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 <errno.h>
21 #include <string.h>
22 #include <unistd.h>
23
24 #include <string>
25
26 #ifndef RS_COMPATIBILITY_LIB
27 #include <sys/wait.h>
28 #endif
29
30
31 namespace android {
32 namespace renderscript {
33
rsuCopyString(const char * name)34 const char * rsuCopyString(const char *name) {
35 return rsuCopyString(name, strlen(name));
36 }
37
rsuCopyString(const char * name,size_t len)38 const char * rsuCopyString(const char *name, size_t len) {
39 char *n = new char[len+1];
40 memcpy(n, name, len);
41 n[len] = 0;
42 return n;
43 }
44
rsuJoinStrings(int n,const char * const * strs)45 const char* rsuJoinStrings(int n, const char* const* strs) {
46 std::string tmp;
47 for (int i = 0; i < n; i++) {
48 if (i > 0) {
49 tmp.append(" ");
50 }
51 tmp.append(strs[i]);
52 }
53 return strndup(tmp.c_str(), tmp.size());
54 }
55
56 #ifndef RS_COMPATIBILITY_LIB
rsuExecuteCommand(const char * exe,int nArgs,const char * const * args)57 bool rsuExecuteCommand(const char *exe, int nArgs, const char * const *args) {
58 std::unique_ptr<const char> joined(rsuJoinStrings(nArgs, args));
59 ALOGV("Invoking %s with args '%s'", exe, joined.get());
60
61 pid_t pid = fork();
62
63 switch (pid) {
64 case -1: { // Error occurred (we attempt no recovery)
65 ALOGE("Fork of \"%s\" failed with error %s", exe, strerror(errno));
66 return false;
67 }
68 case 0: { // Child process
69 // No (direct or indirect) call to malloc between fork and exec. It is
70 // possible that a different thread holds the heap lock before the fork.
71
72 // ProcessManager in libcore can reap unclaimed SIGCHLDs in its process
73 // group. To ensure that the exit signal is not caught by
74 // ProcessManager and instead sent to libRS, set the child's PGID to its
75 // PID.
76 setpgid(0, 0);
77
78 execv(exe, (char * const *)args);
79
80 ALOGE("execv() failed: %s", strerror(errno));
81 abort();
82 return false;
83 }
84 default: { // Parent process (actual driver)
85 // Wait on child process to finish execution.
86 int status = 0;
87 pid_t w = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
88 if (w == -1) {
89 ALOGE("Waitpid of \"%s\" failed with error %s", exe,
90 strerror(errno));
91 return false;
92 }
93
94 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
95 return true;
96 }
97
98 ALOGE("Child process \"%s\" terminated with status %d", exe, status);
99 return false;
100 }
101 }
102 }
103 #endif // RS_COMPATIBILITY_LIB
104
105 // Implementation of property_get from libcutils
property_get(const char * key,char * value,const char * default_value)106 int property_get(const char *key, char *value, const char *default_value) {
107 int len;
108 len = __system_property_get(key, value);
109 if (len > 0) {
110 return len;
111 }
112
113 if (default_value) {
114 len = strlen(default_value);
115 memcpy(value, default_value, len + 1);
116 }
117 return len;
118 }
119
120 } // namespace renderscript
121 } // namespace android
122