📄 jsnum.c
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/* -*- 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): * IBM Corp. * * 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 number type and wrapper class. */#include "jsstddef.h"#if defined(XP_WIN) || defined(XP_OS2)#include <float.h>#endif#include <math.h>#include <stdlib.h>#include <string.h>#include "jstypes.h"#include "jsutil.h" /* Added by JSIFY */#include "jsapi.h"#include "jsatom.h"#include "jscntxt.h"#include "jsconfig.h"#include "jsdtoa.h"#include "jsgc.h"#include "jsinterp.h"#include "jsnum.h"#include "jsobj.h"#include "jsopcode.h"#include "jsprf.h"#include "jsstr.h"static JSBoolnum_isNaN(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ jsdouble x; if (!js_ValueToNumber(cx, argv[0], &x)) return JS_FALSE; *rval = BOOLEAN_TO_JSVAL(JSDOUBLE_IS_NaN(x)); return JS_TRUE;}static JSBoolnum_isFinite(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ jsdouble x; if (!js_ValueToNumber(cx, argv[0], &x)) return JS_FALSE; *rval = BOOLEAN_TO_JSVAL(JSDOUBLE_IS_FINITE(x)); return JS_TRUE;}static JSBoolnum_parseFloat(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ JSString *str; jsdouble d; const jschar *bp, *ep; str = js_ValueToString(cx, argv[0]); if (!str) return JS_FALSE; /* XXXbe js_strtod shouldn't require NUL termination */ bp = js_UndependString(cx, str); if (!bp) return JS_FALSE; if (!js_strtod(cx, bp, &ep, &d)) return JS_FALSE; if (ep == bp) { *rval = DOUBLE_TO_JSVAL(cx->runtime->jsNaN); return JS_TRUE; } return js_NewNumberValue(cx, d, rval);}/* See ECMA 15.1.2.2. */static JSBoolnum_parseInt(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ JSString *str; jsint radix; jsdouble d; const jschar *bp, *ep; str = js_ValueToString(cx, argv[0]); if (!str) return JS_FALSE; if (argc > 1) { if (!js_ValueToECMAInt32(cx, argv[1], &radix)) return JS_FALSE; } else radix = 0; if (radix != 0 && (radix < 2 || radix > 36)) { *rval = DOUBLE_TO_JSVAL(cx->runtime->jsNaN); return JS_TRUE; } /* XXXbe js_strtointeger shouldn't require NUL termination */ bp = js_UndependString(cx, str); if (!bp) return JS_FALSE; if (!js_strtointeger(cx, bp, &ep, radix, &d)) return JS_FALSE; if (ep == bp) { *rval = DOUBLE_TO_JSVAL(cx->runtime->jsNaN); return JS_TRUE; } return js_NewNumberValue(cx, d, rval);}const char js_Infinity_str[] = "Infinity";const char js_NaN_str[] = "NaN";const char js_isNaN_str[] = "isNaN";const char js_isFinite_str[] = "isFinite";const char js_parseFloat_str[] = "parseFloat";const char js_parseInt_str[] = "parseInt";static JSFunctionSpec number_functions[] = { {"isNaN", num_isNaN, 1,0,0}, {"isFinite", num_isFinite, 1,0,0}, {"parseFloat", num_parseFloat, 1,0,0}, {"parseInt", num_parseInt, 2,0,0}, {0,0,0,0,0}};static JSClass number_class = { "Number", JSCLASS_HAS_PRIVATE, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, JS_FinalizeStub, JSCLASS_NO_OPTIONAL_MEMBERS};static JSBoolNumber(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ jsdouble d; jsval v; if (argc != 0) { if (!js_ValueToNumber(cx, argv[0], &d)) return JS_FALSE; } else { d = 0.0; } if (!js_NewNumberValue(cx, d, &v)) return JS_FALSE; if (!(cx->fp->flags & JSFRAME_CONSTRUCTING)) { *rval = v; return JS_TRUE; } OBJ_SET_SLOT(cx, obj, JSSLOT_PRIVATE, v); return JS_TRUE;}#if JS_HAS_TOSOURCEstatic JSBoolnum_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ jsval v; jsdouble d; char numBuf[DTOSTR_STANDARD_BUFFER_SIZE], *numStr; char buf[64]; JSString *str; if (!JS_InstanceOf(cx, obj, &number_class, argv)) return JS_FALSE; v = OBJ_GET_SLOT(cx, obj, JSSLOT_PRIVATE); JS_ASSERT(JSVAL_IS_NUMBER(v)); d = JSVAL_IS_INT(v) ? (jsdouble)JSVAL_TO_INT(v) : *JSVAL_TO_DOUBLE(v); numStr = JS_dtostr(numBuf, sizeof numBuf, DTOSTR_STANDARD, 0, d); if (!numStr) { JS_ReportOutOfMemory(cx); return JS_FALSE; } JS_snprintf(buf, sizeof buf, "(new %s(%s))", number_class.name, numStr); str = JS_NewStringCopyZ(cx, buf); if (!str) return JS_FALSE; *rval = STRING_TO_JSVAL(str); return JS_TRUE;}#endif/* The buf must be big enough for MIN_INT to fit including '-' and '\0'. */static char *IntToString(jsint i, char *buf, size_t bufSize){ char *cp; jsuint u; u = (i < 0) ? -i : i; cp = buf + bufSize; /* one past last buffer cell */ *--cp = '\0'; /* null terminate the string to be */ /* * Build the string from behind. We use multiply and subtraction * instead of modulus because that's much faster. */ do { jsuint newu = u / 10; *--cp = (char)(u - newu * 10) + '0'; u = newu; } while (u != 0); if (i < 0) *--cp = '-'; return cp;}static JSBoolnum_toString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ JSString *string; string = JS_InternString (cx, "[type Object]"); if (string == NULL) return JS_FALSE; *rval = STRING_TO_JSVAL (string); return JS_TRUE;#if 0 jsval v; jsdouble d; jsint base; JSString *str; if (!JS_InstanceOf(cx, obj, &number_class, argv)) return JS_FALSE; v = OBJ_GET_SLOT(cx, obj, JSSLOT_PRIVATE); JS_ASSERT(JSVAL_IS_NUMBER(v)); d = JSVAL_IS_INT(v) ? (jsdouble)JSVAL_TO_INT(v) : *JSVAL_TO_DOUBLE(v); base = 10; if (argc != 0) { if (!js_ValueToECMAInt32(cx, argv[0], &base)) return JS_FALSE; if (base < 2 || base > 36) { char numBuf[12]; char *numStr = IntToString(base, numBuf, sizeof numBuf); JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_BAD_RADIX, numStr); return JS_FALSE; } } if (base == 10) str = js_NumberToString(cx, d); else { char *dStr = JS_dtobasestr(base, d); if (!dStr) { JS_ReportOutOfMemory(cx); return JS_FALSE; } str = JS_NewStringCopyZ(cx, dStr); free(dStr); } if (!str) return JS_FALSE; *rval = STRING_TO_JSVAL(str); return JS_TRUE;#endif}static JSBoolnum_toLocaleString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){/* * For now, forcibly ignore the first (or any) argument and return toString(). * ECMA allows this, although it doesn't 'encourage it'. * [The first argument is being reserved by ECMA and we don't want it confused * with a radix] */ return num_toString(cx, obj, 0, argv, rval);}static JSBoolnum_valueOf(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ if (!JS_InstanceOf(cx, obj, &number_class, argv)) return JS_FALSE; *rval = OBJ_GET_SLOT(cx, obj, JSSLOT_PRIVATE); return JS_TRUE;}#if JS_HAS_NUMBER_FORMATS#define MAX_PRECISION 100static JSBoolnum_to(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval, JSDToStrMode zeroArgMode, JSDToStrMode oneArgMode, jsint precisionMin, jsint precisionMax, jsint precisionOffset){ jsval v; jsdouble d, precision; JSString *str; char buf[DTOSTR_VARIABLE_BUFFER_SIZE(MAX_PRECISION+1)], *numStr; /* Use MAX_PRECISION+1 because precisionOffset can be 1 */ if (!JS_InstanceOf(cx, obj, &number_class, argv)) return JS_FALSE; v = OBJ_GET_SLOT(cx, obj, JSSLOT_PRIVATE); JS_ASSERT(JSVAL_IS_NUMBER(v)); d = JSVAL_IS_INT(v) ? (jsdouble)JSVAL_TO_INT(v) : *JSVAL_TO_DOUBLE(v); if (JSVAL_IS_VOID(argv[0])) { precision = 0.0; oneArgMode = zeroArgMode; } else { if (!js_ValueToNumber(cx, argv[0], &precision)) return JS_FALSE; precision = js_DoubleToInteger(precision); if (precision < precisionMin || precision > precisionMax) { numStr = JS_dtostr(buf, sizeof buf, DTOSTR_STANDARD, 0, precision); if (!numStr) JS_ReportOutOfMemory(cx); else JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_PRECISION_RANGE, numStr); return JS_FALSE; } } numStr = JS_dtostr(buf, sizeof buf, oneArgMode, (jsint)precision + precisionOffset, d); if (!numStr) { JS_ReportOutOfMemory(cx); return JS_FALSE; } str = JS_NewStringCopyZ(cx, numStr); if (!str) return JS_FALSE; *rval = STRING_TO_JSVAL(str); return JS_TRUE;}static JSBoolnum_toFixed(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ /* We allow a larger range of precision than ECMA requires; this is permitted by ECMA. */ return num_to(cx, obj, argc, argv, rval, DTOSTR_FIXED, DTOSTR_FIXED, -20, MAX_PRECISION, 0);}static JSBoolnum_toExponential(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ /* We allow a larger range of precision than ECMA requires; this is permitted by ECMA. */ return num_to(cx, obj, argc, argv, rval, DTOSTR_STANDARD_EXPONENTIAL, DTOSTR_EXPONENTIAL, 0, MAX_PRECISION, 1);}static JSBoolnum_toPrecision(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval){ /* We allow a larger range of precision than ECMA requires; this is permitted by ECMA. */ return num_to(cx, obj, argc, argv, rval, DTOSTR_STANDARD, DTOSTR_PRECISION, 1, MAX_PRECISION, 0);}#endif /* JS_HAS_NUMBER_FORMATS */static JSFunctionSpec number_methods[] = {#if JS_HAS_TOSOURCE {js_toSource_str, num_toSource, 0,0,0},#endif {js_toString_str, num_toString, 0,0,0}, {js_toLocaleString_str, num_toLocaleString, 0,0,0}, {js_valueOf_str, num_valueOf, 0,0,0},#if JS_HAS_NUMBER_FORMATS {"toFixed", num_toFixed, 1,0,0}, {"toExponential", num_toExponential, 1,0,0}, {"toPrecision", num_toPrecision, 1,0,0},#endif {0,0,0,0,0}};/* NB: Keep this in synch with number_constants[]. */enum nc_slot { NC_NaN, NC_POSITIVE_INFINITY, NC_NEGATIVE_INFINITY, NC_MAX_VALUE, NC_MIN_VALUE, NC_LIMIT};/* * Some to most C compilers forbid spelling these at compile time, or barf * if you try, so all but MAX_VALUE are set up by js_InitRuntimeNumberState * using union jsdpun. */static JSConstDoubleSpec number_constants[] = { {0, js_NaN_str, 0,{0,0,0}}, {0, "POSITIVE_INFINITY", 0,{0,0,0}}, {0, "NEGATIVE_INFINITY", 0,{0,0,0}}, {1.7976931348623157E+308, "MAX_VALUE", 0,{0,0,0}}, {0, "MIN_VALUE", 0,{0,0,0}}, {0,0,0,{0,0,0}}};static jsdouble NaN;#if (defined XP_WIN || defined XP_OS2) && \ !defined __MWERKS__ && \ (defined _M_IX86 || \ (defined __GNUC__ && !defined __MINGW32__))/* * Set the exception mask to mask all exceptions and set the FPU precision * to 53 bit mantissa. * On Alpha platform this is handled via Compiler option. */#define FIX_FPU() _control87(MCW_EM | PC_53, MCW_EM | MCW_PC)#else#define FIX_FPU() ((void)0)#endifJSBooljs_InitRuntimeNumberState(JSContext *cx){ JSRuntime *rt; jsdpun u; rt = cx->runtime; JS_ASSERT(!rt->jsNaN); FIX_FPU(); u.s.hi = JSDOUBLE_HI32_EXPMASK | JSDOUBLE_HI32_MANTMASK; u.s.lo = 0xffffffff; number_constants[NC_NaN].dval = NaN = u.d; rt->jsNaN = js_NewDouble(cx, NaN); if (!rt->jsNaN || !js_LockGCThing(cx, rt->jsNaN)) return JS_FALSE; u.s.hi = JSDOUBLE_HI32_EXPMASK; u.s.lo = 0x00000000; number_constants[NC_POSITIVE_INFINITY].dval = u.d; rt->jsPositiveInfinity = js_NewDouble(cx, u.d); if (!rt->jsPositiveInfinity || !js_LockGCThing(cx, rt->jsPositiveInfinity)) { return JS_FALSE; } u.s.hi = JSDOUBLE_HI32_SIGNBIT | JSDOUBLE_HI32_EXPMASK; u.s.lo = 0x00000000; number_constants[NC_NEGATIVE_INFINITY].dval = u.d; rt->jsNegativeInfinity = js_NewDouble(cx, u.d); if (!rt->jsNegativeInfinity || !js_LockGCThing(cx, rt->jsNegativeInfinity)) { return JS_FALSE; } u.s.hi = 0; u.s.lo = 1; number_constants[NC_MIN_VALUE].dval = u.d; return JS_TRUE;}voidjs_FinishRuntimeNumberState(JSContext *cx){ JSRuntime *rt = cx->runtime; js_UnlockGCThingRT(rt, rt->jsNaN); js_UnlockGCThingRT(rt, rt->jsNegativeInfinity); js_UnlockGCThingRT(rt, rt->jsPositiveInfinity); rt->jsNaN = NULL; rt->jsNegativeInfinity = NULL; rt->jsPositiveInfinity = NULL;}JSObject *js_InitNumberClass(JSContext *cx, JSObject *obj){ JSObject *proto, *ctor; JSRuntime *rt; /* XXX must do at least once per new thread, so do it per JSContext... */ FIX_FPU(); if (!JS_DefineFunctions(cx, obj, number_functions)) return NULL; proto = JS_InitClass(cx, obj, NULL, &number_class, Number, 1, NULL, number_methods, NULL, NULL); if (!proto || !(ctor = JS_GetConstructor(cx, proto))) return NULL; OBJ_SET_SLOT(cx, proto, JSSLOT_PRIVATE, JSVAL_ZERO); if (!JS_DefineConstDoubles(cx, ctor, number_constants)) return NULL; /* ECMA 15.1.1.1 */ rt = cx->runtime;
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