lldb/source/Host/common/Terminal.cpp

   1 //===-- Terminal.cpp ------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "lldb/Host/Terminal.h"
  10
  11 #include "lldb/Host/Config.h"
  12 #include "lldb/Host/PosixApi.h"
  13 #include "llvm/ADT/STLExtras.h"
  14
  15 #include <csignal>
  16 #include <fcntl.h>
  17 #include <optional>
  18
  19 #if LLDB_ENABLE_TERMIOS
  20 #include <termios.h>
  21 #endif
  22
  23 using namespace lldb_private;
  24
  25 struct Terminal::Data {
  26 #if LLDB_ENABLE_TERMIOS
  27   struct termios m_termios; ///< Cached terminal state information.
  28 #endif
  29 };
  30
  31 bool Terminal::IsATerminal() const { return m_fd >= 0 && ::isatty(m_fd); }
  32
  33 #if !LLDB_ENABLE_TERMIOS
  34 static llvm::Error termiosMissingError() {
  35   return llvm::createStringError(llvm::inconvertibleErrorCode(),
  36                                  "termios support missing in LLDB");
  37 }
  38 #endif
  39
  40 llvm::Expected<Terminal::Data> Terminal::GetData() {
  41 #if LLDB_ENABLE_TERMIOS
  42   if (!FileDescriptorIsValid())
  43     return llvm::createStringError(llvm::inconvertibleErrorCode(),
  44                                    "invalid fd");
  45
  46   if (!IsATerminal())
  47     return llvm::createStringError(llvm::inconvertibleErrorCode(),
  48                                    "fd not a terminal");
  49
  50   Data data;
  51   if (::tcgetattr(m_fd, &data.m_termios) != 0)
  52     return llvm::createStringError(
  53         std::error_code(errno, std::generic_category()),
  54         "unable to get teletype attributes");
  55   return data;
  56 #else // !LLDB_ENABLE_TERMIOS
  57   return termiosMissingError();
  58 #endif // LLDB_ENABLE_TERMIOS
  59 }
  60
  61 llvm::Error Terminal::SetData(const Terminal::Data &data) {
  62 #if LLDB_ENABLE_TERMIOS
  63   assert(FileDescriptorIsValid());
  64   assert(IsATerminal());
  65
  66   if (::tcsetattr(m_fd, TCSANOW, &data.m_termios) != 0)
  67     return llvm::createStringError(
  68         std::error_code(errno, std::generic_category()),
  69         "unable to set teletype attributes");
  70   return llvm::Error::success();
  71 #else // !LLDB_ENABLE_TERMIOS
  72   return termiosMissingError();
  73 #endif // LLDB_ENABLE_TERMIOS
  74 }
  75
  76 llvm::Error Terminal::SetEcho(bool enabled) {
  77 #if LLDB_ENABLE_TERMIOS
  78   llvm::Expected<Data> data = GetData();
  79   if (!data)
  80     return data.takeError();
  81
  82   struct termios &fd_termios = data->m_termios;
  83   fd_termios.c_lflag &= ~ECHO;
  84   if (enabled)
  85     fd_termios.c_lflag |= ECHO;
  86   return SetData(data.get());
  87 #else // !LLDB_ENABLE_TERMIOS
  88   return termiosMissingError();
  89 #endif // LLDB_ENABLE_TERMIOS
  90 }
  91
  92 llvm::Error Terminal::SetCanonical(bool enabled) {
  93 #if LLDB_ENABLE_TERMIOS
  94   llvm::Expected<Data> data = GetData();
  95   if (!data)
  96     return data.takeError();
  97
  98   struct termios &fd_termios = data->m_termios;
  99   fd_termios.c_lflag &= ~ICANON;
 100   if (enabled)
 101     fd_termios.c_lflag |= ICANON;
 102   return SetData(data.get());
 103 #else // !LLDB_ENABLE_TERMIOS
 104   return termiosMissingError();
 105 #endif // LLDB_ENABLE_TERMIOS
 106 }
 107
 108 llvm::Error Terminal::SetRaw() {
 109 #if LLDB_ENABLE_TERMIOS
 110   llvm::Expected<Data> data = GetData();
 111   if (!data)
 112     return data.takeError();
 113
 114   struct termios &fd_termios = data->m_termios;
 115   ::cfmakeraw(&fd_termios);
 116
 117   // Make sure only one character is needed to return from a read
 118   // (cfmakeraw() doesn't do this on NetBSD)
 119   fd_termios.c_cc[VMIN] = 1;
 120   fd_termios.c_cc[VTIME] = 0;
 121
 122   return SetData(data.get());
 123 #else // !LLDB_ENABLE_TERMIOS
 124   return termiosMissingError();
 125 #endif // LLDB_ENABLE_TERMIOS
 126 }
 127
 128 #if LLDB_ENABLE_TERMIOS
 129 static std::optional<speed_t> baudRateToConst(unsigned int baud_rate) {
 130   switch (baud_rate) {
 131 #if defined(B50)
 132   case 50:
 133     return B50;
 134 #endif
 135 #if defined(B75)
 136   case 75:
 137     return B75;
 138 #endif
 139 #if defined(B110)
 140   case 110:
 141     return B110;
 142 #endif
 143 #if defined(B134)
 144   case 134:
 145     return B134;
 146 #endif
 147 #if defined(B150)
 148   case 150:
 149     return B150;
 150 #endif
 151 #if defined(B200)
 152   case 200:
 153     return B200;
 154 #endif
 155 #if defined(B300)
 156   case 300:
 157     return B300;
 158 #endif
 159 #if defined(B600)
 160   case 600:
 161     return B600;
 162 #endif
 163 #if defined(B1200)
 164   case 1200:
 165     return B1200;
 166 #endif
 167 #if defined(B1800)
 168   case 1800:
 169     return B1800;
 170 #endif
 171 #if defined(B2400)
 172   case 2400:
 173     return B2400;
 174 #endif
 175 #if defined(B4800)
 176   case 4800:
 177     return B4800;
 178 #endif
 179 #if defined(B9600)
 180   case 9600:
 181     return B9600;
 182 #endif
 183 #if defined(B19200)
 184   case 19200:
 185     return B19200;
 186 #endif
 187 #if defined(B38400)
 188   case 38400:
 189     return B38400;
 190 #endif
 191 #if defined(B57600)
 192   case 57600:
 193     return B57600;
 194 #endif
 195 #if defined(B115200)
 196   case 115200:
 197     return B115200;
 198 #endif
 199 #if defined(B230400)
 200   case 230400:
 201     return B230400;
 202 #endif
 203 #if defined(B460800)
 204   case 460800:
 205     return B460800;
 206 #endif
 207 #if defined(B500000)
 208   case 500000:
 209     return B500000;
 210 #endif
 211 #if defined(B576000)
 212   case 576000:
 213     return B576000;
 214 #endif
 215 #if defined(B921600)
 216   case 921600:
 217     return B921600;
 218 #endif
 219 #if defined(B1000000)
 220   case 1000000:
 221     return B1000000;
 222 #endif
 223 #if defined(B1152000)
 224   case 1152000:
 225     return B1152000;
 226 #endif
 227 #if defined(B1500000)
 228   case 1500000:
 229     return B1500000;
 230 #endif
 231 #if defined(B2000000)
 232   case 2000000:
 233     return B2000000;
 234 #endif
 235 #if defined(B76800)
 236   case 76800:
 237     return B76800;
 238 #endif
 239 #if defined(B153600)
 240   case 153600:
 241     return B153600;
 242 #endif
 243 #if defined(B307200)
 244   case 307200:
 245     return B307200;
 246 #endif
 247 #if defined(B614400)
 248   case 614400:
 249     return B614400;
 250 #endif
 251 #if defined(B2500000)
 252   case 2500000:
 253     return B2500000;
 254 #endif
 255 #if defined(B3000000)
 256   case 3000000:
 257     return B3000000;
 258 #endif
 259 #if defined(B3500000)
 260   case 3500000:
 261     return B3500000;
 262 #endif
 263 #if defined(B4000000)
 264   case 4000000:
 265     return B4000000;
 266 #endif
 267   default:
 268     return std::nullopt;
 269   }
 270 }
 271 #endif
 272
 273 llvm::Error Terminal::SetBaudRate(unsigned int baud_rate) {
 274 #if LLDB_ENABLE_TERMIOS
 275   llvm::Expected<Data> data = GetData();
 276   if (!data)
 277     return data.takeError();
 278
 279   struct termios &fd_termios = data->m_termios;
 280   std::optional<speed_t> val = baudRateToConst(baud_rate);
 281   if (!val) // invalid value
 282     return llvm::createStringError(llvm::inconvertibleErrorCode(),
 283                                    "baud rate %d unsupported by the platform",
 284                                    baud_rate);
 285   if (::cfsetispeed(&fd_termios, *val) != 0)
 286     return llvm::createStringError(
 287         std::error_code(errno, std::generic_category()),
 288         "setting input baud rate failed");
 289   if (::cfsetospeed(&fd_termios, *val) != 0)
 290     return llvm::createStringError(
 291         std::error_code(errno, std::generic_category()),
 292         "setting output baud rate failed");
 293   return SetData(data.get());
 294 #else // !LLDB_ENABLE_TERMIOS
 295   return termiosMissingError();
 296 #endif // LLDB_ENABLE_TERMIOS
 297 }
 298
 299 llvm::Error Terminal::SetStopBits(unsigned int stop_bits) {
 300 #if LLDB_ENABLE_TERMIOS
 301   llvm::Expected<Data> data = GetData();
 302   if (!data)
 303     return data.takeError();
 304
 305   struct termios &fd_termios = data->m_termios;
 306   switch (stop_bits) {
 307   case 1:
 308     fd_termios.c_cflag &= ~CSTOPB;
 309     break;
 310   case 2:
 311     fd_termios.c_cflag |= CSTOPB;
 312     break;
 313   default:
 314     return llvm::createStringError(
 315         llvm::inconvertibleErrorCode(),
 316         "invalid stop bit count: %d (must be 1 or 2)", stop_bits);
 317   }
 318   return SetData(data.get());
 319 #else // !LLDB_ENABLE_TERMIOS
 320   return termiosMissingError();
 321 #endif // LLDB_ENABLE_TERMIOS
 322 }
 323
 324 llvm::Error Terminal::SetParity(Terminal::Parity parity) {
 325 #if LLDB_ENABLE_TERMIOS
 326   llvm::Expected<Data> data = GetData();
 327   if (!data)
 328     return data.takeError();
 329
 330   struct termios &fd_termios = data->m_termios;
 331   fd_termios.c_cflag &= ~(
 332 #if defined(CMSPAR)
 333       CMSPAR |
 334 #endif
 335       PARENB | PARODD);
 336
 337   if (parity != Parity::No) {
 338     fd_termios.c_cflag |= PARENB;
 339     if (parity == Parity::Odd || parity == Parity::Mark)
 340       fd_termios.c_cflag |= PARODD;
 341     if (parity == Parity::Mark || parity == Parity::Space) {
 342 #if defined(CMSPAR)
 343       fd_termios.c_cflag |= CMSPAR;
 344 #else
 345       return llvm::createStringError(
 346           llvm::inconvertibleErrorCode(),
 347           "space/mark parity is not supported by the platform");
 348 #endif
 349     }
 350   }
 351   return SetData(data.get());
 352 #else // !LLDB_ENABLE_TERMIOS
 353   return termiosMissingError();
 354 #endif // LLDB_ENABLE_TERMIOS
 355 }
 356
 357 llvm::Error Terminal::SetParityCheck(Terminal::ParityCheck parity_check) {
 358 #if LLDB_ENABLE_TERMIOS
 359   llvm::Expected<Data> data = GetData();
 360   if (!data)
 361     return data.takeError();
 362
 363   struct termios &fd_termios = data->m_termios;
 364   fd_termios.c_iflag &= ~(IGNPAR | PARMRK | INPCK);
 365
 366   if (parity_check != ParityCheck::No) {
 367     fd_termios.c_iflag |= INPCK;
 368     if (parity_check == ParityCheck::Ignore)
 369       fd_termios.c_iflag |= IGNPAR;
 370     else if (parity_check == ParityCheck::Mark)
 371       fd_termios.c_iflag |= PARMRK;
 372   }
 373   return SetData(data.get());
 374 #else // !LLDB_ENABLE_TERMIOS
 375   return termiosMissingError();
 376 #endif // LLDB_ENABLE_TERMIOS
 377 }
 378
 379 llvm::Error Terminal::SetHardwareFlowControl(bool enabled) {
 380 #if LLDB_ENABLE_TERMIOS
 381   llvm::Expected<Data> data = GetData();
 382   if (!data)
 383     return data.takeError();
 384
 385 #if defined(CRTSCTS)
 386   struct termios &fd_termios = data->m_termios;
 387   fd_termios.c_cflag &= ~CRTSCTS;
 388   if (enabled)
 389     fd_termios.c_cflag |= CRTSCTS;
 390   return SetData(data.get());
 391 #else  // !defined(CRTSCTS)
 392   if (enabled)
 393     return llvm::createStringError(
 394         llvm::inconvertibleErrorCode(),
 395         "hardware flow control is not supported by the platform");
 396   return llvm::Error::success();
 397 #endif // defined(CRTSCTS)
 398 #else // !LLDB_ENABLE_TERMIOS
 399   return termiosMissingError();
 400 #endif // LLDB_ENABLE_TERMIOS
 401 }
 402
 403 TerminalState::TerminalState(Terminal term, bool save_process_group)
 404     : m_tty(term) {
 405   Save(term, save_process_group);
 406 }
 407
 408 TerminalState::~TerminalState() { Restore(); }
 409
 410 void TerminalState::Clear() {
 411   m_tty.Clear();
 412   m_tflags = -1;
 413   m_data.reset();
 414   m_process_group = -1;
 415 }
 416
 417 bool TerminalState::Save(Terminal term, bool save_process_group) {
 418   Clear();
 419   m_tty = term;
 420   if (m_tty.IsATerminal()) {
 421 #if LLDB_ENABLE_POSIX
 422     int fd = m_tty.GetFileDescriptor();
 423     m_tflags = ::fcntl(fd, F_GETFL, 0);
 424 #if LLDB_ENABLE_TERMIOS
 425     std::unique_ptr<Terminal::Data> new_data{new Terminal::Data()};
 426     if (::tcgetattr(fd, &new_data->m_termios) == 0)
 427       m_data = std::move(new_data);
 428 #endif // LLDB_ENABLE_TERMIOS
 429     if (save_process_group)
 430       m_process_group = ::tcgetpgrp(fd);
 431 #endif // LLDB_ENABLE_POSIX
 432   }
 433   return IsValid();
 434 }
 435
 436 bool TerminalState::Restore() const {
 437 #if LLDB_ENABLE_POSIX
 438   if (IsValid()) {
 439     const int fd = m_tty.GetFileDescriptor();
 440     if (TFlagsIsValid())
 441       fcntl(fd, F_SETFL, m_tflags);
 442
 443 #if LLDB_ENABLE_TERMIOS
 444     if (TTYStateIsValid())
 445       tcsetattr(fd, TCSANOW, &m_data->m_termios);
 446 #endif // LLDB_ENABLE_TERMIOS
 447
 448     if (ProcessGroupIsValid()) {
 449       // Save the original signal handler.
 450       void (*saved_sigttou_callback)(int) = nullptr;
 451       saved_sigttou_callback = (void (*)(int))signal(SIGTTOU, SIG_IGN);
 452       // Set the process group
 453       tcsetpgrp(fd, m_process_group);
 454       // Restore the original signal handler.
 455       signal(SIGTTOU, saved_sigttou_callback);
 456     }
 457     return true;
 458   }
 459 #endif // LLDB_ENABLE_POSIX
 460   return false;
 461 }
 462
 463 bool TerminalState::IsValid() const {
 464   return m_tty.FileDescriptorIsValid() &&
 465          (TFlagsIsValid() || TTYStateIsValid() || ProcessGroupIsValid());
 466 }
 467
 468 bool TerminalState::TFlagsIsValid() const { return m_tflags != -1; }
 469
 470 bool TerminalState::TTYStateIsValid() const { return bool(m_data); }
 471
 472 bool TerminalState::ProcessGroupIsValid() const {
 473   return static_cast<int32_t>(m_process_group) != -1;
 474 }