cmd/cgo: could we add a C.CBytes function?

[jbardin]

Would it be possible to add func C.Cbytes([]byte) unsafe.Pointer to the cgo package?

I have copied the C.CString function, minus the added 0 byte a couple times, and this seems like it could be a useful addition. Granted it's only 3 lines to do the malloc and copy, but this would also serve as documentation for users needing to copy data into C.

[ianlancetaylor]

Want to send in a CL?

[jbardin]

Sure, though I'm not quite as sure what to do with the cPrologGccgo. Should I use __go_open_array? Something like this:

void *_cgoPREFIX_Cfunc_CBytes(struct __go_open_array b) {
    char *p = malloc(b.__count);
    memmove(p, b.__data, b.__count);
    return p;
}

[ianlancetaylor]

Yes.

[gopherbot]

CL https://golang.org/cl/20762 mentions this issue.