1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /*
18  * State information for a tracked file in a work tree.
19  * When written to disk, multi-byte fields are written in big-endian.
20  * Some fields are based on results from stat(2). These are only used in
21  * order to detect modifications made to on-disk files, they are never
22  * applied back to the filesystem.
23  */
24 struct got_file_index_entry {
25 	TAILQ_ENTRY(, got_file_index_entry) entry;
26 	uint64_t ctime_sec;
27 	uint64_t ctime_nsec;
28 	uint64_t mtime_sec;
29 	uint64_t mtime_nsec;
30 	uint32_t uid;
31 	uint32_t gid;
32 	/*
33 	 * On-disk size is truncated to the lower 32 bits.
34 	 * The value is only used to check for modifications anyway.
35 	 */
36 	uint32_t size;
37 	uint16_t mode;
38 #define GOT_INDEX_ENTRY_MODE_OBJ_TYPE	0x000f
39 #define GOT_INDEX_ENTRY_MODE_PERMS	0xff10
40 
41 	/* SHA1 of corresponding blob in repository. */
42 	uint8_t blob_sha1[SHA1_DIGEST_LENGTH];
43 
44 	uint32_t flags;
45 #define GOT_INDEX_ENTRY_F_PATH_LEN	0x00000fff
46 #define GOT_INDEX_ENTRY_F_STAGE		0x00003000
47 #define GOT_INDEX_ENTRY_F_EXTENDED	0x00004000
48 #define GOT_INDEX_ENTRY_F_ASSUME_VALID	0x00008000
49 
50 	/*
51 	 * UNIX-style path, relative to work tree root.
52 	 * Variable length, and NUL-padded to a multiple of 8 on disk.
53 	 */
54 	const char *path;
55 };
56 
57 /* "Stages" of a file afflicted by a 3-way merge conflict. */
58 #define GOT_INDEX_ENTRY_STAGE_MERGED	0
59 #define GOT_INDEX_ENTRY_STAGE_ANCESTOR	1
60 #define GOT_INDEX_ENTRY_STAGE_OURS	2
61 #define GOT_INDEX_ENTRY_STAGE_THEIRS	3
62 
63 /* On-disk file index header structure. */
64 struct got_file_index_hdr {
65 	uint32_t signature;	/* big-endian on disk */
66 	uint32_t version;	/* big-endian on disk */
67 	uint32_t nentries;	/* big-endian on disk */
68 	TAILQ_HEAD(, got_file_index_entry) entries;
69 	uint8_t sha1[SHA1_DIGEST_LENGTH]; /* checksum of above on-disk data */
70 };