1/*
2 * Copyright (C) 2015 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 <fstream>
18#include <iostream>
19#include <string>
20#include <vector>
21
22#include <errno.h>
23#include <time.h>
24#include <unistd.h>
25
26using std::cerr;
27using std::cout;
28using std::endl;
29using std::getline;
30using std::ifstream;
31using std::string;
32using std::vector;
33
34namespace {
35
36bool ReadLines(const string& input_file_path, vector<string>* lines) {
37  ifstream watched_file(input_file_path);
38  if (!watched_file.is_open()) {
39    cerr << "Unable to open input file: " << input_file_path << endl;
40    return false;
41  }
42
43  string line;
44  while (getline(watched_file, line)) {
45    lines->push_back(line);
46  }
47  watched_file.close();
48  return true;
49}
50
51bool HasSentinel(const vector<string>& lines, const string& sentinel) {
52  for (const auto& line : lines) {
53    if (line.find(sentinel) != string::npos) {
54      return true;
55    }
56  }
57  return false;
58}
59
60}  // namespace
61
62int main(int argc, const char* argv[]) {
63  if (argc != 5) {
64    cerr << "Invalid usage." << endl;
65    cerr << argv[0]
66         << " <timeout in seconds>"
67         << " <input file path>"
68         << " <success sentinel>"
69         << " <failure sentinel>" << endl;
70    return -EINVAL;
71  }
72  const string timeout_as_str = argv[1];
73  const string input_file_path = argv[2];
74  const string success_sentinel = argv[3];
75  const string failure_sentinel = argv[4];
76
77  const int timeout_seconds = atoi(timeout_as_str.c_str());
78  if (timeout_seconds <= 0) {
79    cerr << "Invalid timeout value (in seconds): " << timeout_as_str << endl;
80    return -EINVAL;
81  }
82
83  int exit_code = 1;
84  const time_t start_time = time(nullptr);
85  vector<string> lines;
86  while (true) {
87    sleep(1);
88    if (time(nullptr) - start_time > timeout_seconds) {
89      cerr << "Timed out waiting for success/failure sentinel." << endl;
90      break;
91    }
92    // Ignore errors when reading lines.  The file may not immediately exist
93    // because it takes the Java process some time to create it.
94    lines.clear();
95    ReadLines(input_file_path, &lines);
96
97    if (HasSentinel(lines, success_sentinel)) {
98      exit_code = 0;
99      break;
100    }
101    if (HasSentinel(lines, failure_sentinel)) {
102      break;
103    }
104  }
105
106  cout << "Found output:" << endl;
107  for (const auto& line : lines) {
108    cout << "  " << line << endl;
109  }
110  return exit_code;
111}
112