similar to: [PATCH libnbd v2 0/5] lib: Implement closure lifetimes.

This implements most of what I wrote here: https://www.redhat.com/archives/libguestfs/2019-July/msg00213.html

These are some simplifications to the generator. They don't probably make much sense on their own, but they are preparatory to better handling of enums, and or'd lists of flags. Rich.

I think I've addressed everything that was raised in review. Some of the highlights: - Callbacks should be freed reliably along all exit paths. - There's a simple test of closure lifetimes. - I've tried to use VALID|FREE in all the places where I'm confident that it's safe and correct to do. There may be more places. Note this is an optimization and shouldn't

As before, but this one has working Python bindings. OCaml still TBD. Rich.

Patches 1-4 are basically uncontroversial, straightforward refactoring and IMHO we should just push them. Possibly 1-3 should be squashed together, but I posted them separately so they are easier to review. Patches 5 and 6 together implement OClosure. Patch 5 adds the feature and is simple to understand. Patch 6 changes the Closure completion callbacks into OClosure, but because it doesn't

Posting now that I got something to compile (at the expense of breaking OCaml bindings), but I'm open to ideas on how to improve it. Eric Blake (2): generator: Tweak print_c_arg_list to take alternate first arg RFC: generator: Handle shared callbacks in Python generator/generator | 556 ++++++++++++++++++++++---------------------- 1 file changed, 280 insertions(+), 276 deletions(-) --

Patches 1 & 2 are rather complex, but the end result is that we pass closures + user_data + free function in single struct parameters as I described previously in this email: https://www.redhat.com/archives/libguestfs/2019-August/msg00210.html Patch 3 adds a convenient FREE_CALLBACK macro which seems a worthwhile simplification if you buy into 1 & 2. Patch 4 adds another macro which is

As proposed here: https://www.redhat.com/archives/libguestfs/2019-August/msg00130.html I didn't actually read Eric's replies to that yet because I've been concentrating on writing these patches all day. Anyway here they are and I'll look at what Eric said about the proposal next. Rich.

On 7/24/19 7:17 AM, Richard W.M. Jones wrote: > In preparation for closure lifetimes, split up the Closure so it no > longer describes a list of closures, but a single callback. > > This changes the API because functions which take 2 or more closures > now pass a separate user_data for each one. > --- > docs/libnbd.pod | 3 +- >

** INCOMPLETE ** This is the generator change as discussed on the list already. The Python and OCaml bindings are not yet done. It passes all [C only] tests and valgrind. Note that nbd_add_close_callback is inconsistent with other closure types because it passes the user_data parameter after the function. (This is not caused by the current patch, it was already inconsistent). We decided that

On 7/24/19 7:17 AM, Richard W.M. Jones wrote: > Previously closures had a crude flag which tells if they are > persistent or transient. Transient closures (flag = false) last for > the lifetime of the currently called libnbd function. Persistent > closures had an indefinite lifetime which could last for as long as > the handle. In language bindings handling persistent closures

Basically the same as this patch series, but for Python: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html plus adding the 590 asynch test at the end. Rich.

This is a combination of these two earlier series: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html https://www.redhat.com/archives/libguestfs/2019-August/msg00240.html plus changes to allow .callback = NULL / .free != NULL, and to reduce the complexity of freeing callbacks. Although it's rather long there's nothing complex here. We might consider squashing some

On 7/16/19 6:04 AM, Richard W.M. Jones wrote: > A Closure is a list of (usually one, but can be more) closures. In C > there is also a singe ‘void *user_data’ parameter which is passed by > the caller into the function and through as the first parameter of > each callback invocation. > > By grouping the previously separate Opaque and Callback* parameters > together we can

In this patch series we use the newly introduced free callback on the completion function to dererence the OCaml NBD.Buffer. I will make the same kind of change for Python later in a separate series. The completion function is always called at the C level, even if the OCaml program didn't use the optional argument. That's because the free callback doesn't run otherwise. There is a

This largish series adds several new features to the generator. Enum maps to enumerated types (like enum in C). The only current use for this is replacing the nbd_set_tls (nbd, 0/1/2) parameter with LIBNBD_TLS_DISABLE, LIBNBD_TLS_ALLOW, LIBNBD_TLS_REQUIRE (and natural equivalents in other programming languages). Flags maps to any uint32_t bitmask. It is basically a non-optional, generalized

Previously closures had a crude flag which tells if they are persistent or transient. Transient closures (flag = false) last for the lifetime of the currently called libnbd function. Persistent closures had an indefinite lifetime which could last for as long as the handle. In language bindings handling persistent closures was wasteful as we needed to register a "close callback" to

v1 was here: https://www.redhat.com/archives/libguestfs/2019-August/msg00168.html I pushed uncontroversial patches 1-4 v2: - The implementation of OClosure (new patch 1) in Python is fixed. - Patch 2 (old patch 5) is unchanged. - I added a new API for removing debug callbacks. I think this approach has some advantages over using OClosure. - I didn't yet do any work on changing the

I've mentioned this topic before (in fact, the idea of adding NBD_CMD_FLAG_DF was first mentioned at [1]), but finally finished enough of an implementation to feel confident in posting it. I'd still like to add something under examples/ that uses the new API to implement strict checking of a server's structured replies read implementation (ensure that a server never sends data after

In preparation for closure lifetimes, split up the Closure so it no longer describes a list of closures, but a single callback. This changes the API because functions which take 2 or more closures now pass a separate user_data for each one. --- docs/libnbd.pod | 3 +- examples/strict-structured-reads.c | 2 +- generator/generator | 760