qbsp: fix memory/.bsp file corruption if map contains a texture name longer than 31 characters

qbsp/writebsp.cc

@@ -80,7 +80,19 @@ size_t ExportMapTexinfo(size_t texinfonum)
     dest.flags = src.flags;
     dest.miptex = src.miptex;
     dest.vecs = src.vecs;
-    strcpy(dest.texture.data(), map.texinfoTextureName(texinfonum).c_str());
+
+    const std::string &src_name = map.texinfoTextureName(texinfonum);
+    if (src_name.size() > (dest.texture.size() - 1)) {
+        logging::print("WARNING: texture name '{}' exceeds maximum length {} and will be truncated\n",
+            src_name, dest.texture.size() - 1);
+    }
+    for (size_t i = 0; i < (dest.texture.size() - 1); ++i) {
+        if (i < src_name.size())
+            dest.texture[i] = src_name[i];
+        else
+            dest.texture[i] = '\0';
+    }
+    dest.texture[dest.texture.size() - 1] = '\0';
     dest.value = map.miptex[src.miptex].value;
 
     src.outputnum = i;

testmaps/q2_long_texture_name.map

@@ -0,0 +1,22 @@
+// Game: Quake 2
+// Format: Quake2
+// entity 0
+{
+"classname" "worldspawn"
+"_tb_mod" "q2_wal_metadata"
+"_tb_textures" "textures/long_folder_name_test"
+// brush 0
+{
+( -64 -64 -16 ) ( -64 -63 -16 ) ( -64 -64 -15 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+( -64 -64 -16 ) ( -64 -64 -15 ) ( -63 -64 -16 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+( -64 -64 -16 ) ( -63 -64 -16 ) ( -64 -63 -16 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+( 64 64 16 ) ( 64 65 16 ) ( 65 64 16 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+( 64 64 16 ) ( 65 64 16 ) ( 64 64 17 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+( 64 64 16 ) ( 64 64 17 ) ( 64 65 16 ) long_folder_name_test/long_texture_name_test 0 0 0 1 1
+}
+}
+// entity 1
+{
+"classname" "info_player_start"
+"origin" "-32 0 40"
+}

tests/test_qbsp_q2.cc

@@ -268,9 +268,25 @@ TEST_CASE("nodraw_light" * doctest::test_suite("testmaps_q2"))
     CHECK(texinfo->flags.native == (Q2_SURF_LIGHT | Q2_SURF_NODRAW));
 }
 
-TEST_CASE("nodraw_detail_light" * doctest::test_suite("testmaps_q2"))
+TEST_CASE("q2_long_texture_name" * doctest::test_suite("testmaps_q2"))
 {
-    const auto [bsp, bspx, prt] = LoadTestmapQ2("q2_nodraw_detail_light.map", {"-includeskip"});
+    const auto [bsp, bspx, prt] = LoadTestmapQ2("q2_long_texture_name.map");
+
+    CHECK(GAME_QUAKE_II == bsp.loadversion->game->id);
+
+    auto *topface = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[0], {0, 0, 16}, {0, 0, 1});
+    REQUIRE(nullptr != topface);
+
+    // this won't work in game, but we're mostly checking for lack of memory corruption
+    // (a warning is issued)
+    auto *texinfo = Face_Texinfo(&bsp, topface);
+    CHECK(std::string(texinfo->texture.data()) == "long_folder_name_test/long_text");
+    CHECK(texinfo->nexttexinfo == -1);
+}
+
+TEST_CASE("nodraw_light" * doctest::test_suite("testmaps_q2"))
+{
+    const auto [bsp, bspx, prt] = LoadTestmapQ2("q2_nodraw_light.map", {"-includeskip"});
 
     CHECK(GAME_QUAKE_II == bsp.loadversion->game->id);