blob: 0014fd416174e5adbf1badb2f4b195d38ddce099 [file] [log] [blame]
Patrick Ventureef3aead2018-09-12 08:53:29 -07001#pragma once
2
3#include <string>
4#include <vector>
5
6namespace blobs
7{
8
9enum OpenFlags
10{
11 read = (1 << 0),
12 write = (1 << 1),
13 /* bits 3-7 reserved. */
14 /* bits 8-15 given blob-specific definitions */
15};
16
17enum StateFlags
18{
19 open_read = (1 << 0),
20 open_write = (1 << 1),
21 committing = (1 << 2),
22 committed = (1 << 3),
23 commit_error = (1 << 4),
24};
25
26struct BlobMeta
27{
28 uint16_t blobState;
29 uint32_t size;
30 std::vector<uint8_t> metadata;
31};
32
33/*
34 * All blob specific objects implement this interface.
35 */
36class GenericBlobInterface
37{
38 public:
39 virtual ~GenericBlobInterface() = default;
40
41 /**
42 * Checks if the handler will manage this file path.
43 *
44 * @param[in] blobId.
45 * @return bool whether it will manage the file path.
46 */
47 virtual bool canHandleBlob(const std::string& path) = 0;
48
49 /**
50 * Return the name(s) of the blob(s). Used during GetCount.
51 *
52 * @return List of blobIds this handler manages.
53 */
54 virtual std::vector<std::string> getBlobIds() = 0;
55
56 /**
57 * Attempt to delete the blob specified by the path.
58 *
59 * @param[in] path - the blobId to try and delete.
60 * @return bool - whether it was able to delete the blob.
61 */
62 virtual bool deleteBlob(const std::string& path) = 0;
63
64 /**
65 * Return metadata about the blob.
66 *
67 * @param[in] path - the blobId for metadata.
68 * @param[in,out] meta - a pointer to a blobmeta.
69 * @return bool - true if it was successful.
70 */
71 virtual bool stat(const std::string& path, struct BlobMeta* meta) = 0;
72
73 /* The methods below are per session. */
74
75 /**
76 * Attempt to open a session from this path.
77 *
78 * @param[in] session - the session id.
79 * @param[in] flags - the open flags.
80 * @param[in] path - the blob path.
81 * @return bool - was able to open the session.
82 */
83 virtual bool open(uint16_t session, uint16_t flags,
84 const std::string& path) = 0;
85
86 /**
87 * Attempt to read from a blob.
88 *
89 * @param[in] session - the session id.
90 * @param[in] offset - offset into the blob.
91 * @param[in] requestedSize - number of bytes to read.
92 * @return Bytes read back (0 length on error).
93 */
94 virtual std::vector<uint8_t> read(uint16_t session, uint32_t offset,
95 uint32_t requestedSize) = 0;
96
97 /**
98 * Attempt to write to a blob.
99 *
100 * @param[in] session - the session id.
101 * @param[in] offset - offset into the blob.
102 * @param[in] data - the data to write.
103 * @return bool - was able to write.
104 */
105 virtual bool write(uint16_t session, uint32_t offset,
106 const std::vector<uint8_t>& data) = 0;
107
108 /**
Patrick Venture5c4b17b2018-10-04 10:32:22 -0700109 * Attempt to write metadata to a blob.
110 *
111 * @param[in] session - the session id.
112 * @param[in] offset - offset into the blob.
113 * @param[in] data - the data to write.
114 * @return bool - was able to write.
115 */
116 virtual bool writeMeta(uint16_t session, uint32_t offset,
117 const std::vector<uint8_t>& data) = 0;
118
119 /**
Patrick Ventureef3aead2018-09-12 08:53:29 -0700120 * Attempt to commit to a blob.
121 *
122 * @param[in] session - the session id.
123 * @param[in] data - optional commit data.
124 * @return bool - was able to start commit.
125 */
126 virtual bool commit(uint16_t session, const std::vector<uint8_t>& data) = 0;
127
128 /**
129 * Attempt to close your session.
130 *
131 * @param[in] session - the session id.
132 * @return bool - was able to close session.
133 */
134 virtual bool close(uint16_t session) = 0;
135
136 /**
137 * Attempt to return metadata for the session's view of the blob.
138 *
139 * @param[in] session - the session id.
140 * @param[in,out] meta - pointer to update with the BlobMeta.
141 * @return bool - wether it was successful.
142 */
143 virtual bool stat(uint16_t session, struct BlobMeta* meta) = 0;
144
145 /**
146 * Attempt to expire a session. This is called when a session has been
147 * inactive for at least 10 minutes.
148 *
149 * @param[in] session - the session id.
150 * @return bool - whether the session was able to be closed.
151 */
152 virtual bool expire(uint16_t session) = 0;
153};
154} // namespace blobs