lfunc.c 4.8 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185
  1. /*
  2. ** $Id: lfunc.c,v 2.12.1.2 2007/12/28 14:58:43 roberto Exp $
  3. ** Auxiliary functions to manipulate prototypes and closures
  4. ** See Copyright Notice in lua.h
  5. */
  6. #define lfunc_c
  7. #define LUA_CORE
  8. #define LUAC_CROSS_FILE
  9. #include "lua.h"
  10. #include C_HEADER_STRING
  11. #include "lfunc.h"
  12. #include "lgc.h"
  13. #include "lmem.h"
  14. #include "lobject.h"
  15. #include "lstate.h"
  16. Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
  17. Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
  18. luaC_link(L, obj2gco(c), LUA_TFUNCTION);
  19. c->c.isC = 1;
  20. c->c.env = e;
  21. c->c.nupvalues = cast_byte(nelems);
  22. return c;
  23. }
  24. Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e) {
  25. Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
  26. luaC_link(L, obj2gco(c), LUA_TFUNCTION);
  27. c->l.isC = 0;
  28. c->l.env = e;
  29. c->l.nupvalues = cast_byte(nelems);
  30. while (nelems--) c->l.upvals[nelems] = NULL;
  31. return c;
  32. }
  33. UpVal *luaF_newupval (lua_State *L) {
  34. UpVal *uv = luaM_new(L, UpVal);
  35. luaC_link(L, obj2gco(uv), LUA_TUPVAL);
  36. uv->v = &uv->u.value;
  37. setnilvalue(uv->v);
  38. return uv;
  39. }
  40. UpVal *luaF_findupval (lua_State *L, StkId level) {
  41. global_State *g = G(L);
  42. GCObject **pp = &L->openupval;
  43. UpVal *p;
  44. UpVal *uv;
  45. while (*pp != NULL && (p = ngcotouv(*pp))->v >= level) {
  46. lua_assert(p->v != &p->u.value);
  47. if (p->v == level) { /* found a corresponding upvalue? */
  48. if (isdead(g, obj2gco(p))) /* is it dead? */
  49. changewhite(obj2gco(p)); /* ressurect it */
  50. return p;
  51. }
  52. pp = &p->next;
  53. }
  54. uv = luaM_new(L, UpVal); /* not found: create a new one */
  55. uv->tt = LUA_TUPVAL;
  56. uv->v = level; /* current value lives in the stack */
  57. uv->next = *pp; /* chain it in the proper position */
  58. *pp = obj2gco(uv);
  59. uv->u.l.prev = &g->uvhead; /* double link it in `uvhead' list */
  60. uv->u.l.next = g->uvhead.u.l.next;
  61. uv->u.l.next->u.l.prev = uv;
  62. g->uvhead.u.l.next = uv;
  63. luaC_marknew(L, obj2gco(uv));
  64. lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
  65. return uv;
  66. }
  67. static void unlinkupval (UpVal *uv) {
  68. lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
  69. uv->u.l.next->u.l.prev = uv->u.l.prev; /* remove from `uvhead' list */
  70. uv->u.l.prev->u.l.next = uv->u.l.next;
  71. }
  72. void luaF_freeupval (lua_State *L, UpVal *uv) {
  73. if (uv->v != &uv->u.value) /* is it open? */
  74. unlinkupval(uv); /* remove from open list */
  75. luaM_free(L, uv); /* free upvalue */
  76. }
  77. void luaF_close (lua_State *L, StkId level) {
  78. UpVal *uv;
  79. global_State *g = G(L);
  80. while (L->openupval != NULL && (uv = ngcotouv(L->openupval))->v >= level) {
  81. GCObject *o = obj2gco(uv);
  82. lua_assert(!isblack(o) && uv->v != &uv->u.value);
  83. L->openupval = uv->next; /* remove from `open' list */
  84. if (isdead(g, o))
  85. luaF_freeupval(L, uv); /* free upvalue */
  86. else {
  87. unlinkupval(uv);
  88. setobj(L, &uv->u.value, uv->v);
  89. uv->v = &uv->u.value; /* now current value lives here */
  90. luaC_linkupval(L, uv); /* link upvalue into `gcroot' list */
  91. }
  92. }
  93. }
  94. Proto *luaF_newproto (lua_State *L) {
  95. Proto *f = luaM_new(L, Proto);
  96. luaC_link(L, obj2gco(f), LUA_TPROTO);
  97. f->k = NULL;
  98. f->sizek = 0;
  99. f->p = NULL;
  100. f->sizep = 0;
  101. f->code = NULL;
  102. f->sizecode = 0;
  103. f->sizeupvalues = 0;
  104. f->nups = 0;
  105. f->upvalues = NULL;
  106. f->numparams = 0;
  107. f->is_vararg = 0;
  108. f->maxstacksize = 0;
  109. #ifdef LUA_OPTIMIZE_DEBUG
  110. f->packedlineinfo = NULL;
  111. #else
  112. f->sizelineinfo = 0;
  113. f->lineinfo = NULL;
  114. #endif
  115. f->sizelocvars = 0;
  116. f->locvars = NULL;
  117. f->linedefined = 0;
  118. f->lastlinedefined = 0;
  119. f->source = NULL;
  120. return f;
  121. }
  122. void luaF_freeproto (lua_State *L, Proto *f) {
  123. luaM_freearray(L, f->p, f->sizep, Proto *);
  124. luaM_freearray(L, f->k, f->sizek, TValue);
  125. luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
  126. luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
  127. if (!proto_isreadonly(f)) {
  128. luaM_freearray(L, f->code, f->sizecode, Instruction);
  129. #ifdef LUA_OPTIMIZE_DEBUG
  130. if (f->packedlineinfo) {
  131. luaM_freearray(L, f->packedlineinfo, c_strlen(cast(char *, f->packedlineinfo))+1, unsigned char);
  132. }
  133. #else
  134. luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
  135. #endif
  136. }
  137. luaM_free(L, f);
  138. }
  139. void luaF_freeclosure (lua_State *L, Closure *c) {
  140. int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
  141. sizeLclosure(c->l.nupvalues);
  142. luaM_freemem(L, c, size);
  143. }
  144. /*
  145. ** Look for n-th local variable at line `line' in function `func'.
  146. ** Returns NULL if not found.
  147. */
  148. const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
  149. int i;
  150. for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
  151. if (pc < f->locvars[i].endpc) { /* is variable active? */
  152. local_number--;
  153. if (local_number == 0)
  154. return getstr(f->locvars[i].varname);
  155. }
  156. }
  157. return NULL; /* not found */
  158. }