1 /* $NetBSD: lfunc.c,v 1.3 2015/02/02 14:03:05 lneto Exp $ */
2
3 /*
4 ** Id: lfunc.c,v 2.45 2014/11/02 19:19:04 roberto Exp
5 ** Auxiliary functions to manipulate prototypes and closures
6 ** See Copyright Notice in lua.h
7 */
8
9 #define lfunc_c
10 #define LUA_CORE
11
12 #include "lprefix.h"
13
14
15 #ifndef _KERNEL
16 #include <stddef.h>
17 #endif
18
19 #include "lua.h"
20
21 #include "lfunc.h"
22 #include "lgc.h"
23 #include "lmem.h"
24 #include "lobject.h"
25 #include "lstate.h"
26
27
28
luaF_newCclosure(lua_State * L,int n)29 CClosure *luaF_newCclosure (lua_State *L, int n) {
30 GCObject *o = luaC_newobj(L, LUA_TCCL, sizeCclosure(n));
31 CClosure *c = gco2ccl(o);
32 c->nupvalues = cast_byte(n);
33 return c;
34 }
35
36
luaF_newLclosure(lua_State * L,int n)37 LClosure *luaF_newLclosure (lua_State *L, int n) {
38 GCObject *o = luaC_newobj(L, LUA_TLCL, sizeLclosure(n));
39 LClosure *c = gco2lcl(o);
40 c->p = NULL;
41 c->nupvalues = cast_byte(n);
42 while (n--) c->upvals[n] = NULL;
43 return c;
44 }
45
46 /*
47 ** fill a closure with new closed upvalues
48 */
luaF_initupvals(lua_State * L,LClosure * cl)49 void luaF_initupvals (lua_State *L, LClosure *cl) {
50 int i;
51 for (i = 0; i < cl->nupvalues; i++) {
52 UpVal *uv = luaM_new(L, UpVal);
53 uv->refcount = 1;
54 uv->v = &uv->u.value; /* make it closed */
55 setnilvalue(uv->v);
56 cl->upvals[i] = uv;
57 }
58 }
59
60
luaF_findupval(lua_State * L,StkId level)61 UpVal *luaF_findupval (lua_State *L, StkId level) {
62 UpVal **pp = &L->openupval;
63 UpVal *p;
64 UpVal *uv;
65 lua_assert(isintwups(L) || L->openupval == NULL);
66 while (*pp != NULL && (p = *pp)->v >= level) {
67 lua_assert(upisopen(p));
68 if (p->v == level) /* found a corresponding upvalue? */
69 return p; /* return it */
70 pp = &p->u.open.next;
71 }
72 /* not found: create a new upvalue */
73 uv = luaM_new(L, UpVal);
74 uv->refcount = 0;
75 uv->u.open.next = *pp; /* link it to list of open upvalues */
76 uv->u.open.touched = 1;
77 *pp = uv;
78 uv->v = level; /* current value lives in the stack */
79 if (!isintwups(L)) { /* thread not in list of threads with upvalues? */
80 L->twups = G(L)->twups; /* link it to the list */
81 G(L)->twups = L;
82 }
83 return uv;
84 }
85
86
luaF_close(lua_State * L,StkId level)87 void luaF_close (lua_State *L, StkId level) {
88 UpVal *uv;
89 while (L->openupval != NULL && (uv = L->openupval)->v >= level) {
90 lua_assert(upisopen(uv));
91 L->openupval = uv->u.open.next; /* remove from 'open' list */
92 if (uv->refcount == 0) /* no references? */
93 luaM_free(L, uv); /* free upvalue */
94 else {
95 setobj(L, &uv->u.value, uv->v); /* move value to upvalue slot */
96 uv->v = &uv->u.value; /* now current value lives here */
97 luaC_upvalbarrier(L, uv);
98 }
99 }
100 }
101
102
luaF_newproto(lua_State * L)103 Proto *luaF_newproto (lua_State *L) {
104 GCObject *o = luaC_newobj(L, LUA_TPROTO, sizeof(Proto));
105 Proto *f = gco2p(o);
106 f->k = NULL;
107 f->sizek = 0;
108 f->p = NULL;
109 f->sizep = 0;
110 f->code = NULL;
111 f->cache = NULL;
112 f->sizecode = 0;
113 f->lineinfo = NULL;
114 f->sizelineinfo = 0;
115 f->upvalues = NULL;
116 f->sizeupvalues = 0;
117 f->numparams = 0;
118 f->is_vararg = 0;
119 f->maxstacksize = 0;
120 f->locvars = NULL;
121 f->sizelocvars = 0;
122 f->linedefined = 0;
123 f->lastlinedefined = 0;
124 f->source = NULL;
125 return f;
126 }
127
128
luaF_freeproto(lua_State * L,Proto * f)129 void luaF_freeproto (lua_State *L, Proto *f) {
130 luaM_freearray(L, f->code, f->sizecode);
131 luaM_freearray(L, f->p, f->sizep);
132 luaM_freearray(L, f->k, f->sizek);
133 luaM_freearray(L, f->lineinfo, f->sizelineinfo);
134 luaM_freearray(L, f->locvars, f->sizelocvars);
135 luaM_freearray(L, f->upvalues, f->sizeupvalues);
136 luaM_free(L, f);
137 }
138
139
140 /*
141 ** Look for n-th local variable at line 'line' in function 'func'.
142 ** Returns NULL if not found.
143 */
luaF_getlocalname(const Proto * f,int local_number,int pc)144 const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
145 int i;
146 for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
147 if (pc < f->locvars[i].endpc) { /* is variable active? */
148 local_number--;
149 if (local_number == 0)
150 return getstr(f->locvars[i].varname);
151 }
152 }
153 return NULL; /* not found */
154 }
155
156