Squashed 'external/toxcore/c-toxcore/' changes from 1828c5356..c9cdae001

c9cdae001 fix(toxav): remove extra copy of video frame on encode
4f6d4546b test: Improve the fake network library.
a2581e700 refactor(toxcore): generate `Friend_Request` and `Dht_Nodes_Response`
2aaa11770 refactor(toxcore): use Tox_Memory in generated events
5c367452b test(toxcore): fix incorrect mutex in tox_scenario_get_time
8f92e710f perf: Add a timed limit of number of cookie requests.
695b6417a test: Add some more simulated network support.
815ae9ce9 test(toxcore): fix thread-safety in scenario framework
6d85c754e test(toxcore): add unit tests for net_crypto
9c22e79cc test(support): add SimulatedEnvironment for deterministic testing
f34fcb195 chore: Update windows Dockerfile to debian stable (trixie).
ece0e8980 fix(group_moderation): allow validating unsorted sanction list signatures
a4fa754d7 refactor: rename struct Packet to struct Net_Packet
d6f330f85 cleanup: Fix some warnings from coverity.
e206bffa2 fix(group_chats): fix sync packets reverting topics
0e4715598 test: Add new scenario testing framework.
668291f44 refactor(toxcore): decouple Network_Funcs from sockaddr via IP_Port
fc4396cef fix: potential division by zero in toxav and unsafe hex parsing
8e8b352ab refactor: Add nullable annotations to struct members.
7740bb421 refactor: decouple net_crypto from DHT
1936d4296 test: add benchmark for toxav audio and video
46bfdc2df fix: correct printf format specifiers for unsigned integers
REVERT: 1828c5356 fix(toxav): remove extra copy of video frame on encode

git-subtree-dir: external/toxcore/c-toxcore
git-subtree-split: c9cdae001341e701fca980c9bb9febfeb95d2902

testing/support/public/tox_network.hh

@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later
+ * Copyright © 2026 The TokTok team.
+ */
+
+#ifndef C_TOXCORE_TESTING_SUPPORT_TOX_NETWORK_H
+#define C_TOXCORE_TESTING_SUPPORT_TOX_NETWORK_H
+
+#include <vector>
+
+#include "simulation.hh"
+
+namespace tox::test {
+
+struct ConnectedFriend {
+    std::unique_ptr<SimulatedNode> node;
+    SimulatedNode::ToxPtr tox;
+    uint32_t friend_number;
+
+    ConnectedFriend(std::unique_ptr<SimulatedNode> node_in, SimulatedNode::ToxPtr tox_in,
+        uint32_t friend_number_in)
+        : node(std::move(node_in))
+        , tox(std::move(tox_in))
+        , friend_number(friend_number_in)
+    {
+    }
+
+    ConnectedFriend(ConnectedFriend &&) = default;
+    ConnectedFriend &operator=(ConnectedFriend &&) = default;
+    ~ConnectedFriend();
+};
+
+/**
+ * @brief Sets up a network of connected Tox instances.
+ *
+ * This function creates num_friends Tox instances, adds them as friends to main_tox,
+ * and bootstraps them to main_node. It then runs the simulation until all friends
+ * are connected to main_tox.
+ *
+ * @param sim The simulation to run.
+ * @param main_tox The main Tox instance to which friends will connect.
+ * @param main_node The simulated node hosting the main Tox instance.
+ * @param num_friends The number of friends to create and connect.
+ * @param options Optional Tox_Options to use for the friend Tox instances.
+ * @return A vector of ConnectedFriend structures, each representing a friend.
+ */
+std::vector<ConnectedFriend> setup_connected_friends(Simulation &sim, Tox *main_tox,
+    SimulatedNode &main_node, int num_friends, const Tox_Options *options = nullptr);
+
+/**
+ * @brief Connects two existing Tox instances as friends.
+ *
+ * This function adds each Tox instance as a friend to the other, bootstraps
+ * them to each other, and runs the simulation until they are connected.
+ *
+ * @param sim The simulation to run.
+ * @param node1 The simulated node hosting the first Tox instance.
+ * @param tox1 The first Tox instance.
+ * @param node2 The simulated node hosting the second Tox instance.
+ * @param tox2 The second Tox instance.
+ * @return True if connected successfully, false otherwise.
+ */
+bool connect_friends(
+    Simulation &sim, SimulatedNode &node1, Tox *tox1, SimulatedNode &node2, Tox *tox2);
+
+/**
+ * @brief Sets up a group and has all friends join it.
+ *
+ * This function creates a new public group on main_tox, invites all friends in the
+ * provided vector, and runs the simulation until all friends have joined and
+ * main_tox sees all of them.
+ *
+ * @param sim The simulation to run.
+ * @param main_tox The main Tox instance that creates the group.
+ * @param friends The friends to invite to the group.
+ * @return The group number on the main Tox instance, or UINT32_MAX on failure.
+ */
+uint32_t setup_connected_group(
+    Simulation &sim, Tox *main_tox, const std::vector<ConnectedFriend> &friends);
+
+}  // namespace tox::test
+
+#endif  // C_TOXCORE_TESTING_SUPPORT_TOX_NETWORK_H