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
178
179
180
181
182
183
184
185
186
187
188
189
190
|
/*jshint esversion: 6 */
"use strict";
const lua = require('./lua.js');
const CT = lua.constant_types;
const LUA_MULTRET = lua.LUA_MULTRET;
const lobject = require('./lobject.js');
const TValue = lobject.TValue;
const lstate = require('./lstate.js');
const CallInfo = lstate.CallInfo;
const llimit = require('./llimit.js');
const ltm = require('./ltm.js');
const TMS = ltm.TMS;
const lvm = require('./lvm.js');
const nil = new TValue(CT.LUA_TNIL, null);
const luaD_precall = function(L, off, nresults) {
let func = L.stack[off];
let ci;
switch(func.type) {
case CT.LUA_TCCL: // JS function ?
throw new Error("LUA_TCCL not implemeted yet");
case CT.LUA_TLCF: // still JS function ?
throw new Error("LUA_TLCF not implemeted yet");
case CT.LUA_TLCL: {
let p = func.p;
let n = L.top - off - 1;
let fsize = p.maxstacksize;
let base;
if (p.is_vararg) {
base = adjust_varargs(L, p, n);
} else {
for (; n < p.numparams; n++)
L.stack[L.top++] = nil; // complete missing arguments
base = off + 1;
}
// next_ci
if (L.ci.next) {
L.ci = L.ci.next;
ci = L.ci;
} else {
ci = new CallInfo(off);
L.ci.next = ci;
ci.previous = L.ci;
ci.next = null;
L.ci = ci;
L.ciOff++;
}
ci.nresults = nresults;
ci.func = func;
ci.funcOff = off;
ci.u.l.base = base;
ci.top = base + fsize;
L.top = ci.top;
ci.u.l.savedpc = p.code;
ci.pcOff = 0;
ci.callstatus = lstate.CIST_LUA;
return false;
}
default:
tryfuncTM(L, off, func);
return luaD_precall(L, off, nresults);
}
};
const luaD_poscall = function(L, ci, firstResult, nres) {
let wanted = ci.nresults;
let res = ci.funcOff;
L.ci = ci.previous;
L.ciOff--;
return moveresults(L, firstResult, res, nres, wanted);
};
const moveresults = function(L, firstResult, res, nres, wanted) {
switch (wanted) {
case 0:
break;
case 1: {
if (nres === 0)
firstResult = nil;
L.stack[res] = L.stack[firstResult];
break;
}
case LUA_MULTRET: {
for (let i = 0; i < nres; i++)
L.stack[res + i] = L.stack[firstResult + i];
L.top = res + nres;
return false;
}
default: {
let i;
if (wanted <= nres) {
for (i = 0; i < wanted; i++) {
L.stack[res + i] = L.stack[firstResult + i];
}
} else {
for (i = 0; i < nres; i++)
L.stack[res + i] = L.stack[firstResult + i];
for (; i < wanted; i++)
L.stack[res + i] = nil;
}
break;
}
}
L.top = res + wanted; /* top points after the last result */
return true;
};
const adjust_varargs = function(L, p, actual) {
let nfixargs = p.numparams;
/* move fixed parameters to final position */
let fixed = L.top - actual; /* first fixed argument */
let base = L.top; /* final position of first argument */
let i;
for (i = 0; i < nfixargs && i < actual; i++) {
L.stack[L.top++] = L.stack[fixed + i];
L.stack[fixed + i] = nil;
}
for (; i < nfixargs; i++)
L.stack[L.top++] = nil;
return base;
};
const tryfuncTM = function(L, off, func) {
let tm = ltm.luaT_gettmbyobj(L, func, TMS.TM_CALL);
if (!tm.ttisfunction(tm))
throw new Error("__call metatable member is not a function"); // TODO: luaG_typeerror
/* Open a hole inside the stack at 'func' */
for (let p = L.top; p > off; p--)
L.stack[p] = L.stack[p-1];
L.top++; /* slot ensured by caller */
L.stack[off] = tm; /* tag method is the new function to be called */
};
/*
** Check appropriate error for stack overflow ("regular" overflow or
** overflow while handling stack overflow). If 'nCalls' is larger than
** LUAI_MAXCCALLS (which means it is handling a "regular" overflow) but
** smaller than 9/8 of LUAI_MAXCCALLS, does not report an error (to
** allow overflow handling to work)
*/
const stackerror = function(L) {
if (L.nCcalls === llimit.LUAI_MAXCCALLS)
throw new Error("JS stack overflow");
else if (L.nCcalls >= llimit.LUAI_MAXCCALLS + (llimit.LUAI_MAXCCALLS >> 3)) /* error while handing stack error */
throw new Error("stack overflow"); // TODO: luaD_throw(L, LUA_ERRERR);
};
/*
** Call a function (JS or Lua). The function to be called is at func.
** The arguments are on the stack, right after the function.
** When returns, all the results are on the stack, starting at the original
** function position.
*/
const luaD_call = function(L, off, nResults) {
if (++L.nCcalls >= llimit.LUAI_MAXCCALLS)
stackerror(L);
if (!luaD_precall(L, off, nResults))
lvm.luaV_execute(L);
L.nCcalls--;
};
/*
** Similar to 'luaD_call', but does not allow yields during the call
*/
const luaD_callnoyield = function(L, off, nResults) {
L.nny++;
luaD_call(L, off, nResults);
L.nny--;
};
module.exports.nil = nil;
module.exports.luaD_precall = luaD_precall;
module.exports.luaD_poscall = luaD_poscall;
module.exports.moveresults = moveresults;
module.exports.adjust_varargs = adjust_varargs;
module.exports.tryfuncTM = tryfuncTM;
module.exports.stackerror = stackerror;
module.exports.luaD_call = luaD_call;
module.exports.luaD_callnoyield = luaD_callnoyield;
|
