2 ** $Id: lcorolib.c,v 1.5.1.1 2013/04/12 18:48:47 roberto Exp $
4 ** See Copyright Notice in lua.h
20 static int auxresume (lua_State *L, lua_State *co, int narg) {
22 if (!lua_checkstack(co, narg)) {
23 lua_pushliteral(L, "too many arguments to resume");
24 return -1; /* error flag */
26 if (lua_status(co) == LUA_OK && lua_gettop(co) == 0) {
27 lua_pushliteral(L, "cannot resume dead coroutine");
28 return -1; /* error flag */
30 lua_xmove(L, co, narg);
31 status = lua_resume(co, L, narg);
32 if (status == LUA_OK || status == LUA_YIELD) {
33 int nres = lua_gettop(co);
34 if (!lua_checkstack(L, nres + 1)) {
35 lua_pop(co, nres); /* remove results anyway */
36 lua_pushliteral(L, "too many results to resume");
37 return -1; /* error flag */
39 lua_xmove(co, L, nres); /* move yielded values */
43 lua_xmove(co, L, 1); /* move error message */
44 return -1; /* error flag */
49 static int luaB_coresume (lua_State *L) {
50 lua_State *co = lua_tothread(L, 1);
52 luaL_argcheck(L, co, 1, "coroutine expected");
53 r = auxresume(L, co, lua_gettop(L) - 1);
55 lua_pushboolean(L, 0);
57 return 2; /* return false + error message */
60 lua_pushboolean(L, 1);
61 lua_insert(L, -(r + 1));
62 return r + 1; /* return true + `resume' returns */
67 static int luaB_auxwrap (lua_State *L) {
68 lua_State *co = lua_tothread(L, lua_upvalueindex(1));
69 int r = auxresume(L, co, lua_gettop(L));
71 if (lua_isstring(L, -1)) { /* error object is a string? */
72 luaL_where(L, 1); /* add extra info */
76 return lua_error(L); /* propagate error */
82 static int luaB_cocreate (lua_State *L) {
84 luaL_checktype(L, 1, LUA_TFUNCTION);
85 NL = lua_newthread(L);
86 lua_pushvalue(L, 1); /* move function to top */
87 lua_xmove(L, NL, 1); /* move function from L to NL */
92 static int luaB_cowrap (lua_State *L) {
94 lua_pushcclosure(L, luaB_auxwrap, 1);
99 static int luaB_yield (lua_State *L) {
100 return lua_yield(L, lua_gettop(L));
104 static int luaB_costatus (lua_State *L) {
105 lua_State *co = lua_tothread(L, 1);
106 luaL_argcheck(L, co, 1, "coroutine expected");
107 if (L == co) lua_pushliteral(L, "running");
109 switch (lua_status(co)) {
111 lua_pushliteral(L, "suspended");
115 if (lua_getstack(co, 0, &ar) > 0) /* does it have frames? */
116 lua_pushliteral(L, "normal"); /* it is running */
117 else if (lua_gettop(co) == 0)
118 lua_pushliteral(L, "dead");
120 lua_pushliteral(L, "suspended"); /* initial state */
123 default: /* some error occurred */
124 lua_pushliteral(L, "dead");
132 static int luaB_corunning (lua_State *L) {
133 int ismain = lua_pushthread(L);
134 lua_pushboolean(L, ismain);
139 static const luaL_Reg co_funcs[] = {
140 {"create", luaB_cocreate},
141 {"resume", luaB_coresume},
142 {"running", luaB_corunning},
143 {"status", luaB_costatus},
144 {"wrap", luaB_cowrap},
145 {"yield", luaB_yield},
151 LUAMOD_API int luaopen_coroutine (lua_State *L) {
152 luaL_newlib(L, co_funcs);