(trivial) notes.h: Minor documentation fixes to copy_notes()
[git/git.git] / notes.h
CommitLineData
a97a7468
JS
1#ifndef NOTES_H
2#define NOTES_H
3
73f464b5
JH
4/*
5 * Function type for combining two notes annotating the same object.
6 *
7 * When adding a new note annotating the same object as an existing note, it is
8 * up to the caller to decide how to combine the two notes. The decision is
9 * made by passing in a function of the following form. The function accepts
10 * two SHA1s -- of the existing note and the new note, respectively. The
11 * function then combines the notes in whatever way it sees fit, and writes the
12 * resulting SHA1 into the first SHA1 argument (cur_sha1). A non-zero return
13 * value indicates failure.
14 *
15 * The two given SHA1s must both be non-NULL and different from each other.
16 *
17 * The default combine_notes function (you get this when passing NULL) is
18 * combine_notes_concatenate(), which appends the contents of the new note to
19 * the contents of the existing note.
20 */
4e0d7a80 21typedef int (*combine_notes_fn)(unsigned char *cur_sha1, const unsigned char *new_sha1);
73f464b5
JH
22
23/* Common notes combinators */
24int combine_notes_concatenate(unsigned char *cur_sha1, const unsigned char *new_sha1);
25int combine_notes_overwrite(unsigned char *cur_sha1, const unsigned char *new_sha1);
26int combine_notes_ignore(unsigned char *cur_sha1, const unsigned char *new_sha1);
27
cd305392
JH
28/*
29 * Notes tree object
30 *
31 * Encapsulates the internal notes tree structure associated with a notes ref.
32 * Whenever a struct notes_tree pointer is required below, you may pass NULL in
33 * order to use the default/internal notes tree. E.g. you only need to pass a
34 * non-NULL value if you need to refer to several different notes trees
35 * simultaneously.
36 */
37extern struct notes_tree {
38 struct int_node *root;
851c2b37 39 struct non_note *first_non_note, *prev_non_note;
cd305392 40 char *ref;
4e0d7a80 41 combine_notes_fn combine_notes;
cd305392 42 int initialized;
7f710ea9 43 int dirty;
cd305392
JH
44} default_notes_tree;
45
709f79b0
JH
46/*
47 * Flags controlling behaviour of notes tree initialization
48 *
49 * Default behaviour is to initialize the notes tree from the tree object
50 * specified by the given (or default) notes ref.
51 */
52#define NOTES_INIT_EMPTY 1
53
54/*
cd305392 55 * Initialize the given notes_tree with the notes tree structure at the given
709f79b0
JH
56 * ref. If given ref is NULL, the value of the $GIT_NOTES_REF environment
57 * variable is used, and if that is missing, the default notes ref is used
58 * ("refs/notes/commits").
59 *
cd305392
JH
60 * If you need to re-intialize a notes_tree structure (e.g. when switching from
61 * one notes ref to another), you must first de-initialize the notes_tree
62 * structure by calling free_notes(struct notes_tree *).
63 *
64 * If you pass t == NULL, the default internal notes_tree will be initialized.
65 *
73f464b5
JH
66 * The combine_notes function that is passed becomes the default combine_notes
67 * function for the given notes_tree. If NULL is passed, the default
68 * combine_notes function is combine_notes_concatenate().
69 *
cd305392
JH
70 * Precondition: The notes_tree structure is zeroed (this can be achieved with
71 * memset(t, 0, sizeof(struct notes_tree)))
709f79b0 72 */
73f464b5
JH
73void init_notes(struct notes_tree *t, const char *notes_ref,
74 combine_notes_fn combine_notes, int flags);
709f79b0 75
61a7cca0 76/*
cd305392 77 * Add the given note object to the given notes_tree structure
61a7cca0 78 *
cd305392 79 * IMPORTANT: The changes made by add_note() to the given notes_tree structure
61a7cca0
JH
80 * are not persistent until a subsequent call to write_notes_tree() returns
81 * zero.
82 */
cd305392 83void add_note(struct notes_tree *t, const unsigned char *object_sha1,
73f464b5 84 const unsigned char *note_sha1, combine_notes_fn combine_notes);
2626b536 85
61a7cca0 86/*
cd305392 87 * Remove the given note object from the given notes_tree structure
61a7cca0 88 *
cd305392 89 * IMPORTANT: The changes made by remove_note() to the given notes_tree
61a7cca0
JH
90 * structure are not persistent until a subsequent call to write_notes_tree()
91 * returns zero.
92 */
cd305392 93void remove_note(struct notes_tree *t, const unsigned char *object_sha1);
1ec666b0 94
9b391f21
JH
95/*
96 * Get the note object SHA1 containing the note data for the given object
97 *
98 * Return NULL if the given object has no notes.
99 */
cd305392
JH
100const unsigned char *get_note(struct notes_tree *t,
101 const unsigned char *object_sha1);
9b391f21 102
160baa0d
TR
103/*
104 * Copy a note from one object to another in the given notes_tree.
105 *
106 * Fails if the to_obj already has a note unless 'force' is true.
55d06077
JH
107 *
108 * IMPORTANT: The changes made by copy_note() to the given notes_tree structure
109 * are not persistent until a subsequent call to write_notes_tree() returns
110 * zero.
160baa0d
TR
111 */
112int copy_note(struct notes_tree *t,
113 const unsigned char *from_obj, const unsigned char *to_obj,
114 int force, combine_notes_fn combine_fn);
115
73f77b90
JH
116/*
117 * Flags controlling behaviour of for_each_note()
118 *
119 * Default behaviour of for_each_note() is to traverse every single note object
cd305392 120 * in the given notes tree, unpacking subtree entries along the way.
73f77b90
JH
121 * The following flags can be used to alter the default behaviour:
122 *
123 * - DONT_UNPACK_SUBTREES causes for_each_note() NOT to unpack and recurse into
124 * subtree entries while traversing the notes tree. This causes notes within
125 * those subtrees NOT to be passed to the callback. Use this flag if you
126 * don't want to traverse _all_ notes, but only want to traverse the parts
127 * of the notes tree that have already been unpacked (this includes at least
128 * all notes that have been added/changed).
129 *
130 * - YIELD_SUBTREES causes any subtree entries that are encountered to be
131 * passed to the callback, before recursing into them. Subtree entries are
132 * not note objects, but represent intermediate directories in the notes
133 * tree. When passed to the callback, subtree entries will have a trailing
134 * slash in their path, which the callback may use to differentiate between
135 * note entries and subtree entries. Note that already-unpacked subtree
136 * entries are not part of the notes tree, and will therefore not be yielded.
137 * If this flag is used together with DONT_UNPACK_SUBTREES, for_each_note()
138 * will yield the subtree entry, but not recurse into it.
139 */
140#define FOR_EACH_NOTE_DONT_UNPACK_SUBTREES 1
141#define FOR_EACH_NOTE_YIELD_SUBTREES 2
142
143/*
cd305392 144 * Invoke the specified callback function for each note in the given notes_tree
73f77b90
JH
145 *
146 * If the callback returns nonzero, the note walk is aborted, and the return
147 * value from the callback is returned from for_each_note(). Hence, a zero
148 * return value from for_each_note() indicates that all notes were walked
149 * successfully.
150 *
151 * IMPORTANT: The callback function is NOT allowed to change the notes tree.
152 * In other words, the following functions can NOT be invoked (on the current
153 * notes tree) from within the callback:
154 * - add_note()
155 * - remove_note()
55d06077 156 * - copy_note()
73f77b90
JH
157 * - free_notes()
158 */
159typedef int each_note_fn(const unsigned char *object_sha1,
160 const unsigned char *note_sha1, char *note_path,
161 void *cb_data);
cd305392
JH
162int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
163 void *cb_data);
73f77b90 164
61a7cca0 165/*
cd305392 166 * Write the given notes_tree structure to the object database
61a7cca0 167 *
cd305392
JH
168 * Creates a new tree object encapsulating the current state of the given
169 * notes_tree, and stores its SHA1 into the 'result' argument.
61a7cca0
JH
170 *
171 * Returns zero on success, non-zero on failure.
172 *
cd305392
JH
173 * IMPORTANT: Changes made to the given notes_tree are not persistent until
174 * this function has returned zero. Please also remember to create a
175 * corresponding commit object, and update the appropriate notes ref.
61a7cca0 176 */
cd305392 177int write_notes_tree(struct notes_tree *t, unsigned char *result);
61a7cca0 178
a9f2adff
MG
179/* Flags controlling the operation of prune */
180#define NOTES_PRUNE_VERBOSE 1
181#define NOTES_PRUNE_DRYRUN 2
00fbe636
JH
182/*
183 * Remove all notes annotating non-existing objects from the given notes tree
184 *
185 * All notes in the given notes_tree that are associated with objects that no
186 * longer exist in the database, are removed from the notes tree.
187 *
188 * IMPORTANT: The changes made by prune_notes() to the given notes_tree
189 * structure are not persistent until a subsequent call to write_notes_tree()
190 * returns zero.
191 */
a9f2adff 192void prune_notes(struct notes_tree *t, int flags);
00fbe636 193
61a7cca0 194/*
cd305392 195 * Free (and de-initialize) the given notes_tree structure
61a7cca0 196 *
cd305392 197 * IMPORTANT: Changes made to the given notes_tree since the last, successful
61a7cca0
JH
198 * call to write_notes_tree() will be lost.
199 */
cd305392 200void free_notes(struct notes_tree *t);
27d57564 201
a7e7eff6 202/* Flags controlling how notes are formatted */
c56fcc89
JH
203#define NOTES_SHOW_HEADER 1
204#define NOTES_INDENT 2
205
a7e7eff6
JH
206/*
207 * Fill the given strbuf with the notes associated with the given object.
208 *
cd305392 209 * If the given notes_tree structure is not initialized, it will be auto-
a7e7eff6 210 * initialized to the default value (see documentation for init_notes() above).
cd305392
JH
211 * If the given notes_tree is NULL, the internal/default notes_tree will be
212 * used instead.
a7e7eff6
JH
213 *
214 * 'flags' is a bitwise combination of the above formatting flags.
215 */
cd305392
JH
216void format_note(struct notes_tree *t, const unsigned char *object_sha1,
217 struct strbuf *sb, const char *output_encoding, int flags);
a97a7468 218
894a9d33
TR
219
220struct string_list;
221
222struct display_notes_opt {
a751b5cc 223 unsigned int suppress_default_notes:1;
894a9d33
TR
224 struct string_list *extra_notes_refs;
225};
226
227/*
228 * Load the notes machinery for displaying several notes trees.
229 *
230 * If 'opt' is not NULL, then it specifies additional settings for the
231 * displaying:
232 *
233 * - suppress_default_notes indicates that the notes from
234 * core.notesRef and notes.displayRef should not be loaded.
235 *
236 * - extra_notes_refs may contain a list of globs (in the same style
237 * as notes.displayRef) where notes should be loaded from.
238 */
239void init_display_notes(struct display_notes_opt *opt);
240
241/*
242 * Append notes for the given 'object_sha1' from all trees set up by
243 * init_display_notes() to 'sb'. The 'flags' are a bitwise
244 * combination of
245 *
246 * - NOTES_SHOW_HEADER: add a 'Notes (refname):' header
247 *
248 * - NOTES_INDENT: indent the notes by 4 places
249 *
250 * You *must* call init_display_notes() before using this function.
251 */
252void format_display_notes(const unsigned char *object_sha1,
253 struct strbuf *sb, const char *output_encoding, int flags);
254
255/*
256 * Load the notes tree from each ref listed in 'refs'. The output is
257 * an array of notes_tree*, terminated by a NULL.
258 */
259struct notes_tree **load_notes_trees(struct string_list *refs);
260
261/*
262 * Add all refs that match 'glob' to the 'list'.
263 */
264void string_list_add_refs_by_glob(struct string_list *list, const char *glob);
265
266/*
267 * Add all refs from a colon-separated glob list 'globs' to the end of
268 * 'list'. Empty components are ignored. This helper is used to
269 * parse GIT_NOTES_DISPLAY_REF style environment variables.
270 */
271void string_list_add_refs_from_colon_sep(struct string_list *list,
272 const char *globs);
273
a97a7468 274#endif