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#include "cache.h"
#include "attr.h"
#include "object.h"
#include "blob.h"
#include "commit.h"
#include "tag.h"
#include "tree.h"
#include "delta.h"
#include "pack.h"
#include "tree-walk.h"
#include "diff.h"
#include "revision.h"
#include "list-objects.h"
#include "progress.h"
#include "refs.h"
#include "khash.h"
#include "pack-bitmap.h"
#include "pack-objects.h"
#include "delta-islands.h"
#include "oid-array.h"
#include "config.h"
KHASH_INIT(str, const char *, void *, 1, kh_str_hash_func, kh_str_hash_equal)
static kh_oid_map_t *island_marks;
static unsigned island_counter;
static unsigned island_counter_core;
static kh_str_t *remote_islands;
struct remote_island {
uint64_t hash;
struct oid_array oids;
};
struct island_bitmap {
uint32_t refcount;
uint32_t bits[FLEX_ARRAY];
};
static uint32_t island_bitmap_size;
/*
* Allocate a new bitmap; if "old" is not NULL, the new bitmap will be a copy
* of "old". Otherwise, the new bitmap is empty.
*/
static struct island_bitmap *island_bitmap_new(const struct island_bitmap *old)
{
size_t size = sizeof(struct island_bitmap) + (island_bitmap_size * 4);
struct island_bitmap *b = xcalloc(1, size);
if (old)
memcpy(b, old, size);
b->refcount = 1;
return b;
}
static void island_bitmap_or(struct island_bitmap *a, const struct island_bitmap *b)
{
uint32_t i;
for (i = 0; i < island_bitmap_size; ++i)
a->bits[i] |= b->bits[i];
}
static int island_bitmap_is_subset(struct island_bitmap *self,
struct island_bitmap *super)
{
uint32_t i;
if (self == super)
return 1;
for (i = 0; i < island_bitmap_size; ++i) {
if ((self->bits[i] & super->bits[i]) != self->bits[i])
return 0;
}
return 1;
}
#define ISLAND_BITMAP_BLOCK(x) (x / 32)
#define ISLAND_BITMAP_MASK(x) (1 << (x % 32))
static void island_bitmap_set(struct island_bitmap *self, uint32_t i)
{
self->bits[ISLAND_BITMAP_BLOCK(i)] |= ISLAND_BITMAP_MASK(i);
}
static int island_bitmap_get(struct island_bitmap *self, uint32_t i)
{
return (self->bits[ISLAND_BITMAP_BLOCK(i)] & ISLAND_BITMAP_MASK(i)) != 0;
}
int in_same_island(const struct object_id *trg_oid, const struct object_id *src_oid)
{
khiter_t trg_pos, src_pos;
/* If we aren't using islands, assume everything goes together. */
if (!island_marks)
return 1;
/*
* If we don't have a bitmap for the target, we can delta it
* against anything -- it's not an important object
*/
trg_pos = kh_get_oid_map(island_marks, *trg_oid);
if (trg_pos >= kh_end(island_marks))
return 1;
/*
* if the source (our delta base) doesn't have a bitmap,
* we don't want to base any deltas on it!
*/
src_pos = kh_get_oid_map(island_marks, *src_oid);
if (src_pos >= kh_end(island_marks))
return 0;
return island_bitmap_is_subset(kh_value(island_marks, trg_pos),
kh_value(island_marks, src_pos));
}
int island_delta_cmp(const struct object_id *a, const struct object_id *b)
{
khiter_t a_pos, b_pos;
struct island_bitmap *a_bitmap = NULL, *b_bitmap = NULL;
if (!island_marks)
return 0;
a_pos = kh_get_oid_map(island_marks, *a);
if (a_pos < kh_end(island_marks))
a_bitmap = kh_value(island_marks, a_pos);
b_pos = kh_get_oid_map(island_marks, *b);
if (b_pos < kh_end(island_marks))
b_bitmap = kh_value(island_marks, b_pos);
if (a_bitmap) {
if (!b_bitmap || !island_bitmap_is_subset(a_bitmap, b_bitmap))
return -1;
}
if (b_bitmap) {
if (!a_bitmap || !island_bitmap_is_subset(b_bitmap, a_bitmap))
return 1;
}
return 0;
}
static struct island_bitmap *create_or_get_island_marks(struct object *obj)
{
khiter_t pos;
int hash_ret;
pos = kh_put_oid_map(island_marks, obj->oid, &hash_ret);
if (hash_ret)
kh_value(island_marks, pos) = island_bitmap_new(NULL);
return kh_value(island_marks, pos);
}
static void set_island_marks(struct object *obj, struct island_bitmap *marks)
{
struct island_bitmap *b;
khiter_t pos;
int hash_ret;
pos = kh_put_oid_map(island_marks, obj->oid, &hash_ret);
if (hash_ret) {
/*
* We don't have one yet; make a copy-on-write of the
* parent.
*/
marks->refcount++;
kh_value(island_marks, pos) = marks;
return;
}
/*
* We do have it. Make sure we split any copy-on-write before
* updating.
*/
b = kh_value(island_marks, pos);
if (b->refcount > 1) {
b->refcount--;
b = kh_value(island_marks, pos) = island_bitmap_new(b);
}
island_bitmap_or(b, marks);
}
static void mark_remote_island_1(struct repository *r,
struct remote_island *rl,
int is_core_island)
{
uint32_t i;
for (i = 0; i < rl->oids.nr; ++i) {
struct island_bitmap *marks;
struct object *obj = parse_object(r, &rl->oids.oid[i]);
if (!obj)
continue;
marks = create_or_get_island_marks(obj);
island_bitmap_set(marks, island_counter);
if (is_core_island && obj->type == OBJ_COMMIT)
obj->flags |= NEEDS_BITMAP;
/* If it was a tag, also make sure we hit the underlying object. */
while (obj && obj->type == OBJ_TAG) {
obj = ((struct tag *)obj)->tagged;
if (obj) {
parse_object(r, &obj->oid);
marks = create_or_get_island_marks(obj);
island_bitmap_set(marks, island_counter);
}
}
}
if (is_core_island)
island_counter_core = island_counter;
island_counter++;
}
struct tree_islands_todo {
struct object_entry *entry;
unsigned int depth;
};
static int tree_depth_compare(const void *a, const void *b)
{
const struct tree_islands_todo *todo_a = a;
const struct tree_islands_todo *todo_b = b;
return todo_a->depth - todo_b->depth;
}
void resolve_tree_islands(struct repository *r,
int progress,
struct packing_data *to_pack)
{
struct progress *progress_state = NULL;
struct tree_islands_todo *todo;
int nr = 0;
int i;
if (!island_marks)
return;
/*
* We process only trees, as commits and tags have already been handled
* (and passed their marks on to root trees, as well. We must make sure
* to process them in descending tree-depth order so that marks
* propagate down the tree properly, even if a sub-tree is found in
* multiple parent trees.
*/
ALLOC_ARRAY(todo, to_pack->nr_objects);
for (i = 0; i < to_pack->nr_objects; i++) {
if (oe_type(&to_pack->objects[i]) == OBJ_TREE) {
todo[nr].entry = &to_pack->objects[i];
todo[nr].depth = oe_tree_depth(to_pack, &to_pack->objects[i]);
nr++;
}
}
QSORT(todo, nr, tree_depth_compare);
if (progress)
progress_state = start_progress(_("Propagating island marks"), nr);
for (i = 0; i < nr; i++) {
struct object_entry *ent = todo[i].entry;
struct island_bitmap *root_marks;
struct tree *tree;
struct tree_desc desc;
struct name_entry entry;
khiter_t pos;
pos = kh_get_oid_map(island_marks, ent->idx.oid);
if (pos >= kh_end(island_marks))
continue;
root_marks = kh_value(island_marks, pos);
tree = lookup_tree(r, &ent->idx.oid);
if (!tree || parse_tree(tree) < 0)
die(_("bad tree object %s"), oid_to_hex(&ent->idx.oid));
init_tree_desc(&desc, tree->buffer, tree->size);
while (tree_entry(&desc, &entry)) {
struct object *obj;
if (S_ISGITLINK(entry.mode))
continue;
obj = lookup_object(r, &entry.oid);
if (!obj)
continue;
set_island_marks(obj, root_marks);
}
free_tree_buffer(tree);
display_progress(progress_state, i+1);
}
stop_progress(&progress_state);
free(todo);
}
static regex_t *island_regexes;
static unsigned int island_regexes_alloc, island_regexes_nr;
static const char *core_island_name;
static int island_config_callback(const char *k, const char *v, void *cb)
{
if (!strcmp(k, "pack.island")) {
struct strbuf re = STRBUF_INIT;
if (!v)
return config_error_nonbool(k);
ALLOC_GROW(island_regexes, island_regexes_nr + 1, island_regexes_alloc);
if (*v != '^')
strbuf_addch(&re, '^');
strbuf_addstr(&re, v);
if (regcomp(&island_regexes[island_regexes_nr], re.buf, REG_EXTENDED))
die(_("failed to load island regex for '%s': %s"), k, re.buf);
strbuf_release(&re);
island_regexes_nr++;
return 0;
}
if (!strcmp(k, "pack.islandcore"))
return git_config_string(&core_island_name, k, v);
return 0;
}
static void add_ref_to_island(const char *island_name, const struct object_id *oid)
{
uint64_t sha_core;
struct remote_island *rl = NULL;
int hash_ret;
khiter_t pos = kh_put_str(remote_islands, island_name, &hash_ret);
if (hash_ret) {
kh_key(remote_islands, pos) = xstrdup(island_name);
kh_value(remote_islands, pos) = xcalloc(1, sizeof(struct remote_island));
}
rl = kh_value(remote_islands, pos);
oid_array_append(&rl->oids, oid);
memcpy(&sha_core, oid->hash, sizeof(uint64_t));
rl->hash += sha_core;
}
static int find_island_for_ref(const char *refname, const struct object_id *oid,
int flags, void *data)
{
/*
* We should advertise 'ARRAY_SIZE(matches) - 2' as the max,
* so we can diagnose below a config with more capture groups
* than we support.
*/
regmatch_t matches[16];
int i, m;
struct strbuf island_name = STRBUF_INIT;
/* walk backwards to get last-one-wins ordering */
for (i = island_regexes_nr - 1; i >= 0; i--) {
if (!regexec(&island_regexes[i], refname,
ARRAY_SIZE(matches), matches, 0))
break;
}
if (i < 0)
return 0;
if (matches[ARRAY_SIZE(matches) - 1].rm_so != -1)
warning(_("island regex from config has "
"too many capture groups (max=%d)"),
(int)ARRAY_SIZE(matches) - 2);
for (m = 1; m < ARRAY_SIZE(matches); m++) {
regmatch_t *match = &matches[m];
if (match->rm_so == -1)
continue;
if (island_name.len)
strbuf_addch(&island_name, '-');
strbuf_add(&island_name, refname + match->rm_so, match->rm_eo - match->rm_so);
}
add_ref_to_island(island_name.buf, oid);
strbuf_release(&island_name);
return 0;
}
static struct remote_island *get_core_island(void)
{
if (core_island_name) {
khiter_t pos = kh_get_str(remote_islands, core_island_name);
if (pos < kh_end(remote_islands))
return kh_value(remote_islands, pos);
}
return NULL;
}
static void deduplicate_islands(struct repository *r)
{
struct remote_island *island, *core = NULL, **list;
unsigned int island_count, dst, src, ref, i = 0;
island_count = kh_size(remote_islands);
ALLOC_ARRAY(list, island_count);
kh_foreach_value(remote_islands, island, {
list[i++] = island;
});
for (ref = 0; ref + 1 < island_count; ref++) {
for (src = ref + 1, dst = src; src < island_count; src++) {
if (list[ref]->hash == list[src]->hash)
continue;
if (src != dst)
list[dst] = list[src];
dst++;
}
island_count = dst;
}
island_bitmap_size = (island_count / 32) + 1;
core = get_core_island();
for (i = 0; i < island_count; ++i) {
mark_remote_island_1(r, list[i], core && list[i]->hash == core->hash);
}
free(list);
}
void load_delta_islands(struct repository *r, int progress)
{
island_marks = kh_init_oid_map();
remote_islands = kh_init_str();
git_config(island_config_callback, NULL);
for_each_ref(find_island_for_ref, NULL);
deduplicate_islands(r);
if (progress)
fprintf(stderr, _("Marked %d islands, done.\n"), island_counter);
}
void propagate_island_marks(struct commit *commit)
{
khiter_t pos = kh_get_oid_map(island_marks, commit->object.oid);
if (pos < kh_end(island_marks)) {
struct commit_list *p;
struct island_bitmap *root_marks = kh_value(island_marks, pos);
parse_commit(commit);
set_island_marks(&get_commit_tree(commit)->object, root_marks);
for (p = commit->parents; p; p = p->next)
set_island_marks(&p->item->object, root_marks);
}
}
int compute_pack_layers(struct packing_data *to_pack)
{
uint32_t i;
if (!core_island_name || !island_marks)
return 1;
for (i = 0; i < to_pack->nr_objects; ++i) {
struct object_entry *entry = &to_pack->objects[i];
khiter_t pos = kh_get_oid_map(island_marks, entry->idx.oid);
oe_set_layer(to_pack, entry, 1);
if (pos < kh_end(island_marks)) {
struct island_bitmap *bitmap = kh_value(island_marks, pos);
if (island_bitmap_get(bitmap, island_counter_core))
oe_set_layer(to_pack, entry, 0);
}
}
return 2;
}