xref: /freebsd/contrib/lua/src/ldo.h (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*
2 ** $Id: ldo.h $
3 ** Stack and Call structure of Lua
4 ** See Copyright Notice in lua.h
5 */
6 
7 #ifndef ldo_h
8 #define ldo_h
9 
10 
11 #include "llimits.h"
12 #include "lobject.h"
13 #include "lstate.h"
14 #include "lzio.h"
15 
16 
17 /*
18 ** Macro to check stack size and grow stack if needed.  Parameters
19 ** 'pre'/'pos' allow the macro to preserve a pointer into the
20 ** stack across reallocations, doing the work only when needed.
21 ** It also allows the running of one GC step when the stack is
22 ** reallocated.
23 ** 'condmovestack' is used in heavy tests to force a stack reallocation
24 ** at every check.
25 */
26 #define luaD_checkstackaux(L,n,pre,pos)  \
27 	if (l_unlikely(L->stack_last.p - L->top.p <= (n))) \
28 	  { pre; luaD_growstack(L, n, 1); pos; } \
29         else { condmovestack(L,pre,pos); }
30 
31 /* In general, 'pre'/'pos' are empty (nothing to save) */
32 #define luaD_checkstack(L,n)	luaD_checkstackaux(L,n,(void)0,(void)0)
33 
34 
35 
36 #define savestack(L,pt)		(cast_charp(pt) - cast_charp(L->stack.p))
37 #define restorestack(L,n)	cast(StkId, cast_charp(L->stack.p) + (n))
38 
39 
40 /* macro to check stack size, preserving 'p' */
41 #define checkstackp(L,n,p)  \
42   luaD_checkstackaux(L, n, \
43     ptrdiff_t t__ = savestack(L, p),  /* save 'p' */ \
44     p = restorestack(L, t__))  /* 'pos' part: restore 'p' */
45 
46 
47 /* macro to check stack size and GC, preserving 'p' */
48 #define checkstackGCp(L,n,p)  \
49   luaD_checkstackaux(L, n, \
50     ptrdiff_t t__ = savestack(L, p);  /* save 'p' */ \
51     luaC_checkGC(L),  /* stack grow uses memory */ \
52     p = restorestack(L, t__))  /* 'pos' part: restore 'p' */
53 
54 
55 /* macro to check stack size and GC */
56 #define checkstackGC(L,fsize)  \
57 	luaD_checkstackaux(L, (fsize), luaC_checkGC(L), (void)0)
58 
59 
60 /* type of protected functions, to be ran by 'runprotected' */
61 typedef void (*Pfunc) (lua_State *L, void *ud);
62 
63 LUAI_FUNC void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop);
64 LUAI_FUNC int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
65                                                   const char *mode);
66 LUAI_FUNC void luaD_hook (lua_State *L, int event, int line,
67                                         int fTransfer, int nTransfer);
68 LUAI_FUNC void luaD_hookcall (lua_State *L, CallInfo *ci);
69 LUAI_FUNC int luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func,
70                                               int narg1, int delta);
71 LUAI_FUNC CallInfo *luaD_precall (lua_State *L, StkId func, int nResults);
72 LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults);
73 LUAI_FUNC void luaD_callnoyield (lua_State *L, StkId func, int nResults);
74 LUAI_FUNC StkId luaD_tryfuncTM (lua_State *L, StkId func);
75 LUAI_FUNC int luaD_closeprotected (lua_State *L, ptrdiff_t level, int status);
76 LUAI_FUNC int luaD_pcall (lua_State *L, Pfunc func, void *u,
77                                         ptrdiff_t oldtop, ptrdiff_t ef);
78 LUAI_FUNC void luaD_poscall (lua_State *L, CallInfo *ci, int nres);
79 LUAI_FUNC int luaD_reallocstack (lua_State *L, int newsize, int raiseerror);
80 LUAI_FUNC int luaD_growstack (lua_State *L, int n, int raiseerror);
81 LUAI_FUNC void luaD_shrinkstack (lua_State *L);
82 LUAI_FUNC void luaD_inctop (lua_State *L);
83 
84 LUAI_FUNC l_noret luaD_throw (lua_State *L, int errcode);
85 LUAI_FUNC int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud);
86 
87 #endif
88 
89