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'\"! tbl | nroff \-man
'\" t macro stdmacro

.de SAMPLE
.br
.RS 0
.nf
.nh
..
.de ESAMPLE
.hy
.fi
.RE
..

.TH DEBUGINFOD-FIND 1
.SH NAME
debuginfod-find \- request debuginfo-related data

.SH SYNOPSIS
.B debuginfod-find [\fIOPTION\fP]... debuginfo \fIBUILDID\fP
.br
.B debuginfod-find [\fIOPTION\fP]... debuginfo \fIPATH\fP
.br
.B debuginfod-find [\fIOPTION\fP]... executable \fIBUILDID\fP
.br
.B debuginfod-find [\fIOPTION\fP]... executable \fIPATH\fP
.br
.B debuginfod-find [\fIOPTION\fP]... source \fIBUILDID\fP \fI/FILENAME\fP
.br
.B debuginfod-find [\fIOPTION\fP]... source \fIPATH\fP \fI/FILENAME\fP
.br
.B debuginfod-find [\fIOPTION\fP]... metadata \fIKEY\fP \fIVALUE\fP

.SH DESCRIPTION
\fBdebuginfod-find\fP queries one or more \fBdebuginfod\fP servers for
debuginfo-related data.  In case of a match, it saves the the
requested file into a local cache, prints the file name to standard
output, and exits with a success status of 0.  In case of any error,
it exits with a failure status and an error message to standard error.

.\" Much of the following text is duplicated with debuginfod.8

The debuginfod system uses buildids to identify debuginfo-related data.
These are stored as binary notes in ELF/DWARF files, and are
represented as lowercase hexadecimal.  For example, for a program
/bin/ls, look at the ELF note GNU_BUILD_ID:

.SAMPLE
% readelf -n /bin/ls | grep -A4 build.id
Note section [ 4] '.note.gnu.buildid' of 36 bytes at offset 0x340:
Owner          Data size  Type
GNU                   20  GNU_BUILD_ID
Build ID: 8713b9c3fb8a720137a4a08b325905c7aaf8429d
.ESAMPLE

Then the hexadecimal BUILDID is simply:

.SAMPLE
8713b9c3fb8a720137a4a08b325905c7aaf8429d
.ESAMPLE

In place of the hexadecimal \fIBUILDID\fP, debuginfod-find also
accepts a path name to to an ELF binary, from which it extracts the
buildid.  In this case, ensure the file name has some character other
than \fB[0-9a-f]\fP.  Files ambiguously named files like
"\fBdeadbeef\fP" can be passed with a \fB./deadbeef\fP extra path
component.


.SS debuginfo \fIBUILDID\fP

If the given buildid is known to a server, this request will result
in a binary object that contains the customary \fB.*debug_*\fP
sections.  This may be a split debuginfo file as created by
\fBstrip\fP, or it may be an original unstripped executable.

.SS executable \fIBUILDID\fP

If the given buildid is known to the server, this request will result
in a binary object that contains the normal executable segments.  This
may be a executable stripped by \fBstrip\fP, or it may be an original
unstripped executable.  \fBET_DYN\fP shared libraries are considered
to be a type of executable.

.SS source \fIBUILDID\fP \fI/SOURCE/FILE\fP

If the given buildid is known to the server, this request will result
in a binary object that contains the source file mentioned.  The path
should be absolute.  Relative path names commonly appear in the DWARF
file's source directory, but these paths are relative to
individual compilation unit AT_comp_dir paths, and yet an executable
is made up of multiple CUs.  Therefore, to disambiguate, debuginfod
expects source queries to prefix relative path names with the CU
compilation-directory, followed by a mandatory "/".

Note: for software packaged by distributions, the CU
compilation-directory may not be obvious.  It can be found by
inspecting AT_comp_dir values in downloaded debuginfo.  For example,
the comp_dir of the Fedora 37 version of /bin/ls can be found as
follows:

.SAMPLE
% debuginfod-find debuginfo /bin/ls
~/.cache/debuginfod_client/03529d48345409576cd5c82a56ad08555088d353/
% eu-readelf -w ~/.cache/debuginfod_client/03529d48345409576cd5c82a56ad08555088d353/debuginfo | grep comp_dir
           comp_dir             (line_strp) "/usr/src/debug/coreutils-9.1-6.fc37.x86_64/separate"
.ESAMPLE

Note: the caller may or may not elide \fB../\fP or \fB/./\fP or extraneous
\fB///\fP sorts of path components in the directory names.  debuginfod
accepts both forms.  Specifically, debuginfod canonicalizes path names
according to RFC3986 section 5.2.4 (Remove Dot Segments), plus reducing
any \fB//\fP to \fB/\fP in the path.

For example:
.TS
l l.
#include <stdio.h>	source BUILDID /usr/include/stdio.h
/path/to/foo.c	source BUILDID /path/to/foo.c
\../bar/foo.c AT_comp_dir=/zoo/	source BUILDID /zoo//../bar/foo.c
.TE

.SS metadata \fIKEY\fP \fIVALUE\fP

All designated debuginfod servers are queried for metadata about files
in their index.  Different search keys may be supported by different
servers.

.TS
l l l .
KEY	VALUE	DESCRIPTION

\fBfile\fP	path	exact match \fIpath\fP, including in archives
\fBglob\fP	pattern	glob match \fIpattern\fP, including in archives
.TE

The results of the search are output to \fBstdout\fP as a JSON array
of objects, supplying metadata about each match.  This metadata report
may be cached.  It may be incomplete and may contain duplicates.  For
each match, the result is a JSON object with these fields.  Additional
fields may be present.

.TS
l l l .
NAME	TYPE	DESCRIPTION

\fBbuildid\fP	string	hexadecimal buildid associated with the file
\fBtype\fP	string	one of \fBdebuginfo\fP or \fBexecutable\fP
\fBfile\fP	string	matched file name, outside or inside the archive
\fBarchive\fP	string	archive containing matched file name, if any
.TE

.SH "OPTIONS"

.TP
.B "\-v"
Increase verbosity, including printing frequent download-progress messages
and printing the http response headers from the server.


.SH "SECURITY"

debuginfod-find \fBdoes not\fP include any particular security
features.  It trusts that the binaries returned by the debuginfod(s)
are accurate.  Therefore, the list of servers should include only
trustworthy ones.  If accessed across HTTP rather than HTTPS, the
network should be trustworthy.  Authentication information through
the internal \fIlibcurl\fP library is not currently enabled, except
for the basic plaintext \%\fIhttp[s]://userid:password@hostname/\fP style.
(The debuginfod server does not perform authentication, but a front-end
proxy server could.)

.nr zZ 1
.so man7/debuginfod-client-config.7

.SH "SEE ALSO"
.I "debuginfod(8)"
.I "debuginfod_find_debuginfod(3)"