cleanup: Add a TOX_HIDE_DEPRECATED check to hide deprecated symbols.

Compiling with that flag will make tox compile roughly as if it were
v0.3.0.

auto_tests/save_compatibility_test.c

@@ -71,22 +71,22 @@ static uint8_t *read_save(const char *save_path, size_t *length)
 
 static void test_save_compatibility(const char *save_path)
 {
-    struct Tox_Options options = {0};
-    tox_options_default(&options);
+    Tox_Options *options = tox_options_new(nullptr);
+    ck_assert(options != nullptr);
 
     size_t size = 0;
     uint8_t *save_data = read_save(save_path, &size);
     ck_assert_msg(save_data != nullptr, "error while reading save file '%s'", save_path);
 
-    options.savedata_data = save_data;
-    options.savedata_length = size;
-    options.savedata_type = TOX_SAVEDATA_TYPE_TOX_SAVE;
+    tox_options_set_savedata_type(options, TOX_SAVEDATA_TYPE_TOX_SAVE);
+    tox_options_set_savedata_data(options, save_data, size);
 
     size_t index = 0;
     Tox_Err_New err;
-    Tox *tox = tox_new_log(&options, &err, &index);
+    Tox *tox = tox_new_log(options, &err, &index);
     ck_assert_msg(tox, "failed to create tox, error number: %d", err);
 
+    tox_options_free(options);
     free(save_data);
 
     const size_t name_size = tox_self_get_name_size(tox);

toxcore/tox.c

@@ -10,6 +10,7 @@
 #define _XOPEN_SOURCE 600
 #endif /* _XOPEN_SOURCE */
 
+#undef TOX_HIDE_DEPRECATED
 #include "tox.h"
 
 #include <assert.h>
@@ -33,7 +34,7 @@
 #include "onion_client.h"
 #include "state.h"
 #include "tox_private.h"
-#include "tox_struct.h"
+#include "tox_struct.h" // IWYU pragma: keep
 #include "util.h"
 
 #include "../toxencryptsave/defines.h"

toxcore/tox.h

@@ -87,6 +87,13 @@
  * If any other thread calls tox_self_set_name while this thread is allocating
  * memory, the length may have become invalid, and the call to
  * tox_self_get_name may cause undefined behaviour.
+ *
+ * @section deprecations
+ *
+ * Some functions and types are deprecated. We recommend compiling with
+ * `-DTOX_HIDE_DEPRECATED` to hide them. They will be removed in the next major
+ * version of Tox (and since we're in major version 0, that means the next
+ * minor version).
  */
 #ifndef C_TOXCORE_TOXCORE_TOX_H
 #define C_TOXCORE_TOXCORE_TOX_H
@@ -512,6 +519,7 @@ typedef void tox_log_cb(Tox *tox, Tox_Log_Level level, const char *file, uint32_
  *   private) in v0.3.0.
  */
 typedef struct Tox_Options Tox_Options;
+#ifndef TOX_HIDE_DEPRECATED
 struct Tox_Options {
 
     /**
@@ -687,6 +695,7 @@ struct Tox_Options {
      */
     bool experimental_disable_dns;
 };
+#endif /* TOX_HIDE_DEPRECATED */
 
 bool tox_options_get_ipv6_enabled(const Tox_Options *options);
 
@@ -3165,6 +3174,7 @@ const char *tox_err_conference_by_id_to_string(Tox_Err_Conference_By_Id value);
 Tox_Conference_Number tox_conference_by_id(
     const Tox *tox, const uint8_t id[TOX_CONFERENCE_ID_SIZE], Tox_Err_Conference_By_Id *error);
 
+#ifndef TOX_HIDE_DEPRECATED
 /**
  * @brief Get the conference unique ID.
  *
@@ -3179,6 +3189,7 @@ Tox_Conference_Number tox_conference_by_id(
  */
 bool tox_conference_get_uid(
     const Tox *tox, Tox_Conference_Number conference_number, uint8_t uid[TOX_CONFERENCE_UID_SIZE]);
+#endif /* TOX_HIDE_DEPRECATED */
 
 typedef enum Tox_Err_Conference_By_Uid {
 
@@ -3201,6 +3212,7 @@ typedef enum Tox_Err_Conference_By_Uid {
 
 const char *tox_err_conference_by_uid_to_string(Tox_Err_Conference_By_Uid value);
 
+#ifndef TOX_HIDE_DEPRECATED
 /**
  * @brief Return the conference number associated with the specified uid.
  *
@@ -3213,6 +3225,7 @@ const char *tox_err_conference_by_uid_to_string(Tox_Err_Conference_By_Uid value)
  */
 Tox_Conference_Number tox_conference_by_uid(
     const Tox *tox, const uint8_t uid[TOX_CONFERENCE_UID_SIZE], Tox_Err_Conference_By_Uid *error);
+#endif /* TOX_HIDE_DEPRECATED */
 
 /** @} */
 
@@ -3820,6 +3833,7 @@ typedef enum Tox_Err_Group_Reconnect {
 
 const char *tox_err_group_reconnect_to_string(Tox_Err_Group_Reconnect value);
 
+#ifndef TOX_HIDE_DEPRECATED
 /**
  * Reconnects to a group.
  *
@@ -3834,6 +3848,7 @@ const char *tox_err_group_reconnect_to_string(Tox_Err_Group_Reconnect value);
  * @deprecated Use `tox_group_join` instead.
  */
 bool tox_group_reconnect(Tox *tox, Tox_Group_Number group_number, Tox_Err_Group_Reconnect *error);
+#endif /* TOX_HIDE_DEPRECATED */
 
 typedef enum Tox_Err_Group_Leave {
 
@@ -5747,6 +5762,7 @@ void tox_callback_group_moderation(Tox *tox, tox_group_moderation_cb *callback);
 //!TOKSTYLE-
 #ifndef DOXYGEN_IGNORE
 
+#ifndef TOX_HIDE_DEPRECATED
 typedef Tox_Err_Options_New TOX_ERR_OPTIONS_NEW;
 typedef Tox_Err_New TOX_ERR_NEW;
 typedef Tox_Err_Bootstrap TOX_ERR_BOOTSTRAP;
@@ -5786,6 +5802,7 @@ typedef Tox_Connection TOX_CONNECTION;
 typedef Tox_File_Control TOX_FILE_CONTROL;
 typedef Tox_Conference_Type TOX_CONFERENCE_TYPE;
 typedef enum Tox_File_Kind TOX_FILE_KIND;
+#endif /* TOX_HIDE_DEPRECATED */
 
 #endif
 //!TOKSTYLE+

toxcore/tox_api.c

@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-3.0-or-later
  * Copyright © 2016-2021 The TokTok team.
  */
+#undef TOX_HIDE_DEPRECATED
 #include "tox.h"
 
 #include <stdlib.h>