diff options
Diffstat (limited to 'src/corelib/tools/qarraydata.h')
| -rw-r--r-- | src/corelib/tools/qarraydata.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/src/corelib/tools/qarraydata.h b/src/corelib/tools/qarraydata.h index babccc6017..8c21fd55c8 100644 --- a/src/corelib/tools/qarraydata.h +++ b/src/corelib/tools/qarraydata.h @@ -56,6 +56,7 @@ struct Q_CORE_EXPORT QArrayData CapacityReserved = 0x0010, //!< the capacity was reserved by the user, try to keep it GrowsForward = 0x0020, //!< allocate with eyes towards growing through append() GrowsBackwards = 0x0040, //!< allocate with eyes towards growing through prepend() + Mutable = 0x0080, //!< the data can be changed; doesn't say anything about the header /// this option is used by the Q_ARRAY_LITERAL and similar macros StaticDataFlags = RawDataType, @@ -102,7 +103,16 @@ struct Q_CORE_EXPORT QArrayData // follow COW principles. bool isMutable() const { - return flags & AllocatedDataType; + return flags & Mutable; + } + + // Returns true if a detach is necessary before modifying the data + // This method is intentionally not const: if you want to know whether + // detaching is necessary, you should be in a non-const function already + bool needsDetach() + { + // ### optimize me -- this currently requires 3 conditionals! + return !isMutable() || ref.isShared(); } size_t detachCapacity(size_t newSize) const |