1 ;;; GNU Guix --- Functional package management for GNU
2 ;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
3 ;;; Copyright © 2018, 2019 Ludovic Courtès <ludo@gnu.org>
5 ;;; This file is part of GNU Guix.
7 ;;; GNU Guix is free software; you can redistribute it and/or modify it
8 ;;; under the terms of the GNU General Public License as published by
9 ;;; the Free Software Foundation; either version 3 of the License, or (at
10 ;;; your option) any later version.
12 ;;; GNU Guix is distributed in the hope that it will be useful, but
13 ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
14 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 ;;; GNU General Public License for more details.
17 ;;; You should have received a copy of the GNU General Public License
18 ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
20 (define-module (guix git)
22 #:use-module (git object)
23 #:use-module (guix i18n)
24 #:use-module (guix base32)
25 #:use-module (gcrypt hash)
26 #:use-module ((guix build utils) #:select (mkdir-p))
27 #:use-module (guix store)
28 #:use-module (guix utils)
29 #:use-module (guix records)
30 #:use-module (guix gexp)
31 #:use-module (guix sets)
32 #:use-module (rnrs bytevectors)
33 #:use-module (ice-9 match)
34 #:use-module (srfi srfi-1)
35 #:use-module (srfi srfi-11)
36 #:use-module (srfi srfi-34)
37 #:use-module (srfi srfi-35)
38 #:export (%repository-cache-directory
39 honor-system-x509-certificates!
42 update-cached-checkout
43 latest-repository-commit
51 ;; XXX: Use this hack instead of #:autoload to avoid compilation errors.
52 ;; See <http://bugs.gnu.org/12202>.
53 (module-autoload! (current-module)
54 '(git submodule) '(repository-submodules))
56 (define %repository-cache-directory
57 (make-parameter (string-append (cache-directory #:ensure? #f)
60 (define (honor-system-x509-certificates!)
61 "Use the system's X.509 certificates for Git checkouts over HTTPS. Honor
62 the 'SSL_CERT_FILE' and 'SSL_CERT_DIR' environment variables."
63 ;; On distros such as CentOS 7, /etc/ssl/certs contains only a couple of
64 ;; files (instead of all the certificates) among which "ca-bundle.crt". On
65 ;; other distros /etc/ssl/certs usually contains the whole set of
66 ;; certificates along with "ca-certificates.crt". Try to choose the right
68 (let ((file (letrec-syntax ((choose
72 (if (and f (file-exists? f))
77 (choose (getenv "SSL_CERT_FILE")
78 "/etc/ssl/certs/ca-certificates.crt"
79 "/etc/ssl/certs/ca-bundle.crt")))
80 (directory (or (getenv "SSL_CERT_DIR") "/etc/ssl/certs")))
82 (and=> (stat directory #f)
84 (> (stat:nlink st) 2))))
86 (set-tls-certificate-locations! directory file)
89 (define %certificates-initialized?
90 ;; Whether 'honor-system-x509-certificates!' has already been called.
93 (define-syntax-rule (with-libgit2 thunk ...)
95 ;; XXX: The right thing to do would be to call (libgit2-shutdown) here,
96 ;; but pointer finalizers used in guile-git may be called after shutdown,
97 ;; resulting in a segfault. Hence, let's skip shutdown call for now.
99 (unless %certificates-initialized?
100 (honor-system-x509-certificates!)
101 (set! %certificates-initialized? #t))
104 (define* (url-cache-directory url
105 #:optional (cache-directory
106 (%repository-cache-directory))
108 "Return the directory associated to URL in %repository-cache-directory."
111 (bytevector->base32-string
112 (sha256 (string->utf8 (if recursive?
113 (string-append "R:" url)
116 (define (clone* url directory)
117 "Clone git repository at URL into DIRECTORY. Upon failure,
118 make sure no empty directory is left behind."
119 (with-throw-handler #t
123 ;; Note: Explicitly pass options to work around the invalid default
124 ;; value in Guile-Git: <https://bugs.gnu.org/29238>.
125 (if (module-defined? (resolve-interface '(git))
127 (clone url directory (clone-init-options))
128 (clone url directory)))
130 (false-if-exception (rmdir directory)))))
132 (define (url+commit->name url sha1)
133 "Return the string \"<REPO-NAME>-<SHA1:7>\" where REPO-NAME is the name of
134 the git repository, extracted from URL and SHA1:7 the seven first digits
137 (string-replace-substring
138 (last (string-split url #\/)) ".git" "")
139 "-" (string-take sha1 7)))
141 (define (switch-to-ref repository ref)
142 "Switch to REPOSITORY's branch, commit or tag specified by REF. Return the
143 OID (roughly the commit hash) corresponding to REF."
145 (let resolve ((ref ref))
148 (let ((oid (reference-target
149 (branch-lookup repository branch BRANCH-REMOTE))))
150 (object-lookup repository oid)))
152 (let ((len (string-length commit)))
153 ;; 'object-lookup-prefix' appeared in Guile-Git in Mar. 2018, so we
154 ;; can't be sure it's available. Furthermore, 'string->oid' used to
155 ;; read out-of-bounds when passed a string shorter than 40 chars,
156 ;; which is why we delay calls to it below.
158 (if (module-defined? (resolve-interface '(git object))
159 'object-lookup-prefix)
160 (object-lookup-prefix repository (string->oid commit) len)
163 (message "long Git object ID is required")))))
164 (object-lookup repository (string->oid commit)))))
165 (('tag-or-commit . str)
166 (if (or (> (string-length str) 40)
167 (not (string-every char-set:hex-digit str)))
168 (resolve `(tag . ,str)) ;definitely a tag
171 (resolve `(tag . ,str)))
173 ;; There's no such tag, so it must be a commit ID.
174 (resolve `(commit . ,str))))))
176 (let ((oid (reference-name->oid repository
177 (string-append "refs/tags/" tag))))
178 ;; Get the commit that the tag at OID refers to. This is not
179 ;; strictly needed, but it's more consistent to always return the
181 (object-lookup repository
182 (tag-target-id (tag-lookup repository oid))))))))
184 (reset repository obj RESET_HARD)
187 (define (call-with-repository directory proc)
188 (let ((repository #f))
191 (set! repository (repository-open directory)))
195 (repository-close! repository)))))
197 (define-syntax-rule (with-repository directory repository exp ...)
198 "Open the repository at DIRECTORY and bind REPOSITORY to it within the
199 dynamic extent of EXP."
200 (call-with-repository directory
201 (lambda (repository) exp ...)))
203 (define* (update-submodules repository
204 #:key (log-port (current-error-port)))
205 "Update the submodules of REPOSITORY, a Git repository object."
206 ;; Guile-Git < 0.2.0 did not have (git submodule).
207 (if (false-if-exception (resolve-interface '(git submodule)))
208 (for-each (lambda (name)
209 (let ((submodule (submodule-lookup repository name)))
210 (format log-port (G_ "updating submodule '~a'...~%")
212 (submodule-update submodule)
214 ;; Recurse in SUBMODULE.
215 (let ((directory (string-append
216 (repository-working-directory repository)
217 "/" (submodule-path submodule))))
218 (with-repository directory repository
219 (update-submodules repository
220 #:log-port log-port)))))
221 (repository-submodules repository))
222 (format (current-error-port)
223 (G_ "Support for submodules is missing; \
224 please upgrade Guile-Git.~%"))))
226 (define (reference-available? repository ref)
227 "Return true if REF, a reference such as '(commit . \"cabba9e\"), is
228 definitely available in REPOSITORY, false otherwise."
233 (->bool (commit-lookup repository (string->oid commit))))
234 (lambda (key error . rest)
235 (if (= GIT_ENOTFOUND (git-error-code error))
237 (apply throw key error rest)))))
241 (define* (update-cached-checkout url
243 (ref '(branch . "master"))
245 (log-port (%make-void-port "w"))
248 url (%repository-cache-directory)
249 #:recursive? recursive?)))
250 "Update the cached checkout of URL to REF in CACHE-DIRECTORY. Return two
251 values: the cache directory name, and the SHA1 commit (a string) corresponding
254 REF is pair whose key is [branch | commit | tag | tag-or-commit ] and value
255 the associated data: [<branch name> | <sha1> | <tag name> | <string>].
257 When RECURSIVE? is true, check out submodules as well, if any."
258 (define canonical-ref
259 ;; We used to require callers to specify "origin/" for each branch, which
260 ;; made little sense since the cache should be transparent to them. So
261 ;; here we append "origin/" if it's missing and otherwise keep it.
264 `(branch . ,(if (string-prefix? "origin/" branch)
266 (string-append "origin/" branch))))
270 (let* ((cache-exists? (openable-repository? cache-directory))
271 (repository (if cache-exists?
272 (repository-open cache-directory)
273 (clone* url cache-directory))))
274 ;; Only fetch remote if it has not been cloned just before.
275 (when (and cache-exists?
276 (not (reference-available? repository ref)))
277 (remote-fetch (remote-lookup repository "origin")))
279 (update-submodules repository #:log-port log-port))
280 (let ((oid (switch-to-ref repository canonical-ref)))
282 ;; Reclaim file descriptors and memory mappings associated with
283 ;; REPOSITORY as soon as possible.
284 (when (module-defined? (resolve-interface '(git repository))
286 (repository-close! repository))
288 (values cache-directory (oid->string oid))))))
290 (define* (latest-repository-commit store url
293 (log-port (%make-void-port "w"))
295 (%repository-cache-directory))
296 (ref '(branch . "master")))
297 "Return two values: the content of the git repository at URL copied into a
298 store directory and the sha1 of the top level commit in this directory. The
299 reference to be checkout, once the repository is fetched, is specified by REF.
300 REF is pair whose key is [branch | commit | tag] and value the associated
301 data, respectively [<branch name> | <sha1> | <tag name>].
303 When RECURSIVE? is true, check out submodules as well, if any.
305 Git repositories are kept in the cache directory specified by
306 %repository-cache-directory parameter.
308 Log progress and checkout info to LOG-PORT."
309 (define (dot-git? file stat)
310 (and (string=? (basename file) ".git")
311 (or (eq? 'directory (stat:type stat))
313 ;; Submodule checkouts end up with a '.git' regular file that
314 ;; contains metadata about where their actual '.git' directory
317 (eq? 'regular (stat:type stat))))))
319 (format log-port "updating checkout of '~a'...~%" url)
322 (update-cached-checkout url
323 #:recursive? recursive?
326 (url-cache-directory url cache-directory
329 #:log-port log-port))
331 (url+commit->name url commit)))
332 (format log-port "retrieved commit ~a~%" commit)
333 (values (add-to-store store name #t "sha256" checkout
334 #:select? (negate dot-git?))
337 (define (print-git-error port key args default-printer)
339 (((? git-error? error) . _)
340 (format port (G_ "Git error: ~a~%")
341 (git-error-message error)))))
343 (set-exception-printer! 'git-error print-git-error)
347 ;;; Commit difference.
350 (define (commit-closure commit)
351 "Return the closure of COMMIT as a set."
352 (let loop ((commits (list commit))
358 (if (set-contains? visited head)
360 (loop (append (commit-parents head) tail)
361 (set-insert head visited)))))))
363 (define (commit-difference new old)
364 "Return the list of commits between NEW and OLD, where OLD is assumed to be
367 Essentially, this computes the set difference between the closure of NEW and
369 (let loop ((commits (list new))
371 (visited (commit-closure old)))
376 (if (set-contains? visited head)
377 (loop tail result visited)
378 (loop (append (commit-parents head) tail)
380 (set-insert head visited)))))))
387 ;; Representation of the "latest" checkout of a branch or a specific commit.
388 (define-record-type* <git-checkout>
389 git-checkout make-git-checkout
391 (url git-checkout-url)
392 (branch git-checkout-branch (default "master"))
393 (commit git-checkout-commit (default #f)) ;#f | tag | commit
394 (recursive? git-checkout-recursive? (default #f)))
396 (define* (latest-repository-commit* url #:key ref recursive? log-port)
397 ;; Monadic variant of 'latest-repository-commit'.
399 ;; The caller--e.g., (guix scripts build)--may not handle 'git-error' so
400 ;; translate it into '&message' conditions that we know will be properly
404 (values (latest-repository-commit store url
406 #:recursive? recursive?
409 (lambda (key error . _)
415 (format #f (G_ "cannot fetch commit ~a from ~a: ~a")
416 commit url (git-error-message error)))
418 (format #f (G_ "cannot fetch branch '~a' from ~a: ~a")
419 branch url (git-error-message error)))
421 (format #f (G_ "Git failure while fetching ~a: ~a")
422 url (git-error-message error))))))))))))
424 (define-gexp-compiler (git-checkout-compiler (checkout <git-checkout>)
426 ;; "Compile" CHECKOUT by updating the local checkout and adding it to the
429 (($ <git-checkout> url branch commit recursive?)
430 (latest-repository-commit* url
432 `(tag-or-commit . ,commit)
434 #:recursive? recursive?
435 #:log-port (current-error-port)))))
438 ;; eval: (put 'with-repository 'scheme-indent-function 2)