]> git.ipfire.org Git - thirdparty/git.git/blobdiff - dir.c
Sync with maint
[thirdparty/git.git] / dir.c
diff --git a/dir.c b/dir.c
index 9987011da57bcf171ba645788b8ccd2151561e5c..7d255227b130d7729747fe1a86c8efc04eee9f7e 100644 (file)
--- a/dir.c
+++ b/dir.c
@@ -2,15 +2,13 @@
  * This handles recursive filename detection with exclude
  * files, index knowledge etc..
  *
- * See Documentation/technical/api-directory-listing.txt
- *
  * Copyright (C) Linus Torvalds, 2005-2006
  *              Junio Hamano, 2005-2006
  */
-#define NO_THE_INDEX_COMPATIBILITY_MACROS
 #include "cache.h"
 #include "config.h"
 #include "dir.h"
+#include "object-store.h"
 #include "attr.h"
 #include "refs.h"
 #include "wildmatch.h"
@@ -18,6 +16,8 @@
 #include "utf8.h"
 #include "varint.h"
 #include "ewah/ewok.h"
+#include "fsmonitor.h"
+#include "submodule-config.h"
 
 /*
  * Tells read_directory_recursive how a file or directory should be treated.
@@ -137,7 +137,7 @@ static size_t common_prefix_len(const struct pathspec *pathspec)
         * ":(icase)path" is treated as a pathspec full of
         * wildcard. In other words, only prefix is considered common
         * prefix. If the pathspec is abc/foo abc/bar, running in
-        * subdir xyz, the common prefix is still xyz, not xuz/abc as
+        * subdir xyz, the common prefix is still xyz, not xyz/abc as
         * in non-:(icase).
         */
        GUARD_PATHSPEC(pathspec,
@@ -220,53 +220,84 @@ int within_depth(const char *name, int namelen,
        return 1;
 }
 
-#define DO_MATCH_EXCLUDE   (1<<0)
-#define DO_MATCH_DIRECTORY (1<<1)
-#define DO_MATCH_SUBMODULE (1<<2)
-
-static int match_attrs(const char *name, int namelen,
-                      const struct pathspec_item *item)
+/*
+ * Read the contents of the blob with the given OID into a buffer.
+ * Append a trailing LF to the end if the last line doesn't have one.
+ *
+ * Returns:
+ *    -1 when the OID is invalid or unknown or does not refer to a blob.
+ *     0 when the blob is empty.
+ *     1 along with { data, size } of the (possibly augmented) buffer
+ *       when successful.
+ *
+ * Optionally updates the given oid_stat with the given OID (when valid).
+ */
+static int do_read_blob(const struct object_id *oid, struct oid_stat *oid_stat,
+                       size_t *size_out, char **data_out)
 {
-       int i;
+       enum object_type type;
+       unsigned long sz;
+       char *data;
 
-       git_check_attr(name, item->attr_check);
-       for (i = 0; i < item->attr_match_nr; i++) {
-               const char *value;
-               int matched;
-               enum attr_match_mode match_mode;
-
-               value = item->attr_check->items[i].value;
-               match_mode = item->attr_match[i].match_mode;
-
-               if (ATTR_TRUE(value))
-                       matched = (match_mode == MATCH_SET);
-               else if (ATTR_FALSE(value))
-                       matched = (match_mode == MATCH_UNSET);
-               else if (ATTR_UNSET(value))
-                       matched = (match_mode == MATCH_UNSPECIFIED);
-               else
-                       matched = (match_mode == MATCH_VALUE &&
-                                  !strcmp(item->attr_match[i].value, value));
-               if (!matched)
-                       return 0;
+       *size_out = 0;
+       *data_out = NULL;
+
+       data = read_object_file(oid, &type, &sz);
+       if (!data || type != OBJ_BLOB) {
+               free(data);
+               return -1;
+       }
+
+       if (oid_stat) {
+               memset(&oid_stat->stat, 0, sizeof(oid_stat->stat));
+               oidcpy(&oid_stat->oid, oid);
+       }
+
+       if (sz == 0) {
+               free(data);
+               return 0;
+       }
+
+       if (data[sz - 1] != '\n') {
+               data = xrealloc(data, st_add(sz, 1));
+               data[sz++] = '\n';
        }
 
+       *size_out = xsize_t(sz);
+       *data_out = data;
+
        return 1;
 }
 
+#define DO_MATCH_EXCLUDE   (1<<0)
+#define DO_MATCH_DIRECTORY (1<<1)
+#define DO_MATCH_LEADING_PATHSPEC (1<<2)
+
 /*
- * Does 'match' match the given name?
- * A match is found if
+ * Does the given pathspec match the given name?  A match is found if
+ *
+ * (1) the pathspec string is leading directory of 'name' ("RECURSIVELY"), or
+ * (2) the pathspec string has a leading part matching 'name' ("LEADING"), or
+ * (3) the pathspec string is a wildcard and matches 'name' ("WILDCARD"), or
+ * (4) the pathspec string is exactly the same as 'name' ("EXACT").
  *
- * (1) the 'match' string is leading directory of 'name', or
- * (2) the 'match' string is a wildcard and matches 'name', or
- * (3) the 'match' string is exactly the same as 'name'.
+ * Return value tells which case it was (1-4), or 0 when there is no match.
  *
- * and the return value tells which case it was.
+ * It may be instructive to look at a small table of concrete examples
+ * to understand the differences between 1, 2, and 4:
  *
- * It returns 0 when there is no match.
+ *                              Pathspecs
+ *                |    a/b    |   a/b/    |   a/b/c
+ *          ------+-----------+-----------+------------
+ *          a/b   |  EXACT    |  EXACT[1] | LEADING[2]
+ *  Names   a/b/  | RECURSIVE |   EXACT   | LEADING[2]
+ *          a/b/c | RECURSIVE | RECURSIVE |   EXACT
+ *
+ * [1] Only if DO_MATCH_DIRECTORY is passed; otherwise, this is NOT a match.
+ * [2] Only if DO_MATCH_LEADING_PATHSPEC is passed; otherwise, not a match.
  */
-static int match_pathspec_item(const struct pathspec_item *item, int prefix,
+static int match_pathspec_item(const struct index_state *istate,
+                              const struct pathspec_item *item, int prefix,
                               const char *name, int namelen, unsigned flags)
 {
        /* name/namelen has prefix cut off by caller */
@@ -306,7 +337,8 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
            strncmp(item->match, name - prefix, item->prefix))
                return 0;
 
-       if (item->attr_match_nr && !match_attrs(name, namelen, item))
+       if (item->attr_match_nr &&
+           !match_pathspec_attrs(istate, name, namelen, item))
                return 0;
 
        /* If the match was just the prefix, we matched */
@@ -330,20 +362,28 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
                         item->nowildcard_len - prefix))
                return MATCHED_FNMATCH;
 
-       /* Perform checks to see if "name" is a super set of the pathspec */
-       if (flags & DO_MATCH_SUBMODULE) {
+       /* Perform checks to see if "name" is a leading string of the pathspec */
+       if (flags & DO_MATCH_LEADING_PATHSPEC) {
                /* name is a literal prefix of the pathspec */
+               int offset = name[namelen-1] == '/' ? 1 : 0;
                if ((namelen < matchlen) &&
-                   (match[namelen] == '/') &&
+                   (match[namelen-offset] == '/') &&
                    !ps_strncmp(item, match, name, namelen))
-                       return MATCHED_RECURSIVELY;
+                       return MATCHED_RECURSIVELY_LEADING_PATHSPEC;
 
-               /* name" doesn't match up to the first wild character */
+               /* name doesn't match up to the first wild character */
                if (item->nowildcard_len < item->len &&
                    ps_strncmp(item, match, name,
                               item->nowildcard_len - prefix))
                        return 0;
 
+               /*
+                * name has no wildcard, and it didn't match as a leading
+                * pathspec so return.
+                */
+               if (item->nowildcard_len == item->len)
+                       return 0;
+
                /*
                 * Here is where we would perform a wildmatch to check if
                 * "name" can be matched as a directory (or a prefix) against
@@ -353,7 +393,7 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
                 * The submodules themselves will be able to perform more
                 * accurate matching to determine if the pathspec matches.
                 */
-               return MATCHED_RECURSIVELY;
+               return MATCHED_RECURSIVELY_LEADING_PATHSPEC;
        }
 
        return 0;
@@ -374,7 +414,8 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
  * pathspec did not match any names, which could indicate that the
  * user mistyped the nth pathspec.
  */
-static int do_match_pathspec(const struct pathspec *ps,
+static int do_match_pathspec(const struct index_state *istate,
+                            const struct pathspec *ps,
                             const char *name, int namelen,
                             int prefix, char *seen,
                             unsigned flags)
@@ -420,7 +461,7 @@ static int do_match_pathspec(const struct pathspec *ps,
                 */
                if (seen && ps->items[i].magic & PATHSPEC_EXCLUDE)
                        seen[i] = MATCHED_FNMATCH;
-               how = match_pathspec_item(ps->items+i, prefix, name,
+               how = match_pathspec_item(istate, ps->items+i, prefix, name,
                                          namelen, flags);
                if (ps->recursive &&
                    (ps->magic & PATHSPEC_MAXDEPTH) &&
@@ -444,17 +485,18 @@ static int do_match_pathspec(const struct pathspec *ps,
        return retval;
 }
 
-int match_pathspec(const struct pathspec *ps,
+int match_pathspec(const struct index_state *istate,
+                  const struct pathspec *ps,
                   const char *name, int namelen,
                   int prefix, char *seen, int is_dir)
 {
        int positive, negative;
        unsigned flags = is_dir ? DO_MATCH_DIRECTORY : 0;
-       positive = do_match_pathspec(ps, name, namelen,
+       positive = do_match_pathspec(istate, ps, name, namelen,
                                     prefix, seen, flags);
        if (!(ps->magic & PATHSPEC_EXCLUDE) || !positive)
                return positive;
-       negative = do_match_pathspec(ps, name, namelen,
+       negative = do_match_pathspec(istate, ps, name, namelen,
                                     prefix, seen,
                                     flags | DO_MATCH_EXCLUDE);
        return negative ? 0 : positive;
@@ -463,21 +505,21 @@ int match_pathspec(const struct pathspec *ps,
 /**
  * Check if a submodule is a superset of the pathspec
  */
-int submodule_path_match(const struct pathspec *ps,
+int submodule_path_match(const struct index_state *istate,
+                        const struct pathspec *ps,
                         const char *submodule_name,
                         char *seen)
 {
-       int matched = do_match_pathspec(ps, submodule_name,
+       int matched = do_match_pathspec(istate, ps, submodule_name,
                                        strlen(submodule_name),
                                        0, seen,
                                        DO_MATCH_DIRECTORY |
-                                       DO_MATCH_SUBMODULE);
+                                       DO_MATCH_LEADING_PATHSPEC);
        return matched;
 }
 
 int report_path_error(const char *ps_matched,
-                     const struct pathspec *pathspec,
-                     const char *prefix)
+                     const struct pathspec *pathspec)
 {
        /*
         * Make sure all pathspec matched; otherwise it is an error.
@@ -509,7 +551,7 @@ int report_path_error(const char *ps_matched,
                if (found_dup)
                        continue;
 
-               error("pathspec '%s' did not match any file(s) known to git.",
+               error(_("pathspec '%s' did not match any file(s) known to git"),
                      pathspec->items[num].original);
                errors++;
        }
@@ -536,7 +578,7 @@ int no_wildcard(const char *string)
        return string[simple_length(string)] == '\0';
 }
 
-void parse_exclude_pattern(const char **pattern,
+void parse_path_pattern(const char **pattern,
                           int *patternlen,
                           unsigned *flags,
                           int *nowildcardlen)
@@ -546,20 +588,20 @@ void parse_exclude_pattern(const char **pattern,
 
        *flags = 0;
        if (*p == '!') {
-               *flags |= EXC_FLAG_NEGATIVE;
+               *flags |= PATTERN_FLAG_NEGATIVE;
                p++;
        }
        len = strlen(p);
        if (len && p[len - 1] == '/') {
                len--;
-               *flags |= EXC_FLAG_MUSTBEDIR;
+               *flags |= PATTERN_FLAG_MUSTBEDIR;
        }
        for (i = 0; i < len; i++) {
                if (p[i] == '/')
                        break;
        }
        if (i == len)
-               *flags |= EXC_FLAG_NODIR;
+               *flags |= PATTERN_FLAG_NODIR;
        *nowildcardlen = simple_length(p);
        /*
         * we should have excluded the trailing slash from 'p' too,
@@ -569,79 +611,223 @@ void parse_exclude_pattern(const char **pattern,
        if (*nowildcardlen > len)
                *nowildcardlen = len;
        if (*p == '*' && no_wildcard(p + 1))
-               *flags |= EXC_FLAG_ENDSWITH;
+               *flags |= PATTERN_FLAG_ENDSWITH;
        *pattern = p;
        *patternlen = len;
 }
 
-void add_exclude(const char *string, const char *base,
-                int baselen, struct exclude_list *el, int srcpos)
+int pl_hashmap_cmp(const void *unused_cmp_data,
+                  const struct hashmap_entry *a,
+                  const struct hashmap_entry *b,
+                  const void *key)
+{
+       const struct pattern_entry *ee1 =
+                       container_of(a, struct pattern_entry, ent);
+       const struct pattern_entry *ee2 =
+                       container_of(b, struct pattern_entry, ent);
+
+       size_t min_len = ee1->patternlen <= ee2->patternlen
+                        ? ee1->patternlen
+                        : ee2->patternlen;
+
+       if (ignore_case)
+               return strncasecmp(ee1->pattern, ee2->pattern, min_len);
+       return strncmp(ee1->pattern, ee2->pattern, min_len);
+}
+
+static void add_pattern_to_hashsets(struct pattern_list *pl, struct path_pattern *given)
 {
-       struct exclude *x;
+       struct pattern_entry *translated;
+       char *truncated;
+       char *data = NULL;
+
+       if (!pl->use_cone_patterns)
+               return;
+
+       if (given->flags & PATTERN_FLAG_NEGATIVE &&
+           given->flags & PATTERN_FLAG_MUSTBEDIR &&
+           !strcmp(given->pattern, "/*")) {
+               pl->full_cone = 0;
+               return;
+       }
+
+       if (!given->flags && !strcmp(given->pattern, "/*")) {
+               pl->full_cone = 1;
+               return;
+       }
+
+       if (given->patternlen > 2 &&
+           !strcmp(given->pattern + given->patternlen - 2, "/*")) {
+               if (!(given->flags & PATTERN_FLAG_NEGATIVE)) {
+                       /* Not a cone pattern. */
+                       pl->use_cone_patterns = 0;
+                       warning(_("unrecognized pattern: '%s'"), given->pattern);
+                       goto clear_hashmaps;
+               }
+
+               truncated = xstrdup(given->pattern);
+               truncated[given->patternlen - 2] = 0;
+
+               translated = xmalloc(sizeof(struct pattern_entry));
+               translated->pattern = truncated;
+               translated->patternlen = given->patternlen - 2;
+               hashmap_entry_init(&translated->ent,
+                                  ignore_case ?
+                                  strihash(translated->pattern) :
+                                  strhash(translated->pattern));
+
+               if (!hashmap_get_entry(&pl->recursive_hashmap,
+                                      translated, ent, NULL)) {
+                       /* We did not see the "parent" included */
+                       warning(_("unrecognized negative pattern: '%s'"),
+                               given->pattern);
+                       free(truncated);
+                       free(translated);
+                       goto clear_hashmaps;
+               }
+
+               hashmap_add(&pl->parent_hashmap, &translated->ent);
+               hashmap_remove(&pl->recursive_hashmap, &translated->ent, &data);
+               free(data);
+               return;
+       }
+
+       if (given->flags & PATTERN_FLAG_NEGATIVE) {
+               warning(_("unrecognized negative pattern: '%s'"),
+                       given->pattern);
+               goto clear_hashmaps;
+       }
+
+       translated = xmalloc(sizeof(struct pattern_entry));
+
+       translated->pattern = xstrdup(given->pattern);
+       translated->patternlen = given->patternlen;
+       hashmap_entry_init(&translated->ent,
+                          ignore_case ?
+                          strihash(translated->pattern) :
+                          strhash(translated->pattern));
+
+       hashmap_add(&pl->recursive_hashmap, &translated->ent);
+
+       if (hashmap_get_entry(&pl->parent_hashmap, translated, ent, NULL)) {
+               /* we already included this at the parent level */
+               warning(_("your sparse-checkout file may have issues: pattern '%s' is repeated"),
+                       given->pattern);
+               hashmap_remove(&pl->parent_hashmap, &translated->ent, &data);
+               free(data);
+               free(translated);
+       }
+
+       return;
+
+clear_hashmaps:
+       warning(_("disabling cone pattern matching"));
+       hashmap_free_entries(&pl->parent_hashmap, struct pattern_entry, ent);
+       hashmap_free_entries(&pl->recursive_hashmap, struct pattern_entry, ent);
+       pl->use_cone_patterns = 0;
+}
+
+static int hashmap_contains_path(struct hashmap *map,
+                                struct strbuf *pattern)
+{
+       struct pattern_entry p;
+
+       /* Check straight mapping */
+       p.pattern = pattern->buf;
+       p.patternlen = pattern->len;
+       hashmap_entry_init(&p.ent,
+                          ignore_case ?
+                          strihash(p.pattern) :
+                          strhash(p.pattern));
+       return !!hashmap_get_entry(map, &p, ent, NULL);
+}
+
+int hashmap_contains_parent(struct hashmap *map,
+                           const char *path,
+                           struct strbuf *buffer)
+{
+       char *slash_pos;
+
+       strbuf_setlen(buffer, 0);
+
+       if (path[0] != '/')
+               strbuf_addch(buffer, '/');
+
+       strbuf_addstr(buffer, path);
+
+       slash_pos = strrchr(buffer->buf, '/');
+
+       while (slash_pos > buffer->buf) {
+               strbuf_setlen(buffer, slash_pos - buffer->buf);
+
+               if (hashmap_contains_path(map, buffer))
+                       return 1;
+
+               slash_pos = strrchr(buffer->buf, '/');
+       }
+
+       return 0;
+}
+
+void add_pattern(const char *string, const char *base,
+                int baselen, struct pattern_list *pl, int srcpos)
+{
+       struct path_pattern *pattern;
        int patternlen;
        unsigned flags;
        int nowildcardlen;
 
-       parse_exclude_pattern(&string, &patternlen, &flags, &nowildcardlen);
-       if (flags & EXC_FLAG_MUSTBEDIR) {
-               FLEXPTR_ALLOC_MEM(x, pattern, string, patternlen);
+       parse_path_pattern(&string, &patternlen, &flags, &nowildcardlen);
+       if (flags & PATTERN_FLAG_MUSTBEDIR) {
+               FLEXPTR_ALLOC_MEM(pattern, pattern, string, patternlen);
        } else {
-               x = xmalloc(sizeof(*x));
-               x->pattern = string;
+               pattern = xmalloc(sizeof(*pattern));
+               pattern->pattern = string;
        }
-       x->patternlen = patternlen;
-       x->nowildcardlen = nowildcardlen;
-       x->base = base;
-       x->baselen = baselen;
-       x->flags = flags;
-       x->srcpos = srcpos;
-       ALLOC_GROW(el->excludes, el->nr + 1, el->alloc);
-       el->excludes[el->nr++] = x;
-       x->el = el;
+       pattern->patternlen = patternlen;
+       pattern->nowildcardlen = nowildcardlen;
+       pattern->base = base;
+       pattern->baselen = baselen;
+       pattern->flags = flags;
+       pattern->srcpos = srcpos;
+       ALLOC_GROW(pl->patterns, pl->nr + 1, pl->alloc);
+       pl->patterns[pl->nr++] = pattern;
+       pattern->pl = pl;
+
+       add_pattern_to_hashsets(pl, pattern);
 }
 
-static void *read_skip_worktree_file_from_index(const struct index_state *istate,
-                                               const char *path, size_t *size,
-                                               struct sha1_stat *sha1_stat)
+static int read_skip_worktree_file_from_index(const struct index_state *istate,
+                                             const char *path,
+                                             size_t *size_out, char **data_out,
+                                             struct oid_stat *oid_stat)
 {
        int pos, len;
-       unsigned long sz;
-       enum object_type type;
-       void *data;
 
        len = strlen(path);
        pos = index_name_pos(istate, path, len);
        if (pos < 0)
-               return NULL;
+               return -1;
        if (!ce_skip_worktree(istate->cache[pos]))
-               return NULL;
-       data = read_sha1_file(istate->cache[pos]->oid.hash, &type, &sz);
-       if (!data || type != OBJ_BLOB) {
-               free(data);
-               return NULL;
-       }
-       *size = xsize_t(sz);
-       if (sha1_stat) {
-               memset(&sha1_stat->stat, 0, sizeof(sha1_stat->stat));
-               hashcpy(sha1_stat->sha1, istate->cache[pos]->oid.hash);
-       }
-       return data;
+               return -1;
+
+       return do_read_blob(&istate->cache[pos]->oid, oid_stat, size_out, data_out);
 }
 
 /*
- * Frees memory within el which was allocated for exclude patterns and
- * the file buffer.  Does not free el itself.
+ * Frees memory within pl which was allocated for exclude patterns and
+ * the file buffer.  Does not free pl itself.
  */
-void clear_exclude_list(struct exclude_list *el)
+void clear_pattern_list(struct pattern_list *pl)
 {
        int i;
 
-       for (i = 0; i < el->nr; i++)
-               free(el->excludes[i]);
-       free(el->excludes);
-       free(el->filebuf);
+       for (i = 0; i < pl->nr; i++)
+               free(pl->patterns[i]);
+       free(pl->patterns);
+       free(pl->filebuf);
 
-       memset(el, 0, sizeof(*el));
+       memset(pl, 0, sizeof(*pl));
 }
 
 static void trim_trailing_spaces(char *buf)
@@ -687,7 +873,7 @@ static struct untracked_cache_dir *lookup_untracked(struct untracked_cache *uc,
        first = 0;
        last = dir->dirs_nr;
        while (last > first) {
-               int cmp, next = (last + first) >> 1;
+               int cmp, next = first + ((last - first) >> 1);
                d = dir->dirs[next];
                cmp = strncmp(name, d->name, len);
                if (!cmp && strlen(d->name) > len)
@@ -705,8 +891,8 @@ static struct untracked_cache_dir *lookup_untracked(struct untracked_cache *uc,
        FLEX_ALLOC_MEM(d, name, name, len);
 
        ALLOC_GROW(dir->dirs, dir->dirs_nr + 1, dir->dirs_alloc);
-       memmove(dir->dirs + first + 1, dir->dirs + first,
-               (dir->dirs_nr - first) * sizeof(*dir->dirs));
+       MOVE_ARRAY(dir->dirs + first + 1, dir->dirs + first,
+                  dir->dirs_nr - first);
        dir->dirs_nr++;
        dir->dirs[first] = d;
        return d;
@@ -732,31 +918,44 @@ static void invalidate_directory(struct untracked_cache *uc,
                                 struct untracked_cache_dir *dir)
 {
        int i;
-       uc->dir_invalidated++;
+
+       /*
+        * Invalidation increment here is just roughly correct. If
+        * untracked_nr or any of dirs[].recurse is non-zero, we
+        * should increment dir_invalidated too. But that's more
+        * expensive to do.
+        */
+       if (dir->valid)
+               uc->dir_invalidated++;
+
        dir->valid = 0;
        dir->untracked_nr = 0;
        for (i = 0; i < dir->dirs_nr; i++)
                dir->dirs[i]->recurse = 0;
 }
 
+static int add_patterns_from_buffer(char *buf, size_t size,
+                                   const char *base, int baselen,
+                                   struct pattern_list *pl);
+
 /*
  * Given a file with name "fname", read it (either from disk, or from
  * an index if 'istate' is non-null), parse it and store the
- * exclude rules in "el".
+ * exclude rules in "pl".
  *
  * If "ss" is not NULL, compute SHA-1 of the exclude file and fill
- * stat data from disk (only valid if add_excludes returns zero). If
+ * stat data from disk (only valid if add_patterns returns zero). If
  * ss_valid is non-zero, "ss" must contain good value as input.
  */
-static int add_excludes(const char *fname, const char *base, int baselen,
-                       struct exclude_list *el,
-                       struct index_state *istate,
-                       struct sha1_stat *sha1_stat)
+static int add_patterns(const char *fname, const char *base, int baselen,
+                       struct pattern_list *pl, struct index_state *istate,
+                       struct oid_stat *oid_stat)
 {
        struct stat st;
-       int fd, i, lineno = 1;
+       int r;
+       int fd;
        size_t size = 0;
-       char *buf, *entry;
+       char *buf;
 
        fd = open(fname, O_RDONLY);
        if (fd < 0 || fstat(fd, &st) < 0) {
@@ -764,24 +963,20 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                        warn_on_fopen_errors(fname);
                else
                        close(fd);
-               if (!istate ||
-                   (buf = read_skip_worktree_file_from_index(istate, fname, &size, sha1_stat)) == NULL)
+               if (!istate)
                        return -1;
-               if (size == 0) {
-                       free(buf);
-                       return 0;
-               }
-               if (buf[size-1] != '\n') {
-                       buf = xrealloc(buf, st_add(size, 1));
-                       buf[size++] = '\n';
-               }
+               r = read_skip_worktree_file_from_index(istate, fname,
+                                                      &size, &buf,
+                                                      oid_stat);
+               if (r != 1)
+                       return r;
        } else {
                size = xsize_t(st.st_size);
                if (size == 0) {
-                       if (sha1_stat) {
-                               fill_stat_data(&sha1_stat->stat, &st);
-                               hashcpy(sha1_stat->sha1, EMPTY_BLOB_SHA1_BIN);
-                               sha1_stat->valid = 1;
+                       if (oid_stat) {
+                               fill_stat_data(&oid_stat->stat, &st);
+                               oidcpy(&oid_stat->oid, the_hash_algo->empty_blob);
+                               oid_stat->valid = 1;
                        }
                        close(fd);
                        return 0;
@@ -794,29 +989,44 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                }
                buf[size++] = '\n';
                close(fd);
-               if (sha1_stat) {
+               if (oid_stat) {
                        int pos;
-                       if (sha1_stat->valid &&
-                           !match_stat_data_racy(istate, &sha1_stat->stat, &st))
+                       if (oid_stat->valid &&
+                           !match_stat_data_racy(istate, &oid_stat->stat, &st))
                                ; /* no content change, ss->sha1 still good */
                        else if (istate &&
                                 (pos = index_name_pos(istate, fname, strlen(fname))) >= 0 &&
                                 !ce_stage(istate->cache[pos]) &&
                                 ce_uptodate(istate->cache[pos]) &&
                                 !would_convert_to_git(istate, fname))
-                               hashcpy(sha1_stat->sha1,
-                                       istate->cache[pos]->oid.hash);
+                               oidcpy(&oid_stat->oid,
+                                      &istate->cache[pos]->oid);
                        else
-                               hash_sha1_file(buf, size, "blob", sha1_stat->sha1);
-                       fill_stat_data(&sha1_stat->stat, &st);
-                       sha1_stat->valid = 1;
+                               hash_object_file(buf, size, "blob",
+                                                &oid_stat->oid);
+                       fill_stat_data(&oid_stat->stat, &st);
+                       oid_stat->valid = 1;
                }
        }
 
-       el->filebuf = buf;
+       add_patterns_from_buffer(buf, size, base, baselen, pl);
+       return 0;
+}
+
+static int add_patterns_from_buffer(char *buf, size_t size,
+                                   const char *base, int baselen,
+                                   struct pattern_list *pl)
+{
+       int i, lineno = 1;
+       char *entry;
+
+       hashmap_init(&pl->recursive_hashmap, pl_hashmap_cmp, NULL, 0);
+       hashmap_init(&pl->parent_hashmap, pl_hashmap_cmp, NULL, 0);
+
+       pl->filebuf = buf;
 
        if (skip_utf8_bom(&buf, size))
-               size -= buf - el->filebuf;
+               size -= buf - pl->filebuf;
 
        entry = buf;
 
@@ -825,7 +1035,7 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                        if (entry != buf + i && entry[0] != '#') {
                                buf[i - (i && buf[i-1] == '\r')] = 0;
                                trim_trailing_spaces(entry);
-                               add_exclude(entry, base, baselen, el, lineno);
+                               add_pattern(entry, base, baselen, pl, lineno);
                        }
                        lineno++;
                        entry = buf + i + 1;
@@ -834,34 +1044,51 @@ static int add_excludes(const char *fname, const char *base, int baselen,
        return 0;
 }
 
-int add_excludes_from_file_to_list(const char *fname, const char *base,
-                                  int baselen, struct exclude_list *el,
+int add_patterns_from_file_to_list(const char *fname, const char *base,
+                                  int baselen, struct pattern_list *pl,
                                   struct index_state *istate)
 {
-       return add_excludes(fname, base, baselen, el, istate, NULL);
+       return add_patterns(fname, base, baselen, pl, istate, NULL);
 }
 
-struct exclude_list *add_exclude_list(struct dir_struct *dir,
+int add_patterns_from_blob_to_list(
+       struct object_id *oid,
+       const char *base, int baselen,
+       struct pattern_list *pl)
+{
+       char *buf;
+       size_t size;
+       int r;
+
+       r = do_read_blob(oid, NULL, &size, &buf);
+       if (r != 1)
+               return r;
+
+       add_patterns_from_buffer(buf, size, base, baselen, pl);
+       return 0;
+}
+
+struct pattern_list *add_pattern_list(struct dir_struct *dir,
                                      int group_type, const char *src)
 {
-       struct exclude_list *el;
+       struct pattern_list *pl;
        struct exclude_list_group *group;
 
        group = &dir->exclude_list_group[group_type];
-       ALLOC_GROW(group->el, group->nr + 1, group->alloc);
-       el = &group->el[group->nr++];
-       memset(el, 0, sizeof(*el));
-       el->src = src;
-       return el;
+       ALLOC_GROW(group->pl, group->nr + 1, group->alloc);
+       pl = &group->pl[group->nr++];
+       memset(pl, 0, sizeof(*pl));
+       pl->src = src;
+       return pl;
 }
 
 /*
  * Used to set up core.excludesfile and .git/info/exclude lists.
  */
-static void add_excludes_from_file_1(struct dir_struct *dir, const char *fname,
-                                    struct sha1_stat *sha1_stat)
+static void add_patterns_from_file_1(struct dir_struct *dir, const char *fname,
+                                    struct oid_stat *oid_stat)
 {
-       struct exclude_list *el;
+       struct pattern_list *pl;
        /*
         * catch setup_standard_excludes() that's called before
         * dir->untracked is assigned. That function behaves
@@ -869,15 +1096,15 @@ static void add_excludes_from_file_1(struct dir_struct *dir, const char *fname,
         */
        if (!dir->untracked)
                dir->unmanaged_exclude_files++;
-       el = add_exclude_list(dir, EXC_FILE, fname);
-       if (add_excludes(fname, "", 0, el, NULL, sha1_stat) < 0)
-               die("cannot use %s as an exclude file", fname);
+       pl = add_pattern_list(dir, EXC_FILE, fname);
+       if (add_patterns(fname, "", 0, pl, NULL, oid_stat) < 0)
+               die(_("cannot use %s as an exclude file"), fname);
 }
 
-void add_excludes_from_file(struct dir_struct *dir, const char *fname)
+void add_patterns_from_file(struct dir_struct *dir, const char *fname)
 {
        dir->unmanaged_exclude_files++; /* see validate_untracked_cache() */
-       add_excludes_from_file_1(dir, fname, NULL);
+       add_patterns_from_file_1(dir, fname, NULL);
 }
 
 int match_basename(const char *basename, int basenamelen,
@@ -888,7 +1115,7 @@ int match_basename(const char *basename, int basenamelen,
                if (patternlen == basenamelen &&
                    !fspathncmp(pattern, basename, basenamelen))
                        return 1;
-       } else if (flags & EXC_FLAG_ENDSWITH) {
+       } else if (flags & PATTERN_FLAG_ENDSWITH) {
                /* "*literal" matching against "fooliteral" */
                if (patternlen - 1 <= basenamelen &&
                    !fspathncmp(pattern + 1,
@@ -969,85 +1196,139 @@ int match_pathname(const char *pathname, int pathlen,
  * any, determines the fate.  Returns the exclude_list element which
  * matched, or NULL for undecided.
  */
-static struct exclude *last_exclude_matching_from_list(const char *pathname,
+static struct path_pattern *last_matching_pattern_from_list(const char *pathname,
                                                       int pathlen,
                                                       const char *basename,
                                                       int *dtype,
-                                                      struct exclude_list *el,
+                                                      struct pattern_list *pl,
                                                       struct index_state *istate)
 {
-       struct exclude *exc = NULL; /* undecided */
+       struct path_pattern *res = NULL; /* undecided */
        int i;
 
-       if (!el->nr)
+       if (!pl->nr)
                return NULL;    /* undefined */
 
-       for (i = el->nr - 1; 0 <= i; i--) {
-               struct exclude *x = el->excludes[i];
-               const char *exclude = x->pattern;
-               int prefix = x->nowildcardlen;
+       for (i = pl->nr - 1; 0 <= i; i--) {
+               struct path_pattern *pattern = pl->patterns[i];
+               const char *exclude = pattern->pattern;
+               int prefix = pattern->nowildcardlen;
 
-               if (x->flags & EXC_FLAG_MUSTBEDIR) {
+               if (pattern->flags & PATTERN_FLAG_MUSTBEDIR) {
                        if (*dtype == DT_UNKNOWN)
                                *dtype = get_dtype(NULL, istate, pathname, pathlen);
                        if (*dtype != DT_DIR)
                                continue;
                }
 
-               if (x->flags & EXC_FLAG_NODIR) {
+               if (pattern->flags & PATTERN_FLAG_NODIR) {
                        if (match_basename(basename,
                                           pathlen - (basename - pathname),
-                                          exclude, prefix, x->patternlen,
-                                          x->flags)) {
-                               exc = x;
+                                          exclude, prefix, pattern->patternlen,
+                                          pattern->flags)) {
+                               res = pattern;
                                break;
                        }
                        continue;
                }
 
-               assert(x->baselen == 0 || x->base[x->baselen - 1] == '/');
+               assert(pattern->baselen == 0 ||
+                      pattern->base[pattern->baselen - 1] == '/');
                if (match_pathname(pathname, pathlen,
-                                  x->base, x->baselen ? x->baselen - 1 : 0,
-                                  exclude, prefix, x->patternlen, x->flags)) {
-                       exc = x;
+                                  pattern->base,
+                                  pattern->baselen ? pattern->baselen - 1 : 0,
+                                  exclude, prefix, pattern->patternlen,
+                                  pattern->flags)) {
+                       res = pattern;
                        break;
                }
        }
-       return exc;
+       return res;
 }
 
 /*
- * Scan the list and let the last match determine the fate.
- * Return 1 for exclude, 0 for include and -1 for undecided.
+ * Scan the list of patterns to determine if the ordered list
+ * of patterns matches on 'pathname'.
+ *
+ * Return 1 for a match, 0 for not matched and -1 for undecided.
  */
-int is_excluded_from_list(const char *pathname,
-                         int pathlen, const char *basename, int *dtype,
-                         struct exclude_list *el, struct index_state *istate)
-{
-       struct exclude *exclude;
-       exclude = last_exclude_matching_from_list(pathname, pathlen, basename,
-                                                 dtype, el, istate);
-       if (exclude)
-               return exclude->flags & EXC_FLAG_NEGATIVE ? 0 : 1;
-       return -1; /* undecided */
+enum pattern_match_result path_matches_pattern_list(
+                               const char *pathname, int pathlen,
+                               const char *basename, int *dtype,
+                               struct pattern_list *pl,
+                               struct index_state *istate)
+{
+       struct path_pattern *pattern;
+       struct strbuf parent_pathname = STRBUF_INIT;
+       int result = NOT_MATCHED;
+       const char *slash_pos;
+
+       if (!pl->use_cone_patterns) {
+               pattern = last_matching_pattern_from_list(pathname, pathlen, basename,
+                                                       dtype, pl, istate);
+               if (pattern) {
+                       if (pattern->flags & PATTERN_FLAG_NEGATIVE)
+                               return NOT_MATCHED;
+                       else
+                               return MATCHED;
+               }
+
+               return UNDECIDED;
+       }
+
+       if (pl->full_cone)
+               return MATCHED;
+
+       strbuf_addch(&parent_pathname, '/');
+       strbuf_add(&parent_pathname, pathname, pathlen);
+
+       if (hashmap_contains_path(&pl->recursive_hashmap,
+                                 &parent_pathname)) {
+               result = MATCHED_RECURSIVE;
+               goto done;
+       }
+
+       slash_pos = strrchr(parent_pathname.buf, '/');
+
+       if (slash_pos == parent_pathname.buf) {
+               /* include every file in root */
+               result = MATCHED;
+               goto done;
+       }
+
+       strbuf_setlen(&parent_pathname, slash_pos - parent_pathname.buf);
+
+       if (hashmap_contains_path(&pl->parent_hashmap, &parent_pathname)) {
+               result = MATCHED;
+               goto done;
+       }
+
+       if (hashmap_contains_parent(&pl->recursive_hashmap,
+                                   pathname,
+                                   &parent_pathname))
+               result = MATCHED_RECURSIVE;
+
+done:
+       strbuf_release(&parent_pathname);
+       return result;
 }
 
-static struct exclude *last_exclude_matching_from_lists(struct dir_struct *dir,
-                                                       struct index_state *istate,
-               const char *pathname, int pathlen, const char *basename,
-               int *dtype_p)
+static struct path_pattern *last_matching_pattern_from_lists(
+               struct dir_struct *dir, struct index_state *istate,
+               const char *pathname, int pathlen,
+               const char *basename, int *dtype_p)
 {
        int i, j;
        struct exclude_list_group *group;
-       struct exclude *exclude;
+       struct path_pattern *pattern;
        for (i = EXC_CMDL; i <= EXC_FILE; i++) {
                group = &dir->exclude_list_group[i];
                for (j = group->nr - 1; j >= 0; j--) {
-                       exclude = last_exclude_matching_from_list(
+                       pattern = last_matching_pattern_from_list(
                                pathname, pathlen, basename, dtype_p,
-                               &group->el[j], istate);
-                       if (exclude)
-                               return exclude;
+                               &group->pl[j], istate);
+                       if (pattern)
+                               return pattern;
                }
        }
        return NULL;
@@ -1062,7 +1343,7 @@ static void prep_exclude(struct dir_struct *dir,
                         const char *base, int baselen)
 {
        struct exclude_list_group *group;
-       struct exclude_list *el;
+       struct pattern_list *pl;
        struct exclude_stack *stk = NULL;
        struct untracked_cache_dir *untracked;
        int current;
@@ -1078,17 +1359,17 @@ static void prep_exclude(struct dir_struct *dir,
                if (stk->baselen <= baselen &&
                    !strncmp(dir->basebuf.buf, base, stk->baselen))
                        break;
-               el = &group->el[dir->exclude_stack->exclude_ix];
+               pl = &group->pl[dir->exclude_stack->exclude_ix];
                dir->exclude_stack = stk->prev;
-               dir->exclude = NULL;
-               free((char *)el->src); /* see strbuf_detach() below */
-               clear_exclude_list(el);
+               dir->pattern = NULL;
+               free((char *)pl->src); /* see strbuf_detach() below */
+               clear_pattern_list(pl);
                free(stk);
                group->nr--;
        }
 
        /* Skip traversing into sub directories if the parent is excluded */
-       if (dir->exclude)
+       if (dir->pattern)
                return;
 
        /*
@@ -1109,7 +1390,7 @@ static void prep_exclude(struct dir_struct *dir,
 
        while (current < baselen) {
                const char *cp;
-               struct sha1_stat sha1_stat;
+               struct oid_stat oid_stat;
 
                stk = xcalloc(1, sizeof(*stk));
                if (current < 0) {
@@ -1129,7 +1410,7 @@ static void prep_exclude(struct dir_struct *dir,
                stk->baselen = cp - base;
                stk->exclude_ix = group->nr;
                stk->ucd = untracked;
-               el = add_exclude_list(dir, EXC_DIRS, NULL);
+               pl = add_pattern_list(dir, EXC_DIRS, NULL);
                strbuf_add(&dir->basebuf, base + current, stk->baselen - current);
                assert(stk->baselen == dir->basebuf.len);
 
@@ -1137,23 +1418,23 @@ static void prep_exclude(struct dir_struct *dir,
                if (stk->baselen) {
                        int dt = DT_DIR;
                        dir->basebuf.buf[stk->baselen - 1] = 0;
-                       dir->exclude = last_exclude_matching_from_lists(dir,
+                       dir->pattern = last_matching_pattern_from_lists(dir,
                                                                        istate,
                                dir->basebuf.buf, stk->baselen - 1,
                                dir->basebuf.buf + current, &dt);
                        dir->basebuf.buf[stk->baselen - 1] = '/';
-                       if (dir->exclude &&
-                           dir->exclude->flags & EXC_FLAG_NEGATIVE)
-                               dir->exclude = NULL;
-                       if (dir->exclude) {
+                       if (dir->pattern &&
+                           dir->pattern->flags & PATTERN_FLAG_NEGATIVE)
+                               dir->pattern = NULL;
+                       if (dir->pattern) {
                                dir->exclude_stack = stk;
                                return;
                        }
                }
 
                /* Try to read per-directory file */
-               hashclr(sha1_stat.sha1);
-               sha1_stat.valid = 0;
+               oidclr(&oid_stat.oid);
+               oid_stat.valid = 0;
                if (dir->exclude_per_dir &&
                    /*
                     * If we know that no files have been added in
@@ -1163,44 +1444,44 @@ static void prep_exclude(struct dir_struct *dir,
                    (!untracked || !untracked->valid ||
                     /*
                      * .. and .gitignore does not exist before
-                     * (i.e. null exclude_sha1). Then we can skip
+                     * (i.e. null exclude_oid). Then we can skip
                      * loading .gitignore, which would result in
                      * ENOENT anyway.
                      */
-                    !is_null_sha1(untracked->exclude_sha1))) {
+                    !is_null_oid(&untracked->exclude_oid))) {
                        /*
                         * dir->basebuf gets reused by the traversal, but we
                         * need fname to remain unchanged to ensure the src
-                        * member of each struct exclude correctly
+                        * member of each struct path_pattern correctly
                         * back-references its source file.  Other invocations
-                        * of add_exclude_list provide stable strings, so we
+                        * of add_pattern_list provide stable strings, so we
                         * strbuf_detach() and free() here in the caller.
                         */
                        struct strbuf sb = STRBUF_INIT;
                        strbuf_addbuf(&sb, &dir->basebuf);
                        strbuf_addstr(&sb, dir->exclude_per_dir);
-                       el->src = strbuf_detach(&sb, NULL);
-                       add_excludes(el->src, el->src, stk->baselen, el, istate,
-                                    untracked ? &sha1_stat : NULL);
+                       pl->src = strbuf_detach(&sb, NULL);
+                       add_patterns(pl->src, pl->src, stk->baselen, pl, istate,
+                                    untracked ? &oid_stat : NULL);
                }
                /*
                 * NEEDSWORK: when untracked cache is enabled, prep_exclude()
                 * will first be called in valid_cached_dir() then maybe many
-                * times more in last_exclude_matching(). When the cache is
-                * used, last_exclude_matching() will not be called and
+                * times more in last_matching_pattern(). When the cache is
+                * used, last_matching_pattern() will not be called and
                 * reading .gitignore content will be a waste.
                 *
                 * So when it's called by valid_cached_dir() and we can get
                 * .gitignore SHA-1 from the index (i.e. .gitignore is not
                 * modified on work tree), we could delay reading the
                 * .gitignore content until we absolutely need it in
-                * last_exclude_matching(). Be careful about ignore rule
+                * last_matching_pattern(). Be careful about ignore rule
                 * order, though, if you do that.
                 */
                if (untracked &&
-                   hashcmp(sha1_stat.sha1, untracked->exclude_sha1)) {
+                   !oideq(&oid_stat.oid, &untracked->exclude_oid)) {
                        invalidate_gitignore(dir->untracked, untracked);
-                       hashcpy(untracked->exclude_sha1, sha1_stat.sha1);
+                       oidcpy(&untracked->exclude_oid, &oid_stat.oid);
                }
                dir->exclude_stack = stk;
                current = stk->baselen;
@@ -1214,7 +1495,7 @@ static void prep_exclude(struct dir_struct *dir,
  * Returns the exclude_list element which matched, or NULL for
  * undecided.
  */
-struct exclude *last_exclude_matching(struct dir_struct *dir,
+struct path_pattern *last_matching_pattern(struct dir_struct *dir,
                                      struct index_state *istate,
                                      const char *pathname,
                                      int *dtype_p)
@@ -1225,10 +1506,10 @@ struct exclude *last_exclude_matching(struct dir_struct *dir,
 
        prep_exclude(dir, istate, pathname, basename-pathname);
 
-       if (dir->exclude)
-               return dir->exclude;
+       if (dir->pattern)
+               return dir->pattern;
 
-       return last_exclude_matching_from_lists(dir, istate, pathname, pathlen,
+       return last_matching_pattern_from_lists(dir, istate, pathname, pathlen,
                        basename, dtype_p);
 }
 
@@ -1240,10 +1521,10 @@ struct exclude *last_exclude_matching(struct dir_struct *dir,
 int is_excluded(struct dir_struct *dir, struct index_state *istate,
                const char *pathname, int *dtype_p)
 {
-       struct exclude *exclude =
-               last_exclude_matching(dir, istate, pathname, dtype_p);
-       if (exclude)
-               return exclude->flags & EXC_FLAG_NEGATIVE ? 0 : 1;
+       struct path_pattern *pattern =
+               last_matching_pattern(dir, istate, pathname, dtype_p);
+       if (pattern)
+               return pattern->flags & PATTERN_FLAG_NEGATIVE ? 0 : 1;
        return 0;
 }
 
@@ -1378,6 +1659,8 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
        const char *dirname, int len, int baselen, int exclude,
        const struct pathspec *pathspec)
 {
+       int nested_repo = 0;
+
        /* The "len-1" is to strip the final '/' */
        switch (directory_exists_in_index(istate, dirname, len-1)) {
        case index_directory:
@@ -1387,12 +1670,42 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
                return path_none;
 
        case index_nonexistent:
+               if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
+                   !(dir->flags & DIR_NO_GITLINKS)) {
+                       struct strbuf sb = STRBUF_INIT;
+                       strbuf_addstr(&sb, dirname);
+                       nested_repo = is_nonbare_repository_dir(&sb);
+                       strbuf_release(&sb);
+               }
+               if (nested_repo)
+                       return ((dir->flags & DIR_SKIP_NESTED_GIT) ? path_none :
+                               (exclude ? path_excluded : path_untracked));
+
                if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
                        break;
-               if (!(dir->flags & DIR_NO_GITLINKS)) {
-                       unsigned char sha1[20];
-                       if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
-                               return exclude ? path_excluded : path_untracked;
+               if (exclude &&
+                       (dir->flags & DIR_SHOW_IGNORED_TOO) &&
+                       (dir->flags & DIR_SHOW_IGNORED_TOO_MODE_MATCHING)) {
+
+                       /*
+                        * This is an excluded directory and we are
+                        * showing ignored paths that match an exclude
+                        * pattern.  (e.g. show directory as ignored
+                        * only if it matches an exclude pattern).
+                        * This path will either be 'path_excluded`
+                        * (if we are showing empty directories or if
+                        * the directory is not empty), or will be
+                        * 'path_none' (empty directory, and we are
+                        * not showing empty directories).
+                        */
+                       if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
+                               return path_excluded;
+
+                       if (read_directory_recursive(dir, istate, dirname, len,
+                                                    untracked, 1, 1, pathspec) == path_excluded)
+                               return path_excluded;
+
+                       return path_none;
                }
                return path_recurse;
        }
@@ -1561,6 +1874,7 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
 {
        int exclude;
        int has_path_in_index = !!index_file_exists(istate, path->buf, path->len, ignore_case);
+       enum path_treatment path_treatment;
 
        if (dtype == DT_UNKNOWN)
                dtype = get_dtype(de, istate, path->buf, path->len);
@@ -1607,8 +1921,23 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
                return path_none;
        case DT_DIR:
                strbuf_addch(path, '/');
-               return treat_directory(dir, istate, untracked, path->buf, path->len,
-                                      baselen, exclude, pathspec);
+               path_treatment = treat_directory(dir, istate, untracked,
+                                                path->buf, path->len,
+                                                baselen, exclude, pathspec);
+               /*
+                * If 1) we only want to return directories that
+                * match an exclude pattern and 2) this directory does
+                * not match an exclude pattern but all of its
+                * contents are excluded, then indicate that we should
+                * recurse into this directory (instead of marking the
+                * directory itself as an ignored path).
+                */
+               if (!exclude &&
+                   path_treatment == path_excluded &&
+                   (dir->flags & DIR_SHOW_IGNORED_TOO) &&
+                   (dir->flags & DIR_SHOW_IGNORED_TOO_MODE_MATCHING))
+                       return path_recurse;
+               return path_treatment;
        case DT_REG:
        case DT_LNK:
                return exclude ? path_excluded : path_untracked;
@@ -1662,7 +1991,7 @@ static enum path_treatment treat_path(struct dir_struct *dir,
        if (!de)
                return treat_path_fast(dir, untracked, cdir, istate, path,
                                       baselen, pathspec);
-       if (is_dot_or_dotdot(de->d_name) || !strcmp(de->d_name, ".git"))
+       if (is_dot_or_dotdot(de->d_name) || !fspathcmp(de->d_name, ".git"))
                return path_none;
        strbuf_setlen(path, baselen);
        strbuf_addstr(path, de->d_name);
@@ -1693,27 +2022,28 @@ static int valid_cached_dir(struct dir_struct *dir,
        if (!untracked)
                return 0;
 
-       if (stat(path->len ? path->buf : ".", &st)) {
-               invalidate_directory(dir->untracked, untracked);
-               memset(&untracked->stat_data, 0, sizeof(untracked->stat_data));
-               return 0;
-       }
-       if (!untracked->valid ||
-           match_stat_data_racy(istate, &untracked->stat_data, &st)) {
-               if (untracked->valid)
-                       invalidate_directory(dir->untracked, untracked);
-               fill_stat_data(&untracked->stat_data, &st);
-               return 0;
+       /*
+        * With fsmonitor, we can trust the untracked cache's valid field.
+        */
+       refresh_fsmonitor(istate);
+       if (!(dir->untracked->use_fsmonitor && untracked->valid)) {
+               if (lstat(path->len ? path->buf : ".", &st)) {
+                       memset(&untracked->stat_data, 0, sizeof(untracked->stat_data));
+                       return 0;
+               }
+               if (!untracked->valid ||
+                       match_stat_data_racy(istate, &untracked->stat_data, &st)) {
+                       fill_stat_data(&untracked->stat_data, &st);
+                       return 0;
+               }
        }
 
-       if (untracked->check_only != !!check_only) {
-               invalidate_directory(dir->untracked, untracked);
+       if (untracked->check_only != !!check_only)
                return 0;
-       }
 
        /*
         * prep_exclude will be called eventually on this directory,
-        * but it's called much later in last_exclude_matching(). We
+        * but it's called much later in last_matching_pattern(). We
         * need it now to determine the validity of the cache for this
         * path. The next calls will be nearly no-op, the way
         * prep_exclude() is designed.
@@ -1736,13 +2066,20 @@ static int open_cached_dir(struct cached_dir *cdir,
                           struct strbuf *path,
                           int check_only)
 {
+       const char *c_path;
+
        memset(cdir, 0, sizeof(*cdir));
        cdir->untracked = untracked;
        if (valid_cached_dir(dir, untracked, istate, path, check_only))
                return 0;
-       cdir->fdir = opendir(path->len ? path->buf : ".");
-       if (dir->untracked)
+       c_path = path->len ? path->buf : ".";
+       cdir->fdir = opendir(c_path);
+       if (!cdir->fdir)
+               warning_errno(_("could not open directory '%s'"), c_path);
+       if (dir->untracked) {
+               invalidate_directory(dir->untracked, untracked);
                dir->untracked->dir_opened++;
+       }
        if (!cdir->fdir)
                return -1;
        return 0;
@@ -1789,6 +2126,40 @@ static void close_cached_dir(struct cached_dir *cdir)
        }
 }
 
+static void add_path_to_appropriate_result_list(struct dir_struct *dir,
+       struct untracked_cache_dir *untracked,
+       struct cached_dir *cdir,
+       struct index_state *istate,
+       struct strbuf *path,
+       int baselen,
+       const struct pathspec *pathspec,
+       enum path_treatment state)
+{
+       /* add the path to the appropriate result list */
+       switch (state) {
+       case path_excluded:
+               if (dir->flags & DIR_SHOW_IGNORED)
+                       dir_add_name(dir, istate, path->buf, path->len);
+               else if ((dir->flags & DIR_SHOW_IGNORED_TOO) ||
+                       ((dir->flags & DIR_COLLECT_IGNORED) &&
+                       exclude_matches_pathspec(path->buf, path->len,
+                                                pathspec)))
+                       dir_add_ignored(dir, istate, path->buf, path->len);
+               break;
+
+       case path_untracked:
+               if (dir->flags & DIR_SHOW_IGNORED)
+                       break;
+               dir_add_name(dir, istate, path->buf, path->len);
+               if (cdir->fdir)
+                       add_untracked(untracked, path->buf + baselen);
+               break;
+
+       default:
+               break;
+       }
+}
+
 /*
  * Read a directory tree. We currently ignore anything but
  * directories, regular files and symlinks. That's because git
@@ -1813,6 +2184,15 @@ static enum path_treatment read_directory_recursive(struct dir_struct *dir,
        struct untracked_cache_dir *untracked, int check_only,
        int stop_at_first_file, const struct pathspec *pathspec)
 {
+       /*
+        * WARNING WARNING WARNING:
+        *
+        * Any updates to the traversal logic here may need corresponding
+        * updates in treat_leading_path().  See the commit message for the
+        * commit adding this warning as well as the commit preceding it
+        * for details.
+        */
+
        struct cached_dir cdir;
        enum path_treatment state, subdir_state, dir_state = path_none;
        struct strbuf path = STRBUF_INIT;
@@ -1836,8 +2216,11 @@ static enum path_treatment read_directory_recursive(struct dir_struct *dir,
                /* recurse into subdir if instructed by treat_path */
                if ((state == path_recurse) ||
                        ((state == path_untracked) &&
-                        (dir->flags & DIR_SHOW_IGNORED_TOO) &&
-                        (get_dtype(cdir.de, istate, path.buf, path.len) == DT_DIR))) {
+                        (get_dtype(cdir.de, istate, path.buf, path.len) == DT_DIR) &&
+                        ((dir->flags & DIR_SHOW_IGNORED_TOO) ||
+                         (pathspec &&
+                          do_match_pathspec(istate, pathspec, path.buf, path.len,
+                                            baselen, NULL, DO_MATCH_LEADING_PATHSPEC) == MATCHED_RECURSIVELY_LEADING_PATHSPEC)))) {
                        struct untracked_cache_dir *ud;
                        ud = lookup_untracked(dir->untracked, untracked,
                                              path.buf + baselen,
@@ -1848,6 +2231,12 @@ static enum path_treatment read_directory_recursive(struct dir_struct *dir,
                                                         check_only, stop_at_first_file, pathspec);
                        if (subdir_state > dir_state)
                                dir_state = subdir_state;
+
+                       if (pathspec &&
+                           !match_pathspec(istate, pathspec, path.buf, path.len,
+                                           0 /* prefix */, NULL,
+                                           0 /* do NOT special case dirs */))
+                               state = path_none;
                }
 
                if (check_only) {
@@ -1883,29 +2272,9 @@ static enum path_treatment read_directory_recursive(struct dir_struct *dir,
                        continue;
                }
 
-               /* add the path to the appropriate result list */
-               switch (state) {
-               case path_excluded:
-                       if (dir->flags & DIR_SHOW_IGNORED)
-                               dir_add_name(dir, istate, path.buf, path.len);
-                       else if ((dir->flags & DIR_SHOW_IGNORED_TOO) ||
-                               ((dir->flags & DIR_COLLECT_IGNORED) &&
-                               exclude_matches_pathspec(path.buf, path.len,
-                                                        pathspec)))
-                               dir_add_ignored(dir, istate, path.buf, path.len);
-                       break;
-
-               case path_untracked:
-                       if (dir->flags & DIR_SHOW_IGNORED)
-                               break;
-                       dir_add_name(dir, istate, path.buf, path.len);
-                       if (cdir.fdir)
-                               add_untracked(untracked, path.buf + baselen);
-                       break;
-
-               default:
-                       break;
-               }
+               add_path_to_appropriate_result_list(dir, untracked, &cdir,
+                                                   istate, &path, baselen,
+                                                   pathspec, state);
        }
        close_cached_dir(&cdir);
  out:
@@ -1935,41 +2304,104 @@ static int treat_leading_path(struct dir_struct *dir,
                              const char *path, int len,
                              const struct pathspec *pathspec)
 {
+       /*
+        * WARNING WARNING WARNING:
+        *
+        * Any updates to the traversal logic here may need corresponding
+        * updates in treat_leading_path().  See the commit message for the
+        * commit adding this warning as well as the commit preceding it
+        * for details.
+        */
+
        struct strbuf sb = STRBUF_INIT;
-       int baselen, rc = 0;
+       int prevlen, baselen;
        const char *cp;
-       int old_flags = dir->flags;
+       struct cached_dir cdir;
+       struct dirent *de;
+       enum path_treatment state = path_none;
+
+       /*
+        * For each directory component of path, we are going to check whether
+        * that path is relevant given the pathspec.  For example, if path is
+        *    foo/bar/baz/
+        * then we will ask treat_path() whether we should go into foo, then
+        * whether we should go into bar, then whether baz is relevant.
+        * Checking each is important because e.g. if path is
+        *    .git/info/
+        * then we need to check .git to know we shouldn't traverse it.
+        * If the return from treat_path() is:
+        *    * path_none, for any path, we return false.
+        *    * path_recurse, for all path components, we return true
+        *    * <anything else> for some intermediate component, we make sure
+        *        to add that path to the relevant list but return false
+        *        signifying that we shouldn't recurse into it.
+        */
 
        while (len && path[len - 1] == '/')
                len--;
        if (!len)
                return 1;
+
+       /*
+        * We need a manufactured dirent with sufficient space to store a
+        * leading directory component of path in its d_name.  Here, we
+        * assume that the dirent's d_name is either declared as
+        *    char d_name[BIG_ENOUGH]
+        * or that it is declared at the end of the struct as
+        *    char d_name[]
+        * For either case, padding with len+1 bytes at the end will ensure
+        * sufficient storage space.
+        */
+       de = xcalloc(1, st_add3(sizeof(struct dirent), len, 1));
+       memset(&cdir, 0, sizeof(cdir));
+       cdir.de = de;
+#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
+       de->d_type = DT_DIR;
+#endif
        baselen = 0;
-       dir->flags &= ~DIR_SHOW_OTHER_DIRECTORIES;
+       prevlen = 0;
        while (1) {
-               cp = path + baselen + !!baselen;
+               prevlen = baselen + !!baselen;
+               cp = path + prevlen;
                cp = memchr(cp, '/', path + len - cp);
                if (!cp)
                        baselen = len;
                else
                        baselen = cp - path;
-               strbuf_setlen(&sb, 0);
+               strbuf_reset(&sb);
                strbuf_add(&sb, path, baselen);
                if (!is_directory(sb.buf))
                        break;
-               if (simplify_away(sb.buf, sb.len, pathspec))
-                       break;
-               if (treat_one_path(dir, NULL, istate, &sb, baselen, pathspec,
-                                  DT_DIR, NULL) == path_none)
+               strbuf_reset(&sb);
+               strbuf_add(&sb, path, prevlen);
+               memcpy(de->d_name, path+prevlen, baselen-prevlen);
+               de->d_name[baselen-prevlen] = '\0';
+               state = treat_path(dir, NULL, &cdir, istate, &sb, prevlen,
+                                   pathspec);
+               if (state == path_untracked &&
+                   get_dtype(cdir.de, istate, sb.buf, sb.len) == DT_DIR &&
+                   (dir->flags & DIR_SHOW_IGNORED_TOO ||
+                    do_match_pathspec(istate, pathspec, sb.buf, sb.len,
+                                      baselen, NULL, DO_MATCH_LEADING_PATHSPEC) == MATCHED_RECURSIVELY_LEADING_PATHSPEC)) {
+                       add_path_to_appropriate_result_list(dir, NULL, &cdir,
+                                                           istate,
+                                                           &sb, baselen,
+                                                           pathspec, state);
+                       state = path_recurse;
+               }
+
+               if (state != path_recurse)
                        break; /* do not recurse into it */
-               if (len <= baselen) {
-                       rc = 1;
+               if (len <= baselen)
                        break; /* finished checking */
-               }
        }
+       add_path_to_appropriate_result_list(dir, NULL, &cdir, istate,
+                                           &sb, baselen, pathspec,
+                                           state);
+
+       free(de);
        strbuf_release(&sb);
-       dir->flags = old_flags;
-       return rc;
+       return state == path_recurse;
 }
 
 static const char *get_ident_string(void)
@@ -2047,8 +2479,13 @@ static struct untracked_cache_dir *validate_untracked_cache(struct dir_struct *d
                                                      const struct pathspec *pathspec)
 {
        struct untracked_cache_dir *root;
+       static int untracked_cache_disabled = -1;
 
-       if (!dir->untracked || getenv("GIT_DISABLE_UNTRACKED_CACHE"))
+       if (!dir->untracked)
+               return NULL;
+       if (untracked_cache_disabled < 0)
+               untracked_cache_disabled = git_env_bool("GIT_DISABLE_UNTRACKED_CACHE", 0);
+       if (untracked_cache_disabled)
                return NULL;
 
        /*
@@ -2099,7 +2536,7 @@ static struct untracked_cache_dir *validate_untracked_cache(struct dir_struct *d
                return NULL;
 
        if (!ident_in_untracked(dir->untracked)) {
-               warning(_("Untracked cache is disabled on this system or location."));
+               warning(_("untracked cache is disabled on this system or location"));
                return NULL;
        }
 
@@ -2111,13 +2548,13 @@ static struct untracked_cache_dir *validate_untracked_cache(struct dir_struct *d
 
        /* Validate $GIT_DIR/info/exclude and core.excludesfile */
        root = dir->untracked->root;
-       if (hashcmp(dir->ss_info_exclude.sha1,
-                   dir->untracked->ss_info_exclude.sha1)) {
+       if (!oideq(&dir->ss_info_exclude.oid,
+                  &dir->untracked->ss_info_exclude.oid)) {
                invalidate_gitignore(dir->untracked, root);
                dir->untracked->ss_info_exclude = dir->ss_info_exclude;
        }
-       if (hashcmp(dir->ss_excludes_file.sha1,
-                   dir->untracked->ss_excludes_file.sha1)) {
+       if (!oideq(&dir->ss_excludes_file.oid,
+                  &dir->untracked->ss_excludes_file.oid)) {
                invalidate_gitignore(dir->untracked, root);
                dir->untracked->ss_excludes_file = dir->ss_excludes_file;
        }
@@ -2132,8 +2569,12 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,
 {
        struct untracked_cache_dir *untracked;
 
-       if (has_symlink_leading_path(path, len))
+       trace_performance_enter();
+
+       if (has_symlink_leading_path(path, len)) {
+               trace_performance_leave("read directory %.*s", len, path);
                return dir->nr;
+       }
 
        untracked = validate_untracked_cache(dir, len, pathspec);
        if (!untracked)
@@ -2169,8 +2610,14 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,
                dir->nr = i;
        }
 
+       trace_performance_leave("read directory %.*s", len, path);
        if (dir->untracked) {
+               static int force_untracked_cache = -1;
                static struct trace_key trace_untracked_stats = TRACE_KEY_INIT(UNTRACKED_STATS);
+
+               if (force_untracked_cache < 0)
+                       force_untracked_cache =
+                               git_env_bool("GIT_FORCE_UNTRACKED_CACHE", 0);
                trace_printf_key(&trace_untracked_stats,
                                 "node creation: %u\n"
                                 "gitignore invalidation: %u\n"
@@ -2180,7 +2627,8 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,
                                 dir->untracked->gitignore_invalidated,
                                 dir->untracked->dir_invalidated,
                                 dir->untracked->dir_opened);
-               if (dir->untracked == istate->untracked &&
+               if (force_untracked_cache &&
+                       dir->untracked == istate->untracked &&
                    (dir->untracked->dir_opened ||
                     dir->untracked->gitignore_invalidated ||
                     dir->untracked->dir_invalidated))
@@ -2198,6 +2646,14 @@ int file_exists(const char *f)
        return lstat(f, &sb) == 0;
 }
 
+int repo_file_exists(struct repository *repo, const char *path)
+{
+       if (repo != the_repository)
+               BUG("do not know how to check file existence in arbitrary repo");
+
+       return file_exists(path);
+}
+
 static int cmp_icase(char a, char b)
 {
        if (a == b)
@@ -2279,10 +2735,10 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
        int ret = 0, original_len = path->len, len, kept_down = 0;
        int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
        int keep_toplevel = (flag & REMOVE_DIR_KEEP_TOPLEVEL);
-       unsigned char submodule_head[20];
+       struct object_id submodule_head;
 
        if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
-           !resolve_gitlink_ref(path->buf, "HEAD", submodule_head)) {
+           !resolve_gitlink_ref(path->buf, "HEAD", &submodule_head)) {
                /* Do not descend and nuke a nested git work tree. */
                if (kept_up)
                        *kept_up = 1;
@@ -2320,7 +2776,7 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
                                 * wanted anyway
                                 */
                                continue;
-                       /* fall thru */
+                       /* fall through */
                } else if (S_ISDIR(st.st_mode)) {
                        if (!remove_dir_recurse(path, flag, &kept_down))
                                continue; /* happy */
@@ -2358,18 +2814,18 @@ void setup_standard_excludes(struct dir_struct *dir)
 {
        dir->exclude_per_dir = ".gitignore";
 
-       /* core.excludefile defaulting to $XDG_HOME/git/ignore */
+       /* core.excludesfile defaulting to $XDG_CONFIG_HOME/git/ignore */
        if (!excludes_file)
                excludes_file = xdg_config_home("ignore");
        if (excludes_file && !access_or_warn(excludes_file, R_OK, 0))
-               add_excludes_from_file_1(dir, excludes_file,
+               add_patterns_from_file_1(dir, excludes_file,
                                         dir->untracked ? &dir->ss_excludes_file : NULL);
 
        /* per repository user preference */
        if (startup_info->have_repository) {
                const char *path = git_path_info_exclude();
                if (!access_or_warn(path, R_OK, 0))
-                       add_excludes_from_file_1(dir, path,
+                       add_patterns_from_file_1(dir, path,
                                                 dir->untracked ? &dir->ss_info_exclude : NULL);
        }
 }
@@ -2401,18 +2857,18 @@ void clear_directory(struct dir_struct *dir)
 {
        int i, j;
        struct exclude_list_group *group;
-       struct exclude_list *el;
+       struct pattern_list *pl;
        struct exclude_stack *stk;
 
        for (i = EXC_CMDL; i <= EXC_FILE; i++) {
                group = &dir->exclude_list_group[i];
                for (j = 0; j < group->nr; j++) {
-                       el = &group->el[j];
+                       pl = &group->pl[j];
                        if (i == EXC_DIRS)
-                               free((char *)el->src);
-                       clear_exclude_list(el);
+                               free((char *)pl->src);
+                       clear_pattern_list(pl);
                }
-               free(group->el);
+               free(group->pl);
        }
 
        stk = dir->exclude_stack;
@@ -2428,13 +2884,9 @@ struct ondisk_untracked_cache {
        struct stat_data info_exclude_stat;
        struct stat_data excludes_file_stat;
        uint32_t dir_flags;
-       unsigned char info_exclude_sha1[20];
-       unsigned char excludes_file_sha1[20];
-       char exclude_per_dir[FLEX_ARRAY];
 };
 
 #define ouc_offset(x) offsetof(struct ondisk_untracked_cache, x)
-#define ouc_size(len) (ouc_offset(exclude_per_dir) + len + 1)
 
 struct write_data {
        int index;         /* number of written untracked_cache_dir */
@@ -2484,9 +2936,10 @@ static void write_one_dir(struct untracked_cache_dir *untracked,
                stat_data_to_disk(&stat_data, &untracked->stat_data);
                strbuf_add(&wd->sb_stat, &stat_data, sizeof(stat_data));
        }
-       if (!is_null_sha1(untracked->exclude_sha1)) {
+       if (!is_null_oid(&untracked->exclude_oid)) {
                ewah_set(wd->sha1_valid, i);
-               strbuf_add(&wd->sb_sha1, untracked->exclude_sha1, 20);
+               strbuf_add(&wd->sb_sha1, untracked->exclude_oid.hash,
+                          the_hash_algo->rawsz);
        }
 
        intlen = encode_varint(untracked->untracked_nr, intbuf);
@@ -2516,20 +2969,21 @@ void write_untracked_extension(struct strbuf *out, struct untracked_cache *untra
        struct write_data wd;
        unsigned char varbuf[16];
        int varint_len;
-       size_t len = strlen(untracked->exclude_per_dir);
+       const unsigned hashsz = the_hash_algo->rawsz;
 
-       FLEX_ALLOC_MEM(ouc, exclude_per_dir, untracked->exclude_per_dir, len);
+       ouc = xcalloc(1, sizeof(*ouc));
        stat_data_to_disk(&ouc->info_exclude_stat, &untracked->ss_info_exclude.stat);
        stat_data_to_disk(&ouc->excludes_file_stat, &untracked->ss_excludes_file.stat);
-       hashcpy(ouc->info_exclude_sha1, untracked->ss_info_exclude.sha1);
-       hashcpy(ouc->excludes_file_sha1, untracked->ss_excludes_file.sha1);
        ouc->dir_flags = htonl(untracked->dir_flags);
 
        varint_len = encode_varint(untracked->ident.len, varbuf);
        strbuf_add(out, varbuf, varint_len);
        strbuf_addbuf(out, &untracked->ident);
 
-       strbuf_add(out, ouc, ouc_size(len));
+       strbuf_add(out, ouc, sizeof(*ouc));
+       strbuf_add(out, untracked->ss_info_exclude.oid.hash, hashsz);
+       strbuf_add(out, untracked->ss_excludes_file.oid.hash, hashsz);
+       strbuf_add(out, untracked->exclude_per_dir, strlen(untracked->exclude_per_dir) + 1);
        FREE_AND_NULL(ouc);
 
        if (!untracked->root) {
@@ -2614,54 +3068,49 @@ static int read_one_dir(struct untracked_cache_dir **untracked_,
                        struct read_data *rd)
 {
        struct untracked_cache_dir ud, *untracked;
-       const unsigned char *next, *data = rd->data, *end = rd->end;
+       const unsigned char *data = rd->data, *end = rd->end;
+       const unsigned char *eos;
        unsigned int value;
-       int i, len;
+       int i;
 
        memset(&ud, 0, sizeof(ud));
 
-       next = data;
-       value = decode_varint(&next);
-       if (next > end)
+       value = decode_varint(&data);
+       if (data > end)
                return -1;
        ud.recurse         = 1;
        ud.untracked_alloc = value;
        ud.untracked_nr    = value;
        if (ud.untracked_nr)
                ALLOC_ARRAY(ud.untracked, ud.untracked_nr);
-       data = next;
 
-       next = data;
-       ud.dirs_alloc = ud.dirs_nr = decode_varint(&next);
-       if (next > end)
+       ud.dirs_alloc = ud.dirs_nr = decode_varint(&data);
+       if (data > end)
                return -1;
        ALLOC_ARRAY(ud.dirs, ud.dirs_nr);
-       data = next;
 
-       len = strlen((const char *)data);
-       next = data + len + 1;
-       if (next > rd->end)
+       eos = memchr(data, '\0', end - data);
+       if (!eos || eos == end)
                return -1;
-       *untracked_ = untracked = xmalloc(st_add(sizeof(*untracked), len));
+
+       *untracked_ = untracked = xmalloc(st_add3(sizeof(*untracked), eos - data, 1));
        memcpy(untracked, &ud, sizeof(ud));
-       memcpy(untracked->name, data, len + 1);
-       data = next;
+       memcpy(untracked->name, data, eos - data + 1);
+       data = eos + 1;
 
        for (i = 0; i < untracked->untracked_nr; i++) {
-               len = strlen((const char *)data);
-               next = data + len + 1;
-               if (next > rd->end)
+               eos = memchr(data, '\0', end - data);
+               if (!eos || eos == end)
                        return -1;
-               untracked->untracked[i] = xstrdup((const char*)data);
-               data = next;
+               untracked->untracked[i] = xmemdupz(data, eos - data);
+               data = eos + 1;
        }
 
        rd->ucd[rd->index++] = untracked;
        rd->data = data;
 
        for (i = 0; i < untracked->dirs_nr; i++) {
-               len = read_one_dir(untracked->dirs + i, rd);
-               if (len < 0)
+               if (read_one_dir(untracked->dirs + i, rd) < 0)
                        return -1;
        }
        return 0;
@@ -2687,25 +3136,24 @@ static void read_stat(size_t pos, void *cb)
        ud->valid = 1;
 }
 
-static void read_sha1(size_t pos, void *cb)
+static void read_oid(size_t pos, void *cb)
 {
        struct read_data *rd = cb;
        struct untracked_cache_dir *ud = rd->ucd[pos];
-       if (rd->data + 20 > rd->end) {
+       if (rd->data + the_hash_algo->rawsz > rd->end) {
                rd->data = rd->end + 1;
                return;
        }
-       hashcpy(ud->exclude_sha1, rd->data);
-       rd->data += 20;
+       hashcpy(ud->exclude_oid.hash, rd->data);
+       rd->data += the_hash_algo->rawsz;
 }
 
-static void load_sha1_stat(struct sha1_stat *sha1_stat,
-                          const unsigned char *data,
-                          const unsigned char *sha1)
+static void load_oid_stat(struct oid_stat *oid_stat, const unsigned char *data,
+                         const unsigned char *sha1)
 {
-       stat_data_from_disk(&sha1_stat->stat, data);
-       hashcpy(sha1_stat->sha1, sha1);
-       sha1_stat->valid = 1;
+       stat_data_from_disk(&oid_stat->stat, data);
+       hashcpy(oid_stat->oid.hash, sha1);
+       oid_stat->valid = 1;
 }
 
 struct untracked_cache *read_untracked_extension(const void *data, unsigned long sz)
@@ -2714,8 +3162,12 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
        struct read_data rd;
        const unsigned char *next = data, *end = (const unsigned char *)data + sz;
        const char *ident;
-       int ident_len, len;
+       int ident_len;
+       ssize_t len;
        const char *exclude_per_dir;
+       const unsigned hashsz = the_hash_algo->rawsz;
+       const unsigned offset = sizeof(struct ondisk_untracked_cache);
+       const unsigned exclude_per_dir_offset = offset + 2 * hashsz;
 
        if (sz <= 1 || end[-1] != '\0')
                return NULL;
@@ -2727,23 +3179,23 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
        ident = (const char *)next;
        next += ident_len;
 
-       if (next + ouc_size(0) > end)
+       if (next + exclude_per_dir_offset + 1 > end)
                return NULL;
 
        uc = xcalloc(1, sizeof(*uc));
        strbuf_init(&uc->ident, ident_len);
        strbuf_add(&uc->ident, ident, ident_len);
-       load_sha1_stat(&uc->ss_info_exclude,
-                      next + ouc_offset(info_exclude_stat),
-                      next + ouc_offset(info_exclude_sha1));
-       load_sha1_stat(&uc->ss_excludes_file,
-                      next + ouc_offset(excludes_file_stat),
-                      next + ouc_offset(excludes_file_sha1));
+       load_oid_stat(&uc->ss_info_exclude,
+                     next + ouc_offset(info_exclude_stat),
+                     next + offset);
+       load_oid_stat(&uc->ss_excludes_file,
+                     next + ouc_offset(excludes_file_stat),
+                     next + offset + hashsz);
        uc->dir_flags = get_be32(next + ouc_offset(dir_flags));
-       exclude_per_dir = (const char *)next + ouc_offset(exclude_per_dir);
+       exclude_per_dir = (const char *)next + exclude_per_dir_offset;
        uc->exclude_per_dir = xstrdup(exclude_per_dir);
        /* NUL after exclude_per_dir is covered by sizeof(*ouc) */
-       next += ouc_size(strlen(exclude_per_dir));
+       next += exclude_per_dir_offset + strlen(exclude_per_dir) + 1;
        if (next >= end)
                goto done2;
 
@@ -2780,7 +3232,7 @@ struct untracked_cache *read_untracked_extension(const void *data, unsigned long
        ewah_each_bit(rd.check_only, set_check_only, &rd);
        rd.data = next + len;
        ewah_each_bit(rd.valid, read_stat, &rd);
-       ewah_each_bit(rd.sha1_valid, read_sha1, &rd);
+       ewah_each_bit(rd.sha1_valid, read_oid, &rd);
        next = rd.data;
 
 done:
@@ -2851,10 +3303,12 @@ static int invalidate_one_component(struct untracked_cache *uc,
 }
 
 void untracked_cache_invalidate_path(struct index_state *istate,
-                                    const char *path)
+                                    const char *path, int safe_path)
 {
        if (!istate->untracked || !istate->untracked->root)
                return;
+       if (!safe_path && !verify_path(path, 0))
+               return;
        invalidate_one_component(istate->untracked, istate->untracked->root,
                                 path, strlen(path));
 }
@@ -2862,17 +3316,66 @@ void untracked_cache_invalidate_path(struct index_state *istate,
 void untracked_cache_remove_from_index(struct index_state *istate,
                                       const char *path)
 {
-       untracked_cache_invalidate_path(istate, path);
+       untracked_cache_invalidate_path(istate, path, 1);
 }
 
 void untracked_cache_add_to_index(struct index_state *istate,
                                  const char *path)
 {
-       untracked_cache_invalidate_path(istate, path);
+       untracked_cache_invalidate_path(istate, path, 1);
 }
 
-/* Update gitfile and core.worktree setting to connect work tree and git dir */
-void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_)
+static void connect_wt_gitdir_in_nested(const char *sub_worktree,
+                                       const char *sub_gitdir)
+{
+       int i;
+       struct repository subrepo;
+       struct strbuf sub_wt = STRBUF_INIT;
+       struct strbuf sub_gd = STRBUF_INIT;
+
+       const struct submodule *sub;
+
+       /* If the submodule has no working tree, we can ignore it. */
+       if (repo_init(&subrepo, sub_gitdir, sub_worktree))
+               return;
+
+       if (repo_read_index(&subrepo) < 0)
+               die(_("index file corrupt in repo %s"), subrepo.gitdir);
+
+       for (i = 0; i < subrepo.index->cache_nr; i++) {
+               const struct cache_entry *ce = subrepo.index->cache[i];
+
+               if (!S_ISGITLINK(ce->ce_mode))
+                       continue;
+
+               while (i + 1 < subrepo.index->cache_nr &&
+                      !strcmp(ce->name, subrepo.index->cache[i + 1]->name))
+                       /*
+                        * Skip entries with the same name in different stages
+                        * to make sure an entry is returned only once.
+                        */
+                       i++;
+
+               sub = submodule_from_path(&subrepo, &null_oid, ce->name);
+               if (!sub || !is_submodule_active(&subrepo, ce->name))
+                       /* .gitmodules broken or inactive sub */
+                       continue;
+
+               strbuf_reset(&sub_wt);
+               strbuf_reset(&sub_gd);
+               strbuf_addf(&sub_wt, "%s/%s", sub_worktree, sub->path);
+               strbuf_addf(&sub_gd, "%s/modules/%s", sub_gitdir, sub->name);
+
+               connect_work_tree_and_git_dir(sub_wt.buf, sub_gd.buf, 1);
+       }
+       strbuf_release(&sub_wt);
+       strbuf_release(&sub_gd);
+       repo_clear(&subrepo);
+}
+
+void connect_work_tree_and_git_dir(const char *work_tree_,
+                                  const char *git_dir_,
+                                  int recurse_into_nested)
 {
        struct strbuf gitfile_sb = STRBUF_INIT;
        struct strbuf cfg_sb = STRBUF_INIT;
@@ -2902,6 +3405,10 @@ void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_)
        strbuf_release(&gitfile_sb);
        strbuf_release(&cfg_sb);
        strbuf_release(&rel_path);
+
+       if (recurse_into_nested)
+               connect_wt_gitdir_in_nested(work_tree, git_dir);
+
        free(work_tree);
        free(git_dir);
 }
@@ -2915,5 +3422,5 @@ void relocate_gitdir(const char *path, const char *old_git_dir, const char *new_
                die_errno(_("could not migrate git directory from '%s' to '%s'"),
                        old_git_dir, new_git_dir);
 
-       connect_work_tree_and_git_dir(path, new_git_dir);
+       connect_work_tree_and_git_dir(path, new_git_dir, 0);
 }