Modify PUC Lua to wrap C++ exceptions (#12445)

5 files changed, 24 insertions, 1 deletions

diff --git a/lib/lua/src/lapi.c b/lib/lua/src/lapi.c
index 5d5145d2e..383e65d60 100644
--- a/lib/lua/src/lapi.c
+++ b/lib/lua/src/lapi.c
@@ -137,6 +137,18 @@ LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
 }
 
 
+/* MINETEST-SPECIFIC CHANGE */
+LUA_API lua_CFunctionwrapper lua_atccall (lua_State *L,
+                                          lua_CFunctionwrapper wrapf) {
+  lua_CFunctionwrapper old;
+  lua_lock(L);
+  old = G(L)->wrapcf;
+  G(L)->wrapcf = wrapf;
+  lua_unlock(L);
+  return old;
+}
+
+
 LUA_API lua_State *lua_newthread (lua_State *L) {
   lua_State *L1;
   lua_lock(L);
diff --git a/lib/lua/src/ldo.c b/lib/lua/src/ldo.c
index d1bf786cb..57d2ac7c2 100644
--- a/lib/lua/src/ldo.c
+++ b/lib/lua/src/ldo.c
@@ -317,7 +317,11 @@ int luaD_precall (lua_State *L, StkId func, int nresults) {
     if (L->hookmask & LUA_MASKCALL)
       luaD_callhook(L, LUA_HOOKCALL, -1);
     lua_unlock(L);
-    n = (*curr_func(L)->c.f)(L);  /* do the actual call */
+    /* MINETEST-SPECIFIC CHANGE: Let custom code wrap C function calls. */
+    if (G(L)->wrapcf)
+      n = G(L)->wrapcf(L, *curr_func(L)->c.f);
+    else
+      n = (*curr_func(L)->c.f)(L);
     lua_lock(L);
     if (n < 0)  /* yielding? */
       return PCRYIELD;
diff --git a/lib/lua/src/lstate.c b/lib/lua/src/lstate.c
index 4313b83a0..eced4a585 100644
--- a/lib/lua/src/lstate.c
+++ b/lib/lua/src/lstate.c
@@ -166,6 +166,7 @@ LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
   setnilvalue(registry(L));
   luaZ_initbuffer(L, &g->buff);
   g->panic = NULL;
+  g->wrapcf = NULL; /* MINETEST-SPECIFIC CHANGE */
   g->gcstate = GCSpause;
   g->rootgc = obj2gco(L);
   g->sweepstrgc = 0;
diff --git a/lib/lua/src/lstate.h b/lib/lua/src/lstate.h
index 3bc575b6b..c4364ea3f 100644
--- a/lib/lua/src/lstate.h
+++ b/lib/lua/src/lstate.h
@@ -86,6 +86,7 @@ typedef struct global_State {
   int gcpause;  /* size of pause between successive GCs */
   int gcstepmul;  /* GC `granularity' */
   lua_CFunction panic;  /* to be called in unprotected errors */
+  lua_CFunctionwrapper wrapcf; /* MINETEST-SPECIFIC CHANGE */
   TValue l_registry;
   struct lua_State *mainthread;
   UpVal uvhead;  /* head of double-linked list of all open upvalues */
diff --git a/lib/lua/src/lua.h b/lib/lua/src/lua.h
index a4b73e743..1d7fe927f 100644
--- a/lib/lua/src/lua.h
+++ b/lib/lua/src/lua.h
@@ -113,6 +113,11 @@ LUA_API lua_State *(lua_newthread) (lua_State *L);
 
 LUA_API lua_CFunction (lua_atpanic) (lua_State *L, lua_CFunction panicf);
 
+/* MINETEST-SPECIFIC CHANGE: Let custom code wrap C function calls. */
+typedef int (*lua_CFunctionwrapper)(lua_State *L, lua_CFunction f);
+LUA_API lua_CFunctionwrapper (lua_atccall) (lua_State *L,
+                                            lua_CFunctionwrapper wrapf);
+
 
 /*
 ** basic stack manipulation