1 //===-- Terminal.cpp --------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "lldb/Host/Terminal.h" 11 #include "lldb/Host/Config.h" 12 13 #include <fcntl.h> 14 #include <unistd.h> 15 #include <signal.h> 16 17 #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 18 #include <termios.h> 19 #endif 20 21 22 using namespace lldb_private; 23 24 bool 25 Terminal::IsATerminal () const 26 { 27 return m_fd >= 0 && ::isatty (m_fd); 28 } 29 30 31 bool 32 Terminal::SetEcho (bool enabled) 33 { 34 if (FileDescriptorIsValid()) 35 { 36 #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 37 if (IsATerminal ()) 38 { 39 struct termios fd_termios; 40 if (::tcgetattr(m_fd, &fd_termios) == 0) 41 { 42 bool set_corectly = false; 43 if (enabled) 44 { 45 if (fd_termios.c_lflag & ECHO) 46 set_corectly = true; 47 else 48 fd_termios.c_lflag |= ECHO; 49 } 50 else 51 { 52 if (fd_termios.c_lflag & ECHO) 53 fd_termios.c_lflag &= ~ECHO; 54 else 55 set_corectly = true; 56 } 57 58 if (set_corectly) 59 return true; 60 return ::tcsetattr (m_fd, TCSANOW, &fd_termios) == 0; 61 } 62 } 63 #endif // #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 64 } 65 return false; 66 } 67 68 bool 69 Terminal::SetCanonical (bool enabled) 70 { 71 if (FileDescriptorIsValid()) 72 { 73 #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 74 if (IsATerminal ()) 75 { 76 struct termios fd_termios; 77 if (::tcgetattr(m_fd, &fd_termios) == 0) 78 { 79 bool set_corectly = false; 80 if (enabled) 81 { 82 if (fd_termios.c_lflag & ICANON) 83 set_corectly = true; 84 else 85 fd_termios.c_lflag |= ICANON; 86 } 87 else 88 { 89 if (fd_termios.c_lflag & ICANON) 90 fd_termios.c_lflag &= ~ICANON; 91 else 92 set_corectly = true; 93 } 94 95 if (set_corectly) 96 return true; 97 return ::tcsetattr (m_fd, TCSANOW, &fd_termios) == 0; 98 } 99 } 100 #endif // #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 101 } 102 return false; 103 } 104 105 //---------------------------------------------------------------------- 106 // Default constructor 107 //---------------------------------------------------------------------- 108 TerminalState::TerminalState() : 109 m_tty(), 110 m_tflags(-1), 111 m_termios_ap(), 112 m_process_group(-1) 113 { 114 } 115 116 //---------------------------------------------------------------------- 117 // Destructor 118 //---------------------------------------------------------------------- 119 TerminalState::~TerminalState() 120 { 121 } 122 123 void 124 TerminalState::Clear () 125 { 126 m_tty.Clear(); 127 m_tflags = -1; 128 m_termios_ap.reset(); 129 m_process_group = -1; 130 } 131 132 //---------------------------------------------------------------------- 133 // Save the current state of the TTY for the file descriptor "fd" 134 // and if "save_process_group" is true, attempt to save the process 135 // group info for the TTY. 136 //---------------------------------------------------------------------- 137 bool 138 TerminalState::Save (int fd, bool save_process_group) 139 { 140 m_tty.SetFileDescriptor(fd); 141 if (m_tty.IsATerminal()) 142 { 143 m_tflags = ::fcntl (fd, F_GETFL, 0); 144 #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 145 if (m_termios_ap.get() == NULL) 146 m_termios_ap.reset (new struct termios); 147 int err = ::tcgetattr (fd, m_termios_ap.get()); 148 if (err != 0) 149 m_termios_ap.reset(); 150 #endif // #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 151 if (save_process_group) 152 m_process_group = ::tcgetpgrp (0); 153 else 154 m_process_group = -1; 155 } 156 else 157 { 158 m_tty.Clear(); 159 m_tflags = -1; 160 m_termios_ap.reset(); 161 m_process_group = -1; 162 } 163 return IsValid(); 164 } 165 166 //---------------------------------------------------------------------- 167 // Restore the state of the TTY using the cached values from a 168 // previous call to Save(). 169 //---------------------------------------------------------------------- 170 bool 171 TerminalState::Restore () const 172 { 173 if (IsValid()) 174 { 175 const int fd = m_tty.GetFileDescriptor(); 176 if (TFlagsIsValid()) 177 fcntl (fd, F_SETFL, m_tflags); 178 179 #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 180 if (TTYStateIsValid()) 181 tcsetattr (fd, TCSANOW, m_termios_ap.get()); 182 #endif // #ifdef LLDB_CONFIG_TERMIOS_SUPPORTED 183 184 if (ProcessGroupIsValid()) 185 { 186 // Save the original signal handler. 187 void (*saved_sigttou_callback) (int) = NULL; 188 saved_sigttou_callback = (void (*)(int)) signal (SIGTTOU, SIG_IGN); 189 // Set the process group 190 tcsetpgrp (fd, m_process_group); 191 // Restore the original signal handler. 192 signal (SIGTTOU, saved_sigttou_callback); 193 } 194 return true; 195 } 196 return false; 197 } 198 199 200 201 202 //---------------------------------------------------------------------- 203 // Returns true if this object has valid saved TTY state settings 204 // that can be used to restore a previous state. 205 //---------------------------------------------------------------------- 206 bool 207 TerminalState::IsValid() const 208 { 209 return m_tty.FileDescriptorIsValid () && (TFlagsIsValid() || TTYStateIsValid()); 210 } 211 212 //---------------------------------------------------------------------- 213 // Returns true if m_tflags is valid 214 //---------------------------------------------------------------------- 215 bool 216 TerminalState::TFlagsIsValid() const 217 { 218 return m_tflags != -1; 219 } 220 221 //---------------------------------------------------------------------- 222 // Returns true if m_ttystate is valid 223 //---------------------------------------------------------------------- 224 bool 225 TerminalState::TTYStateIsValid() const 226 { 227 return m_termios_ap.get() != 0; 228 } 229 230 //---------------------------------------------------------------------- 231 // Returns true if m_process_group is valid 232 //---------------------------------------------------------------------- 233 bool 234 TerminalState::ProcessGroupIsValid() const 235 { 236 return m_process_group != -1; 237 } 238 239 //------------------------------------------------------------------ 240 // Constructor 241 //------------------------------------------------------------------ 242 TerminalStateSwitcher::TerminalStateSwitcher () : 243 m_currentState(UINT32_MAX) 244 { 245 } 246 247 //------------------------------------------------------------------ 248 // Destructor 249 //------------------------------------------------------------------ 250 TerminalStateSwitcher::~TerminalStateSwitcher () 251 { 252 } 253 254 //------------------------------------------------------------------ 255 // Returns the number of states that this switcher contains 256 //------------------------------------------------------------------ 257 uint32_t 258 TerminalStateSwitcher::GetNumberOfStates() const 259 { 260 return sizeof(m_ttystates)/sizeof(TerminalState); 261 } 262 263 //------------------------------------------------------------------ 264 // Restore the state at index "idx". 265 // 266 // Returns true if the restore was successful, false otherwise. 267 //------------------------------------------------------------------ 268 bool 269 TerminalStateSwitcher::Restore (uint32_t idx) const 270 { 271 const uint32_t num_states = GetNumberOfStates(); 272 if (idx >= num_states) 273 return false; 274 275 // See if we already are in this state? 276 if (m_currentState < num_states && (idx == m_currentState) && m_ttystates[idx].IsValid()) 277 return true; 278 279 // Set the state to match the index passed in and only update the 280 // current state if there are no errors. 281 if (m_ttystates[idx].Restore()) 282 { 283 m_currentState = idx; 284 return true; 285 } 286 287 // We failed to set the state. The tty state was invalid or not 288 // initialized. 289 return false; 290 } 291 292 //------------------------------------------------------------------ 293 // Save the state at index "idx" for file descriptor "fd" and 294 // save the process group if requested. 295 // 296 // Returns true if the restore was successful, false otherwise. 297 //------------------------------------------------------------------ 298 bool 299 TerminalStateSwitcher::Save (uint32_t idx, int fd, bool save_process_group) 300 { 301 const uint32_t num_states = GetNumberOfStates(); 302 if (idx < num_states) 303 return m_ttystates[idx].Save(fd, save_process_group); 304 return false; 305 } 306 307 308
