Hooks: central vtable install with restore support

Move vtable patching into hooks.cpp: one call clones the table, validates every
slot, records the originals and installs the clone. Installs happen from the
setup, game and paint threads, so the bookkeeping is mutex-protected.

Client, CInput, IVModelRender, IStudioRender and ISurface all use it, and
hooks_restore_all() can now put every interface back (previously impossible).

1 files changed, 22 insertions, 22 deletions

diff --git a/src/studio.cpp b/src/studio.cpp
index 8b0a710..275bfba 100644
--- a/src/studio.cpp
+++ b/src/studio.cpp
@@ -597,15 +597,17 @@ void chams_init() {
          (void *)g_force_override, (void *)g_orig_model_exec);
     return;
   }
-  void **nvt = vtable_clone(g_iface.modelrender, 32);
-  if (!nvt) {
-    logf("chams: vtable clone failed");
+  VtablePatch patches[] = {
+      {1, (void *)&hkdForceOverride,
+       reinterpret_cast<void **>(&g_real_force_override)}, // track forced passes
+      {19, (void *)&hkdModelExecute,
+       reinterpret_cast<void **>(&g_orig_model_exec)},
+  };
+  if (!hooks_install_vtable(g_iface.modelrender, 32, patches, 2)) {
+    logf("chams: vtable patch failed");
     return;
   }
-  nvt[1] = (void *)&hkdForceOverride; // track engine-forced passes
-  nvt[19] = (void *)&hkdModelExecute;
   g_modelrender = g_iface.modelrender;
-  *(void ***)g_modelrender = nvt;
   logf("chams: IVModelRender %p hooked (draw=%p override=%p)", g_modelrender,
        (void *)g_orig_model_exec, (void *)g_force_override);
 }
@@ -641,24 +643,22 @@ void studio_props_init() {
     logf("studio: interface has no vtable");
     return;
   }
-  void **vt = vtable_clone(sr, 49);
-  if (!vt) {
-    logf("studio: vtable clone failed");
+  VtablePatch patches[] = {
+      {27, (void *)&hook_set_color,
+       reinterpret_cast<void **>(&g_orig_set_color)},
+      {28, (void *)&hook_set_alpha,
+       reinterpret_cast<void **>(&g_orig_set_alpha)},
+      {29, (void *)&hook_draw_model,
+       reinterpret_cast<void **>(&g_orig_draw_model)},
+      {30, (void *)&hook_draw_static_prop,
+       reinterpret_cast<void **>(&g_orig_draw_static)},
+      {46, (void *)&hook_draw_array,
+       reinterpret_cast<void **>(&g_orig_draw_array)},
+  };
+  if (!hooks_install_vtable(sr, 49, patches, 5)) {
+    logf("studio: vtable patch failed");
     return;
   }
-
-  g_orig_set_color = (SetColorFn)vt[27];
-  g_orig_set_alpha = (SetAlphaFn)vt[28];
-  g_orig_draw_model = (DrawModelFn)vt[29];
-  g_orig_draw_static = (DrawStaticFn)vt[30];
-  g_orig_draw_array = (DrawArrayFn)vt[46];
-  vt[27] = (void *)&hook_set_color;
-  vt[28] = (void *)&hook_set_alpha;
-  vt[29] = (void *)&hook_draw_model;
-  vt[30] = (void *)&hook_draw_static_prop;
-  vt[46] = (void *)&hook_draw_array;
-
-  *(void ***)sr = vt;
   g_installed = true;
   logf("studio: IStudioRender %p hooked (color=%p draw=%p static=%p "
        "array=%p)", sr, (void *)g_orig_set_color, (void *)g_orig_draw_model,