4 ////////////////////////////////////////////////////////////////////////
5 // Debugging stuff. ////////////////////////////////////////////////////
6 ////////////////////////////////////////////////////////////////////////
8 #if !defined(DEBUG_NASAL)
9 # define DBG(expr) /* noop */
11 # define DBG(expr) expr
15 char* opStringDEBUG(int op);
16 void printOpDEBUG(int ip, int op);
17 void printStackDEBUG(struct Context* ctx);
18 ////////////////////////////////////////////////////////////////////////
20 struct Globals* globals = 0;
22 static naRef bindFunction(struct Context* ctx, struct Frame* f, naRef code);
24 #define ERR(c, msg) naRuntimeError((c),(msg))
25 void naRuntimeError(struct Context* c, char* msg)
28 longjmp(c->jumpHandle, 1);
31 static int boolify(struct Context* ctx, naRef r)
33 if(IS_NUM(r)) return r.num != 0;
34 if(IS_NIL(r)) return 0;
37 if(naStr_len(r) == 0) return 0;
38 if(naStr_tonum(r, &d)) return d != 0;
41 ERR(ctx, "non-scalar used in boolean context");
45 static double numify(struct Context* ctx, naRef o)
48 if(IS_NUM(o)) return o.num;
49 else if(IS_NIL(o)) ERR(ctx, "nil used in numeric context");
50 else if(!IS_STR(o)) ERR(ctx, "non-scalar in numeric context");
51 else if(naStr_tonum(o, &n)) return n;
52 else ERR(ctx, "non-numeric string in numeric context");
56 static naRef stringify(struct Context* ctx, naRef r)
58 if(IS_STR(r)) return r;
59 if(IS_NUM(r)) return naStr_fromnum(naNewString(ctx), r.num);
60 ERR(ctx, "non-scalar in string context");
64 static int checkVec(struct Context* ctx, naRef vec, naRef idx)
66 int i = (int)numify(ctx, idx);
67 if(i < 0 || i >= vec.ref.ptr.vec->rec->size)
68 ERR(ctx, "vector index out of bounds");
72 static naRef containerGet(struct Context* ctx, naRef box, naRef key)
74 naRef result = naNil();
75 if(!IS_SCALAR(key)) ERR(ctx, "container index not scalar");
77 if(!naHash_get(box, key, &result))
78 ERR(ctx, "undefined value in container");
79 } else if(IS_VEC(box)) {
80 result = naVec_get(box, checkVec(ctx, box, key));
82 ERR(ctx, "extract from non-container");
87 static void containerSet(struct Context* ctx, naRef box, naRef key, naRef val)
89 if(!IS_SCALAR(key)) ERR(ctx, "container index not scalar");
90 else if(IS_HASH(box)) naHash_set(box, key, val);
91 else if(IS_VEC(box)) naVec_set(box, checkVec(ctx, box, key), val);
92 else ERR(ctx, "insert into non-container");
95 static void initContext(struct Context* c)
98 c->fTop = c->opTop = c->markTop = 0;
99 for(i=0; i<NUM_NASAL_TYPES; i++)
101 naVec_setsize(c->temps, 4);
108 static void initGlobals()
112 globals = (struct Globals*)naAlloc(sizeof(struct Globals));
113 naBZero(globals, sizeof(struct Globals));
115 globals->sem = naNewSem();
116 globals->lock = naNewLock();
118 globals->allocCount = 256; // reasonable starting value
119 for(i=0; i<NUM_NASAL_TYPES; i++)
120 naGC_init(&(globals->pools[i]), i);
121 globals->deadsz = 256;
123 globals->deadBlocks = naAlloc(sizeof(void*) * globals->deadsz);
125 // Initialize a single context
126 globals->freeContexts = 0;
127 globals->allContexts = 0;
130 globals->symbols = naNewHash(c);
131 globals->save = naNewVector(c);
133 // Cache pre-calculated "me", "arg" and "parents" scalars
134 globals->meRef = naInternSymbol(naStr_fromdata(naNewString(c), "me", 2));
135 globals->argRef = naInternSymbol(naStr_fromdata(naNewString(c), "arg", 3));
136 globals->parentsRef = naInternSymbol(naStr_fromdata(naNewString(c), "parents", 7));
141 struct Context* naNewContext()
149 c = globals->freeContexts;
151 globals->freeContexts = c->nextFree;
157 c = (struct Context*)naAlloc(sizeof(struct Context));
158 // Chicken and egg, can't use naNew because it requires temps to exist
159 c->temps = naObj(T_VEC, (naGC_get(&globals->pools[T_VEC], 1, &dummy))[0]);
162 c->nextAll = globals->allContexts;
164 globals->allContexts = c;
170 void naFreeContext(struct Context* c)
172 naVec_setsize(c->temps, 0);
174 c->nextFree = globals->freeContexts;
175 globals->freeContexts = c;
179 #define PUSH(r) do { \
180 if(ctx->opTop >= MAX_STACK_DEPTH) ERR(ctx, "stack overflow"); \
181 ctx->opStack[ctx->opTop++] = r; \
184 struct Frame* setupFuncall(struct Context* ctx, int nargs, int mcall, int tail)
191 DBG(printf("setupFuncall(nargs:%d, mcall:%d)\n", nargs, mcall);)
193 frame = &ctx->opStack[ctx->opTop - nargs - 1];
194 if(!IS_FUNC(frame[0]))
195 ERR(ctx, "function/method call invoked on uncallable object");
197 // Just do native calls right here, and don't touch the stack
198 // frames; return the current one (unless it's a tail call!).
199 if(frame[0].ref.ptr.func->code.ref.ptr.obj->type == T_CCODE) {
200 naRef obj = mcall ? frame[-1] : naNil();
201 naCFunction fp = frame[0].ref.ptr.func->code.ref.ptr.ccode->fptr;
202 naRef result = (*fp)(ctx, obj, nargs, frame + 1);
203 ctx->opTop -= nargs + 1 + mcall;
205 return &(ctx->fStack[ctx->fTop-1]);
208 if(tail) ctx->fTop--;
209 else if(ctx->fTop >= MAX_RECURSION) ERR(ctx, "call stack overflow");
211 // Note: assign nil first, otherwise the naNew() can cause a GC,
212 // which will now (after fTop++) see the *old* reference as a
214 f = &(ctx->fStack[ctx->fTop++]);
215 f->locals = f->func = naNil();
216 f->locals = naNewHash(ctx);
219 f->bp = ctx->opTop - (nargs + 1 + mcall);
222 naHash_set(f->locals, globals->meRef, frame[-1]);
224 // Set the argument symbols, and put any remaining args in a vector
225 c = (*frame++).ref.ptr.func->code.ref.ptr.code;
226 if(nargs < c->nArgs) ERR(ctx, "not enough arguments to function call");
227 for(i=0; i<c->nArgs; i++)
228 naHash_newsym(f->locals.ref.ptr.hash,
229 &c->constants[c->argSyms[i]], &frame[i]);
232 for(i=0; i<c->nOptArgs; i++, nargs--) {
233 naRef val = nargs > 0 ? frame[i] : c->constants[c->optArgVals[i]];
235 val = bindFunction(ctx, &ctx->fStack[ctx->fTop-2], val);
236 naHash_newsym(f->locals.ref.ptr.hash, &c->constants[c->optArgSyms[i]],
239 if(c->needArgVector || nargs > 0)
241 naRef args = naNewVector(ctx);
242 naVec_setsize(args, nargs > 0 ? nargs : 0);
243 for(i=0; i<nargs; i++)
244 args.ref.ptr.vec->rec->array[i] = *frame++;
245 naHash_newsym(f->locals.ref.ptr.hash, &c->restArgSym, &args);
248 ctx->opTop = f->bp; // Pop the stack last, to avoid GC lossage
249 DBG(printf("Entering frame %d with %d args\n", ctx->fTop-1, nargs);)
253 static naRef evalAndOr(struct Context* ctx, int op, naRef ra, naRef rb)
255 int a = boolify(ctx, ra);
256 int b = boolify(ctx, rb);
258 if(op == OP_AND) result = a && b ? 1 : 0;
259 else result = a || b ? 1 : 0;
260 return naNum(result);
263 static naRef evalEquality(int op, naRef ra, naRef rb)
265 int result = naEqual(ra, rb);
266 return naNum((op==OP_EQ) ? result : !result);
269 // When a code object comes out of the constant pool and shows up on
270 // the stack, it needs to be bound with the lexical context.
271 static naRef bindFunction(struct Context* ctx, struct Frame* f, naRef code)
273 naRef result = naNewFunc(ctx, code);
274 result.ref.ptr.func->namespace = f->locals;
275 result.ref.ptr.func->next = f->func;
279 static int getClosure(struct naFunc* c, naRef sym, naRef* result)
282 if(naHash_get(c->namespace, sym, result)) return 1;
283 c = c->next.ref.ptr.func;
288 static naRef getLocal2(struct Context* ctx, struct Frame* f, naRef sym)
291 if(!naHash_get(f->locals, sym, &result))
292 if(!getClosure(f->func.ref.ptr.func, sym, &result))
293 ERR(ctx, "undefined symbol");
297 static void getLocal(struct Context* ctx, struct Frame* f,
298 naRef* sym, naRef* out)
301 struct naStr* str = sym->ref.ptr.str;
302 if(naHash_sym(f->locals.ref.ptr.hash, str, out))
304 func = f->func.ref.ptr.func;
305 while(func && func->namespace.ref.ptr.hash) {
306 if(naHash_sym(func->namespace.ref.ptr.hash, str, out))
308 func = func->next.ref.ptr.func;
310 // Now do it again using the more general naHash_get(). This will
311 // only be necessary if something has created the value in the
312 // namespace using the more generic hash syntax
313 // (e.g. namespace["symbol"] and not namespace.symbol).
314 *out = getLocal2(ctx, f, *sym);
317 static int setClosure(naRef func, naRef sym, naRef val)
319 struct naFunc* c = func.ref.ptr.func;
320 if(c == 0) { return 0; }
321 else if(naHash_tryset(c->namespace, sym, val)) { return 1; }
322 else { return setClosure(c->next, sym, val); }
325 static naRef setSymbol(struct Frame* f, naRef sym, naRef val)
327 // Try the locals first, if not already there try the closures in
328 // order. Finally put it in the locals if nothing matched.
329 if(!naHash_tryset(f->locals, sym, val))
330 if(!setClosure(f->func, sym, val))
331 naHash_set(f->locals, sym, val);
335 // Recursively descend into the parents lists
336 static int getMember(struct Context* ctx, naRef obj, naRef fld,
337 naRef* result, int count)
340 if(--count < 0) ERR(ctx, "too many parents");
341 if(!IS_HASH(obj)) ERR(ctx, "non-objects have no members");
342 if(naHash_get(obj, fld, result)) {
344 } else if(naHash_get(obj, globals->parentsRef, &p)) {
347 struct VecRec* v = p.ref.ptr.vec->rec;
348 for(i=0; i<v->size; i++)
349 if(getMember(ctx, v->array[i], fld, result, count))
352 ERR(ctx, "parents field not vector");
357 // OP_EACH works like a vector get, except that it leaves the vector
358 // and index on the stack, increments the index after use, and pops
359 // the arguments and pushes a nil if the index is beyond the end.
360 static void evalEach(struct Context* ctx, int useIndex)
362 int idx = (int)(ctx->opStack[ctx->opTop-1].num);
363 naRef vec = ctx->opStack[ctx->opTop-2];
364 if(!IS_VEC(vec)) naRuntimeError(ctx, "foreach enumeration of non-vector");
365 if(!vec.ref.ptr.vec->rec || idx >= vec.ref.ptr.vec->rec->size) {
366 ctx->opTop -= 2; // pop two values
370 ctx->opStack[ctx->opTop-1].num = idx+1; // modify in place
371 PUSH(useIndex ? naNum(idx) : naVec_get(vec, idx));
374 #define ARG() cd->byteCode[f->ip++]
375 #define CONSTARG() cd->constants[ARG()]
376 #define POP() ctx->opStack[--ctx->opTop]
377 #define STK(n) (ctx->opStack[ctx->opTop-(n)])
378 #define FIXFRAME() f = &(ctx->fStack[ctx->fTop-1]); \
379 cd = f->func.ref.ptr.func->code.ref.ptr.code;
380 static naRef run(struct Context* ctx)
390 op = cd->byteCode[f->ip++];
391 DBG(printf("Stack Depth: %d\n", ctx->opTop));
392 DBG(printOpDEBUG(f->ip-1, op));
398 PUSH(ctx->opStack[ctx->opTop-1]);
401 PUSH(ctx->opStack[ctx->opTop-2]);
402 PUSH(ctx->opStack[ctx->opTop-2]);
405 a = STK(1); STK(1) = STK(2); STK(2) = a;
408 #define BINOP(expr) do { \
409 double l = IS_NUM(STK(2)) ? STK(2).num : numify(ctx, STK(2)); \
410 double r = IS_NUM(STK(1)) ? STK(1).num : numify(ctx, STK(1)); \
411 STK(2).ref.reftag = ~NASAL_REFTAG; \
413 ctx->opTop--; } while(0)
415 case OP_PLUS: BINOP(l + r); break;
416 case OP_MINUS: BINOP(l - r); break;
417 case OP_MUL: BINOP(l * r); break;
418 case OP_DIV: BINOP(l / r); break;
419 case OP_LT: BINOP(l < r ? 1 : 0); break;
420 case OP_LTE: BINOP(l <= r ? 1 : 0); break;
421 case OP_GT: BINOP(l > r ? 1 : 0); break;
422 case OP_GTE: BINOP(l >= r ? 1 : 0); break;
426 case OP_EQ: case OP_NEQ:
427 STK(2) = evalEquality(op, STK(2), STK(1));
430 case OP_AND: case OP_OR:
431 STK(2) = evalAndOr(ctx, op, STK(2), STK(1));
435 // stringify can call the GC, so don't take stuff of the stack!
436 a = stringify(ctx, ctx->opStack[ctx->opTop-1]);
437 b = stringify(ctx, ctx->opStack[ctx->opTop-2]);
438 c = naStr_concat(naNewString(ctx), b, a);
443 STK(1) = naNum(-numify(ctx, STK(1)));
446 STK(1) = naNum(boolify(ctx, STK(1)) ? 0 : 1);
450 if(IS_CODE(a)) a = bindFunction(ctx, f, a);
463 PUSH(naNewVector(ctx));
466 naVec_append(STK(2), STK(1));
470 PUSH(naNewHash(ctx));
473 naHash_set(STK(3), STK(2), STK(1));
478 getLocal(ctx, f, &a, &b);
482 STK(2) = setSymbol(f, STK(2), STK(1));
486 naHash_set(f->locals, STK(2), STK(1));
487 STK(2) = STK(1); // FIXME: reverse order of arguments instead!
491 if(!getMember(ctx, STK(1), CONSTARG(), &STK(1), 64))
492 ERR(ctx, "no such member");
495 if(!IS_HASH(STK(3))) ERR(ctx, "non-objects have no members");
496 naHash_set(STK(3), STK(2), STK(1));
497 STK(3) = STK(1); // FIXME: fix arg order instead
501 containerSet(ctx, STK(3), STK(2), STK(1));
502 STK(3) = STK(1); // FIXME: codegen order again...
506 STK(2) = containerGet(ctx, STK(2), STK(1));
510 // Identical to JMP, except for locking
512 f->ip = cd->byteCode[f->ip];
513 DBG(printf(" [Jump to: %d]\n", f->ip);)
516 f->ip = cd->byteCode[f->ip];
517 DBG(printf(" [Jump to: %d]\n", f->ip);)
522 ctx->opTop--; // Pops **ONLY** if it's nil!
524 DBG(printf(" [Jump to: %d]\n", f->ip);)
529 if(!boolify(ctx, POP())) {
531 DBG(printf(" [Jump to: %d]\n", f->ip);)
535 f = setupFuncall(ctx, ARG(), 0, 0);
536 cd = f->func.ref.ptr.func->code.ref.ptr.code;
539 f = setupFuncall(ctx, ARG(), 0, 1);
540 cd = f->func.ref.ptr.func->code.ref.ptr.code;
543 f = setupFuncall(ctx, ARG(), 1, 0);
544 cd = f->func.ref.ptr.func->code.ref.ptr.code;
547 f = setupFuncall(ctx, ARG(), 1, 1);
548 cd = f->func.ref.ptr.func->code.ref.ptr.code;
552 if(--ctx->fTop <= 0) return a;
553 ctx->opTop = f->bp + 1; // restore the correct opstack frame!
563 case OP_MARK: // save stack state (e.g. "setjmp")
564 if(ctx->markTop >= MAX_MARK_DEPTH)
565 naRuntimeError(ctx, "mark stack overflow");
566 ctx->markStack[ctx->markTop++] = ctx->opTop;
568 case OP_UNMARK: // pop stack state set by mark
571 case OP_BREAK: // restore stack state (FOLLOW WITH JMP!)
572 ctx->opTop = ctx->markStack[--ctx->markTop];
575 ERR(ctx, "BUG: bad opcode");
577 ctx->temps.ref.ptr.vec->rec->size = 0; // reset GC temp vector
578 DBG(printStackDEBUG(ctx);)
580 return naNil(); // unreachable
587 void naSave(struct Context* ctx, naRef obj)
589 naVec_append(globals->save, obj);
592 // FIXME: handle ctx->callParent
593 int naStackDepth(struct Context* ctx)
598 // FIXME: handle ctx->callParent
599 int naGetLine(struct Context* ctx, int frame)
601 struct Frame* f = &ctx->fStack[ctx->fTop-1-frame];
602 naRef func = f->func;
604 if(IS_FUNC(func) && IS_CODE(func.ref.ptr.func->code)) {
605 struct naCode* c = func.ref.ptr.func->code.ref.ptr.code;
606 unsigned short* p = c->lineIps + c->nLines - 2;
607 while(p >= c->lineIps && p[0] > ip)
614 // FIXME: handle ctx->callParent
615 naRef naGetSourceFile(struct Context* ctx, int frame)
617 naRef f = ctx->fStack[ctx->fTop-1-frame].func;
618 f = f.ref.ptr.func->code;
619 return f.ref.ptr.code->srcFile;
622 char* naGetError(struct Context* ctx)
624 if(IS_STR(ctx->dieArg))
625 return ctx->dieArg.ref.ptr.str->data;
629 naRef naBindFunction(naContext ctx, naRef code, naRef closure)
631 naRef func = naNewFunc(ctx, code);
632 func.ref.ptr.func->namespace = closure;
633 func.ref.ptr.func->next = naNil();
637 naRef naBindToContext(naContext ctx, naRef code)
639 naRef func = naNewFunc(ctx, code);
640 struct Frame* f = &ctx->fStack[ctx->fTop-1];
641 func.ref.ptr.func->namespace = f->locals;
642 func.ref.ptr.func->next = f->func;
646 naRef naCall(naContext ctx, naRef func, naRef args, naRef obj, naRef locals)
649 if(!ctx->callParent) naModLock(ctx);
651 // We might have to allocate objects, which can call the GC. But
652 // the call isn't on the Nasal stack yet, so the GC won't find our
653 // C-space arguments.
654 naVec_append(ctx->temps, func);
655 naVec_append(ctx->temps, args);
656 naVec_append(ctx->temps, obj);
657 naVec_append(ctx->temps, locals);
660 locals = naNewHash(ctx);
662 func = naNewFunc(ctx, func); // bind bare code objects
665 naHash_set(locals, globals->argRef, args);
667 naHash_set(locals, globals->meRef, obj);
669 ctx->dieArg = naNil();
671 ctx->opTop = ctx->markTop = 0;
673 ctx->fStack[0].func = func;
674 ctx->fStack[0].locals = locals;
675 ctx->fStack[0].ip = 0;
676 ctx->fStack[0].bp = ctx->opTop;
678 // Return early if an error occurred. It will be visible to the
679 // caller via naGetError().
681 if(setjmp(ctx->jumpHandle)) {
682 if(!ctx->callParent) naModUnlock(ctx);
686 if(IS_CCODE(func.ref.ptr.func->code)) {
687 naCFunction fp = func.ref.ptr.func->code.ref.ptr.ccode->fptr;
688 struct naVec* av = args.ref.ptr.vec;
689 result = (*fp)(ctx, obj, av->rec->size, av->rec->array);
692 if(!ctx->callParent) naModUnlock(ctx);