inline std::size_t LinkView::size() const noexcept
{
    REALM_ASSERT(is_attached());

    if (!m_row_indexes.is_attached())
        return 0;

    return m_row_indexes.size();
}

inline bool InterprocessMutex::is_valid() noexcept
{
#ifdef REALM_ROBUST_MUTEX_EMULATION
    return true;
#else
    REALM_ASSERT(m_shared_part);
    return m_shared_part->is_valid();
#endif
}

inline void StringColumn::insert(std::size_t row_ndx, StringData value)
{
    REALM_ASSERT(!(value.is_null() && !m_nullable));
    std::size_t size = this->size();
    REALM_ASSERT_3(row_ndx, <=, size);
    std::size_t num_rows = 1;
    bool is_append = row_ndx == size;
    do_insert(row_ndx, value, num_rows, is_append); // Throws
}

void SyncFileActionMetadata::remove()
{
    REALM_ASSERT(m_realm);
    m_realm->verify_thread();
    m_realm->begin_transaction();
    TableRef table = ObjectStore::table_for_object_type(m_realm->read_group(), c_sync_fileActionMetadata);
    table->move_last_over(m_row.get_index());
    m_realm->commit_transaction();
    m_realm = nullptr;
}

 void set_null(size_t index) override
 {
     REALM_ASSERT(m_nullable);
     if (!m_array->is_inner_bptree_node()) {
         static_cast<BasicArray<T>*>(m_array.get())->set(index, null::get_null_float<T>()); // Throws
         return;
     }
     SetLeafElem set_leaf_elem(m_array->get_alloc(), null::get_null_float<T>());
     m_array->update_bptree_elem(index, set_leaf_elem); // Throws
 }

// Implementing pure virtual method of ColumnBase.
inline void StringColumn::insert_rows(size_t row_ndx, size_t num_rows_to_insert,
                                      size_t prior_num_rows)
{
    REALM_ASSERT_DEBUG(prior_num_rows == size());
    REALM_ASSERT(row_ndx <= prior_num_rows);

    StringData value = m_nullable ? realm::null() : StringData("");
    bool is_append = (row_ndx == prior_num_rows);
    do_insert(row_ndx, value, num_rows_to_insert, is_append); // Throws
}

// Old database files will not have the m_nulls array, so we need code paths for
// backwards compatibility for these cases. We can test if m_nulls exists by looking
// at number of references in this ArrayBinary.
inline bool ArrayBinary::legacy_array_type() const noexcept
{
    if (Array::size() == 3)
        return false; // New database file
    else if (Array::size() == 2)
        return true; // Old database file
    else
        REALM_ASSERT(false); // Should never happen
    return false;
}

inline void InterprocessMutex::lock()
{
#ifdef REALM_ROBUST_MUTEX_EMULATION
    std::unique_lock<Mutex> mutex_lock(m_lock_info->m_local_mutex);
    m_lock_info->m_file.lock_exclusive();
    mutex_lock.release();
#else
    REALM_ASSERT(m_shared_part);
    m_shared_part->lock([]() {});
#endif
}

inline void Spec::set_column_attr(size_t column_ndx, ColumnAttr attr)
{
    REALM_ASSERT(column_ndx < get_column_count());

    // At this point we only allow one attr at a time
    // so setting it will overwrite existing. In the future
    // we will allow combinations.
    m_attr.set(column_ndx, attr);

    update_has_strong_link_columns();
}

inline void BinaryColumn::update_from_parent(size_t old_baseline) noexcept
{
    if (root_is_leaf()) {
        bool is_big = m_array->get_context_flag();
        if (!is_big) {
            // Small blobs root leaf
            REALM_ASSERT(dynamic_cast<ArrayBinary*>(m_array.get()));
            ArrayBinary* leaf = static_cast<ArrayBinary*>(m_array.get());
            leaf->update_from_parent(old_baseline);
            return;
        }
        // Big blobs root leaf
        REALM_ASSERT(dynamic_cast<ArrayBigBlobs*>(m_array.get()));
        ArrayBigBlobs* leaf = static_cast<ArrayBigBlobs*>(m_array.get());
        leaf->update_from_parent(old_baseline);
        return;
    }
    // Non-leaf root
    m_array->update_from_parent(old_baseline);
}

inline size_t Utf8x16<Char16, Traits16>::find_utf8_buf_size(const Char16*& in_begin,
                                                                 const Char16* const in_end)
{
        size_t num_out = 0;
    const Char16* in = in_begin;
    while (in != in_end) {
        REALM_ASSERT(&in[0] >= in_begin && &in[0] < in_end);
        uint_fast16_t v = uint_fast16_t(Traits16::to_int_type(in[0]));
        if (REALM_LIKELY(v < 0x80)) {
            if (REALM_UNLIKELY(int_add_with_overflow_detect(num_out, 1)))
                break; // Avoid overflow
            in += 1;
        }
        else if (REALM_LIKELY(v < 0x800)) {
            if (REALM_UNLIKELY(int_add_with_overflow_detect(num_out, 2)))
                break; // Avoid overflow
            in += 1;
        }
        else if (REALM_LIKELY(v < 0xD800 || 0xE000 <= v)) {
            if (REALM_UNLIKELY(int_add_with_overflow_detect(num_out, 3)))
                break; // Avoid overflow
            in += 1;
        }
        else {
            if (REALM_UNLIKELY(in + 1 == in_end)) {
                break; // Incomplete surrogate pair
            }
            if (REALM_UNLIKELY(int_add_with_overflow_detect(num_out, 4)))
                break; // Avoid overflow
            in += 2;
        }
    }
    REALM_ASSERT(in >= in_begin && in <= in_end);
    in_begin  = in;
    return num_out;
}

        void init(RowIndexes* row_indexes)
        {
            m_columns.clear();
            m_string_enum_columns.clear();
            m_columns.resize(m_column_indexes.size(), 0);
            m_string_enum_columns.resize(m_column_indexes.size(), 0);

            for (size_t i = 0; i < m_column_indexes.size(); i++) {
                const ColumnBase& cb = row_indexes->get_column_base(m_column_indexes[i]);
                const ColumnTemplateBase* ctb = dynamic_cast<const ColumnTemplateBase*>(&cb);
                REALM_ASSERT(ctb);
                if (const StringEnumColumn* cse = dynamic_cast<const StringEnumColumn*>(&cb))
                    m_string_enum_columns[i] = cse;
                else
                    m_columns[i] = ctb;
            }
        }

MemRef BasicArray<T>::slice(size_t offset, size_t size, Allocator& target_alloc) const
{
    REALM_ASSERT(is_attached());

    // FIXME: This can be optimized as a single contiguous copy
    // operation.
    BasicArray slice(target_alloc);
    _impl::ShallowArrayDestroyGuard dg(&slice);
    slice.create(); // Throws
    size_t begin = offset;
    size_t end   = offset + size;
    for (size_t i = begin; i != end; ++i) {
        T value = get(i);
        slice.add(value); // Throws
    }
    dg.release();
    return slice.get_mem();
}

ValueType Object::get_property_value_impl(ContextType& ctx, const Property &property)
{
    verify_attached();

    size_t column = property.table_column;
    if (is_nullable(property.type) && m_row.is_null(column)) {
        return ctx.null_value();
    }

    if (is_array(property.type) && property.type != PropertyType::LinkingObjects) {
        REALM_ASSERT(property.type == PropertyType::Object);
        return ctx.box(List(m_realm, m_row.get_linklist(column)));
    }

    switch (property.type & ~PropertyType::Flags) {
        case PropertyType::Bool:   return ctx.box(m_row.get_bool(column));
        case PropertyType::Int:    return ctx.box(m_row.get_int(column));
        case PropertyType::Float:  return ctx.box(m_row.get_float(column));
        case PropertyType::Double: return ctx.box(m_row.get_double(column));
        case PropertyType::String: return ctx.box(m_row.get_string(column));
        case PropertyType::Data:   return ctx.box(m_row.get_binary(column));
        case PropertyType::Date:   return ctx.box(m_row.get_timestamp(column));
        case PropertyType::Any:    return ctx.box(m_row.get_mixed(column));
        case PropertyType::Object: {
            auto linkObjectSchema = m_realm->schema().find(property.object_type);
            TableRef table = ObjectStore::table_for_object_type(m_realm->read_group(), property.object_type);
            return ctx.box(Object(m_realm, *linkObjectSchema, table->get(m_row.get_link(column))));
        }
        case PropertyType::LinkingObjects: {
            auto target_object_schema = m_realm->schema().find(property.object_type);
            auto link_property = target_object_schema->property_for_name(property.link_origin_property_name);
            TableRef table = ObjectStore::table_for_object_type(m_realm->read_group(), target_object_schema->name);
            auto tv = m_row.get_table()->get_backlink_view(m_row.get_index(), table.get(), link_property->table_column);
            return ctx.box(Results(m_realm, std::move(tv)));
        }
        default: REALM_UNREACHABLE();
    }
}

inline bool Descriptor::operator==(const Descriptor& d) const noexcept
{
    REALM_ASSERT(is_attached());
    REALM_ASSERT(d.is_attached());
    return *m_spec == *d.m_spec;
}

 template <class T> T& get_as()
 {
     REALM_ASSERT(type == GetInstructionType<T>::value);
     return *reinterpret_cast<T*>(&m_storage);
 }

inline bool Utf8x16<Char16, Traits16>::to_utf16(const char*& in_begin, const char* const in_end, Char16*& out_begin,
                                                Char16* const out_end)
{
    typedef std::char_traits<char> traits8;
    bool invalid = false;
    const char* in = in_begin;
    Char16* out = out_begin;
    while (in != in_end) {
        if (REALM_UNLIKELY(out == out_end)) {
            break; // Need space in output buffer
        }
        REALM_ASSERT(&in[0] >= in_begin && &in[0] < in_end);
        uint_fast16_t v1 = uint_fast16_t(traits8::to_int_type(in[0]));
        if (REALM_LIKELY(v1 < 0x80)) { // One byte
            // UTF-8 layout: 0xxxxxxx
            *out++ = Traits16::to_char_type(v1);
            in += 1;
            continue;
        }
        if (REALM_UNLIKELY(v1 < 0xC0)) {
            invalid = true;
            break; // Invalid first byte of UTF-8 sequence
        }
        if (REALM_LIKELY(v1 < 0xE0)) { // Two bytes
            if (REALM_UNLIKELY(in_end - in < 2)) {
                invalid = true;
                break; // Incomplete UTF-8 sequence
            }
            REALM_ASSERT(&in[1] >= in_begin && &in[1] < in_end);
            uint_fast16_t v2 = uint_fast16_t(traits8::to_int_type(in[1]));
            // UTF-8 layout: 110xxxxx 10xxxxxx
            if (REALM_UNLIKELY((v2 & 0xC0) != 0x80)) {
                invalid = true;
                break; // Invalid continuation byte
            }
            uint_fast16_t v = uint_fast16_t(((v1 & 0x1F) << 6) | ((v2 & 0x3F) << 0));
            if (REALM_UNLIKELY(v < 0x80)) {
                invalid = true;
                break; // Overlong encoding is invalid
            }
            *out++ = Traits16::to_char_type(v);
            in += 2;
            continue;
        }
        if (REALM_LIKELY(v1 < 0xF0)) { // Three bytes
            if (REALM_UNLIKELY(in_end - in < 3)) {
                invalid = true;
                break; // Incomplete UTF-8 sequence
            }
            REALM_ASSERT(&in[1] >= in_begin && &in[2] < in_end);
            uint_fast16_t v2 = uint_fast16_t(traits8::to_int_type(in[1]));
            uint_fast16_t v3 = uint_fast16_t(traits8::to_int_type(in[2]));
            // UTF-8 layout: 1110xxxx 10xxxxxx 10xxxxxx
            if (REALM_UNLIKELY((v2 & 0xC0) != 0x80 || (v3 & 0xC0) != 0x80)) {
                invalid = true;
                break; // Invalid continuation byte
            }
            uint_fast16_t v = uint_fast16_t(((v1 & 0x0F) << 12) | ((v2 & 0x3F) << 6) | ((v3 & 0x3F) << 0));
            if (REALM_UNLIKELY(v < 0x800)) {
                invalid = true;
                break; // Overlong encoding is invalid
            }
            if (REALM_UNLIKELY(0xD800 <= v && v < 0xE000)) {
                invalid = true;
                break; // Illegal code point range (reserved for UTF-16 surrogate pairs)
            }
            *out++ = Traits16::to_char_type(v);
            in += 3;
            continue;
        }
        if (REALM_UNLIKELY(out + 1 == out_end)) {
            break; // Need space in output buffer for surrogate pair
        }
        if (REALM_LIKELY(v1 < 0xF8)) { // Four bytes
            if (REALM_UNLIKELY(in_end - in < 4)) {
                invalid = true;
                break; // Incomplete UTF-8 sequence
            }
            uint_fast32_t w1 = uint_fast32_t(v1); // 16 bit -> 32 bit
            REALM_ASSERT(&in[1] >= in_begin && &in[3] < in_end);
            uint_fast32_t v2 = uint_fast32_t(traits8::to_int_type(in[1])); // 32 bit intended
            uint_fast16_t v3 = uint_fast16_t(traits8::to_int_type(in[2])); // 16 bit intended
            uint_fast16_t v4 = uint_fast16_t(traits8::to_int_type(in[3])); // 16 bit intended
            // UTF-8 layout: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
            if (REALM_UNLIKELY((v2 & 0xC0) != 0x80 || (v3 & 0xC0) != 0x80 || (v4 & 0xC0) != 0x80)) {
                invalid = true;
                break; // Invalid continuation byte
            }
            uint_fast32_t v = uint_fast32_t(((w1 & 0x07) << 18) | // Parenthesis is 32 bit partial result
                                            ((v2 & 0x3F) << 12) | // Parenthesis is 32 bit partial result
                                            ((v3 & 0x3F) << 6) |  // Parenthesis is 16 bit partial result
                                            ((v4 & 0x3F) << 0));  // Parenthesis is 16 bit partial result
            if (REALM_UNLIKELY(v < 0x10000)) {
                invalid = true;
                break; // Overlong encoding is invalid
            }
            if (REALM_UNLIKELY(0x110000 <= v)) {
                invalid = true;
                break; // Code point too big for UTF-16
            }
//.........这里部分代码省略.........

template <class A, class B, class C, class D> bool operator()(A, B, C, D) const { REALM_ASSERT(false); return false; }