wsutil/feature_list.h

   1 /** @file
   2  * Declarations of routines for gathering and handling lists of
   3  * present/absent features (usually actually dependencies)
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #ifndef __WSUTIL_FEATURE_LIST_H__
  13 #define __WSUTIL_FEATURE_LIST_H__
  14
  15 #include <glib.h>
  16 #include "ws_symbol_export.h"
  17
  18 #ifdef __cplusplus
  19 extern "C" {
  20 #endif /* __cplusplus */
  21
  22 /*
  23  * Handle to a list of features/dependencies.
  24  * Semi-opaque. Functions which gather the list of features
  25  * will be passed one of these to use with
  26  * `with_feature()`/`without_feature()` (below).
  27  */
  28 typedef GList **feature_list;
  29
  30 /*
  31  * The format of entries in a feature_list is a char* starting with a
  32  * '+' or '-' character indicating if the feature is respectively
  33  * present or absent, followed by the unchanged feature description.
  34  * This allows the insert order of features to be preserved,
  35  * while still preserving the present/absent status in a simple way.
  36  */
  37
  38
  39 /*
  40  * Pointer to a function which gathers a list of features.
  41  */
  42 typedef void(*gather_feature_func)(feature_list l);
  43
  44 /*
  45  * Add an indicator to the given feature_list that the named
  46  * feature is present.
  47  */
  48 WS_DLL_PUBLIC
  49 void with_feature(feature_list l, const char *fmt, ...) G_GNUC_PRINTF(2,3);
  50
  51 /*
  52  * Add an indicator to the given feature_list that the named
  53  * feature is absent.
  54  */
  55 WS_DLL_PUBLIC
  56 void without_feature(feature_list l, const char *fmt, ...) G_GNUC_PRINTF(2,3);
  57
  58 /*
  59  * Sort the given feature list, alphabetically by feature name.
  60  * (The leading '+' or '-' is not factored into the sort.)
  61  * Currently unused.
  62  */
  63 WS_DLL_PUBLIC
  64 void sort_features(feature_list l);
  65
  66 /*
  67  * Free the memory used by the feature list,
  68  * and reset its pointer to NULL.
  69  */
  70 WS_DLL_PUBLIC
  71 void free_features(feature_list l);
  72
  73 #ifdef __cplusplus
  74 }
  75 #endif /* __cplusplus */
  76
  77 #endif /* __WSUTIL_FEATURE_LIST_H__ */