1 /*
2  * Copyright (C) 2006 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 // #define LOG_NDEBUG 0
19 
20 #include <stdlib.h>
21 #include <string.h>
22 #include <ctype.h>
23 #include <unistd.h>
24 #include <cutils/sockets.h>
25 #include <errno.h>
26 #include <assert.h>
27 
28 #include <cutils/properties.h>
29 #include <stdbool.h>
30 #include <inttypes.h>
31 #include <log/log.h>
32 
property_get_bool(const char * key,int8_t default_value)33 int8_t property_get_bool(const char *key, int8_t default_value) {
34     if (!key) {
35         return default_value;
36     }
37 
38     int8_t result = default_value;
39     char buf[PROPERTY_VALUE_MAX] = {'\0',};
40 
41     int len = property_get(key, buf, "");
42     if (len == 1) {
43         char ch = buf[0];
44         if (ch == '0' || ch == 'n') {
45             result = false;
46         } else if (ch == '1' || ch == 'y') {
47             result = true;
48         }
49     } else if (len > 1) {
50          if (!strcmp(buf, "no") || !strcmp(buf, "false") || !strcmp(buf, "off")) {
51             result = false;
52         } else if (!strcmp(buf, "yes") || !strcmp(buf, "true") || !strcmp(buf, "on")) {
53             result = true;
54         }
55     }
56 
57     return result;
58 }
59 
60 // Convert string property to int (default if fails); return default value if out of bounds
property_get_imax(const char * key,intmax_t lower_bound,intmax_t upper_bound,intmax_t default_value)61 static intmax_t property_get_imax(const char *key, intmax_t lower_bound, intmax_t upper_bound,
62         intmax_t default_value) {
63     if (!key) {
64         return default_value;
65     }
66 
67     intmax_t result = default_value;
68     char buf[PROPERTY_VALUE_MAX] = {'\0',};
69     char *end = NULL;
70 
71     int len = property_get(key, buf, "");
72     if (len > 0) {
73         int tmp = errno;
74         errno = 0;
75 
76         // Infer base automatically
77         result = strtoimax(buf, &end, /*base*/0);
78         if ((result == INTMAX_MIN || result == INTMAX_MAX) && errno == ERANGE) {
79             // Over or underflow
80             result = default_value;
81             ALOGV("%s(%s,%" PRIdMAX ") - overflow", __FUNCTION__, key, default_value);
82         } else if (result < lower_bound || result > upper_bound) {
83             // Out of range of requested bounds
84             result = default_value;
85             ALOGV("%s(%s,%" PRIdMAX ") - out of range", __FUNCTION__, key, default_value);
86         } else if (end == buf) {
87             // Numeric conversion failed
88             result = default_value;
89             ALOGV("%s(%s,%" PRIdMAX ") - numeric conversion failed",
90                     __FUNCTION__, key, default_value);
91         }
92 
93         errno = tmp;
94     }
95 
96     return result;
97 }
98 
property_get_int64(const char * key,int64_t default_value)99 int64_t property_get_int64(const char *key, int64_t default_value) {
100     return (int64_t)property_get_imax(key, INT64_MIN, INT64_MAX, default_value);
101 }
102 
property_get_int32(const char * key,int32_t default_value)103 int32_t property_get_int32(const char *key, int32_t default_value) {
104     return (int32_t)property_get_imax(key, INT32_MIN, INT32_MAX, default_value);
105 }
106 
107 #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
108 #include <sys/_system_properties.h>
109 
property_set(const char * key,const char * value)110 int property_set(const char *key, const char *value)
111 {
112     return __system_property_set(key, value);
113 }
114 
property_get(const char * key,char * value,const char * default_value)115 int property_get(const char *key, char *value, const char *default_value)
116 {
117     int len;
118 
119     len = __system_property_get(key, value);
120     if(len > 0) {
121         return len;
122     }
123     if(default_value) {
124         len = strlen(default_value);
125         if (len >= PROPERTY_VALUE_MAX) {
126             len = PROPERTY_VALUE_MAX - 1;
127         }
128         memcpy(value, default_value, len);
129         value[len] = '\0';
130     }
131     return len;
132 }
133 
134 struct property_list_callback_data
135 {
136     void (*propfn)(const char *key, const char *value, void *cookie);
137     void *cookie;
138 };
139 
property_list_callback(const prop_info * pi,void * cookie)140 static void property_list_callback(const prop_info *pi, void *cookie)
141 {
142     char name[PROP_NAME_MAX];
143     char value[PROP_VALUE_MAX];
144     struct property_list_callback_data *data = cookie;
145 
146     __system_property_read(pi, name, value);
147     data->propfn(name, value, data->cookie);
148 }
149 
property_list(void (* propfn)(const char * key,const char * value,void * cookie),void * cookie)150 int property_list(
151         void (*propfn)(const char *key, const char *value, void *cookie),
152         void *cookie)
153 {
154     struct property_list_callback_data data = { propfn, cookie };
155     return __system_property_foreach(property_list_callback, &data);
156 }
157