sync with girocco/v2.11.4+
[git/gitweb.git] / notes.h
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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 SHA1s -- 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 SHA1 into the first SHA1 argument (cur_sha1). A non-zero return
15 * value indicates failure.
17 * The two given SHA1s shall both be non-NULL and different from each other.
18 * Either of them (but not both) may be == null_sha1, which indicates an
19 * empty/non-existent note. If the resulting SHA1 (cur_sha1) is == null_sha1,
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)(unsigned char *cur_sha1, const unsigned char *new_sha1);
28 /* Common notes combinators */
29 int combine_notes_concatenate(unsigned char *cur_sha1, const unsigned char *new_sha1);
30 int combine_notes_overwrite(unsigned char *cur_sha1, const unsigned char *new_sha1);
31 int combine_notes_ignore(unsigned char *cur_sha1, const unsigned char *new_sha1);
32 int combine_notes_cat_sort_uniq(unsigned char *cur_sha1, const unsigned char *new_sha1);
35 * Notes tree object
37 * Encapsulates the internal notes tree structure associated with a notes ref.
38 * Whenever a struct notes_tree pointer is required below, you may pass NULL in
39 * order to use the default/internal notes tree. E.g. you only need to pass a
40 * non-NULL value if you need to refer to several different notes trees
41 * simultaneously.
43 extern struct notes_tree {
44 struct int_node *root;
45 struct non_note *first_non_note, *prev_non_note;
46 char *ref;
47 char *update_ref;
48 combine_notes_fn combine_notes;
49 int initialized;
50 int dirty;
51 } default_notes_tree;
54 * Return the default notes ref.
56 * The default notes ref is the notes ref that is used when notes_ref == NULL
57 * is passed to init_notes().
59 * This the first of the following to be defined:
60 * 1. The '--ref' option to 'git notes', if given
61 * 2. The $GIT_NOTES_REF environment variable, if set
62 * 3. The value of the core.notesRef config variable, if set
63 * 4. GIT_NOTES_DEFAULT_REF (i.e. "refs/notes/commits")
65 const char *default_notes_ref(void);
68 * Flags controlling behaviour of notes tree initialization
70 * Default behaviour is to initialize the notes tree from the tree object
71 * specified by the given (or default) notes ref.
73 #define NOTES_INIT_EMPTY 1
76 * By default, the notes tree is only readable, and the notes ref can be
77 * any treeish. The notes tree can however be made writable with this flag,
78 * in which case only strict ref names can be used.
80 #define NOTES_INIT_WRITABLE 2
83 * Initialize the given notes_tree with the notes tree structure at the given
84 * ref. If given ref is NULL, the value of the $GIT_NOTES_REF environment
85 * variable is used, and if that is missing, the default notes ref is used
86 * ("refs/notes/commits").
88 * If you need to re-initialize a notes_tree structure (e.g. when switching from
89 * one notes ref to another), you must first de-initialize the notes_tree
90 * structure by calling free_notes(struct notes_tree *).
92 * If you pass t == NULL, the default internal notes_tree will be initialized.
94 * The combine_notes function that is passed becomes the default combine_notes
95 * function for the given notes_tree. If NULL is passed, the default
96 * combine_notes function is combine_notes_concatenate().
98 * Precondition: The notes_tree structure is zeroed (this can be achieved with
99 * memset(t, 0, sizeof(struct notes_tree)))
101 void init_notes(struct notes_tree *t, const char *notes_ref,
102 combine_notes_fn combine_notes, int flags);
105 * Add the given note object to the given notes_tree structure
107 * If there already exists a note for the given object_sha1, the given
108 * combine_notes function is invoked to break the tie. If not given (i.e.
109 * combine_notes == NULL), the default combine_notes function for the given
110 * notes_tree is used.
112 * Passing note_sha1 == null_sha1 indicates the addition of an
113 * empty/non-existent note. This is a (potentially expensive) no-op unless
114 * there already exists a note for the given object_sha1, AND combining that
115 * note with the empty note (using the given combine_notes function) results
116 * in a new/changed note.
118 * Returns zero on success; non-zero means combine_notes failed.
120 * IMPORTANT: The changes made by add_note() to the given notes_tree structure
121 * are not persistent until a subsequent call to write_notes_tree() returns
122 * zero.
124 int add_note(struct notes_tree *t, const unsigned char *object_sha1,
125 const unsigned char *note_sha1, combine_notes_fn combine_notes);
128 * Remove the given note object from the given notes_tree structure
130 * IMPORTANT: The changes made by remove_note() to the given notes_tree
131 * structure are not persistent until a subsequent call to write_notes_tree()
132 * returns zero.
134 * Return 0 if a note was removed; 1 if there was no note to remove.
136 int remove_note(struct notes_tree *t, const unsigned char *object_sha1);
139 * Get the note object SHA1 containing the note data for the given object
141 * Return NULL if the given object has no notes.
143 const unsigned char *get_note(struct notes_tree *t,
144 const unsigned char *object_sha1);
147 * Copy a note from one object to another in the given notes_tree.
149 * Returns 1 if the to_obj already has a note and 'force' is false. Otherwise,
150 * returns non-zero if 'force' is true, but the given combine_notes function
151 * failed to combine from_obj's note with to_obj's existing note.
152 * Returns zero on success.
154 * IMPORTANT: The changes made by copy_note() to the given notes_tree structure
155 * are not persistent until a subsequent call to write_notes_tree() returns
156 * zero.
158 int copy_note(struct notes_tree *t,
159 const unsigned char *from_obj, const unsigned char *to_obj,
160 int force, combine_notes_fn combine_notes);
163 * Flags controlling behaviour of for_each_note()
165 * Default behaviour of for_each_note() is to traverse every single note object
166 * in the given notes tree, unpacking subtree entries along the way.
167 * The following flags can be used to alter the default behaviour:
169 * - DONT_UNPACK_SUBTREES causes for_each_note() NOT to unpack and recurse into
170 * subtree entries while traversing the notes tree. This causes notes within
171 * those subtrees NOT to be passed to the callback. Use this flag if you
172 * don't want to traverse _all_ notes, but only want to traverse the parts
173 * of the notes tree that have already been unpacked (this includes at least
174 * all notes that have been added/changed).
176 * - YIELD_SUBTREES causes any subtree entries that are encountered to be
177 * passed to the callback, before recursing into them. Subtree entries are
178 * not note objects, but represent intermediate directories in the notes
179 * tree. When passed to the callback, subtree entries will have a trailing
180 * slash in their path, which the callback may use to differentiate between
181 * note entries and subtree entries. Note that already-unpacked subtree
182 * entries are not part of the notes tree, and will therefore not be yielded.
183 * If this flag is used together with DONT_UNPACK_SUBTREES, for_each_note()
184 * will yield the subtree entry, but not recurse into it.
186 #define FOR_EACH_NOTE_DONT_UNPACK_SUBTREES 1
187 #define FOR_EACH_NOTE_YIELD_SUBTREES 2
190 * Invoke the specified callback function for each note in the given notes_tree
192 * If the callback returns nonzero, the note walk is aborted, and the return
193 * value from the callback is returned from for_each_note(). Hence, a zero
194 * return value from for_each_note() indicates that all notes were walked
195 * successfully.
197 * IMPORTANT: The callback function is NOT allowed to change the notes tree.
198 * In other words, the following functions can NOT be invoked (on the current
199 * notes tree) from within the callback:
200 * - add_note()
201 * - remove_note()
202 * - copy_note()
203 * - free_notes()
205 typedef int each_note_fn(const unsigned char *object_sha1,
206 const unsigned char *note_sha1, char *note_path,
207 void *cb_data);
208 int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
209 void *cb_data);
212 * Write the given notes_tree structure to the object database
214 * Creates a new tree object encapsulating the current state of the given
215 * notes_tree, and stores its SHA1 into the 'result' argument.
217 * Returns zero on success, non-zero on failure.
219 * IMPORTANT: Changes made to the given notes_tree are not persistent until
220 * this function has returned zero. Please also remember to create a
221 * corresponding commit object, and update the appropriate notes ref.
223 int write_notes_tree(struct notes_tree *t, unsigned char *result);
225 /* Flags controlling the operation of prune */
226 #define NOTES_PRUNE_VERBOSE 1
227 #define NOTES_PRUNE_DRYRUN 2
229 * Remove all notes annotating non-existing objects from the given notes tree
231 * All notes in the given notes_tree that are associated with objects that no
232 * longer exist in the database, are removed from the notes tree.
234 * IMPORTANT: The changes made by prune_notes() to the given notes_tree
235 * structure are not persistent until a subsequent call to write_notes_tree()
236 * returns zero.
238 void prune_notes(struct notes_tree *t, int flags);
241 * Free (and de-initialize) the given notes_tree structure
243 * IMPORTANT: Changes made to the given notes_tree since the last, successful
244 * call to write_notes_tree() will be lost.
246 void free_notes(struct notes_tree *t);
248 struct string_list;
250 struct display_notes_opt {
251 int use_default_notes;
252 struct string_list extra_notes_refs;
256 * Load the notes machinery for displaying several notes trees.
258 * If 'opt' is not NULL, then it specifies additional settings for the
259 * displaying:
261 * - suppress_default_notes indicates that the notes from
262 * core.notesRef and notes.displayRef should not be loaded.
264 * - extra_notes_refs may contain a list of globs (in the same style
265 * as notes.displayRef) where notes should be loaded from.
267 void init_display_notes(struct display_notes_opt *opt);
270 * Append notes for the given 'object_sha1' from all trees set up by
271 * init_display_notes() to 'sb'. The 'flags' are a bitwise
272 * combination of
274 * - NOTES_SHOW_HEADER: add a 'Notes (refname):' header
276 * - NOTES_INDENT: indent the notes by 4 places
278 * You *must* call init_display_notes() before using this function.
280 void format_display_notes(const unsigned char *object_sha1,
281 struct strbuf *sb, const char *output_encoding, int raw);
284 * Load the notes tree from each ref listed in 'refs'. The output is
285 * an array of notes_tree*, terminated by a NULL.
287 struct notes_tree **load_notes_trees(struct string_list *refs, int flags);
290 * Add all refs that match 'glob' to the 'list'.
292 void string_list_add_refs_by_glob(struct string_list *list, const char *glob);
295 * Add all refs from a colon-separated glob list 'globs' to the end of
296 * 'list'. Empty components are ignored. This helper is used to
297 * parse GIT_NOTES_DISPLAY_REF style environment variables.
299 void string_list_add_refs_from_colon_sep(struct string_list *list,
300 const char *globs);
302 /* Expand inplace a note ref like "foo" or "notes/foo" into "refs/notes/foo" */
303 void expand_notes_ref(struct strbuf *sb);
306 * Similar to expand_notes_ref, but will check whether the ref can be located
307 * via get_sha1 first, and only falls back to expand_notes_ref in the case
308 * where get_sha1 fails.
310 void expand_loose_notes_ref(struct strbuf *sb);
312 #endif