gecko-dev/js/src/jsapi.h

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** 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 ***** */

#ifndef jsapi_h___
#define jsapi_h___
/*
 * JavaScript API.
 */
#include <stddef.h>
#include <stdio.h>
#include "jspubtd.h"

JS_BEGIN_EXTERN_C

/*
 * Type tags stored in the low bits of a jsval.
 */
#define JSVAL_OBJECT            0x0     /* untagged reference to object */
#define JSVAL_INT               0x1     /* tagged 31-bit integer value */
#define JSVAL_DOUBLE            0x2     /* tagged reference to double */
#define JSVAL_STRING            0x4     /* tagged reference to string */
#define JSVAL_BOOLEAN           0x6     /* tagged boolean value */

/* Type tag bitfield length and derived macros. */
#define JSVAL_TAGBITS           3
#define JSVAL_TAGMASK           JS_BITMASK(JSVAL_TAGBITS)
#define JSVAL_TAG(v)            ((v) & JSVAL_TAGMASK)
#define JSVAL_SETTAG(v,t)       ((v) | (t))
#define JSVAL_CLRTAG(v)         ((v) & ~(jsval)JSVAL_TAGMASK)
#define JSVAL_ALIGN             JS_BIT(JSVAL_TAGBITS)

/* Predicates for type testing. */
#define JSVAL_IS_OBJECT(v)      (JSVAL_TAG(v) == JSVAL_OBJECT)
#define JSVAL_IS_NUMBER(v)      (JSVAL_IS_INT(v) || JSVAL_IS_DOUBLE(v))
#define JSVAL_IS_INT(v)         (((v) & JSVAL_INT) && (v) != JSVAL_VOID)
#define JSVAL_IS_DOUBLE(v)      (JSVAL_TAG(v) == JSVAL_DOUBLE)
#define JSVAL_IS_STRING(v)      (JSVAL_TAG(v) == JSVAL_STRING)
#define JSVAL_IS_BOOLEAN(v)     (JSVAL_TAG(v) == JSVAL_BOOLEAN)
#define JSVAL_IS_NULL(v)        ((v) == JSVAL_NULL)
#define JSVAL_IS_VOID(v)        ((v) == JSVAL_VOID)
#define JSVAL_IS_PRIMITIVE(v)   (!JSVAL_IS_OBJECT(v) || JSVAL_IS_NULL(v))

/* Objects, strings, and doubles are GC'ed. */
#define JSVAL_IS_GCTHING(v)     (!((v) & JSVAL_INT) && !JSVAL_IS_BOOLEAN(v))
#define JSVAL_TO_GCTHING(v)     ((void *)JSVAL_CLRTAG(v))
#define JSVAL_TO_OBJECT(v)      ((JSObject *)JSVAL_TO_GCTHING(v))
#define JSVAL_TO_DOUBLE(v)      ((jsdouble *)JSVAL_TO_GCTHING(v))
#define JSVAL_TO_STRING(v)      ((JSString *)JSVAL_TO_GCTHING(v))
#define OBJECT_TO_JSVAL(obj)    ((jsval)(obj))
#define DOUBLE_TO_JSVAL(dp)     JSVAL_SETTAG((jsval)(dp), JSVAL_DOUBLE)
#define STRING_TO_JSVAL(str)    JSVAL_SETTAG((jsval)(str), JSVAL_STRING)

/* Lock and unlock the GC thing held by a jsval. */
#define JSVAL_LOCK(cx,v)        (JSVAL_IS_GCTHING(v)                          \
                                 ? JS_LockGCThing(cx, JSVAL_TO_GCTHING(v))    \
                                 : JS_TRUE)
#define JSVAL_UNLOCK(cx,v)      (JSVAL_IS_GCTHING(v)                          \
                                 ? JS_UnlockGCThing(cx, JSVAL_TO_GCTHING(v))  \
                                 : JS_TRUE)

/* Domain limits for the jsval int type. */
#define JSVAL_INT_BITS          31
#define JSVAL_INT_POW2(n)       ((jsval)1 << (n))
#define JSVAL_INT_MIN           ((jsval)1 - JSVAL_INT_POW2(30))
#define JSVAL_INT_MAX           (JSVAL_INT_POW2(30) - 1)
#define INT_FITS_IN_JSVAL(i)    ((jsuint)((i)+JSVAL_INT_MAX) <= 2*JSVAL_INT_MAX)
#define JSVAL_TO_INT(v)         ((jsint)(v) >> 1)
#define INT_TO_JSVAL(i)         (((jsval)(i) << 1) | JSVAL_INT)

/* Convert between boolean and jsval. */
#define JSVAL_TO_BOOLEAN(v)     ((JSBool)((v) >> JSVAL_TAGBITS))
#define BOOLEAN_TO_JSVAL(b)     JSVAL_SETTAG((jsval)(b) << JSVAL_TAGBITS,     \
                                             JSVAL_BOOLEAN)

/* A private data pointer (2-byte-aligned) can be stored as an int jsval. */
#define JSVAL_TO_PRIVATE(v)     ((void *)((v) & ~JSVAL_INT))
#define PRIVATE_TO_JSVAL(p)     ((jsval)(p) | JSVAL_INT)

/* Property attributes, set in JSPropertySpec and passed to API functions. */
#define JSPROP_ENUMERATE        0x01    /* property is visible to for/in loop */
#define JSPROP_READONLY         0x02    /* not settable: assignment is no-op */
#define JSPROP_PERMANENT        0x04    /* property cannot be deleted */
#define JSPROP_EXPORTED         0x08    /* property is exported from object */
#define JSPROP_GETTER           0x10    /* property holds getter function */
#define JSPROP_SETTER           0x20    /* property holds setter function */
#define JSPROP_SHARED           0x40    /* don't allocate a value slot for this
                                           property; don't copy the property on
                                           set of the same-named property in an
                                           object that delegates to a prototype
                                           containing this property */
#define JSPROP_INDEX            0x80    /* name is actually (jsint) index */

/* Function flags, set in JSFunctionSpec and passed to JS_NewFunction etc. */
#define JSFUN_LAMBDA            0x08    /* expressed, not declared, function */
#define JSFUN_GETTER            JSPROP_GETTER
#define JSFUN_SETTER            JSPROP_SETTER
#define JSFUN_BOUND_METHOD      0x40    /* bind this to fun->object's parent */
#define JSFUN_HEAVYWEIGHT       0x80    /* activation requires a Call object */
#define JSFUN_FLAGS_MASK        0xf8    /* overlay JSFUN_* attributes */

/*
 * Well-known JS values.  The extern'd variables are initialized when the
 * first JSContext is created by JS_NewContext (see below).
 */
#define JSVAL_VOID              INT_TO_JSVAL(0 - JSVAL_INT_POW2(30))
#define JSVAL_NULL              OBJECT_TO_JSVAL(0)
#define JSVAL_ZERO              INT_TO_JSVAL(0)
#define JSVAL_ONE               INT_TO_JSVAL(1)
#define JSVAL_FALSE             BOOLEAN_TO_JSVAL(JS_FALSE)
#define JSVAL_TRUE              BOOLEAN_TO_JSVAL(JS_TRUE)

/*
 * Microseconds since the epoch, midnight, January 1, 1970 UTC.  See the
 * comment in jstypes.h regarding safe int64 usage.
 */
extern JS_PUBLIC_API(int64)
JS_Now();

/* Don't want to export data, so provide accessors for non-inline jsvals. */
extern JS_PUBLIC_API(jsval)
JS_GetNaNValue(JSContext *cx);

extern JS_PUBLIC_API(jsval)
JS_GetNegativeInfinityValue(JSContext *cx);

extern JS_PUBLIC_API(jsval)
JS_GetPositiveInfinityValue(JSContext *cx);

extern JS_PUBLIC_API(jsval)
JS_GetEmptyStringValue(JSContext *cx);

/*
 * Format is a string of the following characters (spaces are insignificant),
 * specifying the tabulated type conversions:
 *
 *   b      JSBool          Boolean
 *   c      uint16/jschar   ECMA uint16, Unicode char
 *   i      int32           ECMA int32
 *   u      uint32          ECMA uint32
 *   j      int32           Rounded int32 (coordinate)
 *   d      jsdouble        IEEE double
 *   I      jsdouble        Integral IEEE double
 *   s      char *          C string
 *   S      JSString *      Unicode string, accessed by a JSString pointer
 *   W      jschar *        Unicode character vector, 0-terminated (W for wide)
 *   o      JSObject *      Object reference
 *   f      JSFunction *    Function private
 *   v      jsval           Argument value (no conversion)
 *   *      N/A             Skip this argument (no vararg)
 *   /      N/A             End of required arguments
 *
 * The variable argument list after format must consist of &b, &c, &s, e.g.,
 * where those variables have the types given above.  For the pointer types
 * char *, JSString *, and JSObject *, the pointed-at memory returned belongs
 * to the JS runtime, not to the calling native code.  The runtime promises
 * to keep this memory valid so long as argv refers to allocated stack space
 * (so long as the native function is active).
 *
 * Fewer arguments than format specifies may be passed only if there is a /
 * in format after the last required argument specifier and argc is at least
 * the number of required arguments.  More arguments than format specifies
 * may be passed without error; it is up to the caller to deal with trailing
 * unconverted arguments.
 */
extern JS_PUBLIC_API(JSBool)
JS_ConvertArguments(JSContext *cx, uintN argc, jsval *argv, const char *format,
                    ...);

#ifdef va_start
extern JS_PUBLIC_API(JSBool)
JS_ConvertArgumentsVA(JSContext *cx, uintN argc, jsval *argv,
                      const char *format, va_list ap);
#endif

/*
 * Inverse of JS_ConvertArguments: scan format and convert trailing arguments
 * into jsvals, GC-rooted if necessary by the JS stack.  Return null on error,
 * and a pointer to the new argument vector on success.  Also return a stack
 * mark on success via *markp, in which case the caller must eventually clean
 * up by calling JS_PopArguments.
 *
 * Note that the number of actual arguments supplied is specified exclusively
 * by format, so there is no argc parameter.
 */
extern JS_PUBLIC_API(jsval *)
JS_PushArguments(JSContext *cx, void **markp, const char *format, ...);

#ifdef va_start
extern JS_PUBLIC_API(jsval *)
JS_PushArgumentsVA(JSContext *cx, void **markp, const char *format, va_list ap);
#endif

extern JS_PUBLIC_API(void)
JS_PopArguments(JSContext *cx, void *mark);

#ifdef JS_ARGUMENT_FORMATTER_DEFINED

/*
 * Add and remove a format string handler for JS_{Convert,Push}Arguments{,VA}.
 * The handler function has this signature (see jspubtd.h):
 *
 *   JSBool MyArgumentFormatter(JSContext *cx, const char *format,
 *                              JSBool fromJS, jsval **vpp, va_list *app);
 *
 * It should return true on success, and return false after reporting an error
 * or detecting an already-reported error.
 *
 * For a given format string, for example "AA", the formatter is called from
 * JS_ConvertArgumentsVA like so:
 *
 *   formatter(cx, "AA...", JS_TRUE, &sp, &ap);
 *
 * sp points into the arguments array on the JS stack, while ap points into
 * the stdarg.h va_list on the C stack.  The JS_TRUE passed for fromJS tells
 * the formatter to convert zero or more jsvals at sp to zero or more C values
 * accessed via pointers-to-values at ap, updating both sp (via *vpp) and ap
 * (via *app) to point past the converted arguments and their result pointers
 * on the C stack.
 *
 * When called from JS_PushArgumentsVA, the formatter is invoked thus:
 *
 *   formatter(cx, "AA...", JS_FALSE, &sp, &ap);
 *
 * where JS_FALSE for fromJS means to wrap the C values at ap according to the
 * format specifier and store them at sp, updating ap and sp appropriately.
 *
 * The "..." after "AA" is the rest of the format string that was passed into
 * JS_{Convert,Push}Arguments{,VA}.  The actual format trailing substring used
 * in each Convert or PushArguments call is passed to the formatter, so that
 * one such function may implement several formats, in order to share code.
 *
 * Remove just forgets about any handler associated with format.  Add does not
 * copy format, it points at the string storage allocated by the caller, which
 * is typically a string constant.  If format is in dynamic storage, it is up
 * to the caller to keep the string alive until Remove is called.
 */
extern JS_PUBLIC_API(JSBool)
JS_AddArgumentFormatter(JSContext *cx, const char *format,
                        JSArgumentFormatter formatter);

extern JS_PUBLIC_API(void)
JS_RemoveArgumentFormatter(JSContext *cx, const char *format);

#endif /* JS_ARGUMENT_FORMATTER_DEFINED */

extern JS_PUBLIC_API(JSBool)
JS_ConvertValue(JSContext *cx, jsval v, JSType type, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_ValueToObject(JSContext *cx, jsval v, JSObject **objp);

extern JS_PUBLIC_API(JSFunction *)
JS_ValueToFunction(JSContext *cx, jsval v);

extern JS_PUBLIC_API(JSFunction *)
JS_ValueToConstructor(JSContext *cx, jsval v);

extern JS_PUBLIC_API(JSString *)
JS_ValueToString(JSContext *cx, jsval v);

extern JS_PUBLIC_API(JSBool)
JS_ValueToNumber(JSContext *cx, jsval v, jsdouble *dp);

/*
 * Convert a value to a number, then to an int32, according to the ECMA rules
 * for ToInt32.
 */
extern JS_PUBLIC_API(JSBool)
JS_ValueToECMAInt32(JSContext *cx, jsval v, int32 *ip);

/*
 * Convert a value to a number, then to a uint32, according to the ECMA rules
 * for ToUint32.
 */
extern JS_PUBLIC_API(JSBool)
JS_ValueToECMAUint32(JSContext *cx, jsval v, uint32 *ip);

/*
 * Convert a value to a number, then to an int32 if it fits by rounding to
 * nearest; but failing with an error report if the double is out of range
 * or unordered.
 */
extern JS_PUBLIC_API(JSBool)
JS_ValueToInt32(JSContext *cx, jsval v, int32 *ip);

/*
 * ECMA ToUint16, for mapping a jsval to a Unicode point.
 */
extern JS_PUBLIC_API(JSBool)
JS_ValueToUint16(JSContext *cx, jsval v, uint16 *ip);

extern JS_PUBLIC_API(JSBool)
JS_ValueToBoolean(JSContext *cx, jsval v, JSBool *bp);

extern JS_PUBLIC_API(JSType)
JS_TypeOfValue(JSContext *cx, jsval v);

extern JS_PUBLIC_API(const char *)
JS_GetTypeName(JSContext *cx, JSType type);

/************************************************************************/

/*
 * Initialization, locking, contexts, and memory allocation.
 */
#define JS_NewRuntime       JS_Init
#define JS_DestroyRuntime   JS_Finish
#define JS_LockRuntime      JS_Lock
#define JS_UnlockRuntime    JS_Unlock

extern JS_PUBLIC_API(JSRuntime *)
JS_NewRuntime(uint32 maxbytes);

extern JS_PUBLIC_API(void)
JS_DestroyRuntime(JSRuntime *rt);

extern JS_PUBLIC_API(void)
JS_ShutDown(void);

JS_PUBLIC_API(void *)
JS_GetRuntimePrivate(JSRuntime *rt);

JS_PUBLIC_API(void)
JS_SetRuntimePrivate(JSRuntime *rt, void *data);

#ifdef JS_THREADSAFE

extern JS_PUBLIC_API(void)
JS_BeginRequest(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_EndRequest(JSContext *cx);

/* Yield to pending GC operations, regardless of request depth */
extern JS_PUBLIC_API(void)
JS_YieldRequest(JSContext *cx);

extern JS_PUBLIC_API(jsrefcount)
JS_SuspendRequest(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_ResumeRequest(JSContext *cx, jsrefcount saveDepth);

#endif /* JS_THREADSAFE */

extern JS_PUBLIC_API(void)
JS_Lock(JSRuntime *rt);

extern JS_PUBLIC_API(void)
JS_Unlock(JSRuntime *rt);

extern JS_PUBLIC_API(JSContext *)
JS_NewContext(JSRuntime *rt, size_t stackChunkSize);

extern JS_PUBLIC_API(void)
JS_DestroyContext(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_DestroyContextNoGC(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_DestroyContextMaybeGC(JSContext *cx);

extern JS_PUBLIC_API(void *)
JS_GetContextPrivate(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_SetContextPrivate(JSContext *cx, void *data);

extern JS_PUBLIC_API(JSRuntime *)
JS_GetRuntime(JSContext *cx);

extern JS_PUBLIC_API(JSContext *)
JS_ContextIterator(JSRuntime *rt, JSContext **iterp);

extern JS_PUBLIC_API(JSVersion)
JS_GetVersion(JSContext *cx);

extern JS_PUBLIC_API(JSVersion)
JS_SetVersion(JSContext *cx, JSVersion version);

extern JS_PUBLIC_API(const char *)
JS_VersionToString(JSVersion version);

extern JS_PUBLIC_API(JSVersion)
JS_StringToVersion(const char *string);

/*
 * JS options are orthogonal to version, and may be freely composed with one
 * another as well as with version.
 *
 * JSOPTION_VAROBJFIX is recommended -- see the comments associated with the
 * prototypes for JS_ExecuteScript, JS_EvaluateScript, etc.
 */
#define JSOPTION_STRICT         JS_BIT(0)       /* warn on dubious practice */
#define JSOPTION_WERROR         JS_BIT(1)       /* convert warning to error */
#define JSOPTION_VAROBJFIX      JS_BIT(2)       /* make JS_EvaluateScript use
                                                   the last object on its 'obj'
                                                   param's scope chain as the
                                                   ECMA 'variables object' */
#define JSOPTION_PRIVATE_IS_NSISUPPORTS \
                                JS_BIT(3)       /* context private data points
                                                   to an nsISupports subclass */
#define JSOPTION_COMPILE_N_GO   JS_BIT(4)       /* caller of JS_Compile*Script
                                                   promises to execute compiled
                                                   script once only; enables
                                                   compile-time scope chain
                                                   resolution of consts. */

extern JS_PUBLIC_API(uint32)
JS_GetOptions(JSContext *cx);

extern JS_PUBLIC_API(uint32)
JS_SetOptions(JSContext *cx, uint32 options);

extern JS_PUBLIC_API(uint32)
JS_ToggleOptions(JSContext *cx, uint32 options);

extern JS_PUBLIC_API(const char *)
JS_GetImplementationVersion(void);

extern JS_PUBLIC_API(JSObject *)
JS_GetGlobalObject(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_SetGlobalObject(JSContext *cx, JSObject *obj);

/*
 * Initialize standard JS class constructors, prototypes, and any top-level
 * functions and constants associated with the standard classes (e.g. isNaN
 * for Number).
 *
 * NB: This sets cx's global object to obj if it was null.
 */
extern JS_PUBLIC_API(JSBool)
JS_InitStandardClasses(JSContext *cx, JSObject *obj);

/*
 * Resolve id, which must contain either a string or an int, to a standard
 * class name in obj if possible, defining the class's constructor and/or
 * prototype and storing true in *resolved.  If id does not name a standard
 * class or a top-level property induced by initializing a standard class,
 * store false in *resolved and just return true.  Return false on error,
 * as usual for JSBool result-typed API entry points.
 *
 * This API can be called directly from a global object class's resolve op,
 * to define standard classes lazily.  The class's enumerate op should call
 * JS_EnumerateStandardClasses(cx, obj), to define eagerly during for..in
 * loops any classes not yet resolved lazily.
 */
extern JS_PUBLIC_API(JSBool)
JS_ResolveStandardClass(JSContext *cx, JSObject *obj, jsval id,
                        JSBool *resolved);

extern JS_PUBLIC_API(JSBool)
JS_EnumerateStandardClasses(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSObject *)
JS_GetScopeChain(JSContext *cx);

extern JS_PUBLIC_API(void *)
JS_malloc(JSContext *cx, size_t nbytes);

extern JS_PUBLIC_API(void *)
JS_realloc(JSContext *cx, void *p, size_t nbytes);

extern JS_PUBLIC_API(void)
JS_free(JSContext *cx, void *p);

extern JS_PUBLIC_API(char *)
JS_strdup(JSContext *cx, const char *s);

extern JS_PUBLIC_API(jsdouble *)
JS_NewDouble(JSContext *cx, jsdouble d);

extern JS_PUBLIC_API(JSBool)
JS_NewDoubleValue(JSContext *cx, jsdouble d, jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_NewNumberValue(JSContext *cx, jsdouble d, jsval *rval);

/*
 * A JS GC root is a pointer to a JSObject *, JSString *, or jsdouble * that
 * itself points into the GC heap (more recently, we support this extension:
 * a root may be a pointer to a jsval v for which JSVAL_IS_GCTHING(v) is true).
 *
 * Therefore, you never pass JSObject *obj to JS_AddRoot(cx, obj).  You always
 * call JS_AddRoot(cx, &obj), passing obj by reference.  And later, before obj
 * or the structure it is embedded within goes out of scope or is freed, you
 * must call JS_RemoveRoot(cx, &obj).
 *
 * Also, use JS_AddNamedRoot(cx, &structPtr->memberObj, "structPtr->memberObj")
 * in preference to JS_AddRoot(cx, &structPtr->memberObj), in order to identify
 * roots by their source callsites.  This way, you can find the callsite while
 * debugging if you should fail to do JS_RemoveRoot(cx, &structPtr->memberObj)
 * before freeing structPtr's memory.
 */
extern JS_PUBLIC_API(JSBool)
JS_AddRoot(JSContext *cx, void *rp);

#ifdef NAME_ALL_GC_ROOTS
#define JS_DEFINE_TO_TOKEN(def) #def
#define JS_DEFINE_TO_STRING(def) JS_DEFINE_TO_TOKEN(def)
#define JS_AddRoot(cx,rp) JS_AddNamedRoot((cx), (rp), (__FILE__ ":" JS_TOKEN_TO_STRING(__LINE__))
#endif

extern JS_PUBLIC_API(JSBool)
JS_AddNamedRoot(JSContext *cx, void *rp, const char *name);

extern JS_PUBLIC_API(JSBool)
JS_AddNamedRootRT(JSRuntime *rt, void *rp, const char *name);

extern JS_PUBLIC_API(JSBool)
JS_RemoveRoot(JSContext *cx, void *rp);

extern JS_PUBLIC_API(JSBool)
JS_RemoveRootRT(JSRuntime *rt, void *rp);

/*
 * The last GC thing of each type (object, string, double, external string
 * types) created on a given context is kept alive until another thing of the
 * same type is created, using a newborn root in the context.  These newborn
 * roots help native code protect newly-created GC-things from GC invocations
 * activated before those things can be rooted using local or global roots.
 *
 * However, the newborn roots can also entrain great gobs of garbage, so the
 * JS_GC entry point clears them for the context on which GC is being forced.
 * Embeddings may need to do likewise for all contexts.
 *
 * XXXbe See bug 40757 (http://bugzilla.mozilla.org/show_bug.cgi?id=40757),
 * which proposes switching (with an #ifdef, alas, if we want to maintain API
 * compatibility) to a JNI-like extensible local root frame stack model.
 */
extern JS_PUBLIC_API(void)
JS_ClearNewbornRoots(JSContext *cx);

#ifdef DEBUG
extern JS_PUBLIC_API(void)
JS_DumpNamedRoots(JSRuntime *rt,
                  void (*dump)(const char *name, void *rp, void *data),
                  void *data);
#endif

/*
 * Call JS_MapGCRoots to map the GC's roots table using map(rp, name, data).
 * The root is pointed at by rp; if the root is unnamed, name is null; data is
 * supplied from the third parameter to JS_MapGCRoots.
 *
 * The map function should return JS_MAP_GCROOT_REMOVE to cause the currently
 * enumerated root to be removed.  To stop enumeration, set JS_MAP_GCROOT_STOP
 * in the return value.  To keep on mapping, return JS_MAP_GCROOT_NEXT.  These
 * constants are flags; you can OR them together.
 *
 * This function acquires and releases rt's GC lock around the mapping of the
 * roots table, so the map function should run to completion in as few cycles
 * as possible.  Of course, map cannot call JS_GC, JS_MaybeGC, JS_BeginRequest,
 * or any JS API entry point that acquires locks, without double-tripping or
 * deadlocking on the GC lock.
 *
 * JS_MapGCRoots returns the count of roots that were successfully mapped.
 */
#define JS_MAP_GCROOT_NEXT      0       /* continue mapping entries */
#define JS_MAP_GCROOT_STOP      1       /* stop mapping entries */
#define JS_MAP_GCROOT_REMOVE    2       /* remove and free the current entry */

typedef intN
(* JS_DLL_CALLBACK JSGCRootMapFun)(void *rp, const char *name, void *data);

extern JS_PUBLIC_API(uint32)
JS_MapGCRoots(JSRuntime *rt, JSGCRootMapFun map, void *data);

extern JS_PUBLIC_API(JSBool)
JS_LockGCThing(JSContext *cx, void *thing);

extern JS_PUBLIC_API(JSBool)
JS_LockGCThingRT(JSRuntime *rt, void *thing);

extern JS_PUBLIC_API(JSBool)
JS_UnlockGCThing(JSContext *cx, void *thing);

extern JS_PUBLIC_API(JSBool)
JS_UnlockGCThingRT(JSRuntime *rt, void *thing);

/*
 * For implementors of JSObjectOps.mark, to mark a GC-thing reachable via a
 * property or other strong ref identified for debugging purposes by name.
 * The name argument's storage needs to live only as long as the call to
 * this routine.
 *
 * The final arg is used by GC_MARK_DEBUG code to build a ref path through
 * the GC's live thing graph.  Implementors of JSObjectOps.mark should pass
 * its final arg through to this function when marking all GC-things that are
 * directly reachable from the object being marked.
 *
 * See the JSMarkOp typedef in jspubtd.h, and the JSObjectOps struct below.
 */
extern JS_PUBLIC_API(void)
JS_MarkGCThing(JSContext *cx, void *thing, const char *name, void *arg);

extern JS_PUBLIC_API(void)
JS_GC(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_MaybeGC(JSContext *cx);

extern JS_PUBLIC_API(JSGCCallback)
JS_SetGCCallback(JSContext *cx, JSGCCallback cb);

extern JS_PUBLIC_API(JSGCCallback)
JS_SetGCCallbackRT(JSRuntime *rt, JSGCCallback cb);

extern JS_PUBLIC_API(JSBool)
JS_IsAboutToBeFinalized(JSContext *cx, void *thing);

/*
 * Add an external string finalizer, one created by JS_NewExternalString (see
 * below) using a type-code returned from this function, and that understands
 * how to free or release the memory pointed at by JS_GetStringChars(str).
 *
 * Return a nonnegative type index if there is room for finalizer in the
 * global GC finalizers table, else return -1.  If the engine is compiled
 * JS_THREADSAFE and used in a multi-threaded environment, this function must
 * be invoked on the primordial thread only, at startup -- or else the entire
 * program must single-thread itself while loading a module that calls this
 * function.
 */
extern JS_PUBLIC_API(intN)
JS_AddExternalStringFinalizer(JSStringFinalizeOp finalizer);

/*
 * Remove finalizer from the global GC finalizers table, returning its type
 * code if found, -1 if not found.
 *
 * As with JS_AddExternalStringFinalizer, there is a threading restriction
 * if you compile the engine JS_THREADSAFE: this function may be called for a
 * given finalizer pointer on only one thread; different threads may call to
 * remove distinct finalizers safely.
 *
 * You must ensure that all strings with finalizer's type have been collected
 * before calling this function.  Otherwise, string data will be leaked by the
 * GC, for want of a finalizer to call.
 */
extern JS_PUBLIC_API(intN)
JS_RemoveExternalStringFinalizer(JSStringFinalizeOp finalizer);

/*
 * Create a new JSString whose chars member refers to external memory, i.e.,
 * memory requiring special, type-specific finalization.  The type code must
 * be a nonnegative return value from JS_AddExternalStringFinalizer.
 */
extern JS_PUBLIC_API(JSString *)
JS_NewExternalString(JSContext *cx, jschar *chars, size_t length, intN type);

/*
 * Returns the external-string finalizer index for this string, or -1 if it is
 * an "internal" (native to JS engine) string.
 */
extern JS_PUBLIC_API(intN)
JS_GetExternalStringGCType(JSRuntime *rt, JSString *str);

/*
 * Sets maximum (if stack grows upward) or minimum (downward) legal stack byte
 * address in limitAddr for the thread or process stack used by cx.  To disable
 * stack size checking, pass 0 for limitAddr.
 */
extern JS_PUBLIC_API(void)
JS_SetThreadStackLimit(JSContext *cx, jsuword limitAddr);

/************************************************************************/

/*
 * Classes, objects, and properties.
 */

/* For detailed comments on the function pointer types, see jspubtd.h. */
struct JSClass {
    const char          *name;
    uint32              flags;

    /* Mandatory non-null function pointer members. */
    JSPropertyOp        addProperty;
    JSPropertyOp        delProperty;
    JSPropertyOp        getProperty;
    JSPropertyOp        setProperty;
    JSEnumerateOp       enumerate;
    JSResolveOp         resolve;
    JSConvertOp         convert;
    JSFinalizeOp        finalize;

    /* Optionally non-null members start here. */
    JSGetObjectOps      getObjectOps;
    JSCheckAccessOp     checkAccess;
    JSNative            call;
    JSNative            construct;
    JSXDRObjectOp       xdrObject;
    JSHasInstanceOp     hasInstance;
    JSMarkOp            mark;
    JSReserveSlotsOp    reserveSlots;
};

#define JSCLASS_HAS_PRIVATE             (1<<0)  /* objects have private slot */
#define JSCLASS_NEW_ENUMERATE           (1<<1)  /* has JSNewEnumerateOp hook */
#define JSCLASS_NEW_RESOLVE             (1<<2)  /* has JSNewResolveOp hook */
#define JSCLASS_PRIVATE_IS_NSISUPPORTS  (1<<3)  /* private is (nsISupports *) */
#define JSCLASS_SHARE_ALL_PROPERTIES    (1<<4)  /* all properties are SHARED */
#define JSCLASS_NEW_RESOLVE_GETS_START  (1<<5)  /* JSNewResolveOp gets starting
                                                   object in prototype chain
                                                   passed in via *objp in/out
                                                   parameter */

/*
 * To reserve slots fetched and stored via JS_Get/SetReservedSlot, bitwise-or
 * JSCLASS_HAS_RESERVED_SLOTS(n) into the initializer for JSClass.flags, where
 * n is a constant in [1, 255].  Reserved slots are indexed from 0 to n-1.
 */
#define JSCLASS_RESERVED_SLOTS_SHIFT    8       /* room for 8 flags below */
#define JSCLASS_RESERVED_SLOTS_WIDTH    8       /* and 16 above this field */
#define JSCLASS_RESERVED_SLOTS_MASK     JS_BITMASK(JSCLASS_RESERVED_SLOTS_WIDTH)
#define JSCLASS_HAS_RESERVED_SLOTS(n)   (((n) & JSCLASS_RESERVED_SLOTS_MASK)  \
                                         << JSCLASS_RESERVED_SLOTS_SHIFT)
#define JSCLASS_RESERVED_SLOTS(clasp)   (((clasp)->flags                      \
                                          >> JSCLASS_RESERVED_SLOTS_SHIFT)    \
                                         & JSCLASS_RESERVED_SLOTS_MASK)

/* Initializer for unused members of statically initialized JSClass structs. */
#define JSCLASS_NO_OPTIONAL_MEMBERS     0,0,0,0,0,0,0,0

/* For detailed comments on these function pointer types, see jspubtd.h. */
struct JSObjectOps {
    /* Mandatory non-null function pointer members. */
    JSNewObjectMapOp    newObjectMap;
    JSObjectMapOp       destroyObjectMap;
    JSLookupPropOp      lookupProperty;
    JSDefinePropOp      defineProperty;
    JSPropertyIdOp      getProperty;
    JSPropertyIdOp      setProperty;
    JSAttributesOp      getAttributes;
    JSAttributesOp      setAttributes;
    JSPropertyIdOp      deleteProperty;
    JSConvertOp         defaultValue;
    JSNewEnumerateOp    enumerate;
    JSCheckAccessIdOp   checkAccess;

    /* Optionally non-null members start here. */
    JSObjectOp          thisObject;
    JSPropertyRefOp     dropProperty;
    JSNative            call;
    JSNative            construct;
    JSXDRObjectOp       xdrObject;
    JSHasInstanceOp     hasInstance;
    JSSetObjectSlotOp   setProto;
    JSSetObjectSlotOp   setParent;
    JSMarkOp            mark;
    JSFinalizeOp        clear;
    JSGetRequiredSlotOp getRequiredSlot;
    JSSetRequiredSlotOp setRequiredSlot;
};

/*
 * Classes that expose JSObjectOps via a non-null getObjectOps class hook may
 * derive a property structure from this struct, return a pointer to it from
 * lookupProperty and defineProperty, and use the pointer to avoid rehashing
 * in getAttributes and setAttributes.
 *
 * The jsid type contains either an int jsval (see JSVAL_IS_INT above), or an
 * internal pointer that is opaque to users of this API, but which users may
 * convert from and to a jsval using JS_ValueToId and JS_IdToValue.
 */
struct JSProperty {
    jsid id;
};

struct JSIdArray {
    jsint length;
    jsid  vector[1];    /* actually, length jsid words */
};

extern JS_PUBLIC_API(void)
JS_DestroyIdArray(JSContext *cx, JSIdArray *ida);

extern JS_PUBLIC_API(JSBool)
JS_ValueToId(JSContext *cx, jsval v, jsid *idp);

extern JS_PUBLIC_API(JSBool)
JS_IdToValue(JSContext *cx, jsid id, jsval *vp);

#define JSRESOLVE_QUALIFIED     0x01    /* resolve a qualified property id */
#define JSRESOLVE_ASSIGNING     0x02    /* resolve on the left of assignment */

extern JS_PUBLIC_API(JSBool)
JS_PropertyStub(JSContext *cx, JSObject *obj, jsval id, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_EnumerateStub(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_ResolveStub(JSContext *cx, JSObject *obj, jsval id);

extern JS_PUBLIC_API(JSBool)
JS_ConvertStub(JSContext *cx, JSObject *obj, JSType type, jsval *vp);

extern JS_PUBLIC_API(void)
JS_FinalizeStub(JSContext *cx, JSObject *obj);

struct JSConstDoubleSpec {
    jsdouble        dval;
    const char      *name;
    uint8           flags;
    uint8           spare[3];
};

/*
 * To define an array element rather than a named property member, cast the
 * element's index to (const char *) and initialize name with it, and set the
 * JSPROP_INDEX bit in flags.
 */
struct JSPropertySpec {
    const char      *name;
    int8            tinyid;
    uint8           flags;
    JSPropertyOp    getter;
    JSPropertyOp    setter;
};

struct JSFunctionSpec {
    const char      *name;
    JSNative        call;
    uint8           nargs;
    uint8           flags;
    uint16          extra;      /* number of arg slots for local GC roots */
};

extern JS_PUBLIC_API(JSObject *)
JS_InitClass(JSContext *cx, JSObject *obj, JSObject *parent_proto,
             JSClass *clasp, JSNative constructor, uintN nargs,
             JSPropertySpec *ps, JSFunctionSpec *fs,
             JSPropertySpec *static_ps, JSFunctionSpec *static_fs);

#ifdef JS_THREADSAFE
extern JS_PUBLIC_API(JSClass *)
JS_GetClass(JSContext *cx, JSObject *obj);

#define JS_GET_CLASS(cx,obj) JS_GetClass(cx, obj)
#else
extern JS_PUBLIC_API(JSClass *)
JS_GetClass(JSObject *obj);

#define JS_GET_CLASS(cx,obj) JS_GetClass(obj)
#endif

extern JS_PUBLIC_API(JSBool)
JS_InstanceOf(JSContext *cx, JSObject *obj, JSClass *clasp, jsval *argv);

extern JS_PUBLIC_API(void *)
JS_GetPrivate(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_SetPrivate(JSContext *cx, JSObject *obj, void *data);

extern JS_PUBLIC_API(void *)
JS_GetInstancePrivate(JSContext *cx, JSObject *obj, JSClass *clasp,
                      jsval *argv);

extern JS_PUBLIC_API(JSObject *)
JS_GetPrototype(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_SetPrototype(JSContext *cx, JSObject *obj, JSObject *proto);

extern JS_PUBLIC_API(JSObject *)
JS_GetParent(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_SetParent(JSContext *cx, JSObject *obj, JSObject *parent);

extern JS_PUBLIC_API(JSObject *)
JS_GetConstructor(JSContext *cx, JSObject *proto);

/*
 * Get a unique identifier for obj, good for the lifetime of obj (even if it
 * is moved by a copying GC).  Return false on failure (likely out of memory),
 * and true with *idp containing the unique id on success.
 */
extern JS_PUBLIC_API(JSBool)
JS_GetObjectId(JSContext *cx, JSObject *obj, jsid *idp);

extern JS_PUBLIC_API(JSObject *)
JS_NewObject(JSContext *cx, JSClass *clasp, JSObject *proto, JSObject *parent);

extern JS_PUBLIC_API(JSBool)
JS_SealObject(JSContext *cx, JSObject *obj, JSBool deep);

extern JS_PUBLIC_API(JSObject *)
JS_ConstructObject(JSContext *cx, JSClass *clasp, JSObject *proto,
                   JSObject *parent);

extern JS_PUBLIC_API(JSObject *)
JS_ConstructObjectWithArguments(JSContext *cx, JSClass *clasp, JSObject *proto,
                                JSObject *parent, uintN argc, jsval *argv);

extern JS_PUBLIC_API(JSObject *)
JS_DefineObject(JSContext *cx, JSObject *obj, const char *name, JSClass *clasp,
                JSObject *proto, uintN attrs);

extern JS_PUBLIC_API(JSBool)
JS_DefineConstDoubles(JSContext *cx, JSObject *obj, JSConstDoubleSpec *cds);

extern JS_PUBLIC_API(JSBool)
JS_DefineProperties(JSContext *cx, JSObject *obj, JSPropertySpec *ps);

extern JS_PUBLIC_API(JSBool)
JS_DefineProperty(JSContext *cx, JSObject *obj, const char *name, jsval value,
                  JSPropertyOp getter, JSPropertyOp setter, uintN attrs);

/*
 * Determine the attributes (JSPROP_* flags) of a property on a given object.
 *
 * If the object does not have a property by that name, *foundp will be
 * JS_FALSE and the value of *attrsp is undefined.
 */
extern JS_PUBLIC_API(JSBool)
JS_GetPropertyAttributes(JSContext *cx, JSObject *obj, const char *name,
                         uintN *attrsp, JSBool *foundp);

/*
 * Set the attributes of a property on a given object.
 *
 * If the object does not have a property by that name, *foundp will be
 * JS_FALSE and nothing will be altered.
 */
extern JS_PUBLIC_API(JSBool)
JS_SetPropertyAttributes(JSContext *cx, JSObject *obj, const char *name,
                         uintN attrs, JSBool *foundp);

extern JS_PUBLIC_API(JSBool)
JS_DefinePropertyWithTinyId(JSContext *cx, JSObject *obj, const char *name,
                            int8 tinyid, jsval value,
                            JSPropertyOp getter, JSPropertyOp setter,
                            uintN attrs);

extern JS_PUBLIC_API(JSBool)
JS_AliasProperty(JSContext *cx, JSObject *obj, const char *name,
                 const char *alias);

extern JS_PUBLIC_API(JSBool)
JS_LookupProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_GetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_SetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_DeleteProperty(JSContext *cx, JSObject *obj, const char *name);

extern JS_PUBLIC_API(JSBool)
JS_DeleteProperty2(JSContext *cx, JSObject *obj, const char *name,
                   jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_DefineUCProperty(JSContext *cx, JSObject *obj,
                    const jschar *name, size_t namelen, jsval value,
                    JSPropertyOp getter, JSPropertyOp setter,
                    uintN attrs);

/*
 * Determine the attributes (JSPROP_* flags) of a property on a given object.
 *
 * If the object does not have a property by that name, *foundp will be
 * JS_FALSE and the value of *attrsp is undefined.
 */
extern JS_PUBLIC_API(JSBool)
JS_GetUCPropertyAttributes(JSContext *cx, JSObject *obj,
                           const jschar *name, size_t namelen,
                           uintN *attrsp, JSBool *foundp);

/*
 * Set the attributes of a property on a given object.
 *
 * If the object does not have a property by that name, *foundp will be
 * JS_FALSE and nothing will be altered.
 */
extern JS_PUBLIC_API(JSBool)
JS_SetUCPropertyAttributes(JSContext *cx, JSObject *obj,
                           const jschar *name, size_t namelen,
                           uintN attrs, JSBool *foundp);


extern JS_PUBLIC_API(JSBool)
JS_DefineUCPropertyWithTinyId(JSContext *cx, JSObject *obj,
                              const jschar *name, size_t namelen,
                              int8 tinyid, jsval value,
                              JSPropertyOp getter, JSPropertyOp setter,
                              uintN attrs);

extern JS_PUBLIC_API(JSBool)
JS_LookupUCProperty(JSContext *cx, JSObject *obj,
                    const jschar *name, size_t namelen,
                    jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_GetUCProperty(JSContext *cx, JSObject *obj,
                 const jschar *name, size_t namelen,
                 jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_SetUCProperty(JSContext *cx, JSObject *obj,
                 const jschar *name, size_t namelen,
                 jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_DeleteUCProperty2(JSContext *cx, JSObject *obj,
                     const jschar *name, size_t namelen,
                     jsval *rval);

extern JS_PUBLIC_API(JSObject *)
JS_NewArrayObject(JSContext *cx, jsint length, jsval *vector);

extern JS_PUBLIC_API(JSBool)
JS_IsArrayObject(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_GetArrayLength(JSContext *cx, JSObject *obj, jsuint *lengthp);

extern JS_PUBLIC_API(JSBool)
JS_SetArrayLength(JSContext *cx, JSObject *obj, jsuint length);

extern JS_PUBLIC_API(JSBool)
JS_HasArrayLength(JSContext *cx, JSObject *obj, jsuint *lengthp);

extern JS_PUBLIC_API(JSBool)
JS_DefineElement(JSContext *cx, JSObject *obj, jsint index, jsval value,
                 JSPropertyOp getter, JSPropertyOp setter, uintN attrs);

extern JS_PUBLIC_API(JSBool)
JS_AliasElement(JSContext *cx, JSObject *obj, const char *name, jsint alias);

extern JS_PUBLIC_API(JSBool)
JS_LookupElement(JSContext *cx, JSObject *obj, jsint index, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_GetElement(JSContext *cx, JSObject *obj, jsint index, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_SetElement(JSContext *cx, JSObject *obj, jsint index, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_DeleteElement(JSContext *cx, JSObject *obj, jsint index);

extern JS_PUBLIC_API(JSBool)
JS_DeleteElement2(JSContext *cx, JSObject *obj, jsint index, jsval *rval);

extern JS_PUBLIC_API(void)
JS_ClearScope(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSIdArray *)
JS_Enumerate(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_CheckAccess(JSContext *cx, JSObject *obj, jsid id, JSAccessMode mode,
               jsval *vp, uintN *attrsp);

extern JS_PUBLIC_API(JSCheckAccessOp)
JS_SetCheckObjectAccessCallback(JSRuntime *rt, JSCheckAccessOp acb);

extern JS_PUBLIC_API(JSBool)
JS_GetReservedSlot(JSContext *cx, JSObject *obj, uint32 index, jsval *vp);

extern JS_PUBLIC_API(JSBool)
JS_SetReservedSlot(JSContext *cx, JSObject *obj, uint32 index, jsval v);

/************************************************************************/

/*
 * Security protocol.
 */
struct JSPrincipals {
    char *codebase;
    void * (* JS_DLL_CALLBACK getPrincipalArray)(JSContext *cx, JSPrincipals *);
    JSBool (* JS_DLL_CALLBACK globalPrivilegesEnabled)(JSContext *cx, JSPrincipals *);

    /* Don't call "destroy"; use reference counting macros below. */
    jsrefcount refcount;
    void (* JS_DLL_CALLBACK destroy)(JSContext *cx, struct JSPrincipals *);
};

#ifdef JS_THREADSAFE
#define JSPRINCIPALS_HOLD(cx, principals)   JS_HoldPrincipals(cx,principals)
#define JSPRINCIPALS_DROP(cx, principals)   JS_DropPrincipals(cx,principals)

extern JS_PUBLIC_API(jsrefcount)
JS_HoldPrincipals(JSContext *cx, JSPrincipals *principals);

extern JS_PUBLIC_API(jsrefcount)
JS_DropPrincipals(JSContext *cx, JSPrincipals *principals);

#else
#define JSPRINCIPALS_HOLD(cx, principals)   (++(principals)->refcount)
#define JSPRINCIPALS_DROP(cx, principals)                                     \
    ((--(principals)->refcount == 0)                                          \
     ? ((*(principals)->destroy)((cx), (principals)), 0)                      \
     : (principals)->refcount)
#endif

extern JS_PUBLIC_API(JSPrincipalsTranscoder)
JS_SetPrincipalsTranscoder(JSRuntime *rt, JSPrincipalsTranscoder px);

extern JS_PUBLIC_API(JSObjectPrincipalsFinder)
JS_SetObjectPrincipalsFinder(JSContext *cx, JSObjectPrincipalsFinder fop);

/************************************************************************/

/*
 * Functions and scripts.
 */
extern JS_PUBLIC_API(JSFunction *)
JS_NewFunction(JSContext *cx, JSNative call, uintN nargs, uintN flags,
               JSObject *parent, const char *name);

extern JS_PUBLIC_API(JSObject *)
JS_GetFunctionObject(JSFunction *fun);

/*
 * Deprecated, useful only for diagnostics.  Use JS_GetFunctionId instead for
 * anonymous vs. "anonymous" disambiguation and Unicode fidelity.
 */
extern JS_PUBLIC_API(const char *)
JS_GetFunctionName(JSFunction *fun);

/*
 * Return the function's identifier as a JSString, or null if fun is unnamed.
 * The returned string lives as long as fun, so you don't need to root a saved
 * reference to it if fun is well-connected or rooted, and provided you bound
 * the use of the saved reference by fun's lifetime.
 *
 * Prefer JS_GetFunctionId over JS_GetFunctionName because it returns null for
 * truly anonymous functions, and because it doesn't chop to ISO-Latin-1 chars
 * from UTF-16-ish jschars.
 */
extern JS_PUBLIC_API(JSString *)
JS_GetFunctionId(JSFunction *fun);

/*
 * Return JSFUN_* flags for fun.
 */
extern JS_PUBLIC_API(uintN)
JS_GetFunctionFlags(JSFunction *fun);

/*
 * Infallible predicate to test whether obj is a function object (faster than
 * comparing obj's class name to "Function", but equivalent unless someone has
 * overwritten the "Function" identifier with a different constructor and then
 * created instances using that constructor that might be passed in as obj).
 */
extern JS_PUBLIC_API(JSBool)
JS_ObjectIsFunction(JSContext *cx, JSObject *obj);

extern JS_PUBLIC_API(JSBool)
JS_DefineFunctions(JSContext *cx, JSObject *obj, JSFunctionSpec *fs);

extern JS_PUBLIC_API(JSFunction *)
JS_DefineFunction(JSContext *cx, JSObject *obj, const char *name, JSNative call,
                  uintN nargs, uintN attrs);

extern JS_PUBLIC_API(JSObject *)
JS_CloneFunctionObject(JSContext *cx, JSObject *funobj, JSObject *parent);

/*
 * Given a buffer, return JS_FALSE if the buffer might become a valid
 * javascript statement with the addition of more lines.  Otherwise return
 * JS_TRUE.  The intent is to support interactive compilation - accumulate
 * lines in a buffer until JS_BufferIsCompilableUnit is true, then pass it to
 * the compiler.
 */
extern JS_PUBLIC_API(JSBool)
JS_BufferIsCompilableUnit(JSContext *cx, JSObject *obj,
                          const char *bytes, size_t length);

/*
 * The JSScript objects returned by the following functions refer to string and
 * other kinds of literals, including doubles and RegExp objects.  These
 * literals are vulnerable to garbage collection; to root script objects and
 * prevent literals from being collected, create a rootable object using
 * JS_NewScriptObject, and root the resulting object using JS_Add[Named]Root.
 */
extern JS_PUBLIC_API(JSScript *)
JS_CompileScript(JSContext *cx, JSObject *obj,
                 const char *bytes, size_t length,
                 const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSScript *)
JS_CompileScriptForPrincipals(JSContext *cx, JSObject *obj,
                              JSPrincipals *principals,
                              const char *bytes, size_t length,
                              const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSScript *)
JS_CompileUCScript(JSContext *cx, JSObject *obj,
                   const jschar *chars, size_t length,
                   const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSScript *)
JS_CompileUCScriptForPrincipals(JSContext *cx, JSObject *obj,
                                JSPrincipals *principals,
                                const jschar *chars, size_t length,
                                const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSScript *)
JS_CompileFile(JSContext *cx, JSObject *obj, const char *filename);

extern JS_PUBLIC_API(JSScript *)
JS_CompileFileHandle(JSContext *cx, JSObject *obj, const char *filename,
                     FILE *fh);

extern JS_PUBLIC_API(JSScript *)
JS_CompileFileHandleForPrincipals(JSContext *cx, JSObject *obj,
                                  const char *filename, FILE *fh,
                                  JSPrincipals *principals);

/*
 * NB: you must use JS_NewScriptObject and root a pointer to its return value
 * in order to keep a JSScript and its atoms safe from garbage collection after
 * creating the script via JS_Compile* and before a JS_ExecuteScript* call.
 * E.g., and without error checks:
 *
 *    JSScript *script = JS_CompileFile(cx, global, filename);
 *    JSObject *scrobj = JS_NewScriptObject(cx, script);
 *    JS_AddNamedRoot(cx, &scrobj, "scrobj");
 *    do {
 *        jsval result;
 *        JS_ExecuteScript(cx, global, script, &result);
 *        JS_GC();
 *    } while (!JSVAL_IS_BOOLEAN(result) || JSVAL_TO_BOOLEAN(result));
 *    JS_RemoveRoot(cx, &scrobj);
 */
extern JS_PUBLIC_API(JSObject *)
JS_NewScriptObject(JSContext *cx, JSScript *script);

/*
 * Infallible getter for a script's object.  If JS_NewScriptObject has not been
 * called on script yet, the return value will be null.
 */
extern JS_PUBLIC_API(JSObject *)
JS_GetScriptObject(JSScript *script);

extern JS_PUBLIC_API(void)
JS_DestroyScript(JSContext *cx, JSScript *script);

extern JS_PUBLIC_API(JSFunction *)
JS_CompileFunction(JSContext *cx, JSObject *obj, const char *name,
                   uintN nargs, const char **argnames,
                   const char *bytes, size_t length,
                   const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSFunction *)
JS_CompileFunctionForPrincipals(JSContext *cx, JSObject *obj,
                                JSPrincipals *principals, const char *name,
                                uintN nargs, const char **argnames,
                                const char *bytes, size_t length,
                                const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSFunction *)
JS_CompileUCFunction(JSContext *cx, JSObject *obj, const char *name,
                     uintN nargs, const char **argnames,
                     const jschar *chars, size_t length,
                     const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSFunction *)
JS_CompileUCFunctionForPrincipals(JSContext *cx, JSObject *obj,
                                  JSPrincipals *principals, const char *name,
                                  uintN nargs, const char **argnames,
                                  const jschar *chars, size_t length,
                                  const char *filename, uintN lineno);

extern JS_PUBLIC_API(JSString *)
JS_DecompileScript(JSContext *cx, JSScript *script, const char *name,
                   uintN indent);

/*
 * API extension: OR this into indent to avoid pretty-printing the decompiled
 * source resulting from JS_DecompileFunction{,Body}.
 */
#define JS_DONT_PRETTY_PRINT    ((uintN)0x8000)

extern JS_PUBLIC_API(JSString *)
JS_DecompileFunction(JSContext *cx, JSFunction *fun, uintN indent);

extern JS_PUBLIC_API(JSString *)
JS_DecompileFunctionBody(JSContext *cx, JSFunction *fun, uintN indent);

/*
 * NB: JS_ExecuteScript, JS_ExecuteScriptPart, and the JS_Evaluate*Script*
 * quadruplets all use the obj parameter as the initial scope chain header,
 * the 'this' keyword value, and the variables object (ECMA parlance for where
 * 'var' and 'function' bind names) of the execution context for script.
 *
 * Using obj as the variables object is problematic if obj's parent (which is
 * the scope chain link; see JS_SetParent and JS_NewObject) is not null: in
 * this case, variables created by 'var x = 0', e.g., go in obj, but variables
 * created by assignment to an unbound id, 'x = 0', go in the last object on
 * the scope chain linked by parent.
 *
 * ECMA calls that last scoping object the "global object", but note that many
 * embeddings have several such objects.  ECMA requires that "global code" be
 * executed with the variables object equal to this global object.  But these
 * JS API entry points provide freedom to execute code against a "sub-global",
 * i.e., a parented or scoped object, in which case the variables object will
 * differ from the last object on the scope chain, resulting in confusing and
 * non-ECMA explicit vs. implicit variable creation.
 *
 * Caveat embedders: unless you already depend on this buggy variables object
 * binding behavior, you should call JS_SetOptions(cx, JSOPTION_VAROBJFIX) or
 * JS_SetOptions(cx, JS_GetOptions(cx) | JSOPTION_VAROBJFIX) -- the latter if
 * someone may have set other options on cx already -- for each context in the
 * application, if you pass parented objects as the obj parameter, or may ever
 * pass such objects in the future.
 *
 * Why a runtime option?  The alternative is to add six or so new API entry
 * points with signatures matching the following six, and that doesn't seem
 * worth the code bloat cost.  Such new entry points would probably have less
 * obvious names, too, so would not tend to be used.  The JS_SetOption call,
 * OTOH, can be more easily hacked into existing code that does not depend on
 * the bug; such code can continue to use the familiar JS_EvaluateScript,
 * etc., entry points.
 */
extern JS_PUBLIC_API(JSBool)
JS_ExecuteScript(JSContext *cx, JSObject *obj, JSScript *script, jsval *rval);

/*
 * Execute either the function-defining prolog of a script, or the script's
 * main body, but not both.
 */
typedef enum JSExecPart { JSEXEC_PROLOG, JSEXEC_MAIN } JSExecPart;

extern JS_PUBLIC_API(JSBool)
JS_ExecuteScriptPart(JSContext *cx, JSObject *obj, JSScript *script,
                     JSExecPart part, jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_EvaluateScript(JSContext *cx, JSObject *obj,
                  const char *bytes, uintN length,
                  const char *filename, uintN lineno,
                  jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_EvaluateScriptForPrincipals(JSContext *cx, JSObject *obj,
                               JSPrincipals *principals,
                               const char *bytes, uintN length,
                               const char *filename, uintN lineno,
                               jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_EvaluateUCScript(JSContext *cx, JSObject *obj,
                    const jschar *chars, uintN length,
                    const char *filename, uintN lineno,
                    jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_EvaluateUCScriptForPrincipals(JSContext *cx, JSObject *obj,
                                 JSPrincipals *principals,
                                 const jschar *chars, uintN length,
                                 const char *filename, uintN lineno,
                                 jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_CallFunction(JSContext *cx, JSObject *obj, JSFunction *fun, uintN argc,
                jsval *argv, jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_CallFunctionName(JSContext *cx, JSObject *obj, const char *name, uintN argc,
                    jsval *argv, jsval *rval);

extern JS_PUBLIC_API(JSBool)
JS_CallFunctionValue(JSContext *cx, JSObject *obj, jsval fval, uintN argc,
                     jsval *argv, jsval *rval);

extern JS_PUBLIC_API(JSBranchCallback)
JS_SetBranchCallback(JSContext *cx, JSBranchCallback cb);

extern JS_PUBLIC_API(JSBool)
JS_IsRunning(JSContext *cx);

extern JS_PUBLIC_API(JSBool)
JS_IsConstructing(JSContext *cx);

/*
 * Returns true if a script is executing and its current bytecode is a set
 * (assignment) operation, even if there are native (no script) stack frames
 * between the script and the caller to JS_IsAssigning.
 */
extern JS_FRIEND_API(JSBool)
JS_IsAssigning(JSContext *cx);

/*
 * Set the second return value, which should be a string or int jsval that
 * identifies a property in the returned object, to form an ECMA reference
 * type value (obj, id).  Only native methods can return reference types,
 * and if the returned value is used on the left-hand side of an assignment
 * op, the identified property will be set.  If the return value is in an
 * r-value, the interpreter just gets obj[id]'s value.
 */
extern JS_PUBLIC_API(void)
JS_SetCallReturnValue2(JSContext *cx, jsval v);

/************************************************************************/

/*
 * Strings.
 *
 * NB: JS_NewString takes ownership of bytes on success, avoiding a copy; but
 * on error (signified by null return), it leaves bytes owned by the caller.
 * So the caller must free bytes in the error case, if it has no use for them.
 * In contrast, all the JS_New*StringCopy* functions do not take ownership of
 * the character memory passed to them -- they copy it.
 */
extern JS_PUBLIC_API(JSString *)
JS_NewString(JSContext *cx, char *bytes, size_t length);

extern JS_PUBLIC_API(JSString *)
JS_NewStringCopyN(JSContext *cx, const char *s, size_t n);

extern JS_PUBLIC_API(JSString *)
JS_NewStringCopyZ(JSContext *cx, const char *s);

extern JS_PUBLIC_API(JSString *)
JS_InternString(JSContext *cx, const char *s);

extern JS_PUBLIC_API(JSString *)
JS_NewUCString(JSContext *cx, jschar *chars, size_t length);

extern JS_PUBLIC_API(JSString *)
JS_NewUCStringCopyN(JSContext *cx, const jschar *s, size_t n);

extern JS_PUBLIC_API(JSString *)
JS_NewUCStringCopyZ(JSContext *cx, const jschar *s);

extern JS_PUBLIC_API(JSString *)
JS_InternUCStringN(JSContext *cx, const jschar *s, size_t length);

extern JS_PUBLIC_API(JSString *)
JS_InternUCString(JSContext *cx, const jschar *s);

extern JS_PUBLIC_API(char *)
JS_GetStringBytes(JSString *str);

extern JS_PUBLIC_API(jschar *)
JS_GetStringChars(JSString *str);

extern JS_PUBLIC_API(size_t)
JS_GetStringLength(JSString *str);

extern JS_PUBLIC_API(intN)
JS_CompareStrings(JSString *str1, JSString *str2);

/*
 * Mutable string support.  A string's characters are never mutable in this JS
 * implementation, but a growable string has a buffer that can be reallocated,
 * and a dependent string is a substring of another (growable, dependent, or
 * immutable) string.  The direct data members of the (opaque to API clients)
 * JSString struct may be changed in a single-threaded way for growable and
 * dependent strings.
 *
 * Therefore mutable strings cannot be used by more than one thread at a time.
 * You may call JS_MakeStringImmutable to convert the string from a mutable
 * (growable or dependent) string to an immutable (and therefore thread-safe)
 * string.  The engine takes care of converting growable and dependent strings
 * to immutable for you if you store strings in multi-threaded objects using
 * JS_SetProperty or kindred API entry points.
 *
 * If you store a JSString pointer in a native data structure that is (safely)
 * accessible to multiple threads, you must call JS_MakeStringImmutable before
 * retiring the store.
 */
extern JS_PUBLIC_API(JSString *)
JS_NewGrowableString(JSContext *cx, jschar *chars, size_t length);

/*
 * Create a dependent string, i.e., a string that owns no character storage,
 * but that refers to a slice of another string's chars.  Dependent strings
 * are mutable by definition, so the thread safety comments above apply.
 */
extern JS_PUBLIC_API(JSString *)
JS_NewDependentString(JSContext *cx, JSString *str, size_t start,
                      size_t length);

/*
 * Concatenate two strings, resulting in a new growable string.  If you create
 * the left string and pass it to JS_ConcatStrings on a single thread, try to
 * use JS_NewGrowableString to create the left string -- doing so helps Concat
 * avoid allocating a new buffer for the result and copying left's chars into
 * the new buffer.  See above for thread safety comments.
 */
extern JS_PUBLIC_API(JSString *)
JS_ConcatStrings(JSContext *cx, JSString *left, JSString *right);

/*
 * Convert a dependent string into an independent one.  This function does not
 * change the string's mutability, so the thread safety comments above apply.
 */
extern JS_PUBLIC_API(const jschar *)
JS_UndependString(JSContext *cx, JSString *str);

/*
 * Convert a mutable string (either growable or dependent) into an immutable,
 * thread-safe one.
 */
extern JS_PUBLIC_API(JSBool)
JS_MakeStringImmutable(JSContext *cx, JSString *str);

/************************************************************************/

/*
 * Locale specific string conversion callback.
 */
struct JSLocaleCallbacks {
    JSLocaleToUpperCase     localeToUpperCase;
    JSLocaleToLowerCase     localeToLowerCase;
    JSLocaleCompare         localeCompare;
};

/*
 * Establish locale callbacks. The pointer must persist as long as the
 * JSContext.  Passing NULL restores the default behaviour.
 */
extern JS_PUBLIC_API(void)
JS_SetLocaleCallbacks(JSContext *cx, JSLocaleCallbacks *callbacks);

/*
 * Return the address of the current locale callbacks struct, which may
 * be NULL.
 */
extern JS_PUBLIC_API(JSLocaleCallbacks *)
JS_GetLocaleCallbacks(JSContext *cx);

/************************************************************************/

/*
 * Error reporting.
 */

/*
 * Report an exception represented by the sprintf-like conversion of format
 * and its arguments.  This exception message string is passed to a pre-set
 * JSErrorReporter function (set by JS_SetErrorReporter; see jspubtd.h for
 * the JSErrorReporter typedef).
 */
extern JS_PUBLIC_API(void)
JS_ReportError(JSContext *cx, const char *format, ...);

/*
 * Use an errorNumber to retrieve the format string, args are char *
 */
extern JS_PUBLIC_API(void)
JS_ReportErrorNumber(JSContext *cx, JSErrorCallback errorCallback,
                     void *userRef, const uintN errorNumber, ...);

/*
 * Use an errorNumber to retrieve the format string, args are jschar *
 */
extern JS_PUBLIC_API(void)
JS_ReportErrorNumberUC(JSContext *cx, JSErrorCallback errorCallback,
                     void *userRef, const uintN errorNumber, ...);

/*
 * As above, but report a warning instead (JSREPORT_IS_WARNING(report.flags)).
 * Return true if there was no error trying to issue the warning, and if the
 * warning was not converted into an error due to the JSOPTION_WERROR option
 * being set, false otherwise.
 */
extern JS_PUBLIC_API(JSBool)
JS_ReportWarning(JSContext *cx, const char *format, ...);

extern JS_PUBLIC_API(JSBool)
JS_ReportErrorFlagsAndNumber(JSContext *cx, uintN flags,
                             JSErrorCallback errorCallback, void *userRef,
                             const uintN errorNumber, ...);

extern JS_PUBLIC_API(JSBool)
JS_ReportErrorFlagsAndNumberUC(JSContext *cx, uintN flags,
                               JSErrorCallback errorCallback, void *userRef,
                               const uintN errorNumber, ...);

/*
 * Complain when out of memory.
 */
extern JS_PUBLIC_API(void)
JS_ReportOutOfMemory(JSContext *cx);

struct JSErrorReport {
    const char      *filename;      /* source file name, URL, etc., or null */
    uintN           lineno;         /* source line number */
    const char      *linebuf;       /* offending source line without final \n */
    const char      *tokenptr;      /* pointer to error token in linebuf */
    const jschar    *uclinebuf;     /* unicode (original) line buffer */
    const jschar    *uctokenptr;    /* unicode (original) token pointer */
    uintN           flags;          /* error/warning, etc. */
    uintN           errorNumber;    /* the error number, e.g. see js.msg */
    const jschar    *ucmessage;     /* the (default) error message */
    const jschar    **messageArgs;  /* arguments for the error message */
};

/*
 * JSErrorReport flag values.  These may be freely composed.
 */
#define JSREPORT_ERROR      0x0     /* pseudo-flag for default case */
#define JSREPORT_WARNING    0x1     /* reported via JS_ReportWarning */
#define JSREPORT_EXCEPTION  0x2     /* exception was thrown */
#define JSREPORT_STRICT     0x4     /* error or warning due to strict option */

/*
 * If JSREPORT_EXCEPTION is set, then a JavaScript-catchable exception
 * has been thrown for this runtime error, and the host should ignore it.
 * Exception-aware hosts should also check for JS_IsExceptionPending if
 * JS_ExecuteScript returns failure, and signal or propagate the exception, as
 * appropriate.
 */
#define JSREPORT_IS_WARNING(flags)      (((flags) & JSREPORT_WARNING) != 0)
#define JSREPORT_IS_EXCEPTION(flags)    (((flags) & JSREPORT_EXCEPTION) != 0)
#define JSREPORT_IS_STRICT(flags)       (((flags) & JSREPORT_STRICT) != 0)

extern JS_PUBLIC_API(JSErrorReporter)
JS_SetErrorReporter(JSContext *cx, JSErrorReporter er);

/************************************************************************/

/*
 * Regular Expressions.
 */
#define JSREG_FOLD      0x01    /* fold uppercase to lowercase */
#define JSREG_GLOB      0x02    /* global exec, creates array of matches */
#define JSREG_MULTILINE 0x04    /* treat ^ and $ as begin and end of line */

extern JS_PUBLIC_API(JSObject *)
JS_NewRegExpObject(JSContext *cx, char *bytes, size_t length, uintN flags);

extern JS_PUBLIC_API(JSObject *)
JS_NewUCRegExpObject(JSContext *cx, jschar *chars, size_t length, uintN flags);

extern JS_PUBLIC_API(void)
JS_SetRegExpInput(JSContext *cx, JSString *input, JSBool multiline);

extern JS_PUBLIC_API(void)
JS_ClearRegExpStatics(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_ClearRegExpRoots(JSContext *cx);

/* TODO: compile, exec, get/set other statics... */

/************************************************************************/

extern JS_PUBLIC_API(JSBool)
JS_IsExceptionPending(JSContext *cx);

extern JS_PUBLIC_API(JSBool)
JS_GetPendingException(JSContext *cx, jsval *vp);

extern JS_PUBLIC_API(void)
JS_SetPendingException(JSContext *cx, jsval v);

extern JS_PUBLIC_API(void)
JS_ClearPendingException(JSContext *cx);

/*
 * Save the current exception state.  This takes a snapshot of cx's current
 * exception state without making any change to that state.
 *
 * The returned state pointer MUST be passed later to JS_RestoreExceptionState
 * (to restore that saved state, overriding any more recent state) or else to
 * JS_DropExceptionState (to free the state struct in case it is not correct
 * or desirable to restore it).  Both Restore and Drop free the state struct,
 * so callers must stop using the pointer returned from Save after calling the
 * Release or Drop API.
 */
extern JS_PUBLIC_API(JSExceptionState *)
JS_SaveExceptionState(JSContext *cx);

extern JS_PUBLIC_API(void)
JS_RestoreExceptionState(JSContext *cx, JSExceptionState *state);

extern JS_PUBLIC_API(void)
JS_DropExceptionState(JSContext *cx, JSExceptionState *state);

/*
 * If the given value is an exception object that originated from an error,
 * the exception will contain an error report struct, and this API will return
 * the address of that struct.  Otherwise, it returns NULL.  The lifetime of
 * the error report struct that might be returned is the same as the lifetime
 * of the exception object.
 */
extern JS_PUBLIC_API(JSErrorReport *)
JS_ErrorFromException(JSContext *cx, jsval v);

#ifdef JS_THREADSAFE

/*
 * Associate the current thread with the given context.  This is done
 * implicitly by JS_NewContext.
 *
 * Returns the old thread id for this context, which should be treated as
 * an opaque value.  This value is provided for comparison to 0, which
 * indicates that ClearContextThread has been called on this context
 * since the last SetContextThread, or non-0, which indicates the opposite.
 */
extern JS_PUBLIC_API(jsword)
JS_GetContextThread(JSContext *cx);

extern JS_PUBLIC_API(jsword)
JS_SetContextThread(JSContext *cx);

extern JS_PUBLIC_API(jsword)
JS_ClearContextThread(JSContext *cx);

#endif /* JS_THREADSAFE */

/************************************************************************/

JS_END_EXTERN_C

#endif /* jsapi_h___ */