On Fri, 22 Apr 2022 17:51:46 -0400 Kent Overstreet <kent.overstreet@xxxxxxxxx> wrote: > > But it's definitely not an unreasonable idea - I can try it out and see how it > turns out. Would you have any objections to making some changes to seq_buf? No I don't mind, and that's why I want the coupled, as enhancements or bug fixes would happen to both. > > - You've got size and len as size_t, I've got them as unsigned. Given that we > need to be checking for overflow anyways for correctens, I like having them > as u32s. I had it as size_t as I had planned (and still plan to) make seq_file use seq_buf, and seq_file uses size_t. Who knows, perhaps in the future, we may have strings that are more than 4GBs. ;-) > - seq_buf->readpos - it looks like this is only used by seq_buf_to_user(), does > it need to be in seq_buf? Perhaps. > - in printbufs, I make sure the buffer is always nul-terminated - seems > simplest, given that we need to make sure there's always room for the > terminating nul anyways. I'm not against that. It was an optimization, but I never actually benchmarked it. But I'm not sure how many fast paths it is used in to warrant that kind of optimization over the complexity it can bring for users. > > A downside of having printbuf on top of seq_buf is that now we've got two apis > that functions can output to - vs. if we modified printbuf by adding a flag for > "this is an external buffer, don't reallocate it". That approach would be less > code overall, for sure. > > Could I get you to look over printbuf and share your thoughts on the different > approaches? Sure, but will have to wait till next week. -- Steve
