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/*
This file is part of libextractor.
Copyright (C) 2012 Vidyut Samanta and Christian Grothoff
libextractor 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 3, or (at your
option) any later version.
libextractor 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 libextractor; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
/**
* @file plugins/mime_extractor.c
* @brief plugin to determine mime types using libmagic (from 'file')
* @author Christian Grothoff
*/
#include "platform.h"
#include "extractor.h"
#include <magic.h>
/**
* Global handle to MAGIC data.
*/
static magic_t magic;
/**
* Path we used for loading magic data, NULL is used for 'default'.
*/
static char *magic_path;
/**
* Main entry method for the 'application/ogg' extraction plugin. The
* 'config' of the context can be used to specify an alternative magic
* path. If config is not given, the default magic path will be
* used.
*
* @param ec extraction context provided to the plugin
*/
void
EXTRACTOR_mime_extract_method (struct EXTRACTOR_ExtractContext *ec)
{
void *buf;
ssize_t ret;
const char *mime;
ret = ec->read (ec->cls,
&buf,
16 * 1024);
if (-1 == ret)
return;
if ( ( (NULL == magic_path) &&
(NULL != ec->config) ) ||
( (NULL != magic_path) &&
(NULL == ec->config) ) ||
( (NULL != magic_path) &&
(NULL != ec->config) &&
(0 != strcmp (magic_path,
ec->config) )) )
{
if (NULL != magic_path)
free (magic_path);
magic_close (magic);
magic = magic_open (MAGIC_MIME_TYPE);
if (0 != magic_load (magic, ec->config))
{
/* FIXME: report errors? */
}
if (NULL != ec->config)
magic_path = strdup (ec->config);
else
magic_path = NULL;
}
if (NULL == (mime = magic_buffer (magic, buf, ret)))
return;
ec->proc (ec->cls,
"mime",
EXTRACTOR_METATYPE_MIMETYPE,
EXTRACTOR_METAFORMAT_UTF8,
"text/plain",
mime,
strlen (mime) + 1);
}
/**
* Constructor for the library. Loads the magic file.
*/
void __attribute__ ((constructor))
mime_ltdl_init ()
{
magic = magic_open (MAGIC_MIME_TYPE);
if (0 != magic_load (magic, magic_path))
{
/* FIXME: how to deal with errors? */
}
}
/**
* Destructor for the library, cleans up.
*/
void __attribute__ ((destructor))
mime_ltdl_fini ()
{
if (NULL != magic)
{
magic_close (magic);
magic = NULL;
}
if (NULL != magic_path)
{
free (magic_path);
magic_path = NULL;
}
}
/* end of mime_extractor.c */
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