prepare the builtins for a libified merge_recursive()

Previously, callers of merge_trees() or merge_recursive() expected that
code to die() with an error message. This used to be okay because we
called those commands from scripts, and had a chance to print out a
message in case the command failed fatally (read: with exit code 128).

As scripting incurs its own set of problems (portability, speed,
idiosyncrasies of different shells, limited data structures leading to
inefficient code), we are converting more and more of these scripts into
builtins, using library functions directly.

We already tried to use merge_recursive() directly in the builtin
git-am, for example. Unfortunately, we had to roll it back temporarily
because some of the code in merge-recursive.c still deemed it okay to
call die(), when the builtin am code really wanted to print out a useful
advice after the merge failed fatally. In the next commits, we want to
fix that.

The code touched by this commit expected merge_trees() to die() with
some useful message when there is an error condition, but merge_trees()
is going to be improved by converting all die() calls to return error()
instead (i.e. return value -1 after printing out the message as before),
so that the caller can react more flexibly.

This is a step to prepare for the version of merge_trees() that no
longer dies,  even if we just imitate the previous behavior by calling
exit(128): this is what callers of e.g. `git merge` have come to expect.

Note that the callers of the sequencer (revert and cherry-pick) already
fail fast even for the return value -1; The only difference is that they
now get a chance to say "<command> failed".

A caller of merge_trees() might want handle error messages themselves
(or even suppress them). As this patch is already complex enough, we
leave that change for a later patch.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
3 files changed
tree: 31a63632ae8070df7b557b0d6ec2e7ea416c825f
  1. block-sha1/
  2. builtin/
  3. ci/
  4. compat/
  5. contrib/
  6. Documentation/
  7. ewah/
  8. git-gui/
  9. gitk-git/
  10. gitweb/
  11. mergetools/
  12. perl/
  13. po/
  14. ppc/
  15. refs/
  16. t/
  17. templates/
  18. vcs-svn/
  19. xdiff/
  20. .gitattributes
  21. .gitignore
  22. .mailmap
  23. .travis.yml
  24. abspath.c
  25. aclocal.m4
  26. advice.c
  27. advice.h
  28. alias.c
  29. alloc.c
  30. archive-tar.c
  31. archive-zip.c
  32. archive.c
  33. archive.h
  34. argv-array.c
  35. argv-array.h
  36. attr.c
  37. attr.h
  38. base85.c
  39. bisect.c
  40. bisect.h
  41. blob.c
  42. blob.h
  43. branch.c
  44. branch.h
  45. builtin.h
  46. bulk-checkin.c
  47. bulk-checkin.h
  48. bundle.c
  49. bundle.h
  50. cache-tree.c
  51. cache-tree.h
  52. cache.h
  53. check-builtins.sh
  54. check-racy.c
  55. check_bindir
  56. color.c
  57. color.h
  58. column.c
  59. column.h
  60. combine-diff.c
  61. command-list.txt
  62. commit-slab.h
  63. commit.c
  64. commit.h
  65. common-main.c
  66. config.c
  67. config.mak.in
  68. config.mak.uname
  69. configure.ac
  70. connect.c
  71. connect.h
  72. connected.c
  73. connected.h
  74. convert.c
  75. convert.h
  76. copy.c
  77. COPYING
  78. credential-cache--daemon.c
  79. credential-cache.c
  80. credential-store.c
  81. credential.c
  82. credential.h
  83. csum-file.c
  84. csum-file.h
  85. ctype.c
  86. daemon.c
  87. date.c
  88. decorate.c
  89. decorate.h
  90. delta.h
  91. diff-delta.c
  92. diff-lib.c
  93. diff-no-index.c
  94. diff.c
  95. diff.h
  96. diffcore-break.c
  97. diffcore-delta.c
  98. diffcore-order.c
  99. diffcore-pickaxe.c
  100. diffcore-rename.c
  101. diffcore.h
  102. dir-iterator.c
  103. dir-iterator.h
  104. dir.c
  105. dir.h
  106. editor.c
  107. entry.c
  108. environment.c
  109. exec_cmd.c
  110. exec_cmd.h
  111. fast-import.c
  112. fetch-pack.c
  113. fetch-pack.h
  114. fmt-merge-msg.h
  115. fsck.c
  116. fsck.h
  117. generate-cmdlist.sh
  118. gettext.c
  119. gettext.h
  120. git-add--interactive.perl
  121. git-archimport.perl
  122. git-bisect.sh
  123. git-compat-util.h
  124. git-cvsexportcommit.perl
  125. git-cvsimport.perl
  126. git-cvsserver.perl
  127. git-difftool--helper.sh
  128. git-difftool.perl
  129. git-filter-branch.sh
  130. git-instaweb.sh
  131. git-merge-octopus.sh
  132. git-merge-one-file.sh
  133. git-merge-resolve.sh
  134. git-mergetool--lib.sh
  135. git-mergetool.sh
  136. git-p4.py
  137. git-parse-remote.sh
  138. git-quiltimport.sh
  139. git-rebase--am.sh
  140. git-rebase--interactive.sh
  141. git-rebase--merge.sh
  142. git-rebase.sh
  143. git-relink.perl
  144. git-remote-testgit.sh
  145. git-request-pull.sh
  146. git-send-email.perl
  147. git-sh-i18n.sh
  148. git-sh-setup.sh
  149. git-stash.sh
  150. git-submodule.sh
  151. git-svn.perl
  152. GIT-VERSION-GEN
  153. git-web--browse.sh
  154. git.c
  155. git.rc
  156. gpg-interface.c
  157. gpg-interface.h
  158. graph.c
  159. graph.h
  160. grep.c
  161. grep.h
  162. hashmap.c
  163. hashmap.h
  164. help.c
  165. help.h
  166. hex.c
  167. http-backend.c
  168. http-fetch.c
  169. http-push.c
  170. http-walker.c
  171. http.c
  172. http.h
  173. ident.c
  174. imap-send.c
  175. INSTALL
  176. iterator.h
  177. khash.h
  178. kwset.c
  179. kwset.h
  180. levenshtein.c
  181. levenshtein.h
  182. LGPL-2.1
  183. line-log.c
  184. line-log.h
  185. line-range.c
  186. line-range.h
  187. list-objects.c
  188. list-objects.h
  189. ll-merge.c
  190. ll-merge.h
  191. lockfile.c
  192. lockfile.h
  193. log-tree.c
  194. log-tree.h
  195. mailinfo.c
  196. mailinfo.h
  197. mailmap.c
  198. mailmap.h
  199. Makefile
  200. match-trees.c
  201. merge-blobs.c
  202. merge-blobs.h
  203. merge-recursive.c
  204. merge-recursive.h
  205. merge.c
  206. mergesort.c
  207. mergesort.h
  208. name-hash.c
  209. notes-cache.c
  210. notes-cache.h
  211. notes-merge.c
  212. notes-merge.h
  213. notes-utils.c
  214. notes-utils.h
  215. notes.c
  216. notes.h
  217. object.c
  218. object.h
  219. pack-bitmap-write.c
  220. pack-bitmap.c
  221. pack-bitmap.h
  222. pack-check.c
  223. pack-objects.c
  224. pack-objects.h
  225. pack-revindex.c
  226. pack-revindex.h
  227. pack-write.c
  228. pack.h
  229. pager.c
  230. parse-options-cb.c
  231. parse-options.c
  232. parse-options.h
  233. patch-delta.c
  234. patch-ids.c
  235. patch-ids.h
  236. path.c
  237. pathspec.c
  238. pathspec.h
  239. pkt-line.c
  240. pkt-line.h
  241. preload-index.c
  242. pretty.c
  243. prio-queue.c
  244. prio-queue.h
  245. progress.c
  246. progress.h
  247. prompt.c
  248. prompt.h
  249. quote.c
  250. quote.h
  251. reachable.c
  252. reachable.h
  253. read-cache.c
  254. README.md
  255. ref-filter.c
  256. ref-filter.h
  257. reflog-walk.c
  258. reflog-walk.h
  259. refs.c
  260. refs.h
  261. remote-curl.c
  262. remote-testsvn.c
  263. remote.c
  264. remote.h
  265. replace_object.c
  266. rerere.c
  267. rerere.h
  268. resolve-undo.c
  269. resolve-undo.h
  270. revision.c
  271. revision.h
  272. run-command.c
  273. run-command.h
  274. send-pack.c
  275. send-pack.h
  276. sequencer.c
  277. sequencer.h
  278. server-info.c
  279. setup.c
  280. sh-i18n--envsubst.c
  281. sha1-array.c
  282. sha1-array.h
  283. sha1-lookup.c
  284. sha1-lookup.h
  285. sha1_file.c
  286. sha1_name.c
  287. shallow.c
  288. shell.c
  289. shortlog.h
  290. show-index.c
  291. sideband.c
  292. sideband.h
  293. sigchain.c
  294. sigchain.h
  295. split-index.c
  296. split-index.h
  297. strbuf.c
  298. strbuf.h
  299. streaming.c
  300. streaming.h
  301. string-list.c
  302. string-list.h
  303. submodule-config.c
  304. submodule-config.h
  305. submodule.c
  306. submodule.h
  307. symlinks.c
  308. tag.c
  309. tag.h
  310. tar.h
  311. tempfile.c
  312. tempfile.h
  313. thread-utils.c
  314. thread-utils.h
  315. trace.c
  316. trace.h
  317. trailer.c
  318. trailer.h
  319. transport-helper.c
  320. transport.c
  321. transport.h
  322. tree-diff.c
  323. tree-walk.c
  324. tree-walk.h
  325. tree.c
  326. tree.h
  327. unicode_width.h
  328. unimplemented.sh
  329. unix-socket.c
  330. unix-socket.h
  331. unpack-trees.c
  332. unpack-trees.h
  333. update_unicode.sh
  334. upload-pack.c
  335. url.c
  336. url.h
  337. urlmatch.c
  338. urlmatch.h
  339. usage.c
  340. userdiff.c
  341. userdiff.h
  342. utf8.c
  343. utf8.h
  344. varint.c
  345. varint.h
  346. version.c
  347. version.h
  348. versioncmp.c
  349. walker.c
  350. walker.h
  351. wildmatch.c
  352. wildmatch.h
  353. worktree.c
  354. worktree.h
  355. wrap-for-bin.sh
  356. wrapper.c
  357. write_or_die.c
  358. ws.c
  359. wt-status.c
  360. wt-status.h
  361. xdiff-interface.c
  362. xdiff-interface.h
  363. zlib.c
README.md

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 http://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-.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 http://news.gmane.org/gmane.comp.version-control.git/, http://marc.info/?l=git and other archival sites.

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