revision$=~/\d+/g); sprintf "%d.".("%03d"x$#r),@r; };
  22 our $CVS_ID=q$Id$;
  23 use strict;
  24 use warnings;
  25
  26 use My::Web;
  27 require CGI;
  28 BEGIN { Wuse 'project::captive::doc::Macros'; }
  29
  30
  31 sub handler
  32 {
  33 project::captive::doc::Macros->init(
  34                 "title"=>'Captive NTFS Developer Documentation: Architecture',
  35                 "rel_prev"=>'About.pm',
  36                 "rel_next"=>'Components.pm',
  37                 );
  38
  39
  40 print <<"HERE";
  41
  42
  43 <h1>Architecture</h1>
  44
  45         <p>The principle of the
  46         project lies in the glue between
  47         <span class="productname">Microsoft Windows NT</span> kernel space
  48         environment and $gnulinux user space process environment:</p>
  49
  50         @{[ doc_img 'arch-W32','Microsoft Windows Subsystems Architecture' ]}
  51         @{[ doc_img 'arch-captive','Captive Subsystems Architecture' ]}
  52
  53         <h2 id="existing_emulation">Existing Emulation Projects</h2>
  54
  55                 <p>There were two well-known $freespeech projects emulating W32 subsystems
  56                 to reach the compatibility with various W32 components:
  57                 $Wine and $ReactOS. Sad moment is that the goals of this project do not fit
  58                 very well into any role in those two ones. Therefore this project went
  59                 its own way of emulation:</p>
  60
  61                 <table border="0" width="100%"><tr><td align="center"><table border="1">
  62                         <caption>Emulation Projects Characteristics</caption>
  63                         <tr>
  64                                 <th>@{[ a_href '#guestosnote','Guest-OS' ]}</th>
  65                                 <th>@{[ a_href '#hostosnote' ,'Host-OS'  ]}</th>
  66                                 <th>Implements</th>
  67                                 <th>W32 kernel library</th>
  68                                 </tr>
  69                         <tr>
  70                                 <td>$Wine</td>
  71                                 <td>$gnulinux</td>
  72                                 <td>W32 user space</td>
  73                                 <td><span class="fname">ntdll.dll</span></td>
  74                                 </tr>
  75                         <tr>
  76                                 <td>$ReactOS</td>
  77                                 <td><span class="constant">i386</span> hardware</td>
  78                                 <td>W32 kernel and user space</td>
  79                                 <td><span class="fname">ntoskrnl.exe</span></td>
  80                                 </tr>
  81                         <tr style="height: 1ex;"><td colspan="4"></td></tr>
  82                         <tr>
  83                                 <td>this project</td>
  84                                 <td>$gnulinux</td>
  85                                 <td>W32 kernel</td>
  86                                 <td><span class="fname">ntoskrnl.exe</span></td>
  87                                 </tr>
  88                 </table></td></tr></table>
  89
  90                 <dl>
  91                         <dt id="guestosnote">Guest-OS</dt>
  92                         <dd>@{[ a_href 'http://www.vmware.com/support/reference/common/glossary/#guestos','Guest OS' ]}:
  93                                 An operating system that runs inside a&nbsp;virtual machine.</dd>
  94                         <dt id="hostosnote">Host  OS</dt>
  95                         <dd>@{[ a_href 'http://www.vmware.com/support/reference/common/glossary/#hostos' ,'Host  OS' ]}:
  96                                 An operating system that runs on the host machine.</dd>
  97                 </dl>
  98
  99                 <p>While $ReactOS provides the necessary W32 kernel subsystem emulation
 100                 code we also need to run such @{[ a_href '#guestosnote','Guest-OS' ]} in the
 101                 @{[ a_href '#hostosnote','Host-OS' ]} $gnulinux. Initially it was planned to
 102                 extend $Wine with the W32 kernel space emulation functionality but
 103                 fortunately <span class="author">Steven Edwards</span> pointed to the $ReactOS
 104                 which better suits the needs of this project by its already implemented W32
 105                 kernel space emulation.</p>
 106
 107                 <p>The <span id="reactos_nocare">original reasons</span> for developing
 108                 $ReactOS still make no sense to the author of this project. Free
 109                 implementation of W32 platform standalone running on the machine hardware
 110                 is no longer free as most od the W32 applications are usually closed source
 111                 and the user still looses its freedom on the application level anyway. Even
 112                 in the case of available free applications there still remains the
 113                 disadvantage of loosing the Host-OS platform availability if implemented in
 114                 the $Wine style. For these ideology incompatibilities not much effort was
 115                 made for acceptance the fixes and improvements of $ReactOS by this project.
 116                 Moreover new functionality is not being implemented to the $ReactOS part
 117                 but it is coded in Gnome style in the project specific source files
 118                 place.</p>
 119
 120                 <p>The most serious problem of $ReactOS is its dependence on the direct
 121                 <span class="constant">i386</span> hardware instead of some
 122                 @{[ a_href '#hostosnote','Host-OS' ]} as required by the goals of this project.
 123                 W32 is designed to be hardware-independent using its
 124                 <span class="fname">hal.dll</span>. Unfortunately $ReactOS does not follow
 125                 this design and thus there are needed various patches and replaces of its
 126                 various parts and its hardware-dependent code. Despite it $ReactOS code
 127                 base still made a big asset for this project.</p>
 128
 129                 <p>Some API functions are provided both by
 130                 <span class="fname">ntdll.dll</span> and
 131                 <span class="fname">ntoskrnl.exe</span> in W32.
 132                 <span class="author">Casper Hornstrup</span> enlightened such functions
 133                 calling conventions have to be differentiated as
 134                 <span class="fname">ntdll.dll</span> lives in the user space (low address
 135                 space &ndash; below <span class="constant">0x80000000</span>) and
 136                 <span class="fname">ntoskrnl.exe</span> in the kernel space (high address
 137                 space &ndash; above <span class="constant">0x80000000</span>). Although they
 138                 contain slightly different set of symbols (functions)
 139                 <span class="fname">ntdll.dll</span> still can be considered as a&nbsp;user
 140                 space interface to the kernel space implementation by
 141                 <span class="fname">ntoskrnl.exe</span>.</p>
 142
 143                 <p>Currently there are
 144                 no plans to ever extend the project's crossplatformity beyond the
 145                 <span class="constant">i386</span> processor
 146                         (<span class="constant">i386</span> used here as
 147                         @{[ a_href 'http://www.intel.com/','Intel' ]} architecture covering 32-bit
 148                         processors compatible with <span class="constant">i386</span>,
 149                         <span class="constant">i486</span>, ...).</p>
 150
 151
 152         <h2 id="law">Laws and Licensing Conditions</h2>
 153
 154                 <p>If you are an <span class="productname">authorized user</span> of
 155                 <span class="productname">Microsoft Windows NT</span> the laws in some
 156                 countries give you the right to fully handle the product in any way you
 157                 want. Therefore you can disassemble the product even in the case you had
 158                 to agree with the product license forbidding such disassembly as the
 159                 country laws override any such license agreement.</p>
 160
 161                 <h3 id="law_servicepack">Microsoft Service Pack</h3>
 162
 163                         <p>Sometimes you may have the legal license for
 164                         <span class="productname">Microsoft Windows NT</span>
 165                         but for various technical reasons you do not have the media and/or
 166                         installation ready at the place of intended use of this project.</p>
 167
 168                         <p>Fortunately <span class="productname">Microsoft</span> provides
 169                         $freebeer update packages for its
 170                         <span class="productname">Microsoft Windows</span> products called
 171                         <span class="productname">Service Packs</span>; the latest one is
 172                         <span class="productname">@{[ a_href 'http://www.microsoft.com/WindowsXP/pro/downloads/servicepacks/sp1/checkedbuild.asp','Microsoft Windows XP Service Pack 1a' ]}</span>.</p>
 173
 174                         <p>This downloadable file contains the full versions of the essential
 175                         files needed for the current stage of this product:
 176                         <span class="fname">ntfs.sys</span>
 177                         and
 178                         <span class="fname">ntoskrnl.exe</span>.
 179                         It even contains
 180                         <span class="fname">cdfs.sys</span> and
 181                         <span class="fname">fastfat.sys</span> for testing purposes.</p>
 182
 183                         <p><span class="productname">Service Pack</span> also contains
 184                         EULA (End User License Agreement) paper disallowing any use of
 185                         <span class="productname">Service Pack</span> outside its original
 186                         intentions. According to the laws of some countries you need to be
 187                         <span class="productname">authorized user</span> of the
 188                         <span class="productname">Microsoft Windows XP</span> product to be
 189                         allowed to use the files contained in such
 190                         <span class="productname">Service Pack</span> without the bindings of its
 191                         EULA. Even the interpretation of such laws may vary.</p>
 192
 193                         <p>It would be a&nbsp;breach of the law by the project author to provide
 194                         automatic (=hidden) functionality to download and extract the
 195                         <span class="productname">Service Pack</span> files. On the other hand it
 196                         is perfectly legal to ask user for his/her confirmation whether he/she is
 197                         really the <span class="productname">authorized user</span> of
 198                         <span class="productname">Microsoft Windows XP</span> product and
 199                         download/extract the <span class="productname">Service Pack</span> files
 200                         accordingly.</p>
 201
 202                         @{[ doc_img 'captive-install-acquire-ask','Microsoft Windows Drivers Acquire Affirmation' ]}
 203
 204
 205 HERE
 206
 207
 208 project::captive::doc::Macros->footer();
 209 }
 210 1;