1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
/*
* Copyright (C) 2024 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//! flag value query module defines the flag value file read from mapped bytes
use crate::{AconfigStorageError, FILE_VERSION};
use aconfig_storage_file::{flag_info::FlagInfoHeader, read_u8_from_bytes, FlagValueType};
use anyhow::anyhow;
/// Get flag attribute bitfield
pub fn find_flag_attribute(
buf: &[u8],
flag_type: FlagValueType,
flag_index: u32,
) -> Result<u8, AconfigStorageError> {
let interpreted_header = FlagInfoHeader::from_bytes(buf)?;
if interpreted_header.version > crate::FILE_VERSION {
return Err(AconfigStorageError::HigherStorageFileVersion(anyhow!(
"Cannot read storage file with a higher version of {} with lib version {}",
interpreted_header.version,
FILE_VERSION
)));
}
// get byte offset to the flag info
let mut head = match flag_type {
FlagValueType::Boolean => (interpreted_header.boolean_flag_offset + flag_index) as usize,
};
if head >= interpreted_header.file_size as usize {
return Err(AconfigStorageError::InvalidStorageFileOffset(anyhow!(
"Flag info offset goes beyond the end of the file."
)));
}
let val = read_u8_from_bytes(buf, &mut head)?;
Ok(val)
}
#[cfg(test)]
mod tests {
use super::*;
use aconfig_storage_file::{test_utils::create_test_flag_info_list, FlagInfoBit};
#[test]
// this test point locks down query if flag has server override
fn test_is_flag_sticky() {
let flag_info_list = create_test_flag_info_list().into_bytes();
for offset in 0..8 {
let attribute =
find_flag_attribute(&flag_info_list[..], FlagValueType::Boolean, offset).unwrap();
assert_eq!((attribute & FlagInfoBit::HasServerOverride as u8) != 0u8, false);
}
}
#[test]
// this test point locks down query if flag is readwrite
fn test_is_flag_readwrite() {
let flag_info_list = create_test_flag_info_list().into_bytes();
let baseline: Vec<bool> = vec![true, false, true, true, false, false, false, true];
for offset in 0..8 {
let attribute =
find_flag_attribute(&flag_info_list[..], FlagValueType::Boolean, offset).unwrap();
assert_eq!(
(attribute & FlagInfoBit::IsReadWrite as u8) != 0u8,
baseline[offset as usize]
);
}
}
#[test]
// this test point locks down query if flag has local override
fn test_flag_has_override() {
let flag_info_list = create_test_flag_info_list().into_bytes();
for offset in 0..8 {
let attribute =
find_flag_attribute(&flag_info_list[..], FlagValueType::Boolean, offset).unwrap();
assert_eq!((attribute & FlagInfoBit::HasLocalOverride as u8) != 0u8, false);
}
}
#[test]
// this test point locks down query beyond the end of boolean section
fn test_boolean_out_of_range() {
let flag_info_list = create_test_flag_info_list().into_bytes();
let error =
find_flag_attribute(&flag_info_list[..], FlagValueType::Boolean, 8).unwrap_err();
assert_eq!(
format!("{:?}", error),
"InvalidStorageFileOffset(Flag info offset goes beyond the end of the file.)"
);
}
#[test]
// this test point locks down query error when file has a higher version
fn test_higher_version_storage_file() {
let mut info_list = create_test_flag_info_list();
info_list.header.version = crate::FILE_VERSION + 1;
let flag_info = info_list.into_bytes();
let error = find_flag_attribute(&flag_info[..], FlagValueType::Boolean, 4).unwrap_err();
assert_eq!(
format!("{:?}", error),
format!(
"HigherStorageFileVersion(Cannot read storage file with a higher version of {} with lib version {})",
crate::FILE_VERSION + 1,
crate::FILE_VERSION
)
);
}
}
|
