README.md (2840B)
1 # Sheepy
2 This is a sheepy package for [sheepy](https://spartatek.se/r/sheepy/file/README.md.html) and using [libsheepy](https://spartatek.se/r/libsheepy/file/README.md.html)
3
4 # netSerial
5
6 netSerial is a serializer/deserializer for JSON data structures that has compact binary format.
7
8 In general, it gives smaller bitstreams than JSON strings and smallJson serializer bitstream.
9
10 The netSerial serializer is in average 1.5 times slower than the smallJson serializer.
11
12 # Usage
13
14 Install with spm: `spm install netSerial`
15
16 Include netSerial: `#include "shpPackages/netSerial/netSerial.h"`, then:
17
18 ```c
19 // create a netSerial object:
20 createNetSerial(n);
21
22 // create a JSON
23 parseG(&n, "[3,270,-86942]");
24
25 smallBytest *bitstream = serialG(&n);
26 ```
27
28 # Encoding
29
30 Data types are encoded on 4 bits:
31 - undefined
32 - bool
33 - dict
34 - double
35 - varint
36 - string
37 - array
38 - bytes = faststring
39 - packed dict
40 - packed double
41 - packed varint
42 - packed string
43 - packed array
44 - packed bytes
45 - dict - all elements have same type
46 - array - all elements have same type
47
48 Integers are encoded as varint (n <<1 ^ n >> 63, see [protobuf](https://developers.google.com/protocol-buffers/docs/encoding)) and lengths (array, dictionary) are encoded as varuint.
49
50 The integer _150_ is encoded as `0xc4 0x25`.
51
52 - 0xc_4_ is integer type
53 - 0x_c_4 are the first 3 bits in 150, bit 7 is set so next byte represents the 7 next bits in 150
54 - _0x25_ are last bits in 150
55
56 The encoding of `[3,270,-86942]` gives:
57 ```
58 0x4f - uniform array of varint elements
59 0x03 - 3 elements
60 0x06 - int 3
61 0x9c 0x04 - int 270
62 0xbb 0xce 0x0a - int -86942
63 ```
64
65 The arrays have 2 variants: normal and uniform.
66
67 Normal arrays have elements of any types whereas uniform arrays have only one type of elements.
68
69 For example, `[null,null,null]` is a uniform array of undefined values, encoded as:
70 ```
71 0x0f - uniform array of undefined(null) elements
72 0x03 - 3 elements
73 ```
74
75 undefined is a type without data, only the element count is needed to represent an array of null elements.
76
77 The bool type is encoded in 4bits type + 1 bit data and is packed by default:
78
79 ```
80 {"sdf":true,"0":null,"1":null,"2":true,"3":true}
81
82 0x52 - dictionary with 5 elements
83 0x73 0x64 0x66 0x00 - "sdf" string
84 0x71 - bool type and bool data for bool 1,2 and 3 (true)
85 0x30 0x00 - "0" string
86 0x00 - undefined 1 and 2
87 0x31 0x00 - "1" string
88 0x32 0x00 - "2" string
89 0x11 - bool type 2 and 3
90 0x33 0x00 - "3" string
91 ```
92
93 Encoding a dictionary and an array:
94 ```
95 {"a":[3,270,-86942]}
96
97 0xfe - uniform dictionary of uniform arrays
98 0x01 - 1 element
99 0x61 0x00 - "a" string
100 0x34 - int type and 3 elements
101 0x06 - int 3
102 0x9c 0x04 - int 270
103 0xbb 0xce 0x0a - int -86942
104 ```
105
106 -