blob: 3f48a2aac33225e7b5075011d2cb69489d0e1498 [file] [log] [blame]
#include "cache.h"
#include "config.h"
#include "notes.h"
#include "object-store.h"
#include "blob.h"
#include "tree.h"
#include "utf8.h"
#include "strbuf.h"
#include "tree-walk.h"
#include "string-list.h"
#include "refs.h"
/*
* Use a non-balancing simple 16-tree structure with struct int_node as
* internal nodes, and struct leaf_node as leaf nodes. Each int_node has a
* 16-array of pointers to its children.
* The bottom 2 bits of each pointer is used to identify the pointer type
* - ptr & 3 == 0 - NULL pointer, assert(ptr == NULL)
* - ptr & 3 == 1 - pointer to next internal node - cast to struct int_node *
* - ptr & 3 == 2 - pointer to note entry - cast to struct leaf_node *
* - ptr & 3 == 3 - pointer to subtree entry - cast to struct leaf_node *
*
* The root node is a statically allocated struct int_node.
*/
struct int_node {
void *a[16];
};
/*
* Leaf nodes come in two variants, note entries and subtree entries,
* distinguished by the LSb of the leaf node pointer (see above).
* As a note entry, the key is the SHA1 of the referenced object, and the
* value is the SHA1 of the note object.
* As a subtree entry, the key is the prefix SHA1 (w/trailing NULs) of the
* referenced object, using the last byte of the key to store the length of
* the prefix. The value is the SHA1 of the tree object containing the notes
* subtree.
*/
struct leaf_node {
struct object_id key_oid;
struct object_id val_oid;
};
/*
* A notes tree may contain entries that are not notes, and that do not follow
* the naming conventions of notes. There are typically none/few of these, but
* we still need to keep track of them. Keep a simple linked list sorted alpha-
* betically on the non-note path. The list is populated when parsing tree
* objects in load_subtree(), and the non-notes are correctly written back into
* the tree objects produced by write_notes_tree().
*/
struct non_note {
struct non_note *next; /* grounded (last->next == NULL) */
char *path;
unsigned int mode;
struct object_id oid;
};
#define PTR_TYPE_NULL 0
#define PTR_TYPE_INTERNAL 1
#define PTR_TYPE_NOTE 2
#define PTR_TYPE_SUBTREE 3
#define GET_PTR_TYPE(ptr) ((uintptr_t) (ptr) & 3)
#define CLR_PTR_TYPE(ptr) ((void *) ((uintptr_t) (ptr) & ~3))
#define SET_PTR_TYPE(ptr, type) ((void *) ((uintptr_t) (ptr) | (type)))
#define GET_NIBBLE(n, sha1) ((((sha1)[(n) >> 1]) >> ((~(n) & 0x01) << 2)) & 0x0f)
#define KEY_INDEX (the_hash_algo->rawsz - 1)
#define FANOUT_PATH_SEPARATORS (the_hash_algo->rawsz - 1)
#define FANOUT_PATH_SEPARATORS_MAX ((GIT_MAX_HEXSZ / 2) - 1)
#define SUBTREE_SHA1_PREFIXCMP(key_sha1, subtree_sha1) \
(memcmp(key_sha1, subtree_sha1, subtree_sha1[KEY_INDEX]))
struct notes_tree default_notes_tree;
static struct string_list display_notes_refs = STRING_LIST_INIT_NODUP;
static struct notes_tree **display_notes_trees;
static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
struct int_node *node, unsigned int n);
/*
* Search the tree until the appropriate location for the given key is found:
* 1. Start at the root node, with n = 0
* 2. If a[0] at the current level is a matching subtree entry, unpack that
* subtree entry and remove it; restart search at the current level.
* 3. Use the nth nibble of the key as an index into a:
* - If a[n] is an int_node, recurse from #2 into that node and increment n
* - If a matching subtree entry, unpack that subtree entry (and remove it);
* restart search at the current level.
* - Otherwise, we have found one of the following:
* - a subtree entry which does not match the key
* - a note entry which may or may not match the key
* - an unused leaf node (NULL)
* In any case, set *tree and *n, and return pointer to the tree location.
*/
static void **note_tree_search(struct notes_tree *t, struct int_node **tree,
unsigned char *n, const unsigned char *key_sha1)
{
struct leaf_node *l;
unsigned char i;
void *p = (*tree)->a[0];
if (GET_PTR_TYPE(p) == PTR_TYPE_SUBTREE) {
l = (struct leaf_node *) CLR_PTR_TYPE(p);
if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
/* unpack tree and resume search */
(*tree)->a[0] = NULL;
load_subtree(t, l, *tree, *n);
free(l);
return note_tree_search(t, tree, n, key_sha1);
}
}
i = GET_NIBBLE(*n, key_sha1);
p = (*tree)->a[i];
switch (GET_PTR_TYPE(p)) {
case PTR_TYPE_INTERNAL:
*tree = CLR_PTR_TYPE(p);
(*n)++;
return note_tree_search(t, tree, n, key_sha1);
case PTR_TYPE_SUBTREE:
l = (struct leaf_node *) CLR_PTR_TYPE(p);
if (!SUBTREE_SHA1_PREFIXCMP(key_sha1, l->key_oid.hash)) {
/* unpack tree and resume search */
(*tree)->a[i] = NULL;
load_subtree(t, l, *tree, *n);
free(l);
return note_tree_search(t, tree, n, key_sha1);
}
/* fall through */
default:
return &((*tree)->a[i]);
}
}
/*
* To find a leaf_node:
* Search to the tree location appropriate for the given key:
* If a note entry with matching key, return the note entry, else return NULL.
*/
static struct leaf_node *note_tree_find(struct notes_tree *t,
struct int_node *tree, unsigned char n,
const unsigned char *key_sha1)
{
void **p = note_tree_search(t, &tree, &n, key_sha1);
if (GET_PTR_TYPE(*p) == PTR_TYPE_NOTE) {
struct leaf_node *l = (struct leaf_node *) CLR_PTR_TYPE(*p);
if (hasheq(key_sha1, l->key_oid.hash))
return l;
}
return NULL;
}
/*
* How to consolidate an int_node:
* If there are > 1 non-NULL entries, give up and return non-zero.
* Otherwise replace the int_node at the given index in the given parent node
* with the only NOTE entry (or a NULL entry if no entries) from the given
* tree, and return 0.
*/
static int note_tree_consolidate(struct int_node *tree,
struct int_node *parent, unsigned char index)
{
unsigned int i;
void *p = NULL;
assert(tree && parent);
assert(CLR_PTR_TYPE(parent->a[index]) == tree);
for (i = 0; i < 16; i++) {
if (GET_PTR_TYPE(tree->a[i]) != PTR_TYPE_NULL) {
if (p) /* more than one entry */
return -2;
p = tree->a[i];
}
}
if (p && (GET_PTR_TYPE(p) != PTR_TYPE_NOTE))
return -2;
/* replace tree with p in parent[index] */
parent->a[index] = p;
free(tree);
return 0;
}
/*
* To remove a leaf_node:
* Search to the tree location appropriate for the given leaf_node's key:
* - If location does not hold a matching entry, abort and do nothing.
* - Copy the matching entry's value into the given entry.
* - Replace the matching leaf_node with a NULL entry (and free the leaf_node).
* - Consolidate int_nodes repeatedly, while walking up the tree towards root.
*/
static void note_tree_remove(struct notes_tree *t,
struct int_node *tree, unsigned char n,
struct leaf_node *entry)
{
struct leaf_node *l;
struct int_node *parent_stack[GIT_MAX_RAWSZ];
unsigned char i, j;
void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
if (GET_PTR_TYPE(*p) != PTR_TYPE_NOTE)
return; /* type mismatch, nothing to remove */
l = (struct leaf_node *) CLR_PTR_TYPE(*p);
if (!oideq(&l->key_oid, &entry->key_oid))
return; /* key mismatch, nothing to remove */
/* we have found a matching entry */
oidcpy(&entry->val_oid, &l->val_oid);
free(l);
*p = SET_PTR_TYPE(NULL, PTR_TYPE_NULL);
/* consolidate this tree level, and parent levels, if possible */
if (!n)
return; /* cannot consolidate top level */
/* first, build stack of ancestors between root and current node */
parent_stack[0] = t->root;
for (i = 0; i < n; i++) {
j = GET_NIBBLE(i, entry->key_oid.hash);
parent_stack[i + 1] = CLR_PTR_TYPE(parent_stack[i]->a[j]);
}
assert(i == n && parent_stack[i] == tree);
/* next, unwind stack until note_tree_consolidate() is done */
while (i > 0 &&
!note_tree_consolidate(parent_stack[i], parent_stack[i - 1],
GET_NIBBLE(i - 1, entry->key_oid.hash)))
i--;
}
/*
* To insert a leaf_node:
* Search to the tree location appropriate for the given leaf_node's key:
* - If location is unused (NULL), store the tweaked pointer directly there
* - If location holds a note entry that matches the note-to-be-inserted, then
* combine the two notes (by calling the given combine_notes function).
* - If location holds a note entry that matches the subtree-to-be-inserted,
* then unpack the subtree-to-be-inserted into the location.
* - If location holds a matching subtree entry, unpack the subtree at that
* location, and restart the insert operation from that level.
* - Else, create a new int_node, holding both the node-at-location and the
* node-to-be-inserted, and store the new int_node into the location.
*/
static int note_tree_insert(struct notes_tree *t, struct int_node *tree,
unsigned char n, struct leaf_node *entry, unsigned char type,
combine_notes_fn combine_notes)
{
struct int_node *new_node;
struct leaf_node *l;
void **p = note_tree_search(t, &tree, &n, entry->key_oid.hash);
int ret = 0;
assert(GET_PTR_TYPE(entry) == 0); /* no type bits set */
l = (struct leaf_node *) CLR_PTR_TYPE(*p);
switch (GET_PTR_TYPE(*p)) {
case PTR_TYPE_NULL:
assert(!*p);
if (is_null_oid(&entry->val_oid))
free(entry);
else
*p = SET_PTR_TYPE(entry, type);
return 0;
case PTR_TYPE_NOTE:
switch (type) {
case PTR_TYPE_NOTE:
if (oideq(&l->key_oid, &entry->key_oid)) {
/* skip concatenation if l == entry */
if (oideq(&l->val_oid, &entry->val_oid)) {
free(entry);
return 0;
}
ret = combine_notes(&l->val_oid,
&entry->val_oid);
if (!ret && is_null_oid(&l->val_oid))
note_tree_remove(t, tree, n, entry);
free(entry);
return ret;
}
break;
case PTR_TYPE_SUBTREE:
if (!SUBTREE_SHA1_PREFIXCMP(l->key_oid.hash,
entry->key_oid.hash)) {
/* unpack 'entry' */
load_subtree(t, entry, tree, n);
free(entry);
return 0;
}
break;
}
break;
case PTR_TYPE_SUBTREE:
if (!SUBTREE_SHA1_PREFIXCMP(entry->key_oid.hash, l->key_oid.hash)) {
/* unpack 'l' and restart insert */
*p = NULL;
load_subtree(t, l, tree, n);
free(l);
return note_tree_insert(t, tree, n, entry, type,
combine_notes);
}
break;
}
/* non-matching leaf_node */
assert(GET_PTR_TYPE(*p) == PTR_TYPE_NOTE ||
GET_PTR_TYPE(*p) == PTR_TYPE_SUBTREE);
if (is_null_oid(&entry->val_oid)) { /* skip insertion of empty note */
free(entry);
return 0;
}
new_node = (struct int_node *) xcalloc(1, sizeof(struct int_node));
ret = note_tree_insert(t, new_node, n + 1, l, GET_PTR_TYPE(*p),
combine_notes);
if (ret)
return ret;
*p = SET_PTR_TYPE(new_node, PTR_TYPE_INTERNAL);
return note_tree_insert(t, new_node, n + 1, entry, type, combine_notes);
}
/* Free the entire notes data contained in the given tree */
static void note_tree_free(struct int_node *tree)
{
unsigned int i;
for (i = 0; i < 16; i++) {
void *p = tree->a[i];
switch (GET_PTR_TYPE(p)) {
case PTR_TYPE_INTERNAL:
note_tree_free(CLR_PTR_TYPE(p));
/* fall through */
case PTR_TYPE_NOTE:
case PTR_TYPE_SUBTREE:
free(CLR_PTR_TYPE(p));
}
}
}
static int non_note_cmp(const struct non_note *a, const struct non_note *b)
{
return strcmp(a->path, b->path);
}
/* note: takes ownership of path string */
static void add_non_note(struct notes_tree *t, char *path,
unsigned int mode, const unsigned char *sha1)
{
struct non_note *p = t->prev_non_note, *n;
n = (struct non_note *) xmalloc(sizeof(struct non_note));
n->next = NULL;
n->path = path;
n->mode = mode;
oidread(&n->oid, sha1);
t->prev_non_note = n;
if (!t->first_non_note) {
t->first_non_note = n;
return;
}
if (non_note_cmp(p, n) < 0)
; /* do nothing */
else if (non_note_cmp(t->first_non_note, n) <= 0)
p = t->first_non_note;
else {
/* n sorts before t->first_non_note */
n->next = t->first_non_note;
t->first_non_note = n;
return;
}
/* n sorts equal or after p */
while (p->next && non_note_cmp(p->next, n) <= 0)
p = p->next;
if (non_note_cmp(p, n) == 0) { /* n ~= p; overwrite p with n */
assert(strcmp(p->path, n->path) == 0);
p->mode = n->mode;
oidcpy(&p->oid, &n->oid);
free(n);
t->prev_non_note = p;
return;
}
/* n sorts between p and p->next */
n->next = p->next;
p->next = n;
}
static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
struct int_node *node, unsigned int n)
{
struct object_id object_oid;
size_t prefix_len;
void *buf;
struct tree_desc desc;
struct name_entry entry;
const unsigned hashsz = the_hash_algo->rawsz;
buf = fill_tree_descriptor(the_repository, &desc, &subtree->val_oid);
if (!buf)
die("Could not read %s for notes-index",
oid_to_hex(&subtree->val_oid));
prefix_len = subtree->key_oid.hash[KEY_INDEX];
if (prefix_len >= hashsz)
BUG("prefix_len (%"PRIuMAX") is out of range", (uintmax_t)prefix_len);
if (prefix_len * 2 < n)
BUG("prefix_len (%"PRIuMAX") is too small", (uintmax_t)prefix_len);
memcpy(object_oid.hash, subtree->key_oid.hash, prefix_len);
while (tree_entry(&desc, &entry)) {
unsigned char type;
struct leaf_node *l;
size_t path_len = strlen(entry.path);
if (path_len == 2 * (hashsz - prefix_len)) {
/* This is potentially the remainder of the SHA-1 */
if (!S_ISREG(entry.mode))
/* notes must be blobs */
goto handle_non_note;
if (hex_to_bytes(object_oid.hash + prefix_len, entry.path,
hashsz - prefix_len))
goto handle_non_note; /* entry.path is not a SHA1 */
type = PTR_TYPE_NOTE;
} else if (path_len == 2) {
/* This is potentially an internal node */
size_t len = prefix_len;
if (!S_ISDIR(entry.mode))
/* internal nodes must be trees */
goto handle_non_note;
if (hex_to_bytes(object_oid.hash + len++, entry.path, 1))
goto handle_non_note; /* entry.path is not a SHA1 */
/*
* Pad the rest of the SHA-1 with zeros,
* except for the last byte, where we write
* the length:
*/
memset(object_oid.hash + len, 0, hashsz - len - 1);
object_oid.hash[KEY_INDEX] = (unsigned char)len;
type = PTR_TYPE_SUBTREE;
} else {
/* This can't be part of a note */
goto handle_non_note;
}
CALLOC_ARRAY(l, 1);
oidcpy(&l->key_oid, &object_oid);
oidcpy(&l->val_oid, &entry.oid);
oid_pad_buffer(&l->key_oid, the_hash_algo);
oid_pad_buffer(&l->val_oid, the_hash_algo);
if (note_tree_insert(t, node, n, l, type,
combine_notes_concatenate))
die("Failed to load %s %s into notes tree "
"from %s",
type == PTR_TYPE_NOTE ? "note" : "subtree",
oid_to_hex(&object_oid), t->ref);
continue;
handle_non_note:
/*
* Determine full path for this non-note entry. The
* filename is already found in entry.path, but the
* directory part of the path must be deduced from the
* subtree containing this entry based on our
* knowledge that the overall notes tree follows a
* strict byte-based progressive fanout structure
* (i.e. using 2/38, 2/2/36, etc. fanouts).
*/
{
struct strbuf non_note_path = STRBUF_INIT;
const char *q = oid_to_hex(&subtree->key_oid);
size_t i;
for (i = 0; i < prefix_len; i++) {
strbuf_addch(&non_note_path, *q++);
strbuf_addch(&non_note_path, *q++);
strbuf_addch(&non_note_path, '/');
}
strbuf_addstr(&non_note_path, entry.path);
oid_pad_buffer(&entry.oid, the_hash_algo);
add_non_note(t, strbuf_detach(&non_note_path, NULL),
entry.mode, entry.oid.hash);
}
}
free(buf);
}
/*
* Determine optimal on-disk fanout for this part of the notes tree
*
* Given a (sub)tree and the level in the internal tree structure, determine
* whether or not the given existing fanout should be expanded for this
* (sub)tree.
*
* Values of the 'fanout' variable:
* - 0: No fanout (all notes are stored directly in the root notes tree)
* - 1: 2/38 fanout
* - 2: 2/2/36 fanout
* - 3: 2/2/2/34 fanout
* etc.
*/
static unsigned char determine_fanout(struct int_node *tree, unsigned char n,
unsigned char fanout)
{
/*
* The following is a simple heuristic that works well in practice:
* For each even-numbered 16-tree level (remember that each on-disk
* fanout level corresponds to _two_ 16-tree levels), peek at all 16
* entries at that tree level. If all of them are either int_nodes or
* subtree entries, then there are likely plenty of notes below this
* level, so we return an incremented fanout.
*/
unsigned int i;
if ((n % 2) || (n > 2 * fanout))
return fanout;
for (i = 0; i < 16; i++) {
switch (GET_PTR_TYPE(tree->a[i])) {
case PTR_TYPE_SUBTREE:
case PTR_TYPE_INTERNAL:
continue;
default:
return fanout;
}
}
return fanout + 1;
}
/* hex oid + '/' between each pair of hex digits + NUL */
#define FANOUT_PATH_MAX GIT_MAX_HEXSZ + FANOUT_PATH_SEPARATORS_MAX + 1
static void construct_path_with_fanout(const unsigned char *hash,
unsigned char fanout, char *path)
{
unsigned int i = 0, j = 0;
const char *hex_hash = hash_to_hex(hash);
assert(fanout < the_hash_algo->rawsz);
while (fanout) {
path[i++] = hex_hash[j++];
path[i++] = hex_hash[j++];
path[i++] = '/';
fanout--;
}
xsnprintf(path + i, FANOUT_PATH_MAX - i, "%s", hex_hash + j);
}
static int for_each_note_helper(struct notes_tree *t, struct int_node *tree,
unsigned char n, unsigned char fanout, int flags,
each_note_fn fn, void *cb_data)
{
unsigned int i;
void *p;
int ret = 0;
struct leaf_node *l;
static char path[FANOUT_PATH_MAX];
fanout = determine_fanout(tree, n, fanout);
for (i = 0; i < 16; i++) {
redo:
p = tree->a[i];
switch (GET_PTR_TYPE(p)) {
case PTR_TYPE_INTERNAL:
/* recurse into int_node */
ret = for_each_note_helper(t, CLR_PTR_TYPE(p), n + 1,
fanout, flags, fn, cb_data);
break;
case PTR_TYPE_SUBTREE:
l = (struct leaf_node *) CLR_PTR_TYPE(p);
/*
* Subtree entries in the note tree represent parts of
* the note tree that have not yet been explored. There
* is a direct relationship between subtree entries at
* level 'n' in the tree, and the 'fanout' variable:
* Subtree entries at level 'n < 2 * fanout' should be
* preserved, since they correspond exactly to a fanout
* directory in the on-disk structure. However, subtree
* entries at level 'n >= 2 * fanout' should NOT be
* preserved, but rather consolidated into the above
* notes tree level. We achieve this by unconditionally
* unpacking subtree entries that exist below the
* threshold level at 'n = 2 * fanout'.
*/
if (n < 2 * fanout &&
flags & FOR_EACH_NOTE_YIELD_SUBTREES) {
/* invoke callback with subtree */
unsigned int path_len =
l->key_oid.hash[KEY_INDEX] * 2 + fanout;
assert(path_len < FANOUT_PATH_MAX - 1);
construct_path_with_fanout(l->key_oid.hash,
fanout,
path);
/* Create trailing slash, if needed */
if (path[path_len - 1] != '/')
path[path_len++] = '/';
path[path_len] = '\0';
ret = fn(&l->key_oid, &l->val_oid,
path,
cb_data);
}
if (n >= 2 * fanout ||
!(flags & FOR_EACH_NOTE_DONT_UNPACK_SUBTREES)) {
/* unpack subtree and resume traversal */
tree->a[i] = NULL;
load_subtree(t, l, tree, n);
free(l);
goto redo;
}
break;
case PTR_TYPE_NOTE:
l = (struct leaf_node *) CLR_PTR_TYPE(p);
construct_path_with_fanout(l->key_oid.hash, fanout,
path);
ret = fn(&l->key_oid, &l->val_oid, path,
cb_data);
break;
}
if (ret)
return ret;
}
return 0;
}
struct tree_write_stack {
struct tree_write_stack *next;
struct strbuf buf;
char path[2]; /* path to subtree in next, if any */
};
static inline int matches_tree_write_stack(struct tree_write_stack *tws,
const char *full_path)
{
return full_path[0] == tws->path[0] &&
full_path[1] == tws->path[1] &&
full_path[2] == '/';
}
static void write_tree_entry(struct strbuf *buf, unsigned int mode,
const char *path, unsigned int path_len, const
unsigned char *hash)
{
strbuf_addf(buf, "%o %.*s%c", mode, path_len, path, '\0');
strbuf_add(buf, hash, the_hash_algo->rawsz);
}
static void tree_write_stack_init_subtree(struct tree_write_stack *tws,
const char *path)
{
struct tree_write_stack *n;
assert(!tws->next);
assert(tws->path[0] == '\0' && tws->path[1] == '\0');
n = (struct tree_write_stack *)
xmalloc(sizeof(struct tree_write_stack));
n->next = NULL;
strbuf_init(&n->buf, 256 * (32 + the_hash_algo->hexsz)); /* assume 256 entries per tree */
n->path[0] = n->path[1] = '\0';
tws->next = n;
tws->path[0] = path[0];
tws->path[1] = path[1];
}
static int tree_write_stack_finish_subtree(struct tree_write_stack *tws)
{
int ret;
struct tree_write_stack *n = tws->next;
struct object_id s;
if (n) {
ret = tree_write_stack_finish_subtree(n);
if (ret)
return ret;
ret = write_object_file(n->buf.buf, n->buf.len, tree_type, &s);
if (ret)
return ret;
strbuf_release(&n->buf);
free(n);
tws->next = NULL;
write_tree_entry(&tws->buf, 040000, tws->path, 2, s.hash);
tws->path[0] = tws->path[1] = '\0';
}
return 0;
}
static int write_each_note_helper(struct tree_write_stack *tws,
const char *path, unsigned int mode,
const struct object_id *oid)
{
size_t path_len = strlen(path);
unsigned int n = 0;
int ret;
/* Determine common part of tree write stack */
while (tws && 3 * n < path_len &&
matches_tree_write_stack(tws, path + 3 * n)) {
n++;
tws = tws->next;
}
/* tws point to last matching tree_write_stack entry */
ret = tree_write_stack_finish_subtree(tws);
if (ret)
return ret;
/* Start subtrees needed to satisfy path */
while (3 * n + 2 < path_len && path[3 * n + 2] == '/') {
tree_write_stack_init_subtree(tws, path + 3 * n);
n++;
tws = tws->next;
}
/* There should be no more directory components in the given path */
assert(memchr(path + 3 * n, '/', path_len - (3 * n)) == NULL);
/* Finally add given entry to the current tree object */
write_tree_entry(&tws->buf, mode, path + 3 * n, path_len - (3 * n),
oid->hash);
return 0;
}
struct write_each_note_data {
struct tree_write_stack *root;
struct non_note **nn_list;
struct non_note *nn_prev;
};
static int write_each_non_note_until(const char *note_path,
struct write_each_note_data *d)
{
struct non_note *p = d->nn_prev;
struct non_note *n = p ? p->next : *d->nn_list;
int cmp = 0, ret;
while (n && (!note_path || (cmp = strcmp(n->path, note_path)) <= 0)) {
if (note_path && cmp == 0)
; /* do nothing, prefer note to non-note */
else {
ret = write_each_note_helper(d->root, n->path, n->mode,
&n->oid);
if (ret)
return ret;
}
p = n;
n = n->next;
}
d->nn_prev = p;
return 0;
}
static int write_each_note(const struct object_id *object_oid,
const struct object_id *note_oid, char *note_path,
void *cb_data)
{
struct write_each_note_data *d =
(struct write_each_note_data *) cb_data;
size_t note_path_len = strlen(note_path);
unsigned int mode = 0100644;
if (note_path[note_path_len - 1] == '/') {
/* subtree entry */
note_path_len--;
note_path[note_path_len] = '\0';
mode = 040000;
}
assert(note_path_len <= GIT_MAX_HEXSZ + FANOUT_PATH_SEPARATORS);
/* Weave non-note entries into note entries */
return write_each_non_note_until(note_path, d) ||
write_each_note_helper(d->root, note_path, mode, note_oid);
}
struct note_delete_list {
struct note_delete_list *next;
const unsigned char *sha1;
};
static int prune_notes_helper(const struct object_id *object_oid,
const struct object_id *note_oid, char *note_path,
void *cb_data)
{
struct note_delete_list **l = (struct note_delete_list **) cb_data;
struct note_delete_list *n;
if (has_object_file(object_oid))
return 0; /* nothing to do for this note */
/* failed to find object => prune this note */
n = (struct note_delete_list *) xmalloc(sizeof(*n));
n->next = *l;
n->sha1 = object_oid->hash;
*l = n;
return 0;
}
int combine_notes_concatenate(struct object_id *cur_oid,
const struct object_id *new_oid)
{
char *cur_msg = NULL, *new_msg = NULL, *buf;
unsigned long cur_len, new_len, buf_len;
enum object_type cur_type, new_type;
int ret;
/* read in both note blob objects */
if (!is_null_oid(new_oid))
new_msg = read_object_file(new_oid, &new_type, &new_len);
if (!new_msg || !new_len || new_type != OBJ_BLOB) {
free(new_msg);
return 0;
}
if (!is_null_oid(cur_oid))
cur_msg = read_object_file(cur_oid, &cur_type, &cur_len);
if (!cur_msg || !cur_len || cur_type != OBJ_BLOB) {
free(cur_msg);
free(new_msg);
oidcpy(cur_oid, new_oid);
return 0;
}
/* we will separate the notes by two newlines anyway */
if (cur_msg[cur_len - 1] == '\n')
cur_len--;
/* concatenate cur_msg and new_msg into buf */
buf_len = cur_len + 2 + new_len;
buf = (char *) xmalloc(buf_len);
memcpy(buf, cur_msg, cur_len);
buf[cur_len] = '\n';
buf[cur_len + 1] = '\n';
memcpy(buf + cur_len + 2, new_msg, new_len);
free(cur_msg);
free(new_msg);
/* create a new blob object from buf */
ret = write_object_file(buf, buf_len, blob_type, cur_oid);
free(buf);
return ret;
}
int combine_notes_overwrite(struct object_id *cur_oid,
const struct object_id *new_oid)
{
oidcpy(cur_oid, new_oid);
return 0;
}
int combine_notes_ignore(struct object_id *cur_oid,
const struct object_id *new_oid)
{
return 0;
}
/*
* Add the lines from the named object to list, with trailing
* newlines removed.
*/
static int string_list_add_note_lines(struct string_list *list,
const struct object_id *oid)
{
char *data;
unsigned long len;
enum object_type t;
if (is_null_oid(oid))
return 0;
/* read_sha1_file NUL-terminates */
data = read_object_file(oid, &t, &len);
if (t != OBJ_BLOB || !data || !len) {
free(data);
return t != OBJ_BLOB || !data;
}
/*
* If the last line of the file is EOL-terminated, this will
* add an empty string to the list. But it will be removed
* later, along with any empty strings that came from empty
* lines within the file.
*/
string_list_split(list, data, '\n', -1);
free(data);
return 0;
}
static int string_list_join_lines_helper(struct string_list_item *item,
void *cb_data)
{
struct strbuf *buf = cb_data;
strbuf_addstr(buf, item->string);
strbuf_addch(buf, '\n');
return 0;
}
int combine_notes_cat_sort_uniq(struct object_id *cur_oid,
const struct object_id *new_oid)
{
struct string_list sort_uniq_list = STRING_LIST_INIT_DUP;
struct strbuf buf = STRBUF_INIT;
int ret = 1;
/* read both note blob objects into unique_lines */
if (string_list_add_note_lines(&sort_uniq_list, cur_oid))
goto out;
if (string_list_add_note_lines(&sort_uniq_list, new_oid))
goto out;
string_list_remove_empty_items(&sort_uniq_list, 0);
string_list_sort(&sort_uniq_list);
string_list_remove_duplicates(&sort_uniq_list, 0);
/* create a new blob object from sort_uniq_list */
if (for_each_string_list(&sort_uniq_list,
string_list_join_lines_helper, &buf))
goto out;
ret = write_object_file(buf.buf, buf.len, blob_type, cur_oid);
out:
strbuf_release(&buf);
string_list_clear(&sort_uniq_list, 0);
return ret;
}
static int string_list_add_one_ref(const char *refname, const struct object_id *oid,
int flag, void *cb)
{
struct string_list *refs = cb;
if (!unsorted_string_list_has_string(refs, refname))
string_list_append(refs, refname);
return 0;
}
/*
* The list argument must have strdup_strings set on it.
*/
void string_list_add_refs_by_glob(struct string_list *list, const char *glob)
{
assert(list->strdup_strings);
if (has_glob_specials(glob)) {
for_each_glob_ref(string_list_add_one_ref, glob, list);
} else {
struct object_id oid;
if (get_oid(glob, &oid))
warning("notes ref %s is invalid", glob);
if (!unsorted_string_list_has_string(list, glob))
string_list_append(list, glob);
}
}
void string_list_add_refs_from_colon_sep(struct string_list *list,
const char *globs)
{
struct string_list split = STRING_LIST_INIT_NODUP;
char *globs_copy = xstrdup(globs);
int i;
string_list_split_in_place(&split, globs_copy, ':', -1);
string_list_remove_empty_items(&split, 0);
for (i = 0; i < split.nr; i++)
string_list_add_refs_by_glob(list, split.items[i].string);
string_list_clear(&split, 0);
free(globs_copy);
}
static int notes_display_config(const char *k, const char *v, void *cb)
{
int *load_refs = cb;
if (*load_refs && !strcmp(k, "notes.displayref")) {
if (!v)
return config_error_nonbool(k);
string_list_add_refs_by_glob(&display_notes_refs, v);
}
return 0;
}
const char *default_notes_ref(void)
{
const char *notes_ref = NULL;
if (!notes_ref)
notes_ref = getenv(GIT_NOTES_REF_ENVIRONMENT);
if (!notes_ref)
notes_ref = notes_ref_name; /* value of core.notesRef config */
if (!notes_ref)
notes_ref = GIT_NOTES_DEFAULT_REF;
return notes_ref;
}
void init_notes(struct notes_tree *t, const char *notes_ref,
combine_notes_fn combine_notes, int flags)
{
struct object_id oid, object_oid;
unsigned short mode;
struct leaf_node root_tree;
if (!t)
t = &default_notes_tree;
assert(!t->initialized);
if (!notes_ref)
notes_ref = default_notes_ref();
if (!combine_notes)
combine_notes = combine_notes_concatenate;
t->root = (struct int_node *) xcalloc(1, sizeof(struct int_node));
t->first_non_note = NULL;
t->prev_non_note = NULL;
t->ref = xstrdup_or_null(notes_ref);
t->update_ref = (flags & NOTES_INIT_WRITABLE) ? t->ref : NULL;
t->combine_notes = combine_notes;
t->initialized = 1;
t->dirty = 0;
if (flags & NOTES_INIT_EMPTY || !notes_ref ||
get_oid_treeish(notes_ref, &object_oid))
return;
if (flags & NOTES_INIT_WRITABLE && read_ref(notes_ref, &object_oid))
die("Cannot use notes ref %s", notes_ref);
if (get_tree_entry(the_repository, &object_oid, "", &oid, &mode))
die("Failed to read notes tree referenced by %s (%s)",
notes_ref, oid_to_hex(&object_oid));
oidclr(&root_tree.key_oid);
oidcpy(&root_tree.val_oid, &oid);
load_subtree(t, &root_tree, t->root, 0);
}
struct notes_tree **load_notes_trees(struct string_list *refs, int flags)
{
struct string_list_item *item;
int counter = 0;
struct notes_tree **trees;
ALLOC_ARRAY(trees, refs->nr + 1);
for_each_string_list_item(item, refs) {
struct notes_tree *t = xcalloc(1, sizeof(struct notes_tree));
init_notes(t, item->string, combine_notes_ignore, flags);
trees[counter++] = t;
}
trees[counter] = NULL;
return trees;
}
void init_display_notes(struct display_notes_opt *opt)
{
memset(opt, 0, sizeof(*opt));
opt->use_default_notes = -1;
}
void enable_default_display_notes(struct display_notes_opt *opt, int *show_notes)
{
opt->use_default_notes = 1;
*show_notes = 1;
}
void enable_ref_display_notes(struct display_notes_opt *opt, int *show_notes,
const char *ref) {
struct strbuf buf = STRBUF_INIT;
strbuf_addstr(&buf, ref);
expand_notes_ref(&buf);
string_list_append(&opt->extra_notes_refs,
strbuf_detach(&buf, NULL));
*show_notes = 1;
}
void disable_display_notes(struct display_notes_opt *opt, int *show_notes)
{
opt->use_default_notes = -1;
/* we have been strdup'ing ourselves, so trick
* string_list into free()ing strings */
opt->extra_notes_refs.strdup_strings = 1;
string_list_clear(&opt->extra_notes_refs, 0);
opt->extra_notes_refs.strdup_strings = 0;
*show_notes = 0;
}
void load_display_notes(struct display_notes_opt *opt)
{
char *display_ref_env;
int load_config_refs = 0;
display_notes_refs.strdup_strings = 1;
assert(!display_notes_trees);
if (!opt || opt->use_default_notes > 0 ||
(opt->use_default_notes == -1 && !opt->extra_notes_refs.nr)) {
string_list_append(&display_notes_refs, default_notes_ref());
display_ref_env = getenv(GIT_NOTES_DISPLAY_REF_ENVIRONMENT);
if (display_ref_env) {
string_list_add_refs_from_colon_sep(&display_notes_refs,
display_ref_env);
load_config_refs = 0;
} else
load_config_refs = 1;
}
git_config(notes_display_config, &load_config_refs);
if (opt) {
struct string_list_item *item;
for_each_string_list_item(item, &opt->extra_notes_refs)
string_list_add_refs_by_glob(&display_notes_refs,
item->string);
}
display_notes_trees = load_notes_trees(&display_notes_refs, 0);
string_list_clear(&display_notes_refs, 0);
}
int add_note(struct notes_tree *t, const struct object_id *object_oid,
const struct object_id *note_oid, combine_notes_fn combine_notes)
{
struct leaf_node *l;
if (!t)
t = &default_notes_tree;
assert(t->initialized);
t->dirty = 1;
if (!combine_notes)
combine_notes = t->combine_notes;
l = (struct leaf_node *) xmalloc(sizeof(struct leaf_node));
oidcpy(&l->key_oid, object_oid);
oidcpy(&l->val_oid, note_oid);
return note_tree_insert(t, t->root, 0, l, PTR_TYPE_NOTE, combine_notes);
}
int remove_note(struct notes_tree *t, const unsigned char *object_sha1)
{
struct leaf_node l;
if (!t)
t = &default_notes_tree;
assert(t->initialized);
oidread(&l.key_oid, object_sha1);
oidclr(&l.val_oid);
note_tree_remove(t, t->root, 0, &l);
if (is_null_oid(&l.val_oid)) /* no note was removed */
return 1;
t->dirty = 1;
return 0;
}
const struct object_id *get_note(struct notes_tree *t,
const struct object_id *oid)
{
struct leaf_node *found;
if (!t)
t = &default_notes_tree;
assert(t->initialized);
found = note_tree_find(t, t->root, 0, oid->hash);
return found ? &found->val_oid : NULL;
}
int for_each_note(struct notes_tree *t, int flags, each_note_fn fn,
void *cb_data)
{
if (!t)
t = &default_notes_tree;
assert(t->initialized);
return for_each_note_helper(t, t->root, 0, 0, flags, fn, cb_data);
}
int write_notes_tree(struct notes_tree *t, struct object_id *result)
{
struct tree_write_stack root;
struct write_each_note_data cb_data;
int ret;
int flags;
if (!t)
t = &default_notes_tree;
assert(t->initialized);
/* Prepare for traversal of current notes tree */
root.next = NULL; /* last forward entry in list is grounded */
strbuf_init(&root.buf, 256 * (32 + the_hash_algo->hexsz)); /* assume 256 entries */
root.path[0] = root.path[1] = '\0';
cb_data.root = &root;
cb_data.nn_list = &(t->first_non_note);
cb_data.nn_prev = NULL;
/* Write tree objects representing current notes tree */
flags = FOR_EACH_NOTE_DONT_UNPACK_SUBTREES |
FOR_EACH_NOTE_YIELD_SUBTREES;
ret = for_each_note(t, flags, write_each_note, &cb_data) ||
write_each_non_note_until(NULL, &cb_data) ||
tree_write_stack_finish_subtree(&root) ||
write_object_file(root.buf.buf, root.buf.len, tree_type, result);
strbuf_release(&root.buf);
return ret;
}
void prune_notes(struct notes_tree *t, int flags)
{
struct note_delete_list *l = NULL;
if (!t)
t = &default_notes_tree;
assert(t->initialized);
for_each_note(t, 0, prune_notes_helper, &l);
while (l) {
if (flags & NOTES_PRUNE_VERBOSE)
printf("%s\n", hash_to_hex(l->sha1));
if (!(flags & NOTES_PRUNE_DRYRUN))
remove_note(t, l->sha1);
l = l->next;
}
}
void free_notes(struct notes_tree *t)
{
if (!t)
t = &default_notes_tree;
if (t->root)
note_tree_free(t->root);
free(t->root);
while (t->first_non_note) {
t->prev_non_note = t->first_non_note->next;
free(t->first_non_note->path);
free(t->first_non_note);
t->first_non_note = t->prev_non_note;
}
free(t->ref);
memset(t, 0, sizeof(struct notes_tree));
}
/*
* 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.
*
* (raw != 0) gives the %N userformat; otherwise, the note message is given
* for human consumption.
*/
static void format_note(struct notes_tree *t, const struct object_id *object_oid,
struct strbuf *sb, const char *output_encoding, int raw)
{
static const char utf8[] = "utf-8";
const struct object_id *oid;
char *msg, *msg_p;
unsigned long linelen, msglen;
enum object_type type;
if (!t)
t = &default_notes_tree;
if (!t->initialized)
init_notes(t, NULL, NULL, 0);
oid = get_note(t, object_oid);
if (!oid)
return;
if (!(msg = read_object_file(oid, &type, &msglen)) || type != OBJ_BLOB) {
free(msg);
return;
}
if (output_encoding && *output_encoding &&
!is_encoding_utf8(output_encoding)) {
char *reencoded = reencode_string(msg, output_encoding, utf8);
if (reencoded) {
free(msg);
msg = reencoded;
msglen = strlen(msg);
}
}
/* we will end the annotation by a newline anyway */
if (msglen && msg[msglen - 1] == '\n')
msglen--;
if (!raw) {
const char *ref = t->ref;
if (!ref || !strcmp(ref, GIT_NOTES_DEFAULT_REF)) {
strbuf_addstr(sb, "\nNotes:\n");
} else {
skip_prefix(ref, "refs/", &ref);
skip_prefix(ref, "notes/", &ref);
strbuf_addf(sb, "\nNotes (%s):\n", ref);
}
}
for (msg_p = msg; msg_p < msg + msglen; msg_p += linelen + 1) {
linelen = strchrnul(msg_p, '\n') - msg_p;
if (!raw)
strbuf_addstr(sb, " ");
strbuf_add(sb, msg_p, linelen);
strbuf_addch(sb, '\n');
}
free(msg);
}
void format_display_notes(const struct object_id *object_oid,
struct strbuf *sb, const char *output_encoding, int raw)
{
int i;
assert(display_notes_trees);
for (i = 0; display_notes_trees[i]; i++)
format_note(display_notes_trees[i], object_oid, sb,
output_encoding, raw);
}
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)
{
const struct object_id *note = get_note(t, from_obj);
const struct object_id *existing_note = get_note(t, to_obj);
if (!force && existing_note)
return 1;
if (note)
return add_note(t, to_obj, note, combine_notes);
else if (existing_note)
return add_note(t, to_obj, null_oid(), combine_notes);
return 0;
}
void expand_notes_ref(struct strbuf *sb)
{
if (starts_with(sb->buf, "refs/notes/"))
return; /* we're happy */
else if (starts_with(sb->buf, "notes/"))
strbuf_insertstr(sb, 0, "refs/");
else
strbuf_insertstr(sb, 0, "refs/notes/");
}
void expand_loose_notes_ref(struct strbuf *sb)
{
struct object_id object;
if (get_oid(sb->buf, &object)) {
/* fallback to expand_notes_ref */
expand_notes_ref(sb);
}
}