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[git/git.git] / Documentation / git-submodule.txt
1 git-submodule(1)
2 ================
3
4 NAME
5 ----
6 git-submodule - Initialize, update or inspect submodules
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git submodule' [--quiet] add [-b <branch>] [-f|--force] [--name <name>]
13 [--reference <repository>] [--depth <depth>] [--] <repository> [<path>]
14 'git submodule' [--quiet] status [--cached] [--recursive] [--] [<path>...]
15 'git submodule' [--quiet] init [--] [<path>...]
16 'git submodule' [--quiet] deinit [-f|--force] (--all|[--] <path>...)
17 'git submodule' [--quiet] update [--init] [--remote] [-N|--no-fetch]
18 [--[no-]recommend-shallow] [-f|--force] [--rebase|--merge]
19 [--reference <repository>] [--depth <depth>] [--recursive]
20 [--jobs <n>] [--] [<path>...]
21 'git submodule' [--quiet] summary [--cached|--files] [(-n|--summary-limit) <n>]
22 [commit] [--] [<path>...]
23 'git submodule' [--quiet] foreach [--recursive] <command>
24 'git submodule' [--quiet] sync [--recursive] [--] [<path>...]
25
26
27 DESCRIPTION
28 -----------
29 Inspects, updates and manages submodules.
30
31 A submodule allows you to keep another Git repository in a subdirectory
32 of your repository. The other repository has its own history, which does not
33 interfere with the history of the current repository. This can be used to
34 have external dependencies such as third party libraries for example.
35
36 When cloning or pulling a repository containing submodules however,
37 these will not be checked out by default; the 'init' and 'update'
38 subcommands will maintain submodules checked out and at
39 appropriate revision in your working tree.
40
41 Submodules are composed from a so-called `gitlink` tree entry
42 in the main repository that refers to a particular commit object
43 within the inner repository that is completely separate.
44 A record in the `.gitmodules` (see linkgit:gitmodules[5]) file at the
45 root of the source tree assigns a logical name to the submodule and
46 describes the default URL the submodule shall be cloned from.
47 The logical name can be used for overriding this URL within your
48 local repository configuration (see 'submodule init').
49
50 Submodules are not to be confused with remotes, which are other
51 repositories of the same project; submodules are meant for
52 different projects you would like to make part of your source tree,
53 while the history of the two projects still stays completely
54 independent and you cannot modify the contents of the submodule
55 from within the main project.
56 If you want to merge the project histories and want to treat the
57 aggregated whole as a single project from then on, you may want to
58 add a remote for the other project and use the 'subtree' merge strategy,
59 instead of treating the other project as a submodule. Directories
60 that come from both projects can be cloned and checked out as a whole
61 if you choose to go that route.
62
63 COMMANDS
64 --------
65 add::
66 Add the given repository as a submodule at the given path
67 to the changeset to be committed next to the current
68 project: the current project is termed the "superproject".
69 +
70 This requires at least one argument: <repository>. The optional
71 argument <path> is the relative location for the cloned submodule
72 to exist in the superproject. If <path> is not given, the
73 "humanish" part of the source repository is used ("repo" for
74 "/path/to/repo.git" and "foo" for "host.xz:foo/.git").
75 The <path> is also used as the submodule's logical name in its
76 configuration entries unless `--name` is used to specify a logical name.
77 +
78 <repository> is the URL of the new submodule's origin repository.
79 This may be either an absolute URL, or (if it begins with ./
80 or ../), the location relative to the superproject's origin
81 repository (Please note that to specify a repository 'foo.git'
82 which is located right next to a superproject 'bar.git', you'll
83 have to use '../foo.git' instead of './foo.git' - as one might expect
84 when following the rules for relative URLs - because the evaluation
85 of relative URLs in Git is identical to that of relative directories).
86 If the superproject doesn't have an origin configured
87 the superproject is its own authoritative upstream and the current
88 working directory is used instead.
89 +
90 <path> is the relative location for the cloned submodule to
91 exist in the superproject. If <path> does not exist, then the
92 submodule is created by cloning from the named URL. If <path> does
93 exist and is already a valid Git repository, then this is added
94 to the changeset without cloning. This second form is provided
95 to ease creating a new submodule from scratch, and presumes
96 the user will later push the submodule to the given URL.
97 +
98 In either case, the given URL is recorded into .gitmodules for
99 use by subsequent users cloning the superproject. If the URL is
100 given relative to the superproject's repository, the presumption
101 is the superproject and submodule repositories will be kept
102 together in the same relative location, and only the
103 superproject's URL needs to be provided: git-submodule will correctly
104 locate the submodule using the relative URL in .gitmodules.
105
106 status::
107 Show the status of the submodules. This will print the SHA-1 of the
108 currently checked out commit for each submodule, along with the
109 submodule path and the output of 'git describe' for the
110 SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not
111 initialized, `+` if the currently checked out submodule commit
112 does not match the SHA-1 found in the index of the containing
113 repository and `U` if the submodule has merge conflicts.
114 +
115 If `--recursive` is specified, this command will recurse into nested
116 submodules, and show their status as well.
117 +
118 If you are only interested in changes of the currently initialized
119 submodules with respect to the commit recorded in the index or the HEAD,
120 linkgit:git-status[1] and linkgit:git-diff[1] will provide that information
121 too (and can also report changes to a submodule's work tree).
122
123 init::
124 Initialize the submodules recorded in the index (which were
125 added and committed elsewhere) by copying submodule
126 names and urls from .gitmodules to .git/config.
127 Optional <path> arguments limit which submodules will be initialized.
128 It will also copy the value of `submodule.$name.update` into
129 .git/config.
130 The key used in .git/config is `submodule.$name.url`.
131 This command does not alter existing information in .git/config.
132 You can then customize the submodule clone URLs in .git/config
133 for your local setup and proceed to `git submodule update`;
134 you can also just use `git submodule update --init` without
135 the explicit 'init' step if you do not intend to customize
136 any submodule locations.
137
138 deinit::
139 Unregister the given submodules, i.e. remove the whole
140 `submodule.$name` section from .git/config together with their work
141 tree. Further calls to `git submodule update`, `git submodule foreach`
142 and `git submodule sync` will skip any unregistered submodules until
143 they are initialized again, so use this command if you don't want to
144 have a local checkout of the submodule in your working tree anymore. If
145 you really want to remove a submodule from the repository and commit
146 that use linkgit:git-rm[1] instead.
147 +
148 When the command is run without pathspec, it errors out,
149 instead of deinit-ing everything, to prevent mistakes.
150 +
151 If `--force` is specified, the submodule's working tree will
152 be removed even if it contains local modifications.
153
154 update::
155 +
156 --
157 Update the registered submodules to match what the superproject
158 expects by cloning missing submodules and updating the working tree of
159 the submodules. The "updating" can be done in several ways depending
160 on command line options and the value of `submodule.<name>.update`
161 configuration variable. Supported update procedures are:
162
163 checkout;; the commit recorded in the superproject will be
164 checked out in the submodule on a detached HEAD. This is
165 done when `--checkout` option is given, or no option is
166 given, and `submodule.<name>.update` is unset, or if it is
167 set to 'checkout'.
168 +
169 If `--force` is specified, the submodule will be checked out (using
170 `git checkout --force` if appropriate), even if the commit specified
171 in the index of the containing repository already matches the commit
172 checked out in the submodule.
173
174 rebase;; the current branch of the submodule will be rebased
175 onto the commit recorded in the superproject. This is done
176 when `--rebase` option is given, or no option is given, and
177 `submodule.<name>.update` is set to 'rebase'.
178
179 merge;; the commit recorded in the superproject will be merged
180 into the current branch in the submodule. This is done
181 when `--merge` option is given, or no option is given, and
182 `submodule.<name>.update` is set to 'merge'.
183
184 custom command;; arbitrary shell command that takes a single
185 argument (the sha1 of the commit recorded in the
186 superproject) is executed. This is done when no option is
187 given, and `submodule.<name>.update` has the form of
188 '!command'.
189
190 When no option is given and `submodule.<name>.update` is set to 'none',
191 the submodule is not updated.
192
193 If the submodule is not yet initialized, and you just want to use the
194 setting as stored in .gitmodules, you can automatically initialize the
195 submodule with the `--init` option.
196
197 If `--recursive` is specified, this command will recurse into the
198 registered submodules, and update any nested submodules within.
199 --
200 summary::
201 Show commit summary between the given commit (defaults to HEAD) and
202 working tree/index. For a submodule in question, a series of commits
203 in the submodule between the given super project commit and the
204 index or working tree (switched by `--cached`) are shown. If the option
205 `--files` is given, show the series of commits in the submodule between
206 the index of the super project and the working tree of the submodule
207 (this option doesn't allow to use the `--cached` option or to provide an
208 explicit commit).
209 +
210 Using the `--submodule=log` option with linkgit:git-diff[1] will provide that
211 information too.
212
213 foreach::
214 Evaluates an arbitrary shell command in each checked out submodule.
215 The command has access to the variables $name, $path, $sha1 and
216 $toplevel:
217 $name is the name of the relevant submodule section in .gitmodules,
218 $path is the name of the submodule directory relative to the
219 superproject, $sha1 is the commit as recorded in the superproject,
220 and $toplevel is the absolute path to the top-level of the superproject.
221 Any submodules defined in the superproject but not checked out are
222 ignored by this command. Unless given `--quiet`, foreach prints the name
223 of each submodule before evaluating the command.
224 If `--recursive` is given, submodules are traversed recursively (i.e.
225 the given shell command is evaluated in nested submodules as well).
226 A non-zero return from the command in any submodule causes
227 the processing to terminate. This can be overridden by adding '|| :'
228 to the end of the command.
229 +
230 As an example, +git submodule foreach \'echo $path {backtick}git
231 rev-parse HEAD{backtick}'+ will show the path and currently checked out
232 commit for each submodule.
233
234 sync::
235 Synchronizes submodules' remote URL configuration setting
236 to the value specified in .gitmodules. It will only affect those
237 submodules which already have a URL entry in .git/config (that is the
238 case when they are initialized or freshly added). This is useful when
239 submodule URLs change upstream and you need to update your local
240 repositories accordingly.
241 +
242 "git submodule sync" synchronizes all submodules while
243 "git submodule sync \-- A" synchronizes submodule "A" only.
244 +
245 If `--recursive` is specified, this command will recurse into the
246 registered submodules, and sync any nested submodules within.
247
248 OPTIONS
249 -------
250 -q::
251 --quiet::
252 Only print error messages.
253
254 --all::
255 This option is only valid for the deinit command. Unregister all
256 submodules in the working tree.
257
258 -b::
259 --branch::
260 Branch of repository to add as submodule.
261 The name of the branch is recorded as `submodule.<name>.branch` in
262 `.gitmodules` for `update --remote`. A special value of `.` is used to
263 indicate that the name of the branch in the submodule should be the
264 same name as the current branch in the current repository.
265
266 -f::
267 --force::
268 This option is only valid for add, deinit and update commands.
269 When running add, allow adding an otherwise ignored submodule path.
270 When running deinit the submodule working trees will be removed even
271 if they contain local changes.
272 When running update (only effective with the checkout procedure),
273 throw away local changes in submodules when switching to a
274 different commit; and always run a checkout operation in the
275 submodule, even if the commit listed in the index of the
276 containing repository matches the commit checked out in the
277 submodule.
278
279 --cached::
280 This option is only valid for status and summary commands. These
281 commands typically use the commit found in the submodule HEAD, but
282 with this option, the commit stored in the index is used instead.
283
284 --files::
285 This option is only valid for the summary command. This command
286 compares the commit in the index with that in the submodule HEAD
287 when this option is used.
288
289 -n::
290 --summary-limit::
291 This option is only valid for the summary command.
292 Limit the summary size (number of commits shown in total).
293 Giving 0 will disable the summary; a negative number means unlimited
294 (the default). This limit only applies to modified submodules. The
295 size is always limited to 1 for added/deleted/typechanged submodules.
296
297 --remote::
298 This option is only valid for the update command. Instead of using
299 the superproject's recorded SHA-1 to update the submodule, use the
300 status of the submodule's remote-tracking branch. The remote used
301 is branch's remote (`branch.<name>.remote`), defaulting to `origin`.
302 The remote branch used defaults to `master`, but the branch name may
303 be overridden by setting the `submodule.<name>.branch` option in
304 either `.gitmodules` or `.git/config` (with `.git/config` taking
305 precedence).
306 +
307 This works for any of the supported update procedures (`--checkout`,
308 `--rebase`, etc.). The only change is the source of the target SHA-1.
309 For example, `submodule update --remote --merge` will merge upstream
310 submodule changes into the submodules, while `submodule update
311 --merge` will merge superproject gitlink changes into the submodules.
312 +
313 In order to ensure a current tracking branch state, `update --remote`
314 fetches the submodule's remote repository before calculating the
315 SHA-1. If you don't want to fetch, you should use `submodule update
316 --remote --no-fetch`.
317 +
318 Use this option to integrate changes from the upstream subproject with
319 your submodule's current HEAD. Alternatively, you can run `git pull`
320 from the submodule, which is equivalent except for the remote branch
321 name: `update --remote` uses the default upstream repository and
322 `submodule.<name>.branch`, while `git pull` uses the submodule's
323 `branch.<name>.merge`. Prefer `submodule.<name>.branch` if you want
324 to distribute the default upstream branch with the superproject and
325 `branch.<name>.merge` if you want a more native feel while working in
326 the submodule itself.
327
328 -N::
329 --no-fetch::
330 This option is only valid for the update command.
331 Don't fetch new objects from the remote site.
332
333 --checkout::
334 This option is only valid for the update command.
335 Checkout the commit recorded in the superproject on a detached HEAD
336 in the submodule. This is the default behavior, the main use of
337 this option is to override `submodule.$name.update` when set to
338 a value other than `checkout`.
339 If the key `submodule.$name.update` is either not explicitly set or
340 set to `checkout`, this option is implicit.
341
342 --merge::
343 This option is only valid for the update command.
344 Merge the commit recorded in the superproject into the current branch
345 of the submodule. If this option is given, the submodule's HEAD will
346 not be detached. If a merge failure prevents this process, you will
347 have to resolve the resulting conflicts within the submodule with the
348 usual conflict resolution tools.
349 If the key `submodule.$name.update` is set to `merge`, this option is
350 implicit.
351
352 --rebase::
353 This option is only valid for the update command.
354 Rebase the current branch onto the commit recorded in the
355 superproject. If this option is given, the submodule's HEAD will not
356 be detached. If a merge failure prevents this process, you will have
357 to resolve these failures with linkgit:git-rebase[1].
358 If the key `submodule.$name.update` is set to `rebase`, this option is
359 implicit.
360
361 --init::
362 This option is only valid for the update command.
363 Initialize all submodules for which "git submodule init" has not been
364 called so far before updating.
365
366 --name::
367 This option is only valid for the add command. It sets the submodule's
368 name to the given string instead of defaulting to its path. The name
369 must be valid as a directory name and may not end with a '/'.
370
371 --reference <repository>::
372 This option is only valid for add and update commands. These
373 commands sometimes need to clone a remote repository. In this case,
374 this option will be passed to the linkgit:git-clone[1] command.
375 +
376 *NOTE*: Do *not* use this option unless you have read the note
377 for linkgit:git-clone[1]'s `--reference` and `--shared` options carefully.
378
379 --recursive::
380 This option is only valid for foreach, update, status and sync commands.
381 Traverse submodules recursively. The operation is performed not
382 only in the submodules of the current repo, but also
383 in any nested submodules inside those submodules (and so on).
384
385 --depth::
386 This option is valid for add and update commands. Create a 'shallow'
387 clone with a history truncated to the specified number of revisions.
388 See linkgit:git-clone[1]
389
390 --[no-]recommend-shallow::
391 This option is only valid for the update command.
392 The initial clone of a submodule will use the recommended
393 `submodule.<name>.shallow` as provided by the .gitmodules file
394 by default. To ignore the suggestions use `--no-recommend-shallow`.
395
396 -j <n>::
397 --jobs <n>::
398 This option is only valid for the update command.
399 Clone new submodules in parallel with as many jobs.
400 Defaults to the `submodule.fetchJobs` option.
401
402 <path>...::
403 Paths to submodule(s). When specified this will restrict the command
404 to only operate on the submodules found at the specified paths.
405 (This argument is required with add).
406
407 FILES
408 -----
409 When initializing submodules, a .gitmodules file in the top-level directory
410 of the containing repository is used to find the url of each submodule.
411 This file should be formatted in the same way as `$GIT_DIR/config`. The key
412 to each submodule url is "submodule.$name.url". See linkgit:gitmodules[5]
413 for details.
414
415 GIT
416 ---
417 Part of the linkgit:git[1] suite