| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define TRACE_TAG RWX |
| |
| #include "adb_io.h" |
| |
| #include <unistd.h> |
| |
| #include <base/stringprintf.h> |
| |
| #include "adb_trace.h" |
| #include "adb_utils.h" |
| #include "sysdeps.h" |
| |
| bool SendProtocolString(int fd, const std::string& s) { |
| int length = s.size(); |
| if (length > 0xffff) { |
| length = 0xffff; |
| } |
| |
| // The cost of sending two strings outweighs the cost of formatting. |
| // "adb sync" performance is affected by this. |
| return WriteFdFmt(fd, "%04x%.*s", length, length, s.c_str()); |
| } |
| |
| bool ReadProtocolString(int fd, std::string* s, std::string* error) { |
| char buf[5]; |
| if (!ReadFdExactly(fd, buf, 4)) { |
| *error = perror_str("protocol fault (couldn't read status length)"); |
| return false; |
| } |
| buf[4] = 0; |
| |
| unsigned long len = strtoul(buf, 0, 16); |
| s->resize(len, '\0'); |
| if (!ReadFdExactly(fd, &(*s)[0], len)) { |
| *error = perror_str("protocol fault (couldn't read status message)"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool SendOkay(int fd) { |
| return WriteFdExactly(fd, "OKAY", 4); |
| } |
| |
| bool SendFail(int fd, const std::string& reason) { |
| return WriteFdExactly(fd, "FAIL", 4) && SendProtocolString(fd, reason); |
| } |
| |
| bool ReadFdExactly(int fd, void* buf, size_t len) { |
| char* p = reinterpret_cast<char*>(buf); |
| |
| size_t len0 = len; |
| |
| D("readx: fd=%d wanted=%zu", fd, len); |
| while (len > 0) { |
| int r = adb_read(fd, p, len); |
| if (r > 0) { |
| len -= r; |
| p += r; |
| } else if (r == -1) { |
| D("readx: fd=%d error %d: %s", fd, errno, strerror(errno)); |
| return false; |
| } else { |
| D("readx: fd=%d disconnected", fd); |
| errno = 0; |
| return false; |
| } |
| } |
| |
| VLOG(RWX) << "readx: fd=" << fd << " wanted=" << len0 << " got=" << (len0 - len) |
| << " " << dump_hex(reinterpret_cast<const unsigned char*>(buf), len0); |
| |
| return true; |
| } |
| |
| bool WriteFdExactly(int fd, const void* buf, size_t len) { |
| const char* p = reinterpret_cast<const char*>(buf); |
| int r; |
| |
| VLOG(RWX) << "writex: fd=" << fd << " len=" << len |
| << " " << dump_hex(reinterpret_cast<const unsigned char*>(buf), len); |
| |
| while (len > 0) { |
| r = adb_write(fd, p, len); |
| if (r == -1) { |
| D("writex: fd=%d error %d: %s", fd, errno, strerror(errno)); |
| if (errno == EAGAIN) { |
| adb_sleep_ms(1); // just yield some cpu time |
| continue; |
| } else if (errno == EPIPE) { |
| D("writex: fd=%d disconnected", fd); |
| errno = 0; |
| return false; |
| } else { |
| return false; |
| } |
| } else { |
| len -= r; |
| p += r; |
| } |
| } |
| return true; |
| } |
| |
| bool WriteFdExactly(int fd, const char* str) { |
| return WriteFdExactly(fd, str, strlen(str)); |
| } |
| |
| bool WriteFdExactly(int fd, const std::string& str) { |
| return WriteFdExactly(fd, str.c_str(), str.size()); |
| } |
| |
| bool WriteFdFmt(int fd, const char* fmt, ...) { |
| std::string str; |
| |
| va_list ap; |
| va_start(ap, fmt); |
| android::base::StringAppendV(&str, fmt, ap); |
| va_end(ap); |
| |
| return WriteFdExactly(fd, str); |
| } |
| |
| bool ReadOrderlyShutdown(int fd) { |
| char buf[16]; |
| |
| // Only call this function if you're sure that the peer does |
| // orderly/graceful shutdown of the socket, closing the socket so that |
| // adb_read() will return 0. If the peer keeps the socket open, adb_read() |
| // will never return. |
| int result = adb_read(fd, buf, sizeof(buf)); |
| if (result == -1) { |
| // If errno is EAGAIN, that means this function was called on a |
| // nonblocking socket and it would have blocked (which would be bad |
| // because we'd probably block the main thread where nonblocking IO is |
| // done). Don't do that. If you have a nonblocking socket, use the |
| // fdevent APIs to get called on FDE_READ, and then call this function |
| // if you really need to, but it shouldn't be needed for server sockets. |
| CHECK_NE(errno, EAGAIN); |
| |
| // Note that on Windows, orderly shutdown sometimes causes |
| // recv() == SOCKET_ERROR && WSAGetLastError() == WSAECONNRESET. That |
| // can be ignored. |
| return false; |
| } else if (result == 0) { |
| // Peer has performed an orderly/graceful shutdown. |
| return true; |
| } else { |
| // Unexpectedly received data. This is essentially a protocol error |
| // because you should not call this function unless you expect no more |
| // data. We don't repeatedly call adb_read() until we get zero because |
| // we don't know how long that would take, but we do know that the |
| // caller wants to close the socket soon. |
| VLOG(RWX) << "ReadOrderlyShutdown(" << fd << ") unexpectedly read " |
| << dump_hex(buf, result); |
| // Shutdown the socket to prevent the caller from reading or writing to |
| // it which doesn't make sense if we just read and discarded some data. |
| adb_shutdown(fd); |
| errno = EINVAL; |
| return false; |
| } |
| } |