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Oleg Vazhnev
Oleg Vazhnev

Reputation: 24067

how to use "c-style flags enum" from c++ code?

ef_vi_alloc_from_pd function from this c code accepts enum as last argument:

int ef_vi_alloc_from_pd(ef_vi* vi, ef_driver_handle vi_dh,
            struct ef_pd* pd, ef_driver_handle pd_dh,
            int evq_capacity, int rxq_capacity, int txq_capacity,
            ef_vi* evq_opt, ef_driver_handle evq_dh,
            enum ef_vi_flags flags)

In this c example we define flags as unsigned vi_flags and it works:

  unsigned vi_flags;
  vi_flags = EF_VI_FLAGS_DEFAULT;
  if( cfg_timestamping )
    vi_flags |= EF_VI_RX_TIMESTAMPS;
  TRY(ef_vi_alloc_from_pd(&res->vi, res->dh, &res->pd, res->dh,
                          -1, -1, 0, NULL, -1, vi_flags));

But in c++ it doesn't work, I have compile error when calling ef_vi_alloc_from_pd error: invalid conversion from ‘unsigned int’ to ‘ef_vi_flags’ [-fpermissive]

I've tried to define vi_flags as enum:

enum ef_vi_flags vi_flags;
vi_flags = EF_VI_FLAGS_DEFAULT;
vi_flags |= EF_VI_RX_TIMESTAMPS;

But this doesn't compile too, when I doing "|=" error: invalid conversion from ‘int’ to ‘ef_vi_flags’ [-fpermissive]

How to use ef_vi_alloc_from_pd from c++?

Upvotes: 0

Views: 273

Answers (1)

Jarod42
Jarod42

Reputation: 218278

You may do:

ef_vi_flags vi_flags = ef_vi_flags(EF_VI_FLAGS_DEFAULT | EF_VI_RX_TIMESTAMPS);

Upvotes: 2

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