On Wed, Aug 02, 2023 at 12:40:46PM +0000, Tage Johansson wrote: It looks as if rust-bindgen isn't in fact being used (as you removed it, per the cover letter). There's just one mention of it in a comment. So I think this paragraph should be removed from the commit message. By the way we don't tend to use markup in the commit messages (although I suppose github/gitlab will understand it). I have no particular strong preference about this, but it's not standard. So I think earlier we found that this wasn't sufficient to make rust actually work: https://listman.redhat.com/archives/libguestfs/2023-July/032121.html How about adding back the test that the compiler can build binaries from an earlier version? We have to cope with the environment we find. We don't control the many and varied environments that libnbd is compiled in. We can't have a situation like the one in the email above where ./configure passes but compilation then breaks. [...] If there's no possible error, don't need to use a Result<> wrapper. Looks sensible. I don't know if I mentioned this one before, and TBH it's a matter of your preference, but is using '(arg : arg)' (ie. declaring the named parameter 'arg' to have type 'arg') necessary? My editor tells me the type of OCaml expressions if I select them and use C-c C-t, and even if it didn't here it's pretty obvious what the type is. Excess comma (',') in the OCaml comment here? Here we're using markdown, I guess, but ocamldoc comments prefer to use [ ... ] instead of ` ... ` (although we don't use ocamldoc really). This is what replaces rust-bindgen? If you wanted to (and it may or may not be a good idea) you could include the actual version of libnbd here. You'd need to move rust/Cargo.toml to rust/Cargo.toml.in and add an autoconf AC_CONFIG_FILES directive to near the end of configure.in. Seems like the dependencies are pretty light ... good! This is mostly all good, but I think you will need to add libnbd-sys/src/.keep to EXTRA_DIST. You can check by doing: make && make dist && make maintainer-check-extra-dist And I think this is now split up as requested before, so good too. This needs to be inside the if HAVE_RUST clause, since it requires $(CARGO) and the general test in ./configure that rust was OK. But this can stay outside since it just does a regular 'rm'. Although it's not a very big deal, it'd be better if @CARGO@ was used here. The reason is that you could in theory do something like: ./configure CARGO=/usr/bin/my-special-cargo but the tests would run just cargo (not /usr/bin/my-special-cargo) test. However getting there is tricky. You have to rename rust/run-tests.sh to rust/run-tests.sh.in, and then add that to AC_CONFIG_FILES in configure.ac. Also I wonder if this breaks bisection? Since there are no tests yet. [...] Interesting ... What's the Fatal/Recoverable distinction used for? ... I guess here, but what's this used for? I think this (Debug trait) explains why we're hiding the various debug calls, so that seems fine. "underlying" Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com nbdkit - Flexible, fast NBD server with plugins https://gitlab.com/nbdkit/nbdkit

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

On Wed, Aug 02, 2023 at 12:40:49PM +0000, Tage Johansson wrote: I think there's an extra ',' here. Previous comments about use of markdown apply too. I still feel we're overspecifying the interface in patches 2, 3 & 4, just to avoid using a reference count in the Rust bindings. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 100 libraries supported. http://fedoraproject.org/wiki/MinGW

A couple of integration tests are added in rust/tests. They are mostly ported from the OCaml tests. --- rust/Cargo.toml | 4 + rust/Makefile.am | 1 + rust/run-tests.sh | 6 +- rust/tests/nbdkit_pattern/mod.rs | 28 ++++ rust/tests/test_100_handle.rs | 25 ++++ rust/tests/test_110_defaults.rs | 33 +++++ rust/tests/test_120_set_non_defaults.rs | 53 +++++++ rust/tests/test_130_private_data.rs | 28 ++++ rust/tests/test_140_explicit_close.rs | 31 ++++ rust/tests/test_200_connect_command.rs | 32 ++++ rust/tests/test_210_opt_abort.rs | 31 ++++ rust/tests/test_220_opt_list.rs | 86 +++++++++++ rust/tests/test_230_opt_info.rs | 120 +++++++++++++++ rust/tests/test_240_opt_list_meta.rs | 147 +++++++++++++++++++ rust/tests/test_245_opt_list_meta_queries.rs | 93 ++++++++++++ rust/tests/test_250_opt_set_meta.rs | 123 ++++++++++++++++ rust/tests/test_255_opt_set_meta_queries.rs | 109 ++++++++++++++ rust/tests/test_300_get_size.rs | 35 +++++ rust/tests/test_400_pread.rs | 39 +++++ rust/tests/test_405_pread_structured.rs | 79 ++++++++++ rust/tests/test_410_pwrite.rs | 58 ++++++++ rust/tests/test_460_block_status.rs | 92 ++++++++++++ rust/tests/test_620_stats.rs | 75 ++++++++++ rust/tests/test_log/mod.rs | 86 +++++++++++ 24 files changed, 1412 insertions(+), 2 deletions(-) create mode 100644 rust/tests/nbdkit_pattern/mod.rs create mode 100644 rust/tests/test_100_handle.rs create mode 100644 rust/tests/test_110_defaults.rs create mode 100644 rust/tests/test_120_set_non_defaults.rs create mode 100644 rust/tests/test_130_private_data.rs create mode 100644 rust/tests/test_140_explicit_close.rs create mode 100644 rust/tests/test_200_connect_command.rs create mode 100644 rust/tests/test_210_opt_abort.rs create mode 100644 rust/tests/test_220_opt_list.rs create mode 100644 rust/tests/test_230_opt_info.rs create mode 100644 rust/tests/test_240_opt_list_meta.rs create mode 100644 rust/tests/test_245_opt_list_meta_queries.rs create mode 100644 rust/tests/test_250_opt_set_meta.rs create mode 100644 rust/tests/test_255_opt_set_meta_queries.rs create mode 100644 rust/tests/test_300_get_size.rs create mode 100644 rust/tests/test_400_pread.rs create mode 100644 rust/tests/test_405_pread_structured.rs create mode 100644 rust/tests/test_410_pwrite.rs create mode 100644 rust/tests/test_460_block_status.rs create mode 100644 rust/tests/test_620_stats.rs create mode 100644 rust/tests/test_log/mod.rs diff --git a/rust/Cargo.toml b/rust/Cargo.toml index e81360b..f74c3ac 100644 --- a/rust/Cargo.toml +++ b/rust/Cargo.toml @@ -48,3 +48,7 @@ byte-strings = "0.3.1" [features] default = ["log"] + +[dev-dependencies] +once_cell = "1.18.0" +tempfile = "3.6.0" diff --git a/rust/Makefile.am b/rust/Makefile.am index 5160e9e..251a139 100644 --- a/rust/Makefile.am +++ b/rust/Makefile.am @@ -58,6 +58,7 @@ TESTS_ENVIRONMENT = \ LIBNBD_DEBUG=1 \ $(MALLOC_CHECKS) \ abs_top_srcdir=$(abs_top_srcdir) \ + CARGO=$(CARGO) \ $(NULL) LOG_COMPILER = $(top_builddir)/run TESTS = run-tests.sh diff --git a/rust/run-tests.sh b/rust/run-tests.sh index 7a0bc85..005000e 100755 --- a/rust/run-tests.sh +++ b/rust/run-tests.sh @@ -1,6 +1,6 @@ #!/bin/bash - # nbd client library in userspace -# Copyright Red Hat +# Copyright Tage Johansson # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public @@ -21,4 +21,6 @@ set -e set -x -cargo test +requires nbdkit --version + +$CARGO test -- --nocapture diff --git a/rust/tests/nbdkit_pattern/mod.rs b/rust/tests/nbdkit_pattern/mod.rs new file mode 100644 index 0000000..5f4069e --- /dev/null +++ b/rust/tests/nbdkit_pattern/mod.rs @@ -0,0 +1,28 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +use once_cell::sync::Lazy; + +/// The byte pattern as described in nbdkit-PATTERN-plugin(1). +pub static PATTERN: Lazy<Vec<u8>> = Lazy::new(|| { + let mut pattern = Vec::with_capacity(512); + for i in 0u64..64 { + pattern.extend_from_slice((i * 8).to_be_bytes().as_slice()); + } + assert_eq!(pattern.len(), 512); + pattern +}); diff --git a/rust/tests/test_100_handle.rs b/rust/tests/test_100_handle.rs new file mode 100644 index 0000000..85e18aa --- /dev/null +++ b/rust/tests/test_100_handle.rs @@ -0,0 +1,25 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +//! Just check that we can link with libnbd and create a handle. + +#![deny(warnings)] + +#[test] +fn test_nbd_handle_new() { + let _ = libnbd::Handle::new().unwrap(); +} diff --git a/rust/tests/test_110_defaults.rs b/rust/tests/test_110_defaults.rs new file mode 100644 index 0000000..ac1e29c --- /dev/null +++ b/rust/tests/test_110_defaults.rs @@ -0,0 +1,33 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +#[test] +fn test_defaults() { + let nbd = libnbd::Handle::new().unwrap(); + + assert!(nbd.get_export_name().unwrap().is_empty()); + assert!(!nbd.get_full_info().unwrap()); + assert_eq!(nbd.get_tls(), libnbd::Tls::Disable); + assert!(nbd.get_request_structured_replies()); + assert!(nbd.get_request_meta_context().unwrap()); + assert!(nbd.get_request_block_size().unwrap()); + assert!(nbd.get_pread_initialize()); + assert!(nbd.get_handshake_flags().is_all()); + assert!(!nbd.get_opt_mode()); +} diff --git a/rust/tests/test_120_set_non_defaults.rs b/rust/tests/test_120_set_non_defaults.rs new file mode 100644 index 0000000..7f1edab --- /dev/null +++ b/rust/tests/test_120_set_non_defaults.rs @@ -0,0 +1,53 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +#[test] +fn test_set_non_defaults() { + let nbd = libnbd::Handle::new().unwrap(); + + nbd.set_export_name("name").unwrap(); + assert_eq!(nbd.get_export_name().unwrap(), b"name"); + + nbd.set_full_info(true).unwrap(); + assert!(nbd.get_full_info().unwrap()); + + if nbd.supports_tls() { + nbd.set_tls(libnbd::Tls::Allow).unwrap(); + assert_eq!(nbd.get_tls(), libnbd::Tls::Allow); + } + + nbd.set_request_structured_replies(false).unwrap(); + assert!(!nbd.get_request_structured_replies()); + + nbd.set_request_meta_context(false).unwrap(); + assert!(!nbd.get_request_meta_context().unwrap()); + + nbd.set_request_block_size(false).unwrap(); + assert!(!nbd.get_request_block_size().unwrap()); + + nbd.set_pread_initialize(false).unwrap(); + assert!(!nbd.get_pread_initialize()); + + nbd.set_handshake_flags(libnbd::HandshakeFlag::empty()) + .unwrap(); + assert!(nbd.get_handshake_flags().is_empty()); + + nbd.set_opt_mode(true).unwrap(); + assert!(nbd.get_opt_mode()); +} diff --git a/rust/tests/test_130_private_data.rs b/rust/tests/test_130_private_data.rs new file mode 100644 index 0000000..bb507fb --- /dev/null +++ b/rust/tests/test_130_private_data.rs @@ -0,0 +1,28 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +#[test] +fn test_private_data() { + let nbd = libnbd::Handle::new().unwrap(); + + assert_eq!(nbd.get_private_data(), 0); + assert_eq!(nbd.set_private_data(42), 0); + assert_eq!(nbd.set_private_data(314), 42); + assert_eq!(nbd.get_private_data(), 314); +} diff --git a/rust/tests/test_140_explicit_close.rs b/rust/tests/test_140_explicit_close.rs new file mode 100644 index 0000000..59ab382 --- /dev/null +++ b/rust/tests/test_140_explicit_close.rs @@ -0,0 +1,31 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +mod test_log; + +use test_log::DEBUG_LOGGER; + +#[test] +fn test_private_data() { + DEBUG_LOGGER.init(); + + let nbd = libnbd::Handle::new().unwrap(); + drop(nbd); + assert!(DEBUG_LOGGER.contains("closing handle")); +} diff --git a/rust/tests/test_200_connect_command.rs b/rust/tests/test_200_connect_command.rs new file mode 100644 index 0000000..8338650 --- /dev/null +++ b/rust/tests/test_200_connect_command.rs @@ -0,0 +1,32 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + + +#[test] +fn test_connect_command() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "null", + ]) + .unwrap(); +} diff --git a/rust/tests/test_210_opt_abort.rs b/rust/tests/test_210_opt_abort.rs new file mode 100644 index 0000000..c59805f --- /dev/null +++ b/rust/tests/test_210_opt_abort.rs @@ -0,0 +1,31 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +#[test] +fn test_opt_abort() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&["nbdkit", "-s", "--exit-with-parent", "-v", "null"]) + .unwrap(); + assert_eq!(nbd.get_protocol().unwrap(), b"newstyle-fixed"); + assert!(nbd.get_structured_replies_negotiated().unwrap()); + + nbd.opt_abort().unwrap(); + assert!(nbd.aio_is_closed()); +} diff --git a/rust/tests/test_220_opt_list.rs b/rust/tests/test_220_opt_list.rs new file mode 100644 index 0000000..180a95b --- /dev/null +++ b/rust/tests/test_220_opt_list.rs @@ -0,0 +1,86 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use std::env; +use std::os::unix::ffi::OsStringExt as _; +use std::path::Path; +use std::sync::Arc; +use std::sync::Mutex; + +/// Test different types of connections. +struct ConnTester { + script_path: String, +} + +impl ConnTester { + fn new() -> Self { + let srcdir = env::var("srcdir").unwrap(); + let srcdir = Path::new(&srcdir); + let script_path = srcdir.join("../tests/opt-list.sh"); + let script_path = + String::from_utf8(script_path.into_os_string().into_vec()).unwrap(); + Self { script_path } + } + + fn connect( + &self, + mode: u8, + expected_exports: &[&str], + ) -> libnbd::Result<()> { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "sh", + &self.script_path, + &format!("mode={mode}"), + ]) + .unwrap(); + + // Collect all exports in this list. + let exports = Arc::new(Mutex::new(Vec::new())); + let exports_clone = exports.clone(); + let count = nbd.opt_list(move |name, _| { + exports_clone + .lock() + .unwrap() + .push(String::from_utf8(name.to_owned()).unwrap()); + 0 + })?; + let exports = Arc::into_inner(exports).unwrap().into_inner().unwrap(); + assert_eq!(exports.len(), count as usize); + assert_eq!(exports.len(), expected_exports.len()); + for (export, &expected) in exports.iter().zip(expected_exports) { + assert_eq!(export, expected); + } + Ok(()) + } +} + +#[test] +fn test_opt_list() { + let conn_tester = ConnTester::new(); + assert!(conn_tester.connect(0, &[]).is_err()); + assert!(conn_tester.connect(1, &["a", "b"]).is_ok()); + assert!(conn_tester.connect(2, &[]).is_ok()); + assert!(conn_tester.connect(3, &["a"]).is_ok()); +} diff --git a/rust/tests/test_230_opt_info.rs b/rust/tests/test_230_opt_info.rs new file mode 100644 index 0000000..00e5fb0 --- /dev/null +++ b/rust/tests/test_230_opt_info.rs @@ -0,0 +1,120 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use libnbd::CONTEXT_BASE_ALLOCATION; +use std::env; +use std::path::Path; + +#[test] +fn test_opt_info() { + let srcdir = env::var("srcdir").unwrap(); + let srcdir = Path::new(&srcdir); + let script_path = srcdir.join("../tests/opt-info.sh"); + let script_path = script_path.to_str().unwrap(); + + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "sh", + script_path, + ]) + .unwrap(); + nbd.add_meta_context(CONTEXT_BASE_ALLOCATION).unwrap(); + + // No size, flags, or meta-contexts yet + assert!(nbd.get_size().is_err()); + assert!(nbd.is_read_only().is_err()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + + // info with no prior name gets info on "" + assert!(nbd.opt_info().is_ok()); + assert_eq!(nbd.get_size().unwrap(), 0); + assert!(nbd.is_read_only().unwrap()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // changing export wipes out prior info + nbd.set_export_name("b").unwrap(); + assert!(nbd.get_size().is_err()); + assert!(nbd.is_read_only().is_err()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + + // info on something not present fails + nbd.set_export_name("a").unwrap(); + assert!(nbd.opt_info().is_err()); + + // info for a different export, with automatic meta_context disabled + nbd.set_export_name("b").unwrap(); + nbd.set_request_meta_context(false).unwrap(); + nbd.opt_info().unwrap(); + // idempotent name change is no-op + nbd.set_export_name("b").unwrap(); + assert_eq!(nbd.get_size().unwrap(), 1); + assert!(!nbd.is_read_only().unwrap()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + nbd.set_request_meta_context(true).unwrap(); + + // go on something not present + nbd.set_export_name("a").unwrap(); + assert!(nbd.opt_go().is_err()); + assert!(nbd.get_size().is_err()); + assert!(nbd.is_read_only().is_err()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + + // go on a valid export + nbd.set_export_name("good").unwrap(); + nbd.opt_go().unwrap(); + assert_eq!(nbd.get_size().unwrap(), 4); + assert!(nbd.is_read_only().unwrap()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // now info is no longer valid, but does not wipe data + assert!(nbd.set_export_name("a").is_err()); + assert_eq!(nbd.get_export_name().unwrap(), b"good"); + assert!(nbd.opt_info().is_err()); + assert_eq!(nbd.get_size().unwrap(), 4); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + nbd.shutdown(None).unwrap(); + + // Another connection. This time, check that SET_META triggered by opt_info + // persists through nbd_opt_go with set_request_meta_context disabled. + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "sh", + &script_path, + ]) + .unwrap(); + nbd.add_meta_context("x-unexpected:bogus").unwrap(); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + nbd.opt_info().unwrap(); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + nbd.set_request_meta_context(false).unwrap(); + // Adding to the request list now won't matter + nbd.add_meta_context(CONTEXT_BASE_ALLOCATION).unwrap(); + nbd.opt_go().unwrap(); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); +} diff --git a/rust/tests/test_240_opt_list_meta.rs b/rust/tests/test_240_opt_list_meta.rs new file mode 100644 index 0000000..5598458 --- /dev/null +++ b/rust/tests/test_240_opt_list_meta.rs @@ -0,0 +1,147 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use std::sync::Arc; +use std::sync::Mutex; + +/// A struct with information about listed meta contexts. +#[derive(Debug, Clone, PartialEq, Eq)] +struct CtxInfo { + /// Whether the meta context "base:alloc" is listed. + has_alloc: bool, + /// The number of listed meta contexts. + count: u32, +} + +fn list_meta_ctxs(nbd: &libnbd::Handle) -> libnbd::Result<CtxInfo> { + let info = Arc::new(Mutex::new(CtxInfo { + has_alloc: false, + count: 0, + })); + let info_clone = info.clone(); + let replies = nbd.opt_list_meta_context(move |ctx| { + let mut info = info_clone.lock().unwrap(); + info.count += 1; + if ctx == libnbd::CONTEXT_BASE_ALLOCATION { + info.has_alloc = true; + } + 0 + })?; + let info = Arc::into_inner(info).unwrap().into_inner().unwrap(); + assert_eq!(info.count, replies); + Ok(info) +} + +#[test] +fn test_opt_list_meta() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "memory", + "size=1M", + ]) + .unwrap(); + + // First pass: empty query should give at least "base:allocation". + let info = list_meta_ctxs(&nbd).unwrap(); + assert!(info.count >= 1); + assert!(info.has_alloc); + let max = info.count; + + // Second pass: bogus query has no response. + nbd.add_meta_context("x-nosuch:").unwrap(); + assert_eq!( + list_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + + // Third pass: specific query should have one match. + nbd.add_meta_context("base:allocation").unwrap(); + assert_eq!(nbd.get_nr_meta_contexts().unwrap(), 2); + assert_eq!(nbd.get_meta_context(1).unwrap(), b"base:allocation"); + assert_eq!( + list_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 1, + has_alloc: true + } + ); + + // Fourth pass: opt_list_meta_context is stateless, so it should + // not wipe status learned during opt_info + assert!(nbd.can_meta_context("base:allocation").is_err()); + assert!(nbd.get_size().is_err()); + nbd.opt_info().unwrap(); + assert_eq!(nbd.get_size().unwrap(), 1048576); + assert!(nbd.can_meta_context("base:allocation").unwrap()); + nbd.clear_meta_contexts().unwrap(); + nbd.add_meta_context("x-nosuch:").unwrap(); + assert_eq!( + list_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + assert_eq!(nbd.get_size().unwrap(), 1048576); + assert!(nbd.can_meta_context("base:allocation").unwrap()); + + // Final pass: "base:" query should get at least "base:allocation" + nbd.add_meta_context("base:").unwrap(); + let info = list_meta_ctxs(&nbd).unwrap(); + assert!(info.count >= 1); + assert!(info.count <= max); + assert!(info.has_alloc); + + // Repeat but this time without structured replies. Deal gracefully + // with older servers that don't allow the attempt. + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.set_request_structured_replies(false).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "memory", + "size=1M", + ]) + .unwrap(); + let bytes = nbd.stats_bytes_sent(); + if let Ok(info) = list_meta_ctxs(&nbd) { + assert!(info.count >= 1); + assert!(info.has_alloc) + } else { + assert!(nbd.stats_bytes_sent() > bytes); + // ignoring failure from old server + } + + // Now enable structured replies, and a retry should pass. + assert!(nbd.opt_structured_reply().unwrap()); + let info = list_meta_ctxs(&nbd).unwrap(); + assert!(info.count >= 1); + assert!(info.has_alloc); +} diff --git a/rust/tests/test_245_opt_list_meta_queries.rs b/rust/tests/test_245_opt_list_meta_queries.rs new file mode 100644 index 0000000..da5c674 --- /dev/null +++ b/rust/tests/test_245_opt_list_meta_queries.rs @@ -0,0 +1,93 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use std::sync::Arc; +use std::sync::Mutex; + +/// A struct with information about listed meta contexts. +#[derive(Debug, Clone, PartialEq, Eq)] +struct CtxInfo { + /// Whether the meta context "base:allocation" is listed. + has_alloc: bool, + /// The number of listed meta contexts. + count: u32, +} + +fn list_meta_ctxs( + nbd: &libnbd::Handle, + queries: &[&[u8]], +) -> libnbd::Result<CtxInfo> { + let info = Arc::new(Mutex::new(CtxInfo { + has_alloc: false, + count: 0, + })); + let info_clone = info.clone(); + let replies = nbd.opt_list_meta_context_queries(queries, move |ctx| { + let mut info = info_clone.lock().unwrap(); + info.count += 1; + if ctx == libnbd::CONTEXT_BASE_ALLOCATION { + info.has_alloc = true; + } + 0 + })?; + let info = Arc::into_inner(info).unwrap().into_inner().unwrap(); + assert_eq!(info.count, replies); + Ok(info) +} + +#[test] +fn test_opt_list_meta_queries() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "memory", + "size=1M", + ]) + .unwrap(); + + // First pass: empty query should give at least "base:allocation". + nbd.add_meta_context("x-nosuch:").unwrap(); + let info = list_meta_ctxs(&nbd, &[]).unwrap(); + assert!(info.count >= 1); + assert!(info.has_alloc); + + // Second pass: bogus query has no response. + nbd.clear_meta_contexts().unwrap(); + assert_eq!( + list_meta_ctxs(&nbd, &[b"x-nosuch:"]).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + + // Third pass: specific query should have one match. + assert_eq!( + list_meta_ctxs(&nbd, &[b"x-nosuch:", libnbd::CONTEXT_BASE_ALLOCATION]) + .unwrap(), + CtxInfo { + count: 1, + has_alloc: true + } + ); +} diff --git a/rust/tests/test_250_opt_set_meta.rs b/rust/tests/test_250_opt_set_meta.rs new file mode 100644 index 0000000..c7a8144 --- /dev/null +++ b/rust/tests/test_250_opt_set_meta.rs @@ -0,0 +1,123 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use libnbd::CONTEXT_BASE_ALLOCATION; +use std::sync::Arc; +use std::sync::Mutex; + +/// A struct with information about set meta contexts. +#[derive(Debug, Clone, PartialEq, Eq)] +struct CtxInfo { + /// Whether the meta context "base:allocation" is set. + has_alloc: bool, + /// The number of set meta contexts. + count: u32, +} + +fn set_meta_ctxs(nbd: &libnbd::Handle) -> libnbd::Result<CtxInfo> { + let info = Arc::new(Mutex::new(CtxInfo { + has_alloc: false, + count: 0, + })); + let info_clone = info.clone(); + let replies = nbd.opt_set_meta_context(move |ctx| { + let mut info = info_clone.lock().unwrap(); + info.count += 1; + if ctx == CONTEXT_BASE_ALLOCATION { + info.has_alloc = true; + } + 0 + })?; + let info = Arc::into_inner(info).unwrap().into_inner().unwrap(); + assert_eq!(info.count, replies); + Ok(info) +} + +#[test] +fn test_opt_set_meta() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.set_request_structured_replies(false).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "memory", + "size=1M", + ]) + .unwrap(); + + // No contexts negotiated yet; can_meta should be error if any requested + assert!(!nbd.get_structured_replies_negotiated().unwrap()); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + nbd.add_meta_context(CONTEXT_BASE_ALLOCATION).unwrap(); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + + // SET cannot succeed until SR is negotiated. + assert!(nbd.opt_structured_reply().unwrap()); + assert!(nbd.get_structured_replies_negotiated().unwrap()); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).is_err()); + + // nbdkit does not match wildcard for SET, even though it does for LIST + nbd.clear_meta_contexts().unwrap(); + nbd.add_meta_context("base:").unwrap(); + assert_eq!( + set_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Negotiating with no contexts is not an error, but selects nothing + nbd.clear_meta_contexts().unwrap(); + assert_eq!( + set_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + + // Request 2 with expectation of 1; with set_request_meta_context off + nbd.add_meta_context("x-nosuch:context").unwrap(); + nbd.add_meta_context(CONTEXT_BASE_ALLOCATION).unwrap(); + nbd.set_request_meta_context(false).unwrap(); + assert_eq!( + set_meta_ctxs(&nbd).unwrap(), + CtxInfo { + count: 1, + has_alloc: true + } + ); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Transition to transmission phase; our last set should remain active + nbd.clear_meta_contexts().unwrap(); + nbd.add_meta_context("x-nosuch:context").unwrap(); + nbd.opt_go().unwrap(); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Now too late to set; but should not lose earlier state + assert!(set_meta_ctxs(&nbd).is_err()); + assert_eq!(nbd.get_size().unwrap(), 1048576); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); +} diff --git a/rust/tests/test_255_opt_set_meta_queries.rs b/rust/tests/test_255_opt_set_meta_queries.rs new file mode 100644 index 0000000..143a2f1 --- /dev/null +++ b/rust/tests/test_255_opt_set_meta_queries.rs @@ -0,0 +1,109 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use libnbd::CONTEXT_BASE_ALLOCATION; +use std::sync::Arc; +use std::sync::Mutex; + +/// A struct with information about set meta contexts. +#[derive(Debug, Clone, PartialEq, Eq)] +struct CtxInfo { + /// Whether the meta context "base:allocation" is set. + has_alloc: bool, + /// The number of set meta contexts. + count: u32, +} + +fn set_meta_ctxs_queries( + nbd: &libnbd::Handle, + queries: &[impl AsRef<[u8]>], +) -> libnbd::Result<CtxInfo> { + let info = Arc::new(Mutex::new(CtxInfo { + has_alloc: false, + count: 0, + })); + let info_clone = info.clone(); + let replies = nbd.opt_set_meta_context_queries(queries, move |ctx| { + let mut info = info_clone.lock().unwrap(); + info.count += 1; + if ctx == CONTEXT_BASE_ALLOCATION { + info.has_alloc = true; + } + 0 + })?; + let info = Arc::into_inner(info).unwrap().into_inner().unwrap(); + assert_eq!(info.count, replies); + Ok(info) +} + +#[test] +fn test_opt_set_meta_queries() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.set_opt_mode(true).unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "memory", + "size=1M", + ]) + .unwrap(); + + // nbdkit does not match wildcard for SET, even though it does for LIST + assert_eq!( + set_meta_ctxs_queries(&nbd, &["base:"]).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Negotiating with no contexts is not an error, but selects nothing + // An explicit empty list overrides a non-empty implicit list. + nbd.add_meta_context(CONTEXT_BASE_ALLOCATION).unwrap(); + assert_eq!( + set_meta_ctxs_queries(&nbd, &[] as &[&str]).unwrap(), + CtxInfo { + count: 0, + has_alloc: false + } + ); + assert!(!nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Request 2 with expectation of 1. + assert_eq!( + set_meta_ctxs_queries( + &nbd, + &[b"x-nosuch:context".as_slice(), CONTEXT_BASE_ALLOCATION] + ) + .unwrap(), + CtxInfo { + count: 1, + has_alloc: true + } + ); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); + + // Transition to transmission phase; our last set should remain active + nbd.set_request_meta_context(false).unwrap(); + nbd.opt_go().unwrap(); + assert!(nbd.can_meta_context(CONTEXT_BASE_ALLOCATION).unwrap()); +} diff --git a/rust/tests/test_300_get_size.rs b/rust/tests/test_300_get_size.rs new file mode 100644 index 0000000..c830164 --- /dev/null +++ b/rust/tests/test_300_get_size.rs @@ -0,0 +1,35 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + + +#[test] +fn test_get_size() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "null", + "size=1M", + ]) + .unwrap(); + + assert_eq!(nbd.get_size().unwrap(), 1048576); +} diff --git a/rust/tests/test_400_pread.rs b/rust/tests/test_400_pread.rs new file mode 100644 index 0000000..93b826c --- /dev/null +++ b/rust/tests/test_400_pread.rs @@ -0,0 +1,39 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +mod nbdkit_pattern; +use nbdkit_pattern::PATTERN; + +#[test] +fn test_pread() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "pattern", + "size=1M", + ]) + .unwrap(); + + let mut buf = [0; 512]; + nbd.pread(&mut buf, 0, None).unwrap(); + assert_eq!(buf.as_slice(), PATTERN.as_slice()); +} diff --git a/rust/tests/test_405_pread_structured.rs b/rust/tests/test_405_pread_structured.rs new file mode 100644 index 0000000..39a7fd5 --- /dev/null +++ b/rust/tests/test_405_pread_structured.rs @@ -0,0 +1,79 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +mod nbdkit_pattern; +use nbdkit_pattern::PATTERN; + +#[test] +fn test_pread_structured() { + let nbd = libnbd::Handle::new().unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "pattern", + "size=1M", + ]) + .unwrap(); + + fn f(buf: &[u8], offset: u64, s: u32, err: &mut i32) { + assert_eq!(*err, 0); + *err = 42; + assert_eq!(buf, PATTERN.as_slice()); + assert_eq!(offset, 0); + assert_eq!(s, libnbd::READ_DATA); + } + + let mut buf = [0; 512]; + nbd.pread_structured( + &mut buf, + 0, + |b, o, s, e| { + f(b, o, s, e); + 0 + }, + None, + ) + .unwrap(); + assert_eq!(buf.as_slice(), PATTERN.as_slice()); + + nbd.pread_structured( + &mut buf, + 0, + |b, o, s, e| { + f(b, o, s, e); + 0 + }, + Some(libnbd::CmdFlag::DF), + ) + .unwrap(); + assert_eq!(buf.as_slice(), PATTERN.as_slice()); + + let res = nbd.pread_structured( + &mut buf, + 0, + |b, o, s, e| { + f(b, o, s, e); + -1 + }, + Some(libnbd::CmdFlag::DF), + ); + assert_eq!(res.unwrap_err().errno(), Some(42)); +} diff --git a/rust/tests/test_410_pwrite.rs b/rust/tests/test_410_pwrite.rs new file mode 100644 index 0000000..d4d6b99 --- /dev/null +++ b/rust/tests/test_410_pwrite.rs @@ -0,0 +1,58 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use std::fs::{self, File}; + +#[test] +fn test_pwrite() { + let tmp_dir = tempfile::tempdir().unwrap(); + let data_file_path = tmp_dir.path().join("pwrite_test.data"); + let data_file = File::create(&data_file_path).unwrap(); + data_file.set_len(512).unwrap(); + drop(data_file); + let nbd = libnbd::Handle::new().unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "file", + data_file_path.to_str().unwrap(), + ]) + .unwrap(); + + let mut buf_1 = [0; 512]; + buf_1[10] = 0x01; + buf_1[510] = 0x55; + buf_1[511] = 0xAA; + + let flags = Some(libnbd::CmdFlag::FUA); + nbd.pwrite(&buf_1, 0, flags).unwrap(); + + let mut buf_2 = [0; 512]; + nbd.pread(&mut buf_2, 0, None).unwrap(); + + assert_eq!(buf_1, buf_2); + + // Drop nbd before tmp_dir is dropped. + drop(nbd); + + let data_file_content = fs::read(&data_file_path).unwrap(); + assert_eq!(buf_1.as_slice(), data_file_content.as_slice()); +} diff --git a/rust/tests/test_460_block_status.rs b/rust/tests/test_460_block_status.rs new file mode 100644 index 0000000..7cdcb34 --- /dev/null +++ b/rust/tests/test_460_block_status.rs @@ -0,0 +1,92 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + +use std::env; +use std::path::Path; +use std::sync::Arc; +use std::sync::Mutex; + +fn block_status_get_entries( + nbd: &libnbd::Handle, + count: u64, + offset: u64, + flags: Option<libnbd::CmdFlag>, +) -> Vec<u32> { + let entries = Arc::new(Mutex::new(None)); + let entries_clone = entries.clone(); + nbd.block_status( + count, + offset, + move |metacontext, _, entries, err| { + assert_eq!(*err, 0); + if metacontext == libnbd::CONTEXT_BASE_ALLOCATION { + *entries_clone.lock().unwrap() = Some(entries.to_vec()); + } + 0 + }, + flags, + ) + .unwrap(); + Arc::into_inner(entries) + .unwrap() + .into_inner() + .unwrap() + .unwrap() +} + +#[test] +fn test_block_status() { + let srcdir = env::var("srcdir").unwrap(); + let srcdir = Path::new(&srcdir); + let script_path = srcdir.join("../tests/meta-base-allocation.sh"); + let script_path = script_path.to_str().unwrap(); + let nbd = libnbd::Handle::new().unwrap(); + nbd.add_meta_context(libnbd::CONTEXT_BASE_ALLOCATION) + .unwrap(); + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "sh", + script_path, + ]) + .unwrap(); + + assert_eq!( + block_status_get_entries(&nbd, 65536, 0, None).as_slice(), + &[8192, 0, 8192, 1, 16384, 3, 16384, 2, 16384, 0,] + ); + + assert_eq!( + block_status_get_entries(&nbd, 1024, 32256, None).as_slice(), + &[512, 3, 16384, 2] + ); + + assert_eq!( + block_status_get_entries( + &nbd, + 1024, + 32256, + Some(libnbd::CmdFlag::REQ_ONE) + ) + .as_slice(), + &[512, 3] + ); +} diff --git a/rust/tests/test_620_stats.rs b/rust/tests/test_620_stats.rs new file mode 100644 index 0000000..134d59a --- /dev/null +++ b/rust/tests/test_620_stats.rs @@ -0,0 +1,75 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#![deny(warnings)] + + +#[test] +fn test_stats() { + let nbd = libnbd::Handle::new().unwrap(); + + // Pre-connection, stats start out at 0 + assert_eq!(nbd.stats_bytes_sent(), 0); + assert_eq!(nbd.stats_chunks_sent(), 0); + assert_eq!(nbd.stats_bytes_received(), 0); + assert_eq!(nbd.stats_chunks_received(), 0); + + // Connection performs handshaking, which increments stats. + // The number of bytes/chunks here may grow over time as more features get + // automatically negotiated, so merely check that they are non-zero. + nbd.connect_command(&[ + "nbdkit", + "-s", + "--exit-with-parent", + "-v", + "null", + ]) + .unwrap(); + + let bs1 = nbd.stats_bytes_sent(); + let cs1 = nbd.stats_chunks_sent(); + let br1 = nbd.stats_bytes_received(); + let cr1 = nbd.stats_chunks_received(); + assert!(cs1 > 0); + assert!(bs1 > cs1); + assert!(cr1 > 0); + assert!(br1 > cr1); + + // A flush command should be one chunk out, one chunk back (even if + // structured replies are in use) + nbd.flush(None).unwrap(); + let bs2 = nbd.stats_bytes_sent(); + let cs2 = nbd.stats_chunks_sent(); + let br2 = nbd.stats_bytes_received(); + let cr2 = nbd.stats_chunks_received(); + assert_eq!(bs2, bs1 + 28); + assert_eq!(cs2, cs1 + 1); + assert_eq!(br2, br1 + 16); // assumes nbdkit uses simple reply + assert_eq!(cr2, cr1 + 1); + + // Stats are still readable after the connection closes; we don't know if + // the server sent reply bytes to our NBD_CMD_DISC, so don't insist on it. + nbd.shutdown(None).unwrap(); + let bs3 = nbd.stats_bytes_sent(); + let cs3 = nbd.stats_chunks_sent(); + let br3 = nbd.stats_bytes_received(); + let cr3 = nbd.stats_chunks_received(); + assert!(bs3 > bs2); + assert_eq!(cs3, cs2 + 1); + assert!(br3 >= br2); + assert!(cr3 == cr2 || cr3 == cr2 + 1); +} diff --git a/rust/tests/test_log/mod.rs b/rust/tests/test_log/mod.rs new file mode 100644 index 0000000..8dbcd79 --- /dev/null +++ b/rust/tests/test_log/mod.rs @@ -0,0 +1,86 @@ +// libnbd Rust test case +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +//! This module provides facilities for capturing log output and asserting that +//! it does or does not contain certain messages. The primary use of this module +//! is to assert that certain libnbd operations are or are not performed. + +#![allow(unused)] + +use std::sync::Mutex; + +/// Logger that stores all debug messages in a list. +pub struct DebugLogger { + /// All targets and messages logged. Wrapped in a mutex so that it can be + /// updated with an imutable reference to self. + entries: Mutex<Vec<(String, String)>>, + is_initialized: Mutex<bool>, +} + +impl DebugLogger { + const fn new() -> Self { + Self { + entries: Mutex::new(Vec::new()), + is_initialized: Mutex::new(false), + } + } + + /// Set this logger as the global logger. + pub fn init(&'static self) { + let mut is_initialized = self.is_initialized.lock().unwrap(); + if !*is_initialized { + log::set_logger(self).unwrap(); + log::set_max_level(log::LevelFilter::Debug); + *is_initialized = true; + } + } + + /// Check wether a specific message has been logged. + pub fn contains(&self, msg: &str) -> bool { + self.entries.lock().unwrap().iter().any(|(_, x)| x == msg) + } + + /// Print all logged messages, in no particular order. + /// + /// Only for debug purposes. Remember to run cargo test with the `-- + /// --nocapture` arguments. That is, from the rust directory run: + /// `./../run cargo test -- --nocapture` + pub fn print_messages(&self) { + for (target, msg) in self.entries.lock().unwrap().iter() { + eprintln!("{target}: {msg}"); + } + } +} + +/// A static global `DebugLogger`. Just call `.init()` on this to set it as the +/// global logger. +pub static DEBUG_LOGGER: DebugLogger = DebugLogger::new(); + +impl log::Log for DebugLogger { + fn enabled(&self, metadata: &log::Metadata<'_>) -> bool { + metadata.level() == log::Level::Debug + } + + fn log(&self, record: &log::Record<'_>) { + self.entries + .lock() + .unwrap() + .push((record.target().to_string(), record.args().to_string())); + } + + fn flush(&self) {} +} -- 2.41.0

Make it possible to run Rust tests with Valgrind with `make check-valgrind` in the rust directory. --- rust/Makefile.am | 3 +++ rust/run-tests.sh | 6 +++++- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/rust/Makefile.am b/rust/Makefile.am index 251a139..19dbf02 100644 --- a/rust/Makefile.am +++ b/rust/Makefile.am @@ -63,6 +63,9 @@ TESTS_ENVIRONMENT = \ LOG_COMPILER = $(top_builddir)/run TESTS = run-tests.sh +check-valgrind: + LIBNBD_VALGRIND=1 $(MAKE) check + endif clean-local: diff --git a/rust/run-tests.sh b/rust/run-tests.sh index 005000e..da7852a 100755 --- a/rust/run-tests.sh +++ b/rust/run-tests.sh @@ -23,4 +23,8 @@ set -x requires nbdkit --version -$CARGO test -- --nocapture +if [ -z "$VG" ]; then + $CARGO test -- --nocapture +else + $CARGO test --config "target.'cfg(all())'.runner = \"$VG\"" -- --nocapture +fi -- 2.41.0

Create another handle type: `AsyncHandle`, which makes use of Rust's builtin asynchronous functions (see <https://doc.rust-lang.org/std/keyword.async.html>) and runs on top of the Tokio runtime (see <https://docs.rs/tokio>). For every asynchronous command, like `aio_connect()`, a corresponding `async` method is created on the handle. In this case it would be: async fn connect(...) -> Result<(), ...> When called, it will poll the file descriptor until the command is complete, and then return with a result. All the synchronous counterparts (like `nbd_connect()`) are excluded from this handle type as they are unnecessary and since they might interfear with the polling made by the Tokio runtime. For more details about how the asynchronous commands are executed, please see the comments in rust/src/async_handle.rs. --- generator/Rust.ml | 240 +++++++++++++++++++++++++++++++++++ generator/Rust.mli | 2 + generator/generator.ml | 1 + rust/Cargo.toml | 7 +- rust/Makefile.am | 2 + rust/src/async_handle.rs | 268 +++++++++++++++++++++++++++++++++++++++ rust/src/lib.rs | 8 ++ 7 files changed, 527 insertions(+), 1 deletion(-) create mode 100644 rust/src/async_handle.rs diff --git a/generator/Rust.ml b/generator/Rust.ml index d3225eb..dc82d46 100644 --- a/generator/Rust.ml +++ b/generator/Rust.ml @@ -558,3 +558,243 @@ let generate_rust_bindings () = pr "impl Handle {\n"; List.iter print_rust_handle_method handle_calls; pr "}\n\n" + +(*********************************************************) +(* The rest of the file conserns the asynchronous API. *) +(* *) +(* See the comments in rust/src/async_handle.rs for more *) +(* information about how it works. *) +(*********************************************************) + +let excluded_handle_calls : NameSet.t = + NameSet.of_list + [ + "aio_get_fd"; + "aio_get_direction"; + "aio_notify_read"; + "aio_notify_write"; + "clear_debug_callback"; + "get_debug"; + "poll"; + "poll2"; + "set_debug"; + "set_debug_callback"; + ] + +(* A mapping with names as keys. *) +module NameMap = Map.Make (String) + +(* Strip "aio_" from the beginning of a string. *) +let strip_aio name : string = + if String.starts_with ~prefix:"aio_" name then + String.sub name 4 (String.length name - 4) + else failwithf "Asynchronous call %s must begin with aio_" name + +(* A map with all asynchronous handle calls. The keys are names with "aio_" + stripped, the values are a tuple with the actual name (with "aio_"), the + [call] and the [async_kind]. *) +let async_handle_calls : ((string * call) * async_kind) NameMap.t = + handle_calls + |> List.filter (fun (n, _) -> not (NameSet.mem n excluded_handle_calls)) + |> List.filter_map (fun (name, call) -> + call.async_kind + |> Option.map (fun async_kind -> + (strip_aio name, ((name, call), async_kind)))) + |> List.to_seq |> NameMap.of_seq + +(* A mapping with all synchronous (not asynchronous) handle calls. Excluded + are also all synchronous calls that has an asynchronous counterpart. So if + "foo" is the name of a handle call and an asynchronous call "aio_foo" + exists, then "foo" will not b in this map. *) +let sync_handle_calls : call NameMap.t = + handle_calls + |> List.filter (fun (n, _) -> not (NameSet.mem n excluded_handle_calls)) + |> List.filter (fun (name, _) -> + (not (NameMap.mem name async_handle_calls)) + && not + (String.starts_with ~prefix:"aio_" name + && NameMap.mem (strip_aio name) async_handle_calls)) + |> List.to_seq |> NameMap.of_seq + +(* Get the Rust type for an argument in the asynchronous API. Like + [rust_arg_type] but no static lifetime on some closures and buffers. *) +let rust_async_arg_type : arg -> string = function + | Closure { cbargs; cbcount; cblifetime } -> + let lifetime = + match cblifetime with CBCommand -> None | CBHandle -> Some "'static" + in + "impl " ^ rust_closure_trait ~lifetime cbargs cbcount + | BytesPersistIn _ -> "&[u8]" + | BytesPersistOut _ -> "&mut [u8]" + | x -> rust_arg_type x + +(* Get the Rust type for an optional argument in the asynchronous API. Like + [rust_optarg_type] but no static lifetime on some closures. *) +let rust_async_optarg_type : optarg -> string = function + | OClosure x -> sprintf "Option<%s>" (rust_async_arg_type (Closure x)) + | x -> rust_optarg_type x + +(* A string of the argument list for a method on the handle, with both + mandotory and optional arguments. *) +let rust_async_handle_call_args { args; optargs } : string = + let rust_args_names = + List.map rust_arg_name args @ List.map rust_optarg_name optargs + and rust_args_types = + List.map rust_async_arg_type args + @ List.map rust_async_optarg_type optargs + in + String.concat ", " + (List.map2 (sprintf "%s: %s") rust_args_names rust_args_types) + +(* Print the Rust function for a not asynchronous handle call. *) +let print_rust_sync_handle_call (name : string) (call : call) = + print_rust_handle_call_comment call; + pr "pub fn %s(&self, %s) -> %s\n" name + (rust_async_handle_call_args call) + (rust_ret_type call); + print_ffi_call name "self.data.handle.handle" call; + pr "\n" + +(* Print the Rust function for an asynchronous handle call with a completion + callback. (Note that "callback" might be abbreviated with "cb" in the + following code. *) +let print_rust_async_handle_call_with_completion_cb name (aio_name, call) = + (* An array of all optional arguments. Useful because we need to deel with + the index of the completion callback. *) + let optargs = Array.of_list call.optargs in + (* The index of the completion callback in [optargs] *) + let completion_cb_index = + Array.find_map + (fun (i, optarg) -> + match optarg with + | OClosure { cbname } -> + if cbname = "completion" then Some i else None + | _ -> None) + (Array.mapi (fun x y -> (x, y)) optargs) + in + let completion_cb_index = + match completion_cb_index with + | Some x -> x + | None -> + failwithf + "The handle call %s is claimed to have a completion callback among \ + its optional arguments by the async_kind field, but so does not \ + seem to be the case." + aio_name + in + let optargs_before_completion_cb = + Array.to_list (Array.sub optargs 0 completion_cb_index) + and optargs_after_completion_cb = + Array.to_list + (Array.sub optargs (completion_cb_index + 1) + (Array.length optargs - (completion_cb_index + 1))) + in + (* All optional arguments excluding the completion callback. *) + let optargs_without_completion_cb = + optargs_before_completion_cb @ optargs_after_completion_cb + in + print_rust_handle_call_comment call; + pr "pub async fn %s(&self, %s) -> SharedResult<()> {\n" name + (rust_async_handle_call_args + { call with optargs = optargs_without_completion_cb }); + pr " // A oneshot channel to notify when the call is completed.\n"; + pr " let (ret_tx, ret_rx) = oneshot::channel::<SharedResult<()>>();\n"; + pr " let (ccb_tx, mut ccb_rx) = oneshot::channel::<c_int>();\n"; + (* Completion callback: *) + pr " let %s = Some(|err: &mut i32| {\n" + (rust_optarg_name (Array.get optargs completion_cb_index)); + pr " ccb_tx.send(*err).ok();\n"; + pr " 1\n"; + pr " });\n"; + (* End of completion callback. *) + print_ffi_call aio_name "self.data.handle.handle" call; + pr "?;\n"; + pr " let mut ret_tx = Some(ret_tx);\n"; + pr " let completion_predicate = \n"; + pr " move |_handle: &Handle, res: &SharedResult<()>| {\n"; + pr " let ret = if res.as_ref().is_err_and(|e| e.is_fatal()) {\n"; + pr " res.clone()\n"; + pr " } else {\n"; + pr " let Ok(errno) = ccb_rx.try_recv() else { return false; };\n"; + pr " if errno == 0 {\n"; + pr " Ok(())\n"; + pr " } else {\n"; + pr " if let Err(e) = res {\n"; + pr " Err(e.clone())\n"; + pr " } else {\n"; + pr " Err(Arc::new("; + pr " Error::Recoverable(ErrorKind::from_errno(errno))))\n"; + pr " }\n"; + pr " }\n"; + pr " };\n"; + pr " ret_tx.take().unwrap().send(ret).ok();\n"; + pr " true\n"; + pr " };\n"; + pr " self.add_command(completion_predicate)?;\n"; + pr " ret_rx.await.unwrap()\n"; + pr "}\n\n" + +(* Print a Rust function for an asynchronous handle call which signals + completion by changing state. The predicate is a call like + "aio_is_connecting" which should get the value (like false) for the call to + be complete. *) +let print_rust_async_handle_call_changing_state name (aio_name, call) + (predicate, value) = + let value = if value then "true" else "false" in + print_rust_handle_call_comment call; + pr "pub async fn %s(&self, %s) -> SharedResult<()>\n" name + (rust_async_handle_call_args call); + pr "{\n"; + print_ffi_call aio_name "self.data.handle.handle" call; + pr "?;\n"; + pr " let (ret_tx, ret_rx) = oneshot::channel::<SharedResult<()>>();\n"; + pr " let mut ret_tx = Some(ret_tx);\n"; + pr " let completion_predicate = \n"; + pr " move |handle: &Handle, res: &SharedResult<()>| {\n"; + pr " let ret = if let Err(_) = res {\n"; + pr " res.clone()\n"; + pr " } else {\n"; + pr " if handle.%s() != %s { return false; }\n" predicate value; + pr " else { Ok(()) }\n"; + pr " };\n"; + pr " ret_tx.take().unwrap().send(ret).ok();\n"; + pr " true\n"; + pr " };\n"; + pr " self.add_command(completion_predicate)?;\n"; + pr " ret_rx.await.unwrap()\n"; + pr "}\n\n" + +(* Print an impl with all handle calls. *) +let print_rust_async_handle_impls () = + pr "impl AsyncHandle {\n"; + NameMap.iter print_rust_sync_handle_call sync_handle_calls; + NameMap.iter + (fun name (call, async_kind) -> + match async_kind with + | WithCompletionCallback -> + print_rust_async_handle_call_with_completion_cb name call + | ChangesState (predicate, value) -> + print_rust_async_handle_call_changing_state name call + (predicate, value)) + async_handle_calls; + pr "}\n\n" + +let print_rust_async_imports () = + pr "use crate::{*, types::*};\n"; + pr "use os_str_bytes::OsStringBytes as _;\n"; + pr "use os_socketaddr::OsSocketAddr;\n"; + pr "use std::ffi::*;\n"; + pr "use std::mem;\n"; + pr "use std::net::SocketAddr;\n"; + pr "use std::os::fd::{AsRawFd, OwnedFd};\n"; + pr "use std::path::PathBuf;\n"; + pr "use std::ptr;\n"; + pr "use std::sync::Arc;\n"; + pr "use tokio::sync::oneshot;\n"; + pr "\n" + +let generate_rust_async_bindings () = + generate_header CStyle ~copyright:"Tage Johansson"; + pr "\n"; + print_rust_async_imports (); + print_rust_async_handle_impls () diff --git a/generator/Rust.mli b/generator/Rust.mli index 450e4ca..0960170 100644 --- a/generator/Rust.mli +++ b/generator/Rust.mli @@ -18,3 +18,5 @@ (* Print all flag-structs, enums, constants and handle calls in Rust code. *) val generate_rust_bindings : unit -> unit + +val generate_rust_async_bindings : unit -> unit diff --git a/generator/generator.ml b/generator/generator.ml index f5ef7cc..2118446 100644 --- a/generator/generator.ml +++ b/generator/generator.ml @@ -64,3 +64,4 @@ let () = output_to ~formatter:(Some Rustfmt) "rust/libnbd-sys/src/lib.rs" RustSys.generate_rust_sys_bindings; output_to ~formatter:(Some Rustfmt) "rust/src/bindings.rs" Rust.generate_rust_bindings; + output_to ~formatter:(Some Rustfmt) "rust/src/async_bindings.rs" Rust.generate_rust_async_bindings; diff --git a/rust/Cargo.toml b/rust/Cargo.toml index f74c3ac..c7e461a 100644 --- a/rust/Cargo.toml +++ b/rust/Cargo.toml @@ -45,10 +45,15 @@ thiserror = "1.0.40" log = { version = "0.4.19", optional = true } libc = "0.2.147" byte-strings = "0.3.1" +tokio = { optional = true, version = "1.29.1", default-features = false, features = ["rt", "sync", "net"] } +epoll = "4.3.3" [features] -default = ["log"] +default = ["log", "tokio"] [dev-dependencies] once_cell = "1.18.0" +pretty-hex = "0.3.0" +rand = { version = "0.8.5", default-features = false, features = ["small_rng", "min_const_gen"] } tempfile = "3.6.0" +tokio = { version = "1.29.1", default-features = false, features = ["macros", "rt-multi-thread"] } diff --git a/rust/Makefile.am b/rust/Makefile.am index 19dbf02..b954b22 100644 --- a/rust/Makefile.am +++ b/rust/Makefile.am @@ -19,6 +19,7 @@ include $(top_srcdir)/subdir-rules.mk generator_built = \ libnbd-sys/src/lib.rs \ + src/async_bindings.rs \ src/bindings.rs \ $(NULL) @@ -30,6 +31,7 @@ source_files = \ src/handle.rs \ src/types.rs \ src/utils.rs \ + src/async_handle.rs \ libnbd-sys/Cargo.toml \ libnbd-sys/build.rs \ $(NULL) diff --git a/rust/src/async_handle.rs b/rust/src/async_handle.rs new file mode 100644 index 0000000..4223b80 --- /dev/null +++ b/rust/src/async_handle.rs @@ -0,0 +1,268 @@ +// nbd client library in userspace +// Copyright Tage Johansson +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 2 of the License, or (at your option) any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +// This module implements an asynchronous handle working on top of the +// [Tokio](https://tokio.rs) runtime. When the handle is created, +// a "polling task" is spawned on the Tokio runtime. The purpose of that +// "polling task" is to call `aio_notify_*` when appropriate. It shares a +// reference to the handle as well as some other things with the handle in the +// [HandleData] struct. The "polling task" is sleeping when no command is in +// flight, but wakes up as soon as any command is issued. +// +// The commands are implemented as +// [`async fn`s](https://doc.rust-lang.org/std/keyword.async.html) +// in async_bindings.rs. When a new command is issued, it registers a +// completion predicate with [Handle::add_command]. That predicate takes a +// reference to the handle and should return [true] iff the command is complete. +// Whenever some work is performed in the polling task, the completion +// predicates for all pending commands are called. + +#![allow(unused_imports)] // XXX: remove this +use crate::sys; +use crate::Handle; +use crate::{Error, FatalErrorKind, Result}; +use crate::{AIO_DIRECTION_BOTH, AIO_DIRECTION_READ, AIO_DIRECTION_WRITE}; +use epoll::Events; +use std::sync::Arc; +use std::sync::Mutex; +use tokio::io::{unix::AsyncFd, Interest, Ready as IoReady}; +use tokio::sync::{broadcast, Notify}; +use tokio::task; + +/// A custom result type with a shared [crate::Error] as default error type. +pub type SharedResult<T, E = Arc<Error>> = Result<T, E>; + +/// An NBD handle using Rust's `async` functionality on top of the +/// [Tokio](https://docs.rs/tokio/) runtime. +pub struct AsyncHandle { + /// Data shared both by this struct and the polling task. + pub(crate) data: Arc<HandleData>, + + /// A task which soely purpose is to poll the NBD handle. + polling_task: tokio::task::AbortHandle, +} + +pub(crate) struct HandleData { + /// The underliing handle. + pub handle: Handle, + + /// A list of all pending commands. + /// + /// For every pending command (commands in flight), a predicate will be + /// stored in this list. Whenever some progress is made on the file + /// descriptor, the predicate is called with a reference to the handle + /// and a reference to the result of that call to `aio_notify_*`. + /// Iff the predicate returns [true], the command is considered completed + /// and removed from this list. + /// + /// If The polling task dies for some reason, this [SharedResult] will be + /// set to some error. + pub pending_commands: Mutex< + SharedResult< + Vec< + Box< + dyn FnMut(&Handle, &SharedResult<()>) -> bool + + Send + + Sync + + 'static, + >, + >, + >, + >, + + /// A notifier used by commands to notify the polling task when a new + /// asynchronous command is issued. + pub new_command: Notify, +} + +impl AsyncHandle { + pub fn new() -> Result<Self> { + let handle_data = Arc::new(HandleData { + handle: Handle::new()?, + pending_commands: Mutex::new(Ok(Vec::new())), + new_command: Notify::new(), + }); + + let handle_data_2 = handle_data.clone(); + let polling_task = task::spawn(async move { + // The polling task should never finish without an error. If the + // handle is dropped, the task is aborted so it'll not return in + // that case either. + let Err(err) = polling_task(&handle_data_2).await else { + unreachable!() + }; + let err = Arc::new(Error::Fatal(err)); + // Call the completion predicates for all pending commands with the + // error. + let mut pending_cmds = + handle_data_2.pending_commands.lock().unwrap(); + let res = Err(err); + for f in pending_cmds.as_mut().unwrap().iter_mut() { + f(&handle_data_2.handle, &res); + } + *pending_cmds = Err(res.unwrap_err()); + }) + .abort_handle(); + Ok(Self { + data: handle_data, + polling_task, + }) + } + + /// Get the underliing C pointer to the handle. + pub(crate) fn raw_handle(&self) -> *mut sys::nbd_handle { + self.data.handle.raw_handle() + } + + /// Call this method when a new command is issued. As argument is passed a + /// predicate which should return [true] iff the command is completed. + pub(crate) fn add_command( + &self, + mut completion_predicate: impl FnMut(&Handle, &SharedResult<()>) -> bool + + Send + + Sync + + 'static, + ) -> SharedResult<()> { + if !completion_predicate(&self.data.handle, &Ok(())) { + let mut pending_cmds_lock = + self.data.pending_commands.lock().unwrap(); + pending_cmds_lock + .as_mut() + .map_err(|e| e.clone())? + .push(Box::new(completion_predicate)); + self.data.new_command.notify_one(); + } + Ok(()) + } +} + +impl Drop for AsyncHandle { + fn drop(&mut self) { + self.polling_task.abort(); + } +} + +/// Get the read/write direction that the handle wants on the file descriptor. +fn get_fd_interest(handle: &Handle) -> Option<Interest> { + match handle.aio_get_direction() { + 0 => None, + AIO_DIRECTION_READ => Some(Interest::READABLE), + AIO_DIRECTION_WRITE => Some(Interest::WRITABLE), + AIO_DIRECTION_BOTH => Some(Interest::READABLE | Interest::WRITABLE), + _ => unreachable!(), + } +} + +/// A task that will run as long as the handle is alive. It will poll the +/// file descriptor when new data is availlable. +async fn polling_task(handle_data: &HandleData) -> Result<(), FatalErrorKind> { + let HandleData { + handle, + pending_commands, + new_command, + } = handle_data; + let fd = handle.aio_get_fd().map_err(Error::to_fatal)?; + // XXX: Might the file descriptor ever be changed? + let tokio_fd = AsyncFd::new(fd)?; + let epfd = epoll::create(false)?; + epoll::ctl( + epfd, + epoll::ControlOptions::EPOLL_CTL_ADD, + fd, + epoll::Event::new(Events::EPOLLIN | Events::EPOLLOUT, 42), + )?; + + // The following loop does approximately the following things: + // + // 1. Determine what Libnbd wants to do next on the file descriptor, + // (read/write/both/none), and store that in [fd_interest]. + // 2. Wait for either: + // a) That interest to be available on the file descriptor in which case: + // I. Call the correct `aio_notify_*` method. + // II. Execute step 1. + // III. Send the result of the call to `aio_notify_*` on + // [result_channel] to notify pending commands that some progress + // has been made. + // IV. Resume execution from step 2. + // b) A notification was received on [new_command] signaling that a new + // command was registered and that the intrest on the file descriptor + // might has changed. Resume execution from step 1. + loop { + let Some(fd_interest) = get_fd_interest(handle) else { + // The handle does not wait for any data of the file descriptor, + // so we wait until some command is issued. + new_command.notified().await; + continue; + }; + + if pending_commands + .lock() + .unwrap() + .as_ref() + .unwrap() + .is_empty() + { + // No command is pending so there is no point to do anything. + new_command.notified().await; + continue; + } + + // Wait for the requested interest to be available on the fd. + let mut ready_guard = tokio_fd.ready(fd_interest).await?; + let readyness = ready_guard.ready(); + let res = if readyness.is_readable() && fd_interest.is_readable() { + handle.aio_notify_read() + } else if readyness.is_writable() && fd_interest.is_writable() { + handle.aio_notify_write() + } else { + continue; + }; + let res = match res { + Ok(()) => Ok(()), + Err(e @ Error::Recoverable(_)) => Err(Arc::new(e)), + Err(Error::Fatal(e)) => return Err(e), + }; + + // Call the completion predicates of all pending commands. + let mut pending_cmds_lock = pending_commands.lock().unwrap(); + let pending_cmds = pending_cmds_lock.as_mut().unwrap(); + let mut i = 0; + while i < pending_cmds.len() { + if (pending_cmds[i])(handle, &res) { + let _ = pending_cmds.swap_remove(i); + } else { + i += 1; + } + } + drop(pending_cmds_lock); + + // Use epoll to check the current read/write availability on the fd. + // This is needed because Tokio does only support edge-triggered + // notifications but Libnbd requires level-triggered notifications. + let mut revent = epoll::Event { data: 0, events: 0 }; + // Setting timeout to 0 means that it will return immediately. + epoll::wait(epfd, 0, std::slice::from_mut(&mut revent))?; + let revents = Events::from_bits(revent.events).unwrap(); + if !revents.contains(Events::EPOLLIN) { + ready_guard.clear_ready_matching(IoReady::READABLE); + } + if !revents.contains(Events::EPOLLOUT) { + ready_guard.clear_ready_matching(IoReady::WRITABLE); + } + ready_guard.retain_ready(); + } +} diff --git a/rust/src/lib.rs b/rust/src/lib.rs index a6f3131..56316b4 100644 --- a/rust/src/lib.rs +++ b/rust/src/lib.rs @@ -17,11 +17,19 @@ #![deny(warnings)] +#[cfg(feature = "tokio")] +mod async_bindings; +#[cfg(feature = "tokio")] +mod async_handle; mod bindings; mod error; mod handle; pub mod types; mod utils; +#[cfg(feature = "tokio")] +pub use async_bindings::*; +#[cfg(feature = "tokio")] +pub use async_handle::{AsyncHandle, SharedResult}; pub use bindings::*; pub use error::{Error, ErrorKind, FatalErrorKind, Result}; pub use handle::Handle; -- 2.41.0

On Wed, Aug 02, 2023 at 12:40:53PM +0000, Tage Johansson wrote: Isn't this just saying that the call is synchronous? Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into KVM guests. http://libguestfs.org/virt-v2v

On Thu, Aug 03, 2023 at 03:30:36PM +0000, Tage Johansson wrote: No it'll be fine, thanks. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 100 libraries supported. http://fedoraproject.org/wiki/MinGW

On Wed, Aug 02, 2023 at 12:40:54PM +0000, Tage Johansson wrote: Reusing 'modifies_fd' as the variable containing a list of synchronous calls is a bit confusing. How about just using this code directly when creating the set, eg: NameSet.of_list ([ "aio_get_fd"; "aio_get_direction"; ... ] @ handle_calls |> List.filter (fun (_, { modifies_fd }) -> modifies_fd) |> List.map (fun (name, _) -> name) ) or using NameSet.union? Some of the code in the rest of this patch uses Set or Map sequences which don't work with OCaml 4.05 (RHEL 7). We're slowly dropping support for RHEL 7 so this is not necessarily a blocker, but if it was easy to change the code so it would still work that might be better. Everything must work with RHEL 8 (OCaml 4.07). Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 100 libraries supported. http://fedoraproject.org/wiki/MinGW

This patch adds a few examples in rust/examples/. The examples are compiled and run as part of the test suite. --- rust/Makefile.am | 3 + rust/examples/concurrent-read-write.rs | 135 +++++++++++++++++++++++++ rust/examples/connect-command.rs | 39 +++++++ rust/examples/fetch-first-sector.rs | 38 +++++++ rust/examples/get-size.rs | 29 ++++++ rust/run-tests.sh | 7 ++ 6 files changed, 251 insertions(+) create mode 100644 rust/examples/concurrent-read-write.rs create mode 100644 rust/examples/connect-command.rs create mode 100644 rust/examples/fetch-first-sector.rs create mode 100644 rust/examples/get-size.rs diff --git a/rust/Makefile.am b/rust/Makefile.am index b954b22..d75163d 100644 --- a/rust/Makefile.am +++ b/rust/Makefile.am @@ -32,6 +32,9 @@ source_files = \ src/types.rs \ src/utils.rs \ src/async_handle.rs \ + examples/connect-command.rs \ + examples/get-size.rs \ + examples/fetch-first-sector.rs \ libnbd-sys/Cargo.toml \ libnbd-sys/build.rs \ $(NULL) diff --git a/rust/examples/concurrent-read-write.rs b/rust/examples/concurrent-read-write.rs new file mode 100644 index 0000000..a1c3e8a --- /dev/null +++ b/rust/examples/concurrent-read-write.rs @@ -0,0 +1,135 @@ +//! Example usage with nbdkit: +//! +//! nbdkit -U - memory 100M \ +//! --run 'cargo run --example concurrent-read-write -- $unixsocket' +//! +//! This will read and write randomly over the first megabyte of the +//! plugin using multi-conn, multiple threads and multiple requests in +//! flight on each thread. + +#![deny(warnings)] +use rand::prelude::*; +use std::env; +use std::path::PathBuf; +use std::sync::Arc; +use tokio::task::JoinSet; + +/// Number of simultaneous connections to the NBD server. +/// +/// Note that some servers only support a limited number of +/// simultaneous connections, and/or have a configurable thread pool +/// internally, and if you exceed those limits then something will break. +const NR_MULTI_CONN: usize = 8; + +/// Number of commands that can be "in flight" at the same time on each +/// connection. (Therefore the total number of requests in flight may +/// be up to NR_MULTI_CONN * MAX_IN_FLIGHT). +const MAX_IN_FLIGHT: usize = 16; + +/// The size of large reads and writes, must be > 512. +const BUFFER_SIZE: usize = 1024; + +/// Number of commands we issue (per [task][tokio::task]). +const NR_CYCLES: usize = 32; + +/// Statistics gathered during the run. +#[derive(Debug, Default)] +struct Stats { + /// The total number of requests made. + requests: usize, +} + +#[tokio::main] +async fn main() -> anyhow::Result<()> { + let args = env::args_os().collect::<Vec<_>>(); + if args.len() != 2 { + anyhow::bail!("Usage: {:?} socket", args[0]); + } + let socket = &args[1]; + + // We begin by making a connection to the server to get the export size + // and ensure that it supports multiple connections and is writable. + let nbd = libnbd::Handle::new()?; + nbd.connect_unix(&socket)?; + let export_size = nbd.get_size()?; + anyhow::ensure!( + (BUFFER_SIZE as u64) < export_size, + "export is {export_size}B, must be larger than {BUFFER_SIZE}B" + ); + anyhow::ensure!( + !nbd.is_read_only()?, + "error: this NBD export is read-only" + ); + anyhow::ensure!( + nbd.can_multi_conn()?, + "error: this NBD export does not support multi-conn" + ); + drop(nbd); // Close the connection. + + // Start the worker tasks, one per connection. + let mut tasks = JoinSet::new(); + for i in 0..NR_MULTI_CONN { + tasks.spawn(run_thread(i, socket.clone().into(), export_size)); + } + + // Wait for the tasks to complete. + let mut stats = Stats::default(); + while !tasks.is_empty() { + let this_stats = tasks.join_next().await.unwrap().unwrap()?; + stats.requests += this_stats.requests; + } + + // Make sure the number of requests that were required matches what + // we expect. + assert_eq!(stats.requests, NR_MULTI_CONN * NR_CYCLES); + + Ok(()) +} + +async fn run_thread( + task_idx: usize, + socket: PathBuf, + export_size: u64, +) -> anyhow::Result<Stats> { + // Start a new connection to the server. + // We shall spawn many commands concurrently on different tasks and those + // futures must be `'static`, hence we wrap the handle in an [Arc]. + let nbd = Arc::new(libnbd::AsyncHandle::new()?); + nbd.connect_unix(socket).await?; + + let mut rng = SmallRng::seed_from_u64(44 as u64); + + // Issue commands. + let mut stats = Stats::default(); + let mut join_set = JoinSet::new(); + //tokio::time::sleep(std::time::Duration::from_secs(1)).await; + while stats.requests < NR_CYCLES || !join_set.is_empty() { + while stats.requests < NR_CYCLES && join_set.len() < MAX_IN_FLIGHT { + // If we want to issue another request, do so. Note that we reuse + // the same buffer for multiple in-flight requests. It doesn't + // matter here because we're just trying to write random stuff, + // but that would be Very Bad in a real application. + // Simulate a mix of large and small requests. + let size = if rng.gen() { BUFFER_SIZE } else { 512 }; + let offset = rng.gen_range(0..export_size - size as u64); + + let mut buf = [0u8; BUFFER_SIZE]; + let nbd = nbd.clone(); + if rng.gen() { + join_set.spawn(async move { + nbd.pread(&mut buf, offset, None).await + }); + } else { + // Fill the buf with random data. + rng.fill(&mut buf); + join_set + .spawn(async move { nbd.pwrite(&buf, offset, None).await }); + } + stats.requests += 1; + } + join_set.join_next().await.unwrap().unwrap()?; + } + + if task_idx == 0 {} + Ok(stats) +} diff --git a/rust/examples/connect-command.rs b/rust/examples/connect-command.rs new file mode 100644 index 0000000..db4adbe --- /dev/null +++ b/rust/examples/connect-command.rs @@ -0,0 +1,39 @@ +//! This example shows how to run an NBD server +//! (nbdkit) as a subprocess of libnbd. + + +fn main() -> libnbd::Result<()> { + // Create the libnbd handle. + let handle = libnbd::Handle::new()?; + + // Run nbdkit as a subprocess. + let args = [ + "nbdkit", + // You must use ‘-s’ (which tells nbdkit to serve + // a single connection on stdin/stdout). + "-s", + // It is recommended to use ‘--exit-with-parent’ + // to ensure nbdkit is always cleaned up even + // if the main program crashes. + "--exit-with-parent", + // Use this to enable nbdkit debugging. + "-v", + // The nbdkit plugin name - this is a RAM disk. + "memory", + "size=1M", + ]; + handle.connect_command(&args)?; + + // Write some random data to the first sector. + let wbuf: Vec<u8> = (0..512).into_iter().map(|i| (i % 13) as u8).collect(); + handle.pwrite(&wbuf, 0, None)?; + + // Read the first sector back. + let mut rbuf = [0; 512]; + handle.pread(&mut rbuf, 0, None)?; + + // What was read must be exactly the same as what was written. + assert_eq!(wbuf.as_slice(), rbuf.as_slice()); + + Ok(()) +} diff --git a/rust/examples/fetch-first-sector.rs b/rust/examples/fetch-first-sector.rs new file mode 100644 index 0000000..9efb47a --- /dev/null +++ b/rust/examples/fetch-first-sector.rs @@ -0,0 +1,38 @@ +//! This example shows how to connect to an NBD server +//! and fetch and print the first sector (usually the +//! boot sector or partition table or filesystem +//! superblock). +//! +//! You can test it with nbdkit like this: +//! +//! nbdkit -U - floppy . \ +//! --run 'cargo run --example fetch-first-sector -- $unixsocket' +//! +//! The nbdkit floppy plugin creates an MBR disk so the +//! first sector is the partition table. + +use pretty_hex::pretty_hex; +use std::env; + +fn main() -> anyhow::Result<()> { + let nbd = libnbd::Handle::new()?; + + let args = env::args_os().collect::<Vec<_>>(); + if args.len() != 2 { + anyhow::bail!("Usage: {:?} socket", args[0]); + } + let socket = &args[1]; + + // Connect to the NBD server over a + // Unix domain socket. + nbd.connect_unix(socket)?; + + // Read the first sector synchronously. + let mut buf = [0; 512]; + nbd.pread(&mut buf, 0, None)?; + + // Print the sector in hexdump like format. + print!("{}", pretty_hex(&buf)); + + Ok(()) +} diff --git a/rust/examples/get-size.rs b/rust/examples/get-size.rs new file mode 100644 index 0000000..7f31df5 --- /dev/null +++ b/rust/examples/get-size.rs @@ -0,0 +1,29 @@ +//! This example shows how to connect to an NBD +//! server and read the size of the disk. +//! +//! You can test it with nbdkit like this: +//! +//! nbdkit -U - memory 1M \ +//! --run 'cargo run --example get-size -- $unixsocket' + +use std::env; + +fn main() -> anyhow::Result<()> { + let nbd = libnbd::Handle::new()?; + + let args = env::args_os().collect::<Vec<_>>(); + if args.len() != 2 { + anyhow::bail!("Usage: {:?} socket", args[0]); + } + let socket = &args[1]; + + // Connect to the NBD server over a + // Unix domain socket. + nbd.connect_unix(socket)?; + + // Read the size in bytes and print it. + let size = nbd.get_size()?; + println!("{:?}: size = {size} bytes", socket); + + Ok(()) +} diff --git a/rust/run-tests.sh b/rust/run-tests.sh index da7852a..bdc0f16 100755 --- a/rust/run-tests.sh +++ b/rust/run-tests.sh @@ -25,6 +25,13 @@ requires nbdkit --version if [ -z "$VG" ]; then $CARGO test -- --nocapture + $CARGO run --example connect-command + nbdkit -U - memory 1M \ + --run "$CARGO"' run --example get-size -- $unixsocket' + nbdkit -U - floppy . \ + --run "$CARGO"' run --example fetch-first-sector -- $unixsocket' + nbdkit -U - memory 10M \ + --run "$CARGO"' run --example concurrent-read-write -- $unixsocket' else $CARGO test --config "target.'cfg(all())'.runner = \"$VG\"" -- --nocapture fi -- 2.41.0

On 8/2/2023 6:53 PM, Richard W.M. Jones wrote: Yes, I have done that. Best regards, Tage