1 /*
2 * %CopyrightBegin%
3 *
4 * Copyright Ericsson AB 2002-2017. All Rights Reserved.
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 *
18 * %CopyrightEnd%
19 */
20
21 #ifdef HAVE_CONFIG_H
22 # include "config.h"
23 #endif
24
25 #include "sys.h"
26 #include "erl_osenv.h"
27 #include "erl_sys_driver.h"
28 #include "erl_alloc.h"
29
30 static erts_osenv_t sysenv_global_env;
31 static erts_rwmtx_t sysenv_rwmtx;
32
33 static void import_initial_env(void);
34
erts_sys_env_init()35 void erts_sys_env_init() {
36 erts_rwmtx_init(&sysenv_rwmtx, "environ", NIL,
37 ERTS_LOCK_FLAGS_PROPERTY_STATIC | ERTS_LOCK_FLAGS_CATEGORY_GENERIC);
38
39 erts_osenv_init(&sysenv_global_env);
40 import_initial_env();
41 }
42
erts_sys_rlock_global_osenv()43 const erts_osenv_t *erts_sys_rlock_global_osenv() {
44 erts_rwmtx_rlock(&sysenv_rwmtx);
45 return &sysenv_global_env;
46 }
47
erts_sys_rwlock_global_osenv()48 erts_osenv_t *erts_sys_rwlock_global_osenv() {
49 erts_rwmtx_rwlock(&sysenv_rwmtx);
50 return &sysenv_global_env;
51 }
52
erts_sys_runlock_global_osenv()53 void erts_sys_runlock_global_osenv() {
54 erts_rwmtx_runlock(&sysenv_rwmtx);
55 }
56
erts_sys_rwunlock_global_osenv()57 void erts_sys_rwunlock_global_osenv() {
58 erts_rwmtx_rwunlock(&sysenv_rwmtx);
59 }
60
erts_sys_explicit_host_getenv(char * key,char * value,size_t * size)61 int erts_sys_explicit_host_getenv(char *key, char *value, size_t *size) {
62 size_t new_size = GetEnvironmentVariableA(key, value, (DWORD)*size);
63
64 if(new_size == 0 && GetLastError() == ERROR_ENVVAR_NOT_FOUND) {
65 return 0;
66 } else if(new_size > *size) {
67 return -1;
68 }
69
70 *size = new_size;
71 return 1;
72 }
73
erts_sys_explicit_8bit_putenv(char * key,char * value)74 int erts_sys_explicit_8bit_putenv(char *key, char *value) {
75 WCHAR *wide_key, *wide_value;
76 int key_length, value_length;
77 int result;
78
79 /* Note that we do *NOT* honor the filename encoding flags (+fnu/+fnl)
80 * here; the previous implementation used SetEnvironmentVariableA and
81 * things may break if we step away from that. */
82
83 key_length = MultiByteToWideChar(CP_ACP, 0, key, -1, NULL, 0);
84 value_length = MultiByteToWideChar(CP_ACP, 0, value, -1, NULL, 0);
85
86 /* Report "not found" if either string isn't convertible. */
87 if(key_length == 0 || value_length == 0) {
88 return 0;
89 }
90
91 wide_key = erts_alloc(ERTS_ALC_T_TMP, key_length * sizeof(WCHAR));
92 wide_value = erts_alloc(ERTS_ALC_T_TMP, value_length * sizeof(WCHAR));
93
94 MultiByteToWideChar(CP_ACP, 0, key, -1, wide_key, key_length);
95 MultiByteToWideChar(CP_ACP, 0, value, -1, wide_value, value_length);
96
97 {
98 erts_osenv_data_t env_key, env_value;
99 erts_osenv_t *env;
100
101 env = erts_sys_rwlock_global_osenv();
102
103 /* -1 to exclude the NUL terminator. */
104 env_key.length = (key_length - 1) * sizeof(WCHAR);
105 env_key.data = wide_key;
106
107 env_value.length = (value_length - 1) * sizeof(WCHAR);
108 env_value.data = wide_value;
109
110 result = erts_osenv_put_native(env, &env_key, &env_value);
111 erts_sys_rwunlock_global_osenv();
112 }
113
114 erts_free(ERTS_ALC_T_TMP, wide_key);
115 erts_free(ERTS_ALC_T_TMP, wide_value);
116
117 return result;
118 }
119
erts_sys_explicit_8bit_getenv(char * key,char * value,size_t * size)120 int erts_sys_explicit_8bit_getenv(char *key, char *value, size_t *size) {
121 erts_osenv_data_t env_key, env_value;
122 int key_length, value_length, result;
123 WCHAR *wide_key, *wide_value;
124
125 key_length = MultiByteToWideChar(CP_ACP, 0, key, -1, NULL, 0);
126
127 /* Report "not found" if the string isn't convertible. */
128 if(key_length == 0) {
129 return 0;
130 }
131
132 wide_key = erts_alloc(ERTS_ALC_T_TMP, key_length * sizeof(WCHAR));
133 MultiByteToWideChar(CP_ACP, 0, key, -1, wide_key, key_length);
134
135 /* We assume that the worst possible size is twice the output buffer width,
136 * as we could theoretically be on a code page that requires surrogates. */
137 value_length = (*size) * 2;
138 wide_value = erts_alloc(ERTS_ALC_T_TMP, value_length * sizeof(WCHAR));
139
140 {
141 const erts_osenv_t *env = erts_sys_rlock_global_osenv();
142
143 /* -1 to exclude the NUL terminator. */
144 env_key.length = (key_length - 1) * sizeof(WCHAR);
145 env_key.data = wide_key;
146
147 env_value.length = value_length * sizeof(WCHAR);
148 env_value.data = wide_value;
149
150 result = erts_osenv_get_native(env, &env_key, &env_value);
151 erts_sys_runlock_global_osenv();
152 }
153
154 if(result == 1 && env_value.length > 0) {
155 /* This function doesn't NUL-terminate if the provided size is >= 0,
156 * so we pass (*size - 1) to reserve space for it and then do it
157 * manually. */
158 *size = WideCharToMultiByte(CP_ACP, 0, env_value.data,
159 env_value.length / sizeof(WCHAR), value, *size - 1, NULL, NULL);
160
161 if(*size == 0) {
162 if(GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
163 result = -1;
164 } else {
165 result = 0;
166 }
167 }
168 } else {
169 *size = 0;
170 }
171
172 if(*size > 0) {
173 value[*size] = '\0';
174 }
175
176 erts_free(ERTS_ALC_T_TMP, wide_key);
177 erts_free(ERTS_ALC_T_TMP, wide_value);
178
179 return result;
180 }
181
import_initial_env(void)182 static void import_initial_env(void) {
183 WCHAR *environment_block, *current_variable;
184
185 environment_block = GetEnvironmentStringsW();
186 current_variable = environment_block;
187
188 while(wcslen(current_variable) > 0) {
189 WCHAR *separator_index = wcschr(current_variable, L'=');
190
191 /* We tolerate environment variables starting with '=' as the per-drive
192 * working directories are stored this way. */
193 if(separator_index == current_variable) {
194 separator_index = wcschr(separator_index + 1, L'=');
195 }
196
197 if(separator_index != NULL && separator_index != current_variable) {
198 erts_osenv_data_t env_key, env_value;
199
200 env_key.length = (separator_index - current_variable) * sizeof(WCHAR);
201 env_key.data = current_variable;
202
203 env_value.length = (wcslen(separator_index) - 1) * sizeof(WCHAR);
204 env_value.data = separator_index + 1;
205
206 erts_osenv_put_native(&sysenv_global_env, &env_key, &env_value);
207 }
208
209 current_variable += wcslen(current_variable) + 1;
210 }
211
212 FreeEnvironmentStringsW(environment_block);
213 }
214