1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2 *
3 * ***** BEGIN LICENSE BLOCK *****
4 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
5 *
6 * The contents of this file are subject to the Mozilla Public License Version
7 * 1.1 (the "License"); you may not use this file except in compliance with
8 * the License. You may obtain a copy of the License at
9 * http://www.mozilla.org/MPL/
10 *
11 * Software distributed under the License is distributed on an "AS IS" basis,
12 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13 * for the specific language governing rights and limitations under the
14 * License.
15 *
16 * The Original Code is Mozilla Communicator client code, released
17 * March 31, 1998.
18 *
19 * The Initial Developer of the Original Code is
20 * Netscape Communications Corporation.
21 * Portions created by the Initial Developer are Copyright (C) 1998
22 * the Initial Developer. All Rights Reserved.
23 *
24 * Contributor(s):
25 *
26 * Alternatively, the contents of this file may be used under the terms of
27 * either of the GNU General Public License Version 2 or later (the "GPL"),
28 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29 * in which case the provisions of the GPL or the LGPL are applicable instead
30 * of those above. If you wish to allow use of your version of this file only
31 * under the terms of either the GPL or the LGPL, and not to allow others to
32 * use your version of this file under the terms of the MPL, indicate your
33 * decision by deleting the provisions above and replace them with the notice
34 * and other provisions required by the GPL or the LGPL. If you do not delete
35 * the provisions above, a recipient may use your version of this file under
36 * the terms of any one of the MPL, the GPL or the LGPL.
37 *
38 * ***** END LICENSE BLOCK ***** */
40 /*
41 * JS script operations.
42 */
43 #include "jsstddef.h"
44 #include <string.h>
45 #include "jstypes.h"
46 #include "jsutil.h" /* Added by JSIFY */
47 #include "jsprf.h"
48 #include "jsapi.h"
49 #include "jsatom.h"
50 #include "jscntxt.h"
51 #include "jsconfig.h"
52 #include "jsdbgapi.h"
53 #include "jsemit.h"
54 #include "jsfun.h"
55 #include "jsinterp.h"
56 #include "jslock.h"
57 #include "jsnum.h"
58 #include "jsopcode.h"
59 #include "jsscript.h"
60 #if JS_HAS_XDR
61 #include "jsxdrapi.h"
62 #endif
64 #if JS_HAS_SCRIPT_OBJECT
66 #if JS_HAS_TOSOURCE
67 static JSBool
68 script_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
69 jsval *rval)
70 {
71 JSScript *script;
72 size_t i, j, k, n;
73 char buf[16];
74 jschar *s, *t;
75 uint32 indent;
76 JSString *str;
78 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
79 return JS_FALSE;
80 script = (JSScript *) JS_GetPrivate(cx, obj);
82 /* Let n count the source string length, j the "front porch" length. */
83 j = JS_snprintf(buf, sizeof buf, "(new %s(", js_ScriptClass.name);
84 n = j + 2;
85 if (!script) {
86 /* Let k count the constructor argument string length. */
87 k = 0;
88 s = NULL; /* quell GCC overwarning */
89 } else {
90 indent = 0;
91 if (argc && !js_ValueToECMAUint32(cx, argv[0], &indent))
92 return JS_FALSE;
93 str = JS_DecompileScript(cx, script, "Script.prototype.toSource",
94 (uintN)indent);
95 if (!str)
96 return JS_FALSE;
97 str = js_QuoteString(cx, str, '\'');
98 if (!str)
99 return JS_FALSE;
100 s = JSSTRING_CHARS(str);
101 k = JSSTRING_LENGTH(str);
102 n += k;
103 }
105 /* Allocate the source string and copy into it. */
106 t = (jschar *) JS_malloc(cx, (n + 1) * sizeof(jschar));
107 if (!t)
108 return JS_FALSE;
109 for (i = 0; i < j; i++)
110 t[i] = buf[i];
111 for (j = 0; j < k; i++, j++)
112 t[i] = s[j];
113 t[i++] = ')';
114 t[i++] = ')';
115 t[i] = 0;
117 /* Create and return a JS string for t. */
118 str = JS_NewUCString(cx, t, n);
119 if (!str) {
120 JS_free(cx, t);
121 return JS_FALSE;
122 }
123 *rval = STRING_TO_JSVAL(str);
124 return JS_TRUE;
125 }
126 #endif /* JS_HAS_TOSOURCE */
128 static JSBool
129 script_toString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
130 jsval *rval)
131 {
132 JSScript *script;
133 uint32 indent;
134 JSString *str;
136 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
137 return JS_FALSE;
138 script = (JSScript *) JS_GetPrivate(cx, obj);
139 if (!script) {
140 *rval = STRING_TO_JSVAL(cx->runtime->emptyString);
141 return JS_TRUE;
142 }
144 indent = 0;
145 if (argc && !js_ValueToECMAUint32(cx, argv[0], &indent))
146 return JS_FALSE;
147 str = JS_DecompileScript(cx, script, "Script.prototype.toString",
148 (uintN)indent);
149 if (!str)
150 return JS_FALSE;
151 *rval = STRING_TO_JSVAL(str);
152 return JS_TRUE;
153 }
155 static JSBool
156 script_compile(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
157 jsval *rval)
158 {
159 JSScript *oldscript, *script;
160 JSString *str;
161 JSStackFrame *fp, *caller;
162 JSObject *scopeobj;
163 const char *file;
164 uintN line;
165 JSPrincipals *principals;
167 /* Make sure obj is a Script object. */
168 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
169 return JS_FALSE;
171 /* If no args, leave private undefined and return early. */
172 if (argc == 0)
173 goto out;
175 /* Otherwise, the first arg is the script source to compile. */
176 str = js_ValueToString(cx, argv[0]);
177 if (!str)
178 return JS_FALSE;
180 /* Compile using the caller's scope chain, which js_Invoke passes to fp. */
181 fp = cx->fp;
182 caller = JS_GetScriptedCaller(cx, fp);
183 JS_ASSERT(!caller || fp->scopeChain == caller->scopeChain);
185 scopeobj = NULL;
186 if (argc >= 2) {
187 if (!js_ValueToObject(cx, argv[1], &scopeobj))
188 return JS_FALSE;
189 argv[1] = OBJECT_TO_JSVAL(scopeobj);
190 }
191 if (caller) {
192 if (!scopeobj)
193 scopeobj = caller->scopeChain;
195 file = caller->script->filename;
196 line = js_PCToLineNumber(cx, caller->script, caller->pc);
197 principals = JS_EvalFramePrincipals(cx, fp, caller);
198 } else {
199 file = NULL;
200 line = 0;
201 principals = NULL;
202 }
204 /* XXXbe set only for the compiler, which does not currently test it */
205 fp->flags |= JSFRAME_EVAL;
207 /* Compile the new script using the caller's scope chain, a la eval(). */
208 script = JS_CompileUCScriptForPrincipals(cx, scopeobj, principals,
209 JSSTRING_CHARS(str),
210 JSSTRING_LENGTH(str),
211 file, line);
212 if (!script)
213 return JS_FALSE;
215 /* Swap script for obj's old script, if any. */
216 oldscript = (JSScript *) JS_GetPrivate(cx, obj);
217 if (!JS_SetPrivate(cx, obj, script)) {
218 js_DestroyScript(cx, script);
219 return JS_FALSE;
220 }
221 if (oldscript)
222 js_DestroyScript(cx, oldscript);
224 script->object = obj;
225 out:
226 /* Return the object. */
227 *rval = OBJECT_TO_JSVAL(obj);
228 return JS_TRUE;
229 }
231 static JSBool
232 script_exec(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
233 {
234 JSScript *script;
235 JSObject *scopeobj, *parent;
236 JSStackFrame *fp, *caller;
238 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
239 return JS_FALSE;
240 script = (JSScript *) JS_GetPrivate(cx, obj);
241 if (!script)
242 return JS_TRUE;
244 scopeobj = NULL;
245 if (argc) {
246 if (!js_ValueToObject(cx, argv[0], &scopeobj))
247 return JS_FALSE;
248 argv[0] = OBJECT_TO_JSVAL(scopeobj);
249 }
251 /*
252 * Emulate eval() by using caller's this, var object, sharp array, etc.,
253 * all propagated by js_Execute via a non-null fourth (down) argument to
254 * js_Execute. If there is no scripted caller, js_Execute uses its second
255 * (chain) argument to set the exec frame's varobj, thisp, and scopeChain.
256 *
257 * Unlike eval, which the compiler detects, Script.prototype.exec may be
258 * called from a lightweight function, or even from native code (in which
259 * case fp->varobj and fp->scopeChain are null). If exec is called from
260 * a lightweight function, we will need to get a Call object representing
261 * its frame, to act as the var object and scope chain head.
262 */
263 fp = cx->fp;
264 caller = JS_GetScriptedCaller(cx, fp);
265 if (caller && !caller->varobj) {
266 /* Called from a lightweight function. */
267 JS_ASSERT(caller->fun && !(caller->fun->flags & JSFUN_HEAVYWEIGHT));
269 /* Scope chain links from Call object to callee's parent. */
270 parent = OBJ_GET_PARENT(cx, JSVAL_TO_OBJECT(caller->argv[-2]));
271 if (!js_GetCallObject(cx, caller, parent))
272 return JS_FALSE;
273 }
275 if (!scopeobj) {
276 /* No scope object passed in: try to use the caller's scope chain. */
277 if (caller) {
278 /*
279 * Load caller->scopeChain after the conditional js_GetCallObject
280 * call above, which resets scopeChain as well as varobj.
281 */
282 scopeobj = caller->scopeChain;
283 } else {
284 /*
285 * Called from native code, so we don't know what scope object to
286 * use. We could use parent (see above), but Script.prototype.exec
287 * might be a shared/sealed "superglobal" method. A more general
288 * approach would use cx->globalObject, which will be the same as
289 * exec.__parent__ in the non-superglobal case. In the superglobal
290 * case it's the right object: the global, not the superglobal.
291 */
292 scopeobj = cx->globalObject;
293 }
294 }
296 return js_Execute(cx, scopeobj, script, caller, JSFRAME_EVAL, rval);
297 }
299 #if JS_HAS_XDR
301 static JSBool
302 XDRAtomListElement(JSXDRState *xdr, JSAtomListElement *ale)
303 {
304 jsval value;
305 jsatomid index;
307 if (xdr->mode == JSXDR_ENCODE)
308 value = ATOM_KEY(ALE_ATOM(ale));
310 index = ALE_INDEX(ale);
311 if (!JS_XDRUint32(xdr, &index))
312 return JS_FALSE;
313 ALE_SET_INDEX(ale, index);
315 if (!JS_XDRValue(xdr, &value))
316 return JS_FALSE;
318 if (xdr->mode == JSXDR_DECODE) {
319 if (!ALE_SET_ATOM(ale, js_AtomizeValue(xdr->cx, value, 0)))
320 return JS_FALSE;
321 }
322 return JS_TRUE;
323 }
325 static JSBool
326 XDRAtomMap(JSXDRState *xdr, JSAtomMap *map)
327 {
328 uint32 length;
329 uintN i;
330 JSBool ok;
332 if (xdr->mode == JSXDR_ENCODE)
333 length = map->length;
335 if (!JS_XDRUint32(xdr, &length))
336 return JS_FALSE;
338 if (xdr->mode == JSXDR_DECODE) {
339 JSContext *cx;
340 void *mark;
341 JSAtomList al;
342 JSAtomListElement *ale;
344 cx = xdr->cx;
345 mark = JS_ARENA_MARK(&cx->tempPool);
346 ATOM_LIST_INIT(&al);
347 for (i = 0; i < length; i++) {
348 JS_ARENA_ALLOCATE_TYPE(ale, JSAtomListElement, &cx->tempPool);
349 if (!ale ||
350 !XDRAtomListElement(xdr, ale)) {
351 if (!ale)
352 JS_ReportOutOfMemory(cx);
353 JS_ARENA_RELEASE(&cx->tempPool, mark);
354 return JS_FALSE;
355 }
356 ALE_SET_NEXT(ale, al.list);
357 al.count++;
358 al.list = ale;
359 }
360 ok = js_InitAtomMap(cx, map, &al);
361 JS_ARENA_RELEASE(&cx->tempPool, mark);
362 return ok;
363 }
365 if (xdr->mode == JSXDR_ENCODE) {
366 JSAtomListElement ale;
368 for (i = 0; i < map->length; i++) {
369 ALE_SET_ATOM(&ale, map->vector[i]);
370 ALE_SET_INDEX(&ale, i);
371 if (!XDRAtomListElement(xdr, &ale))
372 return JS_FALSE;
373 }
374 }
375 return JS_TRUE;
376 }
378 JSBool
379 js_XDRScript(JSXDRState *xdr, JSScript **scriptp, JSBool *hasMagic)
380 {
381 JSContext *cx;
382 JSScript *script, *newscript;
383 uint32 length, lineno, depth, magic, nsrcnotes, ntrynotes;
384 uint32 prologLength, version;
385 JSBool filenameWasSaved;
386 jssrcnote *notes, *sn;
388 cx = xdr->cx;
389 script = *scriptp;
390 nsrcnotes = ntrynotes = 0;
391 filenameWasSaved = JS_FALSE;
392 notes = NULL;
394 /*
395 * Encode prologLength and version after script->length (_2 or greater),
396 * but decode both new (>= _2) and old, prolog&version-free (_1) scripts.
397 * Version _3 supports principals serialization. Version _4 reorders the
398 * nsrcnotes and ntrynotes fields to come before everything except magic,
399 * length, prologLength, and version, so that srcnote and trynote storage
400 * can be allocated as part of the JSScript (along with bytecode storage).
401 */
402 if (xdr->mode == JSXDR_ENCODE)
403 magic = JSXDR_MAGIC_SCRIPT_CURRENT;
404 if (!JS_XDRUint32(xdr, &magic))
405 return JS_FALSE;
406 if (magic != JSXDR_MAGIC_SCRIPT_4 &&
407 magic != JSXDR_MAGIC_SCRIPT_3 &&
408 magic != JSXDR_MAGIC_SCRIPT_2 &&
409 magic != JSXDR_MAGIC_SCRIPT_1) {
410 if (!hasMagic) {
411 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
412 JSMSG_BAD_SCRIPT_MAGIC);
413 return JS_FALSE;
414 }
415 *hasMagic = JS_FALSE;
416 return JS_TRUE;
417 }
418 if (hasMagic)
419 *hasMagic = JS_TRUE;
421 if (xdr->mode == JSXDR_ENCODE) {
422 length = script->length;
423 prologLength = PTRDIFF(script->main, script->code, jsbytecode);
424 version = (int32)script->version;
425 lineno = (uint32)script->lineno;
426 depth = (uint32)script->depth;
428 /* Count the srcnotes, keeping notes pointing at the first one. */
429 notes = SCRIPT_NOTES(script);
430 for (sn = notes; !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn))
431 continue;
432 nsrcnotes = PTRDIFF(sn, notes, jssrcnote);
433 nsrcnotes++; /* room for the terminator */
435 /* Count the trynotes. */
436 if (script->trynotes) {
437 while (script->trynotes[ntrynotes].catchStart)
438 ntrynotes++;
439 ntrynotes++; /* room for the end marker */
440 }
441 }
443 if (!JS_XDRUint32(xdr, &length))
444 return JS_FALSE;
445 if (magic >= JSXDR_MAGIC_SCRIPT_2) {
446 if (!JS_XDRUint32(xdr, &prologLength))
447 return JS_FALSE;
448 if (!JS_XDRUint32(xdr, &version))
449 return JS_FALSE;
451 /* To fuse allocations, we need srcnote and trynote counts early. */
452 if (magic >= JSXDR_MAGIC_SCRIPT_4) {
453 if (!JS_XDRUint32(xdr, &nsrcnotes))
454 return JS_FALSE;
455 if (!JS_XDRUint32(xdr, &ntrynotes))
456 return JS_FALSE;
457 }
458 }
460 if (xdr->mode == JSXDR_DECODE) {
461 script = js_NewScript(cx, length, nsrcnotes, ntrynotes);
462 if (!script)
463 return JS_FALSE;
464 if (magic >= JSXDR_MAGIC_SCRIPT_2) {
465 script->main += prologLength;
466 script->version = (JSVersion) version;
468 /* If we know nsrcnotes, we allocated space for notes in script. */
469 if (magic >= JSXDR_MAGIC_SCRIPT_4)
470 notes = SCRIPT_NOTES(script);
471 }
472 *scriptp = script;
473 }
475 /*
476 * Control hereafter must goto error on failure, in order for the DECODE
477 * case to destroy script and conditionally free notes, which if non-null
478 * in the (DECODE and version < _4) case must point at a temporary vector
479 * allocated just below.
480 */
481 if (!JS_XDRBytes(xdr, (char *)script->code, length * sizeof(jsbytecode)) ||
482 !XDRAtomMap(xdr, &script->atomMap)) {
483 goto error;
484 }
486 if (magic < JSXDR_MAGIC_SCRIPT_4) {
487 if (!JS_XDRUint32(xdr, &nsrcnotes))
488 goto error;
489 if (xdr->mode == JSXDR_DECODE) {
490 notes = (jssrcnote *) JS_malloc(cx, nsrcnotes * sizeof(jssrcnote));
491 if (!notes)
492 goto error;
493 }
494 }
496 if (!JS_XDRBytes(xdr, (char *)notes, nsrcnotes * sizeof(jssrcnote)) ||
497 !JS_XDRCStringOrNull(xdr, (char **)&script->filename) ||
498 !JS_XDRUint32(xdr, &lineno) ||
499 !JS_XDRUint32(xdr, &depth) ||
500 (magic < JSXDR_MAGIC_SCRIPT_4 && !JS_XDRUint32(xdr, &ntrynotes))) {
501 goto error;
502 }
504 /* Script principals transcoding support comes with versions >= _3. */
505 if (magic >= JSXDR_MAGIC_SCRIPT_3) {
506 JSPrincipals *principals;
507 uint32 encodeable;
509 if (xdr->mode == JSXDR_ENCODE) {
510 principals = script->principals;
511 encodeable = (cx->runtime->principalsTranscoder != NULL);
512 if (!JS_XDRUint32(xdr, &encodeable))
513 goto error;
514 if (encodeable &&
515 !cx->runtime->principalsTranscoder(xdr, &principals)) {
516 goto error;
517 }
518 } else {
519 if (!JS_XDRUint32(xdr, &encodeable))
520 goto error;
521 if (encodeable) {
522 if (!cx->runtime->principalsTranscoder) {
523 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
524 JSMSG_CANT_DECODE_PRINCIPALS);
525 goto error;
526 }
527 if (!cx->runtime->principalsTranscoder(xdr, &principals))
528 goto error;
529 script->principals = principals;
530 }
531 }
532 }
534 if (xdr->mode == JSXDR_DECODE) {
535 const char *filename = script->filename;
536 if (filename) {
537 filename = js_SaveScriptFilename(cx, filename);
538 if (!filename)
539 goto error;
540 JS_free(cx, (void *) script->filename);
541 script->filename = filename;
542 filenameWasSaved = JS_TRUE;
543 }
544 script->lineno = (uintN)lineno;
545 script->depth = (uintN)depth;
547 if (magic < JSXDR_MAGIC_SCRIPT_4) {
548 /*
549 * Argh, we have to reallocate script, copy notes into the extra
550 * space after the bytecodes, and free the temporary notes vector.
551 * First, add enough slop to nsrcnotes so we can align the address
552 * after the srcnotes of the first trynote.
553 */
554 uint32 osrcnotes = nsrcnotes;
556 if (ntrynotes)
557 nsrcnotes += JSTRYNOTE_ALIGNMASK;
558 newscript = (JSScript *) JS_realloc(cx, script,
559 sizeof(JSScript) +
560 length * sizeof(jsbytecode) +
561 nsrcnotes * sizeof(jssrcnote) +
562 ntrynotes * sizeof(JSTryNote));
563 if (!newscript)
564 goto error;
566 *scriptp = script = newscript;
567 script->code = (jsbytecode *)(script + 1);
568 script->main = script->code + prologLength;
569 memcpy(script->code + length, notes, osrcnotes * sizeof(jssrcnote));
570 JS_free(cx, (void *) notes);
571 notes = NULL;
572 if (ntrynotes) {
573 script->trynotes = (JSTryNote *)
574 ((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
575 ~(jsword)JSTRYNOTE_ALIGNMASK);
576 }
577 }
578 }
580 while (ntrynotes) {
581 JSTryNote *tn = &script->trynotes[--ntrynotes];
582 uint32 start = (uint32) tn->start,
583 catchLength = (uint32) tn->length,
584 catchStart = (uint32) tn->catchStart;
586 if (!JS_XDRUint32(xdr, &start) ||
587 !JS_XDRUint32(xdr, &catchLength) ||
588 !JS_XDRUint32(xdr, &catchStart)) {
589 goto error;
590 }
591 tn->start = (ptrdiff_t) start;
592 tn->length = (ptrdiff_t) catchLength;
593 tn->catchStart = (ptrdiff_t) catchStart;
594 }
595 return JS_TRUE;
597 error:
598 if (xdr->mode == JSXDR_DECODE) {
599 if (script->filename && !filenameWasSaved) {
600 JS_free(cx, (void *) script->filename);
601 script->filename = NULL;
602 }
603 if (notes && magic < JSXDR_MAGIC_SCRIPT_4)
604 JS_free(cx, (void *) notes);
605 js_DestroyScript(cx, script);
606 *scriptp = NULL;
607 }
608 return JS_FALSE;
609 }
611 #if JS_HAS_XDR_FREEZE_THAW
612 /*
613 * These cannot be exposed to web content, and chrome does not need them, so
614 * we take them out of the Mozilla client altogether. Fortunately, there is
615 * no way to serialize a native function (see fun_xdrObject in jsfun.c).
616 */
618 static JSBool
619 script_freeze(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
620 jsval *rval)
621 {
622 JSXDRState *xdr;
623 JSScript *script;
624 JSBool ok, hasMagic;
625 uint32 len;
626 void *buf;
627 JSString *str;
629 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
630 return JS_FALSE;
631 script = (JSScript *) JS_GetPrivate(cx, obj);
632 if (!script)
633 return JS_TRUE;
635 /* create new XDR */
636 xdr = JS_XDRNewMem(cx, JSXDR_ENCODE);
637 if (!xdr)
638 return JS_FALSE;
640 /* write */
641 ok = js_XDRScript(xdr, &script, &hasMagic);
642 if (!ok)
643 goto out;
644 if (!hasMagic) {
645 *rval = JSVAL_VOID;
646 goto out;
647 }
649 buf = JS_XDRMemGetData(xdr, &len);
650 if (!buf) {
651 ok = JS_FALSE;
652 goto out;
653 }
655 JS_ASSERT((jsword)buf % sizeof(jschar) == 0);
656 len /= sizeof(jschar);
657 str = JS_NewUCStringCopyN(cx, (jschar *)buf, len);
658 if (!str) {
659 ok = JS_FALSE;
660 goto out;
661 }
663 #if IS_BIG_ENDIAN
664 {
665 jschar *chars;
666 uint32 i;
668 /* Swap bytes in Unichars to keep frozen strings machine-independent. */
669 chars = JS_GetStringChars(str);
670 for (i = 0; i < len; i++)
671 chars[i] = JSXDR_SWAB16(chars[i]);
672 }
673 #endif
674 *rval = STRING_TO_JSVAL(str);
676 out:
677 JS_XDRDestroy(xdr);
678 return ok;
679 }
681 static JSBool
682 script_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
683 jsval *rval)
684 {
685 JSXDRState *xdr;
686 JSString *str;
687 void *buf;
688 uint32 len;
689 JSScript *script, *oldscript;
690 JSBool ok, hasMagic;
692 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
693 return JS_FALSE;
695 if (argc == 0)
696 return JS_TRUE;
697 str = js_ValueToString(cx, argv[0]);
698 if (!str)
699 return JS_FALSE;
701 /* create new XDR */
702 xdr = JS_XDRNewMem(cx, JSXDR_DECODE);
703 if (!xdr)
704 return JS_FALSE;
706 buf = JS_GetStringChars(str);
707 len = JS_GetStringLength(str);
708 #if IS_BIG_ENDIAN
709 {
710 jschar *from, *to;
711 uint32 i;
713 /* Swap bytes in Unichars to keep frozen strings machine-independent. */
714 from = (jschar *)buf;
715 to = (jschar *) JS_malloc(cx, len * sizeof(jschar));
716 if (!to) {
717 JS_XDRDestroy(xdr);
718 return JS_FALSE;
719 }
720 for (i = 0; i < len; i++)
721 to[i] = JSXDR_SWAB16(from[i]);
722 buf = (char *)to;
723 }
724 #endif
725 len *= sizeof(jschar);
726 JS_XDRMemSetData(xdr, buf, len);
728 /* XXXbe should magic mismatch be error, or false return value? */
729 ok = js_XDRScript(xdr, &script, &hasMagic);
730 if (!ok)
731 goto out;
732 if (!hasMagic) {
733 *rval = JSVAL_FALSE;
734 goto out;
735 }
737 /* Swap script for obj's old script, if any. */
738 oldscript = (JSScript *) JS_GetPrivate(cx, obj);
739 ok = JS_SetPrivate(cx, obj, script);
740 if (!ok) {
741 JS_free(cx, script);
742 goto out;
743 }
744 if (oldscript)
745 js_DestroyScript(cx, oldscript);
747 script->object = obj;
748 js_CallNewScriptHook(cx, script, NULL);
750 out:
751 /*
752 * We reset the buffer to be NULL so that it doesn't free the chars
753 * memory owned by str (argv[0]).
754 */
755 JS_XDRMemSetData(xdr, NULL, 0);
756 JS_XDRDestroy(xdr);
757 #if IS_BIG_ENDIAN
758 JS_free(cx, buf);
759 #endif
760 *rval = JSVAL_TRUE;
761 return ok;
762 }
764 static const char js_thaw_str[] = "thaw";
766 #endif /* JS_HAS_XDR_FREEZE_THAW */
767 #endif /* JS_HAS_XDR */
769 static JSFunctionSpec script_methods[] = {
770 #if JS_HAS_TOSOURCE
771 {js_toSource_str, script_toSource, 0,0,0},
772 #endif
773 {js_toString_str, script_toString, 0,0,0},
774 {"compile", script_compile, 2,0,0},
775 {"exec", script_exec, 1,0,0},
776 #if JS_HAS_XDR_FREEZE_THAW
777 {"freeze", script_freeze, 0,0,0},
778 {js_thaw_str, script_thaw, 1,0,0},
779 #endif /* JS_HAS_XDR_FREEZE_THAW */
780 {0,0,0,0,0}
781 };
783 #endif /* JS_HAS_SCRIPT_OBJECT */
785 static void
786 script_finalize(JSContext *cx, JSObject *obj)
787 {
788 JSScript *script;
790 script = (JSScript *) JS_GetPrivate(cx, obj);
791 if (script)
792 js_DestroyScript(cx, script);
793 }
795 static JSBool
796 script_call(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
797 {
798 #if JS_HAS_SCRIPT_OBJECT
799 return script_exec(cx, JSVAL_TO_OBJECT(argv[-2]), argc, argv, rval);
800 #else
801 return JS_FALSE;
802 #endif
803 }
805 static uint32
806 script_mark(JSContext *cx, JSObject *obj, void *arg)
807 {
808 JSScript *script;
810 script = (JSScript *) JS_GetPrivate(cx, obj);
811 if (script)
812 js_MarkScript(cx, script, arg);
813 return 0;
814 }
816 JS_FRIEND_DATA(JSClass) js_ScriptClass = {
817 js_Script_str,
818 JSCLASS_HAS_PRIVATE,
819 JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
820 JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, script_finalize,
821 NULL, NULL, script_call, NULL,/*XXXbe xdr*/
822 NULL, NULL, script_mark, 0
823 };
825 #if JS_HAS_SCRIPT_OBJECT
827 static JSBool
828 Script(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
829 {
830 /* If not constructing, replace obj with a new Script object. */
831 if (!(cx->fp->flags & JSFRAME_CONSTRUCTING)) {
832 obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
833 if (!obj)
834 return JS_FALSE;
835 }
836 return script_compile(cx, obj, argc, argv, rval);
837 }
839 #if JS_HAS_XDR_FREEZE_THAW
841 static JSBool
842 script_static_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
843 jsval *rval)
844 {
845 obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
846 if (!obj)
847 return JS_FALSE;
848 if (!script_thaw(cx, obj, argc, argv, rval))
849 return JS_FALSE;
850 *rval = OBJECT_TO_JSVAL(obj);
851 return JS_TRUE;
852 }
854 static JSFunctionSpec script_static_methods[] = {
855 {js_thaw_str, script_static_thaw, 1,0,0},
856 {0,0,0,0,0}
857 };
859 #else /* !JS_HAS_XDR_FREEZE_THAW */
861 #define script_static_methods NULL
863 #endif /* !JS_HAS_XDR_FREEZE_THAW */
865 JSObject *
866 js_InitScriptClass(JSContext *cx, JSObject *obj)
867 {
868 return JS_InitClass(cx, obj, NULL, &js_ScriptClass, Script, 1,
869 NULL, script_methods, NULL, script_static_methods);
870 }
872 #endif /* JS_HAS_SCRIPT_OBJECT */
874 /*
875 * Shared script filename management.
876 */
877 static JSHashTable *script_filename_table;
878 #ifdef JS_THREADSAFE
879 static JSLock *script_filename_table_lock;
880 #endif
882 JS_STATIC_DLL_CALLBACK(int)
883 js_compare_strings(const void *k1, const void *k2)
884 {
885 return strcmp(k1, k2) == 0;
886 }
888 /* Shared with jsatom.c to save code space. */
889 extern void * JS_DLL_CALLBACK
890 js_alloc_table_space(void *priv, size_t size);
892 extern void JS_DLL_CALLBACK
893 js_free_table_space(void *priv, void *item);
895 /* NB: This struct overlays JSHashEntry -- see jshash.h, do not reorganize. */
896 typedef struct ScriptFilenameEntry {
897 JSHashEntry *next; /* hash chain linkage */
898 JSHashNumber keyHash; /* key hash function result */
899 const void *key; /* ptr to filename, below */
900 JSPackedBool mark; /* mark flag, for GC */
901 char filename[3]; /* two or more bytes, NUL-terminated */
902 } ScriptFilenameEntry;
904 JS_STATIC_DLL_CALLBACK(JSHashEntry *)
905 js_alloc_entry(void *priv, const void *key)
906 {
907 size_t nbytes = offsetof(ScriptFilenameEntry, filename) + strlen(key) + 1;
909 return (JSHashEntry *) malloc(JS_MAX(nbytes, sizeof(JSHashEntry)));
910 }
912 JS_STATIC_DLL_CALLBACK(void)
913 js_free_entry(void *priv, JSHashEntry *he, uintN flag)
914 {
915 if (flag != HT_FREE_ENTRY)
916 return;
917 free(he);
918 }
920 static JSHashAllocOps table_alloc_ops = {
921 js_alloc_table_space, js_free_table_space,
922 js_alloc_entry, js_free_entry
923 };
925 JSBool
926 js_InitScriptGlobals()
927 {
928 #ifdef JS_THREADSAFE
929 /* Must come through here once in primordial thread to init safely! */
930 if (!script_filename_table_lock) {
931 script_filename_table_lock = JS_NEW_LOCK();
932 if (!script_filename_table_lock)
933 return JS_FALSE;
934 }
935 #endif
936 if (!script_filename_table) {
937 JS_ACQUIRE_LOCK(script_filename_table_lock);
938 if (!script_filename_table) {
939 script_filename_table =
940 JS_NewHashTable(16, JS_HashString, js_compare_strings, NULL,
941 &table_alloc_ops, NULL);
942 }
943 JS_RELEASE_LOCK(script_filename_table_lock);
944 if (!script_filename_table)
945 return JS_FALSE;
946 }
947 return JS_TRUE;
948 }
950 void
951 js_FreeScriptGlobals()
952 {
953 if (script_filename_table) {
954 JS_HashTableDestroy(script_filename_table);
955 script_filename_table = NULL;
956 }
957 #ifdef JS_THREADSAFE
958 if (script_filename_table_lock) {
959 JS_DESTROY_LOCK(script_filename_table_lock);
960 script_filename_table_lock = NULL;
961 }
962 #endif
963 }
965 #ifdef DEBUG_brendan
966 size_t sft_savings = 0;
967 #endif
969 const char *
970 js_SaveScriptFilename(JSContext *cx, const char *filename)
971 {
972 JSHashTable *table;
973 JSHashNumber hash;
974 JSHashEntry **hep;
975 ScriptFilenameEntry *sfe;
977 JS_ACQUIRE_LOCK(script_filename_table_lock);
978 table = script_filename_table;
979 hash = JS_HashString(filename);
980 hep = JS_HashTableRawLookup(table, hash, filename);
981 sfe = (ScriptFilenameEntry *) *hep;
982 #ifdef DEBUG_brendan
983 if (sfe)
984 sft_savings += strlen(sfe->filename);
985 #endif
986 if (!sfe) {
987 sfe = (ScriptFilenameEntry *)
988 JS_HashTableRawAdd(table, hep, hash, filename, NULL);
989 if (sfe) {
990 sfe->key = strcpy(sfe->filename, filename);
991 JS_ASSERT(!sfe->mark);
992 }
993 }
994 JS_RELEASE_LOCK(script_filename_table_lock);
995 if (!sfe) {
996 JS_ReportOutOfMemory(cx);
997 return NULL;
998 }
999 return sfe->filename;
1000 }
1002 void
1003 js_MarkScriptFilename(const char *filename)
1004 {
1005 ScriptFilenameEntry *sfe;
1007 /*
1008 * Back up from filename by its offset within its hash table entry.
1009 * The sfe->key member, redundant given sfe->filename but required by
1010 * the old jshash.c code, here gives us a useful sanity check. This
1011 * assertion will very likely botch if someone tries to mark a string
1012 * that wasn't allocated as an sfe->filename.
1013 */
1014 sfe = (ScriptFilenameEntry *)
1015 (filename - offsetof(ScriptFilenameEntry, filename));
1016 JS_ASSERT(sfe->key == sfe->filename);
1017 sfe->mark = JS_TRUE;
1018 }
1020 JS_STATIC_DLL_CALLBACK(intN)
1021 js_script_filename_sweeper(JSHashEntry *he, intN i, void *arg)
1022 {
1023 ScriptFilenameEntry *sfe = (ScriptFilenameEntry *) he;
1025 if (!sfe->mark)
1026 return HT_ENUMERATE_REMOVE;
1027 sfe->mark = JS_FALSE;
1028 return HT_ENUMERATE_NEXT;
1029 }
1031 void
1032 js_SweepScriptFilenames(JSRuntime *rt)
1033 {
1034 JS_HashTableEnumerateEntries(script_filename_table,
1035 js_script_filename_sweeper,
1036 rt);
1037 #ifdef DEBUG_brendan
1038 printf("script filename table savings so far: %u\n", sft_savings);
1039 #endif
1040 }
1042 JSScript *
1043 js_NewScript(JSContext *cx, uint32 length, uint32 nsrcnotes, uint32 ntrynotes)
1044 {
1045 JSScript *script;
1047 /* Round up source note count to align script->trynotes for its type. */
1048 if (ntrynotes)
1049 nsrcnotes += JSTRYNOTE_ALIGNMASK;
1050 script = (JSScript *) JS_malloc(cx,
1051 sizeof(JSScript) +
1052 length * sizeof(jsbytecode) +
1053 nsrcnotes * sizeof(jssrcnote) +
1054 ntrynotes * sizeof(JSTryNote));
1055 if (!script)
1056 return NULL;
1057 memset(script, 0, sizeof(JSScript));
1058 script->code = script->main = (jsbytecode *)(script + 1);
1059 script->length = length;
1060 script->version = cx->version;
1061 if (ntrynotes) {
1062 script->trynotes = (JSTryNote *)
1063 ((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
1064 ~(jsword)JSTRYNOTE_ALIGNMASK);
1065 }
1066 return script;
1067 }
1069 JS_FRIEND_API(JSScript *)
1070 js_NewScriptFromCG(JSContext *cx, JSCodeGenerator *cg, JSFunction *fun)
1071 {
1072 uint32 mainLength, prologLength, nsrcnotes, ntrynotes;
1073 JSScript *script;
1074 const char *filename;
1076 mainLength = CG_OFFSET(cg);
1077 prologLength = CG_PROLOG_OFFSET(cg);
1078 CG_COUNT_FINAL_SRCNOTES(cg, nsrcnotes);
1079 CG_COUNT_FINAL_TRYNOTES(cg, ntrynotes);
1080 script = js_NewScript(cx, prologLength + mainLength, nsrcnotes, ntrynotes);
1081 if (!script)
1082 return NULL;
1084 /* Now that we have script, error control flow must go to label bad. */
1085 script->main += prologLength;
1086 memcpy(script->code, CG_PROLOG_BASE(cg), prologLength * sizeof(jsbytecode));
1087 memcpy(script->main, CG_BASE(cg), mainLength * sizeof(jsbytecode));
1088 if (!js_InitAtomMap(cx, &script->atomMap, &cg->atomList))
1089 goto bad;
1091 filename = cg->filename;
1092 if (filename) {
1093 script->filename = js_SaveScriptFilename(cx, filename);
1094 if (!script->filename)
1095 goto bad;
1096 }
1097 script->lineno = cg->firstLine;
1098 script->depth = cg->maxStackDepth;
1099 if (cg->principals) {
1100 script->principals = cg->principals;
1101 JSPRINCIPALS_HOLD(cx, script->principals);
1102 }
1104 if (!js_FinishTakingSrcNotes(cx, cg, SCRIPT_NOTES(script)))
1105 goto bad;
1106 if (script->trynotes)
1107 js_FinishTakingTryNotes(cx, cg, script->trynotes);
1109 /* Tell the debugger about this compiled script. */
1110 js_CallNewScriptHook(cx, script, fun);
1111 return script;
1113 bad:
1114 js_DestroyScript(cx, script);
1115 return NULL;
1116 }
1118 JS_FRIEND_API(void)
1119 js_CallNewScriptHook(JSContext *cx, JSScript *script, JSFunction *fun)
1120 {
1121 JSRuntime *rt;
1122 JSNewScriptHook hook;
1124 rt = cx->runtime;
1125 hook = rt->newScriptHook;
1126 if (hook) {
1127 /*
1128 * We use a dummy stack frame to protect the script from a GC caused
1129 * by debugger-hook execution.
1130 *
1131 * XXX We really need a way to manage local roots and such more
1132 * XXX automatically, at which point we can remove this one-off hack
1133 * XXX and others within the engine. See bug 40757 for discussion.
1134 */
1135 JSStackFrame dummy;
1137 memset(&dummy, 0, sizeof dummy);
1138 dummy.down = cx->fp;
1139 dummy.script = script;
1140 cx->fp = &dummy;
1142 hook(cx, script->filename, script->lineno, script, fun,
1143 rt->newScriptHookData);
1145 cx->fp = dummy.down;
1146 }
1147 }
1149 void
1150 js_DestroyScript(JSContext *cx, JSScript *script)
1151 {
1152 JSRuntime *rt;
1153 JSDestroyScriptHook hook;
1155 rt = cx->runtime;
1156 hook = rt->destroyScriptHook;
1157 if (hook)
1158 hook(cx, script, rt->destroyScriptHookData);
1160 JS_ClearScriptTraps(cx, script);
1161 js_FreeAtomMap(cx, &script->atomMap);
1162 if (script->principals)
1163 JSPRINCIPALS_DROP(cx, script->principals);
1164 JS_free(cx, script);
1165 }
1167 void
1168 js_MarkScript(JSContext *cx, JSScript *script, void *arg)
1169 {
1170 JSAtomMap *map;
1171 uintN i, length;
1172 JSAtom **vector;
1174 map = &script->atomMap;
1175 length = map->length;
1176 vector = map->vector;
1177 for (i = 0; i < length; i++)
1178 GC_MARK_ATOM(cx, vector[i], arg);
1180 if (script->filename)
1181 js_MarkScriptFilename(script->filename);
1182 }
1184 jssrcnote *
1185 js_GetSrcNote(JSScript *script, jsbytecode *pc)
1186 {
1187 jssrcnote *sn;
1188 ptrdiff_t offset, target;
1190 target = PTRDIFF(pc, script->code, jsbytecode);
1191 if ((uint32)target >= script->length)
1192 return NULL;
1193 offset = 0;
1194 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1195 offset += SN_DELTA(sn);
1196 if (offset == target && SN_IS_GETTABLE(sn))
1197 return sn;
1198 }
1199 return NULL;
1200 }
1202 uintN
1203 js_PCToLineNumber(JSContext *cx, JSScript *script, jsbytecode *pc)
1204 {
1205 JSAtom *atom;
1206 JSFunction *fun;
1207 uintN lineno;
1208 ptrdiff_t offset, target;
1209 jssrcnote *sn;
1210 JSSrcNoteType type;
1212 /*
1213 * Special case: function definition needs no line number note because
1214 * the function's script contains its starting line number.
1215 */
1216 if (*pc == JSOP_DEFFUN) {
1217 atom = GET_ATOM(cx, script, pc);
1218 fun = (JSFunction *) JS_GetPrivate(cx, ATOM_TO_OBJECT(atom));
1219 return fun->script->lineno;
1220 }
1222 /*
1223 * General case: walk through source notes accumulating their deltas,
1224 * keeping track of line-number notes, until we pass the note for pc's
1225 * offset within script->code.
1226 */
1227 lineno = script->lineno;
1228 offset = 0;
1229 target = PTRDIFF(pc, script->code, jsbytecode);
1230 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1231 offset += SN_DELTA(sn);
1232 type = (JSSrcNoteType) SN_TYPE(sn);
1233 if (type == SRC_SETLINE) {
1234 if (offset <= target)
1235 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1236 } else if (type == SRC_NEWLINE) {
1237 if (offset <= target)
1238 lineno++;
1239 }
1240 if (offset > target)
1241 break;
1242 }
1243 return lineno;
1244 }
1246 jsbytecode *
1247 js_LineNumberToPC(JSScript *script, uintN target)
1248 {
1249 ptrdiff_t offset;
1250 uintN lineno;
1251 jssrcnote *sn;
1252 JSSrcNoteType type;
1254 offset = 0;
1255 lineno = script->lineno;
1256 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1257 if (lineno >= target)
1258 break;
1259 offset += SN_DELTA(sn);
1260 type = (JSSrcNoteType) SN_TYPE(sn);
1261 if (type == SRC_SETLINE) {
1262 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1263 } else if (type == SRC_NEWLINE) {
1264 lineno++;
1265 }
1266 }
1267 return script->code + offset;
1268 }
1270 uintN
1271 js_GetScriptLineExtent(JSScript *script)
1272 {
1273 uintN lineno;
1274 jssrcnote *sn;
1275 JSSrcNoteType type;
1277 lineno = script->lineno;
1278 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1279 type = (JSSrcNoteType) SN_TYPE(sn);
1280 if (type == SRC_SETLINE) {
1281 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1282 } else if (type == SRC_NEWLINE) {
1283 lineno++;
1284 }
1285 }
1286 return 1 + lineno - script->lineno;
1287 }