diff options
Diffstat (limited to 'src/lapi.c')
| -rw-r--r-- | src/lapi.c | 1087 |
1 files changed, 1087 insertions, 0 deletions
diff --git a/src/lapi.c b/src/lapi.c new file mode 100644 index 0000000..5d5145d --- /dev/null +++ b/src/lapi.c @@ -0,0 +1,1087 @@ +/* +** $Id: lapi.c,v 2.55.1.5 2008/07/04 18:41:18 roberto Exp $ +** Lua API +** See Copyright Notice in lua.h +*/ + + +#include <assert.h> +#include <math.h> +#include <stdarg.h> +#include <string.h> + +#define lapi_c +#define LUA_CORE + +#include "lua.h" + +#include "lapi.h" +#include "ldebug.h" +#include "ldo.h" +#include "lfunc.h" +#include "lgc.h" +#include "lmem.h" +#include "lobject.h" +#include "lstate.h" +#include "lstring.h" +#include "ltable.h" +#include "ltm.h" +#include "lundump.h" +#include "lvm.h" + + + +const char lua_ident[] = + "$Lua: " LUA_RELEASE " " LUA_COPYRIGHT " $\n" + "$Authors: " LUA_AUTHORS " $\n" + "$URL: www.lua.org $\n"; + + + +#define api_checknelems(L, n) api_check(L, (n) <= (L->top - L->base)) + +#define api_checkvalidindex(L, i) api_check(L, (i) != luaO_nilobject) + +#define api_incr_top(L) {api_check(L, L->top < L->ci->top); L->top++;} + + + +static TValue *index2adr (lua_State *L, int idx) { + if (idx > 0) { + TValue *o = L->base + (idx - 1); + api_check(L, idx <= L->ci->top - L->base); + if (o >= L->top) return cast(TValue *, luaO_nilobject); + else return o; + } + else if (idx > LUA_REGISTRYINDEX) { + api_check(L, idx != 0 && -idx <= L->top - L->base); + return L->top + idx; + } + else switch (idx) { /* pseudo-indices */ + case LUA_REGISTRYINDEX: return registry(L); + case LUA_ENVIRONINDEX: { + Closure *func = curr_func(L); + sethvalue(L, &L->env, func->c.env); + return &L->env; + } + case LUA_GLOBALSINDEX: return gt(L); + default: { + Closure *func = curr_func(L); + idx = LUA_GLOBALSINDEX - idx; + return (idx <= func->c.nupvalues) + ? &func->c.upvalue[idx-1] + : cast(TValue *, luaO_nilobject); + } + } +} + + +static Table *getcurrenv (lua_State *L) { + if (L->ci == L->base_ci) /* no enclosing function? */ + return hvalue(gt(L)); /* use global table as environment */ + else { + Closure *func = curr_func(L); + return func->c.env; + } +} + + +void luaA_pushobject (lua_State *L, const TValue *o) { + setobj2s(L, L->top, o); + api_incr_top(L); +} + + +LUA_API int lua_checkstack (lua_State *L, int size) { + int res = 1; + lua_lock(L); + if (size > LUAI_MAXCSTACK || (L->top - L->base + size) > LUAI_MAXCSTACK) + res = 0; /* stack overflow */ + else if (size > 0) { + luaD_checkstack(L, size); + if (L->ci->top < L->top + size) + L->ci->top = L->top + size; + } + lua_unlock(L); + return res; +} + + +LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) { + int i; + if (from == to) return; + lua_lock(to); + api_checknelems(from, n); + api_check(from, G(from) == G(to)); + api_check(from, to->ci->top - to->top >= n); + from->top -= n; + for (i = 0; i < n; i++) { + setobj2s(to, to->top++, from->top + i); + } + lua_unlock(to); +} + + +LUA_API void lua_setlevel (lua_State *from, lua_State *to) { + to->nCcalls = from->nCcalls; +} + + +LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) { + lua_CFunction old; + lua_lock(L); + old = G(L)->panic; + G(L)->panic = panicf; + lua_unlock(L); + return old; +} + + +LUA_API lua_State *lua_newthread (lua_State *L) { + lua_State *L1; + lua_lock(L); + luaC_checkGC(L); + L1 = luaE_newthread(L); + setthvalue(L, L->top, L1); + api_incr_top(L); + lua_unlock(L); + luai_userstatethread(L, L1); + return L1; +} + + + +/* +** basic stack manipulation +*/ + + +LUA_API int lua_gettop (lua_State *L) { + return cast_int(L->top - L->base); +} + + +LUA_API void lua_settop (lua_State *L, int idx) { + lua_lock(L); + if (idx >= 0) { + api_check(L, idx <= L->stack_last - L->base); + while (L->top < L->base + idx) + setnilvalue(L->top++); + L->top = L->base + idx; + } + else { + api_check(L, -(idx+1) <= (L->top - L->base)); + L->top += idx+1; /* `subtract' index (index is negative) */ + } + lua_unlock(L); +} + + +LUA_API void lua_remove (lua_State *L, int idx) { + StkId p; + lua_lock(L); + p = index2adr(L, idx); + api_checkvalidindex(L, p); + while (++p < L->top) setobjs2s(L, p-1, p); + L->top--; + lua_unlock(L); +} + + +LUA_API void lua_insert (lua_State *L, int idx) { + StkId p; + StkId q; + lua_lock(L); + p = index2adr(L, idx); + api_checkvalidindex(L, p); + for (q = L->top; q>p; q--) setobjs2s(L, q, q-1); + setobjs2s(L, p, L->top); + lua_unlock(L); +} + + +LUA_API void lua_replace (lua_State *L, int idx) { + StkId o; + lua_lock(L); + /* explicit test for incompatible code */ + if (idx == LUA_ENVIRONINDEX && L->ci == L->base_ci) + luaG_runerror(L, "no calling environment"); + api_checknelems(L, 1); + o = index2adr(L, idx); + api_checkvalidindex(L, o); + if (idx == LUA_ENVIRONINDEX) { + Closure *func = curr_func(L); + api_check(L, ttistable(L->top - 1)); + func->c.env = hvalue(L->top - 1); + luaC_barrier(L, func, L->top - 1); + } + else { + setobj(L, o, L->top - 1); + if (idx < LUA_GLOBALSINDEX) /* function upvalue? */ + luaC_barrier(L, curr_func(L), L->top - 1); + } + L->top--; + lua_unlock(L); +} + + +LUA_API void lua_pushvalue (lua_State *L, int idx) { + lua_lock(L); + setobj2s(L, L->top, index2adr(L, idx)); + api_incr_top(L); + lua_unlock(L); +} + + + +/* +** access functions (stack -> C) +*/ + + +LUA_API int lua_type (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + return (o == luaO_nilobject) ? LUA_TNONE : ttype(o); +} + + +LUA_API const char *lua_typename (lua_State *L, int t) { + UNUSED(L); + return (t == LUA_TNONE) ? "no value" : luaT_typenames[t]; +} + + +LUA_API int lua_iscfunction (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + return iscfunction(o); +} + + +LUA_API int lua_isnumber (lua_State *L, int idx) { + TValue n; + const TValue *o = index2adr(L, idx); + return tonumber(o, &n); +} + + +LUA_API int lua_isstring (lua_State *L, int idx) { + int t = lua_type(L, idx); + return (t == LUA_TSTRING || t == LUA_TNUMBER); +} + + +LUA_API int lua_isuserdata (lua_State *L, int idx) { + const TValue *o = index2adr(L, idx); + return (ttisuserdata(o) || ttislightuserdata(o)); +} + + +LUA_API int lua_rawequal (lua_State *L, int index1, int index2) { + StkId o1 = index2adr(L, index1); + StkId o2 = index2adr(L, index2); + return (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 + : luaO_rawequalObj(o1, o2); +} + + +LUA_API int lua_equal (lua_State *L, int index1, int index2) { + StkId o1, o2; + int i; + lua_lock(L); /* may call tag method */ + o1 = index2adr(L, index1); + o2 = index2adr(L, index2); + i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 : equalobj(L, o1, o2); + lua_unlock(L); + return i; +} + + +LUA_API int lua_lessthan (lua_State *L, int index1, int index2) { + StkId o1, o2; + int i; + lua_lock(L); /* may call tag method */ + o1 = index2adr(L, index1); + o2 = index2adr(L, index2); + i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 + : luaV_lessthan(L, o1, o2); + lua_unlock(L); + return i; +} + + + +LUA_API lua_Number lua_tonumber (lua_State *L, int idx) { + TValue n; + const TValue *o = index2adr(L, idx); + if (tonumber(o, &n)) + return nvalue(o); + else + return 0; +} + + +LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) { + TValue n; + const TValue *o = index2adr(L, idx); + if (tonumber(o, &n)) { + lua_Integer res; + lua_Number num = nvalue(o); + lua_number2integer(res, num); + return res; + } + else + return 0; +} + + +LUA_API int lua_toboolean (lua_State *L, int idx) { + const TValue *o = index2adr(L, idx); + return !l_isfalse(o); +} + + +LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) { + StkId o = index2adr(L, idx); + if (!ttisstring(o)) { + lua_lock(L); /* `luaV_tostring' may create a new string */ + if (!luaV_tostring(L, o)) { /* conversion failed? */ + if (len != NULL) *len = 0; + lua_unlock(L); + return NULL; + } + luaC_checkGC(L); + o = index2adr(L, idx); /* previous call may reallocate the stack */ + lua_unlock(L); + } + if (len != NULL) *len = tsvalue(o)->len; + return svalue(o); +} + + +LUA_API size_t lua_objlen (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + switch (ttype(o)) { + case LUA_TSTRING: return tsvalue(o)->len; + case LUA_TUSERDATA: return uvalue(o)->len; + case LUA_TTABLE: return luaH_getn(hvalue(o)); + case LUA_TNUMBER: { + size_t l; + lua_lock(L); /* `luaV_tostring' may create a new string */ + l = (luaV_tostring(L, o) ? tsvalue(o)->len : 0); + lua_unlock(L); + return l; + } + default: return 0; + } +} + + +LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + return (!iscfunction(o)) ? NULL : clvalue(o)->c.f; +} + + +LUA_API void *lua_touserdata (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + switch (ttype(o)) { + case LUA_TUSERDATA: return (rawuvalue(o) + 1); + case LUA_TLIGHTUSERDATA: return pvalue(o); + default: return NULL; + } +} + + +LUA_API lua_State *lua_tothread (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + return (!ttisthread(o)) ? NULL : thvalue(o); +} + + +LUA_API const void *lua_topointer (lua_State *L, int idx) { + StkId o = index2adr(L, idx); + switch (ttype(o)) { + case LUA_TTABLE: return hvalue(o); + case LUA_TFUNCTION: return clvalue(o); + case LUA_TTHREAD: return thvalue(o); + case LUA_TUSERDATA: + case LUA_TLIGHTUSERDATA: + return lua_touserdata(L, idx); + default: return NULL; + } +} + + + +/* +** push functions (C -> stack) +*/ + + +LUA_API void lua_pushnil (lua_State *L) { + lua_lock(L); + setnilvalue(L->top); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushnumber (lua_State *L, lua_Number n) { + lua_lock(L); + setnvalue(L->top, n); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) { + lua_lock(L); + setnvalue(L->top, cast_num(n)); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) { + lua_lock(L); + luaC_checkGC(L); + setsvalue2s(L, L->top, luaS_newlstr(L, s, len)); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushstring (lua_State *L, const char *s) { + if (s == NULL) + lua_pushnil(L); + else + lua_pushlstring(L, s, strlen(s)); +} + + +LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt, + va_list argp) { + const char *ret; + lua_lock(L); + luaC_checkGC(L); + ret = luaO_pushvfstring(L, fmt, argp); + lua_unlock(L); + return ret; +} + + +LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) { + const char *ret; + va_list argp; + lua_lock(L); + luaC_checkGC(L); + va_start(argp, fmt); + ret = luaO_pushvfstring(L, fmt, argp); + va_end(argp); + lua_unlock(L); + return ret; +} + + +LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) { + Closure *cl; + lua_lock(L); + luaC_checkGC(L); + api_checknelems(L, n); + cl = luaF_newCclosure(L, n, getcurrenv(L)); + cl->c.f = fn; + L->top -= n; + while (n--) + setobj2n(L, &cl->c.upvalue[n], L->top+n); + setclvalue(L, L->top, cl); + lua_assert(iswhite(obj2gco(cl))); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushboolean (lua_State *L, int b) { + lua_lock(L); + setbvalue(L->top, (b != 0)); /* ensure that true is 1 */ + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_pushlightuserdata (lua_State *L, void *p) { + lua_lock(L); + setpvalue(L->top, p); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API int lua_pushthread (lua_State *L) { + lua_lock(L); + setthvalue(L, L->top, L); + api_incr_top(L); + lua_unlock(L); + return (G(L)->mainthread == L); +} + + + +/* +** get functions (Lua -> stack) +*/ + + +LUA_API void lua_gettable (lua_State *L, int idx) { + StkId t; + lua_lock(L); + t = index2adr(L, idx); + api_checkvalidindex(L, t); + luaV_gettable(L, t, L->top - 1, L->top - 1); + lua_unlock(L); +} + + +LUA_API void lua_getfield (lua_State *L, int idx, const char *k) { + StkId t; + TValue key; + lua_lock(L); + t = index2adr(L, idx); + api_checkvalidindex(L, t); + setsvalue(L, &key, luaS_new(L, k)); + luaV_gettable(L, t, &key, L->top); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_rawget (lua_State *L, int idx) { + StkId t; + lua_lock(L); + t = index2adr(L, idx); + api_check(L, ttistable(t)); + setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1)); + lua_unlock(L); +} + + +LUA_API void lua_rawgeti (lua_State *L, int idx, int n) { + StkId o; + lua_lock(L); + o = index2adr(L, idx); + api_check(L, ttistable(o)); + setobj2s(L, L->top, luaH_getnum(hvalue(o), n)); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API void lua_createtable (lua_State *L, int narray, int nrec) { + lua_lock(L); + luaC_checkGC(L); + sethvalue(L, L->top, luaH_new(L, narray, nrec)); + api_incr_top(L); + lua_unlock(L); +} + + +LUA_API int lua_getmetatable (lua_State *L, int objindex) { + const TValue *obj; + Table *mt = NULL; + int res; + lua_lock(L); + obj = index2adr(L, objindex); + switch (ttype(obj)) { + case LUA_TTABLE: + mt = hvalue(obj)->metatable; + break; + case LUA_TUSERDATA: + mt = uvalue(obj)->metatable; + break; + default: + mt = G(L)->mt[ttype(obj)]; + break; + } + if (mt == NULL) + res = 0; + else { + sethvalue(L, L->top, mt); + api_incr_top(L); + res = 1; + } + lua_unlock(L); + return res; +} + + +LUA_API void lua_getfenv (lua_State *L, int idx) { + StkId o; + lua_lock(L); + o = index2adr(L, idx); + api_checkvalidindex(L, o); + switch (ttype(o)) { + case LUA_TFUNCTION: + sethvalue(L, L->top, clvalue(o)->c.env); + break; + case LUA_TUSERDATA: + sethvalue(L, L->top, uvalue(o)->env); + break; + case LUA_TTHREAD: + setobj2s(L, L->top, gt(thvalue(o))); + break; + default: + setnilvalue(L->top); + break; + } + api_incr_top(L); + lua_unlock(L); +} + + +/* +** set functions (stack -> Lua) +*/ + + +LUA_API void lua_settable (lua_State *L, int idx) { + StkId t; + lua_lock(L); + api_checknelems(L, 2); + t = index2adr(L, idx); + api_checkvalidindex(L, t); + luaV_settable(L, t, L->top - 2, L->top - 1); + L->top -= 2; /* pop index and value */ + lua_unlock(L); +} + + +LUA_API void lua_setfield (lua_State *L, int idx, const char *k) { + StkId t; + TValue key; + lua_lock(L); + api_checknelems(L, 1); + t = index2adr(L, idx); + api_checkvalidindex(L, t); + setsvalue(L, &key, luaS_new(L, k)); + luaV_settable(L, t, &key, L->top - 1); + L->top--; /* pop value */ + lua_unlock(L); +} + + +LUA_API void lua_rawset (lua_State *L, int idx) { + StkId t; + lua_lock(L); + api_checknelems(L, 2); + t = index2adr(L, idx); + api_check(L, ttistable(t)); + setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1); + luaC_barriert(L, hvalue(t), L->top-1); + L->top -= 2; + lua_unlock(L); +} + + +LUA_API void lua_rawseti (lua_State *L, int idx, int n) { + StkId o; + lua_lock(L); + api_checknelems(L, 1); + o = index2adr(L, idx); + api_check(L, ttistable(o)); + setobj2t(L, luaH_setnum(L, hvalue(o), n), L->top-1); + luaC_barriert(L, hvalue(o), L->top-1); + L->top--; + lua_unlock(L); +} + + +LUA_API int lua_setmetatable (lua_State *L, int objindex) { + TValue *obj; + Table *mt; + lua_lock(L); + api_checknelems(L, 1); + obj = index2adr(L, objindex); + api_checkvalidindex(L, obj); + if (ttisnil(L->top - 1)) + mt = NULL; + else { + api_check(L, ttistable(L->top - 1)); + mt = hvalue(L->top - 1); + } + switch (ttype(obj)) { + case LUA_TTABLE: { + hvalue(obj)->metatable = mt; + if (mt) + luaC_objbarriert(L, hvalue(obj), mt); + break; + } + case LUA_TUSERDATA: { + uvalue(obj)->metatable = mt; + if (mt) + luaC_objbarrier(L, rawuvalue(obj), mt); + break; + } + default: { + G(L)->mt[ttype(obj)] = mt; + break; + } + } + L->top--; + lua_unlock(L); + return 1; +} + + +LUA_API int lua_setfenv (lua_State *L, int idx) { + StkId o; + int res = 1; + lua_lock(L); + api_checknelems(L, 1); + o = index2adr(L, idx); + api_checkvalidindex(L, o); + api_check(L, ttistable(L->top - 1)); + switch (ttype(o)) { + case LUA_TFUNCTION: + clvalue(o)->c.env = hvalue(L->top - 1); + break; + case LUA_TUSERDATA: + uvalue(o)->env = hvalue(L->top - 1); + break; + case LUA_TTHREAD: + sethvalue(L, gt(thvalue(o)), hvalue(L->top - 1)); + break; + default: + res = 0; + break; + } + if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1)); + L->top--; + lua_unlock(L); + return res; +} + + +/* +** `load' and `call' functions (run Lua code) +*/ + + +#define adjustresults(L,nres) \ + { if (nres == LUA_MULTRET && L->top >= L->ci->top) L->ci->top = L->top; } + + +#define checkresults(L,na,nr) \ + api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na))) + + +LUA_API void lua_call (lua_State *L, int nargs, int nresults) { + StkId func; + lua_lock(L); + api_checknelems(L, nargs+1); + checkresults(L, nargs, nresults); + func = L->top - (nargs+1); + luaD_call(L, func, nresults); + adjustresults(L, nresults); + lua_unlock(L); +} + + + +/* +** Execute a protected call. +*/ +struct CallS { /* data to `f_call' */ + StkId func; + int nresults; +}; + + +static void f_call (lua_State *L, void *ud) { + struct CallS *c = cast(struct CallS *, ud); + luaD_call(L, c->func, c->nresults); +} + + + +LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) { + struct CallS c; + int status; + ptrdiff_t func; + lua_lock(L); + api_checknelems(L, nargs+1); + checkresults(L, nargs, nresults); + if (errfunc == 0) + func = 0; + else { + StkId o = index2adr(L, errfunc); + api_checkvalidindex(L, o); + func = savestack(L, o); + } + c.func = L->top - (nargs+1); /* function to be called */ + c.nresults = nresults; + status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func); + adjustresults(L, nresults); + lua_unlock(L); + return status; +} + + +/* +** Execute a protected C call. +*/ +struct CCallS { /* data to `f_Ccall' */ + lua_CFunction func; + void *ud; +}; + + +static void f_Ccall (lua_State *L, void *ud) { + struct CCallS *c = cast(struct CCallS *, ud); + Closure *cl; + cl = luaF_newCclosure(L, 0, getcurrenv(L)); + cl->c.f = c->func; + setclvalue(L, L->top, cl); /* push function */ + api_incr_top(L); + setpvalue(L->top, c->ud); /* push only argument */ + api_incr_top(L); + luaD_call(L, L->top - 2, 0); +} + + +LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) { + struct CCallS c; + int status; + lua_lock(L); + c.func = func; + c.ud = ud; + status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0); + lua_unlock(L); + return status; +} + + +LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data, + const char *chunkname) { + ZIO z; + int status; + lua_lock(L); + if (!chunkname) chunkname = "?"; + luaZ_init(L, &z, reader, data); + status = luaD_protectedparser(L, &z, chunkname); + lua_unlock(L); + return status; +} + + +LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data) { + int status; + TValue *o; + lua_lock(L); + api_checknelems(L, 1); + o = L->top - 1; + if (isLfunction(o)) + status = luaU_dump(L, clvalue(o)->l.p, writer, data, 0); + else + status = 1; + lua_unlock(L); + return status; +} + + +LUA_API int lua_status (lua_State *L) { + return L->status; +} + + +/* +** Garbage-collection function +*/ + +LUA_API int lua_gc (lua_State *L, int what, int data) { + int res = 0; + global_State *g; + lua_lock(L); + g = G(L); + switch (what) { + case LUA_GCSTOP: { + g->GCthreshold = MAX_LUMEM; + break; + } + case LUA_GCRESTART: { + g->GCthreshold = g->totalbytes; + break; + } + case LUA_GCCOLLECT: { + luaC_fullgc(L); + break; + } + case LUA_GCCOUNT: { + /* GC values are expressed in Kbytes: #bytes/2^10 */ + res = cast_int(g->totalbytes >> 10); + break; + } + case LUA_GCCOUNTB: { + res = cast_int(g->totalbytes & 0x3ff); + break; + } + case LUA_GCSTEP: { + lu_mem a = (cast(lu_mem, data) << 10); + if (a <= g->totalbytes) + g->GCthreshold = g->totalbytes - a; + else + g->GCthreshold = 0; + while (g->GCthreshold <= g->totalbytes) { + luaC_step(L); + if (g->gcstate == GCSpause) { /* end of cycle? */ + res = 1; /* signal it */ + break; + } + } + break; + } + case LUA_GCSETPAUSE: { + res = g->gcpause; + g->gcpause = data; + break; + } + case LUA_GCSETSTEPMUL: { + res = g->gcstepmul; + g->gcstepmul = data; + break; + } + default: res = -1; /* invalid option */ + } + lua_unlock(L); + return res; +} + + + +/* +** miscellaneous functions +*/ + + +LUA_API int lua_error (lua_State *L) { + lua_lock(L); + api_checknelems(L, 1); + luaG_errormsg(L); + lua_unlock(L); + return 0; /* to avoid warnings */ +} + + +LUA_API int lua_next (lua_State *L, int idx) { + StkId t; + int more; + lua_lock(L); + t = index2adr(L, idx); + api_check(L, ttistable(t)); + more = luaH_next(L, hvalue(t), L->top - 1); + if (more) { + api_incr_top(L); + } + else /* no more elements */ + L->top -= 1; /* remove key */ + lua_unlock(L); + return more; +} + + +LUA_API void lua_concat (lua_State *L, int n) { + lua_lock(L); + api_checknelems(L, n); + if (n >= 2) { + luaC_checkGC(L); + luaV_concat(L, n, cast_int(L->top - L->base) - 1); + L->top -= (n-1); + } + else if (n == 0) { /* push empty string */ + setsvalue2s(L, L->top, luaS_newlstr(L, "", 0)); + api_incr_top(L); + } + /* else n == 1; nothing to do */ + lua_unlock(L); +} + + +LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) { + lua_Alloc f; + lua_lock(L); + if (ud) *ud = G(L)->ud; + f = G(L)->frealloc; + lua_unlock(L); + return f; +} + + +LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) { + lua_lock(L); + G(L)->ud = ud; + G(L)->frealloc = f; + lua_unlock(L); +} + + +LUA_API void *lua_newuserdata (lua_State *L, size_t size) { + Udata *u; + lua_lock(L); + luaC_checkGC(L); + u = luaS_newudata(L, size, getcurrenv(L)); + setuvalue(L, L->top, u); + api_incr_top(L); + lua_unlock(L); + return u + 1; +} + + + + +static const char *aux_upvalue (StkId fi, int n, TValue **val) { + Closure *f; + if (!ttisfunction(fi)) return NULL; + f = clvalue(fi); + if (f->c.isC) { + if (!(1 <= n && n <= f->c.nupvalues)) return NULL; + *val = &f->c.upvalue[n-1]; + return ""; + } + else { + Proto *p = f->l.p; + if (!(1 <= n && n <= p->sizeupvalues)) return NULL; + *val = f->l.upvals[n-1]->v; + return getstr(p->upvalues[n-1]); + } +} + + +LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) { + const char *name; + TValue *val; + lua_lock(L); + name = aux_upvalue(index2adr(L, funcindex), n, &val); + if (name) { + setobj2s(L, L->top, val); + api_incr_top(L); + } + lua_unlock(L); + return name; +} + + +LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) { + const char *name; + TValue *val; + StkId fi; + lua_lock(L); + fi = index2adr(L, funcindex); + api_checknelems(L, 1); + name = aux_upvalue(fi, n, &val); + if (name) { + L->top--; + setobj(L, val, L->top); + luaC_barrier(L, clvalue(fi), L->top); + } + lua_unlock(L); + return name; +} + |