1 files changed, 83 insertions, 84 deletions

diff --git a/fallback.c b/fallback.c
index 385a1495..0516919c 100644
--- a/fallback.c
+++ b/fallback.c
@@ -3,7 +3,7 @@
 ** TecCGraf - PUC-Rio
 */
  
-char *rcs_fallback="$Id: fallback.c,v 1.28 1997/03/19 19:41:10 roberto Exp roberto $";
+char *rcs_fallback="$Id: fallback.c,v 1.29 1997/03/19 21:12:34 roberto Exp roberto $";
 
 #include <stdio.h>
 #include <string.h>
@@ -18,6 +18,19 @@ char *rcs_fallback="$Id: fallback.c,v 1.28 1997/03/19 19:41:10 roberto Exp rober
 #include "hash.h"
 
 
+static char *typenames[] = { /* ORDER LUA_T */
+  "userdata", "line", "cmark", "mark", "function",
+  "function", "table", "string", "number", "nil",
+  NULL
+};
+
+
+void luaI_type (void)
+{
+  lua_Object o = lua_getparam(1);
+  lua_pushstring(typenames[-ttype(luaI_Address(o))]);
+  lua_pushnumber(lua_tag(o));
+}
 
 
 /* -------------------------------------------
@@ -94,27 +107,19 @@ void luaI_invalidaterefs (void)
 * Internal Methods 
 */
 
-char *eventname[] = {
-  "gettable",  /* IM_GETTABLE */
-  "arith",  /* IM_ARITH */
-  "order",  /* IM_ORDER */
-  "concat",  /* IM_CONCAT */
-  "settable",  /* IM_SETTABLE */
-  "gc",  /* IM_GC */
-  "function",  /* IM_FUNCTION */
-  "index",  /* IM_INDEX */
+char *luaI_eventname[] = {  /* ORDER IM */
+  "gettable", "settable", "index", "add", "sub", "mul", "div",
+  "pow", "unm", "lt", "le", "gt", "ge", "concat", "gc", "function",
   NULL
 };
 
 
-char *geventname[] = {
-  "error",  /* GIM_ERROR */
-  "getglobal",  /* GIM_GETGLOBAL */
-  "setglobal",  /* GIM_SETGLOBAL */
+static char *geventname[] = {  /* ORDER GIM */
+  "error", "getglobal", "setglobal",
   NULL
 };
 
-static int luaI_findevent (char *name, char *list[])
+static int findstring (char *name, char *list[])
 {
   int i;
   for (i=0; list[i]; i++)
@@ -126,7 +131,7 @@ static int luaI_findevent (char *name, char *list[])
 
 static int luaI_checkevent (char *name, char *list[])
 {
-  int e = luaI_findevent(name, list);
+  int e = findstring(name, list);
   if (e < 0)
     lua_error("invalid event name");
   return e;
@@ -141,38 +146,25 @@ static struct IM {
 static int IMtable_size = 0;
 static int last_tag = LUA_T_NIL;
 
-static struct {
-  lua_Type t;
-  int event;
-} exceptions[] = {  /* list of events that cannot be modified */
-    {LUA_T_NUMBER, IM_ARITH},
-    {LUA_T_NUMBER, IM_ORDER},
-    {LUA_T_NUMBER, IM_GC},
-    {LUA_T_STRING, IM_ARITH},
-    {LUA_T_STRING, IM_ORDER},
-    {LUA_T_STRING, IM_CONCAT},
-    {LUA_T_STRING, IM_GC},
-    {LUA_T_ARRAY, IM_GETTABLE},
-    {LUA_T_ARRAY, IM_SETTABLE},
-    {LUA_T_FUNCTION, IM_FUNCTION},
-    {LUA_T_FUNCTION, IM_GC},
-    {LUA_T_CFUNCTION, IM_FUNCTION},
-    {LUA_T_CFUNCTION, IM_GC},
-    {LUA_T_NIL, 0}  /* flag end of list */
+static char validevents[NUM_TYPES][IM_N] = { /* ORDER LUA_T, ORDER IM */
+{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},  /* LUA_T_USERDATA */
+{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},  /* LUA_T_LINE */
+{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},  /* LUA_T_CMARK */
+{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},  /* LUA_T_MARK */
+{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0},  /* LUA_T_CFUNCTION */
+{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0},  /* LUA_T_FUNCTION */
+{0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},  /* LUA_T_ARRAY */
+{1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},  /* LUA_T_STRING */
+{1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1},  /* LUA_T_NUMBER */
+{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0}   /* LUA_T_NIL */
 };
 
-
-static int validevent (int t, int event)
+static int validevent (lua_Type t, int e)
 {
-  int i;
-  if (t == LUA_T_NIL)  /* cannot modify any event for nil */
-    return 0;
-  for (i=0; exceptions[i].t != LUA_T_NIL; i++)
-    if (exceptions[i].t == t && exceptions[i].event == event)
-      return 0;
-  return 1;
+  return (t < LUA_T_NIL) ?  1 : validevents[-t][e];
 }
 
+
 static void init_entry (int tag)
 {
   int i;
@@ -193,14 +185,14 @@ void luaI_initfallbacks (void)
 
 int lua_newtag (char *t)
 {
+  int tp;
   --last_tag;
   if ((-last_tag) >= IMtable_size)
     IMtable_size = growvector(&luaI_IMtable, IMtable_size,
                               struct IM, memEM, MAX_INT);
-  if (strcmp(t, "table") == 0)
-    luaI_IMtable[-last_tag].tp = LUA_T_ARRAY;
-  else if (strcmp(t, "userdata") == 0)
-    luaI_IMtable[-last_tag].tp = LUA_T_USERDATA;
+  tp = -findstring(t, typenames);
+  if (tp == LUA_T_ARRAY || tp == LUA_T_USERDATA)
+    luaI_IMtable[-last_tag].tp = tp;
   else
     lua_error("invalid type for new tag");
   init_entry(last_tag);
@@ -246,14 +238,14 @@ int luaI_tag (Object *o)
   else return t;
 }
 
-Object *luaI_getim (int tag, int event)
+Object *luaI_getim (int tag, IMS event)
 {
   if (tag > LUA_T_USERDATA)
     tag = LUA_T_USERDATA;  /* default for non-registered tags */
   return &luaI_IMtable[-tag].int_method[event];
 }
 
-Object *luaI_getimbyObj (Object *o, int event)
+Object *luaI_getimbyObj (Object *o, IMS event)
 {
   return luaI_getim(luaI_tag(o), event);
 }
@@ -261,13 +253,13 @@ Object *luaI_getimbyObj (Object *o, int event)
 void luaI_setintmethod (void)
 {
   int t = (int)luaL_check_number(1, "setintmethod");
-  int e = luaI_checkevent(luaL_check_string(2, "setintmethod"), eventname);
+  int e = luaI_checkevent(luaL_check_string(2, "setintmethod"), luaI_eventname);
   lua_Object func = lua_getparam(3);
+  checktag(t);
   if (!validevent(t, e))
     lua_error("cannot change this internal method");
   luaL_arg_check(lua_isnil(func) || lua_isfunction(func), "setintmethod",
                  3, "function expected");
-  checktag(t);
   luaI_pushobject(&luaI_IMtable[-t].int_method[e]);
   luaI_IMtable[-t].int_method[e] = *luaI_Address(func);
 }
@@ -276,7 +268,7 @@ static Object gmethod[GIM_N] = {
   {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}
 };
 
-Object *luaI_getgim (int event)
+Object *luaI_getgim (IMGS event)
 {
   return &gmethod[event];
 }
@@ -326,47 +318,54 @@ static void typeFB (void)
 }
 
 
+static void fillvalids (IMS e, Object *func)
+{
+  int t;
+  for (t=LUA_T_NIL; t<=LUA_T_USERDATA; t++)
+    if (validevent(t, e))
+      luaI_IMtable[-t].int_method[e] = *func;
+}
+
 void luaI_setfallback (void)
 {
   int e;
+  Object oldfunc;
+  lua_CFunction replace;
   char *name = luaL_check_string(1, "setfallback");
   lua_Object func = lua_getparam(2);
   luaL_arg_check(lua_isfunction(func), "setfallback", 2, "function expected");
-  e = luaI_findevent(name, geventname);
+  e = findstring(name, geventname);
   if (e >= 0) {  /* global event */
-    switch (e) {
-      case GIM_ERROR:
-        gmethod[e] = *luaI_Address(func);
-        lua_pushcfunction(errorFB);
-        break;
-      case GIM_GETGLOBAL:  /* goes through */
-      case GIM_SETGLOBAL:
-        gmethod[e] = *luaI_Address(func);
-        lua_pushcfunction(nilFB);
-        break;
-      default: lua_error("internal error");
-    }
+    oldfunc = gmethod[e];
+    gmethod[e] = *luaI_Address(func);
+    replace = (e == GIM_ERROR) ? errorFB : nilFB;
   }
-  else {  /* tagged name? */
-    int t;
-    Object oldfunc;
-    e = luaI_checkevent(name, eventname);
+  else if ((e = findstring(name, luaI_eventname)) >= 0) {
     oldfunc = luaI_IMtable[LUA_T_USERDATA].int_method[e];
-    for (t=LUA_T_NIL; t<=LUA_T_USERDATA; t++)
-      if (validevent(t, e))
-        luaI_IMtable[-t].int_method[e] = *luaI_Address(func);
-    if (oldfunc.ttype != LUA_T_NIL)
-      luaI_pushobject(&oldfunc);
-    else {
-      switch (e) {
-       case IM_GC:  case IM_INDEX:
-         lua_pushcfunction(nilFB);
-         break;
-       default:
-         lua_pushcfunction(typeFB);
-         break;
-      }
-    }
+    fillvalids(e, luaI_Address(func));
+    replace = (e == IM_GC || e == IM_INDEX) ? nilFB : typeFB;
   }
+  else if (strcmp(name, "arith") == 0) {  /* old arith fallback */
+    int i;
+    oldfunc = luaI_IMtable[LUA_T_USERDATA].int_method[IM_ADD];
+    for (i=IM_ADD; i<=IM_UNM; i++)  /* ORDER IM */
+      fillvalids(i, luaI_Address(func));
+    replace = typeFB;
+  }
+  else if (strcmp(name, "order") == 0) {  /* old order fallback */
+    int i;
+    oldfunc = luaI_IMtable[LUA_T_USERDATA].int_method[IM_LT];
+    for (i=IM_LT; i<=IM_GE; i++)  /* ORDER IM */
+      fillvalids(i, luaI_Address(func));
+    replace = typeFB;
+  }
+  else {
+    lua_error("invalid fallback name");
+    replace = NULL;  /* to avoid warnings */
+  }
+  if (oldfunc.ttype != LUA_T_NIL)
+    luaI_pushobject(&oldfunc);
+  else
+    lua_pushcfunction(replace);
 }