Add two new fields, `cblifetime` and `cbcount`, to the `closure` type in generator/API.ml*. `cblifetime` tells if the closure may only be used for as long as the command is in flight or if the closure may be used until the handle is destructed. `cbcount` tells whether the closure may be called many times or just once.
This information is needed in the Rust bindings for: a) Knowing if the closure trait should be `FnMut` or `FnOnce` (see <https://doc.rust-lang.org/std/ops/trait.FnOnce.html>). b) Knowing for what lifetime the closure should be valid. A closure that may be called after the function invokation has returned must live for the `'static` lietime. But static closures are inconveniant for the user since they can't effectively borrow any local data. So it is good if this restriction is relaxed when it is not needed. --- generator/API.ml | 20 ++++++++++++++++++++ generator/API.mli | 17 +++++++++++++++++ 2 files changed, 37 insertions(+) diff --git a/generator/API.ml b/generator/API.ml index f90a6fa..42b9eec 100644 --- a/generator/API.ml +++ b/generator/API.ml @@ -77,6 +77,8 @@ and ret = and closure = { cbname : string; cbargs : cbarg list; + cblifetime : cblifetime; + cbcount : cbcount } and cbarg = | CBArrayAndLen of arg * string @@ -87,6 +89,12 @@ and cbarg = | CBString of string | CBUInt of string | CBUInt64 of string +and cblifetime = +| CBCommand +| CBHandle +and cbcount = +| CBOnce +| CBMany and enum = { enum_prefix : string; enums : (string * int) list @@ -141,20 +149,28 @@ the handle from the NBD protocol handshake." (* Closures. *) let chunk_closure = { cbname = "chunk"; + cblifetime = CBCommand; + cbcount = CBMany; cbargs = [ CBBytesIn ("subbuf", "count"); CBUInt64 "offset"; CBUInt "status"; CBMutable (Int "error") ] } let completion_closure = { cbname = "completion"; + cblifetime = CBCommand; + cbcount = CBOnce; cbargs = [ CBMutable (Int "error") ] } let debug_closure = { cbname = "debug"; + cblifetime = CBHandle; + cbcount = CBMany; cbargs = [ CBString "context"; CBString "msg" ] } let extent_closure = { cbname = "extent"; + cblifetime = CBCommand; + cbcount = CBMany; cbargs = [ CBString "metacontext"; CBUInt64 "offset"; CBArrayAndLen (UInt32 "entries", @@ -163,10 +179,14 @@ let extent_closure = { } let list_closure = { cbname = "list"; + cblifetime = CBCommand; + cbcount = CBMany; cbargs = [ CBString "name"; CBString "description" ] } let context_closure = { cbname = "context"; + cblifetime = CBCommand; + cbcount = CBMany; cbargs = [ CBString "name" ] } let all_closures = [ chunk_closure; completion_closure; diff --git a/generator/API.mli b/generator/API.mli index 361132d..ff85849 100644 --- a/generator/API.mli +++ b/generator/API.mli @@ -94,6 +94,12 @@ and ret = and closure = { cbname : string; (** name of callback function *) cbargs : cbarg list; (** all closures return int for now *) + (** An upper bound of the lifetime of the closure. Either it will be used for + as long as the command is in flight or it may be used until the handle + is destructed. *) + cblifetime : cblifetime; + (** Whether the callback may only be called once or many times. *) + cbcount : cbcount; } and cbarg = | CBArrayAndLen of arg * string (** array + number of entries *) @@ -104,6 +110,17 @@ and cbarg = | CBString of string (** like String *) | CBUInt of string (** like UInt *) | CBUInt64 of string (** like UInt64 *) +and cblifetime = +| CBCommand (** The closure may only be used until the command is retired. + (E.G., completion callback or list callback.) *) +| CBHandle (** The closure might be used until the handle is descructed. + (E.G., debug callback.) *) +and cbcount = +| CBOnce (** The closure will be used 0 or 1 time if the aio_* call returned an + error and exactly once if the call succeeded. + (E.g., completion callback.) *) +| CBMany (** The closure may be used any number of times. + (E.g., list callback.) *) and enum = { enum_prefix : string; (** prefix of each enum variant *) enums : (string * int) list (** enum names and their values in C *) -- 2.41.0 _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
