Merge branch 'jt/http-redact-cookies' into maint
[git.git] / notes.c
blobc7f21fae441067f7250caf0b4186fcbcbc7630bb
1 #include "cache.h"
2 #include "config.h"
3 #include "notes.h"
4 #include "blob.h"
5 #include "tree.h"
6 #include "utf8.h"
7 #include "strbuf.h"
8 #include "tree-walk.h"
9 #include "string-list.h"
10 #include "refs.h"
13 * Use a non-balancing simple 16-tree structure with struct int_node as
14 * internal nodes, and struct leaf_node as leaf nodes. Each int_node has a
15 * 16-array of pointers to its children.
16 * The bottom 2 bits of each pointer is used to identify the pointer type
17 * - ptr & 3 == 0 - NULL pointer, assert(ptr == NULL)
18 * - ptr & 3 == 1 - pointer to next internal node - cast to struct int_node *
19 * - ptr & 3 == 2 - pointer to note entry - cast to struct leaf_node *
20 * - ptr & 3 == 3 - pointer to subtree entry - cast to struct leaf_node *
22 * The root node is a statically allocated struct int_node.
24 struct int_node {
25 void *a[16];
29 * Leaf nodes come in two variants, note entries and subtree entries,
30 * distinguished by the LSb of the leaf node pointer (see above).
31 * As a note entry, the key is the SHA1 of the referenced object, and the
32 * value is the SHA1 of the note object.
33 * As a subtree entry, the key is the prefix SHA1 (w/trailing NULs) of the
34 * referenced object, using the last byte of the key to store the length of
35 * the prefix. The value is the SHA1 of the tree object containing the notes
36 * subtree.
38 struct leaf_node {
39 struct object_id key_oid;
40 struct object_id val_oid;
44 * A notes tree may contain entries that are not notes, and that do not follow
45 * the naming conventions of notes. There are typically none/few of these, but
46 * we still need to keep track of them. Keep a simple linked list sorted alpha-
47 * betically on the non-note path. The list is populated when parsing tree
48 * objects in load_subtree(), and the non-notes are correctly written back into
49 * the tree objects produced by write_notes_tree().
51 struct non_note {
52 struct non_note *next; /* grounded (last->next == NULL) */
53 char *path;
54 unsigned int mode;
55 struct object_id oid;
58 #define PTR_TYPE_NULL 0
59 #define PTR_TYPE_INTERNAL 1
60 #define PTR_TYPE_NOTE 2
61 #define PTR_TYPE_SUBTREE 3
63 #define GET_PTR_TYPE(ptr) ((uintptr_t) (ptr) & 3)
64 #define CLR_PTR_TYPE(ptr) ((void *) ((uintptr_t) (ptr) & ~3))
65 #define SET_PTR_TYPE(ptr, type) ((void *) ((uintptr_t) (ptr) | (type)))
67 #define GET_NIBBLE(n, sha1) ((((sha1)[(n) >> 1]) >> ((~(n) & 0x01) << 2)) & 0x0f)
69 #define KEY_INDEX (GIT_SHA1_RAWSZ - 1)
70 #define FANOUT_PATH_SEPARATORS ((GIT_SHA1_HEXSZ / 2) - 1)
71 #define SUBTREE_SHA1_PREFIXCMP(key_sha1, subtree_sha1) \
72 (memcmp(key_sha1, subtree_sha1, subtree_sha1[KEY_INDEX]))
74 struct notes_tree default_notes_tree;
76 static struct string_list display_notes_refs = STRING_LIST_INIT_NODUP;
77 static struct notes_tree **display_notes_trees;
79 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
80 struct int_node *node, unsigned int n);
83 * Search the tree until the appropriate location for the given key is found:
84 * 1. Start at the root node, with n = 0
85 * 2. If a[0] at the current level is a matching subtree entry, unpack that
86 * subtree entry and remove it; restart search at the current level.
87 * 3. Use the nth nibble of the key as an index into a:
88 * - If a[n] is an int_node, recurse from #2 into that node and increment n
89 * - If a matching subtree entry, unpack that subtree entry (and remove it);
90 * restart search at the current level.
91 * - Otherwise, we have found one of the following:
92 * - a subtree entry which does not match the key
93 * - a note entry which may or may not match the key
94 * - an unused leaf node (NULL)
95 * In any case, set *tree and *n, and return pointer to the tree location.
97 static void **note_tree_search(struct notes_tree *t, struct int_node **tree,
98 unsigned char *n, const unsigned char *key_sha1)
100 struct leaf_node *l;
101 unsigned char i;
102 void *p = (*tree)->a[0];
104 if (GET_PTR_TYPE(p) == PTR_TYPE_SUBTREE) {
105 l = (struct leaf_node *) CLR_PTR_TYPE(p);
106 if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
107 /* unpack tree and resume search */
108 (*tree)->a[0] = NULL;
109 load_subtree(t, l, *tree, *n);
110 free(l);
111 return note_tree_search(t, tree, n, key_sha1);
115 i = GET_NIBBLE(*n, key_sha1);
116 p = (*tree)->a[i];
117 switch (GET_PTR_TYPE(p)) {
118 case PTR_TYPE_INTERNAL:
119 *tree = CLR_PTR_TYPE(p);
120 (*n)++;
121 return note_tree_search(t, tree, n, key_sha1);
122 case PTR_TYPE_SUBTREE:
123 l = (struct leaf_node *) CLR_PTR_TYPE(p);
124 if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
125 /* unpack tree and resume search */
126 (*tree)->a[i] = NULL;
127 load_subtree(t, l, *tree, *n);
128 free(l);
129 return note_tree_search(t, tree, n, key_sha1);
131 /* fall through */
132 default:
133 return &((*tree)->a[i]);
138 * To find a leaf_node:
139 * Search to the tree location appropriate for the given key:
140 * If a note entry with matching key, return the note entry, else return NULL.
142 static struct leaf_node *note_tree_find(struct notes_tree *t,
143 struct int_node *tree, unsigned char n,
144 const unsigned char *key_sha1)
146 void **p = note_tree_search(t, &tree, &n, key_sha1);
147 if (GET_PTR_TYPE(*p) == PTR_TYPE_NOTE) {
148 struct leaf_node *l = (struct leaf_node *) CLR_PTR_TYPE(*p);
149 if (!hashcmp(key_sha1, l->key_oid.hash))
150 return l;
152 return NULL;
156 * How to consolidate an int_node:
157 * If there are > 1 non-NULL entries, give up and return non-zero.
158 * Otherwise replace the int_node at the given index in the given parent node
159 * with the only NOTE entry (or a NULL entry if no entries) from the given
160 * tree, and return 0.
162 static int note_tree_consolidate(struct int_node *tree,
163 struct int_node *parent, unsigned char index)
165 unsigned int i;
166 void *p = NULL;
168 assert(tree && parent);
169 assert(CLR_PTR_TYPE(parent->a[index]) == tree);
171 for (i = 0; i < 16; i++) {
172 if (GET_PTR_TYPE(tree->a[i]) != PTR_TYPE_NULL) {
173 if (p) /* more than one entry */
174 return -2;
175 p = tree->a[i];
179 if (p && (GET_PTR_TYPE(p) != PTR_TYPE_NOTE))
180 return -2;
181 /* replace tree with p in parent[index] */
182 parent->a[index] = p;
183 free(tree);
184 return 0;
188 * To remove a leaf_node:
189 * Search to the tree location appropriate for the given leaf_node's key:
190 * - If location does not hold a matching entry, abort and do nothing.
191 * - Copy the matching entry's value into the given entry.
192 * - Replace the matching leaf_node with a NULL entry (and free the leaf_node).
193 * - Consolidate int_nodes repeatedly, while walking up the tree towards root.
195 static void note_tree_remove(struct notes_tree *t,
196 struct int_node *tree, unsigned char n,
197 struct leaf_node *entry)
199 struct leaf_node *l;
200 struct int_node *parent_stack[GIT_SHA1_RAWSZ];
201 unsigned char i, j;
202 void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
204 assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
205 if (GET_PTR_TYPE(*p) != PTR_TYPE_NOTE)
206 return; /* type mismatch, nothing to remove */
207 l = (struct leaf_node *) CLR_PTR_TYPE(*p);
208 if (oidcmp(&l->key_oid, &entry->key_oid))
209 return; /* key mismatch, nothing to remove */
211 /* we have found a matching entry */
212 oidcpy(&entry->val_oid, &l->val_oid);
213 free(l);
214 *p = SET_PTR_TYPE(NULL, PTR_TYPE_NULL);
216 /* consolidate this tree level, and parent levels, if possible */
217 if (!n)
218 return; /* cannot consolidate top level */
219 /* first, build stack of ancestors between root and current node */
220 parent_stack[0] = t->root;
221 for (i = 0; i < n; i++) {
222 j = GET_NIBBLE(i, entry->key_oid.hash);
223 parent_stack[i + 1] = CLR_PTR_TYPE(parent_stack[i]->a[j]);
225 assert(i == n && parent_stack[i] == tree);
226 /* next, unwind stack until note_tree_consolidate() is done */
227 while (i > 0 &&
228 !note_tree_consolidate(parent_stack[i], parent_stack[i - 1],
229 GET_NIBBLE(i - 1, entry->key_oid.hash)))
230 i--;
234 * To insert a leaf_node:
235 * Search to the tree location appropriate for the given leaf_node's key:
236 * - If location is unused (NULL), store the tweaked pointer directly there
237 * - If location holds a note entry that matches the note-to-be-inserted, then
238 * combine the two notes (by calling the given combine_notes function).
239 * - If location holds a note entry that matches the subtree-to-be-inserted,
240 * then unpack the subtree-to-be-inserted into the location.
241 * - If location holds a matching subtree entry, unpack the subtree at that
242 * location, and restart the insert operation from that level.
243 * - Else, create a new int_node, holding both the node-at-location and the
244 * node-to-be-inserted, and store the new int_node into the location.
246 static int note_tree_insert(struct notes_tree *t, struct int_node *tree,
247 unsigned char n, struct leaf_node *entry, unsigned char type,
248 combine_notes_fn combine_notes)
250 struct int_node *new_node;
251 struct leaf_node *l;
252 void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
253 int ret = 0;
255 assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
256 l = (struct leaf_node *) CLR_PTR_TYPE(*p);
257 switch (GET_PTR_TYPE(*p)) {
258 case PTR_TYPE_NULL:
259 assert(!*p);
260 if (is_null_oid(&entry->val_oid))
261 free(entry);
262 else
263 *p = SET_PTR_TYPE(entry, type);
264 return 0;
265 case PTR_TYPE_NOTE:
266 switch (type) {
267 case PTR_TYPE_NOTE:
268 if (!oidcmp(&l->key_oid, &entry->key_oid)) {
269 /* skip concatenation if l == entry */
270 if (!oidcmp(&l->val_oid, &entry->val_oid))
271 return 0;
273 ret = combine_notes(l->val_oid.hash,
274 entry->val_oid.hash);
275 if (!ret && is_null_oid(&l->val_oid))
276 note_tree_remove(t, tree, n, entry);
277 free(entry);
278 return ret;
280 break;
281 case PTR_TYPE_SUBTREE:
282 if (!SUBTREE_SHA1_PREFIXCMP(l->key_oid.hash,
283 entry->key_oid.hash)) {
284 /* unpack 'entry' */
285 load_subtree(t, entry, tree, n);
286 free(entry);
287 return 0;
289 break;
291 break;
292 case PTR_TYPE_SUBTREE:
293 if (!SUBTREE_SHA1_PREFIXCMP(entry->key_oid.hash, l->key_oid.hash)) {
294 /* unpack 'l' and restart insert */
295 *p = NULL;
296 load_subtree(t, l, tree, n);
297 free(l);
298 return note_tree_insert(t, tree, n, entry, type,
299 combine_notes);
301 break;
304 /* non-matching leaf_node */
305 assert(GET_PTR_TYPE(*p) == PTR_TYPE_NOTE ||
306 GET_PTR_TYPE(*p) == PTR_TYPE_SUBTREE);
307 if (is_null_oid(&entry->val_oid)) { /* skip insertion of empty note */
308 free(entry);
309 return 0;
311 new_node = (struct int_node *) xcalloc(1, sizeof(struct int_node));
312 ret = note_tree_insert(t, new_node, n + 1, l, GET_PTR_TYPE(*p),
313 combine_notes);
314 if (ret)
315 return ret;
316 *p = SET_PTR_TYPE(new_node, PTR_TYPE_INTERNAL);
317 return note_tree_insert(t, new_node, n + 1, entry, type, combine_notes);
320 /* Free the entire notes data contained in the given tree */
321 static void note_tree_free(struct int_node *tree)
323 unsigned int i;
324 for (i = 0; i < 16; i++) {
325 void *p = tree->a[i];
326 switch (GET_PTR_TYPE(p)) {
327 case PTR_TYPE_INTERNAL:
328 note_tree_free(CLR_PTR_TYPE(p));
329 /* fall through */
330 case PTR_TYPE_NOTE:
331 case PTR_TYPE_SUBTREE:
332 free(CLR_PTR_TYPE(p));
337 static int non_note_cmp(const struct non_note *a, const struct non_note *b)
339 return strcmp(a->path, b->path);
342 /* note: takes ownership of path string */
343 static void add_non_note(struct notes_tree *t, char *path,
344 unsigned int mode, const unsigned char *sha1)
346 struct non_note *p = t->prev_non_note, *n;
347 n = (struct non_note *) xmalloc(sizeof(struct non_note));
348 n->next = NULL;
349 n->path = path;
350 n->mode = mode;
351 hashcpy(n->oid.hash, sha1);
352 t->prev_non_note = n;
354 if (!t->first_non_note) {
355 t->first_non_note = n;
356 return;
359 if (non_note_cmp(p, n) < 0)
360 ; /* do nothing */
361 else if (non_note_cmp(t->first_non_note, n) <= 0)
362 p = t->first_non_note;
363 else {
364 /* n sorts before t->first_non_note */
365 n->next = t->first_non_note;
366 t->first_non_note = n;
367 return;
370 /* n sorts equal or after p */
371 while (p->next && non_note_cmp(p->next, n) <= 0)
372 p = p->next;
374 if (non_note_cmp(p, n) == 0) { /* n ~= p; overwrite p with n */
375 assert(strcmp(p->path, n->path) == 0);
376 p->mode = n->mode;
377 oidcpy(&p->oid, &n->oid);
378 free(n);
379 t->prev_non_note = p;
380 return;
383 /* n sorts between p and p->next */
384 n->next = p->next;
385 p->next = n;
388 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
389 struct int_node *node, unsigned int n)
391 struct object_id object_oid;
392 size_t prefix_len;
393 void *buf;
394 struct tree_desc desc;
395 struct name_entry entry;
397 buf = fill_tree_descriptor(&desc, &subtree->val_oid);
398 if (!buf)
399 die("Could not read %s for notes-index",
400 oid_to_hex(&subtree->val_oid));
402 prefix_len = subtree->key_oid.hash[KEY_INDEX];
403 if (prefix_len >= GIT_SHA1_RAWSZ)
404 BUG("prefix_len (%"PRIuMAX") is out of range", (uintmax_t)prefix_len);
405 if (prefix_len * 2 < n)
406 BUG("prefix_len (%"PRIuMAX") is too small", (uintmax_t)prefix_len);
407 memcpy(object_oid.hash, subtree->key_oid.hash, prefix_len);
408 while (tree_entry(&desc, &entry)) {
409 unsigned char type;
410 struct leaf_node *l;
411 size_t path_len = strlen(entry.path);
413 if (path_len == 2 * (GIT_SHA1_RAWSZ - prefix_len)) {
414 /* This is potentially the remainder of the SHA-1 */
416 if (!S_ISREG(entry.mode))
417 /* notes must be blobs */
418 goto handle_non_note;
420 if (hex_to_bytes(object_oid.hash + prefix_len, entry.path,
421 GIT_SHA1_RAWSZ - prefix_len))
422 goto handle_non_note; /* entry.path is not a SHA1 */
424 type = PTR_TYPE_NOTE;
425 } else if (path_len == 2) {
426 /* This is potentially an internal node */
427 size_t len = prefix_len;
429 if (!S_ISDIR(entry.mode))
430 /* internal nodes must be trees */
431 goto handle_non_note;
433 if (hex_to_bytes(object_oid.hash + len++, entry.path, 1))
434 goto handle_non_note; /* entry.path is not a SHA1 */
437 * Pad the rest of the SHA-1 with zeros,
438 * except for the last byte, where we write
439 * the length:
441 memset(object_oid.hash + len, 0, GIT_SHA1_RAWSZ - len - 1);
442 object_oid.hash[KEY_INDEX] = (unsigned char)len;
444 type = PTR_TYPE_SUBTREE;
445 } else {
446 /* This can't be part of a note */
447 goto handle_non_note;
450 l = xcalloc(1, sizeof(*l));
451 oidcpy(&l->key_oid, &object_oid);
452 oidcpy(&l->val_oid, entry.oid);
453 if (note_tree_insert(t, node, n, l, type,
454 combine_notes_concatenate))
455 die("Failed to load %s %s into notes tree "
456 "from %s",
457 type == PTR_TYPE_NOTE ? "note" : "subtree",
458 oid_to_hex(&l->key_oid), t->ref);
460 continue;
462 handle_non_note:
464 * Determine full path for this non-note entry. The
465 * filename is already found in entry.path, but the
466 * directory part of the path must be deduced from the
467 * subtree containing this entry based on our
468 * knowledge that the overall notes tree follows a
469 * strict byte-based progressive fanout structure
470 * (i.e. using 2/38, 2/2/36, etc. fanouts).
473 struct strbuf non_note_path = STRBUF_INIT;
474 const char *q = oid_to_hex(&subtree->key_oid);
475 size_t i;
476 for (i = 0; i < prefix_len; i++) {
477 strbuf_addch(&non_note_path, *q++);
478 strbuf_addch(&non_note_path, *q++);
479 strbuf_addch(&non_note_path, '/');
481 strbuf_addstr(&non_note_path, entry.path);
482 add_non_note(t, strbuf_detach(&non_note_path, NULL),
483 entry.mode, entry.oid->hash);
486 free(buf);
490 * Determine optimal on-disk fanout for this part of the notes tree
492 * Given a (sub)tree and the level in the internal tree structure, determine
493 * whether or not the given existing fanout should be expanded for this
494 * (sub)tree.
496 * Values of the 'fanout' variable:
497 * - 0: No fanout (all notes are stored directly in the root notes tree)
498 * - 1: 2/38 fanout
499 * - 2: 2/2/36 fanout
500 * - 3: 2/2/2/34 fanout
501 * etc.
503 static unsigned char determine_fanout(struct int_node *tree, unsigned char n,
504 unsigned char fanout)
507 * The following is a simple heuristic that works well in practice:
508 * For each even-numbered 16-tree level (remember that each on-disk
509 * fanout level corresponds to _two_ 16-tree levels), peek at all 16
510 * entries at that tree level. If all of them are either int_nodes or
511 * subtree entries, then there are likely plenty of notes below this
512 * level, so we return an incremented fanout.
514 unsigned int i;
515 if ((n % 2) || (n > 2 * fanout))
516 return fanout;
517 for (i = 0; i < 16; i++) {
518 switch (GET_PTR_TYPE(tree->a[i])) {
519 case PTR_TYPE_SUBTREE:
520 case PTR_TYPE_INTERNAL:
521 continue;
522 default:
523 return fanout;
526 return fanout + 1;
529 /* hex SHA1 + 19 * '/' + NUL */
530 #define FANOUT_PATH_MAX GIT_SHA1_HEXSZ + FANOUT_PATH_SEPARATORS + 1
532 static void construct_path_with_fanout(const unsigned char *sha1,
533 unsigned char fanout, char *path)
535 unsigned int i = 0, j = 0;
536 const char *hex_sha1 = sha1_to_hex(sha1);
537 assert(fanout < GIT_SHA1_RAWSZ);
538 while (fanout) {
539 path[i++] = hex_sha1[j++];
540 path[i++] = hex_sha1[j++];
541 path[i++] = '/';
542 fanout--;
544 xsnprintf(path + i, FANOUT_PATH_MAX - i, "%s", hex_sha1 + j);
547 static int for_each_note_helper(struct notes_tree *t, struct int_node *tree,
548 unsigned char n, unsigned char fanout, int flags,
549 each_note_fn fn, void *cb_data)
551 unsigned int i;
552 void *p;
553 int ret = 0;
554 struct leaf_node *l;
555 static char path[FANOUT_PATH_MAX];
557 fanout = determine_fanout(tree, n, fanout);
558 for (i = 0; i < 16; i++) {
559 redo:
560 p = tree->a[i];
561 switch (GET_PTR_TYPE(p)) {
562 case PTR_TYPE_INTERNAL:
563 /* recurse into int_node */
564 ret = for_each_note_helper(t, CLR_PTR_TYPE(p), n + 1,
565 fanout, flags, fn, cb_data);
566 break;
567 case PTR_TYPE_SUBTREE:
568 l = (struct leaf_node *) CLR_PTR_TYPE(p);
570 * Subtree entries in the note tree represent parts of
571 * the note tree that have not yet been explored. There
572 * is a direct relationship between subtree entries at
573 * level 'n' in the tree, and the 'fanout' variable:
574 * Subtree entries at level 'n <= 2 * fanout' should be
575 * preserved, since they correspond exactly to a fanout
576 * directory in the on-disk structure. However, subtree
577 * entries at level 'n > 2 * fanout' should NOT be
578 * preserved, but rather consolidated into the above
579 * notes tree level. We achieve this by unconditionally
580 * unpacking subtree entries that exist below the
581 * threshold level at 'n = 2 * fanout'.
583 if (n <= 2 * fanout &&
584 flags & FOR_EACH_NOTE_YIELD_SUBTREES) {
585 /* invoke callback with subtree */
586 unsigned int path_len =
587 l->key_oid.hash[KEY_INDEX] * 2 + fanout;
588 assert(path_len < FANOUT_PATH_MAX - 1);
589 construct_path_with_fanout(l->key_oid.hash,
590 fanout,
591 path);
592 /* Create trailing slash, if needed */
593 if (path[path_len - 1] != '/')
594 path[path_len++] = '/';
595 path[path_len] = '\0';
596 ret = fn(&l->key_oid, &l->val_oid,
597 path,
598 cb_data);
600 if (n > fanout * 2 ||
601 !(flags & FOR_EACH_NOTE_DONT_UNPACK_SUBTREES)) {
602 /* unpack subtree and resume traversal */
603 tree->a[i] = NULL;
604 load_subtree(t, l, tree, n);
605 free(l);
606 goto redo;
608 break;
609 case PTR_TYPE_NOTE:
610 l = (struct leaf_node *) CLR_PTR_TYPE(p);
611 construct_path_with_fanout(l->key_oid.hash, fanout,
612 path);
613 ret = fn(&l->key_oid, &l->val_oid, path,
614 cb_data);
615 break;
617 if (ret)
618 return ret;
620 return 0;
623 struct tree_write_stack {
624 struct tree_write_stack *next;
625 struct strbuf buf;
626 char path[2]; /* path to subtree in next, if any */
629 static inline int matches_tree_write_stack(struct tree_write_stack *tws,
630 const char *full_path)
632 return full_path[0] == tws->path[0] &&
633 full_path[1] == tws->path[1] &&
634 full_path[2] == '/';
637 static void write_tree_entry(struct strbuf *buf, unsigned int mode,
638 const char *path, unsigned int path_len, const
639 unsigned char *sha1)
641 strbuf_addf(buf, "%o %.*s%c", mode, path_len, path, '\0');
642 strbuf_add(buf, sha1, GIT_SHA1_RAWSZ);
645 static void tree_write_stack_init_subtree(struct tree_write_stack *tws,
646 const char *path)
648 struct tree_write_stack *n;
649 assert(!tws->next);
650 assert(tws->path[0] == '\0' && tws->path[1] == '\0');
651 n = (struct tree_write_stack *)
652 xmalloc(sizeof(struct tree_write_stack));
653 n->next = NULL;
654 strbuf_init(&n->buf, 256 * (32 + GIT_SHA1_HEXSZ)); /* assume 256 entries per tree */
655 n->path[0] = n->path[1] = '\0';
656 tws->next = n;
657 tws->path[0] = path[0];
658 tws->path[1] = path[1];
661 static int tree_write_stack_finish_subtree(struct tree_write_stack *tws)
663 int ret;
664 struct tree_write_stack *n = tws->next;
665 struct object_id s;
666 if (n) {
667 ret = tree_write_stack_finish_subtree(n);
668 if (ret)
669 return ret;
670 ret = write_sha1_file(n->buf.buf, n->buf.len, tree_type, s.hash);
671 if (ret)
672 return ret;
673 strbuf_release(&n->buf);
674 free(n);
675 tws->next = NULL;
676 write_tree_entry(&tws->buf, 040000, tws->path, 2, s.hash);
677 tws->path[0] = tws->path[1] = '\0';
679 return 0;
682 static int write_each_note_helper(struct tree_write_stack *tws,
683 const char *path, unsigned int mode,
684 const struct object_id *oid)
686 size_t path_len = strlen(path);
687 unsigned int n = 0;
688 int ret;
690 /* Determine common part of tree write stack */
691 while (tws && 3 * n < path_len &&
692 matches_tree_write_stack(tws, path + 3 * n)) {
693 n++;
694 tws = tws->next;
697 /* tws point to last matching tree_write_stack entry */
698 ret = tree_write_stack_finish_subtree(tws);
699 if (ret)
700 return ret;
702 /* Start subtrees needed to satisfy path */
703 while (3 * n + 2 < path_len && path[3 * n + 2] == '/') {
704 tree_write_stack_init_subtree(tws, path + 3 * n);
705 n++;
706 tws = tws->next;
709 /* There should be no more directory components in the given path */
710 assert(memchr(path + 3 * n, '/', path_len - (3 * n)) == NULL);
712 /* Finally add given entry to the current tree object */
713 write_tree_entry(&tws->buf, mode, path + 3 * n, path_len - (3 * n),
714 oid->hash);
716 return 0;
719 struct write_each_note_data {
720 struct tree_write_stack *root;
721 struct non_note *next_non_note;
724 static int write_each_non_note_until(const char *note_path,
725 struct write_each_note_data *d)
727 struct non_note *n = d->next_non_note;
728 int cmp = 0, ret;
729 while (n && (!note_path || (cmp = strcmp(n->path, note_path)) <= 0)) {
730 if (note_path && cmp == 0)
731 ; /* do nothing, prefer note to non-note */
732 else {
733 ret = write_each_note_helper(d->root, n->path, n->mode,
734 &n->oid);
735 if (ret)
736 return ret;
738 n = n->next;
740 d->next_non_note = n;
741 return 0;
744 static int write_each_note(const struct object_id *object_oid,
745 const struct object_id *note_oid, char *note_path,
746 void *cb_data)
748 struct write_each_note_data *d =
749 (struct write_each_note_data *) cb_data;
750 size_t note_path_len = strlen(note_path);
751 unsigned int mode = 0100644;
753 if (note_path[note_path_len - 1] == '/') {
754 /* subtree entry */
755 note_path_len--;
756 note_path[note_path_len] = '\0';
757 mode = 040000;
759 assert(note_path_len <= GIT_SHA1_HEXSZ + FANOUT_PATH_SEPARATORS);
761 /* Weave non-note entries into note entries */
762 return write_each_non_note_until(note_path, d) ||
763 write_each_note_helper(d->root, note_path, mode, note_oid);
766 struct note_delete_list {
767 struct note_delete_list *next;
768 const unsigned char *sha1;
771 static int prune_notes_helper(const struct object_id *object_oid,
772 const struct object_id *note_oid, char *note_path,
773 void *cb_data)
775 struct note_delete_list **l = (struct note_delete_list **) cb_data;
776 struct note_delete_list *n;
778 if (has_object_file(object_oid))
779 return 0; /* nothing to do for this note */
781 /* failed to find object => prune this note */
782 n = (struct note_delete_list *) xmalloc(sizeof(*n));
783 n->next = *l;
784 n->sha1 = object_oid->hash;
785 *l = n;
786 return 0;
789 int combine_notes_concatenate(unsigned char *cur_sha1,
790 const unsigned char *new_sha1)
792 char *cur_msg = NULL, *new_msg = NULL, *buf;
793 unsigned long cur_len, new_len, buf_len;
794 enum object_type cur_type, new_type;
795 int ret;
797 /* read in both note blob objects */
798 if (!is_null_sha1(new_sha1))
799 new_msg = read_sha1_file(new_sha1, &new_type, &new_len);
800 if (!new_msg || !new_len || new_type != OBJ_BLOB) {
801 free(new_msg);
802 return 0;
804 if (!is_null_sha1(cur_sha1))
805 cur_msg = read_sha1_file(cur_sha1, &cur_type, &cur_len);
806 if (!cur_msg || !cur_len || cur_type != OBJ_BLOB) {
807 free(cur_msg);
808 free(new_msg);
809 hashcpy(cur_sha1, new_sha1);
810 return 0;
813 /* we will separate the notes by two newlines anyway */
814 if (cur_msg[cur_len - 1] == '\n')
815 cur_len--;
817 /* concatenate cur_msg and new_msg into buf */
818 buf_len = cur_len + 2 + new_len;
819 buf = (char *) xmalloc(buf_len);
820 memcpy(buf, cur_msg, cur_len);
821 buf[cur_len] = '\n';
822 buf[cur_len + 1] = '\n';
823 memcpy(buf + cur_len + 2, new_msg, new_len);
824 free(cur_msg);
825 free(new_msg);
827 /* create a new blob object from buf */
828 ret = write_sha1_file(buf, buf_len, blob_type, cur_sha1);
829 free(buf);
830 return ret;
833 int combine_notes_overwrite(unsigned char *cur_sha1,
834 const unsigned char *new_sha1)
836 hashcpy(cur_sha1, new_sha1);
837 return 0;
840 int combine_notes_ignore(unsigned char *cur_sha1,
841 const unsigned char *new_sha1)
843 return 0;
847 * Add the lines from the named object to list, with trailing
848 * newlines removed.
850 static int string_list_add_note_lines(struct string_list *list,
851 const unsigned char *sha1)
853 char *data;
854 unsigned long len;
855 enum object_type t;
857 if (is_null_sha1(sha1))
858 return 0;
860 /* read_sha1_file NUL-terminates */
861 data = read_sha1_file(sha1, &t, &len);
862 if (t != OBJ_BLOB || !data || !len) {
863 free(data);
864 return t != OBJ_BLOB || !data;
868 * If the last line of the file is EOL-terminated, this will
869 * add an empty string to the list. But it will be removed
870 * later, along with any empty strings that came from empty
871 * lines within the file.
873 string_list_split(list, data, '\n', -1);
874 free(data);
875 return 0;
878 static int string_list_join_lines_helper(struct string_list_item *item,
879 void *cb_data)
881 struct strbuf *buf = cb_data;
882 strbuf_addstr(buf, item->string);
883 strbuf_addch(buf, '\n');
884 return 0;
887 int combine_notes_cat_sort_uniq(unsigned char *cur_sha1,
888 const unsigned char *new_sha1)
890 struct string_list sort_uniq_list = STRING_LIST_INIT_DUP;
891 struct strbuf buf = STRBUF_INIT;
892 int ret = 1;
894 /* read both note blob objects into unique_lines */
895 if (string_list_add_note_lines(&sort_uniq_list, cur_sha1))
896 goto out;
897 if (string_list_add_note_lines(&sort_uniq_list, new_sha1))
898 goto out;
899 string_list_remove_empty_items(&sort_uniq_list, 0);
900 string_list_sort(&sort_uniq_list);
901 string_list_remove_duplicates(&sort_uniq_list, 0);
903 /* create a new blob object from sort_uniq_list */
904 if (for_each_string_list(&sort_uniq_list,
905 string_list_join_lines_helper, &buf))
906 goto out;
908 ret = write_sha1_file(buf.buf, buf.len, blob_type, cur_sha1);
910 out:
911 strbuf_release(&buf);
912 string_list_clear(&sort_uniq_list, 0);
913 return ret;
916 static int string_list_add_one_ref(const char *refname, const struct object_id *oid,
917 int flag, void *cb)
919 struct string_list *refs = cb;
920 if (!unsorted_string_list_has_string(refs, refname))
921 string_list_append(refs, refname);
922 return 0;
926 * The list argument must have strdup_strings set on it.
928 void string_list_add_refs_by_glob(struct string_list *list, const char *glob)
930 assert(list->strdup_strings);
931 if (has_glob_specials(glob)) {
932 for_each_glob_ref(string_list_add_one_ref, glob, list);
933 } else {
934 struct object_id oid;
935 if (get_oid(glob, &oid))
936 warning("notes ref %s is invalid", glob);
937 if (!unsorted_string_list_has_string(list, glob))
938 string_list_append(list, glob);
942 void string_list_add_refs_from_colon_sep(struct string_list *list,
943 const char *globs)
945 struct string_list split = STRING_LIST_INIT_NODUP;
946 char *globs_copy = xstrdup(globs);
947 int i;
949 string_list_split_in_place(&split, globs_copy, ':', -1);
950 string_list_remove_empty_items(&split, 0);
952 for (i = 0; i < split.nr; i++)
953 string_list_add_refs_by_glob(list, split.items[i].string);
955 string_list_clear(&split, 0);
956 free(globs_copy);
959 static int notes_display_config(const char *k, const char *v, void *cb)
961 int *load_refs = cb;
963 if (*load_refs && !strcmp(k, "notes.displayref")) {
964 if (!v)
965 config_error_nonbool(k);
966 string_list_add_refs_by_glob(&display_notes_refs, v);
969 return 0;
972 const char *default_notes_ref(void)
974 const char *notes_ref = NULL;
975 if (!notes_ref)
976 notes_ref = getenv(GIT_NOTES_REF_ENVIRONMENT);
977 if (!notes_ref)
978 notes_ref = notes_ref_name; /* value of core.notesRef config */
979 if (!notes_ref)
980 notes_ref = GIT_NOTES_DEFAULT_REF;
981 return notes_ref;
984 void init_notes(struct notes_tree *t, const char *notes_ref,
985 combine_notes_fn combine_notes, int flags)
987 struct object_id oid, object_oid;
988 unsigned mode;
989 struct leaf_node root_tree;
991 if (!t)
992 t = &default_notes_tree;
993 assert(!t->initialized);
995 if (!notes_ref)
996 notes_ref = default_notes_ref();
998 if (!combine_notes)
999 combine_notes = combine_notes_concatenate;
1001 t->root = (struct int_node *) xcalloc(1, sizeof(struct int_node));
1002 t->first_non_note = NULL;
1003 t->prev_non_note = NULL;
1004 t->ref = xstrdup_or_null(notes_ref);
1005 t->update_ref = (flags & NOTES_INIT_WRITABLE) ? t->ref : NULL;
1006 t->combine_notes = combine_notes;
1007 t->initialized = 1;
1008 t->dirty = 0;
1010 if (flags & NOTES_INIT_EMPTY || !notes_ref ||
1011 get_oid_treeish(notes_ref, &object_oid))
1012 return;
1013 if (flags & NOTES_INIT_WRITABLE && read_ref(notes_ref, &object_oid))
1014 die("Cannot use notes ref %s", notes_ref);
1015 if (get_tree_entry(object_oid.hash, "", oid.hash, &mode))
1016 die("Failed to read notes tree referenced by %s (%s)",
1017 notes_ref, oid_to_hex(&object_oid));
1019 oidclr(&root_tree.key_oid);
1020 oidcpy(&root_tree.val_oid, &oid);
1021 load_subtree(t, &root_tree, t->root, 0);
1024 struct notes_tree **load_notes_trees(struct string_list *refs, int flags)
1026 struct string_list_item *item;
1027 int counter = 0;
1028 struct notes_tree **trees;
1029 ALLOC_ARRAY(trees, refs->nr + 1);
1030 for_each_string_list_item(item, refs) {
1031 struct notes_tree *t = xcalloc(1, sizeof(struct notes_tree));
1032 init_notes(t, item->string, combine_notes_ignore, flags);
1033 trees[counter++] = t;
1035 trees[counter] = NULL;
1036 return trees;
1039 void init_display_notes(struct display_notes_opt *opt)
1041 char *display_ref_env;
1042 int load_config_refs = 0;
1043 display_notes_refs.strdup_strings = 1;
1045 assert(!display_notes_trees);
1047 if (!opt || opt->use_default_notes > 0 ||
1048 (opt->use_default_notes == -1 && !opt->extra_notes_refs.nr)) {
1049 string_list_append(&display_notes_refs, default_notes_ref());
1050 display_ref_env = getenv(GIT_NOTES_DISPLAY_REF_ENVIRONMENT);
1051 if (display_ref_env) {
1052 string_list_add_refs_from_colon_sep(&display_notes_refs,
1053 display_ref_env);
1054 load_config_refs = 0;
1055 } else
1056 load_config_refs = 1;
1059 git_config(notes_display_config, &load_config_refs);
1061 if (opt) {
1062 struct string_list_item *item;
1063 for_each_string_list_item(item, &opt->extra_notes_refs)
1064 string_list_add_refs_by_glob(&display_notes_refs,
1065 item->string);
1068 display_notes_trees = load_notes_trees(&display_notes_refs, 0);
1069 string_list_clear(&display_notes_refs, 0);
1072 int add_note(struct notes_tree *t, const struct object_id *object_oid,
1073 const struct object_id *note_oid, combine_notes_fn combine_notes)
1075 struct leaf_node *l;
1077 if (!t)
1078 t = &default_notes_tree;
1079 assert(t->initialized);
1080 t->dirty = 1;
1081 if (!combine_notes)
1082 combine_notes = t->combine_notes;
1083 l = (struct leaf_node *) xmalloc(sizeof(struct leaf_node));
1084 oidcpy(&l->key_oid, object_oid);
1085 oidcpy(&l->val_oid, note_oid);
1086 return note_tree_insert(t, t->root, 0, l, PTR_TYPE_NOTE, combine_notes);
1089 int remove_note(struct notes_tree *t, const unsigned char *object_sha1)
1091 struct leaf_node l;
1093 if (!t)
1094 t = &default_notes_tree;
1095 assert(t->initialized);
1096 hashcpy(l.key_oid.hash, object_sha1);
1097 oidclr(&l.val_oid);
1098 note_tree_remove(t, t->root, 0, &l);
1099 if (is_null_oid(&l.val_oid)) /* no note was removed */
1100 return 1;
1101 t->dirty = 1;
1102 return 0;
1105 const struct object_id *get_note(struct notes_tree *t,
1106 const struct object_id *oid)
1108 struct leaf_node *found;
1110 if (!t)
1111 t = &default_notes_tree;
1112 assert(t->initialized);
1113 found = note_tree_find(t, t->root, 0, oid->hash);
1114 return found ? &found->val_oid : NULL;
1117 int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
1118 void *cb_data)
1120 if (!t)
1121 t = &default_notes_tree;
1122 assert(t->initialized);
1123 return for_each_note_helper(t, t->root, 0, 0, flags, fn, cb_data);
1126 int write_notes_tree(struct notes_tree *t, unsigned char *result)
1128 struct tree_write_stack root;
1129 struct write_each_note_data cb_data;
1130 int ret;
1132 if (!t)
1133 t = &default_notes_tree;
1134 assert(t->initialized);
1136 /* Prepare for traversal of current notes tree */
1137 root.next = NULL; /* last forward entry in list is grounded */
1138 strbuf_init(&root.buf, 256 * (32 + GIT_SHA1_HEXSZ)); /* assume 256 entries */
1139 root.path[0] = root.path[1] = '\0';
1140 cb_data.root = &root;
1141 cb_data.next_non_note = t->first_non_note;
1143 /* Write tree objects representing current notes tree */
1144 ret = for_each_note(t, FOR_EACH_NOTE_DONT_UNPACK_SUBTREES |
1145 FOR_EACH_NOTE_YIELD_SUBTREES,
1146 write_each_note, &cb_data) ||
1147 write_each_non_note_until(NULL, &cb_data) ||
1148 tree_write_stack_finish_subtree(&root) ||
1149 write_sha1_file(root.buf.buf, root.buf.len, tree_type, result);
1150 strbuf_release(&root.buf);
1151 return ret;
1154 void prune_notes(struct notes_tree *t, int flags)
1156 struct note_delete_list *l = NULL;
1158 if (!t)
1159 t = &default_notes_tree;
1160 assert(t->initialized);
1162 for_each_note(t, 0, prune_notes_helper, &l);
1164 while (l) {
1165 if (flags & NOTES_PRUNE_VERBOSE)
1166 printf("%s\n", sha1_to_hex(l->sha1));
1167 if (!(flags & NOTES_PRUNE_DRYRUN))
1168 remove_note(t, l->sha1);
1169 l = l->next;
1173 void free_notes(struct notes_tree *t)
1175 if (!t)
1176 t = &default_notes_tree;
1177 if (t->root)
1178 note_tree_free(t->root);
1179 free(t->root);
1180 while (t->first_non_note) {
1181 t->prev_non_note = t->first_non_note->next;
1182 free(t->first_non_note->path);
1183 free(t->first_non_note);
1184 t->first_non_note = t->prev_non_note;
1186 free(t->ref);
1187 memset(t, 0, sizeof(struct notes_tree));
1191 * Fill the given strbuf with the notes associated with the given object.
1193 * If the given notes_tree structure is not initialized, it will be auto-
1194 * initialized to the default value (see documentation for init_notes() above).
1195 * If the given notes_tree is NULL, the internal/default notes_tree will be
1196 * used instead.
1198 * (raw != 0) gives the %N userformat; otherwise, the note message is given
1199 * for human consumption.
1201 static void format_note(struct notes_tree *t, const struct object_id *object_oid,
1202 struct strbuf *sb, const char *output_encoding, int raw)
1204 static const char utf8[] = "utf-8";
1205 const struct object_id *oid;
1206 char *msg, *msg_p;
1207 unsigned long linelen, msglen;
1208 enum object_type type;
1210 if (!t)
1211 t = &default_notes_tree;
1212 if (!t->initialized)
1213 init_notes(t, NULL, NULL, 0);
1215 oid = get_note(t, object_oid);
1216 if (!oid)
1217 return;
1219 if (!(msg = read_sha1_file(oid->hash, &type, &msglen)) || type != OBJ_BLOB) {
1220 free(msg);
1221 return;
1224 if (output_encoding && *output_encoding &&
1225 !is_encoding_utf8(output_encoding)) {
1226 char *reencoded = reencode_string(msg, output_encoding, utf8);
1227 if (reencoded) {
1228 free(msg);
1229 msg = reencoded;
1230 msglen = strlen(msg);
1234 /* we will end the annotation by a newline anyway */
1235 if (msglen && msg[msglen - 1] == '\n')
1236 msglen--;
1238 if (!raw) {
1239 const char *ref = t->ref;
1240 if (!ref || !strcmp(ref, GIT_NOTES_DEFAULT_REF)) {
1241 strbuf_addstr(sb, "\nNotes:\n");
1242 } else {
1243 if (starts_with(ref, "refs/"))
1244 ref += 5;
1245 if (starts_with(ref, "notes/"))
1246 ref += 6;
1247 strbuf_addf(sb, "\nNotes (%s):\n", ref);
1251 for (msg_p = msg; msg_p < msg + msglen; msg_p += linelen + 1) {
1252 linelen = strchrnul(msg_p, '\n') - msg_p;
1254 if (!raw)
1255 strbuf_addstr(sb, " ");
1256 strbuf_add(sb, msg_p, linelen);
1257 strbuf_addch(sb, '\n');
1260 free(msg);
1263 void format_display_notes(const struct object_id *object_oid,
1264 struct strbuf *sb, const char *output_encoding, int raw)
1266 int i;
1267 assert(display_notes_trees);
1268 for (i = 0; display_notes_trees[i]; i++)
1269 format_note(display_notes_trees[i], object_oid, sb,
1270 output_encoding, raw);
1273 int copy_note(struct notes_tree *t,
1274 const struct object_id *from_obj, const struct object_id *to_obj,
1275 int force, combine_notes_fn combine_notes)
1277 const struct object_id *note = get_note(t, from_obj);
1278 const struct object_id *existing_note = get_note(t, to_obj);
1280 if (!force && existing_note)
1281 return 1;
1283 if (note)
1284 return add_note(t, to_obj, note, combine_notes);
1285 else if (existing_note)
1286 return add_note(t, to_obj, &null_oid, combine_notes);
1288 return 0;
1291 void expand_notes_ref(struct strbuf *sb)
1293 if (starts_with(sb->buf, "refs/notes/"))
1294 return; /* we're happy */
1295 else if (starts_with(sb->buf, "notes/"))
1296 strbuf_insert(sb, 0, "refs/", 5);
1297 else
1298 strbuf_insert(sb, 0, "refs/notes/", 11);
1301 void expand_loose_notes_ref(struct strbuf *sb)
1303 struct object_id object;
1305 if (get_oid(sb->buf, &object)) {
1306 /* fallback to expand_notes_ref */
1307 expand_notes_ref(sb);