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()
110 globals = (struct Globals*)naAlloc(sizeof(struct Globals));
111 naBZero(globals, sizeof(struct Globals));
113 globals->sem = naNewSem();
114 globals->lock = naNewLock();
117 globals->allocCount = 256; // reasonable starting value
118 for(i=0; i<NUM_NASAL_TYPES; i++)
119 naGC_init(&(globals->pools[i]), i);
120 globals->deadsz = 256;
122 globals->deadBlocks = naAlloc(sizeof(void*) * globals->deadsz);
124 // Initialize a single context
125 globals->freeContexts = 0;
126 globals->allContexts = 0;
127 struct Context* c = naNewContext();
129 globals->symbols = naNewHash(c);
130 globals->save = naNewVector(c);
132 // Cache pre-calculated "me", "arg" and "parents" scalars
133 globals->meRef = naInternSymbol(naStr_fromdata(naNewString(c), "me", 2));
134 globals->argRef = naInternSymbol(naStr_fromdata(naNewString(c), "arg", 3));
135 globals->parentsRef = naInternSymbol(naStr_fromdata(naNewString(c), "parents", 7));
140 struct Context* naNewContext()
147 struct Context* c = globals->freeContexts;
149 globals->freeContexts = c->nextFree;
155 c = (struct Context*)naAlloc(sizeof(struct Context));
156 // Chicken and egg, can't use naNew because it requires temps to exist
157 c->temps = naObj(T_VEC, (naGC_get(&globals->pools[T_VEC], 1, &dummy))[0]);
160 c->nextAll = globals->allContexts;
162 globals->allContexts = c;
168 void naFreeContext(struct Context* c)
170 naVec_setsize(c->temps, 0);
172 c->nextFree = globals->freeContexts;
173 globals->freeContexts = c;
177 #define PUSH(r) do { \
178 if(ctx->opTop >= MAX_STACK_DEPTH) ERR(ctx, "stack overflow"); \
179 ctx->opStack[ctx->opTop++] = r; \
182 struct Frame* setupFuncall(struct Context* ctx, int nargs, int mcall, int tail)
189 DBG(printf("setupFuncall(nargs:%d, mcall:%d)\n", nargs, mcall);)
191 frame = &ctx->opStack[ctx->opTop - nargs - 1];
192 if(!IS_FUNC(frame[0]))
193 ERR(ctx, "function/method call invoked on uncallable object");
195 // Just do native calls right here, and don't touch the stack
196 // frames; return the current one (unless it's a tail call!).
197 if(frame[0].ref.ptr.func->code.ref.ptr.obj->type == T_CCODE) {
198 naRef obj = mcall ? frame[-1] : naNil();
199 naCFunction fp = frame[0].ref.ptr.func->code.ref.ptr.ccode->fptr;
200 naRef result = (*fp)(ctx, obj, nargs, frame + 1);
201 ctx->opTop -= nargs + 1 + mcall;
203 return &(ctx->fStack[ctx->fTop-1]);
206 if(tail) ctx->fTop--;
207 else if(ctx->fTop >= MAX_RECURSION) ERR(ctx, "call stack overflow");
209 // Note: assign nil first, otherwise the naNew() can cause a GC,
210 // which will now (after fTop++) see the *old* reference as a
212 f = &(ctx->fStack[ctx->fTop++]);
213 f->locals = f->func = naNil();
214 f->locals = naNewHash(ctx);
217 f->bp = ctx->opTop - (nargs + 1 + mcall);
220 naHash_set(f->locals, globals->meRef, frame[-1]);
222 // Set the argument symbols, and put any remaining args in a vector
223 c = (*frame++).ref.ptr.func->code.ref.ptr.code;
224 if(nargs < c->nArgs) ERR(ctx, "not enough arguments to function call");
225 for(i=0; i<c->nArgs; i++)
226 naHash_newsym(f->locals.ref.ptr.hash,
227 &c->constants[c->argSyms[i]], &frame[i]);
230 for(i=0; i<c->nOptArgs; i++, nargs--) {
231 naRef val = nargs > 0 ? frame[i] : c->constants[c->optArgVals[i]];
233 val = bindFunction(ctx, &ctx->fStack[ctx->fTop-2], val);
234 naHash_newsym(f->locals.ref.ptr.hash, &c->constants[c->optArgSyms[i]],
237 if(c->needArgVector || nargs > 0)
239 naRef args = naNewVector(ctx);
240 naVec_setsize(args, nargs > 0 ? nargs : 0);
241 for(i=0; i<nargs; i++)
242 args.ref.ptr.vec->rec->array[i] = *frame++;
243 naHash_newsym(f->locals.ref.ptr.hash, &c->restArgSym, &args);
246 ctx->opTop = f->bp; // Pop the stack last, to avoid GC lossage
247 DBG(printf("Entering frame %d with %d args\n", ctx->fTop-1, nargs);)
251 static naRef evalAndOr(struct Context* ctx, int op, naRef ra, naRef rb)
253 int a = boolify(ctx, ra);
254 int b = boolify(ctx, rb);
256 if(op == OP_AND) result = a && b ? 1 : 0;
257 else result = a || b ? 1 : 0;
258 return naNum(result);
261 static naRef evalEquality(int op, naRef ra, naRef rb)
263 int result = naEqual(ra, rb);
264 return naNum((op==OP_EQ) ? result : !result);
267 // When a code object comes out of the constant pool and shows up on
268 // the stack, it needs to be bound with the lexical context.
269 static naRef bindFunction(struct Context* ctx, struct Frame* f, naRef code)
271 naRef result = naNewFunc(ctx, code);
272 result.ref.ptr.func->namespace = f->locals;
273 result.ref.ptr.func->next = f->func;
277 static int getClosure(struct naFunc* c, naRef sym, naRef* result)
280 if(naHash_get(c->namespace, sym, result)) return 1;
281 c = c->next.ref.ptr.func;
286 static naRef getLocal2(struct Context* ctx, struct Frame* f, naRef sym)
289 if(!naHash_get(f->locals, sym, &result))
290 if(!getClosure(f->func.ref.ptr.func, sym, &result))
291 ERR(ctx, "undefined symbol");
295 static void getLocal(struct Context* ctx, struct Frame* f,
296 naRef* sym, naRef* out)
299 struct naStr* str = sym->ref.ptr.str;
300 if(naHash_sym(f->locals.ref.ptr.hash, str, out))
302 func = f->func.ref.ptr.func;
303 while(func && func->namespace.ref.ptr.hash) {
304 if(naHash_sym(func->namespace.ref.ptr.hash, str, out))
306 func = func->next.ref.ptr.func;
308 // Now do it again using the more general naHash_get(). This will
309 // only be necessary if something has created the value in the
310 // namespace using the more generic hash syntax
311 // (e.g. namespace["symbol"] and not namespace.symbol).
312 *out = getLocal2(ctx, f, *sym);
315 static int setClosure(naRef func, naRef sym, naRef val)
317 struct naFunc* c = func.ref.ptr.func;
318 if(c == 0) { return 0; }
319 else if(naHash_tryset(c->namespace, sym, val)) { return 1; }
320 else { return setClosure(c->next, sym, val); }
323 static naRef setSymbol(struct Frame* f, naRef sym, naRef val)
325 // Try the locals first, if not already there try the closures in
326 // order. Finally put it in the locals if nothing matched.
327 if(!naHash_tryset(f->locals, sym, val))
328 if(!setClosure(f->func, sym, val))
329 naHash_set(f->locals, sym, val);
333 // Recursively descend into the parents lists
334 static int getMember(struct Context* ctx, naRef obj, naRef fld,
335 naRef* result, int count)
338 if(--count < 0) ERR(ctx, "too many parents");
339 if(!IS_HASH(obj)) ERR(ctx, "non-objects have no members");
340 if(naHash_get(obj, fld, result)) {
342 } else if(naHash_get(obj, globals->parentsRef, &p)) {
345 struct VecRec* v = p.ref.ptr.vec->rec;
346 for(i=0; i<v->size; i++)
347 if(getMember(ctx, v->array[i], fld, result, count))
350 ERR(ctx, "parents field not vector");
355 // OP_EACH works like a vector get, except that it leaves the vector
356 // and index on the stack, increments the index after use, and pops
357 // the arguments and pushes a nil if the index is beyond the end.
358 static void evalEach(struct Context* ctx)
360 int idx = (int)(ctx->opStack[ctx->opTop-1].num);
361 naRef vec = ctx->opStack[ctx->opTop-2];
362 if(!IS_VEC(vec)) naRuntimeError(ctx, "foreach enumeration of non-vector");
363 if(!vec.ref.ptr.vec->rec || idx >= vec.ref.ptr.vec->rec->size) {
364 ctx->opTop -= 2; // pop two values
368 ctx->opStack[ctx->opTop-1].num = idx+1; // modify in place
369 PUSH(naVec_get(vec, idx));
372 #define ARG() cd->byteCode[f->ip++]
373 #define CONSTARG() cd->constants[ARG()]
374 #define POP() ctx->opStack[--ctx->opTop]
375 #define STK(n) (ctx->opStack[ctx->opTop-(n)])
376 #define FIXFRAME() f = &(ctx->fStack[ctx->fTop-1]); \
377 cd = f->func.ref.ptr.func->code.ref.ptr.code;
378 static naRef run(struct Context* ctx)
388 op = cd->byteCode[f->ip++];
389 DBG(printf("Stack Depth: %d\n", ctx->opTop));
390 DBG(printOpDEBUG(f->ip-1, op));
396 PUSH(ctx->opStack[ctx->opTop-1]);
399 a = STK(1); STK(1) = STK(2); STK(2) = a;
402 #define BINOP(expr) do { \
403 double l = IS_NUM(STK(2)) ? STK(2).num : numify(ctx, STK(2)); \
404 double r = IS_NUM(STK(1)) ? STK(1).num : numify(ctx, STK(1)); \
405 STK(2).ref.reftag = ~NASAL_REFTAG; \
407 ctx->opTop--; } while(0)
409 case OP_PLUS: BINOP(l + r); break;
410 case OP_MINUS: BINOP(l - r); break;
411 case OP_MUL: BINOP(l * r); break;
412 case OP_DIV: BINOP(l / r); break;
413 case OP_LT: BINOP(l < r ? 1 : 0); break;
414 case OP_LTE: BINOP(l <= r ? 1 : 0); break;
415 case OP_GT: BINOP(l > r ? 1 : 0); break;
416 case OP_GTE: BINOP(l >= r ? 1 : 0); break;
420 case OP_EQ: case OP_NEQ:
421 STK(2) = evalEquality(op, STK(2), STK(1));
424 case OP_AND: case OP_OR:
425 STK(2) = evalAndOr(ctx, op, STK(2), STK(1));
429 // stringify can call the GC, so don't take stuff of the stack!
430 a = stringify(ctx, ctx->opStack[ctx->opTop-1]);
431 b = stringify(ctx, ctx->opStack[ctx->opTop-2]);
432 c = naStr_concat(naNewString(ctx), b, a);
437 STK(1) = naNum(-numify(ctx, STK(1)));
440 STK(1) = naNum(boolify(ctx, STK(1)) ? 0 : 1);
444 if(IS_CODE(a)) a = bindFunction(ctx, f, a);
457 PUSH(naNewVector(ctx));
460 naVec_append(STK(2), STK(1));
464 PUSH(naNewHash(ctx));
467 naHash_set(STK(3), STK(2), STK(1));
472 getLocal(ctx, f, &a, &b);
476 STK(2) = setSymbol(f, STK(2), STK(1));
480 naHash_set(f->locals, STK(2), STK(1));
481 STK(2) = STK(1); // FIXME: reverse order of arguments instead!
485 if(!getMember(ctx, STK(1), CONSTARG(), &STK(1), 64))
486 ERR(ctx, "no such member");
489 if(!IS_HASH(STK(3))) ERR(ctx, "non-objects have no members");
490 naHash_set(STK(3), STK(2), STK(1));
491 STK(3) = STK(1); // FIXME: fix arg order instead
495 containerSet(ctx, STK(3), STK(2), STK(1));
496 STK(3) = STK(1); // FIXME: codegen order again...
500 STK(2) = containerGet(ctx, STK(2), STK(1));
504 // Identical to JMP, except for locking
506 f->ip = cd->byteCode[f->ip];
507 DBG(printf(" [Jump to: %d]\n", f->ip);)
510 f->ip = cd->byteCode[f->ip];
511 DBG(printf(" [Jump to: %d]\n", f->ip);)
516 ctx->opTop--; // Pops **ONLY** if it's nil!
518 DBG(printf(" [Jump to: %d]\n", f->ip);)
523 if(!boolify(ctx, POP())) {
525 DBG(printf(" [Jump to: %d]\n", f->ip);)
529 f = setupFuncall(ctx, ARG(), 0, 0);
530 cd = f->func.ref.ptr.func->code.ref.ptr.code;
533 f = setupFuncall(ctx, ARG(), 0, 1);
534 cd = f->func.ref.ptr.func->code.ref.ptr.code;
537 f = setupFuncall(ctx, ARG(), 1, 0);
538 cd = f->func.ref.ptr.func->code.ref.ptr.code;
541 f = setupFuncall(ctx, ARG(), 1, 1);
542 cd = f->func.ref.ptr.func->code.ref.ptr.code;
546 if(--ctx->fTop <= 0) return a;
547 ctx->opTop = f->bp + 1; // restore the correct opstack frame!
554 case OP_MARK: // save stack state (e.g. "setjmp")
555 if(ctx->markTop >= MAX_MARK_DEPTH)
556 naRuntimeError(ctx, "mark stack overflow");
557 ctx->markStack[ctx->markTop++] = ctx->opTop;
559 case OP_UNMARK: // pop stack state set by mark
562 case OP_BREAK: // restore stack state (FOLLOW WITH JMP!)
563 ctx->opTop = ctx->markStack[--ctx->markTop];
566 ERR(ctx, "BUG: bad opcode");
568 ctx->temps.ref.ptr.vec->rec->size = 0; // reset GC temp vector
569 DBG(printStackDEBUG(ctx);)
571 return naNil(); // unreachable
578 void naSave(struct Context* ctx, naRef obj)
580 naVec_append(globals->save, obj);
583 // FIXME: handle ctx->callParent
584 int naStackDepth(struct Context* ctx)
589 // FIXME: handle ctx->callParent
590 int naGetLine(struct Context* ctx, int frame)
592 struct Frame* f = &ctx->fStack[ctx->fTop-1-frame];
593 naRef func = f->func;
595 if(IS_FUNC(func) && IS_CODE(func.ref.ptr.func->code)) {
596 struct naCode* c = func.ref.ptr.func->code.ref.ptr.code;
597 unsigned short* p = c->lineIps + c->nLines - 2;
598 while(p >= c->lineIps && p[0] > ip)
605 // FIXME: handle ctx->callParent
606 naRef naGetSourceFile(struct Context* ctx, int frame)
608 naRef f = ctx->fStack[ctx->fTop-1-frame].func;
609 f = f.ref.ptr.func->code;
610 return f.ref.ptr.code->srcFile;
613 char* naGetError(struct Context* ctx)
615 if(IS_STR(ctx->dieArg))
616 return ctx->dieArg.ref.ptr.str->data;
620 naRef naBindFunction(naContext ctx, naRef code, naRef closure)
622 naRef func = naNewFunc(ctx, code);
623 func.ref.ptr.func->namespace = closure;
624 func.ref.ptr.func->next = naNil();
628 naRef naBindToContext(naContext ctx, naRef code)
630 naRef func = naNewFunc(ctx, code);
631 struct Frame* f = &ctx->fStack[ctx->fTop-1];
632 func.ref.ptr.func->namespace = f->locals;
633 func.ref.ptr.func->next = f->func;
637 naRef naCall(naContext ctx, naRef func, naRef args, naRef obj, naRef locals)
640 if(!ctx->callParent) naModLock(ctx);
642 // We might have to allocate objects, which can call the GC. But
643 // the call isn't on the Nasal stack yet, so the GC won't find our
644 // C-space arguments.
645 naVec_append(ctx->temps, func);
646 naVec_append(ctx->temps, args);
647 naVec_append(ctx->temps, obj);
648 naVec_append(ctx->temps, locals);
651 locals = naNewHash(ctx);
653 func = naNewFunc(ctx, func); // bind bare code objects
656 naHash_set(locals, globals->argRef, args);
658 naHash_set(locals, globals->meRef, obj);
660 ctx->dieArg = naNil();
662 ctx->opTop = ctx->markTop = 0;
664 ctx->fStack[0].func = func;
665 ctx->fStack[0].locals = locals;
666 ctx->fStack[0].ip = 0;
667 ctx->fStack[0].bp = ctx->opTop;
669 // Return early if an error occurred. It will be visible to the
670 // caller via naGetError().
672 if(setjmp(ctx->jumpHandle))
675 if(IS_CCODE(func.ref.ptr.func->code)) {
676 naCFunction fp = func.ref.ptr.func->code.ref.ptr.ccode->fptr;
677 struct naVec* av = args.ref.ptr.vec;
678 result = (*fp)(ctx, obj, av->rec->size, av->rec->array);
681 if(!ctx->callParent) naModUnlock(ctx);