From 4b91e9cde630573cb35bb20101eb74cf5cf79a27 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Tue, 16 Sep 1997 16:25:59 -0300 Subject: Tag methods --- ltm.c | 317 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 317 insertions(+) create mode 100644 ltm.c (limited to 'ltm.c') diff --git a/ltm.c b/ltm.c new file mode 100644 index 00000000..215c7bf5 --- /dev/null +++ b/ltm.c @@ -0,0 +1,317 @@ +/* +** $Id: $ +** Tag methods +** See Copyright Notice in lua.h +*/ + + +#include +#include + +#include "lauxlib.h" +#include "ldo.h" +#include "lmem.h" +#include "lobject.h" +#include "ltm.h" + +static struct IM init_IM[NUM_TYPES] = { +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}, +{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, + {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}} +}; + + + + +char *luaT_eventname[] = { /* ORDER IM */ + "gettable", "settable", "index", "getglobal", "setglobal", "add", + "sub", "mul", "div", "pow", "unm", "lt", "le", "gt", "ge", + "concat", "gc", "function", + NULL +}; + + +static int luaI_checkevent (char *name, char *list[]) +{ + int e = luaO_findstring(name, list); + if (e < 0) + luaL_verror("`%.50s' is not a valid event name", name); + return e; +} + + +struct IM *luaT_IMtable = init_IM; + +static int IMtable_size = NUM_TYPES; + +static int last_tag = -(NUM_TYPES-1); + + +/* events in LUA_T_LINE are all allowed, since this is used as a +* 'placeholder' for "default" fallbacks +*/ +static char validevents[NUM_TYPES][IM_N] = { /* ORDER LUA_T, ORDER IM */ +{1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1}, /* LUA_T_USERDATA */ +{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, /* LUA_T_LINE */ +{0, 0, 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, 0, 0}, /* LUA_T_MARK */ +{1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0}, /* LUA_T_CFUNCTION */ +{1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0}, /* LUA_T_FUNCTION */ +{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* LUA_T_PROTO */ +{0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, /* LUA_T_ARRAY */ +{1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}, /* LUA_T_STRING */ +{1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1}, /* LUA_T_NUMBER */ +{1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1} /* LUA_T_NIL */ +}; + +static int validevent (lua_Type t, int e) +{ /* ORDER LUA_T */ + return (t < LUA_T_NIL) ? 1 : validevents[-t][e]; +} + + +static void init_entry (int tag) +{ + int i; + for (i=0; i= IMtable_size) { + if (luaT_IMtable == init_IM) { /* fist time? */ + IMtable_size *= 2; + luaT_IMtable = luaM_newvector(IMtable_size, struct IM); + memcpy(luaT_IMtable, init_IM, sizeof(init_IM)); + } + else + IMtable_size = luaM_growvector(&luaT_IMtable, IMtable_size, + struct IM, memEM, MAX_INT); + } + init_entry(last_tag); + return last_tag; +} + + +static void checktag (int tag) +{ /* ORDER LUA_T */ + if (!(last_tag <= tag && tag <= 0)) + luaL_verror("%d is not a valid tag", tag); +} + +void luaT_realtag (int tag) +{ + if (!(last_tag <= tag && tag < LUA_T_NIL)) + luaL_verror("tag %d is not result of `newtag'", tag); +} + + + +int luaT_efectivetag (TObject *o) +{ + lua_Type t = ttype(o); + if (t == LUA_T_USERDATA) { + int tag = o->value.ts->tag; + return (tag >= 0) ? LUA_T_USERDATA : tag; + } + else if (t == LUA_T_ARRAY) + return o->value.a->htag; + else return t; +} + + +TObject *luaT_gettagmethod (int t, char *event) +{ + int e = luaI_checkevent(event, luaT_eventname); + checktag(t); + if (validevent(t, e)) + return luaT_getim(t,e); + else + return luaT_getim(LUA_T_CMARK, IM_GETTABLE); /* always nil */ +} + + +void luaT_settagmethod (int t, char *event, TObject *func) +{ + TObject temp = *func; + int e = luaI_checkevent(event, luaT_eventname); + checktag(t); + if (!validevent(t, e)) + luaL_verror("settagmethod: cannot change internal method `%s' for tag %d", + luaT_eventname[e], t); + *func = *luaT_getim(t,e); + *luaT_getim(t, e) = temp; +} + + +char *luaT_travtagmethods (int (*fn)(TObject *)) +{ + int e; + if (fn(&luaD_errorim)) + return "error"; + for (e=IM_GETTABLE; e<=IM_FUNCTION; e++) { /* ORDER IM */ + int t; + for (t=0; t>=last_tag; t--) + if (fn(luaT_getim(t,e))) + return luaT_eventname[e]; + } + return NULL; +} + + +/* +* =================================================================== +* compatibility with old fallback system +*/ +#if LUA_COMPAT2_5 + +#include "lapi.h" + +static void errorFB (void) +{ + lua_Object o = lua_getparam(1); + if (lua_isstring(o)) + fprintf(stderr, "lua: %s\n", lua_getstring(o)); + else + fprintf(stderr, "lua: unknown error\n"); +} + + +static void nilFB (void) { } + + +static void typeFB (void) +{ + lua_error("unexpected type"); +} + + +static void fillvalids (IMS e, TObject *func) +{ + int t; + for (t=LUA_T_NIL; t<=LUA_T_USERDATA; t++) + if (validevent(t, e)) + *luaT_getim(t, e) = *func; +} + + +void luaT_setfallback (void) +{ + static char *oldnames [] = {"error", "getglobal", "arith", "order", NULL}; + TObject oldfunc; + lua_CFunction replace; + char *name = luaL_check_string(1); + lua_Object func = lua_getparam(2); + luaL_arg_check(lua_isfunction(func), 2, "function expected"); + switch (luaO_findstring(name, oldnames)) { + case 0: /* old error fallback */ + oldfunc = luaD_errorim; + luaD_errorim = *luaA_Address(func); + replace = errorFB; + break; + case 1: /* old getglobal fallback */ + oldfunc = *luaT_getim(LUA_T_NIL, IM_GETGLOBAL); + *luaT_getim(LUA_T_NIL, IM_GETGLOBAL) = *luaA_Address(func); + replace = nilFB; + break; + case 2: { /* old arith fallback */ + int i; + oldfunc = *luaT_getim(LUA_T_NUMBER, IM_POW); + for (i=IM_ADD; i<=IM_UNM; i++) /* ORDER IM */ + fillvalids(i, luaA_Address(func)); + replace = typeFB; + break; + } + case 3: { /* old order fallback */ + int i; + oldfunc = *luaT_getim(LUA_T_LINE, IM_LT); + for (i=IM_LT; i<=IM_GE; i++) /* ORDER IM */ + fillvalids(i, luaA_Address(func)); + replace = typeFB; + break; + } + default: { + int e; + if ((e = luaO_findstring(name, luaT_eventname)) >= 0) { + oldfunc = *luaT_getim(LUA_T_LINE, e); + fillvalids(e, luaA_Address(func)); + replace = (e == IM_GC || e == IM_INDEX) ? nilFB : typeFB; + } + else { + luaL_verror("`%.50s' is not a valid fallback name", name); + replace = NULL; /* to avoid warnings */ + } + } + } + if (oldfunc.ttype != LUA_T_NIL) + luaA_pushobject(&oldfunc); + else + lua_pushcfunction(replace); +} +#endif + -- cgit v1.2.3-55-g6feb