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Diffstat (limited to 'lib/lua/src/ldo.c')
-rw-r--r--lib/lua/src/ldo.c930
1 files changed, 465 insertions, 465 deletions
diff --git a/lib/lua/src/ldo.c b/lib/lua/src/ldo.c
index 44bba83..8c64852 100644
--- a/lib/lua/src/ldo.c
+++ b/lib/lua/src/ldo.c
@@ -1,465 +1,465 @@
-/*
-** $Id: ldo.c,v 1.3 2004-07-23 13:08:23 pixel Exp $
-** Stack and Call structure of Lua
-** See Copyright Notice in lua.h
-*/
-
-
-#include <setjmp.h>
-#include <stdlib.h>
-#include <string.h>
-
-#define ldo_c
-
-#include "lua.h"
-
-#include "ldebug.h"
-#include "ldo.h"
-#include "lfunc.h"
-#include "lgc.h"
-#include "lmem.h"
-#include "lobject.h"
-#include "lopcodes.h"
-#include "lparser.h"
-#include "lstate.h"
-#include "lstring.h"
-#include "ltable.h"
-#include "ltm.h"
-#include "lundump.h"
-#include "lvm.h"
-#include "lzio.h"
-
-
-
-
-/*
-** {======================================================
-** Error-recovery functions (based on long jumps)
-** =======================================================
-*/
-
-
-/* chain list of long jump buffers */
-struct lua_longjmp {
- struct lua_longjmp *previous;
- jmp_buf b;
- volatile int status; /* error code */
-};
-
-
-static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
- switch (errcode) {
- case LUA_ERRMEM: {
- setsvalue2s(oldtop, luaS_new(L, MEMERRMSG));
- break;
- }
- case LUA_ERRERR: {
- setsvalue2s(oldtop, luaS_new(L, "error in error handling"));
- break;
- }
- case LUA_ERRSYNTAX:
- case LUA_ERRRUN: {
- setobjs2s(oldtop, L->top - 1); /* error message on current top */
- break;
- }
- }
- L->top = oldtop + 1;
-}
-
-
-void luaD_throw (lua_State *L, int errcode) {
- if (L->errorJmp) {
- L->errorJmp->status = errcode;
- longjmp(L->errorJmp->b, 1);
- }
- else {
- G(L)->panic(L);
- exit(EXIT_FAILURE);
- }
-}
-
-
-int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
- struct lua_longjmp lj;
- lj.status = 0;
- lj.previous = L->errorJmp; /* chain new error handler */
- L->errorJmp = &lj;
- if (setjmp(lj.b) == 0)
- (*f)(L, ud);
- L->errorJmp = lj.previous; /* restore old error handler */
- return lj.status;
-}
-
-
-static void restore_stack_limit (lua_State *L) {
- L->stack_last = L->stack+L->stacksize-1;
- if (L->size_ci > LUA_MAXCALLS) { /* there was an overflow? */
- int inuse = (L->ci - L->base_ci);
- if (inuse + 1 < LUA_MAXCALLS) /* can `undo' overflow? */
- luaD_reallocCI(L, LUA_MAXCALLS);
- }
-}
-
-/* }====================================================== */
-
-
-static void correctstack (lua_State *L, TObject *oldstack) {
- CallInfo *ci;
- GCObject *up;
- L->top = (L->top - oldstack) + L->stack;
- for (up = L->openupval; up != NULL; up = up->gch.next)
- gcotouv(up)->v = (gcotouv(up)->v - oldstack) + L->stack;
- for (ci = L->base_ci; ci <= L->ci; ci++) {
- ci->top = (ci->top - oldstack) + L->stack;
- ci->base = (ci->base - oldstack) + L->stack;
- }
- L->base = L->ci->base;
-}
-
-
-void luaD_reallocstack (lua_State *L, int newsize) {
- TObject *oldstack = L->stack;
- luaM_reallocvector(L, L->stack, L->stacksize, newsize, TObject);
- L->stacksize = newsize;
- L->stack_last = L->stack+newsize-1-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 = cast(unsigned short, newsize);
- L->ci = (L->ci - oldci) + L->base_ci;
- L->end_ci = L->base_ci + L->size_ci;
-}
-
-
-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 + EXTRA_STACK);
-}
-
-
-static void luaD_growCI (lua_State *L) {
- if (L->size_ci > LUA_MAXCALLS) /* overflow while handling overflow? */
- luaD_throw(L, LUA_ERRERR);
- else {
- luaD_reallocCI(L, 2*L->size_ci);
- if (L->size_ci > LUA_MAXCALLS)
- luaG_runerror(L, "stack overflow");
- }
-}
-
-
-void luaD_callhook (lua_State *L, int event, int line) {
- lua_Hook hook = L->hook;
- if (hook && L->allowhook) {
- ptrdiff_t top = savestack(L, L->top);
- ptrdiff_t ci_top = savestack(L, 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 = L->ci - L->base_ci;
- luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
- L->ci->top = L->top + LUA_MINSTACK;
- L->allowhook = 0; /* cannot call hooks inside a hook */
- lua_unlock(L);
- (*hook)(L, &ar);
- lua_lock(L);
- lua_assert(!L->allowhook);
- L->allowhook = 1;
- L->ci->top = restorestack(L, ci_top);
- L->top = restorestack(L, top);
- }
-}
-
-
-static void adjust_varargs (lua_State *L, int nfixargs, StkId base) {
- int i;
- Table *htab;
- TObject nname;
- int actual = L->top - base; /* actual number of arguments */
- if (actual < nfixargs) {
- luaD_checkstack(L, nfixargs - actual);
- for (; actual < nfixargs; ++actual)
- setnilvalue(L->top++);
- }
- actual -= nfixargs; /* number of extra arguments */
- htab = luaH_new(L, actual, 1); /* create `arg' table */
- for (i=0; i<actual; i++) /* put extra arguments into `arg' table */
- setobj2n(luaH_setnum(L, htab, i+1), L->top - actual + i);
- /* store counter in field `n' */
- setsvalue(&nname, luaS_newliteral(L, "n"));
- setnvalue(luaH_set(L, htab, &nname), cast(lua_Number, actual));
- L->top -= actual; /* remove extra elements from the stack */
- sethvalue(L->top, htab);
- incr_top(L);
-}
-
-
-static StkId tryfuncTM (lua_State *L, StkId func) {
- const TObject *tm = luaT_gettmbyobj(L, func, TM_CALL);
- StkId p;
- ptrdiff_t funcr = savestack(L, func);
- if (!ttisfunction(tm))
- luaG_typeerror(L, func, "call");
- /* Open a hole inside the stack at `func' */
- for (p = L->top; p > func; p--) setobjs2s(p, p-1);
- incr_top(L);
- func = restorestack(L, funcr); /* previous call may change stack */
- setobj2s(func, tm); /* tag method is the new function to be called */
- return func;
-}
-
-
-StkId luaD_precall (lua_State *L, StkId func) {
- LClosure *cl;
- ptrdiff_t funcr = savestack(L, func);
- if (!ttisfunction(func)) /* `func' is not a function? */
- func = tryfuncTM(L, func); /* check the `function' tag method */
- if (L->ci + 1 == L->end_ci) luaD_growCI(L);
- else condhardstacktests(luaD_reallocCI(L, L->size_ci));
- cl = &clvalue(func)->l;
- if (!cl->isC) { /* Lua function? prepare its call */
- CallInfo *ci;
- Proto *p = cl->p;
- if (p->is_vararg) /* varargs? */
- adjust_varargs(L, p->numparams, func+1);
- luaD_checkstack(L, p->maxstacksize);
- ci = ++L->ci; /* now `enter' new function */
- L->base = L->ci->base = restorestack(L, funcr) + 1;
- ci->top = L->base + p->maxstacksize;
- ci->u.l.savedpc = p->code; /* starting point */
- ci->u.l.tailcalls = 0;
- ci->state = CI_SAVEDPC;
- while (L->top < ci->top)
- setnilvalue(L->top++);
- L->top = ci->top;
- return NULL;
- }
- else { /* if is a C function, call it */
- CallInfo *ci;
- int n;
- luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
- ci = ++L->ci; /* now `enter' new function */
- L->base = L->ci->base = restorestack(L, funcr) + 1;
- ci->top = L->top + LUA_MINSTACK;
- ci->state = CI_C; /* a C function */
- if (L->hookmask & LUA_MASKCALL)
- luaD_callhook(L, LUA_HOOKCALL, -1);
- lua_unlock(L);
-#ifdef LUA_COMPATUPVALUES
- lua_pushupvalues(L);
-#endif
- n = (*clvalue(L->base - 1)->c.f)(L); /* do the actual call */
- lua_lock(L);
- return L->top - n;
- }
-}
-
-
-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 (!(L->ci->state & CI_C)) { /* Lua function? */
- while (L->ci->u.l.tailcalls--) /* call hook for eventual tail calls */
- luaD_callhook(L, LUA_HOOKTAILRET, -1);
- }
- return restorestack(L, fr);
-}
-
-
-void luaD_poscall (lua_State *L, int wanted, StkId firstResult) {
- StkId res;
- if (L->hookmask & LUA_MASKRET)
- firstResult = callrethooks(L, firstResult);
- res = L->base - 1; /* res == final position of 1st result */
- L->ci--;
- L->base = L->ci->base; /* restore base */
- /* move results to correct place */
- while (wanted != 0 && firstResult < L->top) {
- setobjs2s(res++, firstResult++);
- wanted--;
- }
- while (wanted-- > 0)
- setnilvalue(res++);
- L->top = res;
-}
-
-
-/*
-** Call a function (C or Lua). The function to be called is at *func.
-** 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) {
- StkId firstResult;
- lua_assert(!(L->ci->state & CI_CALLING));
- if (++L->nCcalls >= LUA_MAXCCALLS) {
- if (L->nCcalls == LUA_MAXCCALLS)
- luaG_runerror(L, "C stack overflow");
- else if (L->nCcalls >= (LUA_MAXCCALLS + (LUA_MAXCCALLS>>3)))
- luaD_throw(L, LUA_ERRERR); /* error while handing stack error */
- }
- firstResult = luaD_precall(L, func);
- if (firstResult == NULL) /* is a Lua function? */
- firstResult = luaV_execute(L); /* call it */
- luaD_poscall(L, nResults, firstResult);
- L->nCcalls--;
- luaC_checkGC(L);
-}
-
-
-static void resume (lua_State *L, void *ud) {
- StkId firstResult;
- int nargs = *cast(int *, ud);
- CallInfo *ci = L->ci;
- if (ci == L->base_ci) { /* no activation record? */
- if (nargs >= L->top - L->base)
- luaG_runerror(L, "cannot resume dead coroutine");
- luaD_precall(L, L->top - (nargs + 1)); /* start coroutine */
- }
- else if (ci->state & CI_YIELD) { /* inside a yield? */
- if (ci->state & CI_C) { /* `common' yield? */
- /* finish interrupted execution of `OP_CALL' */
- int nresults;
- lua_assert((ci-1)->state & CI_SAVEDPC);
- lua_assert(GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_CALL ||
- GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_TAILCALL);
- nresults = GETARG_C(*((ci-1)->u.l.savedpc - 1)) - 1;
- luaD_poscall(L, nresults, L->top - nargs); /* complete it */
- if (nresults >= 0) L->top = L->ci->top;
- }
- else { /* yielded inside a hook: just continue its execution */
- ci->state &= ~CI_YIELD;
- }
- }
- else
- luaG_runerror(L, "cannot resume non-suspended coroutine");
- firstResult = luaV_execute(L);
- if (firstResult != NULL) /* return? */
- luaD_poscall(L, LUA_MULTRET, firstResult); /* finalize this coroutine */
-}
-
-
-LUA_API int lua_resume (lua_State *L, int nargs) {
- int status;
- lu_byte old_allowhooks;
- lua_lock(L);
- old_allowhooks = L->allowhook;
- lua_assert(L->errfunc == 0 && L->nCcalls == 0);
- status = luaD_rawrunprotected(L, resume, &nargs);
- if (status != 0) { /* error? */
- L->ci = L->base_ci; /* go back to initial level */
- L->base = L->ci->base;
- L->nCcalls = 0;
- luaF_close(L, L->base); /* close eventual pending closures */
- seterrorobj(L, status, L->base);
- L->allowhook = old_allowhooks;
- restore_stack_limit(L);
- }
- lua_unlock(L);
- return status;
-}
-
-
-LUA_API int lua_yield (lua_State *L, int nresults) {
- CallInfo *ci;
- lua_lock(L);
- ci = L->ci;
- if (L->nCcalls > 0)
- luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
- if (ci->state & CI_C) { /* usual yield */
- if ((ci-1)->state & CI_C)
- luaG_runerror(L, "cannot yield a C function");
- if (L->top - nresults > L->base) { /* is there garbage in the stack? */
- int i;
- for (i=0; i<nresults; i++) /* move down results */
- setobjs2s(L->base + i, L->top - nresults + i);
- L->top = L->base + nresults;
- }
- } /* else it's an yield inside a hook: nothing to do */
- ci->state |= CI_YIELD;
- lua_unlock(L);
- return -1;
-}
-
-LUA_API void lua_break (lua_State *L) {
- CallInfo * ci;
- lua_lock(L);
- ci = L->ci;
- ci->state |= CI_BREAK;
- lua_unlock(L);
-}
-
-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);
- lu_byte old_allowhooks = L->allowhook;
- ptrdiff_t old_errfunc = L->errfunc;
- L->errfunc = ef;
- status = luaD_rawrunprotected(L, func, u);
- if (status != 0) { /* an error occurred? */
- StkId oldtop = restorestack(L, old_top);
- luaF_close(L, oldtop); /* close eventual pending closures */
- seterrorobj(L, status, oldtop);
- L->nCcalls = oldnCcalls;
- L->ci = restoreci(L, old_ci);
- L->base = L->ci->base;
- L->allowhook = old_allowhooks;
- restore_stack_limit(L);
- }
- L->errfunc = old_errfunc;
- return status;
-}
-
-
-
-/*
-** Execute a protected parser.
-*/
-struct SParser { /* data to `f_parser' */
- ZIO *z;
- Mbuffer buff; /* buffer to be used by the scanner */
- int bin;
-};
-
-static void f_parser (lua_State *L, void *ud) {
- struct SParser *p;
- Proto *tf;
- Closure *cl;
- luaC_checkGC(L);
- p = cast(struct SParser *, ud);
- tf = p->bin ? luaU_undump(L, p->z, &p->buff) : luaY_parser(L, p->z, &p->buff);
- cl = luaF_newLclosure(L, 0, gt(L));
- cl->l.p = tf;
- setclvalue(L->top, cl);
- incr_top(L);
-}
-
-
-int luaD_protectedparser (lua_State *L, ZIO *z, int bin) {
- struct SParser p;
- int status;
- ptrdiff_t oldtopr = savestack(L, L->top); /* save current top */
- p.z = z; p.bin = bin;
- luaZ_initbuffer(L, &p.buff);
- status = luaD_rawrunprotected(L, f_parser, &p);
- luaZ_freebuffer(L, &p.buff);
- if (status != 0) { /* error? */
- StkId oldtop = restorestack(L, oldtopr);
- seterrorobj(L, status, oldtop);
- }
- return status;
-}
-
-
+/*
+** $Id: ldo.c,v 1.4 2004-11-27 21:35:20 pixel Exp $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldo_c
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+#include "lzio.h"
+
+
+
+
+/*
+** {======================================================
+** Error-recovery functions (based on long jumps)
+** =======================================================
+*/
+
+
+/* chain list of long jump buffers */
+struct lua_longjmp {
+ struct lua_longjmp *previous;
+ jmp_buf b;
+ volatile int status; /* error code */
+};
+
+
+static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+ switch (errcode) {
+ case LUA_ERRMEM: {
+ setsvalue2s(oldtop, luaS_new(L, MEMERRMSG));
+ break;
+ }
+ case LUA_ERRERR: {
+ setsvalue2s(oldtop, luaS_new(L, "error in error handling"));
+ break;
+ }
+ case LUA_ERRSYNTAX:
+ case LUA_ERRRUN: {
+ setobjs2s(oldtop, L->top - 1); /* error message on current top */
+ break;
+ }
+ }
+ L->top = oldtop + 1;
+}
+
+
+void luaD_throw (lua_State *L, int errcode) {
+ if (L->errorJmp) {
+ L->errorJmp->status = errcode;
+ longjmp(L->errorJmp->b, 1);
+ }
+ else {
+ G(L)->panic(L);
+ exit(EXIT_FAILURE);
+ }
+}
+
+
+int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+ struct lua_longjmp lj;
+ lj.status = 0;
+ lj.previous = L->errorJmp; /* chain new error handler */
+ L->errorJmp = &lj;
+ if (setjmp(lj.b) == 0)
+ (*f)(L, ud);
+ L->errorJmp = lj.previous; /* restore old error handler */
+ return lj.status;
+}
+
+
+static void restore_stack_limit (lua_State *L) {
+ L->stack_last = L->stack+L->stacksize-1;
+ if (L->size_ci > LUA_MAXCALLS) { /* there was an overflow? */
+ int inuse = (L->ci - L->base_ci);
+ if (inuse + 1 < LUA_MAXCALLS) /* can `undo' overflow? */
+ luaD_reallocCI(L, LUA_MAXCALLS);
+ }
+}
+
+/* }====================================================== */
+
+
+static void correctstack (lua_State *L, TObject *oldstack) {
+ CallInfo *ci;
+ GCObject *up;
+ L->top = (L->top - oldstack) + L->stack;
+ for (up = L->openupval; up != NULL; up = up->gch.next)
+ gcotouv(up)->v = (gcotouv(up)->v - oldstack) + L->stack;
+ for (ci = L->base_ci; ci <= L->ci; ci++) {
+ ci->top = (ci->top - oldstack) + L->stack;
+ ci->base = (ci->base - oldstack) + L->stack;
+ }
+ L->base = L->ci->base;
+}
+
+
+void luaD_reallocstack (lua_State *L, int newsize) {
+ TObject *oldstack = L->stack;
+ luaM_reallocvector(L, L->stack, L->stacksize, newsize, TObject);
+ L->stacksize = newsize;
+ L->stack_last = L->stack+newsize-1-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 = cast(unsigned short, newsize);
+ L->ci = (L->ci - oldci) + L->base_ci;
+ L->end_ci = L->base_ci + L->size_ci;
+}
+
+
+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 + EXTRA_STACK);
+}
+
+
+static void luaD_growCI (lua_State *L) {
+ if (L->size_ci > LUA_MAXCALLS) /* overflow while handling overflow? */
+ luaD_throw(L, LUA_ERRERR);
+ else {
+ luaD_reallocCI(L, 2*L->size_ci);
+ if (L->size_ci > LUA_MAXCALLS)
+ luaG_runerror(L, "stack overflow");
+ }
+}
+
+
+void luaD_callhook (lua_State *L, int event, int line) {
+ lua_Hook hook = L->hook;
+ if (hook && L->allowhook) {
+ ptrdiff_t top = savestack(L, L->top);
+ ptrdiff_t ci_top = savestack(L, 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 = L->ci - L->base_ci;
+ luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
+ L->ci->top = L->top + LUA_MINSTACK;
+ L->allowhook = 0; /* cannot call hooks inside a hook */
+ lua_unlock(L);
+ (*hook)(L, &ar);
+ lua_lock(L);
+ lua_assert(!L->allowhook);
+ L->allowhook = 1;
+ L->ci->top = restorestack(L, ci_top);
+ L->top = restorestack(L, top);
+ }
+}
+
+
+static void adjust_varargs (lua_State *L, int nfixargs, StkId base) {
+ int i;
+ Table *htab;
+ TObject nname;
+ int actual = L->top - base; /* actual number of arguments */
+ if (actual < nfixargs) {
+ luaD_checkstack(L, nfixargs - actual);
+ for (; actual < nfixargs; ++actual)
+ setnilvalue(L->top++);
+ }
+ actual -= nfixargs; /* number of extra arguments */
+ htab = luaH_new(L, actual, 1); /* create `arg' table */
+ for (i=0; i<actual; i++) /* put extra arguments into `arg' table */
+ setobj2n(luaH_setnum(L, htab, i+1), L->top - actual + i);
+ /* store counter in field `n' */
+ setsvalue(&nname, luaS_newliteral(L, "n"));
+ setnvalue(luaH_set(L, htab, &nname), cast(lua_Number, actual));
+ L->top -= actual; /* remove extra elements from the stack */
+ sethvalue(L->top, htab);
+ incr_top(L);
+}
+
+
+static StkId tryfuncTM (lua_State *L, StkId func) {
+ const TObject *tm = luaT_gettmbyobj(L, func, TM_CALL);
+ StkId p;
+ ptrdiff_t funcr = savestack(L, func);
+ if (!ttisfunction(tm))
+ luaG_typeerror(L, func, "call");
+ /* Open a hole inside the stack at `func' */
+ for (p = L->top; p > func; p--) setobjs2s(p, p-1);
+ incr_top(L);
+ func = restorestack(L, funcr); /* previous call may change stack */
+ setobj2s(func, tm); /* tag method is the new function to be called */
+ return func;
+}
+
+
+StkId luaD_precall (lua_State *L, StkId func) {
+ LClosure *cl;
+ ptrdiff_t funcr = savestack(L, func);
+ if (!ttisfunction(func)) /* `func' is not a function? */
+ func = tryfuncTM(L, func); /* check the `function' tag method */
+ if (L->ci + 1 == L->end_ci) luaD_growCI(L);
+ else condhardstacktests(luaD_reallocCI(L, L->size_ci));
+ cl = &clvalue(func)->l;
+ if (!cl->isC) { /* Lua function? prepare its call */
+ CallInfo *ci;
+ Proto *p = cl->p;
+ if (p->is_vararg) /* varargs? */
+ adjust_varargs(L, p->numparams, func+1);
+ luaD_checkstack(L, p->maxstacksize);
+ ci = ++L->ci; /* now `enter' new function */
+ L->base = L->ci->base = restorestack(L, funcr) + 1;
+ ci->top = L->base + p->maxstacksize;
+ ci->u.l.savedpc = p->code; /* starting point */
+ ci->u.l.tailcalls = 0;
+ ci->state = CI_SAVEDPC;
+ while (L->top < ci->top)
+ setnilvalue(L->top++);
+ L->top = ci->top;
+ return NULL;
+ }
+ else { /* if is a C function, call it */
+ CallInfo *ci;
+ int n;
+ luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
+ ci = ++L->ci; /* now `enter' new function */
+ L->base = L->ci->base = restorestack(L, funcr) + 1;
+ ci->top = L->top + LUA_MINSTACK;
+ ci->state = CI_C; /* a C function */
+ if (L->hookmask & LUA_MASKCALL)
+ luaD_callhook(L, LUA_HOOKCALL, -1);
+ lua_unlock(L);
+#ifdef LUA_COMPATUPVALUES
+ lua_pushupvalues(L);
+#endif
+ n = (*clvalue(L->base - 1)->c.f)(L); /* do the actual call */
+ lua_lock(L);
+ return L->top - n;
+ }
+}
+
+
+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 (!(L->ci->state & CI_C)) { /* Lua function? */
+ while (L->ci->u.l.tailcalls--) /* call hook for eventual tail calls */
+ luaD_callhook(L, LUA_HOOKTAILRET, -1);
+ }
+ return restorestack(L, fr);
+}
+
+
+void luaD_poscall (lua_State *L, int wanted, StkId firstResult) {
+ StkId res;
+ if (L->hookmask & LUA_MASKRET)
+ firstResult = callrethooks(L, firstResult);
+ res = L->base - 1; /* res == final position of 1st result */
+ L->ci--;
+ L->base = L->ci->base; /* restore base */
+ /* move results to correct place */
+ while (wanted != 0 && firstResult < L->top) {
+ setobjs2s(res++, firstResult++);
+ wanted--;
+ }
+ while (wanted-- > 0)
+ setnilvalue(res++);
+ L->top = res;
+}
+
+
+/*
+** Call a function (C or Lua). The function to be called is at *func.
+** 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) {
+ StkId firstResult;
+ lua_assert(!(L->ci->state & CI_CALLING));
+ if (++L->nCcalls >= LUA_MAXCCALLS) {
+ if (L->nCcalls == LUA_MAXCCALLS)
+ luaG_runerror(L, "C stack overflow");
+ else if (L->nCcalls >= (LUA_MAXCCALLS + (LUA_MAXCCALLS>>3)))
+ luaD_throw(L, LUA_ERRERR); /* error while handing stack error */
+ }
+ firstResult = luaD_precall(L, func);
+ if (firstResult == NULL) /* is a Lua function? */
+ firstResult = luaV_execute(L); /* call it */
+ luaD_poscall(L, nResults, firstResult);
+ L->nCcalls--;
+ luaC_checkGC(L);
+}
+
+
+static void resume (lua_State *L, void *ud) {
+ StkId firstResult;
+ int nargs = *cast(int *, ud);
+ CallInfo *ci = L->ci;
+ if (ci == L->base_ci) { /* no activation record? */
+ if (nargs >= L->top - L->base)
+ luaG_runerror(L, "cannot resume dead coroutine");
+ luaD_precall(L, L->top - (nargs + 1)); /* start coroutine */
+ }
+ else if (ci->state & CI_YIELD) { /* inside a yield? */
+ if (ci->state & CI_C) { /* `common' yield? */
+ /* finish interrupted execution of `OP_CALL' */
+ int nresults;
+ lua_assert((ci-1)->state & CI_SAVEDPC);
+ lua_assert(GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_CALL ||
+ GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_TAILCALL);
+ nresults = GETARG_C(*((ci-1)->u.l.savedpc - 1)) - 1;
+ luaD_poscall(L, nresults, L->top - nargs); /* complete it */
+ if (nresults >= 0) L->top = L->ci->top;
+ }
+ else { /* yielded inside a hook: just continue its execution */
+ ci->state &= ~CI_YIELD;
+ }
+ }
+ else
+ luaG_runerror(L, "cannot resume non-suspended coroutine");
+ firstResult = luaV_execute(L);
+ if (firstResult != NULL) /* return? */
+ luaD_poscall(L, LUA_MULTRET, firstResult); /* finalize this coroutine */
+}
+
+
+LUA_API int lua_resume (lua_State *L, int nargs) {
+ int status;
+ lu_byte old_allowhooks;
+ lua_lock(L);
+ old_allowhooks = L->allowhook;
+ lua_assert(L->errfunc == 0 && L->nCcalls == 0);
+ status = luaD_rawrunprotected(L, resume, &nargs);
+ if (status != 0) { /* error? */
+ L->ci = L->base_ci; /* go back to initial level */
+ L->base = L->ci->base;
+ L->nCcalls = 0;
+ luaF_close(L, L->base); /* close eventual pending closures */
+ seterrorobj(L, status, L->base);
+ L->allowhook = old_allowhooks;
+ restore_stack_limit(L);
+ }
+ lua_unlock(L);
+ return status;
+}
+
+
+LUA_API int lua_yield (lua_State *L, int nresults) {
+ CallInfo *ci;
+ lua_lock(L);
+ ci = L->ci;
+ if (L->nCcalls > 0)
+ luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
+ if (ci->state & CI_C) { /* usual yield */
+ if ((ci-1)->state & CI_C)
+ luaG_runerror(L, "cannot yield a C function");
+ if (L->top - nresults > L->base) { /* is there garbage in the stack? */
+ int i;
+ for (i=0; i<nresults; i++) /* move down results */
+ setobjs2s(L->base + i, L->top - nresults + i);
+ L->top = L->base + nresults;
+ }
+ } /* else it's an yield inside a hook: nothing to do */
+ ci->state |= CI_YIELD;
+ lua_unlock(L);
+ return -1;
+}
+
+LUA_API void lua_break (lua_State *L) {
+ CallInfo * ci;
+ lua_lock(L);
+ ci = L->ci;
+ ci->state |= CI_BREAK;
+ lua_unlock(L);
+}
+
+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);
+ lu_byte old_allowhooks = L->allowhook;
+ ptrdiff_t old_errfunc = L->errfunc;
+ L->errfunc = ef;
+ status = luaD_rawrunprotected(L, func, u);
+ if (status != 0) { /* an error occurred? */
+ StkId oldtop = restorestack(L, old_top);
+ luaF_close(L, oldtop); /* close eventual pending closures */
+ seterrorobj(L, status, oldtop);
+ L->nCcalls = oldnCcalls;
+ L->ci = restoreci(L, old_ci);
+ L->base = L->ci->base;
+ L->allowhook = old_allowhooks;
+ restore_stack_limit(L);
+ }
+ L->errfunc = old_errfunc;
+ return status;
+}
+
+
+
+/*
+** Execute a protected parser.
+*/
+struct SParser { /* data to `f_parser' */
+ ZIO *z;
+ Mbuffer buff; /* buffer to be used by the scanner */
+ int bin;
+};
+
+static void f_parser (lua_State *L, void *ud) {
+ struct SParser *p;
+ Proto *tf;
+ Closure *cl;
+ luaC_checkGC(L);
+ p = cast(struct SParser *, ud);
+ tf = p->bin ? luaU_undump(L, p->z, &p->buff) : luaY_parser(L, p->z, &p->buff);
+ cl = luaF_newLclosure(L, 0, gt(L));
+ cl->l.p = tf;
+ setclvalue(L->top, cl);
+ incr_top(L);
+}
+
+
+int luaD_protectedparser (lua_State *L, ZIO *z, int bin) {
+ struct SParser p;
+ int status;
+ ptrdiff_t oldtopr = savestack(L, L->top); /* save current top */
+ p.z = z; p.bin = bin;
+ luaZ_initbuffer(L, &p.buff);
+ status = luaD_rawrunprotected(L, f_parser, &p);
+ luaZ_freebuffer(L, &p.buff);
+ if (status != 0) { /* error? */
+ StkId oldtop = restorestack(L, oldtopr);
+ seterrorobj(L, status, oldtop);
+ }
+ return status;
+}
+
+