u_mimetypes.pas

linux program to read packet data

(*
 * One Way Network Sniffer (OWNS)
 * Copyright (C) 2001-2002 OWNS
 *
 * http://owns.sourceforge.net/
 * http://www.owns.st
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *)

(*
 * $Id: u_MimeTypes.pas,v 1.5 2001/08/18 18:01:43 owns Exp $
 * represents a mime type
 * the function guessContentFromType guess the content from data given 
 *)

unit u_MimeTypes;
interface
uses SysUtils;

type
  TMimeType = class
  private
    FMediaType : String;
    FSubType   : String;
    FExt       : String;
    FContentType : String;
    function getText : String;
    procedure setContentType(p_ContentType : String);
    function getExt : String;
  public
    constructor create; overload;
    constructor create(p_ContentType : String); overload;
    property ContentType : String read FContentType write setContentType; // ex : image/jpeg ; des param鑤res
    property MediaType : String read FMediaType; // ex : image
    property SubType : String read FSubType;     // ex : jpeg
    property Text : String read getText;         // ex : image/jpeg
    property Ext : String read getExt;           // ex : jpg
  end;

function guessContentTypeFromContent(p_Content : PChar) : string;

implementation


// try to determine the mime type from the content
// returns '' if it has not been determined
// p_COntent must be 8 bytes at least
// (see URLConnection.guessContentTypeFromStream in Java)
function guessContentTypeFromContent(p_Content : PChar) : string;
var
  c1, c2, c3, c4, c5, c6, c7, c8 : Char;
begin
  c1 := p_Content[0];
  c2 := p_Content[1];
  c3 := p_Content[2];
  c4 := p_Content[3];
  c5 := p_Content[4];
  c6 := p_Content[5];
  c7 := p_Content[6];
  c8 := p_Content[7];
  result := '';
  if (c1 = 'G') and (c2 = 'I') and (c3 = 'F')and (c4 = '8') then
    result := 'image/gif'
  else
  if (c1 = '#') and (c2 = 'd') and (c3 = 'e')and (c4 = 'f') then
    result := 'image/x-bitmap'
  else
  if (c1 = '!') and (c2 = ' ') and (c3 = 'X')and (c4 = 'P')
     and (c5 = 'M') and (c6 = '2') then
    result := 'image/x-pixmap'
  else
  if (c1 = #137) and (c2 = #80) and (c3 = #78) and (c4 = #71) and (c5 = #13) and
     (c6 = #10) and (c7 = #26) and (c8 = #10) then
    result := 'image/png'
  else
  if (c1 = #$2E) and (c2 = #$73) and (c3 = #$6E) and (c4 = #$64) then
    result := 'audio/basic'  // .au format, big endian
  else
  if (c1 = #$64) and (c2 = #$6E) and (c3 = #$73) and (c4 = #$2E) then
    result := 'audio/basic'  // .au format, little endian
  else
  if (c1 = '<') then
  begin
    if ((c2 = '!')) or
       ((c2 = 'h') and (c3 = 't') and (c4 = 'm') and (c5 = 'l')) or
       ((c2 = 'h') and (c3 = 'e') and (c4 = 'a') and (c5 = 'd')) or
       ((c2 = 'b') and (c3 = 'o') and (c4 = 'd') and (c5 = 'y')) or
       ((c2 = 'H') and (c3 = 'T') and (c4 = 'M') and (c5 = 'L')) or
       ((c2 = 'H') and (c3 = 'E') and (c4 = 'A') and (c5 = 'D')) or
       ((c2 = 'B') and (c3 = 'O') and (c4 = 'D') and (c5 = 'Y')) then
        result := 'text/html'
    else
    if (c2 = '?') and (c3 = 'x') and (c4 = 'm') and (c5 = 'l') and (c6 = ' ') then
      result := 'application/xml';
  end
  else
  if (c1 = #$FF) and (c2 = #$D8) and (c3 = #$FF) and (c4 = #$E0) then
    result := 'image/jpeg'
  else
  if (c1 = #$FF) and (c2 = #$D8) and (c3 = #$FF) and (c4 = #$EE) then
    result := 'image/jpg'
  else
  if (c1 = 'R') and (c2 = 'a') and (c3 = 'r') and (c4 = '!') then
    result := 'application/x-rar'
  else
  if (c1 = 'F') and (c2 = 'W') and (c3 = 'S')then
    result := 'application/x-shockwave-flash'
  else
  if (c1 = 'M') and (c2 = 'S') and (c3 = 'C') and (c4 = 'F') then
    result := 'application/cab'
  else
  if (c1 = 'M') and (c2 = 'Z') then
    result := 'application/x-msdos-program'
  else
  if (c1 = 'P') and (c2 = 'K') and (c3 = #$03) and (c4 = #$04) then
    result := 'application/zip'
  else
  if (c1 = 'B') and (c2 = 'M') then
    result := 'image/bmp';
end;

constructor TMimeType.create;
begin

end;

constructor TMimeType.create(p_ContentType : String);
begin
  setContentType(p_ContentType);
end;

function TMimeType.getText : String;
begin
  result := FMediaType+'/'+FSubType;
end;

const
  kSubTypesImages : array[0..6,0..1] of string =
  (('gif','gif'),
   ('jpeg','jpg'),
   ('pjpeg','jpg'),
   ('png','png'),
   ('bmp','bmp'),
   ('tiff','tiff'),
   ('x-xbitmap','xbm'));

  kSubTypesText : array[0..4,0..1] of string =
  (('html','html'),
   ('plain','txt'),
   ('xml','xml'),
   ('css','css'),
   ('javascript','js'));

  kSubTypesAudio : array[0..8,0..1] of string =
  (('mpeg','mp3'),
   ('x-midi','mid'),
   ('midi','mid'),
   ('mid','mid'),
   ('x-pn-realaudio','ra'),
   ('x-mpeg','mp3'),
   ('x-wav','wav'),
   ('x-pn-realaudio-plugin','rm'),
   ('basic','snd'));

  kSubTypesApplication : array[0..21,0..1] of string =
  (('zip','zip'),
   ('x-zip-compressed','zip'),
   ('x-javascript','js'),
   ('pdf','pdf'),
   ('x-shockwave-flash','swf'),
   ('octet-stream','stream'),
   ('x-unknown-content-type','unk'),
   ('x-rar','rar'),
   ('x-rar-compressed','rar'),
   ('x-avc','avc'), // fichiers avp
   ('x-arj-compressed','arj'),
   ('x-compressed','gz'),
   ('x-pointplus','css'),
   ('x-tar','tar'),
   ('x-rpm','rpm'),
   ('msword','doc'),
   ('java-vm','class'),
   ('x-java-archive','jar'),
   ('x-gzip','gz'),
   ('x-msdownload','exe'),
   ('x-msdos-program','exe'),
   ('cab','cab'));

  kSubTypesVideo : array[0..4,0..1] of string =
  (('mpeg','mpeg'),
   ('x-msvideo','avi'),
   ('quicktime','qt'),
   ('msvideo','avi'),
   ('x-ms-asf','asf'));

  kSubTypesMessage : array[0..0,0..1] of string =
  (
   ('rfc822','eml'));  // celui-l