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	Add loongarch64 definitions & lua module setjmp asm LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V. Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Han Gao <gaohan@uniontech.com> Signed-off-by: WANG Xuerui <xen0n@gentoo.org> Closes #13422
		
			
				
	
	
		
			763 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			763 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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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 <sys/asm_linkage.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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/* Return the number of bytes available on the stack. */
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#if defined (_KERNEL) && defined(__linux__)
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#include <asm/current.h>
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static intptr_t stack_remaining(void) {
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  intptr_t local;
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  local = (intptr_t)&local - (intptr_t)current->stack;
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  return local;
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}
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#elif defined (_KERNEL) && defined(__FreeBSD__)
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#include <sys/pcpu.h>
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static intptr_t stack_remaining(void) {
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  intptr_t local;
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  local = (intptr_t)&local - (intptr_t)curthread->td_kstack;
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  return local;
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}
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#else
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static intptr_t stack_remaining(void) {
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  return INTPTR_MAX;
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}
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#endif
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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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#ifdef __linux__
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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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#elif defined(__riscv)
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#define JMP_BUF_CNT     64
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#elif defined(__loongarch_lp64)
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#define JMP_BUF_CNT     64
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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 ASMABI setjmp(label_t *) __attribute__ ((__nothrow__));
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extern __attribute__((noreturn)) void ASMABI longjmp(label_t *);
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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 arches 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
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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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#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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/*
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 * Silence infinite recursion warning which was added to -Wall in gcc 12.1
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 */
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#if defined(__GNUC__) && !defined(__clang__) && \
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	defined(HAVE_KERNEL_INFINITE_RECURSION)
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#pragma GCC diagnostic push
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#pragma GCC diagnostic ignored "-Winfinite-recursion"
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#endif
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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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#if defined(__GNUC__) && !defined(__clang__) && \
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	defined(HAVE_INFINITE_RECURSION)
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#pragma GCC diagnostic pop
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#endif
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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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						|
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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);
 | 
						|
  StkId p;
 | 
						|
  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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						|
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						|
#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
 | 
						|
 | 
						|
 | 
						|
/*
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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;
 | 
						|
  int n;  /* number of arguments (Lua) or returns (C) */
 | 
						|
  ptrdiff_t funcr = savestack(L, func);
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						|
  switch (ttype(func)) {
 | 
						|
    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;
 | 
						|
      luaC_checkGC(L);  /* stack grow uses memory */
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						|
      if (L->hookmask & LUA_MASKCALL)
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						|
        luaD_hook(L, LUA_HOOKCALL, -1);
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						|
      lua_unlock(L);
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						|
      n = (*f)(L);  /* do the actual call */
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						|
      lua_lock(L);
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						|
      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 + p->numparams);
 | 
						|
      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->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 handling stack error */
 | 
						|
  }
 | 
						|
  intptr_t remaining = stack_remaining();
 | 
						|
  if (L->runerror == 0 && remaining < LUAI_MINCSTACK)
 | 
						|
    luaG_runerror(L, "C stack overflow");
 | 
						|
  if (L->runerror != 0 && remaining < LUAI_MINCSTACK / 2)
 | 
						|
    luaD_throw(L, LUA_ERRERR);  /* error while handling 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;
 | 
						|
}
 |