Imported Upstream version 2.21.0
[platform/upstream/git.git] / unpack-trees.c
index e30e011..3563daa 100644 (file)
@@ -1,5 +1,5 @@
-#define NO_THE_INDEX_COMPATIBILITY_MACROS
 #include "cache.h"
+#include "argv-array.h"
 #include "repository.h"
 #include "config.h"
 #include "dir.h"
@@ -15,6 +15,8 @@
 #include "submodule.h"
 #include "submodule-config.h"
 #include "fsmonitor.h"
+#include "object-store.h"
+#include "fetch-object.h"
 
 /*
  * Error messages expected by scripts out of plumbing commands such as
@@ -102,6 +104,8 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
        const char **msgs = opts->msgs;
        const char *msg;
 
+       argv_array_init(&opts->msgs_to_free);
+
        if (!strcmp(cmd, "checkout"))
                msg = advice_commit_before_merge
                      ? _("Your local changes to the following files would be overwritten by checkout:\n%%s"
@@ -118,7 +122,7 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
                          "Please commit your changes or stash them before you %s.")
                      : _("Your local changes to the following files would be overwritten by %s:\n%%s");
        msgs[ERROR_WOULD_OVERWRITE] = msgs[ERROR_NOT_UPTODATE_FILE] =
-               xstrfmt(msg, cmd, cmd);
+               argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
 
        msgs[ERROR_NOT_UPTODATE_DIR] =
                _("Updating the following directories would lose untracked files in them:\n%s");
@@ -138,7 +142,8 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
                      ? _("The following untracked working tree files would be removed by %s:\n%%s"
                          "Please move or remove them before you %s.")
                      : _("The following untracked working tree files would be removed by %s:\n%%s");
-       msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] = xstrfmt(msg, cmd, cmd);
+       msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] =
+               argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
 
        if (!strcmp(cmd, "checkout"))
                msg = advice_commit_before_merge
@@ -155,7 +160,8 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
                      ? _("The following untracked working tree files would be overwritten by %s:\n%%s"
                          "Please move or remove them before you %s.")
                      : _("The following untracked working tree files would be overwritten by %s:\n%%s");
-       msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] = xstrfmt(msg, cmd, cmd);
+       msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] =
+               argv_array_pushf(&opts->msgs_to_free, msg, cmd, cmd);
 
        /*
         * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
@@ -178,6 +184,12 @@ void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
                opts->unpack_rejects[i].strdup_strings = 1;
 }
 
+void clear_unpack_trees_porcelain(struct unpack_trees_options *opts)
+{
+       argv_array_clear(&opts->msgs_to_free);
+       memset(opts->msgs, 0, sizeof(opts->msgs));
+}
+
 static int do_add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
                         unsigned int set, unsigned int clear)
 {
@@ -191,20 +203,11 @@ static int do_add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
                               ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
 }
 
-static struct cache_entry *dup_entry(const struct cache_entry *ce)
-{
-       unsigned int size = ce_size(ce);
-       struct cache_entry *new = xmalloc(size);
-
-       memcpy(new, ce, size);
-       return new;
-}
-
 static void add_entry(struct unpack_trees_options *o,
                      const struct cache_entry *ce,
                      unsigned int set, unsigned int clear)
 {
-       do_add_entry(o, dup_entry(ce), set, clear);
+       do_add_entry(o, dup_cache_entry(ce, &o->result), set, clear);
 }
 
 /*
@@ -289,8 +292,8 @@ static void load_gitmodules_file(struct index_state *index,
                if (!state && ce->ce_flags & CE_WT_REMOVE) {
                        repo_read_gitmodules(the_repository);
                } else if (state && (ce->ce_flags & CE_UPDATE)) {
-                       submodule_free();
-                       checkout_entry(ce, state, NULL);
+                       submodule_free(the_repository);
+                       checkout_entry(ce, state, NULL, NULL);
                        repo_read_gitmodules(the_repository);
                }
        }
@@ -332,24 +335,68 @@ static struct progress *get_progress(struct unpack_trees_options *o)
        return start_delayed_progress(_("Checking out files"), total);
 }
 
+static void setup_collided_checkout_detection(struct checkout *state,
+                                             struct index_state *index)
+{
+       int i;
+
+       state->clone = 1;
+       for (i = 0; i < index->cache_nr; i++)
+               index->cache[i]->ce_flags &= ~CE_MATCHED;
+}
+
+static void report_collided_checkout(struct index_state *index)
+{
+       struct string_list list = STRING_LIST_INIT_NODUP;
+       int i;
+
+       for (i = 0; i < index->cache_nr; i++) {
+               struct cache_entry *ce = index->cache[i];
+
+               if (!(ce->ce_flags & CE_MATCHED))
+                       continue;
+
+               string_list_append(&list, ce->name);
+               ce->ce_flags &= ~CE_MATCHED;
+       }
+
+       list.cmp = fspathcmp;
+       string_list_sort(&list);
+
+       if (list.nr) {
+               warning(_("the following paths have collided (e.g. case-sensitive paths\n"
+                         "on a case-insensitive filesystem) and only one from the same\n"
+                         "colliding group is in the working tree:\n"));
+
+               for (i = 0; i < list.nr; i++)
+                       fprintf(stderr, "  '%s'\n", list.items[i].string);
+       }
+
+       string_list_clear(&list, 0);
+}
+
 static int check_updates(struct unpack_trees_options *o)
 {
        unsigned cnt = 0;
        int errs = 0;
-       struct progress *progress = NULL;
+       struct progress *progress;
        struct index_state *index = &o->result;
        struct checkout state = CHECKOUT_INIT;
        int i;
 
+       trace_performance_enter();
        state.force = 1;
        state.quiet = 1;
        state.refresh_cache = 1;
        state.istate = index;
 
+       if (o->clone)
+               setup_collided_checkout_detection(&state, index);
+
        progress = get_progress(o);
 
        if (o->update)
-               git_attr_set_direction(GIT_ATTR_CHECKOUT, index);
+               git_attr_set_direction(GIT_ATTR_CHECKOUT);
 
        if (should_update_submodules() && o->update && !o->dry_run)
                load_gitmodules_file(index, NULL);
@@ -370,24 +417,51 @@ static int check_updates(struct unpack_trees_options *o)
                load_gitmodules_file(index, &state);
 
        enable_delayed_checkout(&state);
+       if (repository_format_partial_clone && o->update && !o->dry_run) {
+               /*
+                * Prefetch the objects that are to be checked out in the loop
+                * below.
+                */
+               struct oid_array to_fetch = OID_ARRAY_INIT;
+               int fetch_if_missing_store = fetch_if_missing;
+               fetch_if_missing = 0;
+               for (i = 0; i < index->cache_nr; i++) {
+                       struct cache_entry *ce = index->cache[i];
+                       if ((ce->ce_flags & CE_UPDATE) &&
+                           !S_ISGITLINK(ce->ce_mode)) {
+                               if (!has_object_file(&ce->oid))
+                                       oid_array_append(&to_fetch, &ce->oid);
+                       }
+               }
+               if (to_fetch.nr)
+                       fetch_objects(repository_format_partial_clone,
+                                     to_fetch.oid, to_fetch.nr);
+               fetch_if_missing = fetch_if_missing_store;
+               oid_array_clear(&to_fetch);
+       }
        for (i = 0; i < index->cache_nr; i++) {
                struct cache_entry *ce = index->cache[i];
 
                if (ce->ce_flags & CE_UPDATE) {
                        if (ce->ce_flags & CE_WT_REMOVE)
-                               die("BUG: both update and delete flags are set on %s",
+                               BUG("both update and delete flags are set on %s",
                                    ce->name);
                        display_progress(progress, ++cnt);
                        ce->ce_flags &= ~CE_UPDATE;
                        if (o->update && !o->dry_run) {
-                               errs |= checkout_entry(ce, &state, NULL);
+                               errs |= checkout_entry(ce, &state, NULL, NULL);
                        }
                }
        }
        stop_progress(&progress);
-       errs |= finish_delayed_checkout(&state);
+       errs |= finish_delayed_checkout(&state, NULL);
        if (o->update)
-               git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
+               git_attr_set_direction(GIT_ATTR_CHECKIN);
+
+       if (o->clone)
+               report_collided_checkout(index);
+
+       trace_performance_leave("check_updates");
        return errs != 0;
 }
 
@@ -604,7 +678,114 @@ static int switch_cache_bottom(struct traverse_info *info)
 
 static inline int are_same_oid(struct name_entry *name_j, struct name_entry *name_k)
 {
-       return name_j->oid && name_k->oid && !oidcmp(name_j->oid, name_k->oid);
+       return !is_null_oid(&name_j->oid) && !is_null_oid(&name_k->oid) && oideq(&name_j->oid, &name_k->oid);
+}
+
+static int all_trees_same_as_cache_tree(int n, unsigned long dirmask,
+                                       struct name_entry *names,
+                                       struct traverse_info *info)
+{
+       struct unpack_trees_options *o = info->data;
+       int i;
+
+       if (!o->merge || dirmask != ((1 << n) - 1))
+               return 0;
+
+       for (i = 1; i < n; i++)
+               if (!are_same_oid(names, names + i))
+                       return 0;
+
+       return cache_tree_matches_traversal(o->src_index->cache_tree, names, info);
+}
+
+static int index_pos_by_traverse_info(struct name_entry *names,
+                                     struct traverse_info *info)
+{
+       struct unpack_trees_options *o = info->data;
+       int len = traverse_path_len(info, names);
+       char *name = xmalloc(len + 1 /* slash */ + 1 /* NUL */);
+       int pos;
+
+       make_traverse_path(name, info, names);
+       name[len++] = '/';
+       name[len] = '\0';
+       pos = index_name_pos(o->src_index, name, len);
+       if (pos >= 0)
+               BUG("This is a directory and should not exist in index");
+       pos = -pos - 1;
+       if (!starts_with(o->src_index->cache[pos]->name, name) ||
+           (pos > 0 && starts_with(o->src_index->cache[pos-1]->name, name)))
+               BUG("pos must point at the first entry in this directory");
+       free(name);
+       return pos;
+}
+
+/*
+ * Fast path if we detect that all trees are the same as cache-tree at this
+ * path. We'll walk these trees in an iterative loop using cache-tree/index
+ * instead of ODB since we already know what these trees contain.
+ */
+static int traverse_by_cache_tree(int pos, int nr_entries, int nr_names,
+                                 struct name_entry *names,
+                                 struct traverse_info *info)
+{
+       struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
+       struct unpack_trees_options *o = info->data;
+       struct cache_entry *tree_ce = NULL;
+       int ce_len = 0;
+       int i, d;
+
+       if (!o->merge)
+               BUG("We need cache-tree to do this optimization");
+
+       /*
+        * Do what unpack_callback() and unpack_nondirectories() normally
+        * do. But we walk all paths in an iterative loop instead.
+        *
+        * D/F conflicts and higher stage entries are not a concern
+        * because cache-tree would be invalidated and we would never
+        * get here in the first place.
+        */
+       for (i = 0; i < nr_entries; i++) {
+               int new_ce_len, len, rc;
+
+               src[0] = o->src_index->cache[pos + i];
+
+               len = ce_namelen(src[0]);
+               new_ce_len = cache_entry_size(len);
+
+               if (new_ce_len > ce_len) {
+                       new_ce_len <<= 1;
+                       tree_ce = xrealloc(tree_ce, new_ce_len);
+                       memset(tree_ce, 0, new_ce_len);
+                       ce_len = new_ce_len;
+
+                       tree_ce->ce_flags = create_ce_flags(0);
+
+                       for (d = 1; d <= nr_names; d++)
+                               src[d] = tree_ce;
+               }
+
+               tree_ce->ce_mode = src[0]->ce_mode;
+               tree_ce->ce_namelen = len;
+               oidcpy(&tree_ce->oid, &src[0]->oid);
+               memcpy(tree_ce->name, src[0]->name, len + 1);
+
+               rc = call_unpack_fn((const struct cache_entry * const *)src, o);
+               if (rc < 0) {
+                       free(tree_ce);
+                       return rc;
+               }
+
+               mark_ce_used(src[0], o);
+       }
+       free(tree_ce);
+       if (o->debug_unpack)
+               printf("Unpacked %d entries from %s to %s using cache-tree\n",
+                      nr_entries,
+                      o->src_index->cache[pos]->name,
+                      o->src_index->cache[pos + nr_entries - 1]->name);
+       return 0;
 }
 
 static int traverse_trees_recursive(int n, unsigned long dirmask,
@@ -612,12 +793,33 @@ static int traverse_trees_recursive(int n, unsigned long dirmask,
                                    struct name_entry *names,
                                    struct traverse_info *info)
 {
+       struct unpack_trees_options *o = info->data;
        int i, ret, bottom;
        int nr_buf = 0;
        struct tree_desc t[MAX_UNPACK_TREES];
        void *buf[MAX_UNPACK_TREES];
        struct traverse_info newinfo;
        struct name_entry *p;
+       int nr_entries;
+
+       nr_entries = all_trees_same_as_cache_tree(n, dirmask, names, info);
+       if (nr_entries > 0) {
+               int pos = index_pos_by_traverse_info(names, info);
+
+               if (!o->merge || df_conflicts)
+                       BUG("Wrong condition to get here buddy");
+
+               /*
+                * All entries up to 'pos' must have been processed
+                * (i.e. marked CE_UNPACKED) at this point. But to be safe,
+                * save and restore cache_bottom anyway to not miss
+                * unprocessed entries before 'pos'.
+                */
+               bottom = o->cache_bottom;
+               ret = traverse_by_cache_tree(pos, nr_entries, n, names, info);
+               o->cache_bottom = bottom;
+               return ret;
+       }
 
        p = names;
        while (!p->mode)
@@ -654,13 +856,13 @@ static int traverse_trees_recursive(int n, unsigned long dirmask,
                else {
                        const struct object_id *oid = NULL;
                        if (dirmask & 1)
-                               oid = names[i].oid;
+                               oid = &names[i].oid;
                        buf[nr_buf++] = fill_tree_descriptor(t + i, oid);
                }
        }
 
        bottom = switch_cache_bottom(&newinfo);
-       ret = traverse_trees(n, t, &newinfo);
+       ret = traverse_trees(o->src_index, n, t, &newinfo);
        restore_cache_bottom(&newinfo, bottom);
 
        for (i = 0; i < nr_buf; i++)
@@ -763,20 +965,32 @@ static int ce_in_traverse_path(const struct cache_entry *ce,
        return (info->pathlen < ce_namelen(ce));
 }
 
-static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
+static struct cache_entry *create_ce_entry(const struct traverse_info *info,
+       const struct name_entry *n,
+       int stage,
+       struct index_state *istate,
+       int is_transient)
 {
        int len = traverse_path_len(info, n);
-       struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
+       struct cache_entry *ce =
+               is_transient ?
+               make_empty_transient_cache_entry(len) :
+               make_empty_cache_entry(istate, len);
 
        ce->ce_mode = create_ce_mode(n->mode);
        ce->ce_flags = create_ce_flags(stage);
        ce->ce_namelen = len;
-       oidcpy(&ce->oid, n->oid);
+       oidcpy(&ce->oid, &n->oid);
        make_traverse_path(ce->name, info, n);
 
        return ce;
 }
 
+/*
+ * Note that traverse_by_cache_tree() duplicates some logic in this function
+ * without actually calling it. If you change the logic here you may need to
+ * check and change there as well.
+ */
 static int unpack_nondirectories(int n, unsigned long mask,
                                 unsigned long dirmask,
                                 struct cache_entry **src,
@@ -812,7 +1026,15 @@ static int unpack_nondirectories(int n, unsigned long mask,
                        stage = 3;
                else
                        stage = 2;
-               src[i + o->merge] = create_ce_entry(info, names + i, stage);
+
+               /*
+                * If the merge bit is set, then the cache entries are
+                * discarded in the following block.  In this case,
+                * construct "transient" cache_entries, as they are
+                * not stored in the index.  otherwise construct the
+                * cache entry from the index aware logic.
+                */
+               src[i + o->merge] = create_ce_entry(info, names + i, stage, &o->result, o->merge);
        }
 
        if (o->merge) {
@@ -821,7 +1043,7 @@ static int unpack_nondirectories(int n, unsigned long mask,
                for (i = 0; i < n; i++) {
                        struct cache_entry *ce = src[i + o->merge];
                        if (ce != o->df_conflict_entry)
-                               free(ce);
+                               discard_cache_entry(ce);
                }
                return rc;
        }
@@ -961,6 +1183,11 @@ static void debug_unpack_callback(int n,
                debug_name_entry(i, names + i);
 }
 
+/*
+ * Note that traverse_by_cache_tree() duplicates some logic in this function
+ * without actually calling it. If you change the logic here you may need to
+ * check and change there as well.
+ */
 static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
 {
        struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
@@ -1051,13 +1278,15 @@ static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, str
        return mask;
 }
 
-static int clear_ce_flags_1(struct cache_entry **cache, int nr,
+static int clear_ce_flags_1(struct index_state *istate,
+                           struct cache_entry **cache, int nr,
                            struct strbuf *prefix,
                            int select_mask, int clear_mask,
                            struct exclude_list *el, int defval);
 
 /* Whole directory matching */
-static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
+static int clear_ce_flags_dir(struct index_state *istate,
+                             struct cache_entry **cache, int nr,
                              struct strbuf *prefix,
                              char *basename,
                              int select_mask, int clear_mask,
@@ -1066,7 +1295,7 @@ static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
        struct cache_entry **cache_end;
        int dtype = DT_DIR;
        int ret = is_excluded_from_list(prefix->buf, prefix->len,
-                                       basename, &dtype, el, &the_index);
+                                       basename, &dtype, el, istate);
        int rc;
 
        strbuf_addch(prefix, '/');
@@ -1088,7 +1317,7 @@ static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
         * calling clear_ce_flags_1(). That function will call
         * the expensive is_excluded_from_list() on every entry.
         */
-       rc = clear_ce_flags_1(cache, cache_end - cache,
+       rc = clear_ce_flags_1(istate, cache, cache_end - cache,
                              prefix,
                              select_mask, clear_mask,
                              el, ret);
@@ -1111,7 +1340,8 @@ static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
  *   cache[0]->name[0..(prefix_len-1)]
  * Top level path has prefix_len zero.
  */
-static int clear_ce_flags_1(struct cache_entry **cache, int nr,
+static int clear_ce_flags_1(struct index_state *istate,
+                           struct cache_entry **cache, int nr,
                            struct strbuf *prefix,
                            int select_mask, int clear_mask,
                            struct exclude_list *el, int defval)
@@ -1145,7 +1375,7 @@ static int clear_ce_flags_1(struct cache_entry **cache, int nr,
                        len = slash - name;
                        strbuf_add(prefix, name, len);
 
-                       processed = clear_ce_flags_dir(cache, cache_end - cache,
+                       processed = clear_ce_flags_dir(istate, cache, cache_end - cache,
                                                       prefix,
                                                       prefix->buf + prefix->len - len,
                                                       select_mask, clear_mask,
@@ -1159,7 +1389,7 @@ static int clear_ce_flags_1(struct cache_entry **cache, int nr,
                        }
 
                        strbuf_addch(prefix, '/');
-                       cache += clear_ce_flags_1(cache, cache_end - cache,
+                       cache += clear_ce_flags_1(istate, cache, cache_end - cache,
                                                  prefix,
                                                  select_mask, clear_mask, el, defval);
                        strbuf_setlen(prefix, prefix->len - len - 1);
@@ -1169,7 +1399,7 @@ static int clear_ce_flags_1(struct cache_entry **cache, int nr,
                /* Non-directory */
                dtype = ce_to_dtype(ce);
                ret = is_excluded_from_list(ce->name, ce_namelen(ce),
-                                           name, &dtype, el, &the_index);
+                                           name, &dtype, el, istate);
                if (ret < 0)
                        ret = defval;
                if (ret > 0)
@@ -1179,15 +1409,17 @@ static int clear_ce_flags_1(struct cache_entry **cache, int nr,
        return nr - (cache_end - cache);
 }
 
-static int clear_ce_flags(struct cache_entry **cache, int nr,
-                           int select_mask, int clear_mask,
-                           struct exclude_list *el)
+static int clear_ce_flags(struct index_state *istate,
+                         int select_mask, int clear_mask,
+                         struct exclude_list *el)
 {
        static struct strbuf prefix = STRBUF_INIT;
 
        strbuf_reset(&prefix);
 
-       return clear_ce_flags_1(cache, nr,
+       return clear_ce_flags_1(istate,
+                               istate->cache,
+                               istate->cache_nr,
                                &prefix,
                                select_mask, clear_mask,
                                el, 0);
@@ -1197,7 +1429,7 @@ static int clear_ce_flags(struct cache_entry **cache, int nr,
  * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
  */
 static void mark_new_skip_worktree(struct exclude_list *el,
-                                  struct index_state *the_index,
+                                  struct index_state *istate,
                                   int select_flag, int skip_wt_flag)
 {
        int i;
@@ -1206,13 +1438,13 @@ static void mark_new_skip_worktree(struct exclude_list *el,
         * 1. Pretend the narrowest worktree: only unmerged entries
         * are checked out
         */
-       for (i = 0; i < the_index->cache_nr; i++) {
-               struct cache_entry *ce = the_index->cache[i];
+       for (i = 0; i < istate->cache_nr; i++) {
+               struct cache_entry *ce = istate->cache[i];
 
                if (select_flag && !(ce->ce_flags & select_flag))
                        continue;
 
-               if (!ce_stage(ce))
+               if (!ce_stage(ce) && !(ce->ce_flags & CE_CONFLICTED))
                        ce->ce_flags |= skip_wt_flag;
                else
                        ce->ce_flags &= ~skip_wt_flag;
@@ -1222,8 +1454,7 @@ static void mark_new_skip_worktree(struct exclude_list *el,
         * 2. Widen worktree according to sparse-checkout file.
         * Matched entries will have skip_wt_flag cleared (i.e. "in")
         */
-       clear_ce_flags(the_index->cache, the_index->cache_nr,
-                      select_flag, skip_wt_flag, el);
+       clear_ce_flags(istate, select_flag, skip_wt_flag, el);
 }
 
 static int verify_absent(const struct cache_entry *,
@@ -1244,6 +1475,7 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
        if (len > MAX_UNPACK_TREES)
                die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
 
+       trace_performance_enter();
        memset(&el, 0, sizeof(el));
        if (!core_apply_sparse_checkout || !o->update)
                o->skip_sparse_checkout = 1;
@@ -1261,10 +1493,21 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
        o->result.timestamp.sec = o->src_index->timestamp.sec;
        o->result.timestamp.nsec = o->src_index->timestamp.nsec;
        o->result.version = o->src_index->version;
-       o->result.split_index = o->src_index->split_index;
-       if (o->result.split_index)
+       if (!o->src_index->split_index) {
+               o->result.split_index = NULL;
+       } else if (o->src_index == o->dst_index) {
+               /*
+                * o->dst_index (and thus o->src_index) will be discarded
+                * and overwritten with o->result at the end of this function,
+                * so just use src_index's split_index to avoid having to
+                * create a new one.
+                */
+               o->result.split_index = o->src_index->split_index;
                o->result.split_index->refcount++;
-       hashcpy(o->result.sha1, o->src_index->sha1);
+       } else {
+               o->result.split_index = init_split_index(&o->result);
+       }
+       oidcpy(&o->result.oid, &o->src_index->oid);
        o->merge_size = len;
        mark_all_ce_unused(o->src_index);
 
@@ -1305,7 +1548,10 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
                        }
                }
 
-               if (traverse_trees(len, t, &info) < 0)
+               trace_performance_enter();
+               ret = traverse_trees(o->src_index, len, t, &info);
+               trace_performance_leave("traverse_trees");
+               if (ret < 0)
                        goto return_failed;
        }
 
@@ -1378,10 +1624,12 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
                }
        }
 
-       o->src_index = NULL;
        ret = check_updates(o) ? (-2) : 0;
        if (o->dst_index) {
+               move_index_extensions(&o->result, o->src_index);
                if (!ret) {
+                       if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0))
+                               cache_tree_verify(the_repository, &o->result);
                        if (!o->result.cache_tree)
                                o->result.cache_tree = cache_tree();
                        if (!cache_tree_fully_valid(o->result.cache_tree))
@@ -1389,14 +1637,15 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
                                                  WRITE_TREE_SILENT |
                                                  WRITE_TREE_REPAIR);
                }
-               move_index_extensions(&o->result, o->dst_index);
                discard_index(o->dst_index);
                *o->dst_index = o->result;
        } else {
                discard_index(&o->result);
        }
+       o->src_index = NULL;
 
 done:
+       trace_performance_leave("unpack_trees");
        clear_exclude_list(&el);
        return ret;
 
@@ -1428,7 +1677,7 @@ static int same(const struct cache_entry *a, const struct cache_entry *b)
        if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
                return 0;
        return a->ce_mode == b->ce_mode &&
-              !oidcmp(&a->oid, &b->oid);
+              oideq(&a->oid, &b->oid);
 }
 
 
@@ -1486,8 +1735,8 @@ static int verify_uptodate_1(const struct cache_entry *ce,
                add_rejected_path(o, error_type, ce->name);
 }
 
-static int verify_uptodate(const struct cache_entry *ce,
-                          struct unpack_trees_options *o)
+int verify_uptodate(const struct cache_entry *ce,
+                   struct unpack_trees_options *o)
 {
        if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
                return 0;
@@ -1500,13 +1749,24 @@ static int verify_uptodate_sparse(const struct cache_entry *ce,
        return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
 }
 
+/*
+ * TODO: We should actually invalidate o->result, not src_index [1].
+ * But since cache tree and untracked cache both are not copied to
+ * o->result until unpacking is complete, we invalidate them on
+ * src_index instead with the assumption that they will be copied to
+ * dst_index at the end.
+ *
+ * [1] src_index->cache_tree is also used in unpack_callback() so if
+ * we invalidate o->result, we need to update it to use
+ * o->result.cache_tree as well.
+ */
 static void invalidate_ce_path(const struct cache_entry *ce,
                               struct unpack_trees_options *o)
 {
        if (!ce)
                return;
        cache_tree_invalidate_path(o->src_index, ce->name);
-       untracked_cache_invalidate_path(o->src_index, ce->name);
+       untracked_cache_invalidate_path(o->src_index, ce->name, 1);
 }
 
 /*
@@ -1549,7 +1809,7 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
                 * If we are not going to update the submodule, then
                 * we don't care.
                 */
-               if (!sub_head && !oidcmp(&oid, &ce->oid))
+               if (!sub_head && oideq(&oid, &ce->oid))
                        return 0;
                return verify_clean_submodule(sub_head ? NULL : oid_to_hex(&oid),
                                              ce, error_type, o);
@@ -1577,6 +1837,7 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
                        if (verify_uptodate(ce2, o))
                                return -1;
                        add_entry(o, ce2, CE_REMOVE, 0);
+                       invalidate_ce_path(ce, o);
                        mark_ce_used(ce2, o);
                }
                cnt++;
@@ -1591,7 +1852,7 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
        memset(&d, 0, sizeof(d));
        if (o->dir)
                d.exclude_per_dir = o->dir->exclude_per_dir;
-       i = read_directory(&d, &the_index, pathbuf, namelen+1, NULL);
+       i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
        if (i)
                return o->gently ? -1 :
                        add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
@@ -1633,7 +1894,7 @@ static int check_ok_to_remove(const char *name, int len, int dtype,
                return 0;
 
        if (o->dir &&
-           is_excluded(o->dir, &the_index, name, &dtype))
+           is_excluded(o->dir, o->src_index, name, &dtype))
                /*
                 * ce->name is explicitly excluded, so it is Ok to
                 * overwrite it.
@@ -1742,7 +2003,7 @@ static int merged_entry(const struct cache_entry *ce,
                        struct unpack_trees_options *o)
 {
        int update = CE_UPDATE;
-       struct cache_entry *merge = dup_entry(ce);
+       struct cache_entry *merge = dup_cache_entry(ce, &o->result);
 
        if (!old) {
                /*
@@ -1762,7 +2023,7 @@ static int merged_entry(const struct cache_entry *ce,
 
                if (verify_absent(merge,
                                  ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
-                       free(merge);
+                       discard_cache_entry(merge);
                        return -1;
                }
                invalidate_ce_path(merge, o);
@@ -1788,7 +2049,7 @@ static int merged_entry(const struct cache_entry *ce,
                        update = 0;
                } else {
                        if (verify_uptodate(old, o)) {
-                               free(merge);
+                               discard_cache_entry(merge);
                                return -1;
                        }
                        /* Migrate old flags over */
@@ -1811,8 +2072,7 @@ static int merged_entry(const struct cache_entry *ce,
                invalidate_ce_path(old, o);
        }
 
-       if (do_add_entry(o, merge, update, CE_STAGEMASK) < 0)
-               return -1;
+       do_add_entry(o, merge, update, CE_STAGEMASK);
        return 1;
 }
 
@@ -1837,6 +2097,8 @@ static int keep_entry(const struct cache_entry *ce,
                      struct unpack_trees_options *o)
 {
        add_entry(o, ce, 0, 0);
+       if (ce_stage(ce))
+               invalidate_ce_path(ce, o);
        return 1;
 }