1 /*
2 * Copyright (c) 2016 Catalysts GmbH
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 #include <fstream>
17 #include <sstream>
18
19 #include "common.h"
20 #include "vendor/tinyformat.hpp"
21
22 namespace ebpf {
23
read_cpu_range(std::string path)24 std::vector<int> read_cpu_range(std::string path) {
25 std::ifstream cpus_range_stream { path };
26 std::vector<int> cpus;
27 std::string cpu_range;
28
29 while (std::getline(cpus_range_stream, cpu_range, ',')) {
30 std::size_t rangeop = cpu_range.find('-');
31 if (rangeop == std::string::npos) {
32 cpus.push_back(std::stoi(cpu_range));
33 }
34 else {
35 int start = std::stoi(cpu_range.substr(0, rangeop));
36 int end = std::stoi(cpu_range.substr(rangeop + 1));
37 for (int i = start; i <= end; i++)
38 cpus.push_back(i);
39 }
40 }
41 return cpus;
42 }
43
get_online_cpus()44 std::vector<int> get_online_cpus() {
45 return read_cpu_range("/sys/devices/system/cpu/online");
46 }
47
get_possible_cpus()48 std::vector<int> get_possible_cpus() {
49 return read_cpu_range("/sys/devices/system/cpu/possible");
50 }
51
get_pid_exe(pid_t pid)52 std::string get_pid_exe(pid_t pid) {
53 char exe_path[4096];
54 int res;
55
56 std::string exe_link = tfm::format("/proc/%d/exe", pid);
57 res = readlink(exe_link.c_str(), exe_path, sizeof(exe_path));
58 if (res == -1)
59 return "";
60 if (res >= sizeof(exe_path))
61 res = sizeof(exe_path) - 1;
62 exe_path[res] = '\0';
63 return std::string(exe_path);
64 }
65
66 } // namespace ebpf
67