diff options
Diffstat (limited to 'src/lvm.js')
| -rw-r--r-- | src/lvm.js | 128 |
1 files changed, 101 insertions, 27 deletions
@@ -19,6 +19,7 @@ const lstate = require('./lstate.js'); const CallInfo = lstate.CallInfo; const llimit = require('./llimit.js'); const ldo = require('./ldo.js'); +const nil = ldo.nil; const ltm = require('./ltm.js'); const ltable = require('./ltable.js'); const TMS = ltm.TMS; @@ -91,7 +92,7 @@ const luaV_execute = function(L) { } case "OP_LOADNIL": { for (let j = 0; j <= i.B; j++) - L.stack[ra + j] = ldo.nil; + L.stack[ra + j] = nil; break; } case "OP_GETUPVAL": { @@ -106,11 +107,8 @@ const luaV_execute = function(L) { let table = cl.upvals[i.B].val(L); let key = RKC(L, base, k, i); - // if (!table.ttistable() || !table.__index(table, key)) { - // // __index - // } else { - L.stack[ra] = table.__index(table, key); - // } + gettable(L, table, key, ra); + base = ci.u.l.base; break; } case "OP_SETTABUP": { @@ -118,11 +116,8 @@ const luaV_execute = function(L) { let key = RKB(L, base, k, i); let v = RKC(L, base, k, i); - // if (!table.ttistable() || !table.__index(table, key)) { - // // __index - // } else { - table.__newindex(table, key, v); - // } + settable(L, table, key, v); + base = ci.u.l.base; break; } @@ -130,11 +125,8 @@ const luaV_execute = function(L) { let table = RKB(L, base, k, i); let key = RKC(L, base, k, i); - // if (!table.ttistable() || !table.__index(table, key)) { - // // __index - // } else { - L.stack[ra] = table.__index(table, key); - // } + gettable(L, table, key, ra); + base = ci.u.l.base; break; } case "OP_SETTABLE": { @@ -142,11 +134,8 @@ const luaV_execute = function(L) { let key = RKB(L, base, k, i); let v = RKC(L, base, k, i); - // if (!table.ttistable() || !table.__index(table, key)) { - // // __index - // } else { - table.__newindex(table, key, v); - // } + settable(L, table, key, v); + base = ci.u.l.base; break; } @@ -160,11 +149,8 @@ const luaV_execute = function(L) { L.stack[ra + 1] = table; - // if (!table.ttistable() || !table.__index(table, key)) { - // // __index - // } else { - L.stack[ra] = table.__index(table, key); - // } + gettable(L, table, key, ra); + base = ci.u.l.base; break; } @@ -646,7 +632,7 @@ const luaV_execute = function(L) { L.stack[ra + j] = L.stack[base - n + j]; for (; j < b; j++) /* complete required results with nil */ - L.stack[ra + j] = ldo.nil; + L.stack[ra + j] = nil; break; } case "OP_EXTRAARG": { @@ -937,6 +923,94 @@ const luaV_concat = function(L, total) { } while (total > 1); /* repeat until only 1 result left */ }; +const MAXTAGRECUR = 2000; + +const gettable = function(L, table, key, ra, recur) { + recur = recur ? recur : 0; + + if (recur >= MAXTAGRECUR) + throw new Error("'__index' chain too long; possible loop"); // TODO: luaG_runerror + + if (table.ttistable()) { + let element = table.__index(table, key); + + if (!element.ttisnil()) { + L.stack[ra] = table.__index(table, key); + } else { + luaV_finishget(L, table, key, ra, element, recur); + } + } else { + luaV_finishget(L, table, key, ra, null, recur); + } +}; + +const luaV_finishget = function(L, t, key, val, slot, recur) { + let tm; + if (slot === null) { /* 't' is not a table? */ + assert(!t.ttistable()); + tm = ltm.luaT_gettmbyobj(L, t, TMS.TM_INDEX); + if (tm.ttisnil()) + throw new Error(`attempt to index a ${tm.ttype()} value`); // TODO: luaG_typeerror + } else { /* 't' is a table */ + assert(slot.ttisnil()); + tm = ltm.luaT_gettmbyobj(L, t, TMS.TM_INDEX); // TODO: fasttm + if (tm.ttisnil()) { + L.stack[val] = nil; + return; + } + } + + if (tm.ttisfunction()) { + ltm.luaT_callTM(L, tm, t, key, val, 1); + return; + } + + gettable(L, tm, key, val, recur + 1); +}; + +const settable = function(L, table, key, v, recur) { + recur = recur ? recur : 0; + + if (recur >= MAXTAGRECUR) + throw new Error("'__newindex' chain too long; possible loop"); // TODO: luaG_runerror + + if (table.ttistable()) { + let element = table.__index(table, key); + + if (!element.ttisnil()) { + table.__newindex(table, key, v); + } else { + luaV_finishset(L, table, key, v, element, recur); + } + } else { + luaV_finishset(L, table, key, v, null, recur); + } +}; + +const luaV_finishset = function(L, t, key, val, slot, recur) { + let tm; + if (slot !== null) { /* is 't' a table? */ + assert(slot.ttisnil()); + tm = ltm.luaT_gettmbyobj(L, t, TMS.TM_NEWINDEX); // TODO: fasttm + if (tm.ttisnil()) { + t.__newindex(t, key, val); + return; + } + } else { /* not a table; check metamethod */ + tm = ltm.luaT_gettmbyobj(L, t, TMS.TM_NEWINDEX); + if (tm.ttisnil()) + throw new Error(`attempt to index a ${tm.ttype()} value`); // TODO: luaG_typeerror + } + + if (tm.ttisfunction()) { + ltm.luaT_callTM(L, tm, t, key, val, 1); + return; + } + + settable(L, tm, key, val, recur + 1); +} + + module.exports.RA = RA; module.exports.RB = RB; module.exports.RC = RC; |