diff options
Diffstat (limited to 'notes.h')
| -rw-r--r-- | notes.h | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/notes.h b/notes.h new file mode 100644 index 0000000000..c716694b9e --- /dev/null +++ b/notes.h @@ -0,0 +1,315 @@ +#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 + +/* + * Fill the given strbuf with the notes associated with the given object. + * + * If the given notes_tree structure is not initialized, it will be auto- + * initialized to the default value (see documentation for init_notes() above). + * If the given notes_tree is NULL, the internal/default notes_tree will be + * used instead. + * + * 'flags' is a bitwise combination of the above formatting flags. + */ +void format_note(struct notes_tree *t, const unsigned char *object_sha1, + struct strbuf *sb, const char *output_encoding, int flags); + + +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 |