memory_mode_t
- class memory_mode_t
Data type holding the memory modes available to client programs.
Regarding these various memory-modes:
In no case shall the HarfBuzz client modify memory that is passed to HarfBuzz in a blob. If there is any such possibility,
HB_MEMORY_MODE_DUPLICATE
should be used such that HarfBuzz makes a copy immediately,Use
HB_MEMORY_MODE_READONLY
otherwise, unless you really really really know what you are doing,HB_MEMORY_MODE_WRITABLE
is appropriate if you really made a copy of data solely for the purpose of passing to HarfBuzz and doing that just once (no reuse!),If the font is mmap()ed, it’s okay to use
HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE
, however, using that mode correctly is very tricky. UseHB_MEMORY_MODE_READONLY
instead.
Fields
- class memory_mode_t
- DUPLICATE
HarfBuzz immediately makes a copy of the data.
- READONLY
HarfBuzz client will never modify the data, and HarfBuzz will never modify the data.
- READONLY_MAY_MAKE_WRITABLE
See above
- WRITABLE
HarfBuzz client made a copy of the data solely for HarfBuzz, so HarfBuzz may modify the data.