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 #include <cutils/properties.h>
18
19 #define LOG_TAG "properties"
20 // #define LOG_NDEBUG 0
21
22 #include <assert.h>
23 #include <ctype.h>
24 #include <errno.h>
25 #include <inttypes.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29
30 #include <cutils/sockets.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", __FUNCTION__, key,
90 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 return __system_property_set(key, value);
112 }
113
property_get(const char * key,char * value,const char * default_value)114 int property_get(const char *key, char *value, const char *default_value) {
115 int len = __system_property_get(key, value);
116 if (len > 0) {
117 return len;
118 }
119 if (default_value) {
120 len = strnlen(default_value, PROPERTY_VALUE_MAX - 1);
121 memcpy(value, default_value, len);
122 value[len] = '\0';
123 }
124 return len;
125 }
126
127 struct callback_data {
128 void (*callback)(const char* name, const char* value, void* cookie);
129 void* cookie;
130 };
131
trampoline(void * raw_data,const char * name,const char * value,unsigned)132 static void trampoline(void* raw_data, const char* name, const char* value, unsigned /*serial*/) {
133 callback_data* data = reinterpret_cast<callback_data*>(raw_data);
134 data->callback(name, value, data->cookie);
135 }
136
property_list_callback(const prop_info * pi,void * data)137 static void property_list_callback(const prop_info* pi, void* data) {
138 __system_property_read_callback(pi, trampoline, data);
139 }
140
property_list(void (* fn)(const char * name,const char * value,void * cookie),void * cookie)141 int property_list(void (*fn)(const char* name, const char* value, void* cookie), void* cookie) {
142 callback_data data = { fn, cookie };
143 return __system_property_foreach(property_list_callback, &data);
144 }
145