Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 318 insertions, 0 deletions

diff --git a/notes.h b/notes.h
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+#ifndef NOTES_H
+#define NOTES_H
+
+#include "string-list.h"
+
+struct object_id;
+struct strbuf;
+
+/*
+ * 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 object_ids -- 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 oid into the first argument (cur_oid). A non-zero return
+ * value indicates failure.
+ *
+ * The two given object_ids shall both be non-NULL and different from each
+ * other. Either of them (but not both) may be == null_oid, which indicates an
+ * empty/non-existent note. If the resulting oid (cur_oid) is == null_oid,
+ * 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)(struct object_id *cur_oid,
+				const struct object_id *new_oid);
+
+/* Common notes combinators */
+int combine_notes_concatenate(struct object_id *cur_oid,
+			      const struct object_id *new_oid);
+int combine_notes_overwrite(struct object_id *cur_oid,
+			    const struct object_id *new_oid);
+int combine_notes_ignore(struct object_id *cur_oid,
+			 const struct object_id *new_oid);
+int combine_notes_cat_sort_uniq(struct object_id *cur_oid,
+				const struct object_id *new_oid);
+
+/*
+ * 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;
+	char *update_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
+
+/*
+ * By default, the notes tree is only readable, and the notes ref can be
+ * any treeish. The notes tree can however be made writable with this flag,
+ * in which case only strict ref names can be used.
+ */
+#define NOTES_INIT_WRITABLE 2
+
+/*
+ * 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-initialize 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 struct object_id *object_oid,
+		const struct object_id *note_oid, 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 struct object_id *get_note(struct notes_tree *t,
+		const struct object_id *object_oid);
+
+/*
+ * 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 struct object_id *from_obj, const struct object_id *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 struct object_id *object_oid,
+		const struct object_id *note_oid, 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 object id 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, struct object_id *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);
+
+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'.
+ *
+ * If 'raw' is false the note will be indented by 4 places and
+ * a 'Notes (refname):' header added.
+ *
+ * You *must* call init_display_notes() before using this function.
+ */
+void format_display_notes(const struct object_id *object_oid,
+			  struct strbuf *sb, const char *output_encoding, int raw);
+
+/*
+ * 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, int flags);
+
+/*
+ * 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);
+
+/*
+ * Similar to expand_notes_ref, but will check whether the ref can be located
+ * via get_sha1 first, and only falls back to expand_notes_ref in the case
+ * where get_sha1 fails.
+ */
+void expand_loose_notes_ref(struct strbuf *sb);
+
+#endif