Squashed 'external/toxcore/c-toxcore/' changes from c9cdae001..9ed2fa80d

9ed2fa80d fix(toxav): remove extra copy of video frame on encode
de30cf3ad docs: Add new file kinds, that should be useful to all clients.
d5b5e879d fix(DHT): Correct node skipping logic timed out nodes.
30e71fe97 refactor: Generate event dispatch functions and add tox_events_dispatch.
8fdbb0b50 style: Format parameter lists in event handlers.
d00dee12b refactor: Add warning logs when losing chat invites.
b144e8db1 feat: Add a way to look up a file number by ID.
849281ea0 feat: Add a way to fetch groups by chat ID.
a2c177396 refactor: Harden event system and improve type safety.
8f5caa656 refactor: Add MessagePack string support to bin_pack.
34e8d5ad5 chore: Add GitHub CodeQL workflow and local Docker runner.
f7b068010 refactor: Add nullability annotations to event headers.
788abe651 refactor(toxav): Use system allocator for mutexes.
2e4b423eb refactor: Use specific typedefs for public API arrays.
2baf34775 docs(toxav): update idle iteration interval see 679444751876fa3882a717772918ebdc8f083354
2f87ac67b feat: Add Event Loop abstraction (Ev).
f8dfc38d8 test: Fix data race in ToxScenario virtual_clock.
38313921e test(TCP): Add regression test for TCP priority queue integrity.
f94a50d9a refactor(toxav): Replace mutable_mutex with dynamically allocated mutex.
ad054511e refactor: Internalize DHT structs and add debug helpers.
8b467cc96 fix: Prevent potential integer overflow in group chat handshake.
4962bdbb8 test: Improve TCP simulation and add tests
5f0227093 refactor: Allow nullable data in group chat handlers.
e97b18ea9 chore: Improve Windows Docker support.
b14943bbd refactor: Move Logger out of Messenger into Tox.
dd3136250 cleanup: Apply nullability qualifiers to C++ codebase.
1849f70fc refactor: Extract low-level networking code to net and os_network.
8fec75421 refactor: Delete tox_random, align on rng and os_random.
a03ae8051 refactor: Delete tox_memory, align on mem and os_memory.
4c88fed2c refactor: Use `std::` prefixes more consistently in C++ code.
72452f2ae test: Add some more tests for onion and shared key cache.
d5a51b09a cleanup: Use tox_attributes.h in tox_private.h and install it.
b6f5b9fc5 test: Add some benchmarks for various high level things.
8a8d02785 test(support): Introduce threaded Tox runner and simulation barrier
d68d1d095 perf(toxav): optimize audio and video intermediate buffers by keeping them around
REVERT: c9cdae001 fix(toxav): remove extra copy of video frame on encode

git-subtree-dir: external/toxcore/c-toxcore
git-subtree-split: 9ed2fa80d582c714d6bdde6a7648220a92cddff8

testing/support/doubles/fake_network_udp_test.cc

@@ -0,0 +1,75 @@
+#include <gtest/gtest.h>
+
+#include "fake_network_stack.hh"
+#include "network_universe.hh"
+
+#ifdef _WIN32
+#define WIN32_LEAN_AND_MEAN
+#define NOMINMAX
+#include <winsock2.h>
+#else
+#include <netinet/in.h>
+#include <sys/socket.h>
+#endif
+
+namespace tox::test {
+namespace {
+
+    class FakeNetworkUdpTest : public ::testing::Test {
+    public:
+        FakeNetworkUdpTest()
+            : ip1(make_ip(0x0A000001))  // 10.0.0.1
+            , ip2(make_ip(0x0A000002))  // 10.0.0.2
+            , stack1{universe, ip1}
+            , stack2{universe, ip2}
+        {
+        }
+
+    protected:
+        NetworkUniverse universe;
+        IP ip1, ip2;
+        FakeNetworkStack stack1;
+        FakeNetworkStack stack2;
+    };
+
+    TEST_F(FakeNetworkUdpTest, UdpExchange)
+    {
+        Socket sock1 = stack1.socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+        Socket sock2 = stack2.socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+
+        IP_Port addr1;
+        addr1.ip = ip1;
+        addr1.port = net_htons(1234);
+        ASSERT_EQ(stack1.bind(sock1, &addr1), 0);
+
+        IP_Port addr2;
+        addr2.ip = ip2;
+        addr2.port = net_htons(5678);
+        ASSERT_EQ(stack2.bind(sock2, &addr2), 0);
+
+        const char *msg = "Hello UDP";
+        size_t msg_len = strlen(msg) + 1;
+
+        // Send from 1 to 2
+        ASSERT_EQ(stack1.sendto(sock1, reinterpret_cast<const uint8_t *>(msg), msg_len, &addr2),
+            static_cast<int>(msg_len));
+
+        // Delivery
+        universe.process_events(10);  // With some time offset
+
+        // Receive at 2
+        uint8_t buffer[1024];
+        IP_Port from_addr;
+        int recv_len = stack2.recvfrom(sock2, buffer, sizeof(buffer), &from_addr);
+
+        ASSERT_EQ(recv_len, static_cast<int>(msg_len));
+        EXPECT_STREQ(reinterpret_cast<const char *>(buffer), msg);
+        EXPECT_EQ(net_ntohl(from_addr.ip.ip.v4.uint32), net_ntohl(ip1.ip.v4.uint32));
+        EXPECT_EQ(net_ntohs(from_addr.port), 1234);
+
+        stack1.close(sock1);
+        stack2.close(sock2);
+    }
+
+}  // namespace
+}  // namespace tox::test