/src/testdir/build/lua-master/source/ldo.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | ** $Id: ldo.c $ |
3 | | ** Stack and Call structure of Lua |
4 | | ** See Copyright Notice in lua.h |
5 | | */ |
6 | | |
7 | | #define ldo_c |
8 | | #define LUA_CORE |
9 | | |
10 | | #include "lprefix.h" |
11 | | |
12 | | |
13 | | #include <setjmp.h> |
14 | | #include <stdlib.h> |
15 | | #include <string.h> |
16 | | |
17 | | #include "lua.h" |
18 | | |
19 | | #include "lapi.h" |
20 | | #include "ldebug.h" |
21 | | #include "ldo.h" |
22 | | #include "lfunc.h" |
23 | | #include "lgc.h" |
24 | | #include "lmem.h" |
25 | | #include "lobject.h" |
26 | | #include "lopcodes.h" |
27 | | #include "lparser.h" |
28 | | #include "lstate.h" |
29 | | #include "lstring.h" |
30 | | #include "ltable.h" |
31 | | #include "ltm.h" |
32 | | #include "lundump.h" |
33 | | #include "lvm.h" |
34 | | #include "lzio.h" |
35 | | |
36 | | |
37 | | |
38 | 0 | #define errorstatus(s) ((s) > LUA_YIELD) |
39 | | |
40 | | |
41 | | /* |
42 | | ** {====================================================== |
43 | | ** Error-recovery functions |
44 | | ** ======================================================= |
45 | | */ |
46 | | |
47 | | /* |
48 | | ** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By |
49 | | ** default, Lua handles errors with exceptions when compiling as |
50 | | ** C++ code, with _longjmp/_setjmp when asked to use them, and with |
51 | | ** longjmp/setjmp otherwise. |
52 | | */ |
53 | | #if !defined(LUAI_THROW) /* { */ |
54 | | |
55 | | #if defined(__cplusplus) && !defined(LUA_USE_LONGJMP) /* { */ |
56 | | |
57 | | /* C++ exceptions */ |
58 | | #define LUAI_THROW(L,c) throw(c) |
59 | | #define LUAI_TRY(L,c,a) \ |
60 | | try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; } |
61 | | #define luai_jmpbuf int /* dummy variable */ |
62 | | |
63 | | #elif defined(LUA_USE_POSIX) /* }{ */ |
64 | | |
65 | | /* in POSIX, try _longjmp/_setjmp (more efficient) */ |
66 | | #define LUAI_THROW(L,c) _longjmp((c)->b, 1) |
67 | | #define LUAI_TRY(L,c,a) if (_setjmp((c)->b) == 0) { a } |
68 | | #define luai_jmpbuf jmp_buf |
69 | | |
70 | | #else /* }{ */ |
71 | | |
72 | | /* ISO C handling with long jumps */ |
73 | 183k | #define LUAI_THROW(L,c) longjmp((c)->b, 1) |
74 | 491k | #define LUAI_TRY(L,c,a) if (setjmp((c)->b) == 0) { a } |
75 | | #define luai_jmpbuf jmp_buf |
76 | | |
77 | | #endif /* } */ |
78 | | |
79 | | #endif /* } */ |
80 | | |
81 | | |
82 | | |
83 | | /* chain list of long jump buffers */ |
84 | | struct lua_longjmp { |
85 | | struct lua_longjmp *previous; |
86 | | luai_jmpbuf b; |
87 | | volatile int status; /* error code */ |
88 | | }; |
89 | | |
90 | | |
91 | 183k | void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) { |
92 | 183k | switch (errcode) { |
93 | 0 | case LUA_ERRMEM: { /* memory error? */ |
94 | 0 | setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */ |
95 | 0 | break; |
96 | 0 | } |
97 | 0 | case LUA_ERRERR: { |
98 | 0 | setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling")); |
99 | 0 | break; |
100 | 0 | } |
101 | 0 | case LUA_OK: { /* special case only for closing upvalues */ |
102 | 0 | setnilvalue(s2v(oldtop)); /* no error message */ |
103 | 0 | break; |
104 | 0 | } |
105 | 183k | default: { |
106 | 183k | lua_assert(errorstatus(errcode)); /* real error */ |
107 | 183k | setobjs2s(L, oldtop, L->top.p - 1); /* error message on current top */ |
108 | 183k | break; |
109 | 0 | } |
110 | 183k | } |
111 | 183k | L->top.p = oldtop + 1; |
112 | 183k | } |
113 | | |
114 | | |
115 | 183k | l_noret luaD_throw (lua_State *L, int errcode) { |
116 | 183k | if (L->errorJmp) { /* thread has an error handler? */ |
117 | 183k | L->errorJmp->status = errcode; /* set status */ |
118 | 183k | LUAI_THROW(L, L->errorJmp); /* jump to it */ |
119 | 183k | } |
120 | 0 | else { /* thread has no error handler */ |
121 | 0 | global_State *g = G(L); |
122 | 0 | errcode = luaE_resetthread(L, errcode); /* close all upvalues */ |
123 | 0 | if (g->mainthread->errorJmp) { /* main thread has a handler? */ |
124 | 0 | setobjs2s(L, g->mainthread->top.p++, L->top.p - 1); /* copy error obj. */ |
125 | 0 | luaD_throw(g->mainthread, errcode); /* re-throw in main thread */ |
126 | 0 | } |
127 | 0 | else { /* no handler at all; abort */ |
128 | 0 | if (g->panic) { /* panic function? */ |
129 | 0 | lua_unlock(L); |
130 | 0 | g->panic(L); /* call panic function (last chance to jump out) */ |
131 | 0 | } |
132 | 0 | abort(); |
133 | 0 | } |
134 | 0 | } |
135 | 183k | } |
136 | | |
137 | | |
138 | 491k | int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) { |
139 | 491k | l_uint32 oldnCcalls = L->nCcalls; |
140 | 491k | struct lua_longjmp lj; |
141 | 491k | lj.status = LUA_OK; |
142 | 491k | lj.previous = L->errorJmp; /* chain new error handler */ |
143 | 491k | L->errorJmp = &lj; |
144 | 491k | LUAI_TRY(L, &lj, |
145 | 491k | (*f)(L, ud); |
146 | 491k | ); |
147 | 491k | L->errorJmp = lj.previous; /* restore old error handler */ |
148 | 491k | L->nCcalls = oldnCcalls; |
149 | 491k | return lj.status; |
150 | 491k | } |
151 | | |
152 | | /* }====================================================== */ |
153 | | |
154 | | |
155 | | /* |
156 | | ** {================================================================== |
157 | | ** Stack reallocation |
158 | | ** =================================================================== |
159 | | */ |
160 | | |
161 | | |
162 | | /* |
163 | | ** Change all pointers to the stack into offsets. |
164 | | */ |
165 | 6.79k | static void relstack (lua_State *L) { |
166 | 6.79k | CallInfo *ci; |
167 | 6.79k | UpVal *up; |
168 | 6.79k | L->top.offset = savestack(L, L->top.p); |
169 | 6.79k | L->tbclist.offset = savestack(L, L->tbclist.p); |
170 | 7.52k | for (up = L->openupval; up != NULL; up = up->u.open.next) |
171 | 728 | up->v.offset = savestack(L, uplevel(up)); |
172 | 3.98M | for (ci = L->ci; ci != NULL; ci = ci->previous) { |
173 | 3.97M | ci->top.offset = savestack(L, ci->top.p); |
174 | 3.97M | ci->func.offset = savestack(L, ci->func.p); |
175 | 3.97M | } |
176 | 6.79k | } |
177 | | |
178 | | |
179 | | /* |
180 | | ** Change back all offsets into pointers. |
181 | | */ |
182 | 6.79k | static void correctstack (lua_State *L) { |
183 | 6.79k | CallInfo *ci; |
184 | 6.79k | UpVal *up; |
185 | 6.79k | L->top.p = restorestack(L, L->top.offset); |
186 | 6.79k | L->tbclist.p = restorestack(L, L->tbclist.offset); |
187 | 7.52k | for (up = L->openupval; up != NULL; up = up->u.open.next) |
188 | 728 | up->v.p = s2v(restorestack(L, up->v.offset)); |
189 | 3.98M | for (ci = L->ci; ci != NULL; ci = ci->previous) { |
190 | 3.97M | ci->top.p = restorestack(L, ci->top.offset); |
191 | 3.97M | ci->func.p = restorestack(L, ci->func.offset); |
192 | 3.97M | if (isLua(ci)) |
193 | 3.96M | ci->u.l.trap = 1; /* signal to update 'trap' in 'luaV_execute' */ |
194 | 3.97M | } |
195 | 6.79k | } |
196 | | |
197 | | |
198 | | /* some space for error handling */ |
199 | 15 | #define ERRORSTACKSIZE (LUAI_MAXSTACK + 200) |
200 | | |
201 | | /* |
202 | | ** Reallocate the stack to a new size, correcting all pointers into it. |
203 | | ** In ISO C, any pointer use after the pointer has been deallocated is |
204 | | ** undefined behavior. So, before the reallocation, all pointers are |
205 | | ** changed to offsets, and after the reallocation they are changed back |
206 | | ** to pointers. As during the reallocation the pointers are invalid, the |
207 | | ** reallocation cannot run emergency collections. |
208 | | ** |
209 | | ** In case of allocation error, raise an error or return false according |
210 | | ** to 'raiseerror'. |
211 | | */ |
212 | 6.79k | int luaD_reallocstack (lua_State *L, int newsize, int raiseerror) { |
213 | 6.79k | int oldsize = stacksize(L); |
214 | 6.79k | int i; |
215 | 6.79k | StkId newstack; |
216 | 6.79k | int oldgcstop = G(L)->gcstopem; |
217 | 6.79k | lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE); |
218 | 6.79k | relstack(L); /* change pointers to offsets */ |
219 | 6.79k | G(L)->gcstopem = 1; /* stop emergency collection */ |
220 | 6.79k | newstack = luaM_reallocvector(L, L->stack.p, oldsize + EXTRA_STACK, |
221 | 6.79k | newsize + EXTRA_STACK, StackValue); |
222 | 6.79k | G(L)->gcstopem = oldgcstop; /* restore emergency collection */ |
223 | 6.79k | if (l_unlikely(newstack == NULL)) { /* reallocation failed? */ |
224 | 0 | correctstack(L); /* change offsets back to pointers */ |
225 | 0 | if (raiseerror) |
226 | 0 | luaM_error(L); |
227 | 0 | else return 0; /* do not raise an error */ |
228 | 0 | } |
229 | 6.79k | L->stack.p = newstack; |
230 | 6.79k | correctstack(L); /* change offsets back to pointers */ |
231 | 6.79k | L->stack_last.p = L->stack.p + newsize; |
232 | 273M | for (i = oldsize + EXTRA_STACK; i < newsize + EXTRA_STACK; i++) |
233 | 273M | setnilvalue(s2v(newstack + i)); /* erase new segment */ |
234 | 6.79k | return 1; |
235 | 6.79k | } |
236 | | |
237 | | |
238 | | /* |
239 | | ** Try to grow the stack by at least 'n' elements. When 'raiseerror' |
240 | | ** is true, raises any error; otherwise, return 0 in case of errors. |
241 | | */ |
242 | 4.64k | int luaD_growstack (lua_State *L, int n, int raiseerror) { |
243 | 4.64k | int size = stacksize(L); |
244 | 4.64k | if (l_unlikely(size > LUAI_MAXSTACK)) { |
245 | | /* if stack is larger than maximum, thread is already using the |
246 | | extra space reserved for errors, that is, thread is handling |
247 | | a stack error; cannot grow further than that. */ |
248 | 0 | lua_assert(stacksize(L) == ERRORSTACKSIZE); |
249 | 0 | if (raiseerror) |
250 | 0 | luaD_throw(L, LUA_ERRERR); /* error inside message handler */ |
251 | 0 | return 0; /* if not 'raiseerror', just signal it */ |
252 | 0 | } |
253 | 4.64k | else if (n < LUAI_MAXSTACK) { /* avoids arithmetic overflows */ |
254 | 4.64k | int newsize = 2 * size; /* tentative new size */ |
255 | 4.64k | int needed = cast_int(L->top.p - L->stack.p) + n; |
256 | 4.64k | if (newsize > LUAI_MAXSTACK) /* cannot cross the limit */ |
257 | 431 | newsize = LUAI_MAXSTACK; |
258 | 4.64k | if (newsize < needed) /* but must respect what was asked for */ |
259 | 1.39k | newsize = needed; |
260 | 4.64k | if (l_likely(newsize <= LUAI_MAXSTACK)) |
261 | 4.63k | return luaD_reallocstack(L, newsize, raiseerror); |
262 | 4.64k | } |
263 | | /* else stack overflow */ |
264 | | /* add extra size to be able to handle the error message */ |
265 | 15 | luaD_reallocstack(L, ERRORSTACKSIZE, raiseerror); |
266 | 15 | if (raiseerror) |
267 | 14 | luaG_runerror(L, "stack overflow"); |
268 | 1 | return 0; |
269 | 15 | } |
270 | | |
271 | | |
272 | | /* |
273 | | ** Compute how much of the stack is being used, by computing the |
274 | | ** maximum top of all call frames in the stack and the current top. |
275 | | */ |
276 | 300k | static int stackinuse (lua_State *L) { |
277 | 300k | CallInfo *ci; |
278 | 300k | int res; |
279 | 300k | StkId lim = L->top.p; |
280 | 3.65M | for (ci = L->ci; ci != NULL; ci = ci->previous) { |
281 | 3.35M | if (lim < ci->top.p) lim = ci->top.p; |
282 | 3.35M | } |
283 | 300k | lua_assert(lim <= L->stack_last.p + EXTRA_STACK); |
284 | 300k | res = cast_int(lim - L->stack.p) + 1; /* part of stack in use */ |
285 | 300k | if (res < LUA_MINSTACK) |
286 | 0 | res = LUA_MINSTACK; /* ensure a minimum size */ |
287 | 300k | return res; |
288 | 300k | } |
289 | | |
290 | | |
291 | | /* |
292 | | ** If stack size is more than 3 times the current use, reduce that size |
293 | | ** to twice the current use. (So, the final stack size is at most 2/3 the |
294 | | ** previous size, and half of its entries are empty.) |
295 | | ** As a particular case, if stack was handling a stack overflow and now |
296 | | ** it is not, 'max' (limited by LUAI_MAXSTACK) will be smaller than |
297 | | ** stacksize (equal to ERRORSTACKSIZE in this case), and so the stack |
298 | | ** will be reduced to a "regular" size. |
299 | | */ |
300 | 300k | void luaD_shrinkstack (lua_State *L) { |
301 | 300k | int inuse = stackinuse(L); |
302 | 300k | int max = (inuse > LUAI_MAXSTACK / 3) ? LUAI_MAXSTACK : inuse * 3; |
303 | | /* if thread is currently not handling a stack overflow and its |
304 | | size is larger than maximum "reasonable" size, shrink it */ |
305 | 300k | if (inuse <= LUAI_MAXSTACK && stacksize(L) > max) { |
306 | 2.15k | int nsize = (inuse > LUAI_MAXSTACK / 2) ? LUAI_MAXSTACK : inuse * 2; |
307 | 2.15k | luaD_reallocstack(L, nsize, 0); /* ok if that fails */ |
308 | 2.15k | } |
309 | 298k | else /* don't change stack */ |
310 | 298k | condmovestack(L,{},{}); /* (change only for debugging) */ |
311 | 300k | luaE_shrinkCI(L); /* shrink CI list */ |
312 | 300k | } |
313 | | |
314 | | |
315 | 378k | void luaD_inctop (lua_State *L) { |
316 | 378k | luaD_checkstack(L, 1); |
317 | 378k | L->top.p++; |
318 | 378k | } |
319 | | |
320 | | /* }================================================================== */ |
321 | | |
322 | | |
323 | | /* |
324 | | ** Call a hook for the given event. Make sure there is a hook to be |
325 | | ** called. (Both 'L->hook' and 'L->hookmask', which trigger this |
326 | | ** function, can be changed asynchronously by signals.) |
327 | | */ |
328 | | void luaD_hook (lua_State *L, int event, int line, |
329 | 0 | int ftransfer, int ntransfer) { |
330 | 0 | lua_Hook hook = L->hook; |
331 | 0 | if (hook && L->allowhook) { /* make sure there is a hook */ |
332 | 0 | int mask = CIST_HOOKED; |
333 | 0 | CallInfo *ci = L->ci; |
334 | 0 | ptrdiff_t top = savestack(L, L->top.p); /* preserve original 'top' */ |
335 | 0 | ptrdiff_t ci_top = savestack(L, ci->top.p); /* idem for 'ci->top' */ |
336 | 0 | lua_Debug ar; |
337 | 0 | ar.event = event; |
338 | 0 | ar.currentline = line; |
339 | 0 | ar.i_ci = ci; |
340 | 0 | if (ntransfer != 0) { |
341 | 0 | mask |= CIST_TRAN; /* 'ci' has transfer information */ |
342 | 0 | ci->u2.transferinfo.ftransfer = ftransfer; |
343 | 0 | ci->u2.transferinfo.ntransfer = ntransfer; |
344 | 0 | } |
345 | 0 | if (isLua(ci) && L->top.p < ci->top.p) |
346 | 0 | L->top.p = ci->top.p; /* protect entire activation register */ |
347 | 0 | luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ |
348 | 0 | if (ci->top.p < L->top.p + LUA_MINSTACK) |
349 | 0 | ci->top.p = L->top.p + LUA_MINSTACK; |
350 | 0 | L->allowhook = 0; /* cannot call hooks inside a hook */ |
351 | 0 | ci->callstatus |= mask; |
352 | 0 | lua_unlock(L); |
353 | 0 | (*hook)(L, &ar); |
354 | 0 | lua_lock(L); |
355 | 0 | lua_assert(!L->allowhook); |
356 | 0 | L->allowhook = 1; |
357 | 0 | ci->top.p = restorestack(L, ci_top); |
358 | 0 | L->top.p = restorestack(L, top); |
359 | 0 | ci->callstatus &= ~mask; |
360 | 0 | } |
361 | 0 | } |
362 | | |
363 | | |
364 | | /* |
365 | | ** Executes a call hook for Lua functions. This function is called |
366 | | ** whenever 'hookmask' is not zero, so it checks whether call hooks are |
367 | | ** active. |
368 | | */ |
369 | 1.10k | void luaD_hookcall (lua_State *L, CallInfo *ci) { |
370 | 1.10k | L->oldpc = 0; /* set 'oldpc' for new function */ |
371 | 1.10k | if (L->hookmask & LUA_MASKCALL) { /* is call hook on? */ |
372 | 0 | int event = (ci->callstatus & CIST_TAIL) ? LUA_HOOKTAILCALL |
373 | 0 | : LUA_HOOKCALL; |
374 | 0 | Proto *p = ci_func(ci)->p; |
375 | 0 | ci->u.l.savedpc++; /* hooks assume 'pc' is already incremented */ |
376 | 0 | luaD_hook(L, event, -1, 1, p->numparams); |
377 | 0 | ci->u.l.savedpc--; /* correct 'pc' */ |
378 | 0 | } |
379 | 1.10k | } |
380 | | |
381 | | |
382 | | /* |
383 | | ** Executes a return hook for Lua and C functions and sets/corrects |
384 | | ** 'oldpc'. (Note that this correction is needed by the line hook, so it |
385 | | ** is done even when return hooks are off.) |
386 | | */ |
387 | 0 | static void rethook (lua_State *L, CallInfo *ci, int nres) { |
388 | 0 | if (L->hookmask & LUA_MASKRET) { /* is return hook on? */ |
389 | 0 | StkId firstres = L->top.p - nres; /* index of first result */ |
390 | 0 | int delta = 0; /* correction for vararg functions */ |
391 | 0 | int ftransfer; |
392 | 0 | if (isLua(ci)) { |
393 | 0 | Proto *p = ci_func(ci)->p; |
394 | 0 | if (p->is_vararg) |
395 | 0 | delta = ci->u.l.nextraargs + p->numparams + 1; |
396 | 0 | } |
397 | 0 | ci->func.p += delta; /* if vararg, back to virtual 'func' */ |
398 | 0 | ftransfer = cast(unsigned short, firstres - ci->func.p); |
399 | 0 | luaD_hook(L, LUA_HOOKRET, -1, ftransfer, nres); /* call it */ |
400 | 0 | ci->func.p -= delta; |
401 | 0 | } |
402 | 0 | if (isLua(ci = ci->previous)) |
403 | 0 | L->oldpc = pcRel(ci->u.l.savedpc, ci_func(ci)->p); /* set 'oldpc' */ |
404 | 0 | } |
405 | | |
406 | | |
407 | | /* |
408 | | ** Check whether 'func' has a '__call' metafield. If so, put it in the |
409 | | ** stack, below original 'func', so that 'luaD_precall' can call it. Raise |
410 | | ** an error if there is no '__call' metafield. |
411 | | */ |
412 | 6.06k | static StkId tryfuncTM (lua_State *L, StkId func) { |
413 | 6.06k | const TValue *tm; |
414 | 6.06k | StkId p; |
415 | 6.06k | checkstackGCp(L, 1, func); /* space for metamethod */ |
416 | 6.06k | tm = luaT_gettmbyobj(L, s2v(func), TM_CALL); /* (after previous GC) */ |
417 | 6.06k | if (l_unlikely(ttisnil(tm))) |
418 | 6.06k | luaG_callerror(L, s2v(func)); /* nothing to call */ |
419 | 0 | for (p = L->top.p; p > func; p--) /* open space for metamethod */ |
420 | 0 | setobjs2s(L, p, p-1); |
421 | 0 | L->top.p++; /* stack space pre-allocated by the caller */ |
422 | 0 | setobj2s(L, func, tm); /* metamethod is the new function to be called */ |
423 | 0 | return func; |
424 | 6.06k | } |
425 | | |
426 | | |
427 | | /* |
428 | | ** Given 'nres' results at 'firstResult', move 'wanted' of them to 'res'. |
429 | | ** Handle most typical cases (zero results for commands, one result for |
430 | | ** expressions, multiple results for tail calls/single parameters) |
431 | | ** separated. |
432 | | */ |
433 | 1.75M | l_sinline void moveresults (lua_State *L, StkId res, int nres, int wanted) { |
434 | 1.75M | StkId firstresult; |
435 | 1.75M | int i; |
436 | 1.75M | switch (wanted) { /* handle typical cases separately */ |
437 | 272k | case 0: /* no values needed */ |
438 | 272k | L->top.p = res; |
439 | 272k | return; |
440 | 1.41M | case 1: /* one value needed */ |
441 | 1.41M | if (nres == 0) /* no results? */ |
442 | 1.41M | setnilvalue(s2v(res)); /* adjust with nil */ |
443 | 1.40M | else /* at least one result */ |
444 | 1.41M | setobjs2s(L, res, L->top.p - nres); /* move it to proper place */ |
445 | 1.41M | L->top.p = res + 1; |
446 | 1.41M | return; |
447 | 7.97k | case LUA_MULTRET: |
448 | 7.97k | wanted = nres; /* we want all results */ |
449 | 7.97k | break; |
450 | 58.3k | default: /* two/more results and/or to-be-closed variables */ |
451 | 58.3k | if (hastocloseCfunc(wanted)) { /* to-be-closed variables? */ |
452 | 49.1k | L->ci->callstatus |= CIST_CLSRET; /* in case of yields */ |
453 | 49.1k | L->ci->u2.nres = nres; |
454 | 49.1k | res = luaF_close(L, res, CLOSEKTOP, 1); |
455 | 49.1k | L->ci->callstatus &= ~CIST_CLSRET; |
456 | 49.1k | if (L->hookmask) { /* if needed, call hook after '__close's */ |
457 | 0 | ptrdiff_t savedres = savestack(L, res); |
458 | 0 | rethook(L, L->ci, nres); |
459 | 0 | res = restorestack(L, savedres); /* hook can move stack */ |
460 | 0 | } |
461 | 49.1k | wanted = decodeNresults(wanted); |
462 | 49.1k | if (wanted == LUA_MULTRET) |
463 | 570 | wanted = nres; /* we want all results */ |
464 | 49.1k | } |
465 | 58.3k | break; |
466 | 1.75M | } |
467 | | /* generic case */ |
468 | 66.2k | firstresult = L->top.p - nres; /* index of first result */ |
469 | 66.2k | if (nres > wanted) /* extra results? */ |
470 | 14.3k | nres = wanted; /* don't need them */ |
471 | 424M | for (i = 0; i < nres; i++) /* move all results to correct place */ |
472 | 424M | setobjs2s(L, res + i, firstresult + i); |
473 | 179k | for (; i < wanted; i++) /* complete wanted number of results */ |
474 | 113k | setnilvalue(s2v(res + i)); |
475 | 66.2k | L->top.p = res + wanted; /* top points after the last result */ |
476 | 66.2k | } |
477 | | |
478 | | |
479 | | /* |
480 | | ** Finishes a function call: calls hook if necessary, moves current |
481 | | ** number of results to proper place, and returns to previous call |
482 | | ** info. If function has to close variables, hook must be called after |
483 | | ** that. |
484 | | */ |
485 | 1.75M | void luaD_poscall (lua_State *L, CallInfo *ci, int nres) { |
486 | 1.75M | int wanted = ci->nresults; |
487 | 1.75M | if (l_unlikely(L->hookmask && !hastocloseCfunc(wanted))) |
488 | 0 | rethook(L, ci, nres); |
489 | | /* move results to proper place */ |
490 | 1.75M | moveresults(L, ci->func.p, nres, wanted); |
491 | | /* function cannot be in any of these cases when returning */ |
492 | 1.75M | lua_assert(!(ci->callstatus & |
493 | 1.75M | (CIST_HOOKED | CIST_YPCALL | CIST_FIN | CIST_TRAN | CIST_CLSRET))); |
494 | 1.75M | L->ci = ci->previous; /* back to caller (after closing variables) */ |
495 | 1.75M | } |
496 | | |
497 | | |
498 | | |
499 | 3.06M | #define next_ci(L) (L->ci->next ? L->ci->next : luaE_extendCI(L)) |
500 | | |
501 | | |
502 | | l_sinline CallInfo *prepCallInfo (lua_State *L, StkId func, int nret, |
503 | 3.06M | int mask, StkId top) { |
504 | 3.06M | CallInfo *ci = L->ci = next_ci(L); /* new frame */ |
505 | 3.06M | ci->func.p = func; |
506 | 3.06M | ci->nresults = nret; |
507 | 3.06M | ci->callstatus = mask; |
508 | 3.06M | ci->top.p = top; |
509 | 3.06M | return ci; |
510 | 3.06M | } |
511 | | |
512 | | |
513 | | /* |
514 | | ** precall for C functions |
515 | | */ |
516 | | l_sinline int precallC (lua_State *L, StkId func, int nresults, |
517 | 1.75M | lua_CFunction f) { |
518 | 1.75M | int n; /* number of returns */ |
519 | 1.75M | CallInfo *ci; |
520 | 1.75M | checkstackGCp(L, LUA_MINSTACK, func); /* ensure minimum stack size */ |
521 | 1.75M | L->ci = ci = prepCallInfo(L, func, nresults, CIST_C, |
522 | 1.75M | L->top.p + LUA_MINSTACK); |
523 | 1.75M | lua_assert(ci->top.p <= L->stack_last.p); |
524 | 1.75M | if (l_unlikely(L->hookmask & LUA_MASKCALL)) { |
525 | 0 | int narg = cast_int(L->top.p - func) - 1; |
526 | 0 | luaD_hook(L, LUA_HOOKCALL, -1, 1, narg); |
527 | 0 | } |
528 | 1.75M | lua_unlock(L); |
529 | 1.75M | n = (*f)(L); /* do the actual call */ |
530 | 1.75M | lua_lock(L); |
531 | 1.75M | api_checknelems(L, n); |
532 | 1.74M | luaD_poscall(L, ci, n); |
533 | 1.74M | return n; |
534 | 1.75M | } |
535 | | |
536 | | |
537 | | /* |
538 | | ** Prepare a function for a tail call, building its call info on top |
539 | | ** of the current call info. 'narg1' is the number of arguments plus 1 |
540 | | ** (so that it includes the function itself). Return the number of |
541 | | ** results, if it was a C function, or -1 for a Lua function. |
542 | | */ |
543 | | int luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func, |
544 | 886 | int narg1, int delta) { |
545 | 886 | retry: |
546 | 886 | switch (ttypetag(s2v(func))) { |
547 | 0 | case LUA_VCCL: /* C closure */ |
548 | 0 | return precallC(L, func, LUA_MULTRET, clCvalue(s2v(func))->f); |
549 | 72 | case LUA_VLCF: /* light C function */ |
550 | 72 | return precallC(L, func, LUA_MULTRET, fvalue(s2v(func))); |
551 | 812 | case LUA_VLCL: { /* Lua function */ |
552 | 812 | Proto *p = clLvalue(s2v(func))->p; |
553 | 812 | int fsize = p->maxstacksize; /* frame size */ |
554 | 812 | int nfixparams = p->numparams; |
555 | 812 | int i; |
556 | 812 | checkstackGCp(L, fsize - delta, func); |
557 | 812 | ci->func.p -= delta; /* restore 'func' (if vararg) */ |
558 | 3.86k | for (i = 0; i < narg1; i++) /* move down function and arguments */ |
559 | 3.05k | setobjs2s(L, ci->func.p + i, func + i); |
560 | 812 | func = ci->func.p; /* moved-down function */ |
561 | 812 | for (; narg1 <= nfixparams; narg1++) |
562 | 812 | setnilvalue(s2v(func + narg1)); /* complete missing arguments */ |
563 | 812 | ci->top.p = func + 1 + fsize; /* top for new function */ |
564 | 812 | lua_assert(ci->top.p <= L->stack_last.p); |
565 | 812 | ci->u.l.savedpc = p->code; /* starting point */ |
566 | 812 | ci->callstatus |= CIST_TAIL; |
567 | 812 | L->top.p = func + narg1; /* set top */ |
568 | 812 | return -1; |
569 | 0 | } |
570 | 2 | default: { /* not a function */ |
571 | 2 | func = tryfuncTM(L, func); /* try to get '__call' metamethod */ |
572 | | /* return luaD_pretailcall(L, ci, func, narg1 + 1, delta); */ |
573 | 2 | narg1++; |
574 | 2 | goto retry; /* try again */ |
575 | 0 | } |
576 | 886 | } |
577 | 886 | } |
578 | | |
579 | | |
580 | | /* |
581 | | ** Prepares the call to a function (C or Lua). For C functions, also do |
582 | | ** the call. The function to be called is at '*func'. The arguments |
583 | | ** are on the stack, right after the function. Returns the CallInfo |
584 | | ** to be executed, if it was a Lua function. Otherwise (a C function) |
585 | | ** returns NULL, with all the results on the stack, starting at the |
586 | | ** original function position. |
587 | | */ |
588 | 3.07M | CallInfo *luaD_precall (lua_State *L, StkId func, int nresults) { |
589 | 3.07M | retry: |
590 | 3.07M | switch (ttypetag(s2v(func))) { |
591 | 3.54k | case LUA_VCCL: /* C closure */ |
592 | 3.54k | precallC(L, func, nresults, clCvalue(s2v(func))->f); |
593 | 3.54k | return NULL; |
594 | 1.74M | case LUA_VLCF: /* light C function */ |
595 | 1.74M | precallC(L, func, nresults, fvalue(s2v(func))); |
596 | 1.74M | return NULL; |
597 | 1.31M | case LUA_VLCL: { /* Lua function */ |
598 | 1.31M | CallInfo *ci; |
599 | 1.31M | Proto *p = clLvalue(s2v(func))->p; |
600 | 1.31M | int narg = cast_int(L->top.p - func) - 1; /* number of real arguments */ |
601 | 1.31M | int nfixparams = p->numparams; |
602 | 1.31M | int fsize = p->maxstacksize; /* frame size */ |
603 | 1.31M | checkstackGCp(L, fsize, func); |
604 | 1.31M | L->ci = ci = prepCallInfo(L, func, nresults, 0, func + 1 + fsize); |
605 | 1.31M | ci->u.l.savedpc = p->code; /* starting point */ |
606 | 2.18M | for (; narg < nfixparams; narg++) |
607 | 1.31M | setnilvalue(s2v(L->top.p++)); /* complete missing arguments */ |
608 | 1.31M | lua_assert(ci->top.p <= L->stack_last.p); |
609 | 1.31M | return ci; |
610 | 0 | } |
611 | 6.06k | default: { /* not a function */ |
612 | 6.06k | func = tryfuncTM(L, func); /* try to get '__call' metamethod */ |
613 | | /* return luaD_precall(L, func, nresults); */ |
614 | 6.06k | goto retry; /* try again with metamethod */ |
615 | 0 | } |
616 | 3.07M | } |
617 | 3.07M | } |
618 | | |
619 | | |
620 | | /* |
621 | | ** Call a function (C or Lua) through C. 'inc' can be 1 (increment |
622 | | ** number of recursive invocations in the C stack) or nyci (the same |
623 | | ** plus increment number of non-yieldable calls). |
624 | | ** This function can be called with some use of EXTRA_STACK, so it should |
625 | | ** check the stack before doing anything else. 'luaD_precall' already |
626 | | ** does that. |
627 | | */ |
628 | 1.19M | l_sinline void ccall (lua_State *L, StkId func, int nResults, l_uint32 inc) { |
629 | 1.19M | CallInfo *ci; |
630 | 1.19M | L->nCcalls += inc; |
631 | 1.19M | if (l_unlikely(getCcalls(L) >= LUAI_MAXCCALLS)) { |
632 | 0 | checkstackp(L, 0, func); /* free any use of EXTRA_STACK */ |
633 | 0 | luaE_checkcstack(L); |
634 | 0 | } |
635 | 1.19M | if ((ci = luaD_precall(L, func, nResults)) != NULL) { /* Lua function? */ |
636 | 5.73k | ci->callstatus = CIST_FRESH; /* mark that it is a "fresh" execute */ |
637 | 5.73k | luaV_execute(L, ci); /* call it */ |
638 | 5.73k | } |
639 | 1.19M | L->nCcalls -= inc; |
640 | 1.19M | } |
641 | | |
642 | | |
643 | | /* |
644 | | ** External interface for 'ccall' |
645 | | */ |
646 | 1.03M | void luaD_call (lua_State *L, StkId func, int nResults) { |
647 | 1.03M | ccall(L, func, nResults, 1); |
648 | 1.03M | } |
649 | | |
650 | | |
651 | | /* |
652 | | ** Similar to 'luaD_call', but does not allow yields during the call. |
653 | | */ |
654 | 167k | void luaD_callnoyield (lua_State *L, StkId func, int nResults) { |
655 | 167k | ccall(L, func, nResults, nyci); |
656 | 167k | } |
657 | | |
658 | | |
659 | | /* |
660 | | ** Finish the job of 'lua_pcallk' after it was interrupted by an yield. |
661 | | ** (The caller, 'finishCcall', does the final call to 'adjustresults'.) |
662 | | ** The main job is to complete the 'luaD_pcall' called by 'lua_pcallk'. |
663 | | ** If a '__close' method yields here, eventually control will be back |
664 | | ** to 'finishCcall' (when that '__close' method finally returns) and |
665 | | ** 'finishpcallk' will run again and close any still pending '__close' |
666 | | ** methods. Similarly, if a '__close' method errs, 'precover' calls |
667 | | ** 'unroll' which calls ''finishCcall' and we are back here again, to |
668 | | ** close any pending '__close' methods. |
669 | | ** Note that, up to the call to 'luaF_close', the corresponding |
670 | | ** 'CallInfo' is not modified, so that this repeated run works like the |
671 | | ** first one (except that it has at least one less '__close' to do). In |
672 | | ** particular, field CIST_RECST preserves the error status across these |
673 | | ** multiple runs, changing only if there is a new error. |
674 | | */ |
675 | 0 | static int finishpcallk (lua_State *L, CallInfo *ci) { |
676 | 0 | int status = getcistrecst(ci); /* get original status */ |
677 | 0 | if (l_likely(status == LUA_OK)) /* no error? */ |
678 | 0 | status = LUA_YIELD; /* was interrupted by an yield */ |
679 | 0 | else { /* error */ |
680 | 0 | StkId func = restorestack(L, ci->u2.funcidx); |
681 | 0 | L->allowhook = getoah(ci->callstatus); /* restore 'allowhook' */ |
682 | 0 | func = luaF_close(L, func, status, 1); /* can yield or raise an error */ |
683 | 0 | luaD_seterrorobj(L, status, func); |
684 | 0 | luaD_shrinkstack(L); /* restore stack size in case of overflow */ |
685 | 0 | setcistrecst(ci, LUA_OK); /* clear original status */ |
686 | 0 | } |
687 | 0 | ci->callstatus &= ~CIST_YPCALL; |
688 | 0 | L->errfunc = ci->u.c.old_errfunc; |
689 | | /* if it is here, there were errors or yields; unlike 'lua_pcallk', |
690 | | do not change status */ |
691 | 0 | return status; |
692 | 0 | } |
693 | | |
694 | | |
695 | | /* |
696 | | ** Completes the execution of a C function interrupted by an yield. |
697 | | ** The interruption must have happened while the function was either |
698 | | ** closing its tbc variables in 'moveresults' or executing |
699 | | ** 'lua_callk'/'lua_pcallk'. In the first case, it just redoes |
700 | | ** 'luaD_poscall'. In the second case, the call to 'finishpcallk' |
701 | | ** finishes the interrupted execution of 'lua_pcallk'. After that, it |
702 | | ** calls the continuation of the interrupted function and finally it |
703 | | ** completes the job of the 'luaD_call' that called the function. In |
704 | | ** the call to 'adjustresults', we do not know the number of results |
705 | | ** of the function called by 'lua_callk'/'lua_pcallk', so we are |
706 | | ** conservative and use LUA_MULTRET (always adjust). |
707 | | */ |
708 | 0 | static void finishCcall (lua_State *L, CallInfo *ci) { |
709 | 0 | int n; /* actual number of results from C function */ |
710 | 0 | if (ci->callstatus & CIST_CLSRET) { /* was returning? */ |
711 | 0 | lua_assert(hastocloseCfunc(ci->nresults)); |
712 | 0 | n = ci->u2.nres; /* just redo 'luaD_poscall' */ |
713 | | /* don't need to reset CIST_CLSRET, as it will be set again anyway */ |
714 | 0 | } |
715 | 0 | else { |
716 | 0 | int status = LUA_YIELD; /* default if there were no errors */ |
717 | | /* must have a continuation and must be able to call it */ |
718 | 0 | lua_assert(ci->u.c.k != NULL && yieldable(L)); |
719 | 0 | if (ci->callstatus & CIST_YPCALL) /* was inside a 'lua_pcallk'? */ |
720 | 0 | status = finishpcallk(L, ci); /* finish it */ |
721 | 0 | adjustresults(L, LUA_MULTRET); /* finish 'lua_callk' */ |
722 | 0 | lua_unlock(L); |
723 | 0 | n = (*ci->u.c.k)(L, status, ci->u.c.ctx); /* call continuation */ |
724 | 0 | lua_lock(L); |
725 | 0 | api_checknelems(L, n); |
726 | 0 | } |
727 | 0 | luaD_poscall(L, ci, n); /* finish 'luaD_call' */ |
728 | 0 | } |
729 | | |
730 | | |
731 | | /* |
732 | | ** Executes "full continuation" (everything in the stack) of a |
733 | | ** previously interrupted coroutine until the stack is empty (or another |
734 | | ** interruption long-jumps out of the loop). |
735 | | */ |
736 | 0 | static void unroll (lua_State *L, void *ud) { |
737 | 0 | CallInfo *ci; |
738 | 0 | UNUSED(ud); |
739 | 0 | while ((ci = L->ci) != &L->base_ci) { /* something in the stack */ |
740 | 0 | if (!isLua(ci)) /* C function? */ |
741 | 0 | finishCcall(L, ci); /* complete its execution */ |
742 | 0 | else { /* Lua function */ |
743 | 0 | luaV_finishOp(L); /* finish interrupted instruction */ |
744 | 0 | luaV_execute(L, ci); /* execute down to higher C 'boundary' */ |
745 | 0 | } |
746 | 0 | } |
747 | 0 | } |
748 | | |
749 | | |
750 | | /* |
751 | | ** Try to find a suspended protected call (a "recover point") for the |
752 | | ** given thread. |
753 | | */ |
754 | 0 | static CallInfo *findpcall (lua_State *L) { |
755 | 0 | CallInfo *ci; |
756 | 0 | for (ci = L->ci; ci != NULL; ci = ci->previous) { /* search for a pcall */ |
757 | 0 | if (ci->callstatus & CIST_YPCALL) |
758 | 0 | return ci; |
759 | 0 | } |
760 | 0 | return NULL; /* no pending pcall */ |
761 | 0 | } |
762 | | |
763 | | |
764 | | /* |
765 | | ** Signal an error in the call to 'lua_resume', not in the execution |
766 | | ** of the coroutine itself. (Such errors should not be handled by any |
767 | | ** coroutine error handler and should not kill the coroutine.) |
768 | | */ |
769 | 0 | static int resume_error (lua_State *L, const char *msg, int narg) { |
770 | 0 | L->top.p -= narg; /* remove args from the stack */ |
771 | 0 | setsvalue2s(L, L->top.p, luaS_new(L, msg)); /* push error message */ |
772 | 0 | api_incr_top(L); |
773 | 0 | lua_unlock(L); |
774 | 0 | return LUA_ERRRUN; |
775 | 0 | } |
776 | | |
777 | | |
778 | | /* |
779 | | ** Do the work for 'lua_resume' in protected mode. Most of the work |
780 | | ** depends on the status of the coroutine: initial state, suspended |
781 | | ** inside a hook, or regularly suspended (optionally with a continuation |
782 | | ** function), plus erroneous cases: non-suspended coroutine or dead |
783 | | ** coroutine. |
784 | | */ |
785 | 0 | static void resume (lua_State *L, void *ud) { |
786 | 0 | int n = *(cast(int*, ud)); /* number of arguments */ |
787 | 0 | StkId firstArg = L->top.p - n; /* first argument */ |
788 | 0 | CallInfo *ci = L->ci; |
789 | 0 | if (L->status == LUA_OK) /* starting a coroutine? */ |
790 | 0 | ccall(L, firstArg - 1, LUA_MULTRET, 0); /* just call its body */ |
791 | 0 | else { /* resuming from previous yield */ |
792 | 0 | lua_assert(L->status == LUA_YIELD); |
793 | 0 | L->status = LUA_OK; /* mark that it is running (again) */ |
794 | 0 | if (isLua(ci)) { /* yielded inside a hook? */ |
795 | 0 | L->top.p = firstArg; /* discard arguments */ |
796 | 0 | luaV_execute(L, ci); /* just continue running Lua code */ |
797 | 0 | } |
798 | 0 | else { /* 'common' yield */ |
799 | 0 | if (ci->u.c.k != NULL) { /* does it have a continuation function? */ |
800 | 0 | lua_unlock(L); |
801 | 0 | n = (*ci->u.c.k)(L, LUA_YIELD, ci->u.c.ctx); /* call continuation */ |
802 | 0 | lua_lock(L); |
803 | 0 | api_checknelems(L, n); |
804 | 0 | } |
805 | 0 | luaD_poscall(L, ci, n); /* finish 'luaD_call' */ |
806 | 0 | } |
807 | 0 | unroll(L, NULL); /* run continuation */ |
808 | 0 | } |
809 | 0 | } |
810 | | |
811 | | |
812 | | /* |
813 | | ** Unrolls a coroutine in protected mode while there are recoverable |
814 | | ** errors, that is, errors inside a protected call. (Any error |
815 | | ** interrupts 'unroll', and this loop protects it again so it can |
816 | | ** continue.) Stops with a normal end (status == LUA_OK), an yield |
817 | | ** (status == LUA_YIELD), or an unprotected error ('findpcall' doesn't |
818 | | ** find a recover point). |
819 | | */ |
820 | 0 | static int precover (lua_State *L, int status) { |
821 | 0 | CallInfo *ci; |
822 | 0 | while (errorstatus(status) && (ci = findpcall(L)) != NULL) { |
823 | 0 | L->ci = ci; /* go down to recovery functions */ |
824 | 0 | setcistrecst(ci, status); /* status to finish 'pcall' */ |
825 | 0 | status = luaD_rawrunprotected(L, unroll, NULL); |
826 | 0 | } |
827 | 0 | return status; |
828 | 0 | } |
829 | | |
830 | | |
831 | | LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs, |
832 | 0 | int *nresults) { |
833 | 0 | int status; |
834 | 0 | lua_lock(L); |
835 | 0 | if (L->status == LUA_OK) { /* may be starting a coroutine */ |
836 | 0 | if (L->ci != &L->base_ci) /* not in base level? */ |
837 | 0 | return resume_error(L, "cannot resume non-suspended coroutine", nargs); |
838 | 0 | else if (L->top.p - (L->ci->func.p + 1) == nargs) /* no function? */ |
839 | 0 | return resume_error(L, "cannot resume dead coroutine", nargs); |
840 | 0 | } |
841 | 0 | else if (L->status != LUA_YIELD) /* ended with errors? */ |
842 | 0 | return resume_error(L, "cannot resume dead coroutine", nargs); |
843 | 0 | L->nCcalls = (from) ? getCcalls(from) : 0; |
844 | 0 | if (getCcalls(L) >= LUAI_MAXCCALLS) |
845 | 0 | return resume_error(L, "C stack overflow", nargs); |
846 | 0 | L->nCcalls++; |
847 | 0 | luai_userstateresume(L, nargs); |
848 | 0 | api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs); |
849 | 0 | status = luaD_rawrunprotected(L, resume, &nargs); |
850 | | /* continue running after recoverable errors */ |
851 | 0 | status = precover(L, status); |
852 | 0 | if (l_likely(!errorstatus(status))) |
853 | 0 | lua_assert(status == L->status); /* normal end or yield */ |
854 | 0 | else { /* unrecoverable error */ |
855 | 0 | L->status = cast_byte(status); /* mark thread as 'dead' */ |
856 | 0 | luaD_seterrorobj(L, status, L->top.p); /* push error message */ |
857 | 0 | L->ci->top.p = L->top.p; |
858 | 0 | } |
859 | 0 | *nresults = (status == LUA_YIELD) ? L->ci->u2.nyield |
860 | 0 | : cast_int(L->top.p - (L->ci->func.p + 1)); |
861 | 0 | lua_unlock(L); |
862 | 0 | return status; |
863 | 0 | } |
864 | | |
865 | | |
866 | 0 | LUA_API int lua_isyieldable (lua_State *L) { |
867 | 0 | return yieldable(L); |
868 | 0 | } |
869 | | |
870 | | |
871 | | LUA_API int lua_yieldk (lua_State *L, int nresults, lua_KContext ctx, |
872 | 0 | lua_KFunction k) { |
873 | 0 | CallInfo *ci; |
874 | 0 | luai_userstateyield(L, nresults); |
875 | 0 | lua_lock(L); |
876 | 0 | ci = L->ci; |
877 | 0 | api_checknelems(L, nresults); |
878 | 0 | if (l_unlikely(!yieldable(L))) { |
879 | 0 | if (L != G(L)->mainthread) |
880 | 0 | luaG_runerror(L, "attempt to yield across a C-call boundary"); |
881 | 0 | else |
882 | 0 | luaG_runerror(L, "attempt to yield from outside a coroutine"); |
883 | 0 | } |
884 | 0 | L->status = LUA_YIELD; |
885 | 0 | ci->u2.nyield = nresults; /* save number of results */ |
886 | 0 | if (isLua(ci)) { /* inside a hook? */ |
887 | 0 | lua_assert(!isLuacode(ci)); |
888 | 0 | api_check(L, nresults == 0, "hooks cannot yield values"); |
889 | 0 | api_check(L, k == NULL, "hooks cannot continue after yielding"); |
890 | 0 | } |
891 | 0 | else { |
892 | 0 | if ((ci->u.c.k = k) != NULL) /* is there a continuation? */ |
893 | 0 | ci->u.c.ctx = ctx; /* save context */ |
894 | 0 | luaD_throw(L, LUA_YIELD); |
895 | 0 | } |
896 | 0 | lua_assert(ci->callstatus & CIST_HOOKED); /* must be inside a hook */ |
897 | 0 | lua_unlock(L); |
898 | 0 | return 0; /* return to 'luaD_hook' */ |
899 | 0 | } |
900 | | |
901 | | |
902 | | /* |
903 | | ** Auxiliary structure to call 'luaF_close' in protected mode. |
904 | | */ |
905 | | struct CloseP { |
906 | | StkId level; |
907 | | int status; |
908 | | }; |
909 | | |
910 | | |
911 | | /* |
912 | | ** Auxiliary function to call 'luaF_close' in protected mode. |
913 | | */ |
914 | 198k | static void closepaux (lua_State *L, void *ud) { |
915 | 198k | struct CloseP *pcl = cast(struct CloseP *, ud); |
916 | 198k | luaF_close(L, pcl->level, pcl->status, 0); |
917 | 198k | } |
918 | | |
919 | | |
920 | | /* |
921 | | ** Calls 'luaF_close' in protected mode. Return the original status |
922 | | ** or, in case of errors, the new status. |
923 | | */ |
924 | 198k | int luaD_closeprotected (lua_State *L, ptrdiff_t level, int status) { |
925 | 198k | CallInfo *old_ci = L->ci; |
926 | 198k | lu_byte old_allowhooks = L->allowhook; |
927 | 198k | for (;;) { /* keep closing upvalues until no more errors */ |
928 | 198k | struct CloseP pcl; |
929 | 198k | pcl.level = restorestack(L, level); pcl.status = status; |
930 | 198k | status = luaD_rawrunprotected(L, &closepaux, &pcl); |
931 | 198k | if (l_likely(status == LUA_OK)) /* no more errors? */ |
932 | 198k | return pcl.status; |
933 | 0 | else { /* an error occurred; restore saved state and repeat */ |
934 | 0 | L->ci = old_ci; |
935 | 0 | L->allowhook = old_allowhooks; |
936 | 0 | } |
937 | 198k | } |
938 | 198k | } |
939 | | |
940 | | |
941 | | /* |
942 | | ** Call the C function 'func' in protected mode, restoring basic |
943 | | ** thread information ('allowhook', etc.) and in particular |
944 | | ** its stack level in case of errors. |
945 | | */ |
946 | | int luaD_pcall (lua_State *L, Pfunc func, void *u, |
947 | 276k | ptrdiff_t old_top, ptrdiff_t ef) { |
948 | 276k | int status; |
949 | 276k | CallInfo *old_ci = L->ci; |
950 | 276k | lu_byte old_allowhooks = L->allowhook; |
951 | 276k | ptrdiff_t old_errfunc = L->errfunc; |
952 | 276k | L->errfunc = ef; |
953 | 276k | status = luaD_rawrunprotected(L, func, u); |
954 | 276k | if (l_unlikely(status != LUA_OK)) { /* an error occurred? */ |
955 | 183k | L->ci = old_ci; |
956 | 183k | L->allowhook = old_allowhooks; |
957 | 183k | status = luaD_closeprotected(L, old_top, status); |
958 | 183k | luaD_seterrorobj(L, status, restorestack(L, old_top)); |
959 | 183k | luaD_shrinkstack(L); /* restore stack size in case of overflow */ |
960 | 183k | } |
961 | 276k | L->errfunc = old_errfunc; |
962 | 276k | return status; |
963 | 276k | } |
964 | | |
965 | | |
966 | | |
967 | | /* |
968 | | ** Execute a protected parser. |
969 | | */ |
970 | | struct SParser { /* data to 'f_parser' */ |
971 | | ZIO *z; |
972 | | Mbuffer buff; /* dynamic structure used by the scanner */ |
973 | | Dyndata dyd; /* dynamic structures used by the parser */ |
974 | | const char *mode; |
975 | | const char *name; |
976 | | }; |
977 | | |
978 | | |
979 | 195k | static void checkmode (lua_State *L, const char *mode, const char *x) { |
980 | 195k | if (mode && strchr(mode, x[0]) == NULL) { |
981 | 0 | luaO_pushfstring(L, |
982 | 0 | "attempt to load a %s chunk (mode is '%s')", x, mode); |
983 | 0 | luaD_throw(L, LUA_ERRSYNTAX); |
984 | 0 | } |
985 | 195k | } |
986 | | |
987 | | |
988 | 205k | static void f_parser (lua_State *L, void *ud) { |
989 | 205k | LClosure *cl; |
990 | 205k | struct SParser *p = cast(struct SParser *, ud); |
991 | 205k | int c = zgetc(p->z); /* read first character */ |
992 | 205k | if (c == LUA_SIGNATURE[0]) { |
993 | 6.32k | checkmode(L, p->mode, "binary"); |
994 | 6.32k | cl = luaU_undump(L, p->z, p->name); |
995 | 6.32k | } |
996 | 198k | else { |
997 | 198k | checkmode(L, p->mode, "text"); |
998 | 198k | cl = luaY_parser(L, p->z, &p->buff, &p->dyd, p->name, c); |
999 | 198k | } |
1000 | 205k | lua_assert(cl->nupvalues == cl->p->sizeupvalues); |
1001 | 205k | luaF_initupvals(L, cl); |
1002 | 205k | } |
1003 | | |
1004 | | |
1005 | | int luaD_protectedparser (lua_State *L, ZIO *z, const char *name, |
1006 | 205k | const char *mode) { |
1007 | 205k | struct SParser p; |
1008 | 205k | int status; |
1009 | 205k | incnny(L); /* cannot yield during parsing */ |
1010 | 205k | p.z = z; p.name = name; p.mode = mode; |
1011 | 205k | p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0; |
1012 | 205k | p.dyd.gt.arr = NULL; p.dyd.gt.size = 0; |
1013 | 205k | p.dyd.label.arr = NULL; p.dyd.label.size = 0; |
1014 | 205k | luaZ_initbuffer(L, &p.buff); |
1015 | 205k | status = luaD_pcall(L, f_parser, &p, savestack(L, L->top.p), L->errfunc); |
1016 | 205k | luaZ_freebuffer(L, &p.buff); |
1017 | 205k | luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size); |
1018 | 205k | luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size); |
1019 | 205k | luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size); |
1020 | 205k | decnny(L); |
1021 | 205k | return status; |
1022 | 205k | } |
1023 | | |
1024 | | |