commit-graph: introduce 'get_bloom_filter_settings()'

Many places in the code often need a pointer to the commit-graph's
'struct bloom_filter_settings', in which case they often take the value
from the top-most commit-graph.

In the non-split case, this works as expected. In the split case,
however, things get a little tricky. Not all layers in a chain of
incremental commit-graphs are required to themselves have Bloom data,
and so whether or not some part of the code uses Bloom filters depends
entirely on whether or not the top-most level of the commit-graph chain
has Bloom filters.

This has been the behavior since Bloom filters were introduced, and has
been codified into the tests since a759bfa9ee (t4216: add end to end
tests for git log with Bloom filters, 2020-04-06). In fact, t4216.130
requires that Bloom filters are not used in exactly the case described
earlier.

There is no reason that this needs to be the case, since it is perfectly
valid for commits in an earlier layer to have Bloom filters when commits
in a newer layer do not.

Since Bloom settings are guaranteed in practice to be the same for any
layer in a chain that has Bloom data, it is sufficient to traverse the
'->base_graph' pointer until either (1) a non-null 'struct
bloom_filter_settings *' is found, or (2) until we are at the root of
the commit-graph chain.

Introduce a 'get_bloom_filter_settings()' function that does just this,
and use it instead of purely dereferencing the top-most graph's
'->bloom_filter_settings' pointer.

While we're at it, add an additional test in t5324 to guard against code
in the commit-graph writing machinery that doesn't correctly handle a
NULL 'struct bloom_filter *'.

Co-authored-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
7 files changed
tree: 8260653066ec8e0b14769325552b180e1f68c24d
  1. .github/
  2. block-sha1/
  3. builtin/
  4. ci/
  5. compat/
  6. contrib/
  7. Documentation/
  8. ewah/
  9. git-gui/
  10. gitk-git/
  11. gitweb/
  12. mergetools/
  13. negotiator/
  14. perl/
  15. po/
  16. ppc/
  17. refs/
  18. sha1dc/
  19. sha256/
  20. t/
  21. templates/
  22. trace2/
  23. vcs-svn/
  24. xdiff/
  25. .cirrus.yml
  26. .clang-format
  27. .editorconfig
  28. .gitattributes
  29. .gitignore
  30. .gitmodules
  31. .mailmap
  32. .travis.yml
  33. .tsan-suppressions
  34. abspath.c
  35. aclocal.m4
  36. add-interactive.c
  37. add-interactive.h
  38. add-patch.c
  39. advice.c
  40. advice.h
  41. alias.c
  42. alias.h
  43. alloc.c
  44. alloc.h
  45. apply.c
  46. apply.h
  47. archive-tar.c
  48. archive-zip.c
  49. archive.c
  50. archive.h
  51. argv-array.c
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  53. attr.c
  54. attr.h
  55. banned.h
  56. base85.c
  57. bisect.c
  58. bisect.h
  59. blame.c
  60. blame.h
  61. blob.c
  62. blob.h
  63. bloom.c
  64. bloom.h
  65. branch.c
  66. branch.h
  67. bugreport.c
  68. builtin.h
  69. bulk-checkin.c
  70. bulk-checkin.h
  71. bundle.c
  72. bundle.h
  73. cache-tree.c
  74. cache-tree.h
  75. cache.h
  76. chdir-notify.c
  77. chdir-notify.h
  78. check-builtins.sh
  79. check_bindir
  80. checkout.c
  81. checkout.h
  82. CODE_OF_CONDUCT.md
  83. color.c
  84. color.h
  85. column.c
  86. column.h
  87. combine-diff.c
  88. command-list.txt
  89. commit-graph.c
  90. commit-graph.h
  91. commit-reach.c
  92. commit-reach.h
  93. commit-slab-decl.h
  94. commit-slab-impl.h
  95. commit-slab.h
  96. commit.c
  97. commit.h
  98. common-main.c
  99. config.c
  100. config.h
  101. config.mak.dev
  102. config.mak.in
  103. config.mak.uname
  104. configure.ac
  105. connect.c
  106. connect.h
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  109. convert.c
  110. convert.h
  111. copy.c
  112. COPYING
  113. credential-cache--daemon.c
  114. credential-cache.c
  115. credential-store.c
  116. credential.c
  117. credential.h
  118. csum-file.c
  119. csum-file.h
  120. ctype.c
  121. daemon.c
  122. date.c
  123. decorate.c
  124. decorate.h
  125. delta-islands.c
  126. delta-islands.h
  127. delta.h
  128. detect-compiler
  129. diff-delta.c
  130. diff-lib.c
  131. diff-no-index.c
  132. diff.c
  133. diff.h
  134. diffcore-break.c
  135. diffcore-delta.c
  136. diffcore-order.c
  137. diffcore-pickaxe.c
  138. diffcore-rename.c
  139. diffcore.h
  140. dir-iterator.c
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  142. dir.c
  143. dir.h
  144. editor.c
  145. entry.c
  146. environment.c
  147. exec-cmd.c
  148. exec-cmd.h
  149. fast-import.c
  150. fetch-negotiator.c
  151. fetch-negotiator.h
  152. fetch-pack.c
  153. fetch-pack.h
  154. fmt-merge-msg.c
  155. fmt-merge-msg.h
  156. fsck.c
  157. fsck.h
  158. fsmonitor.c
  159. fsmonitor.h
  160. fuzz-commit-graph.c
  161. fuzz-pack-headers.c
  162. fuzz-pack-idx.c
  163. generate-cmdlist.sh
  164. generate-configlist.sh
  165. gettext.c
  166. gettext.h
  167. git-add--interactive.perl
  168. git-archimport.perl
  169. git-bisect.sh
  170. git-compat-util.h
  171. git-cvsexportcommit.perl
  172. git-cvsimport.perl
  173. git-cvsserver.perl
  174. git-difftool--helper.sh
  175. git-filter-branch.sh
  176. git-instaweb.sh
  177. git-merge-octopus.sh
  178. git-merge-one-file.sh
  179. git-merge-resolve.sh
  180. git-mergetool--lib.sh
  181. git-mergetool.sh
  182. git-p4.py
  183. git-parse-remote.sh
  184. git-quiltimport.sh
  185. git-rebase--preserve-merges.sh
  186. git-request-pull.sh
  187. git-send-email.perl
  188. git-sh-i18n.sh
  189. git-sh-setup.sh
  190. git-submodule.sh
  191. git-svn.perl
  192. GIT-VERSION-GEN
  193. git-web--browse.sh
  194. git.c
  195. git.rc
  196. gpg-interface.c
  197. gpg-interface.h
  198. graph.c
  199. graph.h
  200. grep.c
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  202. hash.h
  203. hashmap.c
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  205. help.c
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  207. hex.c
  208. http-backend.c
  209. http-fetch.c
  210. http-push.c
  211. http-walker.c
  212. http.c
  213. http.h
  214. ident.c
  215. imap-send.c
  216. INSTALL
  217. interdiff.c
  218. interdiff.h
  219. iterator.h
  220. json-writer.c
  221. json-writer.h
  222. khash.h
  223. kwset.c
  224. kwset.h
  225. levenshtein.c
  226. levenshtein.h
  227. LGPL-2.1
  228. line-log.c
  229. line-log.h
  230. line-range.c
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  232. linear-assignment.c
  233. linear-assignment.h
  234. list-objects-filter-options.c
  235. list-objects-filter-options.h
  236. list-objects-filter.c
  237. list-objects-filter.h
  238. list-objects.c
  239. list-objects.h
  240. list.h
  241. ll-merge.c
  242. ll-merge.h
  243. lockfile.c
  244. lockfile.h
  245. log-tree.c
  246. log-tree.h
  247. ls-refs.c
  248. ls-refs.h
  249. mailinfo.c
  250. mailinfo.h
  251. mailmap.c
  252. mailmap.h
  253. Makefile
  254. match-trees.c
  255. mem-pool.c
  256. mem-pool.h
  257. merge-blobs.c
  258. merge-blobs.h
  259. merge-recursive.c
  260. merge-recursive.h
  261. merge.c
  262. mergesort.c
  263. mergesort.h
  264. midx.c
  265. midx.h
  266. name-hash.c
  267. notes-cache.c
  268. notes-cache.h
  269. notes-merge.c
  270. notes-merge.h
  271. notes-utils.c
  272. notes-utils.h
  273. notes.c
  274. notes.h
  275. object-store.h
  276. object.c
  277. object.h
  278. oid-array.c
  279. oid-array.h
  280. oidmap.c
  281. oidmap.h
  282. oidset.c
  283. oidset.h
  284. pack-bitmap-write.c
  285. pack-bitmap.c
  286. pack-bitmap.h
  287. pack-check.c
  288. pack-objects.c
  289. pack-objects.h
  290. pack-revindex.c
  291. pack-revindex.h
  292. pack-write.c
  293. pack.h
  294. packfile.c
  295. packfile.h
  296. pager.c
  297. parse-options-cb.c
  298. parse-options.c
  299. parse-options.h
  300. patch-delta.c
  301. patch-ids.c
  302. patch-ids.h
  303. path.c
  304. path.h
  305. pathspec.c
  306. pathspec.h
  307. pkt-line.c
  308. pkt-line.h
  309. preload-index.c
  310. pretty.c
  311. pretty.h
  312. prio-queue.c
  313. prio-queue.h
  314. progress.c
  315. progress.h
  316. promisor-remote.c
  317. promisor-remote.h
  318. prompt.c
  319. prompt.h
  320. protocol.c
  321. protocol.h
  322. prune-packed.c
  323. prune-packed.h
  324. quote.c
  325. quote.h
  326. range-diff.c
  327. range-diff.h
  328. reachable.c
  329. reachable.h
  330. read-cache.c
  331. README.md
  332. rebase-interactive.c
  333. rebase-interactive.h
  334. rebase.c
  335. rebase.h
  336. ref-filter.c
  337. ref-filter.h
  338. reflog-walk.c
  339. reflog-walk.h
  340. refs.c
  341. refs.h
  342. refspec.c
  343. refspec.h
  344. remote-curl.c
  345. remote-testsvn.c
  346. remote.c
  347. remote.h
  348. replace-object.c
  349. replace-object.h
  350. repo-settings.c
  351. repository.c
  352. repository.h
  353. rerere.c
  354. rerere.h
  355. reset.c
  356. reset.h
  357. resolve-undo.c
  358. resolve-undo.h
  359. revision.c
  360. revision.h
  361. run-command.c
  362. run-command.h
  363. send-pack.c
  364. send-pack.h
  365. sequencer.c
  366. sequencer.h
  367. serve.c
  368. serve.h
  369. server-info.c
  370. setup.c
  371. sh-i18n--envsubst.c
  372. sha1-file.c
  373. sha1-lookup.c
  374. sha1-lookup.h
  375. sha1-name.c
  376. sha1dc_git.c
  377. sha1dc_git.h
  378. shallow.c
  379. shallow.h
  380. shell.c
  381. shortlog.h
  382. sideband.c
  383. sideband.h
  384. sigchain.c
  385. sigchain.h
  386. split-index.c
  387. split-index.h
  388. stable-qsort.c
  389. strbuf.c
  390. strbuf.h
  391. streaming.c
  392. streaming.h
  393. string-list.c
  394. string-list.h
  395. sub-process.c
  396. sub-process.h
  397. submodule-config.c
  398. submodule-config.h
  399. submodule.c
  400. submodule.h
  401. symlinks.c
  402. tag.c
  403. tag.h
  404. tar.h
  405. tempfile.c
  406. tempfile.h
  407. thread-utils.c
  408. thread-utils.h
  409. tmp-objdir.c
  410. tmp-objdir.h
  411. trace.c
  412. trace.h
  413. trace2.c
  414. trace2.h
  415. trailer.c
  416. trailer.h
  417. transport-helper.c
  418. transport-internal.h
  419. transport.c
  420. transport.h
  421. tree-diff.c
  422. tree-walk.c
  423. tree-walk.h
  424. tree.c
  425. tree.h
  426. unicode-width.h
  427. unimplemented.sh
  428. unix-socket.c
  429. unix-socket.h
  430. unpack-trees.c
  431. unpack-trees.h
  432. upload-pack.c
  433. upload-pack.h
  434. url.c
  435. url.h
  436. urlmatch.c
  437. urlmatch.h
  438. usage.c
  439. userdiff.c
  440. userdiff.h
  441. utf8.c
  442. utf8.h
  443. varint.c
  444. varint.h
  445. version.c
  446. version.h
  447. versioncmp.c
  448. walker.c
  449. walker.h
  450. wildmatch.c
  451. wildmatch.h
  452. worktree.c
  453. worktree.h
  454. wrap-for-bin.sh
  455. wrapper.c
  456. write-or-die.c
  457. ws.c
  458. wt-status.c
  459. wt-status.h
  460. xdiff-interface.c
  461. xdiff-interface.h
  462. zlib.c
README.md

Build status

Git - fast, scalable, distributed revision control system

Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.

Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.

Please read the file INSTALL for installation instructions.

Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.

See Documentation/gittutorial.txt to get started, then see Documentation/giteveryday.txt for a useful minimum set of commands, and Documentation/git-<commandname>.txt for documentation of each command. If git has been correctly installed, then the tutorial can also be read with man gittutorial or git help tutorial, and the documentation of each command with man git-<commandname> or git help <commandname>.

CVS users may also want to read Documentation/gitcvs-migration.txt (man gitcvs-migration or git help cvs-migration if git is installed).

The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just “subscribe git” in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.

Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.

The maintainer frequently sends the “What's cooking” reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.

The name “git” was given by Linus Torvalds when he wrote the very first version. He described the tool as “the stupid content tracker” and the name as (depending on your mood):

  • random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of “get” may or may not be relevant.
  • stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
  • “global information tracker”: you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
  • “goddamn idiotic truckload of sh*t”: when it breaks