1DEBUGINFOD-FIND(1) General Commands Manual DEBUGINFOD-FIND(1)
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8 debuginfod-find - request debuginfo-related data
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12 debuginfod-find [OPTION]... debuginfo BUILDID
13 debuginfod-find [OPTION]... debuginfo PATH
14 debuginfod-find [OPTION]... executable BUILDID
15 debuginfod-find [OPTION]... executable PATH
16 debuginfod-find [OPTION]... source BUILDID /FILENAME
17 debuginfod-find [OPTION]... source PATH /FILENAME
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21 debuginfod-find queries one or more debuginfod servers for debuginfo-
22 related data. In case of a match, it saves the the requested file into
23 a local cache, prints the file name to standard output, and exits with
24 a success status of 0. In case of any error, it exits with a failure
25 status and an error message to standard error.
26 The debuginfod system uses buildids to identify debuginfo-related data.
29 These are stored as binary notes in ELF/DWARF files, and are repre‐
30 sented as lowercase hexadecimal. For example, for a program /bin/ls,
31 look at the ELF note GNU_BUILD_ID:
32 % readelf -n /bin/ls | grep -A4 build.id
34 Note section [ 4] '.note.gnu.buildid' of 36 bytes at offset 0x340:
35 Owner Data size Type
36 GNU 20 GNU_BUILD_ID
37 Build ID: 8713b9c3fb8a720137a4a08b325905c7aaf8429d
38 Then the hexadecimal BUILDID is simply:
40 8713b9c3fb8a720137a4a08b325905c7aaf8429d
42 In place of the hexadecimal BUILDID, debuginfod-find also accepts a
44 path name to to an ELF binary, from which it extracts the buildid. In
45 this case, ensure the file name has some character other than [0-9a-f].
46 Files ambiguously named files like "deadbeef" can be passed with a
47 ./deadbeef extra path component.
48 debuginfo BUILDID
52 If the given buildid is known to a server, this request will result in
53 a binary object that contains the customary .*debug_* sections. This
54 may be a split debuginfo file as created by strip, or it may be an
55 original unstripped executable.
56 executable BUILDID
59 If the given buildid is known to the server, this request will result
60 in a binary object that contains the normal executable segments. This
61 may be a executable stripped by strip, or it may be an original un‐
62 stripped executable. ET_DYN shared libraries are considered to be a
63 type of executable.
64 source BUILDID /SOURCE/FILE
67 If the given buildid is known to the server, this request will result
68 in a binary object that contains the source file mentioned. The path
69 should be absolute. Relative path names commonly appear in the DWARF
70 file's source directory, but these paths are relative to individual
71 compilation unit AT_comp_dir paths, and yet an executable is made up of
72 multiple CUs. Therefore, to disambiguate, debuginfod expects source
73 queries to prefix relative path names with the CU compilation-directo‐
74 ry, followed by a mandatory "/".
75 Note: the caller may or may not elide ../ or /./ or extraneous ///
77 sorts of path components in the directory names. debuginfod accepts
78 both forms. Specifically, debuginfod canonicalizes path names accord‐
79 ing to RFC3986 section 5.2.4 (Remove Dot Segments), plus reducing any
80 // to / in the path.
81 For example:
83 #include <stdio.h> source BUILDID /usr/include/stdio.h
85 /path/to/foo.c source BUILDID /path/to/foo.c
86 ../bar/foo.c AT_comp_dir=/zoo/ source BUILDID /zoo//../bar/foo.c
87
90 -v Increase verbosity, including printing frequent download-
91 progress messages and printing the http response headers from
92 the server.
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97 debuginfod-find does not include any particular security features. It
98 trusts that the binaries returned by the debuginfod(s) are accurate.
99 Therefore, the list of servers should include only trustworthy ones.
100 If accessed across HTTP rather than HTTPS, the network should be trust‐
101 worthy. Authentication information through the internal libcurl li‐
102 brary is not currently enabled, except for the basic plaintext
103 http[s]://userid:password@hostname/ style. (The debuginfod server does
104 not perform authentication, but a front-end proxy server could.)
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110 $TMPDIR
111 This environment variable points to a file system to be used for
112 temporary files. The default is /tmp.
113 $DEBUGINFOD_URLS
116 This environment variable contains a list of URL prefixes for
117 trusted debuginfod instances. Alternate URL prefixes are sepa‐
118 rated by space. Avoid referential loops that cause a server to
119 contact itself, directly or indirectly - the results would be
120 hilarious.
121 $DEBUGINFOD_CACHE_PATH
124 This environment variable governs the location of the cache
125 where downloaded files and cache-control files are kept. The
126 default directory is chosen based on other environment vari‐
127 ables, see below.
128 $DEBUGINFOD_PROGRESS
131 This environment variable governs the default progress function.
132 If set, and if a progressfn is not explicitly set, then the li‐
133 brary will configure a default progressfn. This function will
134 append a simple progress message periodically to stderr. The
135 default is no progress function output.
136 $DEBUGINFOD_VERBOSE
139 This environment variable governs the default file descriptor
140 for verbose output. If set, and if a verbose fd is not explic‐
141 itly set, then the verbose output will be produced on
142 STDERR_FILENO.
143 $DEBUGINFOD_RETRY_LIMIT
146 This environment variable governs the default limit of retry at‐
147 tempts. If a query failed with errno other than ENOENT, will
148 initiate several attempts within the limit.
149 $DEBUGINFOD_TIMEOUT
152 This environment variable governs the download commencing time‐
153 out for each debuginfod HTTP connection. A server that fails to
154 provide at least 100K of data within this many seconds is
155 skipped. The default is 90 seconds. (Zero or negative means "no
156 timeout".)
157 $DEBUGINFOD_MAXTIME
160 This environment variable dictates how long the client will wait
161 to complete the download a file found on a server in seconds. It
162 is best used to ensure that a file is downloaded quickly or be
163 rejected. The default is 0 (infinite time).
164 $DEBUGINFOD_MAXSIZE
167 This environment variable dictates the maximum size of a file to
168 download in bytes. This is best used if the user would like to
169 ensure only small files are downloaded. A value of 0 causes no
170 consideration for size, and the client may attempt to download a
171 file of any size. The default is 0 (infinite size).
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175 Before each query, the debuginfod client library checks for a need to
176 clean the cache. If it's time to clean, the library traverses the
177 cache directory and removes downloaded debuginfo-related artifacts and
178 newly empty directories, if they have not been accessed recently.
179 Control files are located directly under the cache directory. They
181 contain simple decimal numbers to set cache-related configuration pa‐
182 rameters. If the files do not exist, the client library creates the
183 files with the default parameter values as content.
184 After each query, the debuginfod client library deposits newly received
186 files into a directory & file that is named based on the build-id. A
187 failed query is also cached by a special file. The naming convention
188 used for these artifacts is deliberately undocumented.
189 $XDG_CACHE_HOME/debuginfod_client/
192 Default cache directory, if $XDG_CACHE_HOME is set.
193 $HOME/.cache/debuginfod_client/
196 Default cache directory, if $XDG_CACHE_HOME is not set.
197 $HOME/.debuginfod_client_cache/
200 Deprecated cache directory, used only if preexisting.
201 cache_clean_interval_s
204 This control file gives the interval between cache cleaning
205 rounds, in seconds. The default is 86400, one day. 0 means
206 "immediately".
207 max_unused_age_s
210 This control file sets how long unaccessed debuginfo-related
211 files are retained, in seconds. The default is 604800, one
212 week. 0 means "immediately".
213 cache_miss_s
216 This control file sets how long to remember a query failure, in
217 seconds. New queries for the same artifacts within this time
218 window are short-circuited (returning an immediate failure in‐
219 stead of sending a new query to servers). This accelerates
220 queries that probably would still fail. The default is 600, 10
221 minutes. 0 means "forget immediately".
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225 debuginfod(8) debuginfod_find_debuginfod(3)
226 DEBUGINFOD-FIND(1)