git/notes.h
Junio C Hamano 96531a5ede notes.c: mark a private file-scope symbol as static
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-15 22:58:20 -07:00

302 lines
11 KiB
C

#ifndef NOTES_H
#define NOTES_H
#include "string-list.h"
/*
* Function type for combining two notes annotating the same object.
*
* When adding a new note annotating the same object as an existing note, it is
* up to the caller to decide how to combine the two notes. The decision is
* made by passing in a function of the following form. The function accepts
* two SHA1s -- of the existing note and the new note, respectively. The
* function then combines the notes in whatever way it sees fit, and writes the
* resulting SHA1 into the first SHA1 argument (cur_sha1). A non-zero return
* value indicates failure.
*
* The two given SHA1s shall both be non-NULL and different from each other.
* Either of them (but not both) may be == null_sha1, which indicates an
* empty/non-existent note. If the resulting SHA1 (cur_sha1) is == null_sha1,
* the note will be removed from the notes tree.
*
* The default combine_notes function (you get this when passing NULL) is
* combine_notes_concatenate(), which appends the contents of the new note to
* the contents of the existing note.
*/
typedef int (*combine_notes_fn)(unsigned char *cur_sha1, const unsigned char *new_sha1);
/* Common notes combinators */
int combine_notes_concatenate(unsigned char *cur_sha1, const unsigned char *new_sha1);
int combine_notes_overwrite(unsigned char *cur_sha1, const unsigned char *new_sha1);
int combine_notes_ignore(unsigned char *cur_sha1, const unsigned char *new_sha1);
int combine_notes_cat_sort_uniq(unsigned char *cur_sha1, const unsigned char *new_sha1);
/*
* Notes tree object
*
* Encapsulates the internal notes tree structure associated with a notes ref.
* Whenever a struct notes_tree pointer is required below, you may pass NULL in
* order to use the default/internal notes tree. E.g. you only need to pass a
* non-NULL value if you need to refer to several different notes trees
* simultaneously.
*/
extern struct notes_tree {
struct int_node *root;
struct non_note *first_non_note, *prev_non_note;
char *ref;
combine_notes_fn combine_notes;
int initialized;
int dirty;
} default_notes_tree;
/*
* Return the default notes ref.
*
* The default notes ref is the notes ref that is used when notes_ref == NULL
* is passed to init_notes().
*
* This the first of the following to be defined:
* 1. The '--ref' option to 'git notes', if given
* 2. The $GIT_NOTES_REF environment variable, if set
* 3. The value of the core.notesRef config variable, if set
* 4. GIT_NOTES_DEFAULT_REF (i.e. "refs/notes/commits")
*/
const char *default_notes_ref(void);
/*
* Flags controlling behaviour of notes tree initialization
*
* Default behaviour is to initialize the notes tree from the tree object
* specified by the given (or default) notes ref.
*/
#define NOTES_INIT_EMPTY 1
/*
* Initialize the given notes_tree with the notes tree structure at the given
* ref. If given ref is NULL, the value of the $GIT_NOTES_REF environment
* variable is used, and if that is missing, the default notes ref is used
* ("refs/notes/commits").
*
* If you need to re-intialize a notes_tree structure (e.g. when switching from
* one notes ref to another), you must first de-initialize the notes_tree
* structure by calling free_notes(struct notes_tree *).
*
* If you pass t == NULL, the default internal notes_tree will be initialized.
*
* The combine_notes function that is passed becomes the default combine_notes
* function for the given notes_tree. If NULL is passed, the default
* combine_notes function is combine_notes_concatenate().
*
* Precondition: The notes_tree structure is zeroed (this can be achieved with
* memset(t, 0, sizeof(struct notes_tree)))
*/
void init_notes(struct notes_tree *t, const char *notes_ref,
combine_notes_fn combine_notes, int flags);
/*
* Add the given note object to the given notes_tree structure
*
* If there already exists a note for the given object_sha1, the given
* combine_notes function is invoked to break the tie. If not given (i.e.
* combine_notes == NULL), the default combine_notes function for the given
* notes_tree is used.
*
* Passing note_sha1 == null_sha1 indicates the addition of an
* empty/non-existent note. This is a (potentially expensive) no-op unless
* there already exists a note for the given object_sha1, AND combining that
* note with the empty note (using the given combine_notes function) results
* in a new/changed note.
*
* Returns zero on success; non-zero means combine_notes failed.
*
* IMPORTANT: The changes made by add_note() to the given notes_tree structure
* are not persistent until a subsequent call to write_notes_tree() returns
* zero.
*/
int add_note(struct notes_tree *t, const unsigned char *object_sha1,
const unsigned char *note_sha1, combine_notes_fn combine_notes);
/*
* Remove the given note object from the given notes_tree structure
*
* IMPORTANT: The changes made by remove_note() to the given notes_tree
* structure are not persistent until a subsequent call to write_notes_tree()
* returns zero.
*
* Return 0 if a note was removed; 1 if there was no note to remove.
*/
int remove_note(struct notes_tree *t, const unsigned char *object_sha1);
/*
* Get the note object SHA1 containing the note data for the given object
*
* Return NULL if the given object has no notes.
*/
const unsigned char *get_note(struct notes_tree *t,
const unsigned char *object_sha1);
/*
* Copy a note from one object to another in the given notes_tree.
*
* Returns 1 if the to_obj already has a note and 'force' is false. Otherwise,
* returns non-zero if 'force' is true, but the given combine_notes function
* failed to combine from_obj's note with to_obj's existing note.
* Returns zero on success.
*
* IMPORTANT: The changes made by copy_note() to the given notes_tree structure
* are not persistent until a subsequent call to write_notes_tree() returns
* zero.
*/
int copy_note(struct notes_tree *t,
const unsigned char *from_obj, const unsigned char *to_obj,
int force, combine_notes_fn combine_notes);
/*
* Flags controlling behaviour of for_each_note()
*
* Default behaviour of for_each_note() is to traverse every single note object
* in the given notes tree, unpacking subtree entries along the way.
* The following flags can be used to alter the default behaviour:
*
* - DONT_UNPACK_SUBTREES causes for_each_note() NOT to unpack and recurse into
* subtree entries while traversing the notes tree. This causes notes within
* those subtrees NOT to be passed to the callback. Use this flag if you
* don't want to traverse _all_ notes, but only want to traverse the parts
* of the notes tree that have already been unpacked (this includes at least
* all notes that have been added/changed).
*
* - YIELD_SUBTREES causes any subtree entries that are encountered to be
* passed to the callback, before recursing into them. Subtree entries are
* not note objects, but represent intermediate directories in the notes
* tree. When passed to the callback, subtree entries will have a trailing
* slash in their path, which the callback may use to differentiate between
* note entries and subtree entries. Note that already-unpacked subtree
* entries are not part of the notes tree, and will therefore not be yielded.
* If this flag is used together with DONT_UNPACK_SUBTREES, for_each_note()
* will yield the subtree entry, but not recurse into it.
*/
#define FOR_EACH_NOTE_DONT_UNPACK_SUBTREES 1
#define FOR_EACH_NOTE_YIELD_SUBTREES 2
/*
* Invoke the specified callback function for each note in the given notes_tree
*
* If the callback returns nonzero, the note walk is aborted, and the return
* value from the callback is returned from for_each_note(). Hence, a zero
* return value from for_each_note() indicates that all notes were walked
* successfully.
*
* IMPORTANT: The callback function is NOT allowed to change the notes tree.
* In other words, the following functions can NOT be invoked (on the current
* notes tree) from within the callback:
* - add_note()
* - remove_note()
* - copy_note()
* - free_notes()
*/
typedef int each_note_fn(const unsigned char *object_sha1,
const unsigned char *note_sha1, char *note_path,
void *cb_data);
int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
void *cb_data);
/*
* Write the given notes_tree structure to the object database
*
* Creates a new tree object encapsulating the current state of the given
* notes_tree, and stores its SHA1 into the 'result' argument.
*
* Returns zero on success, non-zero on failure.
*
* IMPORTANT: Changes made to the given notes_tree are not persistent until
* this function has returned zero. Please also remember to create a
* corresponding commit object, and update the appropriate notes ref.
*/
int write_notes_tree(struct notes_tree *t, unsigned char *result);
/* Flags controlling the operation of prune */
#define NOTES_PRUNE_VERBOSE 1
#define NOTES_PRUNE_DRYRUN 2
/*
* Remove all notes annotating non-existing objects from the given notes tree
*
* All notes in the given notes_tree that are associated with objects that no
* longer exist in the database, are removed from the notes tree.
*
* IMPORTANT: The changes made by prune_notes() to the given notes_tree
* structure are not persistent until a subsequent call to write_notes_tree()
* returns zero.
*/
void prune_notes(struct notes_tree *t, int flags);
/*
* Free (and de-initialize) the given notes_tree structure
*
* IMPORTANT: Changes made to the given notes_tree since the last, successful
* call to write_notes_tree() will be lost.
*/
void free_notes(struct notes_tree *t);
/* Flags controlling how notes are formatted */
#define NOTES_SHOW_HEADER 1
#define NOTES_INDENT 2
struct string_list;
struct display_notes_opt {
int use_default_notes;
struct string_list extra_notes_refs;
};
/*
* Load the notes machinery for displaying several notes trees.
*
* If 'opt' is not NULL, then it specifies additional settings for the
* displaying:
*
* - suppress_default_notes indicates that the notes from
* core.notesRef and notes.displayRef should not be loaded.
*
* - extra_notes_refs may contain a list of globs (in the same style
* as notes.displayRef) where notes should be loaded from.
*/
void init_display_notes(struct display_notes_opt *opt);
/*
* Append notes for the given 'object_sha1' from all trees set up by
* init_display_notes() to 'sb'. The 'flags' are a bitwise
* combination of
*
* - NOTES_SHOW_HEADER: add a 'Notes (refname):' header
*
* - NOTES_INDENT: indent the notes by 4 places
*
* You *must* call init_display_notes() before using this function.
*/
void format_display_notes(const unsigned char *object_sha1,
struct strbuf *sb, const char *output_encoding, int flags);
/*
* Load the notes tree from each ref listed in 'refs'. The output is
* an array of notes_tree*, terminated by a NULL.
*/
struct notes_tree **load_notes_trees(struct string_list *refs);
/*
* Add all refs that match 'glob' to the 'list'.
*/
void string_list_add_refs_by_glob(struct string_list *list, const char *glob);
/*
* Add all refs from a colon-separated glob list 'globs' to the end of
* 'list'. Empty components are ignored. This helper is used to
* parse GIT_NOTES_DISPLAY_REF style environment variables.
*/
void string_list_add_refs_from_colon_sep(struct string_list *list,
const char *globs);
/* Expand inplace a note ref like "foo" or "notes/foo" into "refs/notes/foo" */
void expand_notes_ref(struct strbuf *sb);
#endif