Merge branch 'ab/unused-annotation'
[git.git] / notes.c
blobf2805d51bb15131c46d41fa9554c43ab2e9a492d
1 #include "cache.h"
2 #include "config.h"
3 #include "notes.h"
4 #include "object-store.h"
5 #include "blob.h"
6 #include "tree.h"
7 #include "utf8.h"
8 #include "strbuf.h"
9 #include "tree-walk.h"
10 #include "string-list.h"
11 #include "refs.h"
14 * Use a non-balancing simple 16-tree structure with struct int_node as
15 * internal nodes, and struct leaf_node as leaf nodes. Each int_node has a
16 * 16-array of pointers to its children.
17 * The bottom 2 bits of each pointer is used to identify the pointer type
18 * - ptr & 3 == 0 - NULL pointer, assert(ptr == NULL)
19 * - ptr & 3 == 1 - pointer to next internal node - cast to struct int_node *
20 * - ptr & 3 == 2 - pointer to note entry - cast to struct leaf_node *
21 * - ptr & 3 == 3 - pointer to subtree entry - cast to struct leaf_node *
23 * The root node is a statically allocated struct int_node.
25 struct int_node {
26 void *a[16];
30 * Leaf nodes come in two variants, note entries and subtree entries,
31 * distinguished by the LSb of the leaf node pointer (see above).
32 * As a note entry, the key is the SHA1 of the referenced object, and the
33 * value is the SHA1 of the note object.
34 * As a subtree entry, the key is the prefix SHA1 (w/trailing NULs) of the
35 * referenced object, using the last byte of the key to store the length of
36 * the prefix. The value is the SHA1 of the tree object containing the notes
37 * subtree.
39 struct leaf_node {
40 struct object_id key_oid;
41 struct object_id val_oid;
45 * A notes tree may contain entries that are not notes, and that do not follow
46 * the naming conventions of notes. There are typically none/few of these, but
47 * we still need to keep track of them. Keep a simple linked list sorted alpha-
48 * betically on the non-note path. The list is populated when parsing tree
49 * objects in load_subtree(), and the non-notes are correctly written back into
50 * the tree objects produced by write_notes_tree().
52 struct non_note {
53 struct non_note *next; /* grounded (last->next == NULL) */
54 char *path;
55 unsigned int mode;
56 struct object_id oid;
59 #define PTR_TYPE_NULL 0
60 #define PTR_TYPE_INTERNAL 1
61 #define PTR_TYPE_NOTE 2
62 #define PTR_TYPE_SUBTREE 3
64 #define GET_PTR_TYPE(ptr) ((uintptr_t) (ptr) & 3)
65 #define CLR_PTR_TYPE(ptr) ((void *) ((uintptr_t) (ptr) & ~3))
66 #define SET_PTR_TYPE(ptr, type) ((void *) ((uintptr_t) (ptr) | (type)))
68 #define GET_NIBBLE(n, sha1) ((((sha1)[(n) >> 1]) >> ((~(n) & 0x01) << 2)) & 0x0f)
70 #define KEY_INDEX (the_hash_algo->rawsz - 1)
71 #define FANOUT_PATH_SEPARATORS (the_hash_algo->rawsz - 1)
72 #define FANOUT_PATH_SEPARATORS_MAX ((GIT_MAX_HEXSZ / 2) - 1)
73 #define SUBTREE_SHA1_PREFIXCMP(key_sha1, subtree_sha1) \
74 (memcmp(key_sha1, subtree_sha1, subtree_sha1[KEY_INDEX]))
76 struct notes_tree default_notes_tree;
78 static struct string_list display_notes_refs = STRING_LIST_INIT_NODUP;
79 static struct notes_tree **display_notes_trees;
81 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
82 struct int_node *node, unsigned int n);
85 * Search the tree until the appropriate location for the given key is found:
86 * 1. Start at the root node, with n = 0
87 * 2. If a[0] at the current level is a matching subtree entry, unpack that
88 * subtree entry and remove it; restart search at the current level.
89 * 3. Use the nth nibble of the key as an index into a:
90 * - If a[n] is an int_node, recurse from #2 into that node and increment n
91 * - If a matching subtree entry, unpack that subtree entry (and remove it);
92 * restart search at the current level.
93 * - Otherwise, we have found one of the following:
94 * - a subtree entry which does not match the key
95 * - a note entry which may or may not match the key
96 * - an unused leaf node (NULL)
97 * In any case, set *tree and *n, and return pointer to the tree location.
99 static void **note_tree_search(struct notes_tree *t, struct int_node **tree,
100 unsigned char *n, const unsigned char *key_sha1)
102 struct leaf_node *l;
103 unsigned char i;
104 void *p = (*tree)->a[0];
106 if (GET_PTR_TYPE(p) == PTR_TYPE_SUBTREE) {
107 l = (struct leaf_node *) CLR_PTR_TYPE(p);
108 if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
109 /* unpack tree and resume search */
110 (*tree)->a[0] = NULL;
111 load_subtree(t, l, *tree, *n);
112 free(l);
113 return note_tree_search(t, tree, n, key_sha1);
117 i = GET_NIBBLE(*n, key_sha1);
118 p = (*tree)->a[i];
119 switch (GET_PTR_TYPE(p)) {
120 case PTR_TYPE_INTERNAL:
121 *tree = CLR_PTR_TYPE(p);
122 (*n)++;
123 return note_tree_search(t, tree, n, key_sha1);
124 case PTR_TYPE_SUBTREE:
125 l = (struct leaf_node *) CLR_PTR_TYPE(p);
126 if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
127 /* unpack tree and resume search */
128 (*tree)->a[i] = NULL;
129 load_subtree(t, l, *tree, *n);
130 free(l);
131 return note_tree_search(t, tree, n, key_sha1);
133 /* fall through */
134 default:
135 return &((*tree)->a[i]);
140 * To find a leaf_node:
141 * Search to the tree location appropriate for the given key:
142 * If a note entry with matching key, return the note entry, else return NULL.
144 static struct leaf_node *note_tree_find(struct notes_tree *t,
145 struct int_node *tree, unsigned char n,
146 const unsigned char *key_sha1)
148 void **p = note_tree_search(t, &tree, &n, key_sha1);
149 if (GET_PTR_TYPE(*p) == PTR_TYPE_NOTE) {
150 struct leaf_node *l = (struct leaf_node *) CLR_PTR_TYPE(*p);
151 if (hasheq(key_sha1, l->key_oid.hash))
152 return l;
154 return NULL;
158 * How to consolidate an int_node:
159 * If there are > 1 non-NULL entries, give up and return non-zero.
160 * Otherwise replace the int_node at the given index in the given parent node
161 * with the only NOTE entry (or a NULL entry if no entries) from the given
162 * tree, and return 0.
164 static int note_tree_consolidate(struct int_node *tree,
165 struct int_node *parent, unsigned char index)
167 unsigned int i;
168 void *p = NULL;
170 assert(tree && parent);
171 assert(CLR_PTR_TYPE(parent->a[index]) == tree);
173 for (i = 0; i < 16; i++) {
174 if (GET_PTR_TYPE(tree->a[i]) != PTR_TYPE_NULL) {
175 if (p) /* more than one entry */
176 return -2;
177 p = tree->a[i];
181 if (p && (GET_PTR_TYPE(p) != PTR_TYPE_NOTE))
182 return -2;
183 /* replace tree with p in parent[index] */
184 parent->a[index] = p;
185 free(tree);
186 return 0;
190 * To remove a leaf_node:
191 * Search to the tree location appropriate for the given leaf_node's key:
192 * - If location does not hold a matching entry, abort and do nothing.
193 * - Copy the matching entry's value into the given entry.
194 * - Replace the matching leaf_node with a NULL entry (and free the leaf_node).
195 * - Consolidate int_nodes repeatedly, while walking up the tree towards root.
197 static void note_tree_remove(struct notes_tree *t,
198 struct int_node *tree, unsigned char n,
199 struct leaf_node *entry)
201 struct leaf_node *l;
202 struct int_node *parent_stack[GIT_MAX_RAWSZ];
203 unsigned char i, j;
204 void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
206 assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
207 if (GET_PTR_TYPE(*p) != PTR_TYPE_NOTE)
208 return; /* type mismatch, nothing to remove */
209 l = (struct leaf_node *) CLR_PTR_TYPE(*p);
210 if (!oideq(&l->key_oid, &entry->key_oid))
211 return; /* key mismatch, nothing to remove */
213 /* we have found a matching entry */
214 oidcpy(&entry->val_oid, &l->val_oid);
215 free(l);
216 *p = SET_PTR_TYPE(NULL, PTR_TYPE_NULL);
218 /* consolidate this tree level, and parent levels, if possible */
219 if (!n)
220 return; /* cannot consolidate top level */
221 /* first, build stack of ancestors between root and current node */
222 parent_stack[0] = t->root;
223 for (i = 0; i < n; i++) {
224 j = GET_NIBBLE(i, entry->key_oid.hash);
225 parent_stack[i + 1] = CLR_PTR_TYPE(parent_stack[i]->a[j]);
227 assert(i == n && parent_stack[i] == tree);
228 /* next, unwind stack until note_tree_consolidate() is done */
229 while (i > 0 &&
230 !note_tree_consolidate(parent_stack[i], parent_stack[i - 1],
231 GET_NIBBLE(i - 1, entry->key_oid.hash)))
232 i--;
236 * To insert a leaf_node:
237 * Search to the tree location appropriate for the given leaf_node's key:
238 * - If location is unused (NULL), store the tweaked pointer directly there
239 * - If location holds a note entry that matches the note-to-be-inserted, then
240 * combine the two notes (by calling the given combine_notes function).
241 * - If location holds a note entry that matches the subtree-to-be-inserted,
242 * then unpack the subtree-to-be-inserted into the location.
243 * - If location holds a matching subtree entry, unpack the subtree at that
244 * location, and restart the insert operation from that level.
245 * - Else, create a new int_node, holding both the node-at-location and the
246 * node-to-be-inserted, and store the new int_node into the location.
248 static int note_tree_insert(struct notes_tree *t, struct int_node *tree,
249 unsigned char n, struct leaf_node *entry, unsigned char type,
250 combine_notes_fn combine_notes)
252 struct int_node *new_node;
253 struct leaf_node *l;
254 void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
255 int ret = 0;
257 assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
258 l = (struct leaf_node *) CLR_PTR_TYPE(*p);
259 switch (GET_PTR_TYPE(*p)) {
260 case PTR_TYPE_NULL:
261 assert(!*p);
262 if (is_null_oid(&entry->val_oid))
263 free(entry);
264 else
265 *p = SET_PTR_TYPE(entry, type);
266 return 0;
267 case PTR_TYPE_NOTE:
268 switch (type) {
269 case PTR_TYPE_NOTE:
270 if (oideq(&l->key_oid, &entry->key_oid)) {
271 /* skip concatenation if l == entry */
272 if (oideq(&l->val_oid, &entry->val_oid)) {
273 free(entry);
274 return 0;
277 ret = combine_notes(&l->val_oid,
278 &entry->val_oid);
279 if (!ret && is_null_oid(&l->val_oid))
280 note_tree_remove(t, tree, n, entry);
281 free(entry);
282 return ret;
284 break;
285 case PTR_TYPE_SUBTREE:
286 if (!SUBTREE_SHA1_PREFIXCMP(l->key_oid.hash,
287 entry->key_oid.hash)) {
288 /* unpack 'entry' */
289 load_subtree(t, entry, tree, n);
290 free(entry);
291 return 0;
293 break;
295 break;
296 case PTR_TYPE_SUBTREE:
297 if (!SUBTREE_SHA1_PREFIXCMP(entry->key_oid.hash, l->key_oid.hash)) {
298 /* unpack 'l' and restart insert */
299 *p = NULL;
300 load_subtree(t, l, tree, n);
301 free(l);
302 return note_tree_insert(t, tree, n, entry, type,
303 combine_notes);
305 break;
308 /* non-matching leaf_node */
309 assert(GET_PTR_TYPE(*p) == PTR_TYPE_NOTE ||
310 GET_PTR_TYPE(*p) == PTR_TYPE_SUBTREE);
311 if (is_null_oid(&entry->val_oid)) { /* skip insertion of empty note */
312 free(entry);
313 return 0;
315 new_node = (struct int_node *) xcalloc(1, sizeof(struct int_node));
316 ret = note_tree_insert(t, new_node, n + 1, l, GET_PTR_TYPE(*p),
317 combine_notes);
318 if (ret)
319 return ret;
320 *p = SET_PTR_TYPE(new_node, PTR_TYPE_INTERNAL);
321 return note_tree_insert(t, new_node, n + 1, entry, type, combine_notes);
324 /* Free the entire notes data contained in the given tree */
325 static void note_tree_free(struct int_node *tree)
327 unsigned int i;
328 for (i = 0; i < 16; i++) {
329 void *p = tree->a[i];
330 switch (GET_PTR_TYPE(p)) {
331 case PTR_TYPE_INTERNAL:
332 note_tree_free(CLR_PTR_TYPE(p));
333 /* fall through */
334 case PTR_TYPE_NOTE:
335 case PTR_TYPE_SUBTREE:
336 free(CLR_PTR_TYPE(p));
341 static int non_note_cmp(const struct non_note *a, const struct non_note *b)
343 return strcmp(a->path, b->path);
346 /* note: takes ownership of path string */
347 static void add_non_note(struct notes_tree *t, char *path,
348 unsigned int mode, const unsigned char *sha1)
350 struct non_note *p = t->prev_non_note, *n;
351 n = (struct non_note *) xmalloc(sizeof(struct non_note));
352 n->next = NULL;
353 n->path = path;
354 n->mode = mode;
355 oidread(&n->oid, sha1);
356 t->prev_non_note = n;
358 if (!t->first_non_note) {
359 t->first_non_note = n;
360 return;
363 if (non_note_cmp(p, n) < 0)
364 ; /* do nothing */
365 else if (non_note_cmp(t->first_non_note, n) <= 0)
366 p = t->first_non_note;
367 else {
368 /* n sorts before t->first_non_note */
369 n->next = t->first_non_note;
370 t->first_non_note = n;
371 return;
374 /* n sorts equal or after p */
375 while (p->next && non_note_cmp(p->next, n) <= 0)
376 p = p->next;
378 if (non_note_cmp(p, n) == 0) { /* n ~= p; overwrite p with n */
379 assert(strcmp(p->path, n->path) == 0);
380 p->mode = n->mode;
381 oidcpy(&p->oid, &n->oid);
382 free(n);
383 t->prev_non_note = p;
384 return;
387 /* n sorts between p and p->next */
388 n->next = p->next;
389 p->next = n;
392 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
393 struct int_node *node, unsigned int n)
395 struct object_id object_oid;
396 size_t prefix_len;
397 void *buf;
398 struct tree_desc desc;
399 struct name_entry entry;
400 const unsigned hashsz = the_hash_algo->rawsz;
402 buf = fill_tree_descriptor(the_repository, &desc, &subtree->val_oid);
403 if (!buf)
404 die("Could not read %s for notes-index",
405 oid_to_hex(&subtree->val_oid));
407 prefix_len = subtree->key_oid.hash[KEY_INDEX];
408 if (prefix_len >= hashsz)
409 BUG("prefix_len (%"PRIuMAX") is out of range", (uintmax_t)prefix_len);
410 if (prefix_len * 2 < n)
411 BUG("prefix_len (%"PRIuMAX") is too small", (uintmax_t)prefix_len);
412 memcpy(object_oid.hash, subtree->key_oid.hash, prefix_len);
413 while (tree_entry(&desc, &entry)) {
414 unsigned char type;
415 struct leaf_node *l;
416 size_t path_len = strlen(entry.path);
418 if (path_len == 2 * (hashsz - prefix_len)) {
419 /* This is potentially the remainder of the SHA-1 */
421 if (!S_ISREG(entry.mode))
422 /* notes must be blobs */
423 goto handle_non_note;
425 if (hex_to_bytes(object_oid.hash + prefix_len, entry.path,
426 hashsz - prefix_len))
427 goto handle_non_note; /* entry.path is not a SHA1 */
429 type = PTR_TYPE_NOTE;
430 } else if (path_len == 2) {
431 /* This is potentially an internal node */
432 size_t len = prefix_len;
434 if (!S_ISDIR(entry.mode))
435 /* internal nodes must be trees */
436 goto handle_non_note;
438 if (hex_to_bytes(object_oid.hash + len++, entry.path, 1))
439 goto handle_non_note; /* entry.path is not a SHA1 */
442 * Pad the rest of the SHA-1 with zeros,
443 * except for the last byte, where we write
444 * the length:
446 memset(object_oid.hash + len, 0, hashsz - len - 1);
447 object_oid.hash[KEY_INDEX] = (unsigned char)len;
449 type = PTR_TYPE_SUBTREE;
450 } else {
451 /* This can't be part of a note */
452 goto handle_non_note;
455 CALLOC_ARRAY(l, 1);
456 oidcpy(&l->key_oid, &object_oid);
457 oidcpy(&l->val_oid, &entry.oid);
458 oid_set_algo(&l->key_oid, the_hash_algo);
459 oid_set_algo(&l->val_oid, the_hash_algo);
460 if (note_tree_insert(t, node, n, l, type,
461 combine_notes_concatenate))
462 die("Failed to load %s %s into notes tree "
463 "from %s",
464 type == PTR_TYPE_NOTE ? "note" : "subtree",
465 oid_to_hex(&object_oid), t->ref);
467 continue;
469 handle_non_note:
471 * Determine full path for this non-note entry. The
472 * filename is already found in entry.path, but the
473 * directory part of the path must be deduced from the
474 * subtree containing this entry based on our
475 * knowledge that the overall notes tree follows a
476 * strict byte-based progressive fanout structure
477 * (i.e. using 2/38, 2/2/36, etc. fanouts).
480 struct strbuf non_note_path = STRBUF_INIT;
481 const char *q = oid_to_hex(&subtree->key_oid);
482 size_t i;
483 for (i = 0; i < prefix_len; i++) {
484 strbuf_addch(&non_note_path, *q++);
485 strbuf_addch(&non_note_path, *q++);
486 strbuf_addch(&non_note_path, '/');
488 strbuf_addstr(&non_note_path, entry.path);
489 oid_set_algo(&entry.oid, the_hash_algo);
490 add_non_note(t, strbuf_detach(&non_note_path, NULL),
491 entry.mode, entry.oid.hash);
494 free(buf);
498 * Determine optimal on-disk fanout for this part of the notes tree
500 * Given a (sub)tree and the level in the internal tree structure, determine
501 * whether or not the given existing fanout should be expanded for this
502 * (sub)tree.
504 * Values of the 'fanout' variable:
505 * - 0: No fanout (all notes are stored directly in the root notes tree)
506 * - 1: 2/38 fanout
507 * - 2: 2/2/36 fanout
508 * - 3: 2/2/2/34 fanout
509 * etc.
511 static unsigned char determine_fanout(struct int_node *tree, unsigned char n,
512 unsigned char fanout)
515 * The following is a simple heuristic that works well in practice:
516 * For each even-numbered 16-tree level (remember that each on-disk
517 * fanout level corresponds to _two_ 16-tree levels), peek at all 16
518 * entries at that tree level. If all of them are either int_nodes or
519 * subtree entries, then there are likely plenty of notes below this
520 * level, so we return an incremented fanout.
522 unsigned int i;
523 if ((n % 2) || (n > 2 * fanout))
524 return fanout;
525 for (i = 0; i < 16; i++) {
526 switch (GET_PTR_TYPE(tree->a[i])) {
527 case PTR_TYPE_SUBTREE:
528 case PTR_TYPE_INTERNAL:
529 continue;
530 default:
531 return fanout;
534 return fanout + 1;
537 /* hex oid + '/' between each pair of hex digits + NUL */
538 #define FANOUT_PATH_MAX GIT_MAX_HEXSZ + FANOUT_PATH_SEPARATORS_MAX + 1
540 static void construct_path_with_fanout(const unsigned char *hash,
541 unsigned char fanout, char *path)
543 unsigned int i = 0, j = 0;
544 const char *hex_hash = hash_to_hex(hash);
545 assert(fanout < the_hash_algo->rawsz);
546 while (fanout) {
547 path[i++] = hex_hash[j++];
548 path[i++] = hex_hash[j++];
549 path[i++] = '/';
550 fanout--;
552 xsnprintf(path + i, FANOUT_PATH_MAX - i, "%s", hex_hash + j);
555 static int for_each_note_helper(struct notes_tree *t, struct int_node *tree,
556 unsigned char n, unsigned char fanout, int flags,
557 each_note_fn fn, void *cb_data)
559 unsigned int i;
560 void *p;
561 int ret = 0;
562 struct leaf_node *l;
563 static char path[FANOUT_PATH_MAX];
565 fanout = determine_fanout(tree, n, fanout);
566 for (i = 0; i < 16; i++) {
567 redo:
568 p = tree->a[i];
569 switch (GET_PTR_TYPE(p)) {
570 case PTR_TYPE_INTERNAL:
571 /* recurse into int_node */
572 ret = for_each_note_helper(t, CLR_PTR_TYPE(p), n + 1,
573 fanout, flags, fn, cb_data);
574 break;
575 case PTR_TYPE_SUBTREE:
576 l = (struct leaf_node *) CLR_PTR_TYPE(p);
578 * Subtree entries in the note tree represent parts of
579 * the note tree that have not yet been explored. There
580 * is a direct relationship between subtree entries at
581 * level 'n' in the tree, and the 'fanout' variable:
582 * Subtree entries at level 'n < 2 * fanout' should be
583 * preserved, since they correspond exactly to a fanout
584 * directory in the on-disk structure. However, subtree
585 * entries at level 'n >= 2 * fanout' should NOT be
586 * preserved, but rather consolidated into the above
587 * notes tree level. We achieve this by unconditionally
588 * unpacking subtree entries that exist below the
589 * threshold level at 'n = 2 * fanout'.
591 if (n < 2 * fanout &&
592 flags & FOR_EACH_NOTE_YIELD_SUBTREES) {
593 /* invoke callback with subtree */
594 unsigned int path_len =
595 l->key_oid.hash[KEY_INDEX] * 2 + fanout;
596 assert(path_len < FANOUT_PATH_MAX - 1);
597 construct_path_with_fanout(l->key_oid.hash,
598 fanout,
599 path);
600 /* Create trailing slash, if needed */
601 if (path[path_len - 1] != '/')
602 path[path_len++] = '/';
603 path[path_len] = '\0';
604 ret = fn(&l->key_oid, &l->val_oid,
605 path,
606 cb_data);
608 if (n >= 2 * fanout ||
609 !(flags & FOR_EACH_NOTE_DONT_UNPACK_SUBTREES)) {
610 /* unpack subtree and resume traversal */
611 tree->a[i] = NULL;
612 load_subtree(t, l, tree, n);
613 free(l);
614 goto redo;
616 break;
617 case PTR_TYPE_NOTE:
618 l = (struct leaf_node *) CLR_PTR_TYPE(p);
619 construct_path_with_fanout(l->key_oid.hash, fanout,
620 path);
621 ret = fn(&l->key_oid, &l->val_oid, path,
622 cb_data);
623 break;
625 if (ret)
626 return ret;
628 return 0;
631 struct tree_write_stack {
632 struct tree_write_stack *next;
633 struct strbuf buf;
634 char path[2]; /* path to subtree in next, if any */
637 static inline int matches_tree_write_stack(struct tree_write_stack *tws,
638 const char *full_path)
640 return full_path[0] == tws->path[0] &&
641 full_path[1] == tws->path[1] &&
642 full_path[2] == '/';
645 static void write_tree_entry(struct strbuf *buf, unsigned int mode,
646 const char *path, unsigned int path_len, const
647 unsigned char *hash)
649 strbuf_addf(buf, "%o %.*s%c", mode, path_len, path, '\0');
650 strbuf_add(buf, hash, the_hash_algo->rawsz);
653 static void tree_write_stack_init_subtree(struct tree_write_stack *tws,
654 const char *path)
656 struct tree_write_stack *n;
657 assert(!tws->next);
658 assert(tws->path[0] == '\0' && tws->path[1] == '\0');
659 n = (struct tree_write_stack *)
660 xmalloc(sizeof(struct tree_write_stack));
661 n->next = NULL;
662 strbuf_init(&n->buf, 256 * (32 + the_hash_algo->hexsz)); /* assume 256 entries per tree */
663 n->path[0] = n->path[1] = '\0';
664 tws->next = n;
665 tws->path[0] = path[0];
666 tws->path[1] = path[1];
669 static int tree_write_stack_finish_subtree(struct tree_write_stack *tws)
671 int ret;
672 struct tree_write_stack *n = tws->next;
673 struct object_id s;
674 if (n) {
675 ret = tree_write_stack_finish_subtree(n);
676 if (ret)
677 return ret;
678 ret = write_object_file(n->buf.buf, n->buf.len, OBJ_TREE, &s);
679 if (ret)
680 return ret;
681 strbuf_release(&n->buf);
682 free(n);
683 tws->next = NULL;
684 write_tree_entry(&tws->buf, 040000, tws->path, 2, s.hash);
685 tws->path[0] = tws->path[1] = '\0';
687 return 0;
690 static int write_each_note_helper(struct tree_write_stack *tws,
691 const char *path, unsigned int mode,
692 const struct object_id *oid)
694 size_t path_len = strlen(path);
695 unsigned int n = 0;
696 int ret;
698 /* Determine common part of tree write stack */
699 while (tws && 3 * n < path_len &&
700 matches_tree_write_stack(tws, path + 3 * n)) {
701 n++;
702 tws = tws->next;
705 /* tws point to last matching tree_write_stack entry */
706 ret = tree_write_stack_finish_subtree(tws);
707 if (ret)
708 return ret;
710 /* Start subtrees needed to satisfy path */
711 while (3 * n + 2 < path_len && path[3 * n + 2] == '/') {
712 tree_write_stack_init_subtree(tws, path + 3 * n);
713 n++;
714 tws = tws->next;
717 /* There should be no more directory components in the given path */
718 assert(memchr(path + 3 * n, '/', path_len - (3 * n)) == NULL);
720 /* Finally add given entry to the current tree object */
721 write_tree_entry(&tws->buf, mode, path + 3 * n, path_len - (3 * n),
722 oid->hash);
724 return 0;
727 struct write_each_note_data {
728 struct tree_write_stack *root;
729 struct non_note **nn_list;
730 struct non_note *nn_prev;
733 static int write_each_non_note_until(const char *note_path,
734 struct write_each_note_data *d)
736 struct non_note *p = d->nn_prev;
737 struct non_note *n = p ? p->next : *d->nn_list;
738 int cmp = 0, ret;
739 while (n && (!note_path || (cmp = strcmp(n->path, note_path)) <= 0)) {
740 if (note_path && cmp == 0)
741 ; /* do nothing, prefer note to non-note */
742 else {
743 ret = write_each_note_helper(d->root, n->path, n->mode,
744 &n->oid);
745 if (ret)
746 return ret;
748 p = n;
749 n = n->next;
751 d->nn_prev = p;
752 return 0;
755 static int write_each_note(const struct object_id *object_oid,
756 const struct object_id *note_oid, char *note_path,
757 void *cb_data)
759 struct write_each_note_data *d =
760 (struct write_each_note_data *) cb_data;
761 size_t note_path_len = strlen(note_path);
762 unsigned int mode = 0100644;
764 if (note_path[note_path_len - 1] == '/') {
765 /* subtree entry */
766 note_path_len--;
767 note_path[note_path_len] = '\0';
768 mode = 040000;
770 assert(note_path_len <= GIT_MAX_HEXSZ + FANOUT_PATH_SEPARATORS);
772 /* Weave non-note entries into note entries */
773 return write_each_non_note_until(note_path, d) ||
774 write_each_note_helper(d->root, note_path, mode, note_oid);
777 struct note_delete_list {
778 struct note_delete_list *next;
779 const unsigned char *sha1;
782 static int prune_notes_helper(const struct object_id *object_oid,
783 const struct object_id *note_oid, char *note_path,
784 void *cb_data)
786 struct note_delete_list **l = (struct note_delete_list **) cb_data;
787 struct note_delete_list *n;
789 if (has_object_file(object_oid))
790 return 0; /* nothing to do for this note */
792 /* failed to find object => prune this note */
793 n = (struct note_delete_list *) xmalloc(sizeof(*n));
794 n->next = *l;
795 n->sha1 = object_oid->hash;
796 *l = n;
797 return 0;
800 int combine_notes_concatenate(struct object_id *cur_oid,
801 const struct object_id *new_oid)
803 char *cur_msg = NULL, *new_msg = NULL, *buf;
804 unsigned long cur_len, new_len, buf_len;
805 enum object_type cur_type, new_type;
806 int ret;
808 /* read in both note blob objects */
809 if (!is_null_oid(new_oid))
810 new_msg = read_object_file(new_oid, &new_type, &new_len);
811 if (!new_msg || !new_len || new_type != OBJ_BLOB) {
812 free(new_msg);
813 return 0;
815 if (!is_null_oid(cur_oid))
816 cur_msg = read_object_file(cur_oid, &cur_type, &cur_len);
817 if (!cur_msg || !cur_len || cur_type != OBJ_BLOB) {
818 free(cur_msg);
819 free(new_msg);
820 oidcpy(cur_oid, new_oid);
821 return 0;
824 /* we will separate the notes by two newlines anyway */
825 if (cur_msg[cur_len - 1] == '\n')
826 cur_len--;
828 /* concatenate cur_msg and new_msg into buf */
829 buf_len = cur_len + 2 + new_len;
830 buf = (char *) xmalloc(buf_len);
831 memcpy(buf, cur_msg, cur_len);
832 buf[cur_len] = '\n';
833 buf[cur_len + 1] = '\n';
834 memcpy(buf + cur_len + 2, new_msg, new_len);
835 free(cur_msg);
836 free(new_msg);
838 /* create a new blob object from buf */
839 ret = write_object_file(buf, buf_len, OBJ_BLOB, cur_oid);
840 free(buf);
841 return ret;
844 int combine_notes_overwrite(struct object_id *cur_oid,
845 const struct object_id *new_oid)
847 oidcpy(cur_oid, new_oid);
848 return 0;
851 int combine_notes_ignore(struct object_id *cur_oid,
852 const struct object_id *new_oid)
854 return 0;
858 * Add the lines from the named object to list, with trailing
859 * newlines removed.
861 static int string_list_add_note_lines(struct string_list *list,
862 const struct object_id *oid)
864 char *data;
865 unsigned long len;
866 enum object_type t;
868 if (is_null_oid(oid))
869 return 0;
871 /* read_sha1_file NUL-terminates */
872 data = read_object_file(oid, &t, &len);
873 if (t != OBJ_BLOB || !data || !len) {
874 free(data);
875 return t != OBJ_BLOB || !data;
879 * If the last line of the file is EOL-terminated, this will
880 * add an empty string to the list. But it will be removed
881 * later, along with any empty strings that came from empty
882 * lines within the file.
884 string_list_split(list, data, '\n', -1);
885 free(data);
886 return 0;
889 static int string_list_join_lines_helper(struct string_list_item *item,
890 void *cb_data)
892 struct strbuf *buf = cb_data;
893 strbuf_addstr(buf, item->string);
894 strbuf_addch(buf, '\n');
895 return 0;
898 int combine_notes_cat_sort_uniq(struct object_id *cur_oid,
899 const struct object_id *new_oid)
901 struct string_list sort_uniq_list = STRING_LIST_INIT_DUP;
902 struct strbuf buf = STRBUF_INIT;
903 int ret = 1;
905 /* read both note blob objects into unique_lines */
906 if (string_list_add_note_lines(&sort_uniq_list, cur_oid))
907 goto out;
908 if (string_list_add_note_lines(&sort_uniq_list, new_oid))
909 goto out;
910 string_list_remove_empty_items(&sort_uniq_list, 0);
911 string_list_sort(&sort_uniq_list);
912 string_list_remove_duplicates(&sort_uniq_list, 0);
914 /* create a new blob object from sort_uniq_list */
915 if (for_each_string_list(&sort_uniq_list,
916 string_list_join_lines_helper, &buf))
917 goto out;
919 ret = write_object_file(buf.buf, buf.len, OBJ_BLOB, cur_oid);
921 out:
922 strbuf_release(&buf);
923 string_list_clear(&sort_uniq_list, 0);
924 return ret;
927 static int string_list_add_one_ref(const char *refname,
928 const struct object_id *oid UNUSED,
929 int flag UNUSED, void *cb)
931 struct string_list *refs = cb;
932 if (!unsorted_string_list_has_string(refs, refname))
933 string_list_append(refs, refname);
934 return 0;
938 * The list argument must have strdup_strings set on it.
940 void string_list_add_refs_by_glob(struct string_list *list, const char *glob)
942 assert(list->strdup_strings);
943 if (has_glob_specials(glob)) {
944 for_each_glob_ref(string_list_add_one_ref, glob, list);
945 } else {
946 struct object_id oid;
947 if (get_oid(glob, &oid))
948 warning("notes ref %s is invalid", glob);
949 if (!unsorted_string_list_has_string(list, glob))
950 string_list_append(list, glob);
954 void string_list_add_refs_from_colon_sep(struct string_list *list,
955 const char *globs)
957 struct string_list split = STRING_LIST_INIT_NODUP;
958 char *globs_copy = xstrdup(globs);
959 int i;
961 string_list_split_in_place(&split, globs_copy, ':', -1);
962 string_list_remove_empty_items(&split, 0);
964 for (i = 0; i < split.nr; i++)
965 string_list_add_refs_by_glob(list, split.items[i].string);
967 string_list_clear(&split, 0);
968 free(globs_copy);
971 static int notes_display_config(const char *k, const char *v, void *cb)
973 int *load_refs = cb;
975 if (*load_refs && !strcmp(k, "notes.displayref")) {
976 if (!v)
977 return config_error_nonbool(k);
978 string_list_add_refs_by_glob(&display_notes_refs, v);
981 return 0;
984 const char *default_notes_ref(void)
986 const char *notes_ref = NULL;
987 if (!notes_ref)
988 notes_ref = getenv(GIT_NOTES_REF_ENVIRONMENT);
989 if (!notes_ref)
990 notes_ref = notes_ref_name; /* value of core.notesRef config */
991 if (!notes_ref)
992 notes_ref = GIT_NOTES_DEFAULT_REF;
993 return notes_ref;
996 void init_notes(struct notes_tree *t, const char *notes_ref,
997 combine_notes_fn combine_notes, int flags)
999 struct object_id oid, object_oid;
1000 unsigned short mode;
1001 struct leaf_node root_tree;
1003 if (!t)
1004 t = &default_notes_tree;
1005 assert(!t->initialized);
1007 if (!notes_ref)
1008 notes_ref = default_notes_ref();
1009 update_ref_namespace(NAMESPACE_NOTES, xstrdup(notes_ref));
1011 if (!combine_notes)
1012 combine_notes = combine_notes_concatenate;
1014 t->root = (struct int_node *) xcalloc(1, sizeof(struct int_node));
1015 t->first_non_note = NULL;
1016 t->prev_non_note = NULL;
1017 t->ref = xstrdup_or_null(notes_ref);
1018 t->update_ref = (flags & NOTES_INIT_WRITABLE) ? t->ref : NULL;
1019 t->combine_notes = combine_notes;
1020 t->initialized = 1;
1021 t->dirty = 0;
1023 if (flags & NOTES_INIT_EMPTY || !notes_ref ||
1024 get_oid_treeish(notes_ref, &object_oid))
1025 return;
1026 if (flags & NOTES_INIT_WRITABLE && read_ref(notes_ref, &object_oid))
1027 die("Cannot use notes ref %s", notes_ref);
1028 if (get_tree_entry(the_repository, &object_oid, "", &oid, &mode))
1029 die("Failed to read notes tree referenced by %s (%s)",
1030 notes_ref, oid_to_hex(&object_oid));
1032 oidclr(&root_tree.key_oid);
1033 oidcpy(&root_tree.val_oid, &oid);
1034 load_subtree(t, &root_tree, t->root, 0);
1037 struct notes_tree **load_notes_trees(struct string_list *refs, int flags)
1039 struct string_list_item *item;
1040 int counter = 0;
1041 struct notes_tree **trees;
1042 ALLOC_ARRAY(trees, refs->nr + 1);
1043 for_each_string_list_item(item, refs) {
1044 struct notes_tree *t = xcalloc(1, sizeof(struct notes_tree));
1045 init_notes(t, item->string, combine_notes_ignore, flags);
1046 trees[counter++] = t;
1048 trees[counter] = NULL;
1049 return trees;
1052 void init_display_notes(struct display_notes_opt *opt)
1054 memset(opt, 0, sizeof(*opt));
1055 opt->use_default_notes = -1;
1058 void enable_default_display_notes(struct display_notes_opt *opt, int *show_notes)
1060 opt->use_default_notes = 1;
1061 *show_notes = 1;
1064 void enable_ref_display_notes(struct display_notes_opt *opt, int *show_notes,
1065 const char *ref) {
1066 struct strbuf buf = STRBUF_INIT;
1067 strbuf_addstr(&buf, ref);
1068 expand_notes_ref(&buf);
1069 string_list_append(&opt->extra_notes_refs,
1070 strbuf_detach(&buf, NULL));
1071 *show_notes = 1;
1074 void disable_display_notes(struct display_notes_opt *opt, int *show_notes)
1076 opt->use_default_notes = -1;
1077 /* we have been strdup'ing ourselves, so trick
1078 * string_list into free()ing strings */
1079 opt->extra_notes_refs.strdup_strings = 1;
1080 string_list_clear(&opt->extra_notes_refs, 0);
1081 opt->extra_notes_refs.strdup_strings = 0;
1082 *show_notes = 0;
1085 void load_display_notes(struct display_notes_opt *opt)
1087 char *display_ref_env;
1088 int load_config_refs = 0;
1089 display_notes_refs.strdup_strings = 1;
1091 assert(!display_notes_trees);
1093 if (!opt || opt->use_default_notes > 0 ||
1094 (opt->use_default_notes == -1 && !opt->extra_notes_refs.nr)) {
1095 string_list_append(&display_notes_refs, default_notes_ref());
1096 display_ref_env = getenv(GIT_NOTES_DISPLAY_REF_ENVIRONMENT);
1097 if (display_ref_env) {
1098 string_list_add_refs_from_colon_sep(&display_notes_refs,
1099 display_ref_env);
1100 load_config_refs = 0;
1101 } else
1102 load_config_refs = 1;
1105 git_config(notes_display_config, &load_config_refs);
1107 if (opt) {
1108 struct string_list_item *item;
1109 for_each_string_list_item(item, &opt->extra_notes_refs)
1110 string_list_add_refs_by_glob(&display_notes_refs,
1111 item->string);
1114 display_notes_trees = load_notes_trees(&display_notes_refs, 0);
1115 string_list_clear(&display_notes_refs, 0);
1118 int add_note(struct notes_tree *t, const struct object_id *object_oid,
1119 const struct object_id *note_oid, combine_notes_fn combine_notes)
1121 struct leaf_node *l;
1123 if (!t)
1124 t = &default_notes_tree;
1125 assert(t->initialized);
1126 t->dirty = 1;
1127 if (!combine_notes)
1128 combine_notes = t->combine_notes;
1129 l = (struct leaf_node *) xmalloc(sizeof(struct leaf_node));
1130 oidcpy(&l->key_oid, object_oid);
1131 oidcpy(&l->val_oid, note_oid);
1132 return note_tree_insert(t, t->root, 0, l, PTR_TYPE_NOTE, combine_notes);
1135 int remove_note(struct notes_tree *t, const unsigned char *object_sha1)
1137 struct leaf_node l;
1139 if (!t)
1140 t = &default_notes_tree;
1141 assert(t->initialized);
1142 oidread(&l.key_oid, object_sha1);
1143 oidclr(&l.val_oid);
1144 note_tree_remove(t, t->root, 0, &l);
1145 if (is_null_oid(&l.val_oid)) /* no note was removed */
1146 return 1;
1147 t->dirty = 1;
1148 return 0;
1151 const struct object_id *get_note(struct notes_tree *t,
1152 const struct object_id *oid)
1154 struct leaf_node *found;
1156 if (!t)
1157 t = &default_notes_tree;
1158 assert(t->initialized);
1159 found = note_tree_find(t, t->root, 0, oid->hash);
1160 return found ? &found->val_oid : NULL;
1163 int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
1164 void *cb_data)
1166 if (!t)
1167 t = &default_notes_tree;
1168 assert(t->initialized);
1169 return for_each_note_helper(t, t->root, 0, 0, flags, fn, cb_data);
1172 int write_notes_tree(struct notes_tree *t, struct object_id *result)
1174 struct tree_write_stack root;
1175 struct write_each_note_data cb_data;
1176 int ret;
1177 int flags;
1179 if (!t)
1180 t = &default_notes_tree;
1181 assert(t->initialized);
1183 /* Prepare for traversal of current notes tree */
1184 root.next = NULL; /* last forward entry in list is grounded */
1185 strbuf_init(&root.buf, 256 * (32 + the_hash_algo->hexsz)); /* assume 256 entries */
1186 root.path[0] = root.path[1] = '\0';
1187 cb_data.root = &root;
1188 cb_data.nn_list = &(t->first_non_note);
1189 cb_data.nn_prev = NULL;
1191 /* Write tree objects representing current notes tree */
1192 flags = FOR_EACH_NOTE_DONT_UNPACK_SUBTREES |
1193 FOR_EACH_NOTE_YIELD_SUBTREES;
1194 ret = for_each_note(t, flags, write_each_note, &cb_data) ||
1195 write_each_non_note_until(NULL, &cb_data) ||
1196 tree_write_stack_finish_subtree(&root) ||
1197 write_object_file(root.buf.buf, root.buf.len, OBJ_TREE, result);
1198 strbuf_release(&root.buf);
1199 return ret;
1202 void prune_notes(struct notes_tree *t, int flags)
1204 struct note_delete_list *l = NULL;
1206 if (!t)
1207 t = &default_notes_tree;
1208 assert(t->initialized);
1210 for_each_note(t, 0, prune_notes_helper, &l);
1212 while (l) {
1213 if (flags & NOTES_PRUNE_VERBOSE)
1214 printf("%s\n", hash_to_hex(l->sha1));
1215 if (!(flags & NOTES_PRUNE_DRYRUN))
1216 remove_note(t, l->sha1);
1217 l = l->next;
1221 void free_notes(struct notes_tree *t)
1223 if (!t)
1224 t = &default_notes_tree;
1225 if (t->root)
1226 note_tree_free(t->root);
1227 free(t->root);
1228 while (t->first_non_note) {
1229 t->prev_non_note = t->first_non_note->next;
1230 free(t->first_non_note->path);
1231 free(t->first_non_note);
1232 t->first_non_note = t->prev_non_note;
1234 free(t->ref);
1235 memset(t, 0, sizeof(struct notes_tree));
1239 * Fill the given strbuf with the notes associated with the given object.
1241 * If the given notes_tree structure is not initialized, it will be auto-
1242 * initialized to the default value (see documentation for init_notes() above).
1243 * If the given notes_tree is NULL, the internal/default notes_tree will be
1244 * used instead.
1246 * (raw != 0) gives the %N userformat; otherwise, the note message is given
1247 * for human consumption.
1249 static void format_note(struct notes_tree *t, const struct object_id *object_oid,
1250 struct strbuf *sb, const char *output_encoding, int raw)
1252 static const char utf8[] = "utf-8";
1253 const struct object_id *oid;
1254 char *msg, *msg_p;
1255 unsigned long linelen, msglen;
1256 enum object_type type;
1258 if (!t)
1259 t = &default_notes_tree;
1260 if (!t->initialized)
1261 init_notes(t, NULL, NULL, 0);
1263 oid = get_note(t, object_oid);
1264 if (!oid)
1265 return;
1267 if (!(msg = read_object_file(oid, &type, &msglen)) || type != OBJ_BLOB) {
1268 free(msg);
1269 return;
1272 if (output_encoding && *output_encoding &&
1273 !is_encoding_utf8(output_encoding)) {
1274 char *reencoded = reencode_string(msg, output_encoding, utf8);
1275 if (reencoded) {
1276 free(msg);
1277 msg = reencoded;
1278 msglen = strlen(msg);
1282 /* we will end the annotation by a newline anyway */
1283 if (msglen && msg[msglen - 1] == '\n')
1284 msglen--;
1286 if (!raw) {
1287 const char *ref = t->ref;
1288 if (!ref || !strcmp(ref, GIT_NOTES_DEFAULT_REF)) {
1289 strbuf_addstr(sb, "\nNotes:\n");
1290 } else {
1291 skip_prefix(ref, "refs/", &ref);
1292 skip_prefix(ref, "notes/", &ref);
1293 strbuf_addf(sb, "\nNotes (%s):\n", ref);
1297 for (msg_p = msg; msg_p < msg + msglen; msg_p += linelen + 1) {
1298 linelen = strchrnul(msg_p, '\n') - msg_p;
1300 if (!raw)
1301 strbuf_addstr(sb, " ");
1302 strbuf_add(sb, msg_p, linelen);
1303 strbuf_addch(sb, '\n');
1306 free(msg);
1309 void format_display_notes(const struct object_id *object_oid,
1310 struct strbuf *sb, const char *output_encoding, int raw)
1312 int i;
1313 assert(display_notes_trees);
1314 for (i = 0; display_notes_trees[i]; i++)
1315 format_note(display_notes_trees[i], object_oid, sb,
1316 output_encoding, raw);
1319 int copy_note(struct notes_tree *t,
1320 const struct object_id *from_obj, const struct object_id *to_obj,
1321 int force, combine_notes_fn combine_notes)
1323 const struct object_id *note = get_note(t, from_obj);
1324 const struct object_id *existing_note = get_note(t, to_obj);
1326 if (!force && existing_note)
1327 return 1;
1329 if (note)
1330 return add_note(t, to_obj, note, combine_notes);
1331 else if (existing_note)
1332 return add_note(t, to_obj, null_oid(), combine_notes);
1334 return 0;
1337 void expand_notes_ref(struct strbuf *sb)
1339 if (starts_with(sb->buf, "refs/notes/"))
1340 return; /* we're happy */
1341 else if (starts_with(sb->buf, "notes/"))
1342 strbuf_insertstr(sb, 0, "refs/");
1343 else
1344 strbuf_insertstr(sb, 0, "refs/notes/");
1347 void expand_loose_notes_ref(struct strbuf *sb)
1349 struct object_id object;
1351 if (get_oid(sb->buf, &object)) {
1352 /* fallback to expand_notes_ref */
1353 expand_notes_ref(sb);