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authorRoberto Ierusalimschy <roberto@inf.puc-rio.br>1997-09-16 16:25:59 -0300
committerRoberto Ierusalimschy <roberto@inf.puc-rio.br>1997-09-16 16:25:59 -0300
commit4b91e9cde630573cb35bb20101eb74cf5cf79a27 (patch)
treea3f4021ffcff5856633dfac5f1f3faa38e4ab0bf /ltm.c
parent26c5f56ad1ac6f0409e638f44af75da09f2b0a0b (diff)
downloadlua-4b91e9cde630573cb35bb20101eb74cf5cf79a27.tar.gz
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Tag methods
Diffstat (limited to 'ltm.c')
-rw-r--r--ltm.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/ltm.c b/ltm.c
new file mode 100644
index 00000000..215c7bf5
--- /dev/null
+++ b/ltm.c
@@ -0,0 +1,317 @@
1/*
2** $Id: $
3** Tag methods
4** See Copyright Notice in lua.h
5*/
6
7
8#include <stdio.h>
9#include <string.h>
10
11#include "lauxlib.h"
12#include "ldo.h"
13#include "lmem.h"
14#include "lobject.h"
15#include "ltm.h"
16
17static struct IM init_IM[NUM_TYPES] = {
18{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
19 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
20 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
21 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
22 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
23 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
24{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
25 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
26 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
27 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
28 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
29 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
30{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
31 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
32 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
33 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
34 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
35 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
36{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
37 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
38 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
39 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
40 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
41 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
42{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
43 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
44 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
45 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
46 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
47 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
48{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
49 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
50 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
51 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
52 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
53 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
54{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
55 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
56 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
57 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
58 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
59 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
60{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
61 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
62 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
63 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
64 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
65 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
66{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
67 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
68 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
69 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
70 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
71 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
72{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
73 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
74 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
75 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
76 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
77 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}},
78{{{LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
79 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
80 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
81 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
82 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}},
83 {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}, {LUA_T_NIL, {NULL}}}}
84};
85
86
87
88
89char *luaT_eventname[] = { /* ORDER IM */
90 "gettable", "settable", "index", "getglobal", "setglobal", "add",
91 "sub", "mul", "div", "pow", "unm", "lt", "le", "gt", "ge",
92 "concat", "gc", "function",
93 NULL
94};
95
96
97static int luaI_checkevent (char *name, char *list[])
98{
99 int e = luaO_findstring(name, list);
100 if (e < 0)
101 luaL_verror("`%.50s' is not a valid event name", name);
102 return e;
103}
104
105
106struct IM *luaT_IMtable = init_IM;
107
108static int IMtable_size = NUM_TYPES;
109
110static int last_tag = -(NUM_TYPES-1);
111
112
113/* events in LUA_T_LINE are all allowed, since this is used as a
114* 'placeholder' for "default" fallbacks
115*/
116static char validevents[NUM_TYPES][IM_N] = { /* ORDER LUA_T, ORDER IM */
117{1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1}, /* LUA_T_USERDATA */
118{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, /* LUA_T_LINE */
119{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* LUA_T_CMARK */
120{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* LUA_T_MARK */
121{1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0}, /* LUA_T_CFUNCTION */
122{1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0}, /* LUA_T_FUNCTION */
123{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* LUA_T_PROTO */
124{0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, /* LUA_T_ARRAY */
125{1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}, /* LUA_T_STRING */
126{1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1}, /* LUA_T_NUMBER */
127{1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1} /* LUA_T_NIL */
128};
129
130static int validevent (lua_Type t, int e)
131{ /* ORDER LUA_T */
132 return (t < LUA_T_NIL) ? 1 : validevents[-t][e];
133}
134
135
136static void init_entry (int tag)
137{
138 int i;
139 for (i=0; i<IM_N; i++)
140 ttype(luaT_getim(tag, i)) = LUA_T_NIL;
141}
142
143int lua_newtag (void)
144{
145 --last_tag;
146 if ((-last_tag) >= IMtable_size) {
147 if (luaT_IMtable == init_IM) { /* fist time? */
148 IMtable_size *= 2;
149 luaT_IMtable = luaM_newvector(IMtable_size, struct IM);
150 memcpy(luaT_IMtable, init_IM, sizeof(init_IM));
151 }
152 else
153 IMtable_size = luaM_growvector(&luaT_IMtable, IMtable_size,
154 struct IM, memEM, MAX_INT);
155 }
156 init_entry(last_tag);
157 return last_tag;
158}
159
160
161static void checktag (int tag)
162{ /* ORDER LUA_T */
163 if (!(last_tag <= tag && tag <= 0))
164 luaL_verror("%d is not a valid tag", tag);
165}
166
167void luaT_realtag (int tag)
168{
169 if (!(last_tag <= tag && tag < LUA_T_NIL))
170 luaL_verror("tag %d is not result of `newtag'", tag);
171}
172
173
174
175int luaT_efectivetag (TObject *o)
176{
177 lua_Type t = ttype(o);
178 if (t == LUA_T_USERDATA) {
179 int tag = o->value.ts->tag;
180 return (tag >= 0) ? LUA_T_USERDATA : tag;
181 }
182 else if (t == LUA_T_ARRAY)
183 return o->value.a->htag;
184 else return t;
185}
186
187
188TObject *luaT_gettagmethod (int t, char *event)
189{
190 int e = luaI_checkevent(event, luaT_eventname);
191 checktag(t);
192 if (validevent(t, e))
193 return luaT_getim(t,e);
194 else
195 return luaT_getim(LUA_T_CMARK, IM_GETTABLE); /* always nil */
196}
197
198
199void luaT_settagmethod (int t, char *event, TObject *func)
200{
201 TObject temp = *func;
202 int e = luaI_checkevent(event, luaT_eventname);
203 checktag(t);
204 if (!validevent(t, e))
205 luaL_verror("settagmethod: cannot change internal method `%s' for tag %d",
206 luaT_eventname[e], t);
207 *func = *luaT_getim(t,e);
208 *luaT_getim(t, e) = temp;
209}
210
211
212char *luaT_travtagmethods (int (*fn)(TObject *))
213{
214 int e;
215 if (fn(&luaD_errorim))
216 return "error";
217 for (e=IM_GETTABLE; e<=IM_FUNCTION; e++) { /* ORDER IM */
218 int t;
219 for (t=0; t>=last_tag; t--)
220 if (fn(luaT_getim(t,e)))
221 return luaT_eventname[e];
222 }
223 return NULL;
224}
225
226
227/*
228* ===================================================================
229* compatibility with old fallback system
230*/
231#if LUA_COMPAT2_5
232
233#include "lapi.h"
234
235static void errorFB (void)
236{
237 lua_Object o = lua_getparam(1);
238 if (lua_isstring(o))
239 fprintf(stderr, "lua: %s\n", lua_getstring(o));
240 else
241 fprintf(stderr, "lua: unknown error\n");
242}
243
244
245static void nilFB (void) { }
246
247
248static void typeFB (void)
249{
250 lua_error("unexpected type");
251}
252
253
254static void fillvalids (IMS e, TObject *func)
255{
256 int t;
257 for (t=LUA_T_NIL; t<=LUA_T_USERDATA; t++)
258 if (validevent(t, e))
259 *luaT_getim(t, e) = *func;
260}
261
262
263void luaT_setfallback (void)
264{
265 static char *oldnames [] = {"error", "getglobal", "arith", "order", NULL};
266 TObject oldfunc;
267 lua_CFunction replace;
268 char *name = luaL_check_string(1);
269 lua_Object func = lua_getparam(2);
270 luaL_arg_check(lua_isfunction(func), 2, "function expected");
271 switch (luaO_findstring(name, oldnames)) {
272 case 0: /* old error fallback */
273 oldfunc = luaD_errorim;
274 luaD_errorim = *luaA_Address(func);
275 replace = errorFB;
276 break;
277 case 1: /* old getglobal fallback */
278 oldfunc = *luaT_getim(LUA_T_NIL, IM_GETGLOBAL);
279 *luaT_getim(LUA_T_NIL, IM_GETGLOBAL) = *luaA_Address(func);
280 replace = nilFB;
281 break;
282 case 2: { /* old arith fallback */
283 int i;
284 oldfunc = *luaT_getim(LUA_T_NUMBER, IM_POW);
285 for (i=IM_ADD; i<=IM_UNM; i++) /* ORDER IM */
286 fillvalids(i, luaA_Address(func));
287 replace = typeFB;
288 break;
289 }
290 case 3: { /* old order fallback */
291 int i;
292 oldfunc = *luaT_getim(LUA_T_LINE, IM_LT);
293 for (i=IM_LT; i<=IM_GE; i++) /* ORDER IM */
294 fillvalids(i, luaA_Address(func));
295 replace = typeFB;
296 break;
297 }
298 default: {
299 int e;
300 if ((e = luaO_findstring(name, luaT_eventname)) >= 0) {
301 oldfunc = *luaT_getim(LUA_T_LINE, e);
302 fillvalids(e, luaA_Address(func));
303 replace = (e == IM_GC || e == IM_INDEX) ? nilFB : typeFB;
304 }
305 else {
306 luaL_verror("`%.50s' is not a valid fallback name", name);
307 replace = NULL; /* to avoid warnings */
308 }
309 }
310 }
311 if (oldfunc.ttype != LUA_T_NIL)
312 luaA_pushobject(&oldfunc);
313 else
314 lua_pushcfunction(replace);
315}
316#endif
317
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-03-16 23:50:10 +0000