.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.48.1.
.TH DEBREBUILD "1" "August 2021" "debrebuild 2.21.3+deb11u1" "User Commands"
.SH NAME
debrebuild \- use a buildinfo file and snapshot.d.o to recreate binary packages
.SH SYNOPSIS
.B debrebuild
[\fI\,options\/\fR] \fI\,<buildinfo>\/\fR
.SH DESCRIPTION
.IP
debrebuild <\-\-help|\-h>
.PP
Given a buildinfo file from a Debian package, generate instructions for
attempting to reproduce the binary packages built from the associated source
and build information.
.SH OPTIONS
.TP
\fB\-\-help\fR, \fB\-h\fR
Show this help and exit
.TP
\fB\-\-[no\-]use\-tor\-proxy\fR
Whether to fetch resources via tor (socks://127.0.0.1:9050)
Assumes "apt\-transport\-tor" is installed both in host + chroot
.TP
\fB\-\-[no\-]respect\-build\-path\fR
Whether to setup the build to use the Build\-Path from the
provided .buildinfo file.
.TP
\fB\-\-buildresults\fR
Directory for the build artifacts (default: ./)
.TP
\fB\-\-builder\fR=\fI\,BUILDER\/\fR
Which building software should be used. Possible values are
none, sbuild, mmdebstrap, dpkg and sbuild+unshare. The default
is none. See section BUILDER for details.
.TP
\fB\-\-timestamp\fR, \fB\-t\fR
The required unstable main timestamps from snapshot.d.o if you
already know them, separated by commas, or one of the values
"first_seen" or "metasnap". See section TIMESTAMPS.
.PP
Note: debrebuild can parse buildinfo files with and without a GPG signature.  However,
the signature (if present) is discarded as debrebuild does not support verifying
it.  If the authenticity or integrity of the buildinfo files are important to
you, checking these need to be done before invoking debrebuild, for example by using
dscverify.
.PP
EXAMPLES
.IP
\f(CW$ debrebuild --buildresults=./artifacts --builder=mmdebstrap hello_2.10-2_amd64.buildinfo\fR
.PP
BUILDERS
.PP
debrebuild can use different backends to perform the actual package rebuild.
The desired backend is chosen using the \fB\-\-builder\fR option. The default is
"none".
.TP
none
Dry\-run mode. No build is performed.
.TP
sbuild
Use sbuild to build the package. This requires sbuild to be
setup with schroot chroots of Debian stable distributions.
.TP
mmdebstrap
Use mmdebstrap to build the package. This requires no
setup and no superuser privileges.
.TP
dpkg
Directly run apt\-get and dpkg\-buildpackage on the current
system without chroot. This requires root privileges.
.TP
sbuild+unshare
Use sbuild with the unshare backend. This will create the
chroot and perform the build without superuser privileges
and without any setup.
.PP
TIMESTAMPS
.PP
The \fB\-\-timestamp\fR option allows one to skip the step of figuring out the correct
set of required timestamps by listing them separated by commas in the same
format used in the snapshot.d.o URL. The default is to use the "first_seen"
attribute from the snapshot.d.o API and download multiple Packages files until
all required timestamps are found. To explicitly select this mode, use
\fB\-\-timestamp\fR=\fI\,first_seen\/\fR. Lastly, the metasnap.d.n service can be used to figure
out the right set of timestamps. This mode can be selected by using
\fB\-\-timestamp\fR=\fI\,metasnap\/\fR. In contrast to the "first_seen" mode, the metasnap.d.n
service will always return a minimal set of timestamps if the package versions
were at some point part of Debian unstable main.
.PP
UNSHARE
.PP
Before kernel 5.10.1 or before Debian 11 (Bullseye), unprivileged user
namespaces were disabled in Debian for security reasons. Refer to Debian bug
#898446 for details. To enable user namespaces, run:
.IP
\f(CW$ sudo sysctl -w kernel.unprivileged_userns_clone=1\fR
.PP
The sbuild+unshare builder requires and the mmdebstrap builder benefits from
having unprivileged user namespaces activated. On Ubuntu they are enabled by
default.
.PP
LIMITATIONS
.PP
Currently, the code assumes that all packages were at some point part of Debian
unstable main. This fails for packages from Debian ports, packages from
experimental as well as for locally built packages or packages from third
party repositories. Enabling support for Debian ports and experimental is
conceptually possible and only needs somebody implementing it.