glib/gio/gcontenttype.c

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/* GIO - GLib Input, Output and Streaming Library
*
* Copyright (C) 2006-2007 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Alexander Larsson <alexl@redhat.com>
*/
#include <config.h>
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include "gcontenttypeprivate.h"
#include "glibintl.h"
#include "gioalias.h"
/**
* SECTION:gcontenttype
* @short_description: Platform-specific content typing
*
* A content type is a platform specific string that defines the type
* of a file. On unix it is a mime type, on win32 it is an extension string
* like ".doc", ".txt" or a percieved string like "audio". Such strings
* can be looked up in the registry at HKEY_CLASSES_ROOT.
**/
#ifdef G_OS_WIN32
#include <windows.h>
static char *
get_registry_classes_key (const char *subdir,
const wchar_t *key_name)
{
wchar_t *wc_key;
HKEY reg_key = NULL;
DWORD key_type;
DWORD nbytes;
char *value_utf8;
value_utf8 = NULL;
nbytes = 0;
wc_key = g_utf8_to_utf16 (subdir, -1, NULL, NULL, NULL);
if (RegOpenKeyExW (HKEY_CLASSES_ROOT, wc_key, 0,
KEY_QUERY_VALUE, &reg_key) == ERROR_SUCCESS &&
RegQueryValueExW (reg_key, key_name, 0,
&key_type, NULL, &nbytes) == ERROR_SUCCESS &&
key_type == REG_SZ)
{
wchar_t *wc_temp = g_new (wchar_t, (nbytes+1)/2 + 1);
RegQueryValueExW (reg_key, key_name, 0,
&key_type, (LPBYTE) wc_temp, &nbytes);
wc_temp[nbytes/2] = '\0';
value_utf8 = g_utf16_to_utf8 (wc_temp, -1, NULL, NULL, NULL);
g_free (wc_temp);
}
g_free (wc_key);
if (reg_key != NULL)
RegCloseKey (reg_key);
return value_utf8;
}
gboolean
g_content_type_equals (const char *type1,
const char *type2)
{
char *progid1, *progid2;
gboolean res;
g_return_val_if_fail (type1 != NULL, FALSE);
g_return_val_if_fail (type2 != NULL, FALSE);
if (g_ascii_strcasecmp (type1, type2) == 0)
return TRUE;
res = FALSE;
progid1 = get_registry_classes_key (type1, NULL);
progid2 = get_registry_classes_key (type2, NULL);
if (progid1 != NULL && progid2 != NULL &&
strcmp (progid1, progid2) == 0)
res = TRUE;
g_free (progid1);
g_free (progid2);
return res;
}
gboolean
g_content_type_is_a (const char *type,
const char *supertype)
{
gboolean res;
char *value_utf8;
g_return_val_if_fail (type != NULL, FALSE);
g_return_val_if_fail (supertype != NULL, FALSE);
if (g_content_type_equals (type, supertype))
return TRUE;
res = FALSE;
value_utf8 = get_registry_classes_key (type, L"PerceivedType");
if (value_utf8 && strcmp (value_utf8, supertype) == 0)
res = TRUE;
g_free (value_utf8);
return res;
}
gboolean
g_content_type_is_unknown (const char *type)
{
g_return_val_if_fail (type != NULL, FALSE);
return strcmp ("*", type) == 0;
}
char *
g_content_type_get_description (const char *type)
{
char *progid;
char *description;
g_return_val_if_fail (type != NULL, NULL);
progid = get_registry_classes_key (type, NULL);
if (progid)
{
description = get_registry_classes_key (progid, NULL);
g_free (progid);
if (description)
return description;
}
if (g_content_type_is_unknown (type))
return g_strdup (_("Unknown type"));
return g_strdup_printf (_("%s filetype"), type);
}
char *
g_content_type_get_mime_type (const char *type)
{
char *mime;
g_return_val_if_fail (type != NULL, NULL);
mime = get_registry_classes_key (type, L"Content Type");
if (mime)
return mime;
else if (g_content_type_is_unknown (type))
return g_strdup ("application/octet-stream");
else if (*type == '.')
return g_strdup_printf ("application/x-ext-%s", type+1);
/* TODO: Map "image" to "image/ *", etc? */
return g_strdup ("application/octet-stream");
}
GIcon *
g_content_type_get_icon (const char *type)
{
g_return_val_if_fail (type != NULL, NULL);
/* TODO: How do we represent icons???
In the registry they are the default value of
HKEY_CLASSES_ROOT\<progid>\DefaultIcon with typical values like:
<type>: <value>
REG_EXPAND_SZ: %SystemRoot%\System32\Wscript.exe,3
REG_SZ: shimgvw.dll,3
*/
return NULL;
}
gboolean
g_content_type_can_be_executable (const char *type)
{
g_return_val_if_fail (type != NULL, FALSE);
if (strcmp (type, ".exe") == 0 ||
strcmp (type, ".com") == 0 ||
strcmp (type, ".bat") == 0)
return TRUE;
return FALSE;
}
static gboolean
looks_like_text (const guchar *data,
gsize data_size)
{
gsize i;
guchar c;
for (i = 0; i < data_size; i++)
{
c = data[i];
if (g_ascii_iscntrl (c) && !g_ascii_isspace (c))
return FALSE;
}
return TRUE;
}
char *
g_content_type_guess (const char *filename,
const guchar *data,
gsize data_size,
gboolean *result_uncertain)
{
char *basename;
char *type;
char *dot;
type = NULL;
if (filename)
{
basename = g_path_get_basename (filename);
dot = strrchr (basename, '.');
if (dot)
type = g_strdup (dot);
g_free (basename);
}
if (type)
return type;
if (data && looks_like_text (data, data_size))
return g_strdup (".txt");
return g_strdup ("*");
}
GList *
g_content_types_get_registered (void)
{
DWORD index;
wchar_t keyname[256];
DWORD key_len;
char *key_utf8;
GList *types;
types = NULL;
index = 0;
key_len = 256;
while (RegEnumKeyExW(HKEY_CLASSES_ROOT,
index,
keyname,
&key_len,
NULL,
NULL,
NULL,
NULL) == ERROR_SUCCESS)
{
key_utf8 = g_utf16_to_utf8 (keyname, -1, NULL, NULL, NULL);
if (key_utf8)
{
if (*key_utf8 == '.')
types = g_list_prepend (types, key_utf8);
else
g_free (key_utf8);
}
index++;
key_len = 256;
}
return g_list_reverse (types);
}
#else /* !G_OS_WIN32 - Unix specific version */
#include <dirent.h>
#define XDG_PREFIX _gio_xdg
#include "xdgmime/xdgmime.h"
/* We lock this mutex whenever we modify global state in this module. */
G_LOCK_DEFINE_STATIC (gio_xdgmime);
gsize
_g_unix_content_type_get_sniff_len (void)
{
gsize size;
G_LOCK (gio_xdgmime);
size = xdg_mime_get_max_buffer_extents ();
G_UNLOCK (gio_xdgmime);
return size;
}
char *
_g_unix_content_type_unalias (const char *type)
{
char *res;
G_LOCK (gio_xdgmime);
res = g_strdup (xdg_mime_unalias_mime_type (type));
G_UNLOCK (gio_xdgmime);
return res;
}
char **
_g_unix_content_type_get_parents (const char *type)
{
const char *umime;
const char **parents;
GPtrArray *array;
int i;
array = g_ptr_array_new ();
G_LOCK (gio_xdgmime);
umime = xdg_mime_unalias_mime_type (type);
g_ptr_array_add (array, g_strdup (umime));
parents = xdg_mime_get_mime_parents (umime);
for (i = 0; parents && parents[i] != NULL; i++)
g_ptr_array_add (array, g_strdup (parents[i]));
G_UNLOCK (gio_xdgmime);
g_ptr_array_add (array, NULL);
return (char **)g_ptr_array_free (array, FALSE);
}
/**
* g_content_type_equals:
* @type1: a content type string.
* @type2: a content type string.
*
* Compares two content types for equality.
*
* Returns: %TRUE if the two strings are identical or equivalent,
* %FALSE otherwise.
**/
gboolean
g_content_type_equals (const char *type1,
const char *type2)
{
gboolean res;
g_return_val_if_fail (type1 != NULL, FALSE);
g_return_val_if_fail (type2 != NULL, FALSE);
G_LOCK (gio_xdgmime);
res = xdg_mime_mime_type_equal (type1, type2);
G_UNLOCK (gio_xdgmime);
return res;
}
/**
* g_content_type_is_a:
* @type: a content type string.
* @supertype: a string.
*
* Determines if @type is a subset of @supertype.
*
* Returns: %TRUE if @type is a kind of @supertype,
* %FALSE otherwise.
**/
gboolean
g_content_type_is_a (const char *type,
const char *supertype)
{
gboolean res;
g_return_val_if_fail (type != NULL, FALSE);
g_return_val_if_fail (supertype != NULL, FALSE);
G_LOCK (gio_xdgmime);
res = xdg_mime_mime_type_subclass (type, supertype);
G_UNLOCK (gio_xdgmime);
return res;
}
/**
* g_content_type_is_unknown:
* @type: a content type string.
*
* Checks if the content type is known by GIO.
*
* Returns: %TRUE if the type is unknown.
**/
gboolean
g_content_type_is_unknown (const char *type)
{
g_return_val_if_fail (type != NULL, FALSE);
return strcmp (XDG_MIME_TYPE_UNKNOWN, type) == 0;
}
typedef enum {
MIME_TAG_TYPE_OTHER,
MIME_TAG_TYPE_COMMENT
} MimeTagType;
typedef struct {
int current_type;
int current_lang_level;
int comment_lang_level;
char *comment;
} MimeParser;
static int
language_level (const char *lang)
{
const char * const *lang_list;
int i;
/* The returned list is sorted from most desirable to least
desirable and always contains the default locale "C". */
lang_list = g_get_language_names ();
for (i = 0; lang_list[i]; i++)
if (strcmp (lang_list[i], lang) == 0)
return 1000-i;
return 0;
}
static void
mime_info_start_element (GMarkupParseContext *context,
const gchar *element_name,
const gchar **attribute_names,
const gchar **attribute_values,
gpointer user_data,
GError **error)
{
int i;
const char *lang;
MimeParser *parser = user_data;
if (strcmp (element_name, "comment") == 0)
{
lang = "C";
for (i = 0; attribute_names[i]; i++)
if (strcmp (attribute_names[i], "xml:lang") == 0)
{
lang = attribute_values[i];
break;
}
parser->current_lang_level = language_level (lang);
parser->current_type = MIME_TAG_TYPE_COMMENT;
}
else
parser->current_type = MIME_TAG_TYPE_OTHER;
}
static void
mime_info_end_element (GMarkupParseContext *context,
const gchar *element_name,
gpointer user_data,
GError **error)
{
MimeParser *parser = user_data;
parser->current_type = MIME_TAG_TYPE_OTHER;
}
static void
mime_info_text (GMarkupParseContext *context,
const gchar *text,
gsize text_len,
gpointer user_data,
GError **error)
{
MimeParser *parser = user_data;
if (parser->current_type == MIME_TAG_TYPE_COMMENT &&
parser->current_lang_level > parser->comment_lang_level)
{
g_free (parser->comment);
parser->comment = g_strndup (text, text_len);
parser->comment_lang_level = parser->current_lang_level;
}
}
static char *
load_comment_for_mime_helper (const char *dir,
const char *basename)
{
GMarkupParseContext *context;
char *filename, *data;
gsize len;
gboolean res;
MimeParser parse_data = {0};
GMarkupParser parser = {
mime_info_start_element,
mime_info_end_element,
mime_info_text
};
filename = g_build_filename (dir, "mime", basename, NULL);
res = g_file_get_contents (filename, &data, &len, NULL);
g_free (filename);
if (!res)
return NULL;
context = g_markup_parse_context_new (&parser, 0, &parse_data, NULL);
res = g_markup_parse_context_parse (context, data, len, NULL);
g_free (data);
g_markup_parse_context_free (context);
if (!res)
return NULL;
return parse_data.comment;
}
static char *
load_comment_for_mime (const char *mimetype)
{
const char * const* dirs;
char *basename;
char *comment;
int i;
basename = g_strdup_printf ("%s.xml", mimetype);
comment = load_comment_for_mime_helper (g_get_user_data_dir (), basename);
if (comment)
{
g_free (basename);
return comment;
}
dirs = g_get_system_data_dirs ();
for (i = 0; dirs[i] != NULL; i++)
{
comment = load_comment_for_mime_helper (dirs[i], basename);
if (comment)
{
g_free (basename);
return comment;
}
}
g_free (basename);
return g_strdup_printf (_("%s type"), mimetype);
}
/**
* g_content_type_get_description:
* @type: a content type string.
*
* Gets the human readable description of the content type.
*
* Returns: a short description of the content type @type.
**/
char *
g_content_type_get_description (const char *type)
{
static GHashTable *type_comment_cache = NULL;
char *comment;
g_return_val_if_fail (type != NULL, NULL);
G_LOCK (gio_xdgmime);
if (type_comment_cache == NULL)
type_comment_cache = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
comment = g_hash_table_lookup (type_comment_cache, type);
comment = g_strdup (comment);
G_UNLOCK (gio_xdgmime);
if (comment != NULL)
return comment;
comment = load_comment_for_mime (type);
G_LOCK (gio_xdgmime);
g_hash_table_insert (type_comment_cache,
g_strdup (type),
g_strdup (comment));
G_UNLOCK (gio_xdgmime);
return comment;
}
/**
* g_content_type_get_mime_type:
* @type: a content type string.
*
* Gets the mime-type for the content type.
*
* Returns: the registered mime-type for the given @type.
**/
char *
g_content_type_get_mime_type (const char *type)
{
g_return_val_if_fail (type != NULL, NULL);
return g_strdup (type);
}
/**
* g_content_type_get_icon:
* @type: a content type string.
*
* Gets the icon for a content type.
*
* Returns: #GIcon corresponding to the content type.
**/
GIcon *
g_content_type_get_icon (const char *type)
{
g_return_val_if_fail (type != NULL, NULL);
/* TODO: Implement */
return NULL;
}
/**
* g_content_type_can_be_executable:
* @type: a content type string.
*
* Checks if a content type can be executable. Note that for instance
* things like text files can be executables (i.e. scripts and batch files).
*
* Returns: %TRUE if the file type corresponds to a type that
* can be executable, %FALSE otherwise.
**/
gboolean
g_content_type_can_be_executable (const char *type)
{
g_return_val_if_fail (type != NULL, FALSE);
if (g_content_type_is_a (type, "application/x-executable") ||
g_content_type_is_a (type, "text/plain"))
return TRUE;
return FALSE;
}
static gboolean
looks_like_text (const guchar *data, gsize data_size)
{
gsize i;
for (i = 0; i < data_size; i++)
{
if g_ascii_iscntrl (data[i])
return FALSE;
}
return TRUE;
}
/**
* g_content_type_guess:
* @filename: a string.
* @data: a stream of data.
* @data_size: the size of @data.
* @result_uncertain: a flag indicating the certainty of the
* result.
*
* Guesses the content type based on example data. If the function is
* uncertain, @result_uncertain will be set to %TRUE.
*
* Returns: a string indicating a guessed content type for the
* given data.
**/
char *
g_content_type_guess (const char *filename,
const guchar *data,
gsize data_size,
gboolean *result_uncertain)
{
char *basename;
const char *name_mimetypes[10], *sniffed_mimetype;
char *mimetype;
int i;
int n_name_mimetypes;
int sniffed_prio;
sniffed_prio = 0;
n_name_mimetypes = 0;
sniffed_mimetype = XDG_MIME_TYPE_UNKNOWN;
if (result_uncertain)
*result_uncertain = FALSE;
G_LOCK (gio_xdgmime);
if (filename)
{
basename = g_path_get_basename (filename);
n_name_mimetypes = xdg_mime_get_mime_types_from_file_name (basename, name_mimetypes, 10);
g_free (basename);
}
/* Got an extension match, and no conflicts. This is it. */
if (n_name_mimetypes == 1)
{
G_UNLOCK (gio_xdgmime);
return g_strdup (name_mimetypes[0]);
}
if (data)
{
sniffed_mimetype = xdg_mime_get_mime_type_for_data (data, data_size, &sniffed_prio);
if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
data &&
looks_like_text (data, data_size))
sniffed_mimetype = "text/plain";
}
if (n_name_mimetypes == 0)
{
if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
result_uncertain)
*result_uncertain = TRUE;
mimetype = g_strdup (sniffed_mimetype);
}
else
{
mimetype = NULL;
if (sniffed_mimetype != XDG_MIME_TYPE_UNKNOWN)
{
if (sniffed_prio >= 80) /* High priority sniffing match, use that */
mimetype = g_strdup (sniffed_mimetype);
else
{
/* There are conflicts between the name matches and we have a sniffed
type, use that as a tie breaker. */
for (i = 0; i < n_name_mimetypes; i++)
{
if ( xdg_mime_mime_type_subclass (name_mimetypes[i], sniffed_mimetype))
{
/* This nametype match is derived from (or the same as) the sniffed type).
This is probably it. */
mimetype = g_strdup (name_mimetypes[i]);
break;
}
}
}
}
if (mimetype == NULL)
{
/* Conflicts, and sniffed type was no help or not there. guess on the first one */
mimetype = g_strdup (name_mimetypes[0]);
if (result_uncertain)
*result_uncertain = TRUE;
}
}
G_UNLOCK (gio_xdgmime);
return mimetype;
}
static gboolean
foreach_mimetype (gpointer key,
gpointer value,
gpointer user_data)
{
GList **l = user_data;
*l = g_list_prepend (*l, (char *)key);
return TRUE;
}
static void
enumerate_mimetypes_subdir (const char *dir,
const char *prefix,
GHashTable *mimetypes)
{
DIR *d;
struct dirent *ent;
char *mimetype;
d = opendir (dir);
if (d)
{
while ((ent = readdir (d)) != NULL)
{
if (g_str_has_suffix (ent->d_name, ".xml"))
{
mimetype = g_strdup_printf ("%s/%.*s", prefix, (int) strlen (ent->d_name) - 4, ent->d_name);
g_hash_table_insert (mimetypes, mimetype, NULL);
}
}
closedir (d);
}
}
static void
enumerate_mimetypes_dir (const char *dir,
GHashTable *mimetypes)
{
DIR *d;
struct dirent *ent;
char *mimedir;
char *name;
mimedir = g_build_filename (dir, "mime", NULL);
d = opendir (mimedir);
if (d)
{
while ((ent = readdir (d)) != NULL)
{
if (strcmp (ent->d_name, "packages") != 0)
{
name = g_build_filename (mimedir, ent->d_name, NULL);
if (g_file_test (name, G_FILE_TEST_IS_DIR))
enumerate_mimetypes_subdir (name, ent->d_name, mimetypes);
g_free (name);
}
}
closedir (d);
}
g_free (mimedir);
}
/**
* g_content_types_get_registered:
*
* Gets a list of strings containing the registered content types on
* the system.
*
* Returns: #GList of the registered content types.
**/
GList *
g_content_types_get_registered (void)
{
const char * const* dirs;
GHashTable *mimetypes;
int i;
GList *l;
mimetypes = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
enumerate_mimetypes_dir (g_get_user_data_dir (), mimetypes);
dirs = g_get_system_data_dirs ();
for (i = 0; dirs[i] != NULL; i++)
enumerate_mimetypes_dir (dirs[i], mimetypes);
l = NULL;
g_hash_table_foreach_steal (mimetypes, foreach_mimetype, &l);
g_hash_table_destroy (mimetypes);
return l;
}
#endif /* Unix version */
#define __G_CONTENT_TYPE_C__
#include "gioaliasdef.c"