[PATCH v2 10/22] untracked cache: load from UNTR index extension

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 dir.c        | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 dir.h        |   2 +
 read-cache.c |   5 +++
 3 files changed, 142 insertions(+)

diff --git a/dir.c b/dir.c
index 4e15f20..bc196b3 100644
--- a/dir.c
+++ b/dir.c
@@ -2223,3 +2223,138 @@ void write_untracked_extension(struct strbuf *out, struct untracked_cache *untra
 	if (untracked->root)
 		write_one_dir(out, untracked->root);
 }
+
+static void free_untracked(struct untracked_cache_dir *ucd)
+{
+	int i;
+	if (!ucd)
+		return;
+	for (i = 0; i < ucd->dirs_nr; i++)
+		free_untracked(ucd->dirs[i]);
+	for (i = 0; i < ucd->untracked_nr; i++)
+		free(ucd->untracked[i]);
+	free(ucd->untracked);
+	free(ucd->dirs);
+	free(ucd);
+}
+
+void free_untracked_cache(struct untracked_cache *uc)
+{
+	if (uc)
+		free_untracked(uc->root);
+	free(uc);
+}
+
+static void stat_data_from_disk(struct stat_data *to, const struct stat_data *from)
+{
+	to->sd_ctime.sec  = get_be32(&from->sd_ctime.sec);
+	to->sd_ctime.nsec = get_be32(&from->sd_ctime.nsec);
+	to->sd_mtime.sec  = get_be32(&from->sd_mtime.sec);
+	to->sd_mtime.nsec = get_be32(&from->sd_mtime.nsec);
+	to->sd_dev	  = get_be32(&from->sd_dev);
+	to->sd_ino	  = get_be32(&from->sd_ino);
+	to->sd_uid	  = get_be32(&from->sd_uid);
+	to->sd_gid	  = get_be32(&from->sd_gid);
+	to->sd_size	  = get_be32(&from->sd_size);
+}
+
+static int read_one_dir(struct untracked_cache_dir **untracked_,
+			const unsigned char *data_, unsigned long sz)
+{
+#define NEXT(x) \
+	next = data + (x); \
+	if (next > data_ + sz) \
+		return -1;
+
+	struct untracked_cache_dir ud, *untracked;
+	const unsigned char *next, *data = data_;
+	unsigned int value;
+	int i, len;
+
+	memset(&ud, 0, sizeof(ud));
+
+	NEXT(sizeof(struct stat_data));
+	stat_data_from_disk(&ud.stat_data, (struct stat_data *)data);
+	data = next;
+
+	NEXT(20);
+	hashcpy(ud.exclude_sha1, data);
+	data = next;
+
+	next = data;
+	value = decode_varint(&next);
+	if (next > data_ + sz)
+		return -1;
+	ud.recurse = 1;
+	ud.valid = value & 1;
+	ud.check_only = (value >> 1) & 1;
+	ud.untracked_alloc = ud.untracked_nr = value >> 2;
+	if (ud.untracked_nr)
+		ud.untracked = xmalloc(sizeof(*ud.untracked) * ud.untracked_nr);
+	data = next;
+
+	next = data;
+	ud.dirs_alloc = ud.dirs_nr = decode_varint(&next);
+	if (next > data_ + sz)
+		return -1;
+	ud.dirs = xmalloc(sizeof(*ud.dirs) * ud.dirs_nr);
+	data = next;
+
+	len = strlen((const char *)data);
+	NEXT(len + 1);
+	*untracked_ = untracked = xmalloc(sizeof(*untracked) + len);
+	memcpy(untracked, &ud, sizeof(ud));
+	memcpy(untracked->name, data, len + 1);
+	data = next;
+
+	for (i = 0; i < untracked->untracked_nr; i++) {
+		len = strlen((const char *)data);
+		NEXT(len + 1);
+		untracked->untracked[i] = xstrdup((const char*)data);
+		data = next;
+	}
+
+	for (i = 0; i < untracked->dirs_nr; i++) {
+		len = read_one_dir(untracked->dirs + i, data, sz - (data - data_));
+		if (len < 0)
+			return -1;
+		data += len;
+	}
+	return data - data_;
+}
+
+static void load_sha1_stat(struct sha1_stat *sha1_stat,
+			   const struct stat_data *stat,
+			   const unsigned char *sha1)
+{
+	stat_data_from_disk(&sha1_stat->stat, stat);
+	hashcpy(sha1_stat->sha1, sha1);
+	sha1_stat->valid = 1;
+}
+
+struct untracked_cache *read_untracked_extension(const void *data, unsigned long sz)
+{
+	const struct ondisk_untracked_cache *ouc = data;
+	struct untracked_cache *uc;
+	int len;
+
+	if (sz < sizeof(*ouc))
+		return NULL;
+
+	uc = xcalloc(1, sizeof(*uc));
+	load_sha1_stat(&uc->ss_info_exclude, &ouc->info_exclude_stat,
+		       ouc->info_exclude_sha1);
+	load_sha1_stat(&uc->ss_excludes_file, &ouc->excludes_file_stat,
+		       ouc->excludes_file_sha1);
+	uc->dir_flags = get_be32(&ouc->dir_flags);
+	uc->exclude_per_dir = xstrdup(ouc->exclude_per_dir);
+	len = sizeof(*ouc) + strlen(ouc->exclude_per_dir);
+	if (sz == len)
+		return uc;
+	if (sz > len &&
+	    read_one_dir(&uc->root, (const unsigned char *)data + len,
+			 sz - len) == sz - len)
+		return uc;
+	free_untracked_cache(uc);
+	return NULL;
+}
diff --git a/dir.h b/dir.h
index c771057..14ee4fd 100644
--- a/dir.h
+++ b/dir.h
@@ -298,5 +298,7 @@ static inline int dir_path_match(const struct dir_entry *ent,
 			      has_trailing_dir);
 }
 
+void free_untracked_cache(struct untracked_cache *);
+struct untracked_cache *read_untracked_extension(const void *data, unsigned long sz);
 void write_untracked_extension(struct strbuf *out, struct untracked_cache *untracked);
 #endif
diff --git a/read-cache.c b/read-cache.c
index 26e938d..f5bd174 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1366,6 +1366,9 @@ static int read_index_extension(struct index_state *istate,
 		if (read_link_extension(istate, data, sz))
 			return -1;
 		break;
+	case CACHE_EXT_UNTRACKED:
+		istate->untracked = read_untracked_extension(data, sz);
+		break;
 	default:
 		if (*ext < 'A' || 'Z' < *ext)
 			return error("index uses %.4s extension, which we do not understand",
@@ -1631,6 +1634,8 @@ int discard_index(struct index_state *istate)
 	istate->cache = NULL;
 	istate->cache_alloc = 0;
 	discard_split_index(istate);
+	free_untracked_cache(istate->untracked);
+	istate->untracked = NULL;
 	return 0;
 }
 
-- 
2.1.0.rc0.78.gc0d8480