RetroZilla/js/src/jsscript.c
2015-10-20 23:03:22 -04:00

1712 lines
50 KiB
C

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=78:
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code, released
* March 31, 1998.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* JS script operations.
*/
#include "jsstddef.h"
#include <string.h>
#include "jstypes.h"
#include "jsutil.h" /* Added by JSIFY */
#include "jsprf.h"
#include "jsapi.h"
#include "jsatom.h"
#include "jscntxt.h"
#include "jsconfig.h"
#include "jsdbgapi.h"
#include "jsemit.h"
#include "jsfun.h"
#include "jsinterp.h"
#include "jslock.h"
#include "jsnum.h"
#include "jsopcode.h"
#include "jsscript.h"
#if JS_HAS_XDR
#include "jsxdrapi.h"
#endif
#if JS_HAS_SCRIPT_OBJECT
static const char js_script_exec[] = "Script.prototype.exec";
static const char js_script_compile[] = "Script.prototype.compile";
/*
* This routine requires that obj has been locked previously.
*/
static jsint
GetScriptExecDepth(JSContext *cx, JSObject *obj)
{
jsval v;
JS_ASSERT(JS_IS_OBJ_LOCKED(cx, obj));
v = LOCKED_OBJ_GET_SLOT(obj, JSSLOT_START(&js_ScriptClass));
return JSVAL_TO_INT(v);
}
static void
AdjustScriptExecDepth(JSContext *cx, JSObject *obj, jsint delta)
{
jsint execDepth;
JS_LOCK_OBJ(cx, obj);
execDepth = GetScriptExecDepth(cx, obj);
LOCKED_OBJ_SET_SLOT(obj, JSSLOT_START(&js_ScriptClass),
INT_TO_JSVAL(execDepth + delta));
JS_UNLOCK_OBJ(cx, obj);
}
#if JS_HAS_TOSOURCE
static JSBool
script_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
uint32 indent;
JSScript *script;
size_t i, j, k, n;
char buf[16];
jschar *s, *t;
JSString *str;
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
indent = 0;
if (argc && !js_ValueToECMAUint32(cx, argv[0], &indent))
return JS_FALSE;
script = (JSScript *) JS_GetPrivate(cx, obj);
/* Let n count the source string length, j the "front porch" length. */
j = JS_snprintf(buf, sizeof buf, "(new %s(", js_ScriptClass.name);
n = j + 2;
if (!script) {
/* Let k count the constructor argument string length. */
k = 0;
s = NULL; /* quell GCC overwarning */
} else {
str = JS_DecompileScript(cx, script, "Script.prototype.toSource",
(uintN)indent);
if (!str)
return JS_FALSE;
str = js_QuoteString(cx, str, '\'');
if (!str)
return JS_FALSE;
s = JSSTRING_CHARS(str);
k = JSSTRING_LENGTH(str);
n += k;
}
/* Allocate the source string and copy into it. */
t = (jschar *) JS_malloc(cx, (n + 1) * sizeof(jschar));
if (!t)
return JS_FALSE;
for (i = 0; i < j; i++)
t[i] = buf[i];
for (j = 0; j < k; i++, j++)
t[i] = s[j];
t[i++] = ')';
t[i++] = ')';
t[i] = 0;
/* Create and return a JS string for t. */
str = JS_NewUCString(cx, t, n);
if (!str) {
JS_free(cx, t);
return JS_FALSE;
}
*rval = STRING_TO_JSVAL(str);
return JS_TRUE;
}
#endif /* JS_HAS_TOSOURCE */
static JSBool
script_toString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
uint32 indent;
JSScript *script;
JSString *str;
indent = 0;
if (argc && !js_ValueToECMAUint32(cx, argv[0], &indent))
return JS_FALSE;
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
script = (JSScript *) JS_GetPrivate(cx, obj);
if (!script) {
*rval = STRING_TO_JSVAL(cx->runtime->emptyString);
return JS_TRUE;
}
str = JS_DecompileScript(cx, script, "Script.prototype.toString",
(uintN)indent);
if (!str)
return JS_FALSE;
*rval = STRING_TO_JSVAL(str);
return JS_TRUE;
}
static JSBool
script_compile(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
JSString *str;
JSObject *scopeobj;
jsval v;
JSScript *script, *oldscript;
JSStackFrame *fp, *caller;
const char *file;
uintN line;
JSPrincipals *principals;
jsint execDepth;
/* Make sure obj is a Script object. */
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
/* If no args, leave private undefined and return early. */
if (argc == 0)
goto out;
/* Otherwise, the first arg is the script source to compile. */
str = js_ValueToString(cx, argv[0]);
if (!str)
return JS_FALSE;
argv[0] = STRING_TO_JSVAL(str);
scopeobj = NULL;
if (argc >= 2) {
if (!js_ValueToObject(cx, argv[1], &scopeobj))
return JS_FALSE;
argv[1] = OBJECT_TO_JSVAL(scopeobj);
}
/* Compile using the caller's scope chain, which js_Invoke passes to fp. */
fp = cx->fp;
caller = JS_GetScriptedCaller(cx, fp);
JS_ASSERT(!caller || fp->scopeChain == caller->scopeChain);
if (caller) {
if (!scopeobj) {
scopeobj = js_GetScopeChain(cx, caller);
if (!scopeobj)
return JS_FALSE;
fp->scopeChain = scopeobj; /* for the compiler's benefit */
}
principals = JS_EvalFramePrincipals(cx, fp, caller);
file = js_ComputeFilename(cx, caller, principals, &line);
} else {
file = NULL;
line = 0;
principals = NULL;
}
/* Ensure we compile this script with the right (inner) principals. */
scopeobj = js_CheckScopeChainValidity(cx, scopeobj, js_script_compile);
if (!scopeobj)
return JS_FALSE;
/*
* Compile the new script using the caller's scope chain, a la eval().
* Unlike jsobj.c:obj_eval, however, we do not set JSFRAME_EVAL in fp's
* flags, because compilation is here separated from execution, and the
* run-time scope chain may not match the compile-time. JSFRAME_EVAL is
* tested in jsemit.c and jsscan.c to optimize based on identity of run-
* and compile-time scope.
*/
fp->flags |= JSFRAME_SCRIPT_OBJECT;
script = JS_CompileUCScriptForPrincipals(cx, scopeobj, principals,
JSSTRING_CHARS(str),
JSSTRING_LENGTH(str),
file, line);
if (!script)
return JS_FALSE;
JS_LOCK_OBJ(cx, obj);
execDepth = GetScriptExecDepth(cx, obj);
/*
* execDepth must be 0 to allow compilation here, otherwise the JSScript
* struct can be released while running.
*/
if (execDepth > 0) {
JS_UNLOCK_OBJ(cx, obj);
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_COMPILE_EXECED_SCRIPT);
return JS_FALSE;
}
/* Swap script for obj's old script, if any. */
v = LOCKED_OBJ_GET_SLOT(obj, JSSLOT_PRIVATE);
oldscript = !JSVAL_IS_VOID(v) ? (JSScript *) JSVAL_TO_PRIVATE(v) : NULL;
LOCKED_OBJ_SET_SLOT(obj, JSSLOT_PRIVATE, PRIVATE_TO_JSVAL(script));
JS_UNLOCK_OBJ(cx, obj);
if (oldscript)
js_DestroyScript(cx, oldscript);
script->object = obj;
js_CallNewScriptHook(cx, script, NULL);
out:
/* Return the object. */
*rval = OBJECT_TO_JSVAL(obj);
return JS_TRUE;
}
static JSBool
script_exec(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
JSObject *scopeobj, *parent;
JSStackFrame *fp, *caller;
JSScript *script;
JSBool ok;
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
scopeobj = NULL;
if (argc) {
if (!js_ValueToObject(cx, argv[0], &scopeobj))
return JS_FALSE;
argv[0] = OBJECT_TO_JSVAL(scopeobj);
}
/*
* Emulate eval() by using caller's this, var object, sharp array, etc.,
* all propagated by js_Execute via a non-null fourth (down) argument to
* js_Execute. If there is no scripted caller, js_Execute uses its second
* (chain) argument to set the exec frame's varobj, thisp, and scopeChain.
*
* Unlike eval, which the compiler detects, Script.prototype.exec may be
* called from a lightweight function, or even from native code (in which
* case fp->varobj and fp->scopeChain are null). If exec is called from
* a lightweight function, we will need to get a Call object representing
* its frame, to act as the var object and scope chain head.
*/
fp = cx->fp;
caller = JS_GetScriptedCaller(cx, fp);
if (caller && !caller->varobj) {
/* Called from a lightweight function. */
JS_ASSERT(caller->fun && !JSFUN_HEAVYWEIGHT_TEST(caller->fun->flags));
/* Scope chain links from Call object to callee's parent. */
parent = OBJ_GET_PARENT(cx, JSVAL_TO_OBJECT(caller->argv[-2]));
if (!js_GetCallObject(cx, caller, parent))
return JS_FALSE;
}
if (!scopeobj) {
/* No scope object passed in: try to use the caller's scope chain. */
if (caller) {
/*
* Load caller->scopeChain after the conditional js_GetCallObject
* call above, which resets scopeChain as well as varobj.
*/
scopeobj = js_GetScopeChain(cx, caller);
if (!scopeobj)
return JS_FALSE;
} else {
/*
* Called from native code, so we don't know what scope object to
* use. We could use parent (see above), but Script.prototype.exec
* might be a shared/sealed "superglobal" method. A more general
* approach would use cx->globalObject, which will be the same as
* exec.__parent__ in the non-superglobal case. In the superglobal
* case it's the right object: the global, not the superglobal.
*/
scopeobj = cx->globalObject;
}
}
scopeobj = js_CheckScopeChainValidity(cx, scopeobj, js_script_exec);
if (!scopeobj)
return JS_FALSE;
/* Keep track of nesting depth for the script. */
AdjustScriptExecDepth(cx, obj, 1);
/* Must get to out label after this */
script = (JSScript *) JS_GetPrivate(cx, obj);
if (!script) {
ok = JS_FALSE;
goto out;
}
/* Belt-and-braces: check that this script object has access to scopeobj. */
ok = js_CheckPrincipalsAccess(cx, scopeobj, script->principals,
CLASS_ATOM(cx, Script));
if (!ok)
goto out;
ok = js_Execute(cx, scopeobj, script, caller, JSFRAME_EVAL, rval);
out:
AdjustScriptExecDepth(cx, obj, -1);
return ok;
}
#if JS_HAS_XDR
static JSBool
XDRAtomMap(JSXDRState *xdr, JSAtomMap *map)
{
JSContext *cx;
uint32 natoms, i, index;
JSAtom **atoms;
cx = xdr->cx;
if (xdr->mode == JSXDR_ENCODE)
natoms = (uint32)map->length;
if (!JS_XDRUint32(xdr, &natoms))
return JS_FALSE;
if (xdr->mode == JSXDR_ENCODE) {
atoms = map->vector;
} else {
if (natoms == 0) {
atoms = NULL;
} else {
atoms = (JSAtom **) JS_malloc(cx, (size_t)natoms * sizeof *atoms);
if (!atoms)
return JS_FALSE;
#ifdef DEBUG
memset(atoms, 0, (size_t)natoms * sizeof *atoms);
#endif
}
map->vector = atoms;
map->length = natoms;
}
for (i = 0; i != natoms; ++i) {
if (xdr->mode == JSXDR_ENCODE)
index = i;
if (!JS_XDRUint32(xdr, &index))
goto bad;
/*
* Assert that, when decoding, the read index is valid and points to
* an unoccupied element of atoms array.
*/
JS_ASSERT(index < natoms);
JS_ASSERT(xdr->mode == JSXDR_ENCODE || !atoms[index]);
if (!js_XDRAtom(xdr, &atoms[index]))
goto bad;
}
return JS_TRUE;
bad:
if (xdr->mode == JSXDR_DECODE) {
JS_free(cx, atoms);
map->vector = NULL;
map->length = 0;
}
return JS_FALSE;
}
JSBool
js_XDRScript(JSXDRState *xdr, JSScript **scriptp, JSBool *hasMagic)
{
JSContext *cx;
JSScript *script, *newscript, *oldscript;
uint32 length, lineno, depth, magic, nsrcnotes, ntrynotes;
uint32 prologLength, version;
JSBool filenameWasSaved;
jssrcnote *notes, *sn;
cx = xdr->cx;
script = *scriptp;
nsrcnotes = ntrynotes = 0;
filenameWasSaved = JS_FALSE;
notes = NULL;
/*
* Encode prologLength and version after script->length (_2 or greater),
* but decode both new (>= _2) and old, prolog&version-free (_1) scripts.
* Version _3 supports principals serialization. Version _4 reorders the
* nsrcnotes and ntrynotes fields to come before everything except magic,
* length, prologLength, and version, so that srcnote and trynote storage
* can be allocated as part of the JSScript (along with bytecode storage).
*
* So far, the magic number has not changed for every jsopcode.tbl change.
* We stipulate forward compatibility by requiring old bytecodes never to
* change or go away (modulo a few exceptions before the XDR interfaces
* evolved, and a few exceptions during active trunk development). With
* the addition of JSOP_STOP to support JS_THREADED_INTERP, we make a new
* magic number (_5) so that we know to append JSOP_STOP to old scripts
* when deserializing.
*/
if (xdr->mode == JSXDR_ENCODE)
magic = JSXDR_MAGIC_SCRIPT_CURRENT;
if (!JS_XDRUint32(xdr, &magic))
return JS_FALSE;
JS_ASSERT((uint32)JSXDR_MAGIC_SCRIPT_5 - (uint32)JSXDR_MAGIC_SCRIPT_1 == 4);
if (magic - (uint32)JSXDR_MAGIC_SCRIPT_1 > 4) {
if (!hasMagic) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_BAD_SCRIPT_MAGIC);
return JS_FALSE;
}
*hasMagic = JS_FALSE;
return JS_TRUE;
}
if (hasMagic)
*hasMagic = JS_TRUE;
if (xdr->mode == JSXDR_ENCODE) {
length = script->length;
prologLength = PTRDIFF(script->main, script->code, jsbytecode);
JS_ASSERT((int16)script->version != JSVERSION_UNKNOWN);
version = (uint32)script->version | (script->numGlobalVars << 16);
lineno = (uint32)script->lineno;
depth = (uint32)script->depth;
/* Count the srcnotes, keeping notes pointing at the first one. */
notes = SCRIPT_NOTES(script);
for (sn = notes; !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn))
continue;
nsrcnotes = PTRDIFF(sn, notes, jssrcnote);
nsrcnotes++; /* room for the terminator */
/* Count the trynotes. */
if (script->trynotes) {
while (script->trynotes[ntrynotes].catchStart)
ntrynotes++;
ntrynotes++; /* room for the end marker */
}
}
if (!JS_XDRUint32(xdr, &length))
return JS_FALSE;
if (magic >= JSXDR_MAGIC_SCRIPT_2) {
if (!JS_XDRUint32(xdr, &prologLength))
return JS_FALSE;
if (!JS_XDRUint32(xdr, &version))
return JS_FALSE;
/* To fuse allocations, we need srcnote and trynote counts early. */
if (magic >= JSXDR_MAGIC_SCRIPT_4) {
if (!JS_XDRUint32(xdr, &nsrcnotes))
return JS_FALSE;
if (!JS_XDRUint32(xdr, &ntrynotes))
return JS_FALSE;
}
}
if (xdr->mode == JSXDR_DECODE) {
size_t alloclength = length;
if (magic < JSXDR_MAGIC_SCRIPT_5)
++alloclength; /* add a byte for JSOP_STOP */
script = js_NewScript(cx, alloclength, nsrcnotes, ntrynotes);
if (!script)
return JS_FALSE;
if (magic >= JSXDR_MAGIC_SCRIPT_2) {
script->main += prologLength;
script->version = (JSVersion) (version & 0xffff);
script->numGlobalVars = (uint16) (version >> 16);
/* If we know nsrcnotes, we allocated space for notes in script. */
if (magic >= JSXDR_MAGIC_SCRIPT_4)
notes = SCRIPT_NOTES(script);
}
*scriptp = script;
}
/*
* Control hereafter must goto error on failure, in order for the DECODE
* case to destroy script and conditionally free notes, which if non-null
* in the (DECODE and magic < _4) case must point at a temporary vector
* allocated just below.
*/
oldscript = xdr->script;
xdr->script = script;
if (!JS_XDRBytes(xdr, (char *)script->code, length * sizeof(jsbytecode)) ||
!XDRAtomMap(xdr, &script->atomMap)) {
goto error;
}
if (magic < JSXDR_MAGIC_SCRIPT_5) {
if (xdr->mode == JSXDR_DECODE) {
/*
* Append JSOP_STOP to old scripts, to relieve the interpreter
* from having to bounds-check pc. Also take care to increment
* length, as it is used below and must count all bytecode.
*/
script->code[length++] = JSOP_STOP;
}
if (magic < JSXDR_MAGIC_SCRIPT_4) {
if (!JS_XDRUint32(xdr, &nsrcnotes))
goto error;
if (xdr->mode == JSXDR_DECODE) {
notes = (jssrcnote *)
JS_malloc(cx, nsrcnotes * sizeof(jssrcnote));
if (!notes)
goto error;
}
}
}
if (!JS_XDRBytes(xdr, (char *)notes, nsrcnotes * sizeof(jssrcnote)) ||
!JS_XDRCStringOrNull(xdr, (char **)&script->filename) ||
!JS_XDRUint32(xdr, &lineno) ||
!JS_XDRUint32(xdr, &depth) ||
(magic < JSXDR_MAGIC_SCRIPT_4 && !JS_XDRUint32(xdr, &ntrynotes))) {
goto error;
}
/* Script principals transcoding support comes with versions >= _3. */
if (magic >= JSXDR_MAGIC_SCRIPT_3) {
JSPrincipals *principals;
uint32 encodeable;
if (xdr->mode == JSXDR_ENCODE) {
principals = script->principals;
encodeable = (cx->runtime->principalsTranscoder != NULL);
if (!JS_XDRUint32(xdr, &encodeable))
goto error;
if (encodeable &&
!cx->runtime->principalsTranscoder(xdr, &principals)) {
goto error;
}
} else {
if (!JS_XDRUint32(xdr, &encodeable))
goto error;
if (encodeable) {
if (!cx->runtime->principalsTranscoder) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_CANT_DECODE_PRINCIPALS);
goto error;
}
if (!cx->runtime->principalsTranscoder(xdr, &principals))
goto error;
script->principals = principals;
}
}
}
if (xdr->mode == JSXDR_DECODE) {
const char *filename = script->filename;
if (filename) {
filename = js_SaveScriptFilename(cx, filename);
if (!filename)
goto error;
JS_free(cx, (void *) script->filename);
script->filename = filename;
filenameWasSaved = JS_TRUE;
}
script->lineno = (uintN)lineno;
script->depth = (uintN)depth;
if (magic < JSXDR_MAGIC_SCRIPT_4) {
/*
* Argh, we have to reallocate script, copy notes into the extra
* space after the bytecodes, and free the temporary notes vector.
* First, add enough slop to nsrcnotes so we can align the address
* after the srcnotes of the first trynote.
*/
uint32 osrcnotes = nsrcnotes;
if (ntrynotes)
nsrcnotes += JSTRYNOTE_ALIGNMASK;
newscript = (JSScript *) JS_realloc(cx, script,
sizeof(JSScript) +
length * sizeof(jsbytecode) +
nsrcnotes * sizeof(jssrcnote) +
ntrynotes * sizeof(JSTryNote));
if (!newscript)
goto error;
*scriptp = script = newscript;
script->code = (jsbytecode *)(script + 1);
script->main = script->code + prologLength;
memcpy(script->code + length, notes, osrcnotes * sizeof(jssrcnote));
JS_free(cx, (void *) notes);
notes = NULL;
if (ntrynotes) {
script->trynotes = (JSTryNote *)
((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
~(jsword)JSTRYNOTE_ALIGNMASK);
memset(script->trynotes, 0, ntrynotes * sizeof(JSTryNote));
}
}
}
while (ntrynotes) {
JSTryNote *tn = &script->trynotes[--ntrynotes];
uint32 start = (uint32) tn->start,
catchLength = (uint32) tn->length,
catchStart = (uint32) tn->catchStart;
if (!JS_XDRUint32(xdr, &start) ||
!JS_XDRUint32(xdr, &catchLength) ||
!JS_XDRUint32(xdr, &catchStart)) {
goto error;
}
tn->start = (ptrdiff_t) start;
tn->length = (ptrdiff_t) catchLength;
tn->catchStart = (ptrdiff_t) catchStart;
}
xdr->script = oldscript;
return JS_TRUE;
error:
if (xdr->mode == JSXDR_DECODE) {
if (script->filename && !filenameWasSaved) {
JS_free(cx, (void *) script->filename);
script->filename = NULL;
}
if (notes && magic < JSXDR_MAGIC_SCRIPT_4)
JS_free(cx, (void *) notes);
js_DestroyScript(cx, script);
*scriptp = NULL;
}
return JS_FALSE;
}
#if JS_HAS_XDR_FREEZE_THAW
/*
* These cannot be exposed to web content, and chrome does not need them, so
* we take them out of the Mozilla client altogether. Fortunately, there is
* no way to serialize a native function (see fun_xdrObject in jsfun.c).
*/
static JSBool
script_freeze(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
JSXDRState *xdr;
JSScript *script;
JSBool ok, hasMagic;
uint32 len;
void *buf;
JSString *str;
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
script = (JSScript *) JS_GetPrivate(cx, obj);
if (!script)
return JS_TRUE;
/* create new XDR */
xdr = JS_XDRNewMem(cx, JSXDR_ENCODE);
if (!xdr)
return JS_FALSE;
/* write */
ok = js_XDRScript(xdr, &script, &hasMagic);
if (!ok)
goto out;
if (!hasMagic) {
*rval = JSVAL_VOID;
goto out;
}
buf = JS_XDRMemGetData(xdr, &len);
if (!buf) {
ok = JS_FALSE;
goto out;
}
JS_ASSERT((jsword)buf % sizeof(jschar) == 0);
len /= sizeof(jschar);
str = JS_NewUCStringCopyN(cx, (jschar *)buf, len);
if (!str) {
ok = JS_FALSE;
goto out;
}
#if IS_BIG_ENDIAN
{
jschar *chars;
uint32 i;
/* Swap bytes in Unichars to keep frozen strings machine-independent. */
chars = JS_GetStringChars(str);
for (i = 0; i < len; i++)
chars[i] = JSXDR_SWAB16(chars[i]);
}
#endif
*rval = STRING_TO_JSVAL(str);
out:
JS_XDRDestroy(xdr);
return ok;
}
static JSBool
script_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
JSXDRState *xdr;
JSString *str;
void *buf;
uint32 len;
jsval v;
JSScript *script, *oldscript;
JSBool ok, hasMagic;
if (!JS_InstanceOf(cx, obj, &js_ScriptClass, argv))
return JS_FALSE;
if (argc == 0)
return JS_TRUE;
str = js_ValueToString(cx, argv[0]);
if (!str)
return JS_FALSE;
argv[0] = STRING_TO_JSVAL(str);
/* create new XDR */
xdr = JS_XDRNewMem(cx, JSXDR_DECODE);
if (!xdr)
return JS_FALSE;
buf = JS_GetStringChars(str);
len = JS_GetStringLength(str);
#if IS_BIG_ENDIAN
{
jschar *from, *to;
uint32 i;
/* Swap bytes in Unichars to keep frozen strings machine-independent. */
from = (jschar *)buf;
to = (jschar *) JS_malloc(cx, len * sizeof(jschar));
if (!to) {
JS_XDRDestroy(xdr);
return JS_FALSE;
}
for (i = 0; i < len; i++)
to[i] = JSXDR_SWAB16(from[i]);
buf = (char *)to;
}
#endif
len *= sizeof(jschar);
JS_XDRMemSetData(xdr, buf, len);
/* XXXbe should magic mismatch be error, or false return value? */
ok = js_XDRScript(xdr, &script, &hasMagic);
if (!ok)
goto out;
if (!hasMagic) {
*rval = JSVAL_FALSE;
goto out;
}
JS_LOCK_OBJ(cx, obj);
execDepth = GetScriptExecDepth(cx, obj);
/*
* execDepth must be 0 to allow compilation here, otherwise the JSScript
* struct can be released while running.
*/
if (execDepth > 0) {
JS_UNLOCK_OBJ(cx, obj);
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_COMPILE_EXECED_SCRIPT);
goto out;
}
/* Swap script for obj's old script, if any. */
v = LOCKED_OBJ_GET_SLOT(cx, obj, JSSLOT_PRIVATE);
oldscript = !JSVAL_IS_VOID(v) ? (JSScript *) JSVAL_TO_PRIVATE(v) : NULL;
LOCKED_OBJ_SET_SLOT(cx, obj, JSSLOT_PRIVATE, PRIVATE_TO_JSVAL(script));
JS_UNLOCK_OBJ(cx, obj);
if (oldscript)
js_DestroyScript(cx, oldscript);
script->object = obj;
js_CallNewScriptHook(cx, script, NULL);
out:
/*
* We reset the buffer to be NULL so that it doesn't free the chars
* memory owned by str (argv[0]).
*/
JS_XDRMemSetData(xdr, NULL, 0);
JS_XDRDestroy(xdr);
#if IS_BIG_ENDIAN
JS_free(cx, buf);
#endif
*rval = JSVAL_TRUE;
return ok;
}
static const char js_thaw_str[] = "thaw";
#endif /* JS_HAS_XDR_FREEZE_THAW */
#endif /* JS_HAS_XDR */
static JSFunctionSpec script_methods[] = {
#if JS_HAS_TOSOURCE
{js_toSource_str, script_toSource, 0,0,0},
#endif
{js_toString_str, script_toString, 0,0,0},
{"compile", script_compile, 2,0,0},
{"exec", script_exec, 1,0,0},
#if JS_HAS_XDR_FREEZE_THAW
{"freeze", script_freeze, 0,0,0},
{js_thaw_str, script_thaw, 1,0,0},
#endif /* JS_HAS_XDR_FREEZE_THAW */
{0,0,0,0,0}
};
#endif /* JS_HAS_SCRIPT_OBJECT */
static void
script_finalize(JSContext *cx, JSObject *obj)
{
JSScript *script;
script = (JSScript *) JS_GetPrivate(cx, obj);
if (script)
js_DestroyScript(cx, script);
}
static JSBool
script_call(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
#if JS_HAS_SCRIPT_OBJECT
return script_exec(cx, JSVAL_TO_OBJECT(argv[-2]), argc, argv, rval);
#else
return JS_FALSE;
#endif
}
static uint32
script_mark(JSContext *cx, JSObject *obj, void *arg)
{
JSScript *script;
script = (JSScript *) JS_GetPrivate(cx, obj);
if (script)
js_MarkScript(cx, script);
return 0;
}
#if !JS_HAS_SCRIPT_OBJECT
const char js_Script_str[] = "Script";
#define JSProto_Script JSProto_Object
#endif
JS_FRIEND_DATA(JSClass) js_ScriptClass = {
js_Script_str,
JSCLASS_HAS_PRIVATE | JSCLASS_HAS_CACHED_PROTO(JSProto_Script) |
JSCLASS_HAS_RESERVED_SLOTS(1),
JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, script_finalize,
NULL, NULL, script_call, NULL,/*XXXbe xdr*/
NULL, NULL, script_mark, 0
};
#if JS_HAS_SCRIPT_OBJECT
static JSBool
Script(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
/* If not constructing, replace obj with a new Script object. */
if (!(cx->fp->flags & JSFRAME_CONSTRUCTING)) {
obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
if (!obj)
return JS_FALSE;
/*
* script_compile does not use rval to root its temporaries
* so we can use it to root obj.
*/
*rval = OBJECT_TO_JSVAL(obj);
}
if (!JS_SetReservedSlot(cx, obj, 0, INT_TO_JSVAL(0)))
return JS_FALSE;
return script_compile(cx, obj, argc, argv, rval);
}
#if JS_HAS_XDR_FREEZE_THAW
static JSBool
script_static_thaw(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
obj = js_NewObject(cx, &js_ScriptClass, NULL, NULL);
if (!obj)
return JS_FALSE;
if (!script_thaw(cx, obj, argc, argv, rval))
return JS_FALSE;
*rval = OBJECT_TO_JSVAL(obj);
return JS_TRUE;
}
static JSFunctionSpec script_static_methods[] = {
{js_thaw_str, script_static_thaw, 1,0,0},
{0,0,0,0,0}
};
#else /* !JS_HAS_XDR_FREEZE_THAW */
#define script_static_methods NULL
#endif /* !JS_HAS_XDR_FREEZE_THAW */
JSObject *
js_InitScriptClass(JSContext *cx, JSObject *obj)
{
return JS_InitClass(cx, obj, NULL, &js_ScriptClass, Script, 1,
NULL, script_methods, NULL, script_static_methods);
}
#endif /* JS_HAS_SCRIPT_OBJECT */
/*
* Shared script filename management.
*/
JS_STATIC_DLL_CALLBACK(int)
js_compare_strings(const void *k1, const void *k2)
{
return strcmp(k1, k2) == 0;
}
/* Shared with jsatom.c to save code space. */
extern void * JS_DLL_CALLBACK
js_alloc_table_space(void *priv, size_t size);
extern void JS_DLL_CALLBACK
js_free_table_space(void *priv, void *item);
/* NB: This struct overlays JSHashEntry -- see jshash.h, do not reorganize. */
typedef struct ScriptFilenameEntry {
JSHashEntry *next; /* hash chain linkage */
JSHashNumber keyHash; /* key hash function result */
const void *key; /* ptr to filename, below */
uint32 flags; /* user-defined filename prefix flags */
JSPackedBool mark; /* GC mark flag */
char filename[3]; /* two or more bytes, NUL-terminated */
} ScriptFilenameEntry;
JS_STATIC_DLL_CALLBACK(JSHashEntry *)
js_alloc_sftbl_entry(void *priv, const void *key)
{
size_t nbytes = offsetof(ScriptFilenameEntry, filename) + strlen(key) + 1;
return (JSHashEntry *) malloc(JS_MAX(nbytes, sizeof(JSHashEntry)));
}
JS_STATIC_DLL_CALLBACK(void)
js_free_sftbl_entry(void *priv, JSHashEntry *he, uintN flag)
{
if (flag != HT_FREE_ENTRY)
return;
free(he);
}
static JSHashAllocOps sftbl_alloc_ops = {
js_alloc_table_space, js_free_table_space,
js_alloc_sftbl_entry, js_free_sftbl_entry
};
JSBool
js_InitRuntimeScriptState(JSRuntime *rt)
{
#ifdef JS_THREADSAFE
JS_ASSERT(!rt->scriptFilenameTableLock);
rt->scriptFilenameTableLock = JS_NEW_LOCK();
if (!rt->scriptFilenameTableLock)
return JS_FALSE;
#endif
JS_ASSERT(!rt->scriptFilenameTable);
rt->scriptFilenameTable =
JS_NewHashTable(16, JS_HashString, js_compare_strings, NULL,
&sftbl_alloc_ops, NULL);
if (!rt->scriptFilenameTable) {
js_FinishRuntimeScriptState(rt); /* free lock if threadsafe */
return JS_FALSE;
}
JS_INIT_CLIST(&rt->scriptFilenamePrefixes);
return JS_TRUE;
}
typedef struct ScriptFilenamePrefix {
JSCList links; /* circular list linkage for easy deletion */
const char *name; /* pointer to pinned ScriptFilenameEntry string */
size_t length; /* prefix string length, precomputed */
uint32 flags; /* user-defined flags to inherit from this prefix */
} ScriptFilenamePrefix;
void
js_FinishRuntimeScriptState(JSRuntime *rt)
{
if (rt->scriptFilenameTable) {
JS_HashTableDestroy(rt->scriptFilenameTable);
rt->scriptFilenameTable = NULL;
}
#ifdef JS_THREADSAFE
if (rt->scriptFilenameTableLock) {
JS_DESTROY_LOCK(rt->scriptFilenameTableLock);
rt->scriptFilenameTableLock = NULL;
}
#endif
}
void
js_FreeRuntimeScriptState(JSRuntime *rt)
{
ScriptFilenamePrefix *sfp;
if (!rt->scriptFilenameTable)
return;
while (!JS_CLIST_IS_EMPTY(&rt->scriptFilenamePrefixes)) {
sfp = (ScriptFilenamePrefix *) rt->scriptFilenamePrefixes.next;
JS_REMOVE_LINK(&sfp->links);
free(sfp);
}
js_FinishRuntimeScriptState(rt);
}
#ifdef DEBUG_brendan
#define DEBUG_SFTBL
#endif
#ifdef DEBUG_SFTBL
size_t sftbl_savings = 0;
#endif
static ScriptFilenameEntry *
SaveScriptFilename(JSRuntime *rt, const char *filename, uint32 flags)
{
JSHashTable *table;
JSHashNumber hash;
JSHashEntry **hep;
ScriptFilenameEntry *sfe;
size_t length;
JSCList *head, *link;
ScriptFilenamePrefix *sfp;
table = rt->scriptFilenameTable;
hash = JS_HashString(filename);
hep = JS_HashTableRawLookup(table, hash, filename);
sfe = (ScriptFilenameEntry *) *hep;
#ifdef DEBUG_SFTBL
if (sfe)
sftbl_savings += strlen(sfe->filename);
#endif
if (!sfe) {
sfe = (ScriptFilenameEntry *)
JS_HashTableRawAdd(table, hep, hash, filename, NULL);
if (!sfe)
return NULL;
sfe->key = strcpy(sfe->filename, filename);
sfe->flags = 0;
sfe->mark = JS_FALSE;
}
/* If saving a prefix, add it to the set in rt->scriptFilenamePrefixes. */
if (flags != 0) {
/* Search in case filename was saved already; we must be idempotent. */
sfp = NULL;
length = strlen(filename);
for (head = link = &rt->scriptFilenamePrefixes;
link->next != head;
link = link->next) {
/* Lag link behind sfp to insert in non-increasing length order. */
sfp = (ScriptFilenamePrefix *) link->next;
if (!strcmp(sfp->name, filename))
break;
if (sfp->length <= length) {
sfp = NULL;
break;
}
sfp = NULL;
}
if (!sfp) {
/* No such prefix: add one now. */
sfp = (ScriptFilenamePrefix *) malloc(sizeof(ScriptFilenamePrefix));
if (!sfp)
return NULL;
JS_INSERT_AFTER(&sfp->links, link);
sfp->name = sfe->filename;
sfp->length = length;
sfp->flags = 0;
}
/*
* Accumulate flags in both sfe and sfp: sfe for later access from the
* JS_GetScriptedCallerFilenameFlags debug-API, and sfp so that longer
* filename entries can inherit by prefix.
*/
sfe->flags |= flags;
sfp->flags |= flags;
}
return sfe;
}
const char *
js_SaveScriptFilename(JSContext *cx, const char *filename)
{
JSRuntime *rt;
ScriptFilenameEntry *sfe;
JSCList *head, *link;
ScriptFilenamePrefix *sfp;
rt = cx->runtime;
JS_ACQUIRE_LOCK(rt->scriptFilenameTableLock);
sfe = SaveScriptFilename(rt, filename, 0);
if (!sfe) {
JS_RELEASE_LOCK(rt->scriptFilenameTableLock);
JS_ReportOutOfMemory(cx);
return NULL;
}
/*
* Try to inherit flags by prefix. We assume there won't be more than a
* few (dozen! ;-) prefixes, so linear search is tolerable.
* XXXbe every time I've assumed that in the JS engine, I've been wrong!
*/
for (head = &rt->scriptFilenamePrefixes, link = head->next;
link != head;
link = link->next) {
sfp = (ScriptFilenamePrefix *) link;
if (!strncmp(sfp->name, filename, sfp->length)) {
sfe->flags |= sfp->flags;
break;
}
}
JS_RELEASE_LOCK(rt->scriptFilenameTableLock);
return sfe->filename;
}
const char *
js_SaveScriptFilenameRT(JSRuntime *rt, const char *filename, uint32 flags)
{
ScriptFilenameEntry *sfe;
/* This may be called very early, via the jsdbgapi.h entry point. */
if (!rt->scriptFilenameTable && !js_InitRuntimeScriptState(rt))
return NULL;
JS_ACQUIRE_LOCK(rt->scriptFilenameTableLock);
sfe = SaveScriptFilename(rt, filename, flags);
JS_RELEASE_LOCK(rt->scriptFilenameTableLock);
if (!sfe)
return NULL;
return sfe->filename;
}
/*
* Back up from a saved filename by its offset within its hash table entry.
*/
#define FILENAME_TO_SFE(fn) \
((ScriptFilenameEntry *) ((fn) - offsetof(ScriptFilenameEntry, filename)))
/*
* The sfe->key member, redundant given sfe->filename but required by the old
* jshash.c code, here gives us a useful sanity check. This assertion will
* very likely botch if someone tries to mark a string that wasn't allocated
* as an sfe->filename.
*/
#define ASSERT_VALID_SFE(sfe) JS_ASSERT((sfe)->key == (sfe)->filename)
uint32
js_GetScriptFilenameFlags(const char *filename)
{
ScriptFilenameEntry *sfe;
sfe = FILENAME_TO_SFE(filename);
ASSERT_VALID_SFE(sfe);
return sfe->flags;
}
void
js_MarkScriptFilename(const char *filename)
{
ScriptFilenameEntry *sfe;
sfe = FILENAME_TO_SFE(filename);
ASSERT_VALID_SFE(sfe);
sfe->mark = JS_TRUE;
}
JS_STATIC_DLL_CALLBACK(intN)
js_script_filename_marker(JSHashEntry *he, intN i, void *arg)
{
ScriptFilenameEntry *sfe = (ScriptFilenameEntry *) he;
sfe->mark = JS_TRUE;
return HT_ENUMERATE_NEXT;
}
void
js_MarkScriptFilenames(JSRuntime *rt, JSBool keepAtoms)
{
JSCList *head, *link;
ScriptFilenamePrefix *sfp;
if (!rt->scriptFilenameTable)
return;
if (keepAtoms) {
JS_HashTableEnumerateEntries(rt->scriptFilenameTable,
js_script_filename_marker,
rt);
}
for (head = &rt->scriptFilenamePrefixes, link = head->next;
link != head;
link = link->next) {
sfp = (ScriptFilenamePrefix *) link;
js_MarkScriptFilename(sfp->name);
}
}
JS_STATIC_DLL_CALLBACK(intN)
js_script_filename_sweeper(JSHashEntry *he, intN i, void *arg)
{
ScriptFilenameEntry *sfe = (ScriptFilenameEntry *) he;
if (!sfe->mark)
return HT_ENUMERATE_REMOVE;
sfe->mark = JS_FALSE;
return HT_ENUMERATE_NEXT;
}
void
js_SweepScriptFilenames(JSRuntime *rt)
{
if (!rt->scriptFilenameTable)
return;
JS_HashTableEnumerateEntries(rt->scriptFilenameTable,
js_script_filename_sweeper,
rt);
#ifdef DEBUG_notme
#ifdef DEBUG_SFTBL
printf("script filename table savings so far: %u\n", sftbl_savings);
#endif
#endif
}
JSScript *
js_NewScript(JSContext *cx, uint32 length, uint32 nsrcnotes, uint32 ntrynotes)
{
JSScript *script;
/* Round up source note count to align script->trynotes for its type. */
if (ntrynotes)
nsrcnotes += JSTRYNOTE_ALIGNMASK;
script = (JSScript *) JS_malloc(cx,
sizeof(JSScript) +
length * sizeof(jsbytecode) +
nsrcnotes * sizeof(jssrcnote) +
ntrynotes * sizeof(JSTryNote));
if (!script)
return NULL;
memset(script, 0, sizeof(JSScript));
script->code = script->main = (jsbytecode *)(script + 1);
script->length = length;
script->version = cx->version;
if (ntrynotes) {
script->trynotes = (JSTryNote *)
((jsword)(SCRIPT_NOTES(script) + nsrcnotes) &
~(jsword)JSTRYNOTE_ALIGNMASK);
memset(script->trynotes, 0, ntrynotes * sizeof(JSTryNote));
}
return script;
}
JS_FRIEND_API(JSScript *)
js_NewScriptFromCG(JSContext *cx, JSCodeGenerator *cg, JSFunction *fun)
{
uint32 mainLength, prologLength, nsrcnotes, ntrynotes;
JSScript *script;
const char *filename;
mainLength = CG_OFFSET(cg);
prologLength = CG_PROLOG_OFFSET(cg);
CG_COUNT_FINAL_SRCNOTES(cg, nsrcnotes);
CG_COUNT_FINAL_TRYNOTES(cg, ntrynotes);
script = js_NewScript(cx, prologLength + mainLength, nsrcnotes, ntrynotes);
if (!script)
return NULL;
/* Now that we have script, error control flow must go to label bad. */
script->main += prologLength;
memcpy(script->code, CG_PROLOG_BASE(cg), prologLength * sizeof(jsbytecode));
memcpy(script->main, CG_BASE(cg), mainLength * sizeof(jsbytecode));
script->numGlobalVars = cg->treeContext.numGlobalVars;
if (!js_InitAtomMap(cx, &script->atomMap, &cg->atomList))
goto bad;
filename = cg->filename;
if (filename) {
script->filename = js_SaveScriptFilename(cx, filename);
if (!script->filename)
goto bad;
}
script->lineno = cg->firstLine;
script->depth = cg->maxStackDepth;
if (cg->principals) {
script->principals = cg->principals;
JSPRINCIPALS_HOLD(cx, script->principals);
}
if (!js_FinishTakingSrcNotes(cx, cg, SCRIPT_NOTES(script)))
goto bad;
if (script->trynotes)
js_FinishTakingTryNotes(cx, cg, script->trynotes);
/*
* We initialize fun->u.script to be the script constructed above
* so that the debugger has a valid FUN_SCRIPT(fun).
*/
if (fun) {
JS_ASSERT(FUN_INTERPRETED(fun) && !FUN_SCRIPT(fun));
fun->u.i.script = script;
if (cg->treeContext.flags & TCF_FUN_HEAVYWEIGHT)
fun->flags |= JSFUN_HEAVYWEIGHT;
}
/* Tell the debugger about this compiled script. */
js_CallNewScriptHook(cx, script, fun);
return script;
bad:
js_DestroyScript(cx, script);
return NULL;
}
JS_FRIEND_API(void)
js_CallNewScriptHook(JSContext *cx, JSScript *script, JSFunction *fun)
{
JSRuntime *rt;
JSNewScriptHook hook;
rt = cx->runtime;
hook = rt->newScriptHook;
if (hook) {
JS_KEEP_ATOMS(rt);
hook(cx, script->filename, script->lineno, script, fun,
rt->newScriptHookData);
JS_UNKEEP_ATOMS(rt);
}
}
JS_FRIEND_API(void)
js_CallDestroyScriptHook(JSContext *cx, JSScript *script)
{
JSRuntime *rt;
JSDestroyScriptHook hook;
rt = cx->runtime;
hook = rt->destroyScriptHook;
if (hook)
hook(cx, script, rt->destroyScriptHookData);
}
void
js_DestroyScript(JSContext *cx, JSScript *script)
{
js_CallDestroyScriptHook(cx, script);
JS_ClearScriptTraps(cx, script);
js_FreeAtomMap(cx, &script->atomMap);
if (script->principals)
JSPRINCIPALS_DROP(cx, script->principals);
if (JS_GSN_CACHE(cx).script == script)
JS_CLEAR_GSN_CACHE(cx);
JS_free(cx, script);
}
void
js_MarkScript(JSContext *cx, JSScript *script)
{
JSAtomMap *map;
uintN i, length;
JSAtom **vector;
map = &script->atomMap;
length = map->length;
vector = map->vector;
for (i = 0; i < length; i++)
GC_MARK_ATOM(cx, vector[i]);
if (script->filename)
js_MarkScriptFilename(script->filename);
}
typedef struct GSNCacheEntry {
JSDHashEntryHdr hdr;
jsbytecode *pc;
jssrcnote *sn;
} GSNCacheEntry;
#define GSN_CACHE_THRESHOLD 100
jssrcnote *
js_GetSrcNoteCached(JSContext *cx, JSScript *script, jsbytecode *pc)
{
ptrdiff_t target, offset;
GSNCacheEntry *entry;
jssrcnote *sn, *result;
uintN nsrcnotes;
target = PTRDIFF(pc, script->code, jsbytecode);
if ((uint32)target >= script->length)
return NULL;
if (JS_GSN_CACHE(cx).script == script) {
JS_METER_GSN_CACHE(cx, hits);
entry = (GSNCacheEntry *)
JS_DHashTableOperate(&JS_GSN_CACHE(cx).table, pc,
JS_DHASH_LOOKUP);
return entry->sn;
}
JS_METER_GSN_CACHE(cx, misses);
offset = 0;
for (sn = SCRIPT_NOTES(script); ; sn = SN_NEXT(sn)) {
if (SN_IS_TERMINATOR(sn)) {
result = NULL;
break;
}
offset += SN_DELTA(sn);
if (offset == target && SN_IS_GETTABLE(sn)) {
result = sn;
break;
}
}
if (JS_GSN_CACHE(cx).script != script &&
script->length >= GSN_CACHE_THRESHOLD) {
JS_CLEAR_GSN_CACHE(cx);
nsrcnotes = 0;
for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn);
sn = SN_NEXT(sn)) {
if (SN_IS_GETTABLE(sn))
++nsrcnotes;
}
if (!JS_DHashTableInit(&JS_GSN_CACHE(cx).table, JS_DHashGetStubOps(),
NULL, sizeof(GSNCacheEntry), nsrcnotes)) {
JS_GSN_CACHE(cx).table.ops = NULL;
} else {
pc = script->code;
for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn);
sn = SN_NEXT(sn)) {
pc += SN_DELTA(sn);
if (SN_IS_GETTABLE(sn)) {
entry = (GSNCacheEntry *)
JS_DHashTableOperate(&JS_GSN_CACHE(cx).table, pc,
JS_DHASH_ADD);
entry->pc = pc;
entry->sn = sn;
}
}
JS_GSN_CACHE(cx).script = script;
JS_METER_GSN_CACHE(cx, fills);
}
}
return result;
}
uintN
js_PCToLineNumber(JSContext *cx, JSScript *script, jsbytecode *pc)
{
JSAtom *atom;
JSFunction *fun;
uintN lineno;
ptrdiff_t offset, target;
jssrcnote *sn;
JSSrcNoteType type;
/* Cope with JSStackFrame.pc value prior to entering js_Interpret. */
if (!pc)
return 0;
/*
* Special case: function definition needs no line number note because
* the function's script contains its starting line number.
*/
if (*pc == JSOP_DEFFUN ||
(*pc == JSOP_LITOPX && pc[1 + LITERAL_INDEX_LEN] == JSOP_DEFFUN)) {
atom = js_GetAtom(cx, &script->atomMap,
(*pc == JSOP_DEFFUN)
? GET_ATOM_INDEX(pc)
: GET_LITERAL_INDEX(pc));
fun = (JSFunction *) JS_GetPrivate(cx, ATOM_TO_OBJECT(atom));
JS_ASSERT(FUN_INTERPRETED(fun));
return fun->u.i.script->lineno;
}
/*
* General case: walk through source notes accumulating their deltas,
* keeping track of line-number notes, until we pass the note for pc's
* offset within script->code.
*/
lineno = script->lineno;
offset = 0;
target = PTRDIFF(pc, script->code, jsbytecode);
for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
offset += SN_DELTA(sn);
type = (JSSrcNoteType) SN_TYPE(sn);
if (type == SRC_SETLINE) {
if (offset <= target)
lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
} else if (type == SRC_NEWLINE) {
if (offset <= target)
lineno++;
}
if (offset > target)
break;
}
return lineno;
}
/* The line number limit is the same as the jssrcnote offset limit. */
#define SN_LINE_LIMIT (SN_3BYTE_OFFSET_FLAG << 16)
jsbytecode *
js_LineNumberToPC(JSScript *script, uintN target)
{
ptrdiff_t offset, best;
uintN lineno, bestdiff, diff;
jssrcnote *sn;
JSSrcNoteType type;
offset = 0;
best = -1;
lineno = script->lineno;
bestdiff = SN_LINE_LIMIT;
for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
if (lineno == target)
goto out;
if (lineno > target) {
diff = lineno - target;
if (diff < bestdiff) {
bestdiff = diff;
best = offset;
}
}
offset += SN_DELTA(sn);
type = (JSSrcNoteType) SN_TYPE(sn);
if (type == SRC_SETLINE) {
lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
} else if (type == SRC_NEWLINE) {
lineno++;
}
}
if (best >= 0)
offset = best;
out:
return script->code + offset;
}
JS_FRIEND_API(uintN)
js_GetScriptLineExtent(JSScript *script)
{
uintN lineno;
jssrcnote *sn;
JSSrcNoteType type;
lineno = script->lineno;
for (sn = SCRIPT_NOTES(script); !SN_IS_TERMINATOR(sn); sn = SN_NEXT(sn)) {
type = (JSSrcNoteType) SN_TYPE(sn);
if (type == SRC_SETLINE) {
lineno = (uintN) js_GetSrcNoteOffset(sn, 0);
} else if (type == SRC_NEWLINE) {
lineno++;
}
}
return 1 + lineno - script->lineno;
}
#if JS_HAS_GENERATORS
jsbytecode *
js_FindFinallyHandler(JSScript *script, jsbytecode *pc)
{
JSTryNote *tn;
ptrdiff_t off;
JSOp op2;
tn = script->trynotes;
if (!tn)
return NULL;
off = pc - script->main;
if (off < 0)
return NULL;
JS_ASSERT(tn->catchStart != 0);
do {
if ((jsuword)(off - tn->start) < (jsuword)tn->length) {
/*
* We have a handler: is it the finally one, or a catch handler?
*
* Catch bytecode begins with: JSOP_SETSP JSOP_ENTERBLOCK
* Finally bytecode begins with: JSOP_SETSP JSOP_(GOSUB|EXCEPTION)
*/
pc = script->main + tn->catchStart;
JS_ASSERT(*pc == JSOP_SETSP);
op2 = pc[JSOP_SETSP_LENGTH];
if (op2 != JSOP_ENTERBLOCK) {
JS_ASSERT(op2 == JSOP_GOSUB || op2 == JSOP_EXCEPTION);
return pc;
}
}
} while ((++tn)->catchStart != 0);
return NULL;
}
#endif