1*dfc11533SChris Williamson /*
2*dfc11533SChris Williamson ** $Id: lcorolib.c,v 1.5.1.1 2013/04/12 18:48:47 roberto Exp $
3*dfc11533SChris Williamson ** Coroutine Library
4*dfc11533SChris Williamson ** See Copyright Notice in lua.h
5*dfc11533SChris Williamson */
6*dfc11533SChris Williamson
7*dfc11533SChris Williamson
8*dfc11533SChris Williamson #include <sys/zfs_context.h>
9*dfc11533SChris Williamson
10*dfc11533SChris Williamson #define lcorolib_c
11*dfc11533SChris Williamson #define LUA_LIB
12*dfc11533SChris Williamson
13*dfc11533SChris Williamson #include "lua.h"
14*dfc11533SChris Williamson
15*dfc11533SChris Williamson #include "lauxlib.h"
16*dfc11533SChris Williamson #include "lualib.h"
17*dfc11533SChris Williamson
18*dfc11533SChris Williamson
auxresume(lua_State * L,lua_State * co,int narg)19*dfc11533SChris Williamson static int auxresume (lua_State *L, lua_State *co, int narg) {
20*dfc11533SChris Williamson int status;
21*dfc11533SChris Williamson if (!lua_checkstack(co, narg)) {
22*dfc11533SChris Williamson lua_pushliteral(L, "too many arguments to resume");
23*dfc11533SChris Williamson return -1; /* error flag */
24*dfc11533SChris Williamson }
25*dfc11533SChris Williamson if (lua_status(co) == LUA_OK && lua_gettop(co) == 0) {
26*dfc11533SChris Williamson lua_pushliteral(L, "cannot resume dead coroutine");
27*dfc11533SChris Williamson return -1; /* error flag */
28*dfc11533SChris Williamson }
29*dfc11533SChris Williamson lua_xmove(L, co, narg);
30*dfc11533SChris Williamson status = lua_resume(co, L, narg);
31*dfc11533SChris Williamson if (status == LUA_OK || status == LUA_YIELD) {
32*dfc11533SChris Williamson int nres = lua_gettop(co);
33*dfc11533SChris Williamson if (!lua_checkstack(L, nres + 1)) {
34*dfc11533SChris Williamson lua_pop(co, nres); /* remove results anyway */
35*dfc11533SChris Williamson lua_pushliteral(L, "too many results to resume");
36*dfc11533SChris Williamson return -1; /* error flag */
37*dfc11533SChris Williamson }
38*dfc11533SChris Williamson lua_xmove(co, L, nres); /* move yielded values */
39*dfc11533SChris Williamson return nres;
40*dfc11533SChris Williamson }
41*dfc11533SChris Williamson else {
42*dfc11533SChris Williamson lua_xmove(co, L, 1); /* move error message */
43*dfc11533SChris Williamson return -1; /* error flag */
44*dfc11533SChris Williamson }
45*dfc11533SChris Williamson }
46*dfc11533SChris Williamson
47*dfc11533SChris Williamson
luaB_coresume(lua_State * L)48*dfc11533SChris Williamson static int luaB_coresume (lua_State *L) {
49*dfc11533SChris Williamson lua_State *co = lua_tothread(L, 1);
50*dfc11533SChris Williamson int r;
51*dfc11533SChris Williamson luaL_argcheck(L, co, 1, "coroutine expected");
52*dfc11533SChris Williamson r = auxresume(L, co, lua_gettop(L) - 1);
53*dfc11533SChris Williamson if (r < 0) {
54*dfc11533SChris Williamson lua_pushboolean(L, 0);
55*dfc11533SChris Williamson lua_insert(L, -2);
56*dfc11533SChris Williamson return 2; /* return false + error message */
57*dfc11533SChris Williamson }
58*dfc11533SChris Williamson else {
59*dfc11533SChris Williamson lua_pushboolean(L, 1);
60*dfc11533SChris Williamson lua_insert(L, -(r + 1));
61*dfc11533SChris Williamson return r + 1; /* return true + `resume' returns */
62*dfc11533SChris Williamson }
63*dfc11533SChris Williamson }
64*dfc11533SChris Williamson
65*dfc11533SChris Williamson
luaB_auxwrap(lua_State * L)66*dfc11533SChris Williamson static int luaB_auxwrap (lua_State *L) {
67*dfc11533SChris Williamson lua_State *co = lua_tothread(L, lua_upvalueindex(1));
68*dfc11533SChris Williamson int r = auxresume(L, co, lua_gettop(L));
69*dfc11533SChris Williamson if (r < 0) {
70*dfc11533SChris Williamson if (lua_isstring(L, -1)) { /* error object is a string? */
71*dfc11533SChris Williamson luaL_where(L, 1); /* add extra info */
72*dfc11533SChris Williamson lua_insert(L, -2);
73*dfc11533SChris Williamson lua_concat(L, 2);
74*dfc11533SChris Williamson }
75*dfc11533SChris Williamson return lua_error(L); /* propagate error */
76*dfc11533SChris Williamson }
77*dfc11533SChris Williamson return r;
78*dfc11533SChris Williamson }
79*dfc11533SChris Williamson
80*dfc11533SChris Williamson
luaB_cocreate(lua_State * L)81*dfc11533SChris Williamson static int luaB_cocreate (lua_State *L) {
82*dfc11533SChris Williamson lua_State *NL;
83*dfc11533SChris Williamson luaL_checktype(L, 1, LUA_TFUNCTION);
84*dfc11533SChris Williamson NL = lua_newthread(L);
85*dfc11533SChris Williamson lua_pushvalue(L, 1); /* move function to top */
86*dfc11533SChris Williamson lua_xmove(L, NL, 1); /* move function from L to NL */
87*dfc11533SChris Williamson return 1;
88*dfc11533SChris Williamson }
89*dfc11533SChris Williamson
90*dfc11533SChris Williamson
luaB_cowrap(lua_State * L)91*dfc11533SChris Williamson static int luaB_cowrap (lua_State *L) {
92*dfc11533SChris Williamson luaB_cocreate(L);
93*dfc11533SChris Williamson lua_pushcclosure(L, luaB_auxwrap, 1);
94*dfc11533SChris Williamson return 1;
95*dfc11533SChris Williamson }
96*dfc11533SChris Williamson
97*dfc11533SChris Williamson
luaB_yield(lua_State * L)98*dfc11533SChris Williamson static int luaB_yield (lua_State *L) {
99*dfc11533SChris Williamson return lua_yield(L, lua_gettop(L));
100*dfc11533SChris Williamson }
101*dfc11533SChris Williamson
102*dfc11533SChris Williamson
luaB_costatus(lua_State * L)103*dfc11533SChris Williamson static int luaB_costatus (lua_State *L) {
104*dfc11533SChris Williamson lua_State *co = lua_tothread(L, 1);
105*dfc11533SChris Williamson luaL_argcheck(L, co, 1, "coroutine expected");
106*dfc11533SChris Williamson if (L == co) lua_pushliteral(L, "running");
107*dfc11533SChris Williamson else {
108*dfc11533SChris Williamson switch (lua_status(co)) {
109*dfc11533SChris Williamson case LUA_YIELD:
110*dfc11533SChris Williamson lua_pushliteral(L, "suspended");
111*dfc11533SChris Williamson break;
112*dfc11533SChris Williamson case LUA_OK: {
113*dfc11533SChris Williamson lua_Debug ar;
114*dfc11533SChris Williamson if (lua_getstack(co, 0, &ar) > 0) /* does it have frames? */
115*dfc11533SChris Williamson lua_pushliteral(L, "normal"); /* it is running */
116*dfc11533SChris Williamson else if (lua_gettop(co) == 0)
117*dfc11533SChris Williamson lua_pushliteral(L, "dead");
118*dfc11533SChris Williamson else
119*dfc11533SChris Williamson lua_pushliteral(L, "suspended"); /* initial state */
120*dfc11533SChris Williamson break;
121*dfc11533SChris Williamson }
122*dfc11533SChris Williamson default: /* some error occurred */
123*dfc11533SChris Williamson lua_pushliteral(L, "dead");
124*dfc11533SChris Williamson break;
125*dfc11533SChris Williamson }
126*dfc11533SChris Williamson }
127*dfc11533SChris Williamson return 1;
128*dfc11533SChris Williamson }
129*dfc11533SChris Williamson
130*dfc11533SChris Williamson
luaB_corunning(lua_State * L)131*dfc11533SChris Williamson static int luaB_corunning (lua_State *L) {
132*dfc11533SChris Williamson int ismain = lua_pushthread(L);
133*dfc11533SChris Williamson lua_pushboolean(L, ismain);
134*dfc11533SChris Williamson return 2;
135*dfc11533SChris Williamson }
136*dfc11533SChris Williamson
137*dfc11533SChris Williamson
138*dfc11533SChris Williamson static const luaL_Reg co_funcs[] = {
139*dfc11533SChris Williamson {"create", luaB_cocreate},
140*dfc11533SChris Williamson {"resume", luaB_coresume},
141*dfc11533SChris Williamson {"running", luaB_corunning},
142*dfc11533SChris Williamson {"status", luaB_costatus},
143*dfc11533SChris Williamson {"wrap", luaB_cowrap},
144*dfc11533SChris Williamson {"yield", luaB_yield},
145*dfc11533SChris Williamson {NULL, NULL}
146*dfc11533SChris Williamson };
147*dfc11533SChris Williamson
148*dfc11533SChris Williamson
149*dfc11533SChris Williamson
luaopen_coroutine(lua_State * L)150*dfc11533SChris Williamson LUAMOD_API int luaopen_coroutine (lua_State *L) {
151*dfc11533SChris Williamson luaL_newlib(L, co_funcs);
152*dfc11533SChris Williamson return 1;
153*dfc11533SChris Williamson }
154*dfc11533SChris Williamson
155