js_State *js_newstate(js_Alloc alloc, void *actx)
{
js_State *J;
if (!alloc)
alloc = js_defaultalloc;
J = alloc(actx, NULL, sizeof *J);
if (!J)
return NULL;
memset(J, 0, sizeof(*J));
J->actx = actx;
J->alloc = alloc;
J->panic = js_defaultpanic;
J->stack = alloc(actx, NULL, JS_STACKSIZE * sizeof *J->stack);
if (!J->stack) {
alloc(actx, NULL, 0);
return NULL;
}
J->gcmark = 1;
J->nextref = 0;
J->R = jsV_newobject(J, JS_COBJECT, NULL);
J->G = jsV_newobject(J, JS_COBJECT, NULL);
J->E = jsR_newenvironment(J, J->G, NULL);
J->GE = J->E;
jsB_init(J);
return J;
}
js_State *js_newstate(js_Alloc alloc, void *actx, int flags)
{
js_State *J;
assert(sizeof(js_Value) == 16);
assert(offsetof(js_Value, type) == 15);
if (!alloc)
alloc = js_defaultalloc;
J = alloc(actx, NULL, sizeof *J);
if (!J)
return NULL;
memset(J, 0, sizeof(*J));
J->actx = actx;
J->alloc = alloc;
if (flags & JS_STRICT)
J->strict = 1;
J->trace[0].name = "?";
J->trace[0].file = "[C]";
J->trace[0].line = 0;
J->panic = js_defaultpanic;
J->stack = alloc(actx, NULL, JS_STACKSIZE * sizeof *J->stack);
if (!J->stack) {
alloc(actx, NULL, 0);
return NULL;
}
J->gcmark = 1;
J->nextref = 0;
J->R = jsV_newobject(J, JS_COBJECT, NULL);
J->G = jsV_newobject(J, JS_COBJECT, NULL);
J->E = jsR_newenvironment(J, J->G, NULL);
J->GE = J->E;
jsB_init(J);
return J;
}
static void jsR_callfunction(js_State *J, unsigned int n, js_Function *F, js_Environment *scope)
{
js_Value v;
unsigned int i;
scope = jsR_newenvironment(J, jsV_newobject(J, JS_COBJECT, NULL), scope);
jsR_savescope(J, scope);
if (F->arguments) {
js_newobject(J);
if (!J->strict) {
js_currentfunction(J);
js_defproperty(J, -2, "callee", JS_DONTENUM);
}
js_pushnumber(J, n);
js_defproperty(J, -2, "length", JS_DONTENUM);
for (i = 0; i < n; ++i) {
js_copy(J, i + 1);
js_setindex(J, -2, i);
}
js_initvar(J, "arguments", -1);
js_pop(J, 1);
}
for (i = 0; i < F->numparams; ++i) {
if (i < n)
js_initvar(J, F->vartab[i], i + 1);
else {
js_pushundefined(J);
js_initvar(J, F->vartab[i], -1);
js_pop(J, 1);
}
}
js_pop(J, n);
jsR_run(J, F);
v = *stackidx(J, -1);
TOP = --BOT; /* clear stack */
js_pushvalue(J, v);
jsR_restorescope(J);
}
static void jsR_run(js_State *J, js_Function *F)
{
js_Function **FT = F->funtab;
double *NT = F->numtab;
const char **ST = F->strtab;
js_Instruction *pcstart = F->code;
js_Instruction *pc = F->code;
enum js_OpCode opcode;
int offset;
const char *str;
js_Object *obj;
double x, y;
unsigned int ux, uy;
int ix, iy, okay;
int b;
while (1) {
if (J->gccounter > JS_GCLIMIT) {
J->gccounter = 0;
js_gc(J, 0);
}
opcode = *pc++;
switch (opcode) {
case OP_POP: js_pop(J, 1); break;
case OP_DUP: js_dup(J); break;
case OP_DUP2: js_dup2(J); break;
case OP_ROT2: js_rot2(J); break;
case OP_ROT3: js_rot3(J); break;
case OP_ROT4: js_rot4(J); break;
case OP_NUMBER_0: js_pushnumber(J, 0); break;
case OP_NUMBER_1: js_pushnumber(J, 1); break;
case OP_NUMBER_POS: js_pushnumber(J, *pc++); break;
case OP_NUMBER_NEG: js_pushnumber(J, -(*pc++)); break;
case OP_NUMBER: js_pushnumber(J, NT[*pc++]); break;
case OP_STRING: js_pushliteral(J, ST[*pc++]); break;
case OP_CLOSURE: js_newfunction(J, FT[*pc++], J->E); break;
case OP_NEWOBJECT: js_newobject(J); break;
case OP_NEWARRAY: js_newarray(J); break;
case OP_NEWREGEXP: js_newregexp(J, ST[pc[0]], pc[1]); pc += 2; break;
case OP_UNDEF: js_pushundefined(J); break;
case OP_NULL: js_pushnull(J); break;
case OP_TRUE: js_pushboolean(J, 1); break;
case OP_FALSE: js_pushboolean(J, 0); break;
case OP_THIS: js_copy(J, 0); break;
case OP_GLOBAL: js_pushobject(J, J->G); break;
case OP_CURRENT: js_currentfunction(J); break;
case OP_INITLOCAL:
STACK[BOT + *pc++] = STACK[--TOP];
break;
case OP_GETLOCAL:
CHECKSTACK(1);
STACK[TOP++] = STACK[BOT + *pc++];
break;
case OP_SETLOCAL:
STACK[BOT + *pc++] = STACK[TOP-1];
break;
case OP_DELLOCAL:
++pc;
js_pushboolean(J, 0);
break;
case OP_INITVAR:
js_initvar(J, ST[*pc++], -1);
js_pop(J, 1);
break;
case OP_DEFVAR:
js_defvar(J, ST[*pc++]);
break;
case OP_GETVAR:
str = ST[*pc++];
if (!js_hasvar(J, str))
js_referenceerror(J, "'%s' is not defined", str);
break;
case OP_HASVAR:
if (!js_hasvar(J, ST[*pc++]))
js_pushundefined(J);
break;
case OP_SETVAR:
js_setvar(J, ST[*pc++]);
break;
case OP_DELVAR:
b = js_delvar(J, ST[*pc++]);
js_pushboolean(J, b);
break;
case OP_IN:
str = js_tostring(J, -2);
if (!js_isobject(J, -1))
js_typeerror(J, "operand to 'in' is not an object");
b = js_hasproperty(J, -1, str);
js_pop(J, 2 + b);
js_pushboolean(J, b);
break;
case OP_INITPROP:
obj = js_toobject(J, -3);
str = js_tostring(J, -2);
jsR_setproperty(J, obj, str, stackidx(J, -1));
js_pop(J, 2);
break;
case OP_INITGETTER:
obj = js_toobject(J, -3);
str = js_tostring(J, -2);
jsR_defproperty(J, obj, str, 0, NULL, jsR_tofunction(J, -1), NULL);
js_pop(J, 2);
break;
case OP_INITSETTER:
obj = js_toobject(J, -3);
str = js_tostring(J, -2);
jsR_defproperty(J, obj, str, 0, NULL, NULL, jsR_tofunction(J, -1));
js_pop(J, 2);
break;
case OP_GETPROP:
str = js_tostring(J, -1);
obj = js_toobject(J, -2);
jsR_getproperty(J, obj, str);
js_rot3pop2(J);
break;
case OP_GETPROP_S:
str = ST[*pc++];
obj = js_toobject(J, -1);
jsR_getproperty(J, obj, str);
js_rot2pop1(J);
break;
case OP_SETPROP:
str = js_tostring(J, -2);
obj = js_toobject(J, -3);
jsR_setproperty(J, obj, str, stackidx(J, -1));
js_rot3pop2(J);
break;
case OP_SETPROP_S:
str = ST[*pc++];
obj = js_toobject(J, -2);
jsR_setproperty(J, obj, str, stackidx(J, -1));
js_rot2pop1(J);
break;
case OP_DELPROP:
str = js_tostring(J, -1);
obj = js_toobject(J, -2);
b = jsR_delproperty(J, obj, str);
js_pop(J, 2);
js_pushboolean(J, b);
break;
case OP_DELPROP_S:
str = ST[*pc++];
obj = js_toobject(J, -1);
b = jsR_delproperty(J, obj, str);
js_pop(J, 1);
js_pushboolean(J, b);
break;
case OP_ITERATOR:
if (!js_isundefined(J, -1) && !js_isnull(J, -1)) {
obj = jsV_newiterator(J, js_toobject(J, -1), 0);
js_pop(J, 1);
js_pushobject(J, obj);
}
break;
case OP_NEXTITER:
obj = js_toobject(J, -1);
str = jsV_nextiterator(J, obj);
if (str) {
js_pushliteral(J, str);
js_pushboolean(J, 1);
} else {
js_pop(J, 1);
js_pushboolean(J, 0);
}
break;
/* Function calls */
case OP_EVAL:
js_eval(J);
break;
case OP_CALL:
js_call(J, *pc++);
break;
case OP_NEW:
js_construct(J, *pc++);
break;
/* Unary operators */
case OP_TYPEOF:
str = js_typeof(J, -1);
js_pop(J, 1);
js_pushliteral(J, str);
break;
case OP_POS:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, x);
break;
case OP_NEG:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, -x);
break;
case OP_BITNOT:
ix = js_toint32(J, -1);
js_pop(J, 1);
js_pushnumber(J, ~ix);
break;
case OP_LOGNOT:
b = js_toboolean(J, -1);
js_pop(J, 1);
js_pushboolean(J, !b);
break;
case OP_INC:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, x + 1);
break;
case OP_DEC:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, x - 1);
break;
case OP_POSTINC:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, x + 1);
js_pushnumber(J, x);
break;
case OP_POSTDEC:
x = js_tonumber(J, -1);
js_pop(J, 1);
js_pushnumber(J, x - 1);
js_pushnumber(J, x);
break;
/* Multiplicative operators */
case OP_MUL:
x = js_tonumber(J, -2);
y = js_tonumber(J, -1);
js_pop(J, 2);
js_pushnumber(J, x * y);
break;
case OP_DIV:
x = js_tonumber(J, -2);
y = js_tonumber(J, -1);
js_pop(J, 2);
js_pushnumber(J, x / y);
break;
case OP_MOD:
x = js_tonumber(J, -2);
y = js_tonumber(J, -1);
js_pop(J, 2);
js_pushnumber(J, fmod(x, y));
break;
/* Additive operators */
case OP_ADD:
js_concat(J);
break;
case OP_SUB:
x = js_tonumber(J, -2);
y = js_tonumber(J, -1);
js_pop(J, 2);
js_pushnumber(J, x - y);
break;
/* Shift operators */
case OP_SHL:
ix = js_toint32(J, -2);
uy = js_touint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ix << (uy & 0x1F));
break;
case OP_SHR:
ix = js_toint32(J, -2);
uy = js_touint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ix >> (uy & 0x1F));
break;
case OP_USHR:
ux = js_touint32(J, -2);
uy = js_touint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ux >> (uy & 0x1F));
break;
/* Relational operators */
case OP_LT: b = js_compare(J, &okay); js_pop(J, 2); js_pushboolean(J, okay && b < 0); break;
case OP_GT: b = js_compare(J, &okay); js_pop(J, 2); js_pushboolean(J, okay && b > 0); break;
case OP_LE: b = js_compare(J, &okay); js_pop(J, 2); js_pushboolean(J, okay && b <= 0); break;
case OP_GE: b = js_compare(J, &okay); js_pop(J, 2); js_pushboolean(J, okay && b >= 0); break;
case OP_INSTANCEOF:
b = js_instanceof(J);
js_pop(J, 2);
js_pushboolean(J, b);
break;
/* Equality */
case OP_EQ: b = js_equal(J); js_pop(J, 2); js_pushboolean(J, b); break;
case OP_NE: b = js_equal(J); js_pop(J, 2); js_pushboolean(J, !b); break;
case OP_STRICTEQ: b = js_strictequal(J); js_pop(J, 2); js_pushboolean(J, b); break;
case OP_STRICTNE: b = js_strictequal(J); js_pop(J, 2); js_pushboolean(J, !b); break;
case OP_JCASE:
offset = *pc++;
b = js_strictequal(J);
if (b) {
js_pop(J, 2);
pc = pcstart + offset;
} else {
js_pop(J, 1);
}
break;
/* Binary bitwise operators */
case OP_BITAND:
ix = js_toint32(J, -2);
iy = js_toint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ix & iy);
break;
case OP_BITXOR:
ix = js_toint32(J, -2);
iy = js_toint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ix ^ iy);
break;
case OP_BITOR:
ix = js_toint32(J, -2);
iy = js_toint32(J, -1);
js_pop(J, 2);
js_pushnumber(J, ix | iy);
break;
/* Try and Catch */
case OP_THROW:
js_throw(J);
case OP_TRY:
offset = *pc++;
if (js_trypc(J, pc)) {
pc = J->trybuf[J->trytop].pc;
} else {
pc = pcstart + offset;
}
break;
case OP_ENDTRY:
js_endtry(J);
break;
case OP_CATCH:
str = ST[*pc++];
obj = jsV_newobject(J, JS_COBJECT, NULL);
js_pushobject(J, obj);
js_rot2(J);
js_setproperty(J, -2, str);
J->E = jsR_newenvironment(J, obj, J->E);
js_pop(J, 1);
break;
case OP_ENDCATCH:
J->E = J->E->outer;
break;
/* With */
case OP_WITH:
obj = js_toobject(J, -1);
J->E = jsR_newenvironment(J, obj, J->E);
js_pop(J, 1);
break;
case OP_ENDWITH:
J->E = J->E->outer;
break;
/* Branching */
case OP_DEBUGGER:
js_trap(J, (int)(pc - pcstart) - 1);
break;
case OP_JUMP:
pc = pcstart + *pc;
break;
case OP_JTRUE:
offset = *pc++;
b = js_toboolean(J, -1);
js_pop(J, 1);
if (b)
pc = pcstart + offset;
break;
case OP_JFALSE:
offset = *pc++;
b = js_toboolean(J, -1);
js_pop(J, 1);
if (!b)
pc = pcstart + offset;
break;
case OP_RETURN:
return;
case OP_LINE:
J->trace[J->tracetop].line = *pc++;
break;
}
}
}