rebase --root: fix amending root commit messages
[git.git] / notes.h
blob0433f45db55b5b807abcd633f507e9c75324d4e6
1 #ifndef NOTES_H
2 #define NOTES_H
4 #include "string-list.h"
6 /*
7 * Function type for combining two notes annotating the same object.
9 * When adding a new note annotating the same object as an existing note, it is
10 * up to the caller to decide how to combine the two notes. The decision is
11 * made by passing in a function of the following form. The function accepts
12 * two object_ids -- of the existing note and the new note, respectively. The
13 * function then combines the notes in whatever way it sees fit, and writes the
14 * resulting oid into the first argument (cur_oid). A non-zero return
15 * value indicates failure.
17 * The two given object_ids shall both be non-NULL and different from each
18 * other. Either of them (but not both) may be == null_oid, which indicates an
19 * empty/non-existent note. If the resulting oid (cur_oid) is == null_oid,
20 * the note will be removed from the notes tree.
22 * The default combine_notes function (you get this when passing NULL) is
23 * combine_notes_concatenate(), which appends the contents of the new note to
24 * the contents of the existing note.
26 typedef int (*combine_notes_fn)(struct object_id *cur_oid,
27 const struct object_id *new_oid);
29 /* Common notes combinators */
30 int combine_notes_concatenate(struct object_id *cur_oid,
31 const struct object_id *new_oid);
32 int combine_notes_overwrite(struct object_id *cur_oid,
33 const struct object_id *new_oid);
34 int combine_notes_ignore(struct object_id *cur_oid,
35 const struct object_id *new_oid);
36 int combine_notes_cat_sort_uniq(struct object_id *cur_oid,
37 const struct object_id *new_oid);
40 * Notes tree object
42 * Encapsulates the internal notes tree structure associated with a notes ref.
43 * Whenever a struct notes_tree pointer is required below, you may pass NULL in
44 * order to use the default/internal notes tree. E.g. you only need to pass a
45 * non-NULL value if you need to refer to several different notes trees
46 * simultaneously.
48 extern struct notes_tree {
49 struct int_node *root;
50 struct non_note *first_non_note, *prev_non_note;
51 char *ref;
52 char *update_ref;
53 combine_notes_fn combine_notes;
54 int initialized;
55 int dirty;
56 } default_notes_tree;
59 * Return the default notes ref.
61 * The default notes ref is the notes ref that is used when notes_ref == NULL
62 * is passed to init_notes().
64 * This the first of the following to be defined:
65 * 1. The '--ref' option to 'git notes', if given
66 * 2. The $GIT_NOTES_REF environment variable, if set
67 * 3. The value of the core.notesRef config variable, if set
68 * 4. GIT_NOTES_DEFAULT_REF (i.e. "refs/notes/commits")
70 const char *default_notes_ref(void);
73 * Flags controlling behaviour of notes tree initialization
75 * Default behaviour is to initialize the notes tree from the tree object
76 * specified by the given (or default) notes ref.
78 #define NOTES_INIT_EMPTY 1
81 * By default, the notes tree is only readable, and the notes ref can be
82 * any treeish. The notes tree can however be made writable with this flag,
83 * in which case only strict ref names can be used.
85 #define NOTES_INIT_WRITABLE 2
88 * Initialize the given notes_tree with the notes tree structure at the given
89 * ref. If given ref is NULL, the value of the $GIT_NOTES_REF environment
90 * variable is used, and if that is missing, the default notes ref is used
91 * ("refs/notes/commits").
93 * If you need to re-initialize a notes_tree structure (e.g. when switching from
94 * one notes ref to another), you must first de-initialize the notes_tree
95 * structure by calling free_notes(struct notes_tree *).
97 * If you pass t == NULL, the default internal notes_tree will be initialized.
99 * The combine_notes function that is passed becomes the default combine_notes
100 * function for the given notes_tree. If NULL is passed, the default
101 * combine_notes function is combine_notes_concatenate().
103 * Precondition: The notes_tree structure is zeroed (this can be achieved with
104 * memset(t, 0, sizeof(struct notes_tree)))
106 void init_notes(struct notes_tree *t, const char *notes_ref,
107 combine_notes_fn combine_notes, int flags);
110 * Add the given note object to the given notes_tree structure
112 * If there already exists a note for the given object_sha1, the given
113 * combine_notes function is invoked to break the tie. If not given (i.e.
114 * combine_notes == NULL), the default combine_notes function for the given
115 * notes_tree is used.
117 * Passing note_sha1 == null_sha1 indicates the addition of an
118 * empty/non-existent note. This is a (potentially expensive) no-op unless
119 * there already exists a note for the given object_sha1, AND combining that
120 * note with the empty note (using the given combine_notes function) results
121 * in a new/changed note.
123 * Returns zero on success; non-zero means combine_notes failed.
125 * IMPORTANT: The changes made by add_note() to the given notes_tree structure
126 * are not persistent until a subsequent call to write_notes_tree() returns
127 * zero.
129 int add_note(struct notes_tree *t, const struct object_id *object_oid,
130 const struct object_id *note_oid, combine_notes_fn combine_notes);
133 * Remove the given note object from the given notes_tree structure
135 * IMPORTANT: The changes made by remove_note() to the given notes_tree
136 * structure are not persistent until a subsequent call to write_notes_tree()
137 * returns zero.
139 * Return 0 if a note was removed; 1 if there was no note to remove.
141 int remove_note(struct notes_tree *t, const unsigned char *object_sha1);
144 * Get the note object SHA1 containing the note data for the given object
146 * Return NULL if the given object has no notes.
148 const struct object_id *get_note(struct notes_tree *t,
149 const struct object_id *object_oid);
152 * Copy a note from one object to another in the given notes_tree.
154 * Returns 1 if the to_obj already has a note and 'force' is false. Otherwise,
155 * returns non-zero if 'force' is true, but the given combine_notes function
156 * failed to combine from_obj's note with to_obj's existing note.
157 * Returns zero on success.
159 * IMPORTANT: The changes made by copy_note() to the given notes_tree structure
160 * are not persistent until a subsequent call to write_notes_tree() returns
161 * zero.
163 int copy_note(struct notes_tree *t,
164 const struct object_id *from_obj, const struct object_id *to_obj,
165 int force, combine_notes_fn combine_notes);
168 * Flags controlling behaviour of for_each_note()
170 * Default behaviour of for_each_note() is to traverse every single note object
171 * in the given notes tree, unpacking subtree entries along the way.
172 * The following flags can be used to alter the default behaviour:
174 * - DONT_UNPACK_SUBTREES causes for_each_note() NOT to unpack and recurse into
175 * subtree entries while traversing the notes tree. This causes notes within
176 * those subtrees NOT to be passed to the callback. Use this flag if you
177 * don't want to traverse _all_ notes, but only want to traverse the parts
178 * of the notes tree that have already been unpacked (this includes at least
179 * all notes that have been added/changed).
181 * - YIELD_SUBTREES causes any subtree entries that are encountered to be
182 * passed to the callback, before recursing into them. Subtree entries are
183 * not note objects, but represent intermediate directories in the notes
184 * tree. When passed to the callback, subtree entries will have a trailing
185 * slash in their path, which the callback may use to differentiate between
186 * note entries and subtree entries. Note that already-unpacked subtree
187 * entries are not part of the notes tree, and will therefore not be yielded.
188 * If this flag is used together with DONT_UNPACK_SUBTREES, for_each_note()
189 * will yield the subtree entry, but not recurse into it.
191 #define FOR_EACH_NOTE_DONT_UNPACK_SUBTREES 1
192 #define FOR_EACH_NOTE_YIELD_SUBTREES 2
195 * Invoke the specified callback function for each note in the given notes_tree
197 * If the callback returns nonzero, the note walk is aborted, and the return
198 * value from the callback is returned from for_each_note(). Hence, a zero
199 * return value from for_each_note() indicates that all notes were walked
200 * successfully.
202 * IMPORTANT: The callback function is NOT allowed to change the notes tree.
203 * In other words, the following functions can NOT be invoked (on the current
204 * notes tree) from within the callback:
205 * - add_note()
206 * - remove_note()
207 * - copy_note()
208 * - free_notes()
210 typedef int each_note_fn(const struct object_id *object_oid,
211 const struct object_id *note_oid, char *note_path,
212 void *cb_data);
213 int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
214 void *cb_data);
217 * Write the given notes_tree structure to the object database
219 * Creates a new tree object encapsulating the current state of the given
220 * notes_tree, and stores its object id into the 'result' argument.
222 * Returns zero on success, non-zero on failure.
224 * IMPORTANT: Changes made to the given notes_tree are not persistent until
225 * this function has returned zero. Please also remember to create a
226 * corresponding commit object, and update the appropriate notes ref.
228 int write_notes_tree(struct notes_tree *t, struct object_id *result);
230 /* Flags controlling the operation of prune */
231 #define NOTES_PRUNE_VERBOSE 1
232 #define NOTES_PRUNE_DRYRUN 2
234 * Remove all notes annotating non-existing objects from the given notes tree
236 * All notes in the given notes_tree that are associated with objects that no
237 * longer exist in the database, are removed from the notes tree.
239 * IMPORTANT: The changes made by prune_notes() to the given notes_tree
240 * structure are not persistent until a subsequent call to write_notes_tree()
241 * returns zero.
243 void prune_notes(struct notes_tree *t, int flags);
246 * Free (and de-initialize) the given notes_tree structure
248 * IMPORTANT: Changes made to the given notes_tree since the last, successful
249 * call to write_notes_tree() will be lost.
251 void free_notes(struct notes_tree *t);
253 struct string_list;
255 struct display_notes_opt {
256 int use_default_notes;
257 struct string_list extra_notes_refs;
261 * Load the notes machinery for displaying several notes trees.
263 * If 'opt' is not NULL, then it specifies additional settings for the
264 * displaying:
266 * - suppress_default_notes indicates that the notes from
267 * core.notesRef and notes.displayRef should not be loaded.
269 * - extra_notes_refs may contain a list of globs (in the same style
270 * as notes.displayRef) where notes should be loaded from.
272 void init_display_notes(struct display_notes_opt *opt);
275 * Append notes for the given 'object_sha1' from all trees set up by
276 * init_display_notes() to 'sb'. The 'flags' are a bitwise
277 * combination of
279 * - NOTES_SHOW_HEADER: add a 'Notes (refname):' header
281 * - NOTES_INDENT: indent the notes by 4 places
283 * You *must* call init_display_notes() before using this function.
285 void format_display_notes(const struct object_id *object_oid,
286 struct strbuf *sb, const char *output_encoding, int raw);
289 * Load the notes tree from each ref listed in 'refs'. The output is
290 * an array of notes_tree*, terminated by a NULL.
292 struct notes_tree **load_notes_trees(struct string_list *refs, int flags);
295 * Add all refs that match 'glob' to the 'list'.
297 void string_list_add_refs_by_glob(struct string_list *list, const char *glob);
300 * Add all refs from a colon-separated glob list 'globs' to the end of
301 * 'list'. Empty components are ignored. This helper is used to
302 * parse GIT_NOTES_DISPLAY_REF style environment variables.
304 void string_list_add_refs_from_colon_sep(struct string_list *list,
305 const char *globs);
307 /* Expand inplace a note ref like "foo" or "notes/foo" into "refs/notes/foo" */
308 void expand_notes_ref(struct strbuf *sb);
311 * Similar to expand_notes_ref, but will check whether the ref can be located
312 * via get_sha1 first, and only falls back to expand_notes_ref in the case
313 * where get_sha1 fails.
315 void expand_loose_notes_ref(struct strbuf *sb);
317 #endif