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2015-09-04Sync with 2.2.3Libravatar Junio C Hamano1-9/+10
2015-09-04notes: use a strbuf in add_non_noteLibravatar Jeff King1-9/+10
When we are loading a notes tree into our internal hash table, we also collect any files that are clearly non-notes. We format the name of the file into a PATH_MAX buffer, but unlike true notes (which cannot be larger than a fanned-out sha1 hash), these tree entries can be arbitrarily long, overflowing our buffer. We can fix this by switching to a strbuf. It doesn't even cost us an extra allocation, as we can simply hand ownership of the buffer over to the non-note struct. This is of moderate security interest, as you might fetch notes trees from an untrusted remote. However, we do not do so by default, so you would have to manually fetch into the notes namespace. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-24Merge branch 'jk/blame-commit-label' into maintLibravatar Junio C Hamano1-1/+1
"git blame HEAD -- missing" failed to correctly say "HEAD" when it tried to say "No such path 'missing' in HEAD". * jk/blame-commit-label: blame.c: fix garbled error message use xstrdup_or_null to replace ternary conditionals builtin/commit.c: use xstrdup_or_null instead of envdup builtin/apply.c: use xstrdup_or_null instead of null_strdup git-compat-util: add xstrdup_or_null helper
2015-01-13use xstrdup_or_null to replace ternary conditionalsLibravatar Jeff King1-1/+1
This replaces "x ? xstrdup(x) : NULL" with xstrdup_or_null(x). The change is fairly mechanical, with the exception of resolve_refdup, which can eliminate a temporary variable. There are still a few hits grepping for "?.*xstrdup", but these are of slightly different forms and cannot be converted (e.g., "x ? xstrdup(x->foo) : NULL"). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-22Merge branch 'mh/simplify-repack-without-refs'Libravatar Junio C Hamano1-1/+1
"git remote update --prune" to drop many refs has been optimized. * mh/simplify-repack-without-refs: sort_string_list(): rename to string_list_sort() prune_remote(): iterate using for_each_string_list_item() prune_remote(): rename local variable repack_without_refs(): make the refnames argument a string_list prune_remote(): sort delete_refs_list references en masse prune_remote(): initialize both delete_refs lists in a single loop prune_remote(): exit early if there are no stale references
2014-11-25sort_string_list(): rename to string_list_sort()Libravatar Michael Haggerty1-1/+1
The new name is more consistent with the names of other string_list-related functions. Suggested-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-11-12notes: empty notes should be shown by 'git log'Libravatar Johan Herland1-2/+1
If the user has gone through the trouble of explicitly adding an empty note, then "git log" should not silently skip it (as if it didn't exist). Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-05-27notes.c: rearrange xcalloc argumentsLibravatar Brian Gesiak1-3/+3
xcalloc() takes two arguments: the number of elements and their size. notes.c includes several calls to xcalloc() that pass the arguments in reverse order. Rearrange them so they are in the correct order. Signed-off-by: Brian Gesiak <modocache@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05replace {pre,suf}fixcmp() with {starts,ends}_with()Libravatar Christian Couder1-4/+4
Leaving only the function definitions and declarations so that any new topic in flight can still make use of the old functions, replace existing uses of the prefixcmp() and suffixcmp() with new API functions. The change can be recreated by mechanically applying this: $ git grep -l -e prefixcmp -e suffixcmp -- \*.c | grep -v strbuf\\.c | xargs perl -pi -e ' s|!prefixcmp\(|starts_with\(|g; s|prefixcmp\(|!starts_with\(|g; s|!suffixcmp\(|ends_with\(|g; s|suffixcmp\(|!ends_with\(|g; ' on the result of preparatory changes in this series. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-02string_list_add_refs_by_glob(): add a comment about memory managementLibravatar Michael Haggerty1-0/+4
Since string_list_add_one_ref() adds refname to the string list, but the lifetime of refname is limited, it is important that the string_list passed to string_list_add_one_ref() has strdup_strings set. Document this fact. All current callers do the right thing. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-02string_list_add_one_ref(): rename first parameter to "refname"Libravatar Michael Haggerty1-3/+3
This is the usual convention. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-11-15Merge branch 'jc/prettier-pretty-note'Libravatar Junio C Hamano1-6/+7
Emit the notes attached to the commit in "format-patch --notes" output after three-dashes. * jc/prettier-pretty-note: format-patch: add a blank line between notes and diffstat Doc User-Manual: Patch cover letter, three dashes, and --notes Doc format-patch: clarify --notes use case Doc notes: Include the format-patch --notes option Doc SubmittingPatches: Mention --notes option after "cover letter" Documentation: decribe format-patch --notes format-patch --notes: show notes after three-dashes format-patch: append --signature after notes pretty_print_commit(): do not append notes message pretty: prepare notes message at a centralized place format_note(): simplify API pretty: remove reencode_commit_message()
2012-11-15Merge branch 'mh/notes-string-list'Libravatar Junio C Hamano1-36/+25
Improve the asymptotic performance of the cat_sort_uniq notes merge strategy. * mh/notes-string-list: string_list_add_refs_from_colon_sep(): use string_list_split() notes: fix handling of colon-separated values combine_notes_cat_sort_uniq(): sort and dedup lines all at once Initialize sort_uniq_list using named constant string_list: add a function string_list_remove_empty_items()
2012-11-15Merge branch 'jc/same-encoding'Libravatar Junio C Hamano1-1/+1
Various codepaths checked if two encoding names are the same using ad-hoc code and some of them ended up asking iconv() to convert between "utf8" and "UTF-8". The former is not a valid way to spell the encoding name, but often people use it by mistake, and we equated them in some but not all codepaths. Introduce a new helper function to make these codepaths consistent. * jc/same-encoding: reencode_string(): introduce and use same_encoding() Conflicts: builtin/mailinfo.c
2012-11-08string_list_add_refs_from_colon_sep(): use string_list_split()Libravatar Michael Haggerty1-13/+8
It makes for simpler code than strbuf_split(). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Jeff King <peff@peff.net>
2012-11-08notes: fix handling of colon-separated valuesLibravatar Michael Haggerty1-2/+2
The substrings output by strbuf_split() include the ':' delimiters. When processing GIT_NOTES_DISPLAY_REF and GIT_NOTES_REWRITE_REF, strip off the delimiter character *before* checking whether the substring is empty rather than after, so that empty strings within the list are also skipped. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Jeff King <peff@peff.net>
2012-11-08combine_notes_cat_sort_uniq(): sort and dedup lines all at onceLibravatar Michael Haggerty1-22/+16
Instead of reading lines one by one and insertion-sorting them into a string_list, read all of the lines, sort them, then remove duplicates. Aside from being less code, this reduces the complexity from O(N^2) to O(N lg N) in the total number of lines. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Jeff King <peff@peff.net>
2012-11-08Initialize sort_uniq_list using named constantLibravatar Michael Haggerty1-1/+1
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Jeff King <peff@peff.net>
2012-11-04reencode_string(): introduce and use same_encoding()Libravatar Junio C Hamano1-1/+1
Callers of reencode_string() that re-encodes a string from one encoding to another all used ad-hoc way to bypass the case where the input and the output encodings are the same. Some did strcmp(), some did strcasecmp(), yet some others when converting to UTF-8 used is_encoding_utf8(). Introduce same_encoding() helper function to make these callers use the same logic. Notably, is_encoding_utf8() has a work-around for common misconfiguration to use "utf8" to name UTF-8 encoding, which does not match "UTF-8" hence strcasecmp() would not consider the same. Make use of it in this helper function. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-17format_note(): simplify APILibravatar Junio C Hamano1-6/+7
We either stuff the notes message without modification for %N userformat, or format it for human consumption. Using two bits is an overkill that does not benefit anybody. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-15notes.c: mark a private file-scope symbol as staticLibravatar Junio C Hamano1-2/+12
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-22Do not use C++-style commentsLibravatar Michael Haggerty1-1/+1
Detected by "gcc -std=iso9899:1990 ...". This patch applies against "maint". Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-29notes: refactor display notes default handlingLibravatar Jeff King1-1/+2
This is in preparation for more notes-related revision command-line options. The "suppress_default_notes" option is renamed to "use_default_notes", and is now a tri-state with values less than one indicating "not set". If the value is "not set", then we show default refs if and only if no other refs were given. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-29notes: refactor display notes extra refs fieldLibravatar Jeff King1-2/+2
There's no need to use an extra pointer, which just ends up leaking memory. The fact that the list is empty tells us the same thing. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-29notes: make expand_notes_ref globally accessibleLibravatar Jeff King1-0/+10
This function is useful for other commands besides "git notes" which want to let users refer to notes by their shorthand name. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-08Merge branch 'jh/notes-merge'Libravatar Junio C Hamano1-92/+180
* jh/notes-merge: (23 commits) Provide 'git merge --abort' as a synonym to 'git reset --merge' cmd_merge(): Parse options before checking MERGE_HEAD Provide 'git notes get-ref' to easily retrieve current notes ref git notes merge: Add testcases for merging notes trees at different fanouts git notes merge: Add another auto-resolving strategy: "cat_sort_uniq" git notes merge: --commit should fail if underlying notes ref has moved git notes merge: List conflicting notes in notes merge commit message git notes merge: Manual conflict resolution, part 2/2 git notes merge: Manual conflict resolution, part 1/2 Documentation: Preliminary docs on 'git notes merge' git notes merge: Add automatic conflict resolvers (ours, theirs, union) git notes merge: Handle real, non-conflicting notes merges builtin/notes.c: Refactor creation of notes commits. git notes merge: Initial implementation handling trivial merges only builtin/notes.c: Split notes ref DWIMmery into a separate function notes.c: Use two newlines (instead of one) when concatenating notes (trivial) t3303: Indent with tabs instead of spaces for consistency notes.h/c: Propagate combine_notes_fn return value to add_note() and beyond notes.h/c: Allow combine_notes functions to remove notes notes.c: Reorder functions in preparation for next commit ... Conflicts: builtin.h
2010-11-17git notes merge: Add another auto-resolving strategy: "cat_sort_uniq"Libravatar Johan Herland1-0/+76
This new strategy is similar to "concatenate", but in addition to concatenating the two note candidates, this strategy sorts the resulting lines, and removes duplicate lines from the result. This is equivalent to applying the "cat | sort | uniq" shell pipeline to the two note candidates. This strategy is useful if the notes follow a line-based format where one wants to avoid duplicate lines in the merge result. Note that if either of the note candidates contain duplicate lines _prior_ to the merge, these will also be removed by this merge strategy. The patch also contains tests and documentation for the new strategy. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-17notes.c: Use two newlines (instead of one) when concatenating notesLibravatar Johan Herland1-3/+4
When using combine_notes_concatenate() to concatenate notes, it currently ensures exactly one newline character between the given notes. However, when using builtin/notes.c:create_note() to concatenate notes (e.g. by 'git notes append'), it adds a newline character to the trailing newline of the preceding notes object, thus resulting in _two_ newlines (aka. a blank line) separating contents of the two notes. This patch brings combine_notes_concatenate() into consistency with builtin/notes.c:create_note(), by ensuring exactly _two_ newline characters between concatenated notes. The patch also changes a few notes-related selftests accordingly. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-17notes.h/c: Propagate combine_notes_fn return value to add_note() and beyondLibravatar Johan Herland1-27/+28
The combine_notes_fn functions uses a non-zero return value to indicate failure. However, this return value was converted to a call to die() in note_tree_insert(). Instead, propagate this return value out to add_note(), and return it from there to enable the caller to handle errors appropriately. Existing add_note() callers are updated to die() upon failure, thus preserving the current behaviour. The only exceptions are copy_note() and notes_cache_put() where we are able to propagate the add_note() return value instead. This patch has been improved by the following contributions: - Jonathan Nieder: Future-proof by always checking add_note() return value - Jonathan Nieder: Improve clarity of final if-condition in note_tree_insert() Thanks-to: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-10notes.h/c: Allow combine_notes functions to remove notesLibravatar Johan Herland1-1/+11
Allow combine_notes functions to request that a note be removed, by setting the resulting note SHA1 to null_sha1 (0000000...). For consistency, also teach note_tree_insert() to skip insertion of an empty note (a note with entry->val_sha1 equal to null_sha1) when there is no note to combine it with. In general, an empty note (null_sha1) is treated identically to no note at all, but when adding an empty note where there already exists a non-empty note, we allow the combine_notes function to potentially record a new/changed note. Document this behaviour, and clearly specify how combine_notes functions are expected to handle null_sha1 in input. Before this patch, storing null_sha1s in the notes tree were silently allowed, causing an invalid notes tree (referring to blobs with null_sha1) to be produced by write_notes_tree(). Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-10notes.c: Reorder functions in preparation for next commitLibravatar Johan Herland1-73/+73
This patch introduces no functional change. It consists solely of reordering functions in notes.c to avoid use-before-declaration errors after applying the next commit in this series. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-10notes.h: Make default_notes_ref() available in notes APILibravatar Johan Herland1-1/+1
Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-10notes.c: Hexify SHA1 in die() message from init_notes()Libravatar Johan Herland1-1/+1
Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-31notes: Don't create (empty) commit when removing non-existing notesLibravatar Johan Herland1-4/+10
Extend remove_note() in the notes API to return whether or not a note was actually removed. Use this in 'git notes remove' to skip the creation of a notes commit when no notes were actually removed. Also add a test illustrating the change in behavior. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-07-05Convert the users of for_each_string_list to for_each_string_list_item macroLibravatar Alex Riesen1-32/+14
The rule for selecting the candidates for conversion is: if the callback function returns only 0 (the condition for for_each_string_list to exit early), than it can be safely converted to the macro. A notable exception are the callers in builtin/remote.c. If converted, the readability in the file will suffer greately. Besides, the code is not very performance critical (at the moment, at least): it does output formatting of the list of remotes. Signed-off-by: Alex Riesen <raa.lkml@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-30Merge branch 'jp/string-list-api-cleanup'Libravatar Junio C Hamano1-6/+6
* jp/string-list-api-cleanup: string_list: Fix argument order for string_list_append string_list: Fix argument order for string_list_lookup string_list: Fix argument order for string_list_insert_at_index string_list: Fix argument order for string_list_insert string_list: Fix argument order for for_each_string_list string_list: Fix argument order for print_string_list
2010-06-28Merge branch 'maint'Libravatar Junio C Hamano1-1/+1
* maint: Update draft release notes to 1.7.1.1 notes: Initialise variable to appease gcc notes: check number of parameters to "git notes copy"
2010-06-28notes: Initialise variable to appease gccLibravatar Ramsay Jones1-1/+1
gcc version 3.4.4 thinks that the 'cmp' variable could be used while uninitialised and complains thus: notes.c: In function `write_each_non_note_until': notes.c:719: warning: 'cmp' might be used uninitialized in \ this function Note that gcc versions 4.1.2 and 4.4.0 do not issue this warning. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-27string_list: Fix argument order for string_list_appendLibravatar Julian Phillips1-3/+3
Update the definition and callers of string_list_append to use the string_list as the first argument. This helps make the string_list API easier to use by being more consistent. Signed-off-by: Julian Phillips <julian@quantumfyre.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-27string_list: Fix argument order for for_each_string_listLibravatar Julian Phillips1-3/+3
Update the definition and callers of for_each_string_list to use the string_list as the first argument. This helps make the string_list API easier to use by being more consistent. Signed-off-by: Julian Phillips <julian@quantumfyre.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-19notes: dry-run and verbose options for pruneLibravatar Michael J Gruber1-2/+5
Introduce -n and -v options for "git notes prune" in complete analogy to "git prune" so that one can check for dangling notes easily. The output is a list of names of objects whose notes would be resp. are removed so that one can check the object ("git show sha1") as well as the note ("git notes show sha1"). Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-03-24Merge branch 'tr/notes-display'Libravatar Junio C Hamano1-7/+183
* tr/notes-display: git-notes(1): add a section about the meaning of history notes: track whether notes_trees were changed at all notes: add shorthand --ref to override GIT_NOTES_REF commit --amend: copy notes to the new commit rebase: support automatic notes copying notes: implement helpers needed for note copying during rewrite notes: implement 'git notes copy --stdin' rebase -i: invoke post-rewrite hook rebase: invoke post-rewrite hook commit --amend: invoke post-rewrite hook Documentation: document post-rewrite hook Support showing notes from more than one notes tree test-lib: unset GIT_NOTES_REF to stop it from influencing tests Conflicts: git-am.sh refs.c
2010-03-20notes.c: remove inappropriate call to returnLibravatar Brandon Casey1-1/+1
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-03-12notes: track whether notes_trees were changed at allLibravatar Thomas Rast1-0/+3
Currently, the notes copying is a bit wasteful since it always creates new trees, even if no notes were copied at all. Teach add_note() and remove_note() to flag the affected notes tree as changed ('dirty'). Then teach builtin/notes.c to use this knowledge and avoid committing trees that weren't changed. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-03-12notes: implement 'git notes copy --stdin'Libravatar Thomas Rast1-0/+18
This implements a mass-copy command that takes a sequence of lines in the format <from-sha1> SP <to-sha1> [ SP <rest> ] LF on stdin, and copies each <from-sha1>'s notes to the <to-sha1>. The <rest> is ignored. The intent, of course, is that this can read the same input that the 'post-rewrite' hook gets. The copy_note() function is exposed for everyone's and in particular the next commit's use. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-03-12Support showing notes from more than one notes treeLibravatar Thomas Rast1-7/+162
With this patch, you can set notes.displayRef to a glob that points at your favourite notes refs, e.g., [notes] displayRef = refs/notes/* Then git-log and friends will show notes from all trees. Thanks to Junio C Hamano for lots of feedback, which greatly influenced the design of the entire series and this commit in particular. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Acked-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-24notes: fix malformed tree entryLibravatar Junio C Hamano1-2/+2
The mode bits for entries in a tree object should be an octal number with minimum number of digits. Do not pad it with 0 to the left. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-13Notes API: prune_notes(): Prune notes that belong to non-existing objectsLibravatar Johan Herland1-0/+39
When an object is made unreachable by Git, any notes that annotate that object are not automagically made unreachable, since all notes are always trivially reachable from a notes ref. In order to remove notes for non-existing objects, we therefore need to add functionality for traversing the notes tree and explicitly removing references to notes that annotate non-reachable objects. Thus the notes objects themselves also become unreachable, and are removed by a later garbage collect. prune_notes() performs this traversal (by using for_each_note() internally), and removes the notes in question from the notes tree. Note that the effect of prune_notes() is not persistent unless a subsequent call to write_notes_tree() is made. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-13Teach notes code to properly preserve non-notes in the notes treeLibravatar Johan Herland1-39/+180
The note tree structure allows for non-note entries to coexist with note entries in a notes tree. Although we certainly expect there to be very few non-notes in a notes tree, we should still support them to a certain degree. This patch teaches the notes code to preserve non-notes when updating the notes tree with write_notes_tree(). Non-notes are not affected by fanout restructuring. For non-notes to be handled correctly, we can no longer allow subtree entries that do not match the fanout structure produced by the notes code itself. This means that fanouts like 4/36, 6/34, 8/32, 4/4/32, etc. are no longer recognized as note subtrees; only 2-based fanouts are allowed (2/38, 2/2/36, 2/2/2/34, etc.). Since the notes code has never at any point _produced_ non-2-based fanouts, it is highly unlikely that this change will cause problems for anyone. The patch also adds some tests verifying the correct handling of non-notes in a notes tree. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-13Refactor notes concatenation into a flexible interface for combining notesLibravatar Johan Herland1-58/+80
When adding a note to an object that already has an existing note, the current solution is to concatenate the contents of the two notes. However, the caller may instead wish to _overwrite_ the existing note with the new note, or maybe even _ignore_ the new note, and keep the existing one. There might also be other ways of combining notes that are only known to the caller. Therefore, instead of unconditionally concatenating notes, we let the caller specify how to combine notes, by passing in a pointer to a function for combining notes. The caller may choose to implement its own function for notes combining, but normally one of the following three conveniently supplied notes combination functions will be sufficient: - combine_notes_concatenate() combines the two notes by appending the contents of the new note to the contents of the existing note. - combine_notes_overwrite() replaces the existing note with the new note. - combine_notes_ignore() keeps the existing note, and ignores the new note. A combine_notes function can be passed to init_notes() to choose a default combine_notes function for that notes tree. If NULL is given, the notes tree falls back to combine_notes_concatenate() as the ultimate default. A combine_notes function can also be passed directly to add_note(), to control the notes combining behaviour for a note addition in particular. If NULL is passed, the combine_notes function registered for the given notes tree is used. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>