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 /*
205 * Compile the new script using the caller's scope chain, a la eval().
206 * Unlike jsobj.c:obj_eval, however, we do not set JSFRAME_EVAL in fp's
207 * flags, because compilation is here separated from execution, and the
208 * run-time scope chain may not match the compile-time. JSFRAME_EVAL is
209 * tested in jsemit.c and jsscan.c to optimize based on identity of run-
210 * and compile-time scope.
211 */
212 script = JS_CompileUCScriptForPrincipals(cx, scopeobj, principals,
213 JSSTRING_CHARS(str),
214 JSSTRING_LENGTH(str),
215 file, line);
216 if (!script)
217 return JS_FALSE;
219 /* Swap script for obj's old script, if any. */
220 oldscript = (JSScript *) JS_GetPrivate(cx, obj);
221 if (!JS_SetPrivate(cx, obj, script)) {
222 js_DestroyScript(cx, script);
223 return JS_FALSE;
224 }
225 if (oldscript)
226 js_DestroyScript(cx, oldscript);
228 script->object = obj;
229 out:
230 /* Return the object. */
231 *rval = OBJECT_TO_JSVAL(obj);
232 return JS_TRUE;
233 }
235 static JSBool
236 script_exec(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
237 {
238 JSScript *script;
239 JSObject *scopeobj, *parent;
240 JSStackFrame *fp, *caller;
242 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
243 return JS_FALSE;
244 script = (JSScript *) JS_GetPrivate(cx, obj);
245 if (!script)
246 return JS_TRUE;
248 scopeobj = NULL;
249 if (argc) {
250 if (!js_ValueToObject(cx, argv[0], &scopeobj))
251 return JS_FALSE;
252 argv[0] = OBJECT_TO_JSVAL(scopeobj);
253 }
255 /*
256 * Emulate eval() by using caller's this, var object, sharp array, etc.,
257 * all propagated by js_Execute via a non-null fourth (down) argument to
258 * js_Execute. If there is no scripted caller, js_Execute uses its second
259 * (chain) argument to set the exec frame's varobj, thisp, and scopeChain.
260 *
261 * Unlike eval, which the compiler detects, Script.prototype.exec may be
262 * called from a lightweight function, or even from native code (in which
263 * case fp->varobj and fp->scopeChain are null). If exec is called from
264 * a lightweight function, we will need to get a Call object representing
265 * its frame, to act as the var object and scope chain head.
266 */
267 fp = cx->fp;
268 caller = JS_GetScriptedCaller(cx, fp);
269 if (caller && !caller->varobj) {
270 /* Called from a lightweight function. */
271 JS_ASSERT(caller->fun && !(caller->fun->flags & JSFUN_HEAVYWEIGHT));
273 /* Scope chain links from Call object to callee's parent. */
274 parent = OBJ_GET_PARENT(cx, JSVAL_TO_OBJECT(caller->argv[-2]));
275 if (!js_GetCallObject(cx, caller, parent))
276 return JS_FALSE;
277 }
279 if (!scopeobj) {
280 /* No scope object passed in: try to use the caller's scope chain. */
281 if (caller) {
282 /*
283 * Load caller->scopeChain after the conditional js_GetCallObject
284 * call above, which resets scopeChain as well as varobj.
285 */
286 scopeobj = caller->scopeChain;
287 } else {
288 /*
289 * Called from native code, so we don't know what scope object to
290 * use. We could use parent (see above), but Script.prototype.exec
291 * might be a shared/sealed "superglobal" method. A more general
292 * approach would use cx->globalObject, which will be the same as
293 * exec.__parent__ in the non-superglobal case. In the superglobal
294 * case it's the right object: the global, not the superglobal.
295 */
296 scopeobj = cx->globalObject;
297 }
298 }
300 return js_Execute(cx, scopeobj, script, caller, JSFRAME_EVAL, rval);
301 }
303 #if JS_HAS_XDR
305 static JSBool
306 XDRAtomListElement(JSXDRState *xdr, JSAtomListElement *ale)
307 {
308 jsval value;
309 jsatomid index;
311 if (xdr->mode == JSXDR_ENCODE)
312 value = ATOM_KEY(ALE_ATOM(ale));
314 index = ALE_INDEX(ale);
315 if (!JS_XDRUint32(xdr, &index))
316 return JS_FALSE;
317 ALE_SET_INDEX(ale, index);
319 if (!JS_XDRValue(xdr, &value))
320 return JS_FALSE;
322 if (xdr->mode == JSXDR_DECODE) {
323 if (!ALE_SET_ATOM(ale, js_AtomizeValue(xdr->cx, value, 0)))
324 return JS_FALSE;
325 }
326 return JS_TRUE;
327 }
329 static JSBool
330 XDRAtomMap(JSXDRState *xdr, JSAtomMap *map)
331 {
332 uint32 length;
333 uintN i;
334 JSBool ok;
336 if (xdr->mode == JSXDR_ENCODE)
337 length = map->length;
339 if (!JS_XDRUint32(xdr, &length))
340 return JS_FALSE;
342 if (xdr->mode == JSXDR_DECODE) {
343 JSContext *cx;
344 void *mark;
345 JSAtomList al;
346 JSAtomListElement *ale;
348 cx = xdr->cx;
349 mark = JS_ARENA_MARK(&cx->tempPool);
350 ATOM_LIST_INIT(&al);
351 for (i = 0; i < length; i++) {
352 JS_ARENA_ALLOCATE_TYPE(ale, JSAtomListElement, &cx->tempPool);
353 if (!ale ||
354 !XDRAtomListElement(xdr, ale)) {
355 if (!ale)
356 JS_ReportOutOfMemory(cx);
357 JS_ARENA_RELEASE(&cx->tempPool, mark);
358 return JS_FALSE;
359 }
360 ALE_SET_NEXT(ale, al.list);
361 al.count++;
362 al.list = ale;
363 }
364 ok = js_InitAtomMap(cx, map, &al);
365 JS_ARENA_RELEASE(&cx->tempPool, mark);
366 return ok;
367 }
369 if (xdr->mode == JSXDR_ENCODE) {
370 JSAtomListElement ale;
372 for (i = 0; i < map->length; i++) {
373 ALE_SET_ATOM(&ale, map->vector[i]);
374 ALE_SET_INDEX(&ale, i);
375 if (!XDRAtomListElement(xdr, &ale))
376 return JS_FALSE;
377 }
378 }
379 return JS_TRUE;
380 }
382 JSBool
383 js_XDRScript(JSXDRState *xdr, JSScript **scriptp, JSBool *hasMagic)
384 {
385 JSContext *cx;
386 JSScript *script, *newscript;
387 uint32 length, lineno, depth, magic, nsrcnotes, ntrynotes;
388 uint32 prologLength, version;
389 JSBool filenameWasSaved;
390 jssrcnote *notes, *sn;
392 cx = xdr->cx;
393 script = *scriptp;
394 nsrcnotes = ntrynotes = 0;
395 filenameWasSaved = JS_FALSE;
396 notes = NULL;
398 /*
399 * Encode prologLength and version after script->length (_2 or greater),
400 * but decode both new (>= _2) and old, prolog&version-free (_1) scripts.
401 * Version _3 supports principals serialization. Version _4 reorders the
402 * nsrcnotes and ntrynotes fields to come before everything except magic,
403 * length, prologLength, and version, so that srcnote and trynote storage
404 * can be allocated as part of the JSScript (along with bytecode storage).
405 */
406 if (xdr->mode == JSXDR_ENCODE)
407 magic = JSXDR_MAGIC_SCRIPT_CURRENT;
408 if (!JS_XDRUint32(xdr, &magic))
409 return JS_FALSE;
410 if (magic != JSXDR_MAGIC_SCRIPT_4 &&
411 magic != JSXDR_MAGIC_SCRIPT_3 &&
412 magic != JSXDR_MAGIC_SCRIPT_2 &&
413 magic != JSXDR_MAGIC_SCRIPT_1) {
414 if (!hasMagic) {
415 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
416 JSMSG_BAD_SCRIPT_MAGIC);
417 return JS_FALSE;
418 }
419 *hasMagic = JS_FALSE;
420 return JS_TRUE;
421 }
422 if (hasMagic)
423 *hasMagic = JS_TRUE;
425 if (xdr->mode == JSXDR_ENCODE) {
426 length = script->length;
427 prologLength = PTRDIFF(script->main, script->code, jsbytecode);
428 JS_ASSERT((int16)script->version != JSVERSION_UNKNOWN);
429 version = (uint32)script->version | (script->numGlobalVars << 16);
430 lineno = (uint32)script->lineno;
431 depth = (uint32)script->depth;
433 /* Count the srcnotes, keeping notes pointing at the first one. */
434 notes = SCRIPT_NOTES(script);
435 for (sn = notes; !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn))
436 continue;
437 nsrcnotes = PTRDIFF(sn, notes, jssrcnote);
438 nsrcnotes++; /* room for the terminator */
440 /* Count the trynotes. */
441 if (script->trynotes) {
442 while (script->trynotes[ntrynotes].catchStart)
443 ntrynotes++;
444 ntrynotes++; /* room for the end marker */
445 }
446 }
448 if (!JS_XDRUint32(xdr, &length))
449 return JS_FALSE;
450 if (magic >= JSXDR_MAGIC_SCRIPT_2) {
451 if (!JS_XDRUint32(xdr, &prologLength))
452 return JS_FALSE;
453 if (!JS_XDRUint32(xdr, &version))
454 return JS_FALSE;
456 /* To fuse allocations, we need srcnote and trynote counts early. */
457 if (magic >= JSXDR_MAGIC_SCRIPT_4) {
458 if (!JS_XDRUint32(xdr, &nsrcnotes))
459 return JS_FALSE;
460 if (!JS_XDRUint32(xdr, &ntrynotes))
461 return JS_FALSE;
462 }
463 }
465 if (xdr->mode == JSXDR_DECODE) {
466 script = js_NewScript(cx, length, nsrcnotes, ntrynotes);
467 if (!script)
468 return JS_FALSE;
469 if (magic >= JSXDR_MAGIC_SCRIPT_2) {
470 script->main += prologLength;
471 script->version = (JSVersion) (version & 0xffff);
472 script->numGlobalVars = (uint16) (version >> 16);
474 /* If we know nsrcnotes, we allocated space for notes in script. */
475 if (magic >= JSXDR_MAGIC_SCRIPT_4)
476 notes = SCRIPT_NOTES(script);
477 }
478 *scriptp = script;
479 }
481 /*
482 * Control hereafter must goto error on failure, in order for the DECODE
483 * case to destroy script and conditionally free notes, which if non-null
484 * in the (DECODE and magic < _4) case must point at a temporary vector
485 * allocated just below.
486 */
487 if (!JS_XDRBytes(xdr, (char *)script->code, length * sizeof(jsbytecode)) ||
488 !XDRAtomMap(xdr, &script->atomMap)) {
489 goto error;
490 }
492 if (magic < JSXDR_MAGIC_SCRIPT_4) {
493 if (!JS_XDRUint32(xdr, &nsrcnotes))
494 goto error;
495 if (xdr->mode == JSXDR_DECODE) {
496 notes = (jssrcnote *) JS_malloc(cx, nsrcnotes * sizeof(jssrcnote));
497 if (!notes)
498 goto error;
499 }
500 }
502 if (!JS_XDRBytes(xdr, (char *)notes, nsrcnotes * sizeof(jssrcnote)) ||
503 !JS_XDRCStringOrNull(xdr, (char **)&script->filename) ||
504 !JS_XDRUint32(xdr, &lineno) ||
505 !JS_XDRUint32(xdr, &depth) ||
506 (magic < JSXDR_MAGIC_SCRIPT_4 && !JS_XDRUint32(xdr, &ntrynotes))) {
507 goto error;
508 }
510 /* Script principals transcoding support comes with versions >= _3. */
511 if (magic >= JSXDR_MAGIC_SCRIPT_3) {
512 JSPrincipals *principals;
513 uint32 encodeable;
515 if (xdr->mode == JSXDR_ENCODE) {
516 principals = script->principals;
517 encodeable = (cx->runtime->principalsTranscoder != NULL);
518 if (!JS_XDRUint32(xdr, &encodeable))
519 goto error;
520 if (encodeable &&
521 !cx->runtime->principalsTranscoder(xdr, &principals)) {
522 goto error;
523 }
524 } else {
525 if (!JS_XDRUint32(xdr, &encodeable))
526 goto error;
527 if (encodeable) {
528 if (!cx->runtime->principalsTranscoder) {
529 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
530 JSMSG_CANT_DECODE_PRINCIPALS);
531 goto error;
532 }
533 if (!cx->runtime->principalsTranscoder(xdr, &principals))
534 goto error;
535 script->principals = principals;
536 }
537 }
538 }
540 if (xdr->mode == JSXDR_DECODE) {
541 const char *filename = script->filename;
542 if (filename) {
543 filename = js_SaveScriptFilename(cx, filename);
544 if (!filename)
545 goto error;
546 JS_free(cx, (void *) script->filename);
547 script->filename = filename;
548 filenameWasSaved = JS_TRUE;
549 }
550 script->lineno = (uintN)lineno;
551 script->depth = (uintN)depth;
553 if (magic < JSXDR_MAGIC_SCRIPT_4) {
554 /*
555 * Argh, we have to reallocate script, copy notes into the extra
556 * space after the bytecodes, and free the temporary notes vector.
557 * First, add enough slop to nsrcnotes so we can align the address
558 * after the srcnotes of the first trynote.
559 */
560 uint32 osrcnotes = nsrcnotes;
562 if (ntrynotes)
563 nsrcnotes += JSTRYNOTE_ALIGNMASK;
564 newscript = (JSScript *) JS_realloc(cx, script,
565 sizeof(JSScript) +
566 length * sizeof(jsbytecode) +
567 nsrcnotes * sizeof(jssrcnote) +
568 ntrynotes * sizeof(JSTryNote));
569 if (!newscript)
570 goto error;
572 *scriptp = script = newscript;
573 script->code = (jsbytecode *)(script + 1);
574 script->main = script->code + prologLength;
575 memcpy(script->code + length, notes, osrcnotes * sizeof(jssrcnote));
576 JS_free(cx, (void *) notes);
577 notes = NULL;
578 if (ntrynotes) {
579 script->trynotes = (JSTryNote *)
580 ((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
581 ~(jsword)JSTRYNOTE_ALIGNMASK);
582 memset(script->trynotes, 0, ntrynotes * sizeof(JSTryNote));
583 }
584 }
585 }
587 while (ntrynotes) {
588 JSTryNote *tn = &script->trynotes[--ntrynotes];
589 uint32 start = (uint32) tn->start,
590 catchLength = (uint32) tn->length,
591 catchStart = (uint32) tn->catchStart;
593 if (!JS_XDRUint32(xdr, &start) ||
594 !JS_XDRUint32(xdr, &catchLength) ||
595 !JS_XDRUint32(xdr, &catchStart)) {
596 goto error;
597 }
598 tn->start = (ptrdiff_t) start;
599 tn->length = (ptrdiff_t) catchLength;
600 tn->catchStart = (ptrdiff_t) catchStart;
601 }
602 return JS_TRUE;
604 error:
605 if (xdr->mode == JSXDR_DECODE) {
606 if (script->filename && !filenameWasSaved) {
607 JS_free(cx, (void *) script->filename);
608 script->filename = NULL;
609 }
610 if (notes && magic < JSXDR_MAGIC_SCRIPT_4)
611 JS_free(cx, (void *) notes);
612 js_DestroyScript(cx, script);
613 *scriptp = NULL;
614 }
615 return JS_FALSE;
616 }
618 #if JS_HAS_XDR_FREEZE_THAW
619 /*
620 * These cannot be exposed to web content, and chrome does not need them, so
621 * we take them out of the Mozilla client altogether. Fortunately, there is
622 * no way to serialize a native function (see fun_xdrObject in jsfun.c).
623 */
625 static JSBool
626 script_freeze(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
627 jsval *rval)
628 {
629 JSXDRState *xdr;
630 JSScript *script;
631 JSBool ok, hasMagic;
632 uint32 len;
633 void *buf;
634 JSString *str;
636 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
637 return JS_FALSE;
638 script = (JSScript *) JS_GetPrivate(cx, obj);
639 if (!script)
640 return JS_TRUE;
642 /* create new XDR */
643 xdr = JS_XDRNewMem(cx, JSXDR_ENCODE);
644 if (!xdr)
645 return JS_FALSE;
647 /* write */
648 ok = js_XDRScript(xdr, &script, &hasMagic);
649 if (!ok)
650 goto out;
651 if (!hasMagic) {
652 *rval = JSVAL_VOID;
653 goto out;
654 }
656 buf = JS_XDRMemGetData(xdr, &len);
657 if (!buf) {
658 ok = JS_FALSE;
659 goto out;
660 }
662 JS_ASSERT((jsword)buf % sizeof(jschar) == 0);
663 len /= sizeof(jschar);
664 str = JS_NewUCStringCopyN(cx, (jschar *)buf, len);
665 if (!str) {
666 ok = JS_FALSE;
667 goto out;
668 }
670 #if IS_BIG_ENDIAN
671 {
672 jschar *chars;
673 uint32 i;
675 /* Swap bytes in Unichars to keep frozen strings machine-independent. */
676 chars = JS_GetStringChars(str);
677 for (i = 0; i < len; i++)
678 chars[i] = JSXDR_SWAB16(chars[i]);
679 }
680 #endif
681 *rval = STRING_TO_JSVAL(str);
683 out:
684 JS_XDRDestroy(xdr);
685 return ok;
686 }
688 static JSBool
689 script_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
690 jsval *rval)
691 {
692 JSXDRState *xdr;
693 JSString *str;
694 void *buf;
695 uint32 len;
696 JSScript *script, *oldscript;
697 JSBool ok, hasMagic;
699 if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
700 return JS_FALSE;
702 if (argc == 0)
703 return JS_TRUE;
704 str = js_ValueToString(cx, argv[0]);
705 if (!str)
706 return JS_FALSE;
708 /* create new XDR */
709 xdr = JS_XDRNewMem(cx, JSXDR_DECODE);
710 if (!xdr)
711 return JS_FALSE;
713 buf = JS_GetStringChars(str);
714 len = JS_GetStringLength(str);
715 #if IS_BIG_ENDIAN
716 {
717 jschar *from, *to;
718 uint32 i;
720 /* Swap bytes in Unichars to keep frozen strings machine-independent. */
721 from = (jschar *)buf;
722 to = (jschar *) JS_malloc(cx, len * sizeof(jschar));
723 if (!to) {
724 JS_XDRDestroy(xdr);
725 return JS_FALSE;
726 }
727 for (i = 0; i < len; i++)
728 to[i] = JSXDR_SWAB16(from[i]);
729 buf = (char *)to;
730 }
731 #endif
732 len *= sizeof(jschar);
733 JS_XDRMemSetData(xdr, buf, len);
735 /* XXXbe should magic mismatch be error, or false return value? */
736 ok = js_XDRScript(xdr, &script, &hasMagic);
737 if (!ok)
738 goto out;
739 if (!hasMagic) {
740 *rval = JSVAL_FALSE;
741 goto out;
742 }
744 /* Swap script for obj's old script, if any. */
745 oldscript = (JSScript *) JS_GetPrivate(cx, obj);
746 ok = JS_SetPrivate(cx, obj, script);
747 if (!ok) {
748 JS_free(cx, script);
749 goto out;
750 }
751 if (oldscript)
752 js_DestroyScript(cx, oldscript);
754 script->object = obj;
755 js_CallNewScriptHook(cx, script, NULL);
757 out:
758 /*
759 * We reset the buffer to be NULL so that it doesn't free the chars
760 * memory owned by str (argv[0]).
761 */
762 JS_XDRMemSetData(xdr, NULL, 0);
763 JS_XDRDestroy(xdr);
764 #if IS_BIG_ENDIAN
765 JS_free(cx, buf);
766 #endif
767 *rval = JSVAL_TRUE;
768 return ok;
769 }
771 static const char js_thaw_str[] = "thaw";
773 #endif /* JS_HAS_XDR_FREEZE_THAW */
774 #endif /* JS_HAS_XDR */
776 static JSFunctionSpec script_methods[] = {
777 #if JS_HAS_TOSOURCE
778 {js_toSource_str, script_toSource, 0,0,0},
779 #endif
780 {js_toString_str, script_toString, 0,0,0},
781 {"compile", script_compile, 2,0,0},
782 {"exec", script_exec, 1,0,0},
783 #if JS_HAS_XDR_FREEZE_THAW
784 {"freeze", script_freeze, 0,0,0},
785 {js_thaw_str, script_thaw, 1,0,0},
786 #endif /* JS_HAS_XDR_FREEZE_THAW */
787 {0,0,0,0,0}
788 };
790 #endif /* JS_HAS_SCRIPT_OBJECT */
792 static void
793 script_finalize(JSContext *cx, JSObject *obj)
794 {
795 JSScript *script;
797 script = (JSScript *) JS_GetPrivate(cx, obj);
798 if (script)
799 js_DestroyScript(cx, script);
800 }
802 static JSBool
803 script_call(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
804 {
805 #if JS_HAS_SCRIPT_OBJECT
806 return script_exec(cx, JSVAL_TO_OBJECT(argv[-2]), argc, argv, rval);
807 #else
808 return JS_FALSE;
809 #endif
810 }
812 static uint32
813 script_mark(JSContext *cx, JSObject *obj, void *arg)
814 {
815 JSScript *script;
817 script = (JSScript *) JS_GetPrivate(cx, obj);
818 if (script)
819 js_MarkScript(cx, script, arg);
820 return 0;
821 }
823 JS_FRIEND_DATA(JSClass) js_ScriptClass = {
824 js_Script_str,
825 JSCLASS_HAS_PRIVATE,
826 JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
827 JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, script_finalize,
828 NULL, NULL, script_call, NULL,/*XXXbe xdr*/
829 NULL, NULL, script_mark, 0
830 };
832 #if JS_HAS_SCRIPT_OBJECT
834 static JSBool
835 Script(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
836 {
837 /* If not constructing, replace obj with a new Script object. */
838 if (!(cx->fp->flags & JSFRAME_CONSTRUCTING)) {
839 obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
840 if (!obj)
841 return JS_FALSE;
842 }
843 return script_compile(cx, obj, argc, argv, rval);
844 }
846 #if JS_HAS_XDR_FREEZE_THAW
848 static JSBool
849 script_static_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
850 jsval *rval)
851 {
852 obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
853 if (!obj)
854 return JS_FALSE;
855 if (!script_thaw(cx, obj, argc, argv, rval))
856 return JS_FALSE;
857 *rval = OBJECT_TO_JSVAL(obj);
858 return JS_TRUE;
859 }
861 static JSFunctionSpec script_static_methods[] = {
862 {js_thaw_str, script_static_thaw, 1,0,0},
863 {0,0,0,0,0}
864 };
866 #else /* !JS_HAS_XDR_FREEZE_THAW */
868 #define script_static_methods NULL
870 #endif /* !JS_HAS_XDR_FREEZE_THAW */
872 JSObject *
873 js_InitScriptClass(JSContext *cx, JSObject *obj)
874 {
875 return JS_InitClass(cx, obj, NULL, &js_ScriptClass, Script, 1,
876 NULL, script_methods, NULL, script_static_methods);
877 }
879 #endif /* JS_HAS_SCRIPT_OBJECT */
881 /*
882 * Shared script filename management.
883 */
884 JS_STATIC_DLL_CALLBACK(int)
885 js_compare_strings(const void *k1, const void *k2)
886 {
887 return strcmp(k1, k2) == 0;
888 }
890 /* Shared with jsatom.c to save code space. */
891 extern void * JS_DLL_CALLBACK
892 js_alloc_table_space(void *priv, size_t size);
894 extern void JS_DLL_CALLBACK
895 js_free_table_space(void *priv, void *item);
897 /* NB: This struct overlays JSHashEntry -- see jshash.h, do not reorganize. */
898 typedef struct ScriptFilenameEntry {
899 JSHashEntry *next; /* hash chain linkage */
900 JSHashNumber keyHash; /* key hash function result */
901 const void *key; /* ptr to filename, below */
902 JSPackedBool mark; /* mark flag, for GC */
903 char filename[3]; /* two or more bytes, NUL-terminated */
904 } ScriptFilenameEntry;
906 JS_STATIC_DLL_CALLBACK(JSHashEntry *)
907 js_alloc_sftbl_entry(void *priv, const void *key)
908 {
909 size_t nbytes = offsetof(ScriptFilenameEntry, filename) + strlen(key) + 1;
911 return (JSHashEntry *) malloc(JS_MAX(nbytes, sizeof(JSHashEntry)));
912 }
914 JS_STATIC_DLL_CALLBACK(void)
915 js_free_sftbl_entry(void *priv, JSHashEntry *he, uintN flag)
916 {
917 if (flag != HT_FREE_ENTRY)
918 return;
919 free(he);
920 }
922 static JSHashAllocOps table_alloc_ops = {
923 js_alloc_table_space, js_free_table_space,
924 js_alloc_sftbl_entry, js_free_sftbl_entry
925 };
927 JSBool
928 js_InitRuntimeScriptState(JSContext *cx)
929 {
930 JSRuntime *rt = cx->runtime;
932 #ifdef JS_THREADSAFE
933 /* Must come through here once in primordial thread to init safely! */
934 if (!rt->scriptFilenameTableLock) {
935 rt->scriptFilenameTableLock = JS_NEW_LOCK();
936 if (!rt->scriptFilenameTableLock)
937 return JS_FALSE;
938 }
939 #endif
940 if (!rt->scriptFilenameTable) {
941 JS_ACQUIRE_LOCK(rt->scriptFilenameTableLock);
942 if (!rt->scriptFilenameTable) {
943 rt->scriptFilenameTable =
944 JS_NewHashTable(16, JS_HashString, js_compare_strings, NULL,
945 &table_alloc_ops, NULL);
946 }
947 JS_RELEASE_LOCK(rt->scriptFilenameTableLock);
948 if (!rt->scriptFilenameTable) {
949 js_FinishRuntimeScriptState(cx); /* free lock if threadsafe */
950 return JS_FALSE;
951 }
952 }
953 return JS_TRUE;
954 }
956 void
957 js_FinishRuntimeScriptState(JSContext *cx)
958 {
959 JSRuntime *rt = cx->runtime;
961 if (rt->scriptFilenameTable) {
962 JS_HashTableDestroy(rt->scriptFilenameTable);
963 rt->scriptFilenameTable = NULL;
964 }
965 #ifdef JS_THREADSAFE
966 if (rt->scriptFilenameTableLock) {
967 JS_DESTROY_LOCK(rt->scriptFilenameTableLock);
968 rt->scriptFilenameTableLock = NULL;
969 }
970 #endif
971 }
973 #ifdef DEBUG_brendan
974 size_t sftbl_savings = 0;
975 #endif
977 const char *
978 js_SaveScriptFilename(JSContext *cx, const char *filename)
979 {
980 JSRuntime *rt = cx->runtime;
981 JSHashTable *table;
982 JSHashNumber hash;
983 JSHashEntry **hep;
984 ScriptFilenameEntry *sfe;
986 JS_ACQUIRE_LOCK(rt->scriptFilenameTableLock);
987 table = rt->scriptFilenameTable;
988 hash = JS_HashString(filename);
989 hep = JS_HashTableRawLookup(table, hash, filename);
990 sfe = (ScriptFilenameEntry *) *hep;
991 #ifdef DEBUG_brendan
992 if (sfe)
993 sftbl_savings += strlen(sfe->filename);
994 #endif
995 if (!sfe) {
996 sfe = (ScriptFilenameEntry *)
997 JS_HashTableRawAdd(table, hep, hash, filename, NULL);
998 if (sfe) {
999 sfe->key = strcpy(sfe->filename, filename);
1000 JS_ASSERT(!sfe->mark);
1001 }
1002 }
1003 JS_RELEASE_LOCK(rt->scriptFilenameTableLock);
1004 if (!sfe) {
1005 JS_ReportOutOfMemory(cx);
1006 return NULL;
1007 }
1008 return sfe->filename;
1009 }
1011 void
1012 js_MarkScriptFilename(const char *filename)
1013 {
1014 ScriptFilenameEntry *sfe;
1016 /*
1017 * Back up from filename by its offset within its hash table entry.
1018 * The sfe->key member, redundant given sfe->filename but required by
1019 * the old jshash.c code, here gives us a useful sanity check. This
1020 * assertion will very likely botch if someone tries to mark a string
1021 * that wasn't allocated as an sfe->filename.
1022 */
1023 sfe = (ScriptFilenameEntry *)
1024 (filename - offsetof(ScriptFilenameEntry, filename));
1025 JS_ASSERT(sfe->key == sfe->filename);
1026 sfe->mark = JS_TRUE;
1027 }
1029 JS_STATIC_DLL_CALLBACK(intN)
1030 js_script_filename_sweeper(JSHashEntry *he, intN i, void *arg)
1031 {
1032 ScriptFilenameEntry *sfe = (ScriptFilenameEntry *) he;
1034 if (!sfe->mark)
1035 return HT_ENUMERATE_REMOVE;
1036 sfe->mark = JS_FALSE;
1037 return HT_ENUMERATE_NEXT;
1038 }
1040 void
1041 js_SweepScriptFilenames(JSRuntime *rt)
1042 {
1043 JS_HashTableEnumerateEntries(rt->scriptFilenameTable,
1044 js_script_filename_sweeper,
1045 rt);
1046 #ifdef DEBUG_brendan
1047 printf("script filename table savings so far: %u\n", sftbl_savings);
1048 #endif
1049 }
1051 JSScript *
1052 js_NewScript(JSContext *cx, uint32 length, uint32 nsrcnotes, uint32 ntrynotes)
1053 {
1054 JSScript *script;
1056 /* Round up source note count to align script->trynotes for its type. */
1057 if (ntrynotes)
1058 nsrcnotes += JSTRYNOTE_ALIGNMASK;
1059 script = (JSScript *) JS_malloc(cx,
1060 sizeof(JSScript) +
1061 length * sizeof(jsbytecode) +
1062 nsrcnotes * sizeof(jssrcnote) +
1063 ntrynotes * sizeof(JSTryNote));
1064 if (!script)
1065 return NULL;
1066 memset(script, 0, sizeof(JSScript));
1067 script->code = script->main = (jsbytecode *)(script + 1);
1068 script->length = length;
1069 script->version = cx->version;
1070 if (ntrynotes) {
1071 script->trynotes = (JSTryNote *)
1072 ((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
1073 ~(jsword)JSTRYNOTE_ALIGNMASK);
1074 memset(script->trynotes, 0, ntrynotes * sizeof(JSTryNote));
1075 }
1076 return script;
1077 }
1079 JS_FRIEND_API(JSScript *)
1080 js_NewScriptFromCG(JSContext *cx, JSCodeGenerator *cg, JSFunction *fun)
1081 {
1082 uint32 mainLength, prologLength, nsrcnotes, ntrynotes;
1083 JSScript *script;
1084 const char *filename;
1086 mainLength = CG_OFFSET(cg);
1087 prologLength = CG_PROLOG_OFFSET(cg);
1088 CG_COUNT_FINAL_SRCNOTES(cg, nsrcnotes);
1089 CG_COUNT_FINAL_TRYNOTES(cg, ntrynotes);
1090 script = js_NewScript(cx, prologLength + mainLength, nsrcnotes, ntrynotes);
1091 if (!script)
1092 return NULL;
1094 /* Now that we have script, error control flow must go to label bad. */
1095 script->main += prologLength;
1096 memcpy(script->code, CG_PROLOG_BASE(cg), prologLength * sizeof(jsbytecode));
1097 memcpy(script->main, CG_BASE(cg), mainLength * sizeof(jsbytecode));
1098 script->numGlobalVars = cg->treeContext.numGlobalVars;
1099 if (!js_InitAtomMap(cx, &script->atomMap, &cg->atomList))
1100 goto bad;
1102 filename = cg->filename;
1103 if (filename) {
1104 script->filename = js_SaveScriptFilename(cx, filename);
1105 if (!script->filename)
1106 goto bad;
1107 }
1108 script->lineno = cg->firstLine;
1109 script->depth = cg->maxStackDepth;
1110 if (cg->principals) {
1111 script->principals = cg->principals;
1112 JSPRINCIPALS_HOLD(cx, script->principals);
1113 }
1115 if (!js_FinishTakingSrcNotes(cx, cg, SCRIPT_NOTES(script)))
1116 goto bad;
1117 if (script->trynotes)
1118 js_FinishTakingTryNotes(cx, cg, script->trynotes);
1120 /* Tell the debugger about this compiled script. */
1121 js_CallNewScriptHook(cx, script, fun);
1122 return script;
1124 bad:
1125 js_DestroyScript(cx, script);
1126 return NULL;
1127 }
1129 JS_FRIEND_API(void)
1130 js_CallNewScriptHook(JSContext *cx, JSScript *script, JSFunction *fun)
1131 {
1132 JSRuntime *rt;
1133 JSNewScriptHook hook;
1135 rt = cx->runtime;
1136 hook = rt->newScriptHook;
1137 if (hook) {
1138 JS_KEEP_ATOMS(rt);
1139 hook(cx, script->filename, script->lineno, script, fun,
1140 rt->newScriptHookData);
1141 JS_UNKEEP_ATOMS(rt);
1142 }
1143 }
1145 void
1146 js_DestroyScript(JSContext *cx, JSScript *script)
1147 {
1148 JSRuntime *rt;
1149 JSDestroyScriptHook hook;
1151 rt = cx->runtime;
1152 hook = rt->destroyScriptHook;
1153 if (hook)
1154 hook(cx, script, rt->destroyScriptHookData);
1156 JS_ClearScriptTraps(cx, script);
1157 js_FreeAtomMap(cx, &script->atomMap);
1158 if (script->principals)
1159 JSPRINCIPALS_DROP(cx, script->principals);
1160 JS_free(cx, script);
1161 }
1163 void
1164 js_MarkScript(JSContext *cx, JSScript *script, void *arg)
1165 {
1166 JSAtomMap *map;
1167 uintN i, length;
1168 JSAtom **vector;
1170 map = &script->atomMap;
1171 length = map->length;
1172 vector = map->vector;
1173 for (i = 0; i < length; i++)
1174 GC_MARK_ATOM(cx, vector[i], arg);
1176 if (script->filename)
1177 js_MarkScriptFilename(script->filename);
1178 }
1180 jssrcnote *
1181 js_GetSrcNote(JSScript *script, jsbytecode *pc)
1182 {
1183 jssrcnote *sn;
1184 ptrdiff_t offset, target;
1186 target = PTRDIFF(pc, script->code, jsbytecode);
1187 if ((uint32)target >= script->length)
1188 return NULL;
1189 offset = 0;
1190 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1191 offset += SN_DELTA(sn);
1192 if (offset == target && SN_IS_GETTABLE(sn))
1193 return sn;
1194 }
1195 return NULL;
1196 }
1198 uintN
1199 js_PCToLineNumber(JSContext *cx, JSScript *script, jsbytecode *pc)
1200 {
1201 JSAtom *atom;
1202 JSFunction *fun;
1203 uintN lineno;
1204 ptrdiff_t offset, target;
1205 jssrcnote *sn;
1206 JSSrcNoteType type;
1208 /*
1209 * Special case: function definition needs no line number note because
1210 * the function's script contains its starting line number.
1211 */
1212 if (*pc == JSOP_DEFFUN) {
1213 atom = GET_ATOM(cx, script, pc);
1214 fun = (JSFunction *) JS_GetPrivate(cx, ATOM_TO_OBJECT(atom));
1215 JS_ASSERT(fun->interpreted);
1216 return fun->u.script->lineno;
1217 }
1219 /*
1220 * General case: walk through source notes accumulating their deltas,
1221 * keeping track of line-number notes, until we pass the note for pc's
1222 * offset within script->code.
1223 */
1224 lineno = script->lineno;
1225 offset = 0;
1226 target = PTRDIFF(pc, script->code, jsbytecode);
1227 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1228 offset += SN_DELTA(sn);
1229 type = (JSSrcNoteType) SN_TYPE(sn);
1230 if (type == SRC_SETLINE) {
1231 if (offset <= target)
1232 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1233 } else if (type == SRC_NEWLINE) {
1234 if (offset <= target)
1235 lineno++;
1236 }
1237 if (offset > target)
1238 break;
1239 }
1240 return lineno;
1241 }
1243 jsbytecode *
1244 js_LineNumberToPC(JSScript *script, uintN target)
1245 {
1246 ptrdiff_t offset;
1247 uintN lineno;
1248 jssrcnote *sn;
1249 JSSrcNoteType type;
1251 offset = 0;
1252 lineno = script->lineno;
1253 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1254 if (lineno >= target)
1255 break;
1256 offset += SN_DELTA(sn);
1257 type = (JSSrcNoteType) SN_TYPE(sn);
1258 if (type == SRC_SETLINE) {
1259 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1260 } else if (type == SRC_NEWLINE) {
1261 lineno++;
1262 }
1263 }
1264 return script->code + offset;
1265 }
1267 uintN
1268 js_GetScriptLineExtent(JSScript *script)
1269 {
1270 uintN lineno;
1271 jssrcnote *sn;
1272 JSSrcNoteType type;
1274 lineno = script->lineno;
1275 for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
1276 type = (JSSrcNoteType) SN_TYPE(sn);
1277 if (type == SRC_SETLINE) {
1278 lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
1279 } else if (type == SRC_NEWLINE) {
1280 lineno++;
1281 }
1282 }
1283 return 1 + lineno - script->lineno;
1284 }