/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* Author :
* Dan Winship <danw@ximian.com>
*
* Copyright 2000, Ximian, Inc. (www.ximian.com)
*
* 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 Street #330, Boston, MA 02111-1307, USA.
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include <libgnomevfs/gnome-vfs-mime.h>
#include <libgnomevfs/gnome-vfs-mime-sniff-buffer.h>
#include "mail.h"
static const char *identify_by_magic (CamelDataWrapper *data, MailDisplay *md);
/**
* mail_identify_mime_part:
* @part: a CamelMimePart
* @md: the MailDisplay @part is being shown in
*
* Try to identify the MIME type of the data in @part (which presumably
* doesn't have a useful Content-Type).
*
* Return value: the MIME type, which the caller must free, or %NULL
* if it could not be identified.
**/
char *
mail_identify_mime_part (CamelMimePart *part, MailDisplay *md)
{
const char *filename, *name_type = NULL, *magic_type = NULL;
CamelDataWrapper *data;
filename = camel_mime_part_get_filename (part);
if (filename) {
/* GNOME-VFS will misidentify TNEF attachments as MPEG */
if (!strcmp (filename, "winmail.dat"))
return g_strdup ("application/vnd.ms-tnef");
name_type = gnome_vfs_mime_type_from_name_or_default (filename, NULL);
}
data = camel_medium_get_content_object (CAMEL_MEDIUM (part));
if (!camel_data_wrapper_is_offline (data))
magic_type = identify_by_magic (data, md);
/* If GNOME-VFS doesn't recognize the data by magic, but it
* contains English words, it will call it text/plain. If the
* filename-based check came up with something different, use
* that instead.
*/
if (magic_type && name_type && !strcmp (magic_type, "text/plain"))
return g_strdup (name_type);
/* If the MIME part data was online, and the magic check
* returned something, use that, since it's more reliable.
*/
if (magic_type)
return g_strdup (magic_type);
/* Otherwise try guessing based on the filename */
if (name_type)
return g_strdup (name_type);
/* Another possibility to try is the x-mac-type / x-mac-creator
* parameter to Content-Type used by some Mac email clients. That
* would require a Mac type to mime type conversion table.
*/
/* If the data part is offline, then we didn't try magic
* before, so force it to be loaded so we can try again later.
* FIXME: In a perfect world, we would not load the content
* just to identify the MIME type.
*/
if (camel_data_wrapper_is_offline (data))
mail_content_loaded (data, md);
return NULL;
}
static const char *
identify_by_magic (CamelDataWrapper *data, MailDisplay *md)
{
GnomeVFSMimeSniffBuffer *sniffer;
CamelStream *memstream;
const char *type;
GByteArray *ba;
ba = g_byte_array_new ();
memstream = camel_stream_mem_new_with_byte_array (ba);
camel_data_wrapper_write_to_stream (data, memstream);
if (ba->len) {
sniffer = gnome_vfs_mime_sniff_buffer_new_from_memory (ba->data, ba->len);
type = gnome_vfs_get_mime_type_for_buffer (sniffer);
gnome_vfs_mime_sniff_buffer_free (sniffer);
} else
type = NULL;
camel_object_unref (CAMEL_OBJECT (memstream));
return type;
}
