aboutsummaryrefslogtreecommitdiff
path: root/src/lstate.js
blob: 9a9c9e016aa734e3421966588c47a8f013d02ea8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
/*jshint esversion: 6 */
"use strict";

const assert               = require('assert');

const lua                  = require('./lua.js');
const lobject              = require('./lobject.js');
const ldo                  = require('./ldo.js');
const lapi                 = require('./lapi.js');
const nil                  = ldo.nil;
const luaD_rawrunprotected = ldo.luaD_rawrunprotected;
const luaT_init            = require('./ltm.js').luaT_init;
const CT                   = lua.constant_types;
const LUA_MULTRET          = lua.LUA_MULTRET;
const TS                   = lua.thread_status;
const LUA_NUMTAGS          = lua.LUA_NUMTAGS;

const BASIC_STACK_SIZE = 2 * lua.LUA_MINSTACK;

class CallInfo {

    constructor(funcOff, func, top, base, previous, next) {
        this.func = func;
        this.funcOff = funcOff;
        this.top = top;
        this.previous = previous;
        this.next = next;
        this.pcOff = 0;
        this.u = {
            l: {  /* only for Lua functions */
                base: base,  /* base for this function */
                savedpc: []
            },
            c: {  /* only for JS functions */
                k: null,  /* continuation in case of yields */
                old_errfunc: null,
                ctx: null  /* context info. in case of yields */
            }
        };
        this.nresults = 0;
        this.callstatus = 0;
    }

}

class lua_State extends lobject.TValue {

    constructor() {
        super(CT.LUA_TTHREAD, null);
        this.base_ci = new CallInfo(); // Will be populated later
        this.top = 0;
        this.ci = null;
        this.ciOff = null;
        this.stack = [];
        this.openupval = [];
        this.status = TS.LUA_OK;
        this.next = null;
        this.twups = [this];
        this.errorJmp = null;
        this.nny = 1;
        this.errfunc = 0;

        this.value = this;
    }

}

class global_State {

    constructor(L) {
        this.mainthread = L;
        this.strt = null // TODO: string hash table
        this.l_registry = nil;
        this.panic = null;
        this.version = null;
        this.twups = [];
        this.mt = new Array(LUA_NUMTAGS);
    }

}


const stack_init = function(L1, L) {
    L1.stack = new Array(BASIC_STACK_SIZE); // TODO: for now we don't care about the stack size
    L1.top = 0;
    let ci = L1.base_ci;
    ci.next = ci.previous = null;
    ci.callstatus = 0;
    ci.func = L1.stack[L1.top];
    ci.funcOff = L1.top;
    L1.stack[L1.top++] = nil;
    ci.top = L1.top + lua.LUA_MINSTACK;
    L1.ci = ci;
};

/*
** Create registry table and its predefined values
*/
const init_registry = function(L, g) {
    let registry = new lobject.Table();
    g.l_registry = registry;
    registry.value.set(lua.LUA_RIDX_MAINTHREAD - 1, L);
    registry.value.set(lua.LUA_RIDX_GLOBALS - 1, new lobject.Table());
};

/*
** open parts of the state that may cause memory-allocation errors.
** ('g->version' != NULL flags that the state was completely build)
*/
const f_luaopen = function(L) {
    let g = L.l_G;
    stack_init(L, L);
    init_registry(L, g);
    // TODO: luaS_init(L);
    luaT_init(L);
    g.version = lapi.lua_version(null);
};

const preinit_thread = function(L, g) {
    L.l_G = g;
    L.stack = [];
    L.ci = null;
    L.nci = 0;
    L.twups = [L];  /* thread has no upvalues */
    L.errorJmp = null;
    L.nCcalls = 0;
    L.hook = null;
    L.hookmask = 0;
    L.basehookcount = 0;
    L.allowhook = 1;
    L.hookcount = L.basehookcount;
    L.openupval = [];
    L.nny = 1;
    L.status = TS.LUA_OK;
    L.errfunc = 0;
};

const lua_newthread = function(L) {
    let g = L.l_G;
    let L1 = new lua_State();
    L.stack[L.top++] = L1;
    assert(L.top <= L.ci.top, "stack overflow");
    preinit_thread(L1, g);
    L1.hookmask = L.hookmask;
    L1.basehookcount = L.basehookcount;
    L1.hook = L.hook;
    L1.hookcount = L1.basehookcount;
    stack_init(L1, L);
    return L1;
};

const lua_newstate = function() {
    let L = new lua_State();
    let g = new global_State(L);

    preinit_thread(L, g);

    if (luaD_rawrunprotected(L, f_luaopen, null) !== TS.LUA_OK) {
        L = null;
    }

    return L;
};

module.exports.lua_State      = lua_State;
module.exports.CallInfo       = CallInfo;
module.exports.CIST_OAH       = (1<<0);  /* original value of 'allowhook' */
module.exports.CIST_LUA       = (1<<1);  /* call is running a Lua function */
module.exports.CIST_HOOKED    = (1<<2);  /* call is running a debug hook */
module.exports.CIST_FRESH     = (1<<3);  /* call is running on a fresh invocation of luaV_execute */
module.exports.CIST_YPCALL    = (1<<4);  /* call is a yieldable protected call */
module.exports.CIST_TAIL      = (1<<5);  /* call was tail called */
module.exports.CIST_HOOKYIELD = (1<<6);  /* last hook called yielded */
module.exports.CIST_LEQ       = (1<<7);  /* using __lt for __le */
module.exports.CIST_FIN       = (1<<8);   /* call is running a finalizer */
module.exports.lua_newstate   = lua_newstate;
module.exports.lua_newthread  = lua_newthread;