1 /*
2 * Copyright (C) 2013 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 "rsUtils.h"
18 #include "rsCppUtils.h"
19
20 #include <string>
21 #include <unistd.h>
22
23 #ifndef RS_COMPATIBILITY_LIB
24 #include <sys/wait.h>
25 #endif
26
27
28 namespace android {
29 namespace renderscript {
30
rsuCopyString(const char * name)31 const char * rsuCopyString(const char *name) {
32 return rsuCopyString(name, strlen(name));
33 }
34
rsuCopyString(const char * name,size_t len)35 const char * rsuCopyString(const char *name, size_t len) {
36 char *n = new char[len+1];
37 memcpy(n, name, len);
38 n[len] = 0;
39 return n;
40 }
41
rsuJoinStrings(int n,const char * const * strs)42 const char* rsuJoinStrings(int n, const char* const* strs) {
43 std::string tmp;
44 for (int i = 0; i < n; i++) {
45 if (i > 0) {
46 tmp.append(" ");
47 }
48 tmp.append(strs[i]);
49 }
50 return strndup(tmp.c_str(), tmp.size());
51 }
52
53 #ifndef RS_COMPATIBILITY_LIB
rsuExecuteCommand(const char * exe,int nArgs,const char * const * args)54 bool rsuExecuteCommand(const char *exe, int nArgs, const char * const *args) {
55 std::unique_ptr<const char> joined(rsuJoinStrings(nArgs, args));
56 ALOGV("Invoking %s with args '%s'", exe, joined.get());
57
58 pid_t pid = fork();
59
60 switch (pid) {
61 case -1: { // Error occurred (we attempt no recovery)
62 ALOGE("Fork of \"%s\" failed with error %s", exe, strerror(errno));
63 return false;
64 }
65 case 0: { // Child process
66 // No (direct or indirect) call to malloc between fork and exec. It is
67 // possible that a different thread holds the heap lock before the fork.
68
69 // ProcessManager in libcore can reap unclaimed SIGCHLDs in its process
70 // group. To ensure that the exit signal is not caught by
71 // ProcessManager and instead sent to libRS, set the child's PGID to its
72 // PID.
73 setpgid(0, 0);
74
75 execv(exe, (char * const *)args);
76
77 ALOGE("execv() failed: %s", strerror(errno));
78 abort();
79 return false;
80 }
81 default: { // Parent process (actual driver)
82 // Wait on child process to finish execution.
83 int status = 0;
84 pid_t w = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
85 if (w == -1) {
86 ALOGE("Waitpid of \"%s\" failed with error %s", exe,
87 strerror(errno));
88 return false;
89 }
90
91 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
92 return true;
93 }
94
95 ALOGE("Child process \"%s\" terminated with status %d", exe, status);
96 return false;
97 }
98 }
99 }
100 #endif // RS_COMPATIBILITY_LIB
101
102 // Implementation of property_get from libcutils
property_get(const char * key,char * value,const char * default_value)103 int property_get(const char *key, char *value, const char *default_value) {
104 int len;
105 len = __system_property_get(key, value);
106 if (len > 0) {
107 return len;
108 }
109
110 if (default_value) {
111 len = strlen(default_value);
112 memcpy(value, default_value, len + 1);
113 }
114 return len;
115 }
116
117 } // namespace renderscript
118 } // namespace android
119