1This file tries to document file related requests a client can make
2to the ADB server of an adbd daemon. See the OVERVIEW.TXT document
3to understand what's going on here. See the SERVICES.TXT to learn more
4about the other requests that are possible.
5
6SYNC SERVICES:
7
8
9Requesting the sync service ("sync:") using the protocol as described in
10SERVICES.TXT sets the connection in sync mode. This mode is a binary mode that
11differ from the regular adb protocol. The connection stays in sync mode until
12explicitly terminated (see below).
13
14After the initial "sync:" command is sent the server must respond with either
15"OKAY" or "FAIL" as per usual. 
16
17In sync mode both the server and the client will frequently use eight-byte
18packets to communicate in this document called sync request and sync
19responses. The first four bytes is an id and specifies sync request is
20represented by four utf-8 characters. The last four bytes is a Little-Endian
21integer, with various uses. This number will be called "length" below. In fact
22all binary integers are Little-Endian in the sync mode. Sync mode is
23implicitly exited after each sync request, and normal adb communication
24follows as described in SERVICES.TXT.
25
26The following sync requests are accepted:
27LIST - List the files in a folder
28SEND - Send a file to device
29RECV - Retreive a file from device
30
31Not yet documented:
32STAT - Stat a file
33ULNK - Unlink (remove) a file. (Not currently supported)
34
35For all of the sync request above the must be followed by length number of
36bytes containing an utf-8 string with a remote filename.
37
38LIST:
39Lists files in the directory specified by the remote filename. The server will
40respond with zero or more directory entries or "dents".
41
42The directory entries will be returned in the following form
431. A four-byte sync response id beeing "DENT"
442. A four-byte integer representing file mode.
453. A four-byte integer representing file size.
464. A four-byte integer representing last modified time.
475. A four-byte integer representing file name length.
486. length number of bytes containing an utf-8 string representing the file
49   name.
50
51When an sync response "DONE" is received the listing is done.
52
53SEND:
54The remote file name is split into two parts separated by the last
55comma (","). The first part is the actual path, while the second is a decimal
56encoded file mode containing the permissions of the file on device.
57
58Note that some file types will be deleted before the copying starts, and if
59the transfer fails. Some file types will not be deleted, which allows
60  adb push disk_image /some_block_device
61to work.
62
63After this the actual file is sent in chunks. Each chucks has the following
64format.
65A sync request with id "DATA" and length equal to the chunk size. After
66follows chunk size number of bytes. This is repeated until the file is
67transfered. Each chunk must not be larger than 64k.
68
69When the file is tranfered a sync request "DONE" is sent, where length is set
70to the last modified time for the file. The server responds to this last
71request (but not to chuck requests) with an "OKAY" sync response (length can
72be ignored).
73
74
75RECV:
76Retrieves a file from device to a local file. The remote path is the path to
77the file that will be returned. Just as for the SEND sync request the file
78received is split up into chunks. The sync response id is "DATA" and length is
79the chuck size. After follows chunk size number of bytes. This is repeated
80until the file is transfered. Each chuck will not be larger than 64k.
81
82When the file is transfered a sync resopnse "DONE" is retrieved where the
83length can be ignored.
84
85