jsarray.c

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    chars[nchars] = 0;
    str = js_NewString(cx, chars, nchars, 0);
    if (!str) {
        free(chars);
        return JS_FALSE;
    }
    *rval = STRING_TO_JSVAL(str);
    return JS_TRUE;
}

static jschar   comma_space_ucstr[] = {',', ' ', 0};
static jschar   comma_ucstr[]       = {',', 0};
static JSString comma_space         = {2, comma_space_ucstr};
static JSString comma               = {1, comma_ucstr};

#if JS_HAS_TOSOURCE
static JSBool
array_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
               jsval *rval)
{
    return array_join_sub(cx, obj, &comma_space, JS_TRUE, rval, JS_FALSE);
}
#endif

static JSBool
array_toString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
               jsval *rval)
{
    JSBool literalize;

    /*
     * JS1.2 arrays convert to array literals, with a comma followed by a space
     * between each element.
     */
    literalize = (cx->version == JSVERSION_1_2);
    return array_join_sub(cx, obj, literalize ? &comma_space : &comma,
                          literalize, rval, JS_FALSE);
}

static JSBool
array_toLocaleString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
               jsval *rval)
{
    /*
     *  Passing comma here as the separator. Need a way to get a
     *  locale-specific version.
     */
    return array_join_sub(cx, obj, &comma, JS_FALSE, rval, JS_TRUE);
}

static JSBool
InitArrayElements(JSContext *cx, JSObject *obj, jsuint length, jsval *vector)
{
    jsuint index;
    jsid id;

    for (index = 0; index < length; index++) {
        if (!IndexToId(cx, index, &id))
            return JS_FALSE;
        if (!OBJ_SET_PROPERTY(cx, obj, id, &vector[index]))
            return JS_FALSE;
    }
    return JS_TRUE;
}

static JSBool
InitArrayObject(JSContext *cx, JSObject *obj, jsuint length, jsval *vector)
{
    jsval v;
    jsid id;

    if (!IndexToValue(cx, length, &v))
        return JS_FALSE;
    id = (jsid) cx->runtime->atomState.lengthAtom;
    if (!OBJ_DEFINE_PROPERTY(cx, obj, id, v,
                             array_length_getter, array_length_setter,
                             JSPROP_PERMANENT,
                             NULL)) {
          return JS_FALSE;
    }
    if (!vector)
        return JS_TRUE;
    return InitArrayElements(cx, obj, length, vector);
}

#if JS_HAS_SOME_PERL_FUN
/*
 * Perl-inspired join, reverse, and sort.
 */
static JSBool
array_join(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    JSString *str;

    if (JSVAL_IS_VOID(argv[0]))
        return array_join_sub(cx, obj, &comma, JS_FALSE, rval, JS_FALSE);
    str = js_ValueToString(cx, argv[0]);
    if (!str)
        return JS_FALSE;
    argv[0] = STRING_TO_JSVAL(str);
    return array_join_sub(cx, obj, str, JS_FALSE, rval, JS_FALSE);
}

static JSBool
array_reverse(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
              jsval *rval)
{
    jsuint len, half, i;
    jsid id, id2;
    jsval v, v2;

    if (!js_GetLengthProperty(cx, obj, &len))
        return JS_FALSE;

    half = len / 2;
    for (i = 0; i < half; i++) {
        if (!IndexToId(cx, i, &id))
            return JS_FALSE;
        if (!IndexToId(cx, len - i - 1, &id2))
            return JS_FALSE;
        if (!OBJ_GET_PROPERTY(cx, obj, id, &v))
            return JS_FALSE;
        if (!OBJ_GET_PROPERTY(cx, obj, id2, &v2))
            return JS_FALSE;

#if JS_HAS_SPARSE_ARRAYS
        /* This part isn't done yet. */

        if (!OBJ_LOOKUP_PROPERTY(cx, obj, id, &obj2, &prop))
            return JS_FALSE;
        if (!prop) {
            OBJ_DELETE_PROPERTY(cx, obj, id2, &v); /* v is junk. */
            continue;
        }
        OBJ_DROP_PROPERTY(cx, obj2, prop);
#endif

        if (!OBJ_SET_PROPERTY(cx, obj, id, &v2))
            return JS_FALSE;
        if (!OBJ_SET_PROPERTY(cx, obj, id2, &v))
            return JS_FALSE;
    }

    *rval = OBJECT_TO_JSVAL(obj);
    return JS_TRUE;
}

typedef struct HSortArgs {
    void         *vec;
    size_t       elsize;
    void         *pivot;
    JSComparator cmp;
    void         *arg;
    JSBool       fastcopy;
} HSortArgs;

static int
sort_compare(const void *a, const void *b, void *arg);

static int
sort_compare_strings(const void *a, const void *b, void *arg);

static void
HeapSortHelper(JSBool building, HSortArgs *hsa, size_t lo, size_t hi)
{
    void *pivot, *vec, *vec2, *arg, *a, *b;
    size_t elsize;
    JSComparator cmp;
    JSBool fastcopy;
    size_t j, hiDiv2;

    pivot = hsa->pivot;
    vec = hsa->vec;
    elsize = hsa->elsize;
    vec2 =  (char *)vec - 2 * elsize;
    cmp = hsa->cmp;
    arg = hsa->arg;

    fastcopy = hsa->fastcopy;
#define MEMCPY(p,q,n) \
    (fastcopy ? (void)(*(jsval*)(p) = *(jsval*)(q)) : (void)memcpy(p, q, n))

    if (lo == 1) {
        j = 2;
        b = (char *)vec + elsize;
        if (j < hi && cmp(vec, b, arg) < 0)
            j++;
        a = (char *)vec + (hi - 1) * elsize;
        b = (char *)vec2 + j * elsize;

        /* 
         * During sorting phase b points to a member of heap that cannot be
         * bigger then biggest of vec[0] and vec[1], and cmp(a, b, arg) <= 0
         * always holds.
         */
        if ((building || hi == 2) && cmp(a, b, arg) >= 0)
            return;

        MEMCPY(pivot, a, elsize);
        MEMCPY(a, b, elsize);
        lo = j;
    } else {
        a = (char *)vec2 + lo * elsize;
        MEMCPY(pivot, a, elsize);
    }

    hiDiv2 = hi/2;
    while (lo <= hiDiv2) {
        j = lo + lo;
        a = (char *)vec2 + j * elsize;
        b = (char *)vec + (j - 1) * elsize;
        if (j < hi && cmp(a, b, arg) < 0)
            j++;
        b = (char *)vec2 + j * elsize;
        if (cmp(pivot, b, arg) >= 0)
            break;

        a = (char *)vec2 + lo * elsize;
        MEMCPY(a, b, elsize);
        lo = j;
    }

    a = (char *)vec2 + lo * elsize;
    MEMCPY(a, pivot, elsize);
#undef MEMCPY
}

JSBool
js_HeapSort(void *vec, size_t nel, size_t elsize, JSComparator cmp, void *arg) 
{
    void *pivot;
    HSortArgs hsa;
    size_t i;

    pivot = malloc(elsize);
    if (!pivot)
        return JS_FALSE;
    hsa.vec = vec;
    hsa.elsize = elsize;
    hsa.pivot = pivot;
    hsa.cmp = cmp;
    hsa.arg = arg;
    hsa.fastcopy = (cmp == sort_compare || cmp == sort_compare_strings);

    for (i = nel/2; i != 0; i--)
        HeapSortHelper(JS_TRUE, &hsa, i, nel);
    while (nel > 2)
        HeapSortHelper(JS_FALSE, &hsa, 1, --nel);

    free(pivot);
    return JS_TRUE;
}

typedef struct CompareArgs {
    JSContext  *context;
    jsval      fval;
    JSBool     status;
} CompareArgs;

static int
sort_compare(const void *a, const void *b, void *arg)
{
    jsval av = *(const jsval *)a, bv = *(const jsval *)b;
    CompareArgs *ca = (CompareArgs *) arg;
    JSContext *cx = ca->context;
    jsdouble cmp = -1;
    jsval fval, argv[2], rval;
    JSBool ok;

    fval = ca->fval;
    if (fval == JSVAL_NULL) {
        JSString *astr, *bstr;

        if (av == bv) {
            cmp = 0;
        } else if (av == JSVAL_VOID || bv == JSVAL_VOID) {
            /* Put undefined properties at the end. */
            cmp = (av == JSVAL_VOID) ? 1 : -1;
        } else if ((astr = js_ValueToString(cx, av)) != NULL &&
                   (bstr = js_ValueToString(cx, bv)) != NULL) {
            cmp = js_CompareStrings(astr, bstr);
        } else {
            ca->status = JS_FALSE;
        }
    } else {
        argv[0] = av;
        argv[1] = bv;
        ok = js_InternalCall(cx,
                             OBJ_GET_PARENT(cx, JSVAL_TO_OBJECT(fval)),
                             fval, 2, argv, &rval);
        if (ok) {
            ok = js_ValueToNumber(cx, rval, &cmp);
            /* Clamp cmp to -1, 0, 1. */
            if (JSDOUBLE_IS_NaN(cmp)) {
                /* XXX report some kind of error here?  ECMA talks about
                 * 'consistent compare functions' that don't return NaN, but is
                 * silent about what the result should be.  So we currently
                 * ignore it.
                 */
                cmp = 0;
            } else if (cmp > 0) {
                cmp = 1; 
	    } else if (cmp < 0) {
		cmp = -1;
	    } else {
		cmp = 0;
            }
        } else {
            ca->status = ok;
        }
    }
    return (int)cmp;
}

static int
sort_compare_strings(const void *a, const void *b, void *arg)
{
    jsval av = *(const jsval *)a, bv = *(const jsval *)b;

    return (int) js_CompareStrings(JSVAL_TO_STRING(av), JSVAL_TO_STRING(bv));
}

/* XXXmccabe do the sort helper functions need to take int?  (Or can we claim
 * that 2^32 * 32 is too large to worry about?)  Something dumps when I change
 * to unsigned int; is qsort using -1 as a fencepost?
 */
static JSBool
array_sort(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    jsval fval;
    CompareArgs ca;
    jsuint len, newlen, i;
    jsval *vec;
    jsid id;
    size_t nbytes;

    /*
     * Optimize the default compare function case if all of obj's elements
     * have values of type string.
     */
    JSBool all_strings;

    if (argc > 0) {
        if (JSVAL_IS_PRIMITIVE(argv[0])) {
            JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
                                 JSMSG_BAD_SORT_ARG);
            return JS_FALSE;
        }
        fval = argv[0];
        all_strings = JS_FALSE; /* non-default compare function */
    } else {
        fval = JSVAL_NULL;
        all_strings = JS_TRUE;  /* check for all string values */
    }

    if (!js_GetLengthProperty(cx, obj, &len))
        return JS_FALSE;
    if (len == 0) {
        *rval = OBJECT_TO_JSVAL(obj);
        return JS_TRUE;
    }

    /*
     * Test for size_t overflow, which could lead to indexing beyond the end
     * of the malloc'd vector.
     */
    nbytes = len * sizeof(jsval);
    if ((double) nbytes < (double) len * sizeof(jsval)) {
        JS_ReportOutOfMemory(cx);
        return JS_FALSE;
    }
    vec = (jsval *) JS_malloc(cx, nbytes);
    if (!vec)
        return JS_FALSE;

#if JS_HAS_SPARSE_ARRAYS
    newlen = 0;
#else
    newlen = len;
#endif

    for (i = 0; i < len; i++) {
        ca.status = IndexToId(cx, i, &id);
        if (!ca.status)
            goto out;
#if JS_HAS_SPARSE_ARRAYS
        {
            JSObject *obj2;
            JSProperty *prop;
            ca.status = OBJ_LOOKUP_PROPERTY(cx, obj, id, &obj2, &prop);
            if (!ca.status)
                goto out;
            if (!prop) {
                vec[i] = JSVAL_VOID;
                continue;
            }
            OBJ_DROP_PROPERTY(cx, obj2, prop);
            newlen++;
        }
#endif
        ca.status = OBJ_GET_PROPERTY(cx, obj, id, &vec[i]);
        if (!ca.status)
            goto out;

        /* We know JSVAL_IS_STRING yields 0 or 1, so avoid a branch via &=. */
        all_strings &= JSVAL_IS_STRING(vec[i]); 
    }

    ca.context = cx;
    ca.fval = fval;
    ca.status = JS_TRUE;
    if (!js_HeapSort(vec, (size_t) len, sizeof(jsval),
                     all_strings ? sort_compare_strings : sort_compare,
                     &ca)) {
        JS_ReportOutOfMemory(cx);
        ca.status = JS_FALSE;
    }

    if (ca.status) {
        ca.status = InitArrayElements(cx, obj, newlen, vec);
        if (ca.status)
            *rval = OBJECT_TO_JSVAL(obj);
#if JS_HAS_SPARSE_ARRAYS
        /* set length of newly-created array object to old length. */
        if (ca.status && newlen < len) {
            ca.status = js_SetLengthProperty(cx, obj, len);

            /* Delete any leftover properties greater than newlen. */
            while (ca.status && newlen < len) {
                jsval junk;

                ca.status = !IndexToId(cx, newlen, &id) ||
                    !OBJ_DELETE_PROPERTY(cx, obj, id, &junk);
                newlen++;
            }
        }
#endif
    }

out:
    if (vec)
        JS_free(cx, vec);
    return ca.status;
}
#endif /* JS_HAS_SOME_PERL_FUN */

#if JS_HAS_MORE_PERL_FUN
/*
 * Perl-inspired push, pop, shift, unshift, and splice methods.
 */
static JSBool
array_push(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    jsuint length;
    uintN i;
    jsid id;

    if (!js_GetLengthProperty(cx, obj, &length))
        return JS_FALSE;
    for (i = 0; i < argc; i++) {
        if (!IndexToId(cx, length + i, &id))
            return JS_FALSE;
        if (!OBJ_SET_PROPERTY(cx, obj, id, &argv[i]))
            return JS_FALSE;
    }

    /*
     * If JS1.2, follow Perl4 by returning the last thing pushed.  Otherwise,
     * return the new array length.
     */
    length += argc;
    if (cx->version == JSVERSION_1_2) {
        *rval = argc ? argv[argc-1] : JSVAL_VOID;
    } else {
        if (!IndexToValue(cx, length, rval))
            return JS_FALSE;
    }
    return js_SetLengthProperty(cx, obj, length);