Added a bit more protected and intelligent lua code there.

2 files changed, 57 insertions, 17 deletions

diff --git a/include/BLua.h b/include/BLua.h
index d5e4f2b..0a7b7a6 100644
--- a/include/BLua.h
+++ b/include/BLua.h
@@ -17,7 +17,7 @@
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-/* $Id: BLua.h,v 1.22 2004-12-17 11:46:41 pixel Exp $ */
+/* $Id: BLua.h,v 1.23 2004-12-27 18:50:55 pixel Exp $ */
 
 #ifndef __BLUA_H__
 #define __BLUA_H__
@@ -55,7 +55,7 @@ class Lua : public Base {
     void open_dir();
     void declarefunc(const String &, lua_CFunction, int = LUA_GLOBALSINDEX);
     void call(const String &, int = LUA_GLOBALSINDEX, int = 0, int = 0);
-    void call(int = 0, int = 0);
+    void call(int = 0, int = 0) throw (GeneralException);
     void push();
     void push(lua_Number);
     void push(const String &);
@@ -70,6 +70,7 @@ class Lua : public Base {
     void gettable(int = -2, bool raw = false);
     void setvar();
     int gettop();
+    void push_lua_context();
     void error(const String &);
     int type(int = -1);
     bool isnil(int = -1);
@@ -103,10 +104,13 @@ class Lua : public Base {
     
     virtual void lock() {}
     virtual void unlock() {}
+
+    bool is_protected();
   private:
       Lua(lua_State *);
     lua_State * L;
     static std::map<lua_State *, Lua *> lualist;
+    bool _protected;
 };
 
 class LuaObject : public Base {
diff --git a/lib/BLua.cc b/lib/BLua.cc
index 5ec58e1..335da3d 100644
--- a/lib/BLua.cc
+++ b/lib/BLua.cc
@@ -17,7 +17,7 @@
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-/* $Id: BLua.cc,v 1.25 2004-12-22 00:08:01 pixel Exp $ */
+/* $Id: BLua.cc,v 1.26 2004-12-27 18:50:55 pixel Exp $ */
 
 #include "BLua.h"
 #include <lualib.h>
@@ -26,8 +26,6 @@
 #define BUFFERSIZE	  2048
 #endif
 
-
-
 extern "C" {
     void do_lua_lock(lua_State * _L) {
 	Lua * L;
@@ -56,6 +54,7 @@ class LuaStatics : public Base {
     static int putF(lua_State *, const void *, size_t, void *);
     static int luapanic(lua_State *);
     static int trueluapanic(lua_State *) throw(GeneralException);
+    static int luaerror(lua_State *);
     static int collector(lua_State *);
     static int destructor(lua_State *);
 
@@ -70,13 +69,24 @@ class LuaStatics : public Base {
 
 std::map<lua_State *, Lua *> Lua::lualist;
 
+int LuaStatics::luaerror(lua_State * _L) throw (GeneralException) {
+    Lua * L = Lua::find(_L);
+    L->push_lua_context();
+    L->showerror();
+    return 0;
+}
+
 int LuaStatics::luapanic(lua_State * L) {
     return trueluapanic(L);
 }
 
-int LuaStatics::trueluapanic(lua_State * L) throw (GeneralException) {
-    Lua::find(L)->showerror();
-    throw LuaException("Error running Lua code, bailing out.");
+int LuaStatics::trueluapanic(lua_State * _L) throw (GeneralException) {
+    Lua * L = Lua::find(_L);
+    if (L->is_protected())
+        return 0;  // luaerror will get it for us...
+    L->push_lua_context();
+    L->showerror();
+    throw LuaException("Unprotected error running Lua code, bailing out; except unstable lua environment.");
 }
 
 int LuaStatics::andB(lua_State * _L) {
@@ -218,7 +228,7 @@ Lua::Lua() : L(lua_open()) {
     declarefunc("hex", LuaStatics::hex);
 }
 
-Lua::Lua(lua_State * _L) : L(_L) {
+Lua::Lua(lua_State * _L) : L(_L), _protected(false) {
     lua_atpanic(L, LuaStatics::luapanic);
     lualist[L] = this;
 }
@@ -228,6 +238,10 @@ Lua::~Lua() {
     lua_close(L);
 }
 
+bool Lua::is_protected() {
+    return _protected;
+}
+
 Lua::Lua(const Lua & l) throw (GeneralException) {
     throw GeneralException("Error: can't duplicate a Lua object.");
 }
@@ -277,11 +291,31 @@ void Lua::call(const String & f, int i, int nargs, int nresults) {
     lua_pushstring(L, f.to_charp());
     lua_gettable(L, i);
     lua_insert(L, -1 - nargs - nresults);
-    lua_call(L, nargs, nresults);
-}
-
-void Lua::call(int nargs, int nresults) {
-    lua_call(L, nargs, nresults);
+    call(nargs, nresults);
+}
+
+void Lua::call(int nargs, int nresults) throw(GeneralException) {
+    int r;
+
+    lua_pushcfunction(L, LuaStatics::luaerror);
+    lua_insert(L, 1);
+    _protected = true;
+    r = lua_pcall(L, nargs, nresults, 1);
+    _protected = false;
+    lua_remove(L, 1);
+
+    switch(r) {
+    case 0:
+        return;
+    case LUA_ERRRUN:
+        throw LuaException("Runtime error while running LUA code.");
+    case LUA_ERRMEM:
+        throw LuaException("Memory allocation error while running LUA code.");
+    case LUA_ERRERR:
+        throw LuaException("Error in Error function.");
+    default:
+        throw LuaException("Unknow error while running LUA code.");
+    }
 }
 
 void Lua::push() {
@@ -352,7 +386,7 @@ int Lua::gettop() {
     return lua_gettop(L);
 }
 
-void Lua::error(const String & msg) {
+void Lua::push_lua_context() {
     String whole_msg;
     struct lua_Debug ar;
     bool got_error = false;
@@ -370,7 +404,9 @@ void Lua::error(const String & msg) {
         }
         level++;
     } while (!got_error);
+}
 
+void Lua::error(const String & msg) {
     push(msg);
 
     lua_error(L);
@@ -488,6 +524,7 @@ void Lua::load(Handle * h, bool docall) throw (GeneralException) {
     status = lua_load(L, LuaStatics::getF, &lf, h->GetName().to_charp());
 
     if (status) {
+        push_lua_context();
 	showerror();
 	throw LuaException("Error loading lua chunk from Handle `" + h->GetName() + "'");
     }
@@ -533,8 +570,7 @@ void Lua::showerror() {
     int i;
     String t;
 
-    printm(M_ERROR, "Lua object: Got an LUA error\n");
-    printm(M_ERROR, "Inspecting LUA stack\n");
+    printm(M_ERROR, "Lua object: Got an LUA error, inspecting stack.\n");
 
     if (n == 0) {
 	printm(M_ERROR, "Stack empty\n");