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-rw-r--r--cache-tree.c975
1 files changed, 975 insertions, 0 deletions
diff --git a/cache-tree.c b/cache-tree.c
new file mode 100644
index 0000000..c97111c
--- /dev/null
+++ b/cache-tree.c
@@ -0,0 +1,975 @@
+#include "cache.h"
+#include "lockfile.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "cache-tree.h"
+#include "bulk-checkin.h"
+#include "object-store.h"
+#include "replace-object.h"
+#include "promisor-remote.h"
+#include "sparse-index.h"
+
+#ifndef DEBUG_CACHE_TREE
+#define DEBUG_CACHE_TREE 0
+#endif
+
+struct cache_tree *cache_tree(void)
+{
+ struct cache_tree *it = xcalloc(1, sizeof(struct cache_tree));
+ it->entry_count = -1;
+ return it;
+}
+
+void cache_tree_free(struct cache_tree **it_p)
+{
+ int i;
+ struct cache_tree *it = *it_p;
+
+ if (!it)
+ return;
+ for (i = 0; i < it->subtree_nr; i++)
+ if (it->down[i]) {
+ cache_tree_free(&it->down[i]->cache_tree);
+ free(it->down[i]);
+ }
+ free(it->down);
+ free(it);
+ *it_p = NULL;
+}
+
+static int subtree_name_cmp(const char *one, int onelen,
+ const char *two, int twolen)
+{
+ if (onelen < twolen)
+ return -1;
+ if (twolen < onelen)
+ return 1;
+ return memcmp(one, two, onelen);
+}
+
+int cache_tree_subtree_pos(struct cache_tree *it, const char *path, int pathlen)
+{
+ struct cache_tree_sub **down = it->down;
+ int lo, hi;
+ lo = 0;
+ hi = it->subtree_nr;
+ while (lo < hi) {
+ int mi = lo + (hi - lo) / 2;
+ struct cache_tree_sub *mdl = down[mi];
+ int cmp = subtree_name_cmp(path, pathlen,
+ mdl->name, mdl->namelen);
+ if (!cmp)
+ return mi;
+ if (cmp < 0)
+ hi = mi;
+ else
+ lo = mi + 1;
+ }
+ return -lo-1;
+}
+
+static struct cache_tree_sub *find_subtree(struct cache_tree *it,
+ const char *path,
+ int pathlen,
+ int create)
+{
+ struct cache_tree_sub *down;
+ int pos = cache_tree_subtree_pos(it, path, pathlen);
+ if (0 <= pos)
+ return it->down[pos];
+ if (!create)
+ return NULL;
+
+ pos = -pos-1;
+ ALLOC_GROW(it->down, it->subtree_nr + 1, it->subtree_alloc);
+ it->subtree_nr++;
+
+ FLEX_ALLOC_MEM(down, name, path, pathlen);
+ down->cache_tree = NULL;
+ down->namelen = pathlen;
+
+ if (pos < it->subtree_nr)
+ MOVE_ARRAY(it->down + pos + 1, it->down + pos,
+ it->subtree_nr - pos - 1);
+ it->down[pos] = down;
+ return down;
+}
+
+struct cache_tree_sub *cache_tree_sub(struct cache_tree *it, const char *path)
+{
+ int pathlen = strlen(path);
+ return find_subtree(it, path, pathlen, 1);
+}
+
+static int do_invalidate_path(struct cache_tree *it, const char *path)
+{
+ /* a/b/c
+ * ==> invalidate self
+ * ==> find "a", have it invalidate "b/c"
+ * a
+ * ==> invalidate self
+ * ==> if "a" exists as a subtree, remove it.
+ */
+ const char *slash;
+ int namelen;
+ struct cache_tree_sub *down;
+
+#if DEBUG_CACHE_TREE
+ fprintf(stderr, "cache-tree invalidate <%s>\n", path);
+#endif
+
+ if (!it)
+ return 0;
+ slash = strchrnul(path, '/');
+ namelen = slash - path;
+ it->entry_count = -1;
+ if (!*slash) {
+ int pos;
+ pos = cache_tree_subtree_pos(it, path, namelen);
+ if (0 <= pos) {
+ cache_tree_free(&it->down[pos]->cache_tree);
+ free(it->down[pos]);
+ /* 0 1 2 3 4 5
+ * ^ ^subtree_nr = 6
+ * pos
+ * move 4 and 5 up one place (2 entries)
+ * 2 = 6 - 3 - 1 = subtree_nr - pos - 1
+ */
+ MOVE_ARRAY(it->down + pos, it->down + pos + 1,
+ it->subtree_nr - pos - 1);
+ it->subtree_nr--;
+ }
+ return 1;
+ }
+ down = find_subtree(it, path, namelen, 0);
+ if (down)
+ do_invalidate_path(down->cache_tree, slash + 1);
+ return 1;
+}
+
+void cache_tree_invalidate_path(struct index_state *istate, const char *path)
+{
+ if (do_invalidate_path(istate->cache_tree, path))
+ istate->cache_changed |= CACHE_TREE_CHANGED;
+}
+
+static int verify_cache(struct index_state *istate, int flags)
+{
+ unsigned i, funny;
+ int silent = flags & WRITE_TREE_SILENT;
+
+ /* Verify that the tree is merged */
+ funny = 0;
+ for (i = 0; i < istate->cache_nr; i++) {
+ const struct cache_entry *ce = istate->cache[i];
+ if (ce_stage(ce)) {
+ if (silent)
+ return -1;
+ if (10 < ++funny) {
+ fprintf(stderr, "...\n");
+ break;
+ }
+ fprintf(stderr, "%s: unmerged (%s)\n",
+ ce->name, oid_to_hex(&ce->oid));
+ }
+ }
+ if (funny)
+ return -1;
+
+ /* Also verify that the cache does not have path and path/file
+ * at the same time. At this point we know the cache has only
+ * stage 0 entries.
+ */
+ funny = 0;
+ for (i = 0; i + 1 < istate->cache_nr; i++) {
+ /* path/file always comes after path because of the way
+ * the cache is sorted. Also path can appear only once,
+ * which means conflicting one would immediately follow.
+ */
+ const struct cache_entry *this_ce = istate->cache[i];
+ const struct cache_entry *next_ce = istate->cache[i + 1];
+ const char *this_name = this_ce->name;
+ const char *next_name = next_ce->name;
+ int this_len = ce_namelen(this_ce);
+ if (this_len < ce_namelen(next_ce) &&
+ next_name[this_len] == '/' &&
+ strncmp(this_name, next_name, this_len) == 0) {
+ if (10 < ++funny) {
+ fprintf(stderr, "...\n");
+ break;
+ }
+ fprintf(stderr, "You have both %s and %s\n",
+ this_name, next_name);
+ }
+ }
+ if (funny)
+ return -1;
+ return 0;
+}
+
+static void discard_unused_subtrees(struct cache_tree *it)
+{
+ struct cache_tree_sub **down = it->down;
+ int nr = it->subtree_nr;
+ int dst, src;
+ for (dst = src = 0; src < nr; src++) {
+ struct cache_tree_sub *s = down[src];
+ if (s->used)
+ down[dst++] = s;
+ else {
+ cache_tree_free(&s->cache_tree);
+ free(s);
+ it->subtree_nr--;
+ }
+ }
+}
+
+int cache_tree_fully_valid(struct cache_tree *it)
+{
+ int i;
+ if (!it)
+ return 0;
+ if (it->entry_count < 0 || !has_object_file(&it->oid))
+ return 0;
+ for (i = 0; i < it->subtree_nr; i++) {
+ if (!cache_tree_fully_valid(it->down[i]->cache_tree))
+ return 0;
+ }
+ return 1;
+}
+
+static int must_check_existence(const struct cache_entry *ce)
+{
+ return !(has_promisor_remote() && ce_skip_worktree(ce));
+}
+
+static int update_one(struct cache_tree *it,
+ struct cache_entry **cache,
+ int entries,
+ const char *base,
+ int baselen,
+ int *skip_count,
+ int flags)
+{
+ struct strbuf buffer;
+ int missing_ok = flags & WRITE_TREE_MISSING_OK;
+ int dryrun = flags & WRITE_TREE_DRY_RUN;
+ int repair = flags & WRITE_TREE_REPAIR;
+ int to_invalidate = 0;
+ int i;
+
+ assert(!(dryrun && repair));
+
+ *skip_count = 0;
+
+ /*
+ * If the first entry of this region is a sparse directory
+ * entry corresponding exactly to 'base', then this cache_tree
+ * struct is a "leaf" in the data structure, pointing to the
+ * tree OID specified in the entry.
+ */
+ if (entries > 0) {
+ const struct cache_entry *ce = cache[0];
+
+ if (S_ISSPARSEDIR(ce->ce_mode) &&
+ ce->ce_namelen == baselen &&
+ !strncmp(ce->name, base, baselen)) {
+ it->entry_count = 1;
+ oidcpy(&it->oid, &ce->oid);
+ return 1;
+ }
+ }
+
+ if (0 <= it->entry_count && has_object_file(&it->oid))
+ return it->entry_count;
+
+ /*
+ * We first scan for subtrees and update them; we start by
+ * marking existing subtrees -- the ones that are unmarked
+ * should not be in the result.
+ */
+ for (i = 0; i < it->subtree_nr; i++)
+ it->down[i]->used = 0;
+
+ /*
+ * Find the subtrees and update them.
+ */
+ i = 0;
+ while (i < entries) {
+ const struct cache_entry *ce = cache[i];
+ struct cache_tree_sub *sub;
+ const char *path, *slash;
+ int pathlen, sublen, subcnt, subskip;
+
+ path = ce->name;
+ pathlen = ce_namelen(ce);
+ if (pathlen <= baselen || memcmp(base, path, baselen))
+ break; /* at the end of this level */
+
+ slash = strchr(path + baselen, '/');
+ if (!slash) {
+ i++;
+ continue;
+ }
+ /*
+ * a/bbb/c (base = a/, slash = /c)
+ * ==>
+ * path+baselen = bbb/c, sublen = 3
+ */
+ sublen = slash - (path + baselen);
+ sub = find_subtree(it, path + baselen, sublen, 1);
+ if (!sub->cache_tree)
+ sub->cache_tree = cache_tree();
+ subcnt = update_one(sub->cache_tree,
+ cache + i, entries - i,
+ path,
+ baselen + sublen + 1,
+ &subskip,
+ flags);
+ if (subcnt < 0)
+ return subcnt;
+ if (!subcnt)
+ die("index cache-tree records empty sub-tree");
+ i += subcnt;
+ sub->count = subcnt; /* to be used in the next loop */
+ *skip_count += subskip;
+ sub->used = 1;
+ }
+
+ discard_unused_subtrees(it);
+
+ /*
+ * Then write out the tree object for this level.
+ */
+ strbuf_init(&buffer, 8192);
+
+ i = 0;
+ while (i < entries) {
+ const struct cache_entry *ce = cache[i];
+ struct cache_tree_sub *sub = NULL;
+ const char *path, *slash;
+ int pathlen, entlen;
+ const struct object_id *oid;
+ unsigned mode;
+ int expected_missing = 0;
+ int contains_ita = 0;
+ int ce_missing_ok;
+
+ path = ce->name;
+ pathlen = ce_namelen(ce);
+ if (pathlen <= baselen || memcmp(base, path, baselen))
+ break; /* at the end of this level */
+
+ slash = strchr(path + baselen, '/');
+ if (slash) {
+ entlen = slash - (path + baselen);
+ sub = find_subtree(it, path + baselen, entlen, 0);
+ if (!sub)
+ die("cache-tree.c: '%.*s' in '%s' not found",
+ entlen, path + baselen, path);
+ i += sub->count;
+ oid = &sub->cache_tree->oid;
+ mode = S_IFDIR;
+ contains_ita = sub->cache_tree->entry_count < 0;
+ if (contains_ita) {
+ to_invalidate = 1;
+ expected_missing = 1;
+ }
+ }
+ else {
+ oid = &ce->oid;
+ mode = ce->ce_mode;
+ entlen = pathlen - baselen;
+ i++;
+ }
+
+ ce_missing_ok = mode == S_IFGITLINK || missing_ok ||
+ !must_check_existence(ce);
+ if (is_null_oid(oid) ||
+ (!ce_missing_ok && !has_object_file(oid))) {
+ strbuf_release(&buffer);
+ if (expected_missing)
+ return -1;
+ return error("invalid object %06o %s for '%.*s'",
+ mode, oid_to_hex(oid), entlen+baselen, path);
+ }
+
+ /*
+ * CE_REMOVE entries are removed before the index is
+ * written to disk. Skip them to remain consistent
+ * with the future on-disk index.
+ */
+ if (ce->ce_flags & CE_REMOVE) {
+ *skip_count = *skip_count + 1;
+ continue;
+ }
+
+ /*
+ * CE_INTENT_TO_ADD entries exist on on-disk index but
+ * they are not part of generated trees. Invalidate up
+ * to root to force cache-tree users to read elsewhere.
+ */
+ if (!sub && ce_intent_to_add(ce)) {
+ to_invalidate = 1;
+ continue;
+ }
+
+ /*
+ * "sub" can be an empty tree if all subentries are i-t-a.
+ */
+ if (contains_ita && is_empty_tree_oid(oid))
+ continue;
+
+ strbuf_grow(&buffer, entlen + 100);
+ strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
+ strbuf_add(&buffer, oid->hash, the_hash_algo->rawsz);
+
+#if DEBUG_CACHE_TREE
+ fprintf(stderr, "cache-tree update-one %o %.*s\n",
+ mode, entlen, path + baselen);
+#endif
+ }
+
+ if (repair) {
+ struct object_id oid;
+ hash_object_file(the_hash_algo, buffer.buf, buffer.len,
+ OBJ_TREE, &oid);
+ if (has_object_file_with_flags(&oid, OBJECT_INFO_SKIP_FETCH_OBJECT))
+ oidcpy(&it->oid, &oid);
+ else
+ to_invalidate = 1;
+ } else if (dryrun) {
+ hash_object_file(the_hash_algo, buffer.buf, buffer.len,
+ OBJ_TREE, &it->oid);
+ } else if (write_object_file_flags(buffer.buf, buffer.len, OBJ_TREE,
+ &it->oid, flags & WRITE_TREE_SILENT
+ ? HASH_SILENT : 0)) {
+ strbuf_release(&buffer);
+ return -1;
+ }
+
+ strbuf_release(&buffer);
+ it->entry_count = to_invalidate ? -1 : i - *skip_count;
+#if DEBUG_CACHE_TREE
+ fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
+ it->entry_count, it->subtree_nr,
+ oid_to_hex(&it->oid));
+#endif
+ return i;
+}
+
+int cache_tree_update(struct index_state *istate, int flags)
+{
+ int skip, i;
+
+ i = verify_cache(istate, flags);
+
+ if (i)
+ return i;
+
+ if (!istate->cache_tree)
+ istate->cache_tree = cache_tree();
+
+ if (!(flags & WRITE_TREE_MISSING_OK) && has_promisor_remote())
+ prefetch_cache_entries(istate, must_check_existence);
+
+ trace_performance_enter();
+ trace2_region_enter("cache_tree", "update", the_repository);
+ begin_odb_transaction();
+ i = update_one(istate->cache_tree, istate->cache, istate->cache_nr,
+ "", 0, &skip, flags);
+ end_odb_transaction();
+ trace2_region_leave("cache_tree", "update", the_repository);
+ trace_performance_leave("cache_tree_update");
+ if (i < 0)
+ return i;
+ istate->cache_changed |= CACHE_TREE_CHANGED;
+ return 0;
+}
+
+static void write_one(struct strbuf *buffer, struct cache_tree *it,
+ const char *path, int pathlen)
+{
+ int i;
+
+ /* One "cache-tree" entry consists of the following:
+ * path (NUL terminated)
+ * entry_count, subtree_nr ("%d %d\n")
+ * tree-sha1 (missing if invalid)
+ * subtree_nr "cache-tree" entries for subtrees.
+ */
+ strbuf_grow(buffer, pathlen + 100);
+ strbuf_add(buffer, path, pathlen);
+ strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
+
+#if DEBUG_CACHE_TREE
+ if (0 <= it->entry_count)
+ fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
+ pathlen, path, it->entry_count, it->subtree_nr,
+ oid_to_hex(&it->oid));
+ else
+ fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n",
+ pathlen, path, it->subtree_nr);
+#endif
+
+ if (0 <= it->entry_count) {
+ strbuf_add(buffer, it->oid.hash, the_hash_algo->rawsz);
+ }
+ for (i = 0; i < it->subtree_nr; i++) {
+ struct cache_tree_sub *down = it->down[i];
+ if (i) {
+ struct cache_tree_sub *prev = it->down[i-1];
+ if (subtree_name_cmp(down->name, down->namelen,
+ prev->name, prev->namelen) <= 0)
+ die("fatal - unsorted cache subtree");
+ }
+ write_one(buffer, down->cache_tree, down->name, down->namelen);
+ }
+}
+
+void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
+{
+ trace2_region_enter("cache_tree", "write", the_repository);
+ write_one(sb, root, "", 0);
+ trace2_region_leave("cache_tree", "write", the_repository);
+}
+
+static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
+{
+ const char *buf = *buffer;
+ unsigned long size = *size_p;
+ const char *cp;
+ char *ep;
+ struct cache_tree *it;
+ int i, subtree_nr;
+ const unsigned rawsz = the_hash_algo->rawsz;
+
+ it = NULL;
+ /* skip name, but make sure name exists */
+ while (size && *buf) {
+ size--;
+ buf++;
+ }
+ if (!size)
+ goto free_return;
+ buf++; size--;
+ it = cache_tree();
+
+ cp = buf;
+ it->entry_count = strtol(cp, &ep, 10);
+ if (cp == ep)
+ goto free_return;
+ cp = ep;
+ subtree_nr = strtol(cp, &ep, 10);
+ if (cp == ep)
+ goto free_return;
+ while (size && *buf && *buf != '\n') {
+ size--;
+ buf++;
+ }
+ if (!size)
+ goto free_return;
+ buf++; size--;
+ if (0 <= it->entry_count) {
+ if (size < rawsz)
+ goto free_return;
+ oidread(&it->oid, (const unsigned char *)buf);
+ buf += rawsz;
+ size -= rawsz;
+ }
+
+#if DEBUG_CACHE_TREE
+ if (0 <= it->entry_count)
+ fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
+ *buffer, it->entry_count, subtree_nr,
+ oid_to_hex(&it->oid));
+ else
+ fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n",
+ *buffer, subtree_nr);
+#endif
+
+ /*
+ * Just a heuristic -- we do not add directories that often but
+ * we do not want to have to extend it immediately when we do,
+ * hence +2.
+ */
+ it->subtree_alloc = subtree_nr + 2;
+ CALLOC_ARRAY(it->down, it->subtree_alloc);
+ for (i = 0; i < subtree_nr; i++) {
+ /* read each subtree */
+ struct cache_tree *sub;
+ struct cache_tree_sub *subtree;
+ const char *name = buf;
+
+ sub = read_one(&buf, &size);
+ if (!sub)
+ goto free_return;
+ subtree = cache_tree_sub(it, name);
+ subtree->cache_tree = sub;
+ }
+ if (subtree_nr != it->subtree_nr)
+ die("cache-tree: internal error");
+ *buffer = buf;
+ *size_p = size;
+ return it;
+
+ free_return:
+ cache_tree_free(&it);
+ return NULL;
+}
+
+struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
+{
+ struct cache_tree *result;
+
+ if (buffer[0])
+ return NULL; /* not the whole tree */
+
+ trace2_region_enter("cache_tree", "read", the_repository);
+ result = read_one(&buffer, &size);
+ trace2_region_leave("cache_tree", "read", the_repository);
+
+ return result;
+}
+
+static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *path)
+{
+ if (!it)
+ return NULL;
+ while (*path) {
+ const char *slash;
+ struct cache_tree_sub *sub;
+
+ slash = strchrnul(path, '/');
+ /*
+ * Between path and slash is the name of the subtree
+ * to look for.
+ */
+ sub = find_subtree(it, path, slash - path, 0);
+ if (!sub)
+ return NULL;
+ it = sub->cache_tree;
+
+ path = slash;
+ while (*path == '/')
+ path++;
+ }
+ return it;
+}
+
+static int write_index_as_tree_internal(struct object_id *oid,
+ struct index_state *index_state,
+ int cache_tree_valid,
+ int flags,
+ const char *prefix)
+{
+ if (flags & WRITE_TREE_IGNORE_CACHE_TREE) {
+ cache_tree_free(&index_state->cache_tree);
+ cache_tree_valid = 0;
+ }
+
+ if (!cache_tree_valid && cache_tree_update(index_state, flags) < 0)
+ return WRITE_TREE_UNMERGED_INDEX;
+
+ if (prefix) {
+ struct cache_tree *subtree;
+ subtree = cache_tree_find(index_state->cache_tree, prefix);
+ if (!subtree)
+ return WRITE_TREE_PREFIX_ERROR;
+ oidcpy(oid, &subtree->oid);
+ }
+ else
+ oidcpy(oid, &index_state->cache_tree->oid);
+
+ return 0;
+}
+
+struct tree* write_in_core_index_as_tree(struct repository *repo) {
+ struct object_id o;
+ int was_valid, ret;
+
+ struct index_state *index_state = repo->index;
+ was_valid = index_state->cache_tree &&
+ cache_tree_fully_valid(index_state->cache_tree);
+
+ ret = write_index_as_tree_internal(&o, index_state, was_valid, 0, NULL);
+ if (ret == WRITE_TREE_UNMERGED_INDEX) {
+ int i;
+ bug("there are unmerged index entries:");
+ for (i = 0; i < index_state->cache_nr; i++) {
+ const struct cache_entry *ce = index_state->cache[i];
+ if (ce_stage(ce))
+ bug("%d %.*s", ce_stage(ce),
+ (int)ce_namelen(ce), ce->name);
+ }
+ BUG("unmerged index entries when writing in-core index");
+ }
+
+ return lookup_tree(repo, &index_state->cache_tree->oid);
+}
+
+
+int write_index_as_tree(struct object_id *oid, struct index_state *index_state, const char *index_path, int flags, const char *prefix)
+{
+ int entries, was_valid;
+ struct lock_file lock_file = LOCK_INIT;
+ int ret;
+
+ hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
+
+ entries = read_index_from(index_state, index_path, get_git_dir());
+ if (entries < 0) {
+ ret = WRITE_TREE_UNREADABLE_INDEX;
+ goto out;
+ }
+
+ was_valid = !(flags & WRITE_TREE_IGNORE_CACHE_TREE) &&
+ index_state->cache_tree &&
+ cache_tree_fully_valid(index_state->cache_tree);
+
+ ret = write_index_as_tree_internal(oid, index_state, was_valid, flags,
+ prefix);
+ if (!ret && !was_valid) {
+ write_locked_index(index_state, &lock_file, COMMIT_LOCK);
+ /* Not being able to write is fine -- we are only interested
+ * in updating the cache-tree part, and if the next caller
+ * ends up using the old index with unupdated cache-tree part
+ * it misses the work we did here, but that is just a
+ * performance penalty and not a big deal.
+ */
+ }
+
+out:
+ rollback_lock_file(&lock_file);
+ return ret;
+}
+
+static void prime_cache_tree_sparse_dir(struct cache_tree *it,
+ struct tree *tree)
+{
+
+ oidcpy(&it->oid, &tree->object.oid);
+ it->entry_count = 1;
+}
+
+static void prime_cache_tree_rec(struct repository *r,
+ struct cache_tree *it,
+ struct tree *tree,
+ struct strbuf *tree_path)
+{
+ struct tree_desc desc;
+ struct name_entry entry;
+ int cnt;
+ int base_path_len = tree_path->len;
+
+ oidcpy(&it->oid, &tree->object.oid);
+
+ init_tree_desc(&desc, tree->buffer, tree->size);
+ cnt = 0;
+ while (tree_entry(&desc, &entry)) {
+ if (!S_ISDIR(entry.mode))
+ cnt++;
+ else {
+ struct cache_tree_sub *sub;
+ struct tree *subtree = lookup_tree(r, &entry.oid);
+
+ if (!subtree->object.parsed)
+ parse_tree(subtree);
+ sub = cache_tree_sub(it, entry.path);
+ sub->cache_tree = cache_tree();
+
+ /*
+ * Recursively-constructed subtree path is only needed when working
+ * in a sparse index (where it's used to determine whether the
+ * subtree is a sparse directory in the index).
+ */
+ if (r->index->sparse_index) {
+ strbuf_setlen(tree_path, base_path_len);
+ strbuf_grow(tree_path, base_path_len + entry.pathlen + 1);
+ strbuf_add(tree_path, entry.path, entry.pathlen);
+ strbuf_addch(tree_path, '/');
+ }
+
+ /*
+ * If a sparse index is in use, the directory being processed may be
+ * sparse. To confirm that, we can check whether an entry with that
+ * exact name exists in the index. If it does, the created subtree
+ * should be sparse. Otherwise, cache tree expansion should continue
+ * as normal.
+ */
+ if (r->index->sparse_index &&
+ index_entry_exists(r->index, tree_path->buf, tree_path->len))
+ prime_cache_tree_sparse_dir(sub->cache_tree, subtree);
+ else
+ prime_cache_tree_rec(r, sub->cache_tree, subtree, tree_path);
+ cnt += sub->cache_tree->entry_count;
+ }
+ }
+
+ it->entry_count = cnt;
+}
+
+void prime_cache_tree(struct repository *r,
+ struct index_state *istate,
+ struct tree *tree)
+{
+ struct strbuf tree_path = STRBUF_INIT;
+
+ trace2_region_enter("cache-tree", "prime_cache_tree", the_repository);
+ cache_tree_free(&istate->cache_tree);
+ istate->cache_tree = cache_tree();
+
+ prime_cache_tree_rec(r, istate->cache_tree, tree, &tree_path);
+ strbuf_release(&tree_path);
+ istate->cache_changed |= CACHE_TREE_CHANGED;
+ trace2_region_leave("cache-tree", "prime_cache_tree", the_repository);
+}
+
+/*
+ * find the cache_tree that corresponds to the current level without
+ * exploding the full path into textual form. The root of the
+ * cache tree is given as "root", and our current level is "info".
+ * (1) When at root level, info->prev is NULL, so it is "root" itself.
+ * (2) Otherwise, find the cache_tree that corresponds to one level
+ * above us, and find ourselves in there.
+ */
+static struct cache_tree *find_cache_tree_from_traversal(struct cache_tree *root,
+ struct traverse_info *info)
+{
+ struct cache_tree *our_parent;
+
+ if (!info->prev)
+ return root;
+ our_parent = find_cache_tree_from_traversal(root, info->prev);
+ return cache_tree_find(our_parent, info->name);
+}
+
+int cache_tree_matches_traversal(struct cache_tree *root,
+ struct name_entry *ent,
+ struct traverse_info *info)
+{
+ struct cache_tree *it;
+
+ it = find_cache_tree_from_traversal(root, info);
+ it = cache_tree_find(it, ent->path);
+ if (it && it->entry_count > 0 && oideq(&ent->oid, &it->oid))
+ return it->entry_count;
+ return 0;
+}
+
+static void verify_one_sparse(struct index_state *istate,
+ struct strbuf *path,
+ int pos)
+{
+ struct cache_entry *ce = istate->cache[pos];
+
+ if (!S_ISSPARSEDIR(ce->ce_mode))
+ BUG("directory '%s' is present in index, but not sparse",
+ path->buf);
+}
+
+/*
+ * Returns:
+ * 0 - Verification completed.
+ * 1 - Restart verification - a call to ensure_full_index() freed the cache
+ * tree that is being verified and verification needs to be restarted from
+ * the new toplevel cache tree.
+ */
+static int verify_one(struct repository *r,
+ struct index_state *istate,
+ struct cache_tree *it,
+ struct strbuf *path)
+{
+ int i, pos, len = path->len;
+ struct strbuf tree_buf = STRBUF_INIT;
+ struct object_id new_oid;
+
+ for (i = 0; i < it->subtree_nr; i++) {
+ strbuf_addf(path, "%s/", it->down[i]->name);
+ if (verify_one(r, istate, it->down[i]->cache_tree, path))
+ return 1;
+ strbuf_setlen(path, len);
+ }
+
+ if (it->entry_count < 0 ||
+ /* no verification on tests (t7003) that replace trees */
+ lookup_replace_object(r, &it->oid) != &it->oid)
+ return 0;
+
+ if (path->len) {
+ /*
+ * If the index is sparse and the cache tree is not
+ * index_name_pos() may trigger ensure_full_index() which will
+ * free the tree that is being verified.
+ */
+ int is_sparse = istate->sparse_index;
+ pos = index_name_pos(istate, path->buf, path->len);
+ if (is_sparse && !istate->sparse_index)
+ return 1;
+
+ if (pos >= 0) {
+ verify_one_sparse(istate, path, pos);
+ return 0;
+ }
+
+ pos = -pos - 1;
+ } else {
+ pos = 0;
+ }
+
+ i = 0;
+ while (i < it->entry_count) {
+ struct cache_entry *ce = istate->cache[pos + i];
+ const char *slash;
+ struct cache_tree_sub *sub = NULL;
+ const struct object_id *oid;
+ const char *name;
+ unsigned mode;
+ int entlen;
+
+ if (ce->ce_flags & (CE_STAGEMASK | CE_INTENT_TO_ADD | CE_REMOVE))
+ BUG("%s with flags 0x%x should not be in cache-tree",
+ ce->name, ce->ce_flags);
+ name = ce->name + path->len;
+ slash = strchr(name, '/');
+ if (slash) {
+ entlen = slash - name;
+ sub = find_subtree(it, ce->name + path->len, entlen, 0);
+ if (!sub || sub->cache_tree->entry_count < 0)
+ BUG("bad subtree '%.*s'", entlen, name);
+ oid = &sub->cache_tree->oid;
+ mode = S_IFDIR;
+ i += sub->cache_tree->entry_count;
+ } else {
+ oid = &ce->oid;
+ mode = ce->ce_mode;
+ entlen = ce_namelen(ce) - path->len;
+ i++;
+ }
+ strbuf_addf(&tree_buf, "%o %.*s%c", mode, entlen, name, '\0');
+ strbuf_add(&tree_buf, oid->hash, r->hash_algo->rawsz);
+ }
+ hash_object_file(r->hash_algo, tree_buf.buf, tree_buf.len, OBJ_TREE,
+ &new_oid);
+ if (!oideq(&new_oid, &it->oid))
+ BUG("cache-tree for path %.*s does not match. "
+ "Expected %s got %s", len, path->buf,
+ oid_to_hex(&new_oid), oid_to_hex(&it->oid));
+ strbuf_setlen(path, len);
+ strbuf_release(&tree_buf);
+ return 0;
+}
+
+void cache_tree_verify(struct repository *r, struct index_state *istate)
+{
+ struct strbuf path = STRBUF_INIT;
+
+ if (!istate->cache_tree)
+ return;
+ if (verify_one(r, istate, istate->cache_tree, &path)) {
+ strbuf_reset(&path);
+ if (verify_one(r, istate, istate->cache_tree, &path))
+ BUG("ensure_full_index() called twice while verifying cache tree");
+ }
+ strbuf_release(&path);
+}