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-rw-r--r--deps/lua/src/ldo.c519
1 files changed, 519 insertions, 0 deletions
diff --git a/deps/lua/src/ldo.c b/deps/lua/src/ldo.c
new file mode 100644
index 0000000..e641dfc
--- /dev/null
+++ b/deps/lua/src/ldo.c
@@ -0,0 +1,519 @@
+/*
+** $Id: ldo.c,v 2.38.1.4 2012/01/18 02:27:10 roberto 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
+#define LUA_CORE
+
+#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
+** =======================================================
+*/
+
+
+/* chain list of long jump buffers */
+struct lua_longjmp {
+ struct lua_longjmp *previous;
+ luai_jmpbuf b;
+ volatile int status; /* error code */
+};
+
+
+void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+ switch (errcode) {
+ case LUA_ERRMEM: {
+ setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG));
+ break;
+ }
+ case LUA_ERRERR: {
+ setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
+ break;
+ }
+ case LUA_ERRSYNTAX:
+ case LUA_ERRRUN: {
+ setobjs2s(L, oldtop, L->top - 1); /* error message on current top */
+ break;
+ }
+ }
+ L->top = oldtop + 1;
+}
+
+
+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);
+ }
+}
+
+
+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);
+ }
+ 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;
+ LUAI_TRY(L, &lj,
+ (*f)(L, ud);
+ );
+ L->errorJmp = lj.previous; /* restore old error handler */
+ return lj.status;
+}
+
+/* }====================================================== */
+
+
+static void correctstack (lua_State *L, TValue *oldstack) {
+ CallInfo *ci;
+ GCObject *up;
+ 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++) {
+ ci->top = (ci->top - oldstack) + L->stack;
+ ci->base = (ci->base - oldstack) + L->stack;
+ ci->func = (ci->func - oldstack) + L->stack;
+ }
+ L->base = (L->base - oldstack) + L->stack;
+}
+
+
+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;
+ 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) {
+ if (n <= L->stacksize) /* double size is enough? */
+ luaD_reallocstack(L, 2*L->stacksize);
+ else
+ luaD_reallocstack(L, L->stacksize + n);
+}
+
+
+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_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 = cast_int(L->ci - L->base_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);
+ 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 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);
+ luaD_checkstack(L, p->maxstacksize);
+ 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
+ /* move fixed parameters to final position */
+ 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)));
+ }
+ return base;
+}
+
+
+static StkId tryfuncTM (lua_State *L, StkId func) {
+ const TValue *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(L, p, p-1);
+ incr_top(L);
+ func = restorestack(L, funcr); /* previous call may change stack */
+ setobj2s(L, func, tm); /* tag method is the new function to be called */
+ return func;
+}
+
+
+
+#define inc_ci(L) \
+ ((L->ci == L->end_ci) ? growCI(L) : \
+ (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci))
+
+
+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 + p->numparams);
+ 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 */
+ }
+ 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' */
+ }
+ 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;
+ }
+ }
+}
+
+
+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--;
+ 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 */
+ /* move results to correct place */
+ for (i = wanted; i != 0 && firstResult < L->top; i--)
+ setobjs2s(L, res++, firstResult++);
+ while (i-- > 0)
+ setnilvalue(res++);
+ L->top = res;
+ return (wanted - LUA_MULTRET); /* 0 iff wanted == LUA_MULTRET */
+}
+
+
+/*
+** 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) {
+ 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 */
+ L->nCcalls--;
+ luaC_checkGC(L);
+}
+
+
+static void resume (lua_State *L, void *ud) {
+ StkId firstArg = cast(StkId, ud);
+ 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;
+ }
+ 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 */
+ }
+ 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;
+}
+
+
+LUA_API int lua_resume (lua_State *L, int nargs) {
+ int status;
+ 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;
+ 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;
+ }
+ --L->nCcalls;
+ lua_unlock(L);
+ return status;
+}
+
+
+LUA_API int lua_yield (lua_State *L, int nresults) {
+ 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 */
+ L->status = LUA_YIELD;
+ lua_unlock(L);
+ return -1;
+}
+
+
+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 */
+ luaD_seterrorobj(L, status, oldtop);
+ L->nCcalls = oldnCcalls;
+ L->ci = restoreci(L, old_ci);
+ L->base = L->ci->base;
+ L->savedpc = L->ci->savedpc;
+ 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 */
+ const char *name;
+};
+
+static void f_parser (lua_State *L, void *ud) {
+ int i;
+ Proto *tf;
+ Closure *cl;
+ struct SParser *p = cast(struct SParser *, ud);
+ luaZ_lookahead(p->z);
+ luaC_checkGC(L);
+ tf = (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 luaD_protectedparser (lua_State *L, ZIO *z, const char *name) {
+ struct SParser p;
+ int status;
+ p.z = z; p.name = name;
+ luaZ_initbuffer(L, &p.buff);
+ status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
+ luaZ_freebuffer(L, &p.buff);
+ return status;
+}
+
+