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
31namespace android {
32namespace renderscript {
33
34const char * rsuCopyString(const char *name) {
35    return rsuCopyString(name, strlen(name));
36}
37
38const 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
45const 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
57bool 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
106int 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