1ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal/* 2ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * Copyright (C) 2016 The Android Open Source Project 3ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * 4ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * Licensed under the Apache License, Version 2.0 (the "License"); 5ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * you may not use this file except in compliance with the License. 6ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * You may obtain a copy of the License at 7ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * 8ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * http://www.apache.org/licenses/LICENSE-2.0 9ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * 10ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * Unless required by applicable law or agreed to in writing, software 11ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * distributed under the License is distributed on an "AS IS" BASIS, 12ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * See the License for the specific language governing permissions and 14ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal * limitations under the License. 15ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal */ 16ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 17ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal#include <algorithm> 18960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal#include <cerrno> 19ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal#include <cstdint> 20960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal#include <cstring> 21ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 22ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal#include "android-base/logging.h" 23ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 24ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal#include "wifilogd/local_utils.h" 25ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal#include "wifilogd/os.h" 26ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 27ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalnamespace android { 28ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalnamespace wifilogd { 29ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 30ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalusing local_utils::GetMaxVal; 31ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 32ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalnamespace { 33ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalconstexpr auto kMaxNanoSeconds = 1000 * 1000 * 1000 - 1; 34ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal} 35ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 36a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawalconstexpr int Os::kInvalidFd; 37a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal 38ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalOs::Os() : raw_os_(new RawOs()) {} 39ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalOs::Os(std::unique_ptr<RawOs> raw_os) : raw_os_(std::move(raw_os)) {} 40ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalOs::~Os() {} 41ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 42a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawalstd::tuple<int, Os::Errno> Os::GetControlSocket( 43a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal const std::string& socket_name) { 44a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal int sock_fd = raw_os_->GetControlSocket(socket_name.c_str()); 45a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal if (sock_fd < 0) { 46a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal return {kInvalidFd, errno}; 47a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal } else { 48a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal return {sock_fd, 0}; 49a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal } 50a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal} 51a5bb08c1cf8a8d1ff097fa7a050d7787e9821c6amukesh agrawal 52ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawalOs::Timestamp Os::GetTimestamp(clockid_t clock_id) const { 53ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal struct timespec now_timespec; 54ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal int failed = raw_os_->ClockGettime(clock_id, &now_timespec); 55ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal if (failed) { 56ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal LOG(FATAL) << "Unexpected error: " << std::strerror(errno); 57ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal } 58ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal CHECK(now_timespec.tv_nsec <= kMaxNanoSeconds); 59ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 60ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal Timestamp now_timestamp; 61ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal now_timestamp.secs = SAFELY_CLAMP( 62ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal now_timespec.tv_sec, uint32_t, 0, 63ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal // The upper-bound comes from the source-type on 32-bit platforms, 64ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal // and the dest-type on 64-bit platforms. Using min(), we can figure out 65ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal // which type to use for the upper bound, without resorting to macros. 66ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal std::min(static_cast<uintmax_t>(GetMaxVal(now_timestamp.secs)), 67ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal static_cast<uintmax_t>(GetMaxVal(now_timespec.tv_sec)))); 68ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal now_timestamp.nsecs = 69ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal SAFELY_CLAMP(now_timespec.tv_nsec, uint32_t, 0, kMaxNanoSeconds); 70ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal return now_timestamp; 71ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal} 72ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal 73960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawalvoid Os::Nanosleep(uint32_t sleep_time_nsec) { 74960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal struct timespec sleep_timespec = { 75960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal 0, // tv_sec 76960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal SAFELY_CLAMP(sleep_time_nsec, decltype(timespec::tv_nsec), 0, kMaxNanos)}; 77960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal 78960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal int failed = 0; 79960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal do { 80960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal struct timespec remaining_timespec; 81960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal failed = raw_os_->Nanosleep(&sleep_timespec, &remaining_timespec); 82960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal sleep_timespec = remaining_timespec; 83960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal } while (failed && errno == EINTR && sleep_timespec.tv_nsec > 0); 84960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal 85960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal if (failed && errno != EINTR) { 86960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal // The only other documented errors for the underlying nanosleep() call are 87960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal // EFAULT and EINVAL. But we always pass valid pointers, and the values in 88960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal // |sleep_timespec| are always valid. 89960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal LOG(FATAL) << "Unexpected error: " << std::strerror(errno); 90960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal } 91960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal} 92960c8a88c83c55c21a3286628591a41d2fb42231mukesh agrawal 93d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawalstd::tuple<size_t, Os::Errno> Os::ReceiveDatagram(int fd, void* buf, 94d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal size_t buflen) { 95d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // recv() takes a size_t, but returns an ssize_t. That means that the largest 96d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // successful read that recv() can report is the maximal ssize_t. Passing a 97d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // larger |buflen| risks mistakenly reporting a truncated read. 98d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal CHECK(buflen <= GetMaxVal<ssize_t>()); 99d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal 100d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal const ssize_t res = raw_os_->Recv(fd, buf, buflen, MSG_TRUNC); 101d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal if (res < 0) { 102d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal return {0, errno}; 103d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal } 104d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal 105d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // Due to the MSG_TRUNC flag, |res| may reasonably be larger than 106d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // |buflen|. In such cases, |res| indicates the full size of the datagram, 107d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // before being truncated to fit our buffer. Hence, we omit the 108d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal // buffer-overflow CHECK that exists in Write(). 109d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal return {res, 0}; 110d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal} 111d75fd9e9b73995a6303ae99977ab1baf9db9b42fmukesh agrawal 112b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawalstd::tuple<size_t, Os::Errno> Os::Write(int fd, const void* buf, 113b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal size_t buflen) { 114b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // write() takes a size_t, but returns an ssize_t. That means that the 115b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // largest successful write that write() can report is the maximal ssize_t. 116b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // Passing a larger |buflen| risks mistakenly reporting a truncated write. 117b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal CHECK(buflen <= GetMaxVal<ssize_t>()); 118b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal 119b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal const ssize_t res = raw_os_->Write(fd, buf, buflen); 120b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal if (res < 0) { 121b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal return {0, errno}; 122b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal } 123b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal 124b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal CHECK(res <= 125b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal SAFELY_CLAMP(buflen, ssize_t, 0, 126b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal GetMaxVal<ssize_t>())); // Abort on buffer overflow. 127b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal 128b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // Note that |res| may be less than buflen. However, a) a short write is 129b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // not an error, and b) |errno| may be stale, as |errno| is only guaranteed to 130b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // be set if an error occurred. Hence, we return Errno of 0 unconditionally. 131b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal // See http://yarchive.net/comp/linux/write_error_return.html 132b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal return {res, 0}; 133b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal} 134b8f8f6ab38fe147fa7aed5cdd9f9ce0e5a3a2e2fmukesh agrawal 135ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal} // namespace wifilogd 136ec533e0f59b7e88bac734d538f596ab095bc74camukesh agrawal} // namespace android 137