1 /*
2 ** $Id: lfunc.cpp,v 1.1 2006/02/02 13:36:04 cavac Exp $
3 ** Auxiliary functions to manipulate prototypes and closures
4 ** See Copyright Notice in lua.h
5 */
6
7
8 #include <stdlib.h>
9
10 #define lfunc_c
11
12 #include "lua.h"
13
14 #include "lfunc.h"
15 #include "lgc.h"
16 #include "lmem.h"
17 #include "lobject.h"
18 #include "lstate.h"
19
20
21 #define sizeCclosure(n) (cast(int, sizeof(CClosure)) + \
22 cast(int, sizeof(TObject)*((n)-1)))
23
24 #define sizeLclosure(n) (cast(int, sizeof(LClosure)) + \
25 cast(int, sizeof(TObject *)*((n)-1)))
26
27
28
luaF_newCclosure(lua_State * L,int nelems)29 Closure *luaF_newCclosure (lua_State *L, int nelems) {
30 Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
31 luaC_link(L, valtogco(c), LUA_TFUNCTION);
32 c->c.isC = 1;
33 c->c.nupvalues = cast(lu_byte, nelems);
34 return c;
35 }
36
37
luaF_newLclosure(lua_State * L,int nelems,TObject * e)38 Closure *luaF_newLclosure (lua_State *L, int nelems, TObject *e) {
39 Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
40 luaC_link(L, valtogco(c), LUA_TFUNCTION);
41 c->l.isC = 0;
42 c->l.g = *e;
43 c->l.nupvalues = cast(lu_byte, nelems);
44 return c;
45 }
46
47
luaF_findupval(lua_State * L,StkId level)48 UpVal *luaF_findupval (lua_State *L, StkId level) {
49 GCObject **pp = &L->openupval;
50 UpVal *p;
51 UpVal *v;
52 while ((p = ngcotouv(*pp)) != NULL && p->v >= level) {
53 if (p->v == level) return p;
54 pp = &p->next;
55 }
56 v = luaM_new(L, UpVal); /* not found: create a new one */
57 v->tt = LUA_TUPVAL;
58 v->marked = 1; /* open upvalues should not be collected */
59 v->v = level; /* current value lives in the stack */
60 v->next = *pp; /* chain it in the proper position */
61 *pp = valtogco(v);
62 return v;
63 }
64
65
luaF_close(lua_State * L,StkId level)66 void luaF_close (lua_State *L, StkId level) {
67 UpVal *p;
68 while ((p = ngcotouv(L->openupval)) != NULL && p->v >= level) {
69 setobj(&p->value, p->v); /* save current value (write barrier) */
70 p->v = &p->value; /* now current value lives here */
71 L->openupval = p->next; /* remove from `open' list */
72 luaC_link(L, valtogco(p), LUA_TUPVAL);
73 }
74 }
75
76
luaF_newproto(lua_State * L)77 Proto *luaF_newproto (lua_State *L) {
78 Proto *f = luaM_new(L, Proto);
79 luaC_link(L, valtogco(f), LUA_TPROTO);
80 f->k = NULL;
81 f->sizek = 0;
82 f->p = NULL;
83 f->sizep = 0;
84 f->code = NULL;
85 f->sizecode = 0;
86 f->sizelineinfo = 0;
87 f->sizeupvalues = 0;
88 f->nups = 0;
89 f->upvalues = NULL;
90 f->numparams = 0;
91 f->is_vararg = 0;
92 f->maxstacksize = 0;
93 f->lineinfo = NULL;
94 f->sizelocvars = 0;
95 f->locvars = NULL;
96 f->lineDefined = 0;
97 f->source = NULL;
98 return f;
99 }
100
101
luaF_freeproto(lua_State * L,Proto * f)102 void luaF_freeproto (lua_State *L, Proto *f) {
103 luaM_freearray(L, f->code, f->sizecode, Instruction);
104 luaM_freearray(L, f->p, f->sizep, Proto *);
105 luaM_freearray(L, f->k, f->sizek, TObject);
106 luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
107 luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
108 luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
109 luaM_freelem(L, f);
110 }
111
112
luaF_freeclosure(lua_State * L,Closure * c)113 void luaF_freeclosure (lua_State *L, Closure *c) {
114 int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
115 sizeLclosure(c->l.nupvalues);
116 luaM_free(L, c, size);
117 }
118
119
120 /*
121 ** Look for n-th local variable at line `line' in function `func'.
122 ** Returns NULL if not found.
123 */
luaF_getlocalname(const Proto * f,int local_number,int pc)124 const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
125 int i;
126 for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
127 if (pc < f->locvars[i].endpc) { /* is variable active? */
128 local_number--;
129 if (local_number == 0)
130 return getstr(f->locvars[i].varname);
131 }
132 }
133 return NULL; /* not found */
134 }
135
136