1 //
2 // Copyright 2016 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16
17 #define LOG_TAG "properties"
18
19 #include <ctype.h>
20 #include <stdbool.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24
25 #include <cutils/properties.h>
26 #include <log/log.h>
27
28 static const int MAX_PROPERTIES = 5;
29
30 struct property {
31 char key[PROP_KEY_MAX + 2];
32 char value[PROP_VALUE_MAX + 2];
33 };
34
35 int num_properties = 0;
36 struct property properties[MAX_PROPERTIES];
37
38 // Find the correct entry.
property_find(const char * key)39 static int property_find(const char* key) {
40 for (int i = 0; i < num_properties; i++) {
41 if (strncmp(properties[i].key, key, PROP_KEY_MAX) == 0) {
42 return i;
43 }
44 }
45 return MAX_PROPERTIES;
46 }
47
property_set(const char * key,const char * value)48 int property_set(const char* key, const char* value) {
49 if (strnlen(value, PROP_VALUE_MAX) > PROP_VALUE_MAX) return -1;
50
51 // Check to see if the property exists.
52 int prop_index = property_find(key);
53
54 if (prop_index == MAX_PROPERTIES) {
55 if (num_properties >= MAX_PROPERTIES) return -1;
56 prop_index = num_properties;
57 num_properties += 1;
58 }
59
60 // This is test code. Be nice and don't push the boundary cases!
61 strncpy(properties[prop_index].key, key, PROP_KEY_MAX + 1);
62 strncpy(properties[prop_index].value, value, PROP_VALUE_MAX + 1);
63 return 0;
64 }
65
property_get(const char * key,char * value,const char * default_value)66 int property_get(const char* key, char* value, const char* default_value) {
67 // This doesn't mock the behavior of default value
68 if (default_value != NULL) ALOGE("%s: default_value is ignored!", __func__);
69
70 // Check to see if the property exists.
71 int prop_index = property_find(key);
72
73 if (prop_index == MAX_PROPERTIES) return 0;
74
75 int len = strlen(properties[prop_index].value);
76 memcpy(value, properties[prop_index].value, len);
77 value[len] = '\0';
78 return len;
79 }
80