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 += naVec_size(vec);
68 if(i < 0 || i >= naVec_size(vec)) ERR(ctx, "vector index out of bounds");
72 static int checkStr(struct Context* ctx, naRef str, naRef idx)
74 int i = (int)numify(ctx, idx);
75 if(i < 0) i += naStr_len(str);
76 if(i < 0 || i >= naStr_len(str)) ERR(ctx, "string index out of bounds");
80 static naRef containerGet(struct Context* ctx, naRef box, naRef key)
82 naRef result = naNil();
83 if(!IS_SCALAR(key)) ERR(ctx, "container index not scalar");
85 if(!naHash_get(box, key, &result))
86 ERR(ctx, "undefined value in container");
87 } else if(IS_VEC(box)) {
88 result = naVec_get(box, checkVec(ctx, box, key));
89 } else if(IS_STR(box)) {
90 result = naNum((unsigned char)naStr_data(box)[checkStr(ctx, box, key)]);
92 ERR(ctx, "extract from non-container");
97 static void containerSet(struct Context* ctx, naRef box, naRef key, naRef val)
99 if(!IS_SCALAR(key)) ERR(ctx, "container index not scalar");
100 else if(IS_HASH(box)) naHash_set(box, key, val);
101 else if(IS_VEC(box)) naVec_set(box, checkVec(ctx, box, key), val);
102 else if(IS_STR(box)) {
103 if(box.ref.ptr.str->hashcode)
104 ERR(ctx, "cannot change immutable string");
105 naStr_data(box)[checkStr(ctx, box, key)] = (char)numify(ctx, val);
106 } else ERR(ctx, "insert into non-container");
109 static void initTemps(struct Context* c)
112 c->temps = naAlloc(c->tempsz * sizeof(struct naObj*));
116 static void initContext(struct Context* c)
119 c->fTop = c->opTop = c->markTop = 0;
120 for(i=0; i<NUM_NASAL_TYPES; i++)
134 static void initGlobals()
138 globals = (struct Globals*)naAlloc(sizeof(struct Globals));
139 naBZero(globals, sizeof(struct Globals));
141 globals->sem = naNewSem();
142 globals->lock = naNewLock();
144 globals->allocCount = 256; // reasonable starting value
145 for(i=0; i<NUM_NASAL_TYPES; i++)
146 naGC_init(&(globals->pools[i]), i);
147 globals->deadsz = 256;
149 globals->deadBlocks = naAlloc(sizeof(void*) * globals->deadsz);
151 // Initialize a single context
152 globals->freeContexts = 0;
153 globals->allContexts = 0;
156 globals->symbols = naNewHash(c);
157 globals->save = naNewVector(c);
159 // Cache pre-calculated "me", "arg" and "parents" scalars
160 globals->meRef = naInternSymbol(naStr_fromdata(naNewString(c), "me", 2));
161 globals->argRef = naInternSymbol(naStr_fromdata(naNewString(c), "arg", 3));
162 globals->parentsRef = naInternSymbol(naStr_fromdata(naNewString(c), "parents", 7));
167 struct Context* naNewContext()
174 c = globals->freeContexts;
176 globals->freeContexts = c->nextFree;
182 c = (struct Context*)naAlloc(sizeof(struct Context));
186 c->nextAll = globals->allContexts;
188 globals->allContexts = c;
194 void naFreeContext(struct Context* c)
198 c->nextFree = globals->freeContexts;
199 globals->freeContexts = c;
203 #define PUSH(r) do { \
204 if(ctx->opTop >= MAX_STACK_DEPTH) ERR(ctx, "stack overflow"); \
205 ctx->opStack[ctx->opTop++] = r; \
208 static void setupArgs(naContext ctx, struct Frame* f, naRef* args, int nargs)
211 struct naCode* c = f->func.ref.ptr.func->code.ref.ptr.code;
213 // Set the argument symbols, and put any remaining args in a vector
214 if(nargs < c->nArgs) ERR(ctx, "not enough arguments to function call");
215 for(i=0; i<c->nArgs; i++)
216 naHash_newsym(f->locals.ref.ptr.hash,
217 &c->constants[c->argSyms[i]], &args[i]);
220 for(i=0; i<c->nOptArgs; i++, nargs--) {
221 naRef val = nargs > 0 ? args[i] : c->constants[c->optArgVals[i]];
223 val = bindFunction(ctx, &ctx->fStack[ctx->fTop-2], val);
224 naHash_newsym(f->locals.ref.ptr.hash, &c->constants[c->optArgSyms[i]],
228 if(c->needArgVector || nargs > 0) {
229 naRef argsv = naNewVector(ctx);
230 naVec_setsize(argsv, nargs > 0 ? nargs : 0);
231 for(i=0; i<nargs; i++)
232 argsv.ref.ptr.vec->rec->array[i] = *args++;
233 naHash_newsym(f->locals.ref.ptr.hash, &c->restArgSym, &argsv);
237 struct Frame* setupFuncall(struct Context* ctx, int nargs, int mcall, int tail)
242 DBG(printf("setupFuncall(nargs:%d, mcall:%d)\n", nargs, mcall);)
244 frame = &ctx->opStack[ctx->opTop - nargs - 1];
245 if(!IS_FUNC(frame[0]))
246 ERR(ctx, "function/method call invoked on uncallable object");
248 // Just do native calls right here, and don't touch the stack
249 // frames; return the current one (unless it's a tail call!).
250 if(frame[0].ref.ptr.func->code.ref.ptr.obj->type == T_CCODE) {
251 naRef obj = mcall ? frame[-1] : naNil();
252 naCFunction fp = frame[0].ref.ptr.func->code.ref.ptr.ccode->fptr;
253 naRef result = (*fp)(ctx, obj, nargs, frame + 1);
254 ctx->opTop -= nargs + 1 + mcall;
256 return &(ctx->fStack[ctx->fTop-1]);
259 if(tail) ctx->fTop--;
260 else if(ctx->fTop >= MAX_RECURSION) ERR(ctx, "call stack overflow");
262 // Note: assign nil first, otherwise the naNew() can cause a GC,
263 // which will now (after fTop++) see the *old* reference as a
265 f = &(ctx->fStack[ctx->fTop++]);
266 f->locals = f->func = naNil();
267 f->locals = naNewHash(ctx);
270 f->bp = ctx->opTop - (nargs + 1 + mcall);
273 naHash_set(f->locals, globals->meRef, frame[-1]);
275 setupArgs(ctx, f, frame+1, nargs);
277 ctx->opTop = f->bp; // Pop the stack last, to avoid GC lossage
278 DBG(printf("Entering frame %d with %d args\n", ctx->fTop-1, nargs);)
282 static naRef evalAndOr(struct Context* ctx, int op, naRef ra, naRef rb)
284 int a = boolify(ctx, ra);
285 int b = boolify(ctx, rb);
287 if(op == OP_AND) result = a && b ? 1 : 0;
288 else result = a || b ? 1 : 0;
289 return naNum(result);
292 static naRef evalEquality(int op, naRef ra, naRef rb)
294 int result = naEqual(ra, rb);
295 return naNum((op==OP_EQ) ? result : !result);
298 // When a code object comes out of the constant pool and shows up on
299 // the stack, it needs to be bound with the lexical context.
300 static naRef bindFunction(struct Context* ctx, struct Frame* f, naRef code)
302 naRef result = naNewFunc(ctx, code);
303 result.ref.ptr.func->namespace = f->locals;
304 result.ref.ptr.func->next = f->func;
308 static int getClosure(struct naFunc* c, naRef sym, naRef* result)
311 if(naHash_get(c->namespace, sym, result)) return 1;
312 c = c->next.ref.ptr.func;
317 static naRef getLocal2(struct Context* ctx, struct Frame* f, naRef sym)
320 if(!naHash_get(f->locals, sym, &result))
321 if(!getClosure(f->func.ref.ptr.func, sym, &result))
322 ERR(ctx, "undefined symbol");
326 static void getLocal(struct Context* ctx, struct Frame* f,
327 naRef* sym, naRef* out)
330 struct naStr* str = sym->ref.ptr.str;
331 if(naHash_sym(f->locals.ref.ptr.hash, str, out))
333 func = f->func.ref.ptr.func;
334 while(func && func->namespace.ref.ptr.hash) {
335 if(naHash_sym(func->namespace.ref.ptr.hash, str, out))
337 func = func->next.ref.ptr.func;
339 // Now do it again using the more general naHash_get(). This will
340 // only be necessary if something has created the value in the
341 // namespace using the more generic hash syntax
342 // (e.g. namespace["symbol"] and not namespace.symbol).
343 *out = getLocal2(ctx, f, *sym);
346 static int setClosure(naRef func, naRef sym, naRef val)
348 struct naFunc* c = func.ref.ptr.func;
349 if(c == 0) { return 0; }
350 else if(naHash_tryset(c->namespace, sym, val)) { return 1; }
351 else { return setClosure(c->next, sym, val); }
354 static naRef setSymbol(struct Frame* f, naRef sym, naRef val)
356 // Try the locals first, if not already there try the closures in
357 // order. Finally put it in the locals if nothing matched.
358 if(!naHash_tryset(f->locals, sym, val))
359 if(!setClosure(f->func, sym, val))
360 naHash_set(f->locals, sym, val);
364 // Recursively descend into the parents lists
365 static int getMember(struct Context* ctx, naRef obj, naRef fld,
366 naRef* result, int count)
369 if(--count < 0) ERR(ctx, "too many parents");
370 if(!IS_HASH(obj)) ERR(ctx, "non-objects have no members");
371 if(naHash_get(obj, fld, result)) {
373 } else if(naHash_get(obj, globals->parentsRef, &p)) {
376 struct VecRec* v = p.ref.ptr.vec->rec;
377 for(i=0; i<v->size; i++)
378 if(getMember(ctx, v->array[i], fld, result, count))
381 ERR(ctx, "parents field not vector");
386 // OP_EACH works like a vector get, except that it leaves the vector
387 // and index on the stack, increments the index after use, and pops
388 // the arguments and pushes a nil if the index is beyond the end.
389 static void evalEach(struct Context* ctx, int useIndex)
391 int idx = (int)(ctx->opStack[ctx->opTop-1].num);
392 naRef vec = ctx->opStack[ctx->opTop-2];
393 if(!IS_VEC(vec)) naRuntimeError(ctx, "foreach enumeration of non-vector");
394 if(!vec.ref.ptr.vec->rec || idx >= vec.ref.ptr.vec->rec->size) {
395 ctx->opTop -= 2; // pop two values
399 ctx->opStack[ctx->opTop-1].num = idx+1; // modify in place
400 PUSH(useIndex ? naNum(idx) : naVec_get(vec, idx));
403 #define ARG() cd->byteCode[f->ip++]
404 #define CONSTARG() cd->constants[ARG()]
405 #define POP() ctx->opStack[--ctx->opTop]
406 #define STK(n) (ctx->opStack[ctx->opTop-(n)])
407 #define FIXFRAME() f = &(ctx->fStack[ctx->fTop-1]); \
408 cd = f->func.ref.ptr.func->code.ref.ptr.code;
409 static naRef run(struct Context* ctx)
419 op = cd->byteCode[f->ip++];
420 DBG(printf("Stack Depth: %d\n", ctx->opTop));
421 DBG(printOpDEBUG(f->ip-1, op));
427 PUSH(ctx->opStack[ctx->opTop-1]);
430 PUSH(ctx->opStack[ctx->opTop-2]);
431 PUSH(ctx->opStack[ctx->opTop-2]);
434 a = STK(1); STK(1) = STK(2); STK(2) = a;
437 #define BINOP(expr) do { \
438 double l = IS_NUM(STK(2)) ? STK(2).num : numify(ctx, STK(2)); \
439 double r = IS_NUM(STK(1)) ? STK(1).num : numify(ctx, STK(1)); \
440 STK(2).ref.reftag = ~NASAL_REFTAG; \
442 ctx->opTop--; } while(0)
444 case OP_PLUS: BINOP(l + r); break;
445 case OP_MINUS: BINOP(l - r); break;
446 case OP_MUL: BINOP(l * r); break;
447 case OP_DIV: BINOP(l / r); break;
448 case OP_LT: BINOP(l < r ? 1 : 0); break;
449 case OP_LTE: BINOP(l <= r ? 1 : 0); break;
450 case OP_GT: BINOP(l > r ? 1 : 0); break;
451 case OP_GTE: BINOP(l >= r ? 1 : 0); break;
455 case OP_EQ: case OP_NEQ:
456 STK(2) = evalEquality(op, STK(2), STK(1));
459 case OP_AND: case OP_OR:
460 STK(2) = evalAndOr(ctx, op, STK(2), STK(1));
464 // stringify can call the GC, so don't take stuff of the stack!
465 a = stringify(ctx, ctx->opStack[ctx->opTop-1]);
466 b = stringify(ctx, ctx->opStack[ctx->opTop-2]);
467 c = naStr_concat(naNewString(ctx), b, a);
472 STK(1) = naNum(-numify(ctx, STK(1)));
475 STK(1) = naNum(boolify(ctx, STK(1)) ? 0 : 1);
479 if(IS_CODE(a)) a = bindFunction(ctx, f, a);
492 PUSH(naNewVector(ctx));
495 naVec_append(STK(2), STK(1));
499 PUSH(naNewHash(ctx));
502 naHash_set(STK(3), STK(2), STK(1));
507 getLocal(ctx, f, &a, &b);
511 STK(2) = setSymbol(f, STK(2), STK(1));
515 naHash_set(f->locals, STK(2), STK(1));
516 STK(2) = STK(1); // FIXME: reverse order of arguments instead!
520 if(!getMember(ctx, STK(1), CONSTARG(), &STK(1), 64))
521 ERR(ctx, "no such member");
524 if(!IS_HASH(STK(3))) ERR(ctx, "non-objects have no members");
525 naHash_set(STK(3), STK(2), STK(1));
526 STK(3) = STK(1); // FIXME: fix arg order instead
530 containerSet(ctx, STK(3), STK(2), STK(1));
531 STK(3) = STK(1); // FIXME: codegen order again...
535 STK(2) = containerGet(ctx, STK(2), STK(1));
539 // Identical to JMP, except for locking
541 f->ip = cd->byteCode[f->ip];
542 DBG(printf(" [Jump to: %d]\n", f->ip);)
545 f->ip = cd->byteCode[f->ip];
546 DBG(printf(" [Jump to: %d]\n", f->ip);)
551 ctx->opTop--; // Pops **ONLY** if it's nil!
553 DBG(printf(" [Jump to: %d]\n", f->ip);)
558 if(!boolify(ctx, POP())) {
560 DBG(printf(" [Jump to: %d]\n", f->ip);)
564 f = setupFuncall(ctx, ARG(), 0, 0);
565 cd = f->func.ref.ptr.func->code.ref.ptr.code;
568 f = setupFuncall(ctx, ARG(), 0, 1);
569 cd = f->func.ref.ptr.func->code.ref.ptr.code;
572 f = setupFuncall(ctx, ARG(), 1, 0);
573 cd = f->func.ref.ptr.func->code.ref.ptr.code;
576 f = setupFuncall(ctx, ARG(), 1, 1);
577 cd = f->func.ref.ptr.func->code.ref.ptr.code;
581 if(--ctx->fTop <= 0) return a;
582 ctx->opTop = f->bp + 1; // restore the correct opstack frame!
592 case OP_MARK: // save stack state (e.g. "setjmp")
593 if(ctx->markTop >= MAX_MARK_DEPTH)
594 naRuntimeError(ctx, "mark stack overflow");
595 ctx->markStack[ctx->markTop++] = ctx->opTop;
597 case OP_UNMARK: // pop stack state set by mark
600 case OP_BREAK: // restore stack state (FOLLOW WITH JMP!)
601 ctx->opTop = ctx->markStack[--ctx->markTop];
604 ERR(ctx, "BUG: bad opcode");
606 ctx->ntemps = 0; // reset GC temp vector
607 DBG(printStackDEBUG(ctx);)
609 return naNil(); // unreachable
616 void naSave(struct Context* ctx, naRef obj)
618 naVec_append(globals->save, obj);
621 // FIXME: handle ctx->callParent
622 int naStackDepth(struct Context* ctx)
627 // FIXME: handle ctx->callParent
628 int naGetLine(struct Context* ctx, int frame)
630 struct Frame* f = &ctx->fStack[ctx->fTop-1-frame];
631 naRef func = f->func;
633 if(IS_FUNC(func) && IS_CODE(func.ref.ptr.func->code)) {
634 struct naCode* c = func.ref.ptr.func->code.ref.ptr.code;
635 unsigned short* p = c->lineIps + c->nLines - 2;
636 while(p >= c->lineIps && p[0] > ip)
643 // FIXME: handle ctx->callParent
644 naRef naGetSourceFile(struct Context* ctx, int frame)
646 naRef f = ctx->fStack[ctx->fTop-1-frame].func;
647 f = f.ref.ptr.func->code;
648 return f.ref.ptr.code->srcFile;
651 char* naGetError(struct Context* ctx)
653 if(IS_STR(ctx->dieArg))
654 return (char*)ctx->dieArg.ref.ptr.str->data;
658 naRef naBindFunction(naContext ctx, naRef code, naRef closure)
660 naRef func = naNewFunc(ctx, code);
661 func.ref.ptr.func->namespace = closure;
662 func.ref.ptr.func->next = naNil();
666 naRef naBindToContext(naContext ctx, naRef code)
668 naRef func = naNewFunc(ctx, code);
669 struct Frame* f = &ctx->fStack[ctx->fTop-1];
670 func.ref.ptr.func->namespace = f->locals;
671 func.ref.ptr.func->next = f->func;
675 naRef naCall(naContext ctx, naRef func, int argc, naRef* args,
676 naRef obj, naRef locals)
680 if(!ctx->callParent) naModLock(ctx);
682 // We might have to allocate objects, which can call the GC. But
683 // the call isn't on the Nasal stack yet, so the GC won't find our
684 // C-space arguments.
685 naTempSave(ctx, func);
686 for(i=0; i<argc; i++)
687 naTempSave(ctx, args[i]);
688 naTempSave(ctx, obj);
689 naTempSave(ctx, locals);
691 if(IS_CCODE(func.ref.ptr.func->code)) {
692 naCFunction fp = func.ref.ptr.func->code.ref.ptr.ccode->fptr;
693 result = (*fp)(ctx, obj, argc, args);
694 if(!ctx->callParent) naModUnlock(ctx);
699 locals = naNewHash(ctx);
701 func = naNewFunc(ctx, func); // bind bare code objects
703 naHash_set(locals, globals->meRef, obj);
705 ctx->dieArg = naNil();
707 ctx->opTop = ctx->markTop = 0;
709 ctx->fStack[0].func = func;
710 ctx->fStack[0].locals = locals;
711 ctx->fStack[0].ip = 0;
712 ctx->fStack[0].bp = ctx->opTop;
714 setupArgs(ctx, ctx->fStack, args, argc);
716 // Return early if an error occurred. It will be visible to the
717 // caller via naGetError().
719 if(setjmp(ctx->jumpHandle)) {
720 if(!ctx->callParent) naModUnlock(ctx);
725 if(!ctx->callParent) naModUnlock(ctx);