v0.20.0: Beta release #9

This release fully incorporates the incoming feature contributions that were made during the preceding (0.19.x) beta period. It is anticipated that the next release will be a release candidate for the 1.0 release. New features will not be added until after the final version 1.0 release has been made.

Thanks to current sponsors: Paweł Zmarzły (pzmarzly), Wesley Moore (wezm), M. Herdiansyah (konimex), Coleman McFarland (dontlaugh), q66, saolof, and private sponsors. Thanks also to one-time sponsors Matthew Simmonz (Simmonz), hlclemson, and fictitiousexistence.

Note that some of the new features below were included in the 0.19.x releases by mistake. They are officially supported as of this release. In some cases, some changes have been made to the features as they were found in 0.19.x; these changes are also documented below.

Important changes:

• The 'dinitcheck' utility has been renamed to 'dinit-check'.
• "Soft" reboot ('reboot -s') now invokes shutdown as with other reboot/shutdown types. This means that any shutdown hook will be executed, and filesystems may be unmounted.
• The Meson-based build has been removed.
• The default installation location for binaries, other than "shutdown" and its aliases, is now "/usr/bin". For shutdown etc it is now "/usr/sbin". Previously, the default for all binaries was "/sbin". The BINDIR build variable has been added to specify the location of binaries other than "shutdown" (the SBINDIR variable remains and controls the location of "shutdown"). For those using configure" to generate build configuration, "--bindir=..." can be used to specify the BINDIR directory.

New features:

• Add support for service arguments, allowing any number of services to be created from a single "template" service description file (initial functionality implemented by q66).
• A new @meta command is available in service descriptions to specify meta-information, i.e. information about a service which does not affect how the service runs. This may be useful for use with external tooling. A @meta enable-via subcommand can be used to specify which other service the described service should be added as a dependency of when enabled via "dinitctl enable" (assuming "--from" is not specified); if not specified, the default remains "boot".
• A new "pre-load" variable expansion is used for certain service settings. This takes place before the service-specific environment (if any) has been loaded, but allows substituting global environment variable values and service arguments. (Implemented for different settings by various contributors, including q66 and Mark Karlinsky).
• Support for specifying the "nice" level of service processes. This affects scheduling priority. Implemented by q66.
• Support for setting the ioprio (I/O priority) value on Linux (q66).
• Support for setting the oom-score-adj (OOM killer "score") value on Linux (q66).
• Support for Linux capabilities. This allows services to be granted extra capabilities compared to unprivileged processes, even when they do not run as root. Implemented by q66.
• Support for non-interactive recovery, which after a boot failure runs the recovery service without any interactive prompt ("--auto-recovery") (Jami Kettunen).
• The shutdown type (halt, reboot etc) is now passed as an argument to the shutdown hook script (Mara).
• Support for reboot via kexec on Linux (executing a new kernel without going through firmware initialisation) (el-remph), via "shutdown -k". A kernel must be loaded first (via the "kexec" command, which is part of a separate package).
• Sending the SIGUSR1 signal to dinit now causes it to open the control socket if it has not yet been opened, or if it has been opened previously but is no longer visible in the filesystem. This may be useful for system recovery scenarios.

Changes:

• Pre-load variable expansion is performed on service description file include paths, service dependency settings ('depends-on' etc), the 'env-file' setting path, and various other settings, including directory-based dependency groups ('depends-on.d' etc) (the latter implemented by Mark Karlinksky).
• File paths specified in a service description file or fragment (that is @include'd from another file) are now in general resolved against the location of that service description file or fragment. This means paths can be relative to the location of the service configuration.
• The "secure-bits" setting (which was classified as an in-development feature in previous releases) has been renamed to "securebits", to match relevant Linux documentation (see capabilities(7)).
• Building support for ioprio now requires the <linux/ioprio.h> header to be present on the system (note that ioprio support was considered in-development prior to this release).
• The "configure" script allows specifying build variables containing spaces and shell metacharacters by quoting them using shell quoting rules. Note that such a value supplied on the configure command line must typically be doubly-quoted: once for the invoking shell, and then for processing by configure.
• Default build options for FreeBSD have changed, to avoid a bug in exception handling in clang/libcxxruntime.

Fixes:

• Fix error message from "dinitctl enable" when the "from" service description file cannot be read, to include the correct location of the problematic file.

As usual, a number of minor fixes and improvements (in addition to those already mentioned) were contributed by Mobin Aydinfar.