1 //===-- TTYState.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 // Created by Greg Clayton on 3/26/07.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "TTYState.h"
15 #include <fcntl.h>
16 #include <unistd.h>
17 #include <sys/signal.h>
18
TTYState()19 TTYState::TTYState() :
20 m_fd(-1),
21 m_tflags(-1),
22 m_ttystateErr(-1),
23 m_processGroup(-1)
24 {
25 }
26
~TTYState()27 TTYState::~TTYState()
28 {
29 }
30
31 bool
GetTTYState(int fd,bool saveProcessGroup)32 TTYState::GetTTYState (int fd, bool saveProcessGroup)
33 {
34 if (fd >= 0 && ::isatty (fd))
35 {
36 m_fd = fd;
37 m_tflags = fcntl (fd, F_GETFL, 0);
38 m_ttystateErr = tcgetattr (fd, &m_ttystate);
39 if (saveProcessGroup)
40 m_processGroup = tcgetpgrp (0);
41 else
42 m_processGroup = -1;
43 }
44 else
45 {
46 m_fd = -1;
47 m_tflags = -1;
48 m_ttystateErr = -1;
49 m_processGroup = -1;
50 }
51 return m_ttystateErr == 0;
52 }
53
54 bool
SetTTYState() const55 TTYState::SetTTYState () const
56 {
57 int result = 0;
58 if (IsValid())
59 {
60 if (TFlagsValid())
61 result = fcntl (m_fd, F_SETFL, m_tflags);
62
63 if (TTYStateValid())
64 result = tcsetattr (m_fd, TCSANOW, &m_ttystate);
65
66 if (ProcessGroupValid())
67 {
68 // Save the original signal handler.
69 void (*saved_sigttou_callback) (int) = NULL;
70 saved_sigttou_callback = (void (*)(int)) signal (SIGTTOU, SIG_IGN);
71 // Set the process group
72 result = tcsetpgrp (m_fd, m_processGroup);
73 // Restore the original signal handler.
74 signal (SIGTTOU, saved_sigttou_callback);
75 }
76 return true;
77 }
78 return false;
79 }
80
81
82
TTYStateSwitcher()83 TTYStateSwitcher::TTYStateSwitcher() :
84 m_currentState(~0)
85 {
86 }
87
~TTYStateSwitcher()88 TTYStateSwitcher::~TTYStateSwitcher()
89 {
90 }
91
92 bool
GetState(uint32_t idx,int fd,bool saveProcessGroup)93 TTYStateSwitcher::GetState(uint32_t idx, int fd, bool saveProcessGroup)
94 {
95 if (ValidStateIndex(idx))
96 return m_ttystates[idx].GetTTYState(fd, saveProcessGroup);
97 return false;
98 }
99
100 bool
SetState(uint32_t idx) const101 TTYStateSwitcher::SetState(uint32_t idx) const
102 {
103 if (!ValidStateIndex(idx))
104 return false;
105
106 // See if we already are in this state?
107 if (ValidStateIndex(m_currentState) && (idx == m_currentState) && m_ttystates[idx].IsValid())
108 return true;
109
110 // Set the state to match the index passed in and only update the
111 // current state if there are no errors.
112 if (m_ttystates[idx].SetTTYState())
113 {
114 m_currentState = idx;
115 return true;
116 }
117
118 // We failed to set the state. The tty state was invalid or not
119 // initialized.
120 return false;
121 }
122
123