I'm pleased to announce the release of nbdkit 1.20, a high performance plugin-based Network Block Device (NBD) server. https://en.wikipedia.org/wiki/Network_block_device Key features of nbdkit: * Multithreaded NBD server written in C with good performance. * Minimal dependencies for the basic server. * Liberal license (BSD) allows nbdkit to be linked to proprietary libraries or included in proprietary code. * Well-documented, simple plugin API with a stable ABI guarantee. Lets you export “unconventional” block devices easily. * You can write plugins in C, [new!] Go, Lua, Perl, Python, OCaml, Ruby, Rust, shell script or Tcl. * Filters can be stacked in front of plugins to transform the output. Git: https://github.com/libguestfs/nbdkit Download: http://download.libguestfs.org/nbdkit/1.20-stable/ Fedora: https://koji.fedoraproject.org/koji/packageinfo?packageID=16469 Release notes (http://libguestfs.org/nbdkit-release-notes-1.20.1.html) These are the release notes for nbdkit stable release 1.20. This describes the major changes since 1.18. nbdkit 1.20.0 was released on 2nd May 2020. Security There were no security issues found. All past security issues and information about how to report new ones can be found in nbdkit-security(1). Plugins New nbdkit-tmpdisk-plugin(1) is a scriptable “remote tmpfs” for creating temporary filesystems (eg. for thin clients), and also for blank or prepopulated temporary disks. nbdkit-data-plugin(1) now has support for prepopulating disks with more complex test patterns such as repeated sequences of bytes. nbdkit-curl-plugin(1) now supports setting a proxy, enabling TCP keepalives, and disabling Nagle’s algorithm. nbdkit-perl-plugin(1) now supports API version 2. In particular the full NBD client flags are visible to plugins, along with support for the ".get_ready" callback. Also there is a new function "Nbdkit::debug" which is a wrapper around the "nbdkit_debug" API. nbdkit-vddk-plugin(1) drops support for VDDK 5.1.1. This version was last updated in 2014 and is no longer supported by VMware. Since this was the last version of VDDK to support i686, 32-bit support is also dropped (Eric Blake). Language bindings Plugins may now be written in Golang, see nbdkit-golang-plugin(3) (thanks Dan Berrangé, James Shubin). OCaml plugins can now access "nbdkit_realpath", "nbdkit_nanosleep", "nbdkit_export_name" and "nbdkit_shutdown". Python plugins now transparently support fail-fast zero (Eric Blake). Filters New nbdkit-exitlast-filter(1) causes nbdkit to exit after the last client connection. New nbdkit-limit-filter(1) allows you to limit the number of clients which can simultaneously connect to any plugin. Server The --run option now waits for the nbdkit plugin and nbdkit to exit before returning to the caller. This allows for more predictable clean up in shell scripts using this feature. nbdkit --dump-config output now includes separate lines for "version_major" and "version_minor", making it easier to find out from shell scripts which version of nbdkit is installed. nbdkit -s option (which connects to the client over stdin/stdout) now rejects various options that would also try to read from or write to stdin/stdout, for example --dump-plugin or "password=-" (Eric Blake). API New "nbdkit_shutdown" call which allows plugins to ask for nbdkit to exit. This is used to implement the new "exitlast" filter. New "nbdkit_stdio_safe" call allows plugins to check if reading from stdin or writing to stdout is safe, eg. if it is safe to read passwords interactively (Eric Blake). "can_*" callbacks which return booleans can return any value ≥ 1 to mean true. Previous versions of nbdkit had inconsistent behaviour if plugins returned anything other than 1 for true (Eric Blake). Bug fixes nbdkit-tar-plugin(1) now works and there is a regression test for it. nbdkit-curl-plugin(1) "-D curl.version=1" option now works. Fixed a rare hang when closing a connection in nbdkit-nbd-plugin(1) (Eric Blake). Fix compilation on certain platforms with clang (Khem Raj). Don’t leak $tmpdir from nbdkit-sh-plugin(1) into the --run subcommand. nbdkit now correctly sets "FD_CLOEXEC" when using systemd socket activation (Eric Blake). Documentation The nbdkit-plugin(3) man page has been overhauled completely to make it easier to follow. Also we now have documentation for how to compile plugins in various environments which was missing before. Tests All valgrind tests now pass. “Old plugin” tests were added for v1.18.2 on x86-64, and a variety of old plugins compiled on i686. The i686 plugins will allow us to test for regressions in 32 bit support. Tests of the nbd plugin should now be stable (Eric Blake). There is an additional test combining the offset and truncate filters, which tests several corner cases as well as providing tests of error handling between layers. Build nbdkit-nbd-plugin(1) now requires libnbd. (If libnbd is not present at build time then this plugin is not built). The fallback code in this plugin which made NBD connections by constructing NBD command packets without using libnbd has been removed (Eric Blake). scripts/git.orderfile has been improved so that commands like "git diff" and "git show" display OCaml sources in a natural order with interface first followed by implementation. Various fixes for MinGW. Note MinGW / MSYS support is a work in progress and not finished yet (Frank Gu). Multiple fixes to Haiku build. awk(1) is no longer required to run the tests. It was a “hidden” required dependency, but all use of it has now been eliminated. Internals There is now an internal utility library for creating vectors/lists of objects, for example lists of strings (common/utils/vector.h). It is widely used by the server, plugins and filters. README discusses how to use lcov(1) for code coverage reports. SEE ALSO nbdkit(1). AUTHORS Authors of nbdkit 1.20: Eric Blake (33 commits) Khem Raj (1 commit) Richard W.M. Jones (134 commits) Frank Gu (6 commits) -- 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