717 lines
21 KiB
C
717 lines
21 KiB
C
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/* BEGIN CSTYLED */
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/*
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** $Id: ldo.c,v 2.108.1.3 2013/11/08 18:22:50 roberto Exp $
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** Stack and Call structure of Lua
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** See Copyright Notice in lua.h
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*/
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#define ldo_c
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#define LUA_CORE
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#include <sys/lua/lua.h>
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#include "lapi.h"
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#include "ldebug.h"
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#include "ldo.h"
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#include "lfunc.h"
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#include "lgc.h"
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#include "lmem.h"
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#include "lobject.h"
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#include "lopcodes.h"
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#include "lparser.h"
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#include "lstate.h"
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#include "lstring.h"
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#include "ltable.h"
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#include "ltm.h"
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#include "lvm.h"
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#include "lzio.h"
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/*
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** {======================================================
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** Error-recovery functions
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** =======================================================
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*/
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/*
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** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By
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** default, Lua handles errors with exceptions when compiling as
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** C++ code, with _longjmp/_setjmp when asked to use them, and with
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** longjmp/setjmp otherwise.
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*/
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#if !defined(LUAI_THROW)
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#ifdef _KERNEL
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#if defined(__i386__)
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#define JMP_BUF_CNT 6
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#elif defined(__x86_64__)
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#define JMP_BUF_CNT 8
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#elif defined(__sparc__) && defined(__arch64__)
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#define JMP_BUF_CNT 6
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#elif defined(__powerpc__)
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#define JMP_BUF_CNT 26
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#elif defined(__aarch64__)
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#define JMP_BUF_CNT 64
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#elif defined(__arm__)
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#define JMP_BUF_CNT 65
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#elif defined(__mips__)
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#define JMP_BUF_CNT 12
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#elif defined(__s390x__)
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#define JMP_BUF_CNT 18
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#else
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#define JMP_BUF_CNT 1
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#endif
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typedef struct _label_t { long long unsigned val[JMP_BUF_CNT]; } label_t;
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int setjmp(label_t *) __attribute__ ((__nothrow__));
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extern void longjmp(label_t *) __attribute__((__noreturn__));
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#define LUAI_THROW(L,c) longjmp(&(c)->b)
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#define LUAI_TRY(L,c,a) if (setjmp(&(c)->b) == 0) { a }
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#define luai_jmpbuf label_t
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/* unsupported archs will build but not be able to run lua programs */
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#if JMP_BUF_CNT == 1
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int setjmp (label_t *buf) {
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return 1;
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}
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void longjmp (label_t * buf) {
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for (;;);
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}
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#endif
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#else /* _KERNEL */
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#if defined(__cplusplus) && !defined(LUA_USE_LONGJMP)
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/* C++ exceptions */
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#define LUAI_THROW(L,c) throw(c)
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#define LUAI_TRY(L,c,a) \
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try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; }
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#define luai_jmpbuf int /* dummy variable */
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#elif defined(LUA_USE_ULONGJMP)
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/* in Unix, try _longjmp/_setjmp (more efficient) */
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#define LUAI_THROW(L,c) _longjmp((c)->b, 1)
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#define LUAI_TRY(L,c,a) if (_setjmp((c)->b) == 0) { a }
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#define luai_jmpbuf jmp_buf
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#else
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/* default handling with long jumps */
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#define LUAI_THROW(L,c) longjmp((c)->b, 1)
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#define LUAI_TRY(L,c,a) if (setjmp((c)->b) == 0) { a }
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#define luai_jmpbuf jmp_buf
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#endif
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#endif /* _KERNEL */
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#endif /* LUAI_THROW */
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/* chain list of long jump buffers */
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struct lua_longjmp {
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struct lua_longjmp *previous;
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luai_jmpbuf b;
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volatile int status; /* error code */
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};
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static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
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switch (errcode) {
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case LUA_ERRMEM: { /* memory error? */
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setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */
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break;
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}
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case LUA_ERRERR: {
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setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
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break;
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}
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default: {
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setobjs2s(L, oldtop, L->top - 1); /* error message on current top */
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break;
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}
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}
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L->top = oldtop + 1;
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}
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l_noret luaD_throw (lua_State *L, int errcode) {
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if (L->errorJmp) { /* thread has an error handler? */
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L->errorJmp->status = errcode; /* set status */
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LUAI_THROW(L, L->errorJmp); /* jump to it */
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}
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else { /* thread has no error handler */
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L->status = cast_byte(errcode); /* mark it as dead */
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if (G(L)->mainthread->errorJmp) { /* main thread has a handler? */
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setobjs2s(L, G(L)->mainthread->top++, L->top - 1); /* copy error obj. */
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luaD_throw(G(L)->mainthread, errcode); /* re-throw in main thread */
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}
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else { /* no handler at all; abort */
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if (G(L)->panic) { /* panic function? */
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lua_unlock(L);
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G(L)->panic(L); /* call it (last chance to jump out) */
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}
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panic("no error handler");
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}
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}
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}
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int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
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unsigned short oldnCcalls = L->nCcalls;
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struct lua_longjmp lj;
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lj.status = LUA_OK;
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lj.previous = L->errorJmp; /* chain new error handler */
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L->errorJmp = &lj;
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LUAI_TRY(L, &lj,
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(*f)(L, ud);
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);
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L->errorJmp = lj.previous; /* restore old error handler */
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L->nCcalls = oldnCcalls;
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return lj.status;
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}
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/* }====================================================== */
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static void correctstack (lua_State *L, TValue *oldstack) {
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CallInfo *ci;
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GCObject *up;
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L->top = (L->top - oldstack) + L->stack;
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for (up = L->openupval; up != NULL; up = up->gch.next)
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gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack;
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for (ci = L->ci; ci != NULL; ci = ci->previous) {
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ci->top = (ci->top - oldstack) + L->stack;
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ci->func = (ci->func - oldstack) + L->stack;
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if (isLua(ci))
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ci->u.l.base = (ci->u.l.base - oldstack) + L->stack;
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}
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}
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/* some space for error handling */
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#define ERRORSTACKSIZE (LUAI_MAXSTACK + 200)
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void luaD_reallocstack (lua_State *L, int newsize) {
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TValue *oldstack = L->stack;
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int lim = L->stacksize;
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lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE);
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lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK);
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luaM_reallocvector(L, L->stack, L->stacksize, newsize, TValue);
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for (; lim < newsize; lim++)
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setnilvalue(L->stack + lim); /* erase new segment */
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L->stacksize = newsize;
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L->stack_last = L->stack + newsize - EXTRA_STACK;
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correctstack(L, oldstack);
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}
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void luaD_growstack (lua_State *L, int n) {
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int size = L->stacksize;
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if (size > LUAI_MAXSTACK) /* error after extra size? */
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luaD_throw(L, LUA_ERRERR);
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else {
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int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK;
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int newsize = 2 * size;
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if (newsize > LUAI_MAXSTACK) newsize = LUAI_MAXSTACK;
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if (newsize < needed) newsize = needed;
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if (newsize > LUAI_MAXSTACK) { /* stack overflow? */
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luaD_reallocstack(L, ERRORSTACKSIZE);
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luaG_runerror(L, "stack overflow");
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}
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else
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luaD_reallocstack(L, newsize);
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}
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}
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static int stackinuse (lua_State *L) {
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CallInfo *ci;
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StkId lim = L->top;
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for (ci = L->ci; ci != NULL; ci = ci->previous) {
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lua_assert(ci->top <= L->stack_last);
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if (lim < ci->top) lim = ci->top;
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}
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return cast_int(lim - L->stack) + 1; /* part of stack in use */
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}
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void luaD_shrinkstack (lua_State *L) {
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int inuse = stackinuse(L);
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int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
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if (goodsize > LUAI_MAXSTACK) goodsize = LUAI_MAXSTACK;
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if (inuse > LUAI_MAXSTACK || /* handling stack overflow? */
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goodsize >= L->stacksize) /* would grow instead of shrink? */
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condmovestack(L); /* don't change stack (change only for debugging) */
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else
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luaD_reallocstack(L, goodsize); /* shrink it */
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}
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void luaD_hook (lua_State *L, int event, int line) {
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lua_Hook hook = L->hook;
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if (hook && L->allowhook) {
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CallInfo *ci = L->ci;
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ptrdiff_t top = savestack(L, L->top);
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ptrdiff_t ci_top = savestack(L, ci->top);
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lua_Debug ar;
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ar.event = event;
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ar.currentline = line;
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ar.i_ci = ci;
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luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
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ci->top = L->top + LUA_MINSTACK;
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lua_assert(ci->top <= L->stack_last);
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L->allowhook = 0; /* cannot call hooks inside a hook */
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ci->callstatus |= CIST_HOOKED;
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lua_unlock(L);
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(*hook)(L, &ar);
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lua_lock(L);
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lua_assert(!L->allowhook);
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L->allowhook = 1;
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ci->top = restorestack(L, ci_top);
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L->top = restorestack(L, top);
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ci->callstatus &= ~CIST_HOOKED;
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}
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}
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static void callhook (lua_State *L, CallInfo *ci) {
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int hook = LUA_HOOKCALL;
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ci->u.l.savedpc++; /* hooks assume 'pc' is already incremented */
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if (isLua(ci->previous) &&
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GET_OPCODE(*(ci->previous->u.l.savedpc - 1)) == OP_TAILCALL) {
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ci->callstatus |= CIST_TAIL;
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hook = LUA_HOOKTAILCALL;
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}
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luaD_hook(L, hook, -1);
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ci->u.l.savedpc--; /* correct 'pc' */
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}
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static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
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int i;
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int nfixargs = p->numparams;
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StkId base, fixed;
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lua_assert(actual >= nfixargs);
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/* move fixed parameters to final position */
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luaD_checkstack(L, p->maxstacksize); /* check again for new 'base' */
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fixed = L->top - actual; /* first fixed argument */
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base = L->top; /* final position of first argument */
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for (i=0; i<nfixargs; i++) {
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setobjs2s(L, L->top++, fixed + i);
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setnilvalue(fixed + i);
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}
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return base;
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}
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static StkId tryfuncTM (lua_State *L, StkId func) {
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const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL);
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StkId p;
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ptrdiff_t funcr = savestack(L, func);
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if (!ttisfunction(tm))
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luaG_typeerror(L, func, "call");
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/* Open a hole inside the stack at `func' */
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for (p = L->top; p > func; p--) setobjs2s(L, p, p-1);
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incr_top(L);
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func = restorestack(L, funcr); /* previous call may change stack */
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setobj2s(L, func, tm); /* tag method is the new function to be called */
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return func;
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}
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#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
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/*
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** returns true if function has been executed (C function)
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*/
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int luaD_precall (lua_State *L, StkId func, int nresults) {
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lua_CFunction f;
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CallInfo *ci;
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int n; /* number of arguments (Lua) or returns (C) */
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ptrdiff_t funcr = savestack(L, func);
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switch (ttype(func)) {
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case LUA_TLCF: /* light C function */
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f = fvalue(func);
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goto Cfunc;
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case LUA_TCCL: { /* C closure */
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f = clCvalue(func)->f;
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Cfunc:
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luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
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ci = next_ci(L); /* now 'enter' new function */
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ci->nresults = nresults;
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ci->func = restorestack(L, funcr);
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ci->top = L->top + LUA_MINSTACK;
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lua_assert(ci->top <= L->stack_last);
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ci->callstatus = 0;
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luaC_checkGC(L); /* stack grow uses memory */
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|
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;
|
||
|
|
}
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
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 */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int luaD_poscall (lua_State *L, StkId firstResult) {
|
||
|
|
StkId res;
|
||
|
|
int wanted, i;
|
||
|
|
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->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++);
|
||
|
|
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, 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 (!allowyield) L->nny++;
|
||
|
|
if (!luaD_precall(L, func, nResults)) /* is a Lua function? */
|
||
|
|
luaV_execute(L); /* call it */
|
||
|
|
if (!allowyield) L->nny--;
|
||
|
|
L->nCcalls--;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static void finishCcall (lua_State *L) {
|
||
|
|
CallInfo *ci = L->ci;
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
/* 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' */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
** 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' */
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
** do the work for 'lua_resume' in protected mode
|
||
|
|
*/
|
||
|
|
static void resume_cb (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);
|
||
|
|
luai_userstateresume(L, nargs);
|
||
|
|
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_cb, L->top - nargs);
|
||
|
|
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->nny = oldnny; /* restore 'nny' */
|
||
|
|
L->nCcalls--;
|
||
|
|
lua_assert(L->nCcalls == ((from) ? from->nCcalls : 0));
|
||
|
|
lua_unlock(L);
|
||
|
|
return status;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
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);
|
||
|
|
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 0; /* return to 'luaD_hook' */
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int luaD_pcall (lua_State *L, Pfunc func, void *u,
|
||
|
|
ptrdiff_t old_top, ptrdiff_t ef) {
|
||
|
|
int status;
|
||
|
|
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 != LUA_OK) { /* an error occurred? */
|
||
|
|
StkId oldtop = restorestack(L, old_top);
|
||
|
|
luaF_close(L, oldtop); /* close possible pending closures */
|
||
|
|
seterrorobj(L, status, oldtop);
|
||
|
|
L->ci = old_ci;
|
||
|
|
L->allowhook = old_allowhooks;
|
||
|
|
L->nny = old_nny;
|
||
|
|
luaD_shrinkstack(L);
|
||
|
|
}
|
||
|
|
L->errfunc = old_errfunc;
|
||
|
|
return status;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Execute a protected parser.
|
||
|
|
*/
|
||
|
|
struct SParser { /* data to `f_parser' */
|
||
|
|
ZIO *z;
|
||
|
|
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;
|
||
|
|
Closure *cl;
|
||
|
|
struct SParser *p = cast(struct SParser *, ud);
|
||
|
|
int c = zgetc(p->z); /* read first character */
|
||
|
|
lua_assert(c != LUA_SIGNATURE[0]); /* binary not supported */
|
||
|
|
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,
|
||
|
|
const char *mode) {
|
||
|
|
struct SParser p;
|
||
|
|
int status;
|
||
|
|
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;
|
||
|
|
}
|
||
|
|
/* END CSTYLED */
|