1 files changed, 417 insertions, 254 deletions

diff --git a/apps/plugins/lua/ldo.c b/apps/plugins/lua/ldo.c
index f303c744c7..e9dd5fa951 100644
--- a/apps/plugins/lua/ldo.c
+++ b/apps/plugins/lua/ldo.c
@@ -1,11 +1,11 @@
 /*
-** $Id: ldo.c,v 2.38.1.3 2008/01/18 22:31:22 roberto Exp $
+** $Id: ldo.c,v 2.108.1.3 2013/11/08 18:22:50 roberto Exp $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
 
 
-/* #include <setjmp.h> */
+#include <setjmp.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -14,6 +14,7 @@
 
 #include "lua.h"
 
+#include "lapi.h"
 #include "ldebug.h"
 #include "ldo.h"
 #include "lfunc.h"
@@ -39,6 +40,38 @@
 ** =======================================================
 */
 
+/*
+** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By
+** default, Lua handles errors with exceptions when compiling as
+** C++ code, with _longjmp/_setjmp when asked to use them, and with
+** longjmp/setjmp otherwise.
+*/
+#if !defined(LUAI_THROW)
+
+#if defined(__cplusplus) && !defined(LUA_USE_LONGJMP)
+/* C++ exceptions */
+#define LUAI_THROW(L,c)         throw(c)
+#define LUAI_TRY(L,c,a) \
+        try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; }
+#define luai_jmpbuf             int  /* dummy variable */
+
+#elif defined(LUA_USE_ULONGJMP)
+/* in Unix, try _longjmp/_setjmp (more efficient) */
+#define LUAI_THROW(L,c)         _longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)         if (_setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf             jmp_buf
+
+#else
+/* default handling with long jumps */
+#define LUAI_THROW(L,c)         longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)         if (setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf             jmp_buf
+
+#endif
+
+#endif
+
+
 
 /* chain list of long jump buffers */
 struct lua_longjmp {
@@ -48,18 +81,17 @@ struct lua_longjmp {
 };
 
 
-void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
   switch (errcode) {
-    case LUA_ERRMEM: {
-      setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG));
+    case LUA_ERRMEM: {  /* memory error? */
+      setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */
       break;
     }
     case LUA_ERRERR: {
       setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
       break;
     }
-    case LUA_ERRSYNTAX:
-    case LUA_ERRRUN: {
+    default: {
       setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
       break;
     }
@@ -68,55 +100,39 @@ void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
 }
 
 
-static void restore_stack_limit (lua_State *L) {
-  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
-  if (L->size_ci > LUAI_MAXCALLS) {  /* there was an overflow? */
-    int inuse = cast_int(L->ci - L->base_ci);
-    if (inuse + 1 < LUAI_MAXCALLS)  /* can `undo' overflow? */
-      luaD_reallocCI(L, LUAI_MAXCALLS);
+l_noret luaD_throw (lua_State *L, int errcode) {
+  if (L->errorJmp) {  /* thread has an error handler? */
+    L->errorJmp->status = errcode;  /* set status */
+    LUAI_THROW(L, L->errorJmp);  /* jump to it */
   }
-}
-
-
-static void resetstack (lua_State *L, int status) {
-  L->ci = L->base_ci;
-  L->base = L->ci->base;
-  luaF_close(L, L->base);  /* close eventual pending closures */
-  luaD_seterrorobj(L, status, L->base);
-  L->nCcalls = L->baseCcalls;
-  L->allowhook = 1;
-  restore_stack_limit(L);
-  L->errfunc = 0;
-  L->errorJmp = NULL;
-}
-
-
-void luaD_throw (lua_State *L, int errcode) {
-  if (L->errorJmp) {
-    L->errorJmp->status = errcode;
-    LUAI_THROW(L, L->errorJmp);
-  }
-  else {
-    L->status = cast_byte(errcode);
-    if (G(L)->panic) {
-      resetstack(L, errcode);
-      lua_unlock(L);
-      G(L)->panic(L);
+  else {  /* thread has no error handler */
+    L->status = cast_byte(errcode);  /* mark it as dead */
+    if (G(L)->mainthread->errorJmp) {  /* main thread has a handler? */
+      setobjs2s(L, G(L)->mainthread->top++, L->top - 1);  /* copy error obj. */
+      luaD_throw(G(L)->mainthread, errcode);  /* re-throw in main thread */
+    }
+    else {  /* no handler at all; abort */
+      if (G(L)->panic) {  /* panic function? */
+        lua_unlock(L);
+        G(L)->panic(L);  /* call it (last chance to jump out) */
+      }
+      abort();
     }
-    exit(EXIT_FAILURE);
   }
 }
 
 
 int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+  unsigned short oldnCcalls = L->nCcalls;
   struct lua_longjmp lj;
-  lj.status = 0;
+  lj.status = LUA_OK;
   lj.previous = L->errorJmp;  /* chain new error handler */
   L->errorJmp = &lj;
   LUAI_TRY(L, &lj,
     (*f)(L, ud);
   );
   L->errorJmp = lj.previous;  /* restore old error handler */
+  L->nCcalls = oldnCcalls;
   return lj.status;
 }
 
@@ -129,112 +145,127 @@ static void correctstack (lua_State *L, TValue *oldstack) {
   L->top = (L->top - oldstack) + L->stack;
   for (up = L->openupval; up != NULL; up = up->gch.next)
     gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack;
-  for (ci = L->base_ci; ci <= L->ci; ci++) {
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
     ci->top = (ci->top - oldstack) + L->stack;
-    ci->base = (ci->base - oldstack) + L->stack;
     ci->func = (ci->func - oldstack) + L->stack;
+    if (isLua(ci))
+      ci->u.l.base = (ci->u.l.base - oldstack) + L->stack;
   }
-  L->base = (L->base - oldstack) + L->stack;
 }
 
 
+/* some space for error handling */
+#define ERRORSTACKSIZE  (LUAI_MAXSTACK + 200)
+
+
 void luaD_reallocstack (lua_State *L, int newsize) {
   TValue *oldstack = L->stack;
-  int realsize = newsize + 1 + EXTRA_STACK;
-  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
-  luaM_reallocvector(L, L->stack, L->stacksize, realsize, TValue);
-  L->stacksize = realsize;
-  L->stack_last = L->stack+newsize;
+  int lim = L->stacksize;
+  lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE);
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK);
+  luaM_reallocvector(L, L->stack, L->stacksize, newsize, TValue);
+  for (; lim < newsize; lim++)
+    setnilvalue(L->stack + lim); /* erase new segment */
+  L->stacksize = newsize;
+  L->stack_last = L->stack + newsize - EXTRA_STACK;
   correctstack(L, oldstack);
 }
 
 
-void luaD_reallocCI (lua_State *L, int newsize) {
-  CallInfo *oldci = L->base_ci;
-  luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo);
-  L->size_ci = newsize;
-  L->ci = (L->ci - oldci) + L->base_ci;
-  L->end_ci = L->base_ci + L->size_ci - 1;
+void luaD_growstack (lua_State *L, int n) {
+  int size = L->stacksize;
+  if (size > LUAI_MAXSTACK)  /* error after extra size? */
+    luaD_throw(L, LUA_ERRERR);
+  else {
+    int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK;
+    int newsize = 2 * size;
+    if (newsize > LUAI_MAXSTACK) newsize = LUAI_MAXSTACK;
+    if (newsize < needed) newsize = needed;
+    if (newsize > LUAI_MAXSTACK) {  /* stack overflow? */
+      luaD_reallocstack(L, ERRORSTACKSIZE);
+      luaG_runerror(L, "stack overflow");
+    }
+    else
+      luaD_reallocstack(L, newsize);
+  }
 }
 
 
-void luaD_growstack (lua_State *L, int n) {
-  if (n <= L->stacksize)  /* double size is enough? */
-    luaD_reallocstack(L, 2*L->stacksize);
-  else
-    luaD_reallocstack(L, L->stacksize + n);
+static int stackinuse (lua_State *L) {
+  CallInfo *ci;
+  StkId lim = L->top;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
+    lua_assert(ci->top <= L->stack_last);
+    if (lim < ci->top) lim = ci->top;
+  }
+  return cast_int(lim - L->stack) + 1;  /* part of stack in use */
 }
 
 
-static CallInfo *growCI (lua_State *L) {
-  if (L->size_ci > LUAI_MAXCALLS)  /* overflow while handling overflow? */
-    luaD_throw(L, LUA_ERRERR);
-  else {
-    luaD_reallocCI(L, 2*L->size_ci);
-    if (L->size_ci > LUAI_MAXCALLS)
-      luaG_runerror(L, "stack overflow");
-  }
-  return ++L->ci;
+void luaD_shrinkstack (lua_State *L) {
+  int inuse = stackinuse(L);
+  int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
+  if (goodsize > LUAI_MAXSTACK) goodsize = LUAI_MAXSTACK;
+  if (inuse > LUAI_MAXSTACK ||  /* handling stack overflow? */
+      goodsize >= L->stacksize)  /* would grow instead of shrink? */
+    condmovestack(L);  /* don't change stack (change only for debugging) */
+  else
+    luaD_reallocstack(L, goodsize);  /* shrink it */
 }
 
 
-void luaD_callhook (lua_State *L, int event, int line) {
+void luaD_hook (lua_State *L, int event, int line) {
   lua_Hook hook = L->hook;
   if (hook && L->allowhook) {
+    CallInfo *ci = L->ci;
     ptrdiff_t top = savestack(L, L->top);
-    ptrdiff_t ci_top = savestack(L, L->ci->top);
+    ptrdiff_t ci_top = savestack(L, ci->top);
     lua_Debug ar;
     ar.event = event;
     ar.currentline = line;
-    if (event == LUA_HOOKTAILRET)
-      ar.i_ci = 0;  /* tail call; no debug information about it */
-    else
-      ar.i_ci = cast_int(L->ci - L->base_ci);
+    ar.i_ci = ci;
     luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
-    L->ci->top = L->top + LUA_MINSTACK;
-    lua_assert(L->ci->top <= L->stack_last);
+    ci->top = L->top + LUA_MINSTACK;
+    lua_assert(ci->top <= L->stack_last);
     L->allowhook = 0;  /* cannot call hooks inside a hook */
+    ci->callstatus |= CIST_HOOKED;
     lua_unlock(L);
     (*hook)(L, &ar);
     lua_lock(L);
     lua_assert(!L->allowhook);
     L->allowhook = 1;
-    L->ci->top = restorestack(L, ci_top);
+    ci->top = restorestack(L, ci_top);
     L->top = restorestack(L, top);
+    ci->callstatus &= ~CIST_HOOKED;
+  }
+}
+
+
+static void callhook (lua_State *L, CallInfo *ci) {
+  int hook = LUA_HOOKCALL;
+  ci->u.l.savedpc++;  /* hooks assume 'pc' is already incremented */
+  if (isLua(ci->previous) &&
+      GET_OPCODE(*(ci->previous->u.l.savedpc - 1)) == OP_TAILCALL) {
+    ci->callstatus |= CIST_TAIL;
+    hook = LUA_HOOKTAILCALL;
   }
+  luaD_hook(L, hook, -1);
+  ci->u.l.savedpc--;  /* correct 'pc' */
 }
 
 
 static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
   int i;
   int nfixargs = p->numparams;
-  Table *htab = NULL;
   StkId base, fixed;
-  for (; actual < nfixargs; ++actual)
-    setnilvalue(L->top++);
-#if defined(LUA_COMPAT_VARARG)
-  if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
-    int nvar = actual - nfixargs;  /* number of extra arguments */
-    lua_assert(p->is_vararg & VARARG_HASARG);
-    luaC_checkGC(L);
-    htab = luaH_new(L, nvar, 1);  /* create `arg' table */
-    for (i=0; i<nvar; i++)  /* put extra arguments into `arg' table */
-      setobj2n(L, luaH_setnum(L, htab, i+1), L->top - nvar + i);
-    /* store counter in field `n' */
-    setnvalue(luaH_setstr(L, htab, luaS_newliteral(L, "n")), cast_num(nvar));
-  }
-#endif
+  lua_assert(actual >= nfixargs);
   /* move fixed parameters to final position */
+  luaD_checkstack(L, p->maxstacksize);  /* check again for new 'base' */
   fixed = L->top - actual;  /* first fixed argument */
   base = L->top;  /* final position of first argument */
   for (i=0; i<nfixargs; i++) {
-    setobjs2s(L, L->top++, fixed+i);
-    setnilvalue(fixed+i);
-  }
-  /* add `arg' parameter */
-  if (htab) {
-    sethvalue(L, L->top++, htab);
-    lua_assert(iswhite(obj2gco(htab)));
+    setobjs2s(L, L->top++, fixed + i);
+    setnilvalue(fixed + i);
   }
   return base;
 }
@@ -256,100 +287,93 @@ static StkId tryfuncTM (lua_State *L, StkId func) {
 
 
 
-#define inc_ci(L) \
-  ((L->ci == L->end_ci) ? growCI(L) : \
-   (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci))
+#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
 
 
+/*
+** returns true if function has been executed (C function)
+*/
 int luaD_precall (lua_State *L, StkId func, int nresults) {
-  LClosure *cl;
-  ptrdiff_t funcr;
-  if (!ttisfunction(func)) /* `func' is not a function? */
-    func = tryfuncTM(L, func);  /* check the `function' tag method */
-  funcr = savestack(L, func);
-  cl = &clvalue(func)->l;
-  L->ci->savedpc = L->savedpc;
-  if (!cl->isC) {  /* Lua function? prepare its call */
-    CallInfo *ci;
-    StkId st, base;
-    Proto *p = cl->p;
-    luaD_checkstack(L, p->maxstacksize);
-    func = restorestack(L, funcr);
-    if (!p->is_vararg) {  /* no varargs? */
-      base = func + 1;
-      if (L->top > base + p->numparams)
-        L->top = base + p->numparams;
-    }
-    else {  /* vararg function */
-      int nargs = cast_int(L->top - func) - 1;
-      base = adjust_varargs(L, p, nargs);
-      func = restorestack(L, funcr);  /* previous call may change the stack */
+  lua_CFunction f;
+  CallInfo *ci;
+  int n;  /* number of arguments (Lua) or returns (C) */
+  ptrdiff_t funcr = savestack(L, func);
+  switch (ttype(func)) {
+    case LUA_TLCF:  /* light C function */
+      f = fvalue(func);
+      goto Cfunc;
+    case LUA_TCCL: {  /* C closure */
+      f = clCvalue(func)->f;
+     Cfunc:
+      luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+      ci = next_ci(L);  /* now 'enter' new function */
+      ci->nresults = nresults;
+      ci->func = restorestack(L, funcr);
+      ci->top = L->top + LUA_MINSTACK;
+      lua_assert(ci->top <= L->stack_last);
+      ci->callstatus = 0;
+      luaC_checkGC(L);  /* stack grow uses memory */
+      if (L->hookmask & LUA_MASKCALL)
+        luaD_hook(L, LUA_HOOKCALL, -1);
+      lua_unlock(L);
+      n = (*f)(L);  /* do the actual call */
+      lua_lock(L);
+      api_checknelems(L, n);
+      luaD_poscall(L, L->top - n);
+      return 1;
     }
-    ci = inc_ci(L);  /* now `enter' new function */
-    ci->func = func;
-    L->base = ci->base = base;
-    ci->top = L->base + p->maxstacksize;
-    lua_assert(ci->top <= L->stack_last);
-    L->savedpc = p->code;  /* starting point */
-    ci->tailcalls = 0;
-    ci->nresults = nresults;
-    for (st = L->top; st < ci->top; st++)
-      setnilvalue(st);
-    L->top = ci->top;
-    if (L->hookmask & LUA_MASKCALL) {
-      L->savedpc++;  /* hooks assume 'pc' is already incremented */
-      luaD_callhook(L, LUA_HOOKCALL, -1);
-      L->savedpc--;  /* correct 'pc' */
+    case LUA_TLCL: {  /* Lua function: prepare its call */
+      StkId base;
+      Proto *p = clLvalue(func)->p;
+      n = cast_int(L->top - func) - 1;  /* number of real arguments */
+      luaD_checkstack(L, p->maxstacksize);
+      for (; n < p->numparams; n++)
+        setnilvalue(L->top++);  /* complete missing arguments */
+      if (!p->is_vararg) {
+        func = restorestack(L, funcr);
+        base = func + 1;
+      }
+      else {
+        base = adjust_varargs(L, p, n);
+        func = restorestack(L, funcr);  /* previous call can change stack */
+      }
+      ci = next_ci(L);  /* now 'enter' new function */
+      ci->nresults = nresults;
+      ci->func = func;
+      ci->u.l.base = base;
+      ci->top = base + p->maxstacksize;
+      lua_assert(ci->top <= L->stack_last);
+      ci->u.l.savedpc = p->code;  /* starting point */
+      ci->callstatus = CIST_LUA;
+      L->top = ci->top;
+      luaC_checkGC(L);  /* stack grow uses memory */
+      if (L->hookmask & LUA_MASKCALL)
+        callhook(L, ci);
+      return 0;
     }
-    return PCRLUA;
-  }
-  else {  /* if is a C function, call it */
-    CallInfo *ci;
-    int n;
-    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
-    ci = inc_ci(L);  /* now `enter' new function */
-    ci->func = restorestack(L, funcr);
-    L->base = ci->base = ci->func + 1;
-    ci->top = L->top + LUA_MINSTACK;
-    lua_assert(ci->top <= L->stack_last);
-    ci->nresults = nresults;
-    if (L->hookmask & LUA_MASKCALL)
-      luaD_callhook(L, LUA_HOOKCALL, -1);
-    lua_unlock(L);
-    n = (*curr_func(L)->c.f)(L);  /* do the actual call */
-    lua_lock(L);
-    if (n < 0)  /* yielding? */
-      return PCRYIELD;
-    else {
-      luaD_poscall(L, L->top - n);
-      return PCRC;
+    default: {  /* not a function */
+      func = tryfuncTM(L, func);  /* retry with 'function' tag method */
+      return luaD_precall(L, func, nresults);  /* now it must be a function */
     }
   }
 }
 
 
-static StkId callrethooks (lua_State *L, StkId firstResult) {
-  ptrdiff_t fr = savestack(L, firstResult);  /* next call may change stack */
-  luaD_callhook(L, LUA_HOOKRET, -1);
-  if (f_isLua(L->ci)) {  /* Lua function? */
-    while ((L->hookmask & LUA_MASKRET) && L->ci->tailcalls--) /* tail calls */
-      luaD_callhook(L, LUA_HOOKTAILRET, -1);
-  }
-  return restorestack(L, fr);
-}
-
-
 int luaD_poscall (lua_State *L, StkId firstResult) {
   StkId res;
   int wanted, i;
-  CallInfo *ci;
-  if (L->hookmask & LUA_MASKRET)
-    firstResult = callrethooks(L, firstResult);
-  ci = L->ci--;
+  CallInfo *ci = L->ci;
+  if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) {
+    if (L->hookmask & LUA_MASKRET) {
+      ptrdiff_t fr = savestack(L, firstResult);  /* hook may change stack */
+      luaD_hook(L, LUA_HOOKRET, -1);
+      firstResult = restorestack(L, fr);
+    }
+    L->oldpc = ci->previous->u.l.savedpc;  /* 'oldpc' for caller function */
+  }
   res = ci->func;  /* res == final position of 1st result */
   wanted = ci->nresults;
-  L->base = (ci - 1)->base;  /* restore base */
-  L->savedpc = (ci - 1)->savedpc;  /* restore savedpc */
+  L->ci = ci = ci->previous;  /* back to caller */
   /* move results to correct place */
   for (i = wanted; i != 0 && firstResult < L->top; i--)
     setobjs2s(L, res++, firstResult++);
@@ -365,112 +389,226 @@ int luaD_poscall (lua_State *L, StkId firstResult) {
 ** The arguments are on the stack, right after the function.
 ** When returns, all the results are on the stack, starting at the original
 ** function position.
-*/ 
-void luaD_call (lua_State *L, StkId func, int nResults) {
+*/
+void luaD_call (lua_State *L, StkId func, int nResults, int allowyield) {
   if (++L->nCcalls >= LUAI_MAXCCALLS) {
     if (L->nCcalls == LUAI_MAXCCALLS)
       luaG_runerror(L, "C stack overflow");
     else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
       luaD_throw(L, LUA_ERRERR);  /* error while handing stack error */
   }
-  if (luaD_precall(L, func, nResults) == PCRLUA)  /* is a Lua function? */
-    luaV_execute(L, 1);  /* call it */
+  if (!allowyield) L->nny++;
+  if (!luaD_precall(L, func, nResults))  /* is a Lua function? */
+    luaV_execute(L);  /* call it */
+  if (!allowyield) L->nny--;
   L->nCcalls--;
-  luaC_checkGC(L);
 }
 
 
-static void resume (lua_State *L, void *ud) {
-  StkId firstArg = cast(StkId, ud);
+static void finishCcall (lua_State *L) {
   CallInfo *ci = L->ci;
-  if (L->status == 0) {  /* start coroutine? */
-    lua_assert(ci == L->base_ci && firstArg > L->base);
-    if (luaD_precall(L, firstArg - 1, LUA_MULTRET) != PCRLUA)
-      return;
+  int n;
+  lua_assert(ci->u.c.k != NULL);  /* must have a continuation */
+  lua_assert(L->nny == 0);
+  if (ci->callstatus & CIST_YPCALL) {  /* was inside a pcall? */
+    ci->callstatus &= ~CIST_YPCALL;  /* finish 'lua_pcall' */
+    L->errfunc = ci->u.c.old_errfunc;
   }
-  else {  /* resuming from previous yield */
-    lua_assert(L->status == LUA_YIELD);
-    L->status = 0;
-    if (!f_isLua(ci)) {  /* `common' yield? */
-      /* finish interrupted execution of `OP_CALL' */
-      lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL ||
-                 GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_TAILCALL);
-      if (luaD_poscall(L, firstArg))  /* complete it... */
-        L->top = L->ci->top;  /* and correct top if not multiple results */
+  /* finish 'lua_callk'/'lua_pcall' */
+  adjustresults(L, ci->nresults);
+  /* call continuation function */
+  if (!(ci->callstatus & CIST_STAT))  /* no call status? */
+    ci->u.c.status = LUA_YIELD;  /* 'default' status */
+  lua_assert(ci->u.c.status != LUA_OK);
+  ci->callstatus = (ci->callstatus & ~(CIST_YPCALL | CIST_STAT)) | CIST_YIELDED;
+  lua_unlock(L);
+  n = (*ci->u.c.k)(L);
+  lua_lock(L);
+  api_checknelems(L, n);
+  /* finish 'luaD_precall' */
+  luaD_poscall(L, L->top - n);
+}
+
+
+static void unroll (lua_State *L, void *ud) {
+  UNUSED(ud);
+  for (;;) {
+    if (L->ci == &L->base_ci)  /* stack is empty? */
+      return;  /* coroutine finished normally */
+    if (!isLua(L->ci))  /* C function? */
+      finishCcall(L);
+    else {  /* Lua function */
+      luaV_finishOp(L);  /* finish interrupted instruction */
+      luaV_execute(L);  /* execute down to higher C 'boundary' */
     }
-    else  /* yielded inside a hook: just continue its execution */
-      L->base = L->ci->base;
   }
-  luaV_execute(L, cast_int(L->ci - L->base_ci));
 }
 
 
-static int resume_error (lua_State *L, const char *msg) {
-  L->top = L->ci->base;
-  setsvalue2s(L, L->top, luaS_new(L, msg));
-  incr_top(L);
-  lua_unlock(L);
-  return LUA_ERRRUN;
+/*
+** check whether thread has a suspended protected call
+*/
+static CallInfo *findpcall (lua_State *L) {
+  CallInfo *ci;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {  /* search for a pcall */
+    if (ci->callstatus & CIST_YPCALL)
+      return ci;
+  }
+  return NULL;  /* no pending pcall */
+}
+
+
+static int recover (lua_State *L, int status) {
+  StkId oldtop;
+  CallInfo *ci = findpcall(L);
+  if (ci == NULL) return 0;  /* no recovery point */
+  /* "finish" luaD_pcall */
+  oldtop = restorestack(L, ci->extra);
+  luaF_close(L, oldtop);
+  seterrorobj(L, status, oldtop);
+  L->ci = ci;
+  L->allowhook = ci->u.c.old_allowhook;
+  L->nny = 0;  /* should be zero to be yieldable */
+  luaD_shrinkstack(L);
+  L->errfunc = ci->u.c.old_errfunc;
+  ci->callstatus |= CIST_STAT;  /* call has error status */
+  ci->u.c.status = status;  /* (here it is) */
+  return 1;  /* continue running the coroutine */
+}
+
+
+/*
+** signal an error in the call to 'resume', not in the execution of the
+** coroutine itself. (Such errors should not be handled by any coroutine
+** error handler and should not kill the coroutine.)
+*/
+static l_noret resume_error (lua_State *L, const char *msg, StkId firstArg) {
+  L->top = firstArg;  /* remove args from the stack */
+  setsvalue2s(L, L->top, luaS_new(L, msg));  /* push error message */
+  api_incr_top(L);
+  luaD_throw(L, -1);  /* jump back to 'lua_resume' */
 }
 
 
-LUA_API int lua_resume (lua_State *L, int nargs) {
+/*
+** do the work for 'lua_resume' in protected mode
+*/
+static void resume (lua_State *L, void *ud) {
+  int nCcalls = L->nCcalls;
+  StkId firstArg = cast(StkId, ud);
+  CallInfo *ci = L->ci;
+  if (nCcalls >= LUAI_MAXCCALLS)
+    resume_error(L, "C stack overflow", firstArg);
+  if (L->status == LUA_OK) {  /* may be starting a coroutine */
+    if (ci != &L->base_ci)  /* not in base level? */
+      resume_error(L, "cannot resume non-suspended coroutine", firstArg);
+    /* coroutine is in base level; start running it */
+    if (!luaD_precall(L, firstArg - 1, LUA_MULTRET))  /* Lua function? */
+      luaV_execute(L);  /* call it */
+  }
+  else if (L->status != LUA_YIELD)
+    resume_error(L, "cannot resume dead coroutine", firstArg);
+  else {  /* resuming from previous yield */
+    L->status = LUA_OK;
+    ci->func = restorestack(L, ci->extra);
+    if (isLua(ci))  /* yielded inside a hook? */
+      luaV_execute(L);  /* just continue running Lua code */
+    else {  /* 'common' yield */
+      if (ci->u.c.k != NULL) {  /* does it have a continuation? */
+        int n;
+        ci->u.c.status = LUA_YIELD;  /* 'default' status */
+        ci->callstatus |= CIST_YIELDED;
+        lua_unlock(L);
+        n = (*ci->u.c.k)(L);  /* call continuation */
+        lua_lock(L);
+        api_checknelems(L, n);
+        firstArg = L->top - n;  /* yield results come from continuation */
+      }
+      luaD_poscall(L, firstArg);  /* finish 'luaD_precall' */
+    }
+    unroll(L, NULL);
+  }
+  lua_assert(nCcalls == L->nCcalls);
+}
+
+
+LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs) {
   int status;
+  int oldnny = L->nny;  /* save 'nny' */
   lua_lock(L);
-  if (L->status != LUA_YIELD && (L->status != 0 || L->ci != L->base_ci))
-      return resume_error(L, "cannot resume non-suspended coroutine");
-  if (L->nCcalls >= LUAI_MAXCCALLS)
-    return resume_error(L, "C stack overflow");
   luai_userstateresume(L, nargs);
-  lua_assert(L->errfunc == 0);
-  L->baseCcalls = ++L->nCcalls;
+  L->nCcalls = (from) ? from->nCcalls + 1 : 1;
+  L->nny = 0;  /* allow yields */
+  api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs);
   status = luaD_rawrunprotected(L, resume, L->top - nargs);
-  if (status != 0) {  /* error? */
-    L->status = cast_byte(status);  /* mark thread as `dead' */
-    luaD_seterrorobj(L, status, L->top);
-    L->ci->top = L->top;
-  }
-  else {
-    lua_assert(L->nCcalls == L->baseCcalls);
-    status = L->status;
+  if (status == -1)  /* error calling 'lua_resume'? */
+    status = LUA_ERRRUN;
+  else {  /* yield or regular error */
+    while (status != LUA_OK && status != LUA_YIELD) {  /* error? */
+      if (recover(L, status))  /* recover point? */
+        status = luaD_rawrunprotected(L, unroll, NULL);  /* run continuation */
+      else {  /* unrecoverable error */
+        L->status = cast_byte(status);  /* mark thread as `dead' */
+        seterrorobj(L, status, L->top);
+        L->ci->top = L->top;
+        break;
+      }
+    }
+    lua_assert(status == L->status);
   }
-  --L->nCcalls;
+  L->nny = oldnny;  /* restore 'nny' */
+  L->nCcalls--;
+  lua_assert(L->nCcalls == ((from) ? from->nCcalls : 0));
   lua_unlock(L);
   return status;
 }
 
 
-LUA_API int lua_yield (lua_State *L, int nresults) {
+LUA_API int lua_yieldk (lua_State *L, int nresults, int ctx, lua_CFunction k) {
+  CallInfo *ci = L->ci;
   luai_userstateyield(L, nresults);
   lua_lock(L);
-  if (L->nCcalls > L->baseCcalls)
-    luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
-  L->base = L->top - nresults;  /* protect stack slots below */
+  api_checknelems(L, nresults);
+  if (L->nny > 0) {
+    if (L != G(L)->mainthread)
+      luaG_runerror(L, "attempt to yield across a C-call boundary");
+    else
+      luaG_runerror(L, "attempt to yield from outside a coroutine");
+  }
   L->status = LUA_YIELD;
+  ci->extra = savestack(L, ci->func);  /* save current 'func' */
+  if (isLua(ci)) {  /* inside a hook? */
+    api_check(L, k == NULL, "hooks cannot continue after yielding");
+  }
+  else {
+    if ((ci->u.c.k = k) != NULL)  /* is there a continuation? */
+      ci->u.c.ctx = ctx;  /* save context */
+    ci->func = L->top - nresults - 1;  /* protect stack below results */
+    luaD_throw(L, LUA_YIELD);
+  }
+  lua_assert(ci->callstatus & CIST_HOOKED);  /* must be inside a hook */
   lua_unlock(L);
-  return -1;
+  return 0;  /* return to 'luaD_hook' */
 }
 
 
 int luaD_pcall (lua_State *L, Pfunc func, void *u,
                 ptrdiff_t old_top, ptrdiff_t ef) {
   int status;
-  unsigned short oldnCcalls = L->nCcalls;
-  ptrdiff_t old_ci = saveci(L, L->ci);
+  CallInfo *old_ci = L->ci;
   lu_byte old_allowhooks = L->allowhook;
+  unsigned short old_nny = L->nny;
   ptrdiff_t old_errfunc = L->errfunc;
   L->errfunc = ef;
   status = luaD_rawrunprotected(L, func, u);
-  if (status != 0) {  /* an error occurred? */
+  if (status != LUA_OK) {  /* an error occurred? */
     StkId oldtop = restorestack(L, old_top);
-    luaF_close(L, oldtop);  /* close eventual pending closures */
-    luaD_seterrorobj(L, status, oldtop);
-    L->nCcalls = oldnCcalls;
-    L->ci = restoreci(L, old_ci);
-    L->base = L->ci->base;
-    L->savedpc = L->ci->savedpc;
+    luaF_close(L, oldtop);  /* close possible pending closures */
+    seterrorobj(L, status, oldtop);
+    L->ci = old_ci;
     L->allowhook = old_allowhooks;
-    restore_stack_limit(L);
+    L->nny = old_nny;
+    luaD_shrinkstack(L);
   }
   L->errfunc = old_errfunc;
   return status;
@@ -483,35 +621,60 @@ int luaD_pcall (lua_State *L, Pfunc func, void *u,
 */
 struct SParser {  /* data to `f_parser' */
   ZIO *z;
-  Mbuffer buff;  /* buffer to be used by the scanner */
+  Mbuffer buff;  /* dynamic structure used by the scanner */
+  Dyndata dyd;  /* dynamic structures used by the parser */
+  const char *mode;
   const char *name;
 };
 
+
+static void checkmode (lua_State *L, const char *mode, const char *x) {
+  if (mode && strchr(mode, x[0]) == NULL) {
+    luaO_pushfstring(L,
+       "attempt to load a %s chunk (mode is " LUA_QS ")", x, mode);
+    luaD_throw(L, LUA_ERRSYNTAX);
+  }
+}
+
+
 static void f_parser (lua_State *L, void *ud) {
   int i;
-  Proto *tf;
   Closure *cl;
   struct SParser *p = cast(struct SParser *, ud);
-  int c = luaZ_lookahead(p->z);
-  luaC_checkGC(L);
-  tf = ((c == LUA_SIGNATURE[0]) ? luaU_undump : luaY_parser)(L, p->z,
-                                                             &p->buff, p->name);
-  cl = luaF_newLclosure(L, tf->nups, hvalue(gt(L)));
-  cl->l.p = tf;
-  for (i = 0; i < tf->nups; i++)  /* initialize eventual upvalues */
-    cl->l.upvals[i] = luaF_newupval(L);
-  setclvalue(L, L->top, cl);
-  incr_top(L);
+  int c = zgetc(p->z);  /* read first character */
+  if (c == LUA_SIGNATURE[0]) {
+    checkmode(L, p->mode, "binary");
+    cl = luaU_undump(L, p->z, &p->buff, p->name);
+  }
+  else {
+    checkmode(L, p->mode, "text");
+    cl = luaY_parser(L, p->z, &p->buff, &p->dyd, p->name, c);
+  }
+  lua_assert(cl->l.nupvalues == cl->l.p->sizeupvalues);
+  for (i = 0; i < cl->l.nupvalues; i++) {  /* initialize upvalues */
+    UpVal *up = luaF_newupval(L);
+    cl->l.upvals[i] = up;
+    luaC_objbarrier(L, cl, up);
+  }
 }
 
 
-int luaD_protectedparser (lua_State *L, ZIO *z, const char *name) {
+int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
+                                        const char *mode) {
   struct SParser p;
   int status;
-  p.z = z; p.name = name;
+  L->nny++;  /* cannot yield during parsing */
+  p.z = z; p.name = name; p.mode = mode;
+  p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0;
+  p.dyd.gt.arr = NULL; p.dyd.gt.size = 0;
+  p.dyd.label.arr = NULL; p.dyd.label.size = 0;
   luaZ_initbuffer(L, &p.buff);
   status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
   luaZ_freebuffer(L, &p.buff);
+  luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size);
+  luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size);
+  luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size);
+  L->nny--;
   return status;
 }