0
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1 /* Handling asynchronous signals.
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2 Copyright (C) 1992, 1993, 1994 Free Software Foundation, Inc.
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3 Copyright (C) 1995, 1996 Ben Wing.
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4
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5 This file is part of XEmacs.
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6
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7 XEmacs is free software; you can redistribute it and/or modify it
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8 under the terms of the GNU General Public License as published by the
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9 Free Software Foundation; either version 2, or (at your option) any
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10 later version.
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11
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12 XEmacs is distributed in the hope that it will be useful, but WITHOUT
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13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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15 for more details.
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16
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17 You should have received a copy of the GNU General Public License
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18 along with XEmacs; see the file COPYING. If not, write to
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19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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20 Boston, MA 02111-1307, USA. */
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21
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22 /* Synched up with: Not synched with FSF. Split out of keyboard.c. */
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23
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24 #include <config.h>
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25 #include "lisp.h"
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26
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27 #include "console.h"
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28 #include "events.h" /* for signal_fake_event() */
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29 #include "frame.h"
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30 #include "sysdep.h"
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31 #include "syssignal.h"
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32 #include "systime.h"
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33
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272
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34 #ifdef HAVE_UNISTD_H
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35 #include <unistd.h>
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36 #endif
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0
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37 #include <errno.h>
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38
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39 /* Set to 1 when a quit-check signal (either a SIGIO interrupt or
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40 the asynch. timeout for poll-for-quit) occurs. The QUITP
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41 macro may look at this. */
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42 volatile int quit_check_signal_happened;
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43
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44 /* Count of the number of times a quit-check signal has occurred.
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45 Some stuff in event-Xt.c looks at this. */
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46 volatile int quit_check_signal_tick_count;
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47
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48 /* Set to 1 when a SIGINT (or SIGQUIT) interrupt is processed.
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49 maybe_read_quit_event() looks at this. */
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50 volatile int sigint_happened;
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51
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52 /* Set to 1 when an asynch. timeout signal occurs. */
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53 static volatile int alarm_happened;
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54
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55 /* This is used to synchronize setting the waiting_for_user_input_p
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56 flag. */
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57 static volatile int alarm_happened_while_emacs_was_blocking;
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58
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59 /* See check_quit() for when this is set. */
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60 int dont_check_for_quit;
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61
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62 #if !defined (SIGIO) && !defined (DONT_POLL_FOR_QUIT)
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63 int poll_for_quit_id;
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64 #endif
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65
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276
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66 #if defined(HAVE_UNIX_PROCESSES) && !defined(SIGCHLD)
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67 int poll_for_sigchld_id;
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68 #endif
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69
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70 /* This variable is used to communicate to a lisp
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71 process-filter/sentinel/asynchronous callback (via the function
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72 Fwaiting_for_user_input_p below) whether XEmacs was waiting for
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73 user-input when that process-filter was called. */
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74 static int waiting_for_user_input_p;
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75
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76 static int interrupts_slowed_down;
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77
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104
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78 #define SLOWED_DOWN_INTERRUPTS_SECS 15
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79 #define NORMAL_QUIT_CHECK_TIMEOUT_MSECS 250
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80 #define NORMAL_SIGCHLD_CHECK_TIMEOUT_MSECS 250
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81
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82 /* Used so that signals can break out of system calls that aren't
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83 naturally interruptible. */
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84
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85 JMP_BUF break_system_call_jump;
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16
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86 volatile int can_break_system_calls;
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87
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88
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89 /**********************************************************************/
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90 /* Asynchronous timeout functions */
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91 /**********************************************************************/
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92
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93 /* The pending timers are stored in an ordered list, where the first timer
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94 on the list is the first one to fire. Times recorded here are
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95 absolute. */
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96 static struct low_level_timeout *async_timer_queue;
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97
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98 /* Nonzero means async timers are temporarily suppressed. */
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99 static int async_timer_suppress_count;
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100
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101 static void
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102 set_one_shot_timer (EMACS_TIME interval)
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103 {
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104 #ifdef HAVE_SETITIMER
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105 struct itimerval it;
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106 it.it_value = interval;
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107 EMACS_SET_SECS_USECS (it.it_interval, 0, 0);
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108 setitimer (ITIMER_REAL, &it, 0);
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109 #else
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110 int secs;
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111 EMACS_TIME_TO_INT (interval, secs);
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112 alarm (secs);
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113 #endif
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114 }
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115
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116 static void
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117 reset_interval_timer (void)
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118 {
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119 EMACS_TIME interval;
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120
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121 /* Get the interval to set. If an interval is available,
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122 make sure it's not zero (this is a valid return, but it will
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123 cause the timer to get disabled, so convert it to a very short
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124 time). */
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125 if (get_low_level_timeout_interval (async_timer_queue, &interval))
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126 {
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127 if (EMACS_SECS (interval) == 0 && EMACS_USECS (interval) == 0)
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128 EMACS_SET_USECS (interval, 1);
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129 }
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130 else
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131 /* A time of 0 means "disable". */
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132 EMACS_SET_SECS_USECS (interval, 0, 0);
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133
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134 set_one_shot_timer (interval);
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135 }
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136
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137 int
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138 event_stream_add_async_timeout (EMACS_TIME thyme)
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139 {
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140 int id = add_low_level_timeout (&async_timer_queue, thyme);
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141
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142 /* If this timeout is at the head of the queue, then we need to
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143 set the timer right now for this timeout. Otherwise, things
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144 are fine as-is; after the timers ahead of us are signalled,
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145 the timer will be set for us. */
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146
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147 if (async_timer_queue->id == id)
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148 reset_interval_timer ();
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149
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150 return id;
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151 }
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152
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153 void
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154 event_stream_remove_async_timeout (int id)
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155 {
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156 int first = (async_timer_queue && async_timer_queue->id == id);
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157 remove_low_level_timeout (&async_timer_queue, id);
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158
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159 /* If we removed the timeout from the head of the queue, then
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160 we need to reset the interval timer right now. */
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161 if (first)
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162 reset_interval_timer ();
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163 }
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164
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165 /* Handle an alarm once each second and read pending input
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166 so as to handle a C-g if it comes in. */
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167
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168 static SIGTYPE
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169 alarm_signal (int signo)
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170 {
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171 if (interrupts_slowed_down)
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172 {
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173 something_happened = 1; /* tell QUIT to wake up */
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174 /* we are in "slowed-down interrupts" mode; the only alarm
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175 happening here is the slowed-down quit-check alarm, so
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176 we set this flag.
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177
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178 Do NOT set alarm_happened, because we don't want anyone
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179 looking at the timeout queue. We didn't set it and
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180 it needs to stay the way it is. */
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181 quit_check_signal_happened = 1;
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182
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278
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183 #ifdef WINDOWSNT
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223
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184 can_break_system_calls = 0;
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185 #else
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0
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186 /* can_break_system_calls is set when we want to break out of
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187 non-interruptible system calls. */
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188 if (can_break_system_calls)
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189 {
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190 /* reset the flag for safety and such. Do this *before*
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191 unblocking or reestablishing the signal to avoid potential
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192 race conditions. */
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193 can_break_system_calls = 0;
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194 EMACS_UNBLOCK_SIGNAL (signo);
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195 EMACS_REESTABLISH_SIGNAL (signo, alarm_signal);
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196 LONGJMP (break_system_call_jump, 0);
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197 }
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223
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198 #endif
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0
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199
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200 EMACS_REESTABLISH_SIGNAL (signo, alarm_signal);
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201 SIGRETURN;
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202 }
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203
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204 something_happened = 1; /* tell QUIT to wake up */
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205 alarm_happened = 1;
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206 if (emacs_is_blocking)
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207 alarm_happened_while_emacs_was_blocking = 1;
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208 /* #### This is for QUITP. When it is run, it may not be the
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209 place to do arbitrary stuff like run asynch. handlers, but
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210 it needs to know whether the poll-for-quit asynch. timeout
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211 went off. Rather than put the code in to compute this
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212 specially, we just set this flag. Should fix this. */
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213 quit_check_signal_happened = 1;
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223
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214
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215 #ifdef HAVE_UNIXOID_EVENT_LOOP
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216 signal_fake_event ();
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223
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217 #endif
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218
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219 EMACS_REESTABLISH_SIGNAL (signo, alarm_signal);
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220 SIGRETURN;
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221 }
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222
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223 static void
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224 init_async_timeouts (void)
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225 {
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226 signal (SIGALRM, alarm_signal);
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227 async_timer_suppress_count = 0;
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228 }
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229
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230 /* Turn off async timeouts. */
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231
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232 static void
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233 stop_async_timeouts (void)
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234 {
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235 if (async_timer_suppress_count == 0)
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236 {
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237 /* If timer was on, turn it off. */
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238 EMACS_TIME thyme;
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239 EMACS_SET_SECS_USECS (thyme, 0, 0);
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240 set_one_shot_timer (thyme);
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241 }
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242 async_timer_suppress_count++;
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243 }
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244
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245 /* Turn on async timeouts again. */
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246
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247 static void
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248 start_async_timeouts (void)
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249 {
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250 assert (async_timer_suppress_count > 0);
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251 async_timer_suppress_count--;
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252 if (async_timer_suppress_count == 0)
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253 {
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254 /* Some callers turn off async timeouts and then use the alarm
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255 for their own purposes; so reinitialize everything. */
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256 signal (SIGALRM, alarm_signal);
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257 reset_interval_timer ();
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258 }
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259 }
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260
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261 /* Some functions don't like being interrupted with SIGALRM or SIGIO.
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262 Previously we were calling stop_interrupts() / start_interrupts(),
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263 but then if the program hangs in one of those functions, e.g.
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264 waiting for a connect(), we're really screwed. So instead we
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265 just "slow them down". We do this by disabling all interrupts
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266 and then installing a timer of length fairly large, like 5 or
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267 10 secs. That way, any "legitimate" connections (which should
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268 take a fairly short amount of time) go through OK, but we can
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269 interrupt bogus ones. */
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270
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271 void
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272 slow_down_interrupts (void)
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273 {
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274 EMACS_TIME thyme;
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275
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276 /* We have to set the flag *before* setting the slowed-down timer,
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277 to avoid a race condition -- if the signal occurs between the
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278 call to set_one_shot_timer() and the setting of this flag,
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279 alarm_happened will get set, which will be a Bad Thing if
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280 there were no timeouts on the queue. */
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281 interrupts_slowed_down++;
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282 if (interrupts_slowed_down == 1)
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283 {
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284 stop_interrupts ();
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285 EMACS_SET_SECS_USECS (thyme, SLOWED_DOWN_INTERRUPTS_SECS, 0);
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286 set_one_shot_timer (thyme);
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287 }
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288 }
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289
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290 void
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291 speed_up_interrupts (void)
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292 {
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293 if (interrupts_slowed_down > 0)
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294 {
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295 start_interrupts ();
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296 /* Change this flag AFTER fiddling with interrupts, for the same
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297 race-condition reasons as above. */
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298 interrupts_slowed_down--;
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299 }
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300 }
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301
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302 static void
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303 handle_alarm_going_off (void)
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304 {
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305 int interval_id;
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306
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307 /* If asynch. timeouts are blocked, then don't do anything now,
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308 but make this function get called again next QUIT.
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309
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310 #### This is a bit inefficient because there will be function call
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311 overhead each time QUIT occurs. */
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272
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312
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0
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313 if (!NILP (Vinhibit_quit))
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314 {
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315 something_happened = 1;
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316 alarm_happened = 1;
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317 return;
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318 }
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319
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320 interval_id = pop_low_level_timeout (&async_timer_queue, 0);
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321
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322 reset_interval_timer ();
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323 if (alarm_happened_while_emacs_was_blocking)
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324 {
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325 alarm_happened_while_emacs_was_blocking = 0;
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326 waiting_for_user_input_p = 1;
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327 }
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328 event_stream_deal_with_async_timeout (interval_id);
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329 waiting_for_user_input_p = 0;
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330 }
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331
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332 #ifdef HAVE_SETITIMER
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333 unsigned int
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334 alarm (unsigned int howlong)
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335 {
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336 struct itimerval old_it, new_it;
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337
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338 /* If alarm() gets called when polling isn't disabled, it can mess
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339 up the periodic timer. */
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340 assert (async_timer_suppress_count > 0);
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341
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342 new_it.it_value.tv_sec = howlong;
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343 new_it.it_value.tv_usec = 0;
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344 new_it.it_interval.tv_sec = 0;
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345 new_it.it_interval.tv_usec = 0;
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346 setitimer (ITIMER_REAL, &new_it, &old_it);
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347
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348 /* Never return zero if there was a timer outstanding. */
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349 return old_it.it_value.tv_sec + (old_it.it_value.tv_usec > 0 ? 1 : 0);
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350 }
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351 #endif
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352
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20
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353 DEFUN ("waiting-for-user-input-p", Fwaiting_for_user_input_p, 0, 0, 0, /*
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0
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354 Return non-nil if XEmacs is waiting for input from the user.
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355 This is intended for use by asynchronous timeout callbacks and by
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356 asynchronous process output filters and sentinels (not yet implemented
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357 in XEmacs). It will always be nil if XEmacs is not inside of
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358 an asynchronout timeout or process callback.
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20
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359 */
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360 ())
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0
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361 {
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272
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362 return waiting_for_user_input_p ? Qt : Qnil;
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0
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363 }
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364
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365
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366 /**********************************************************************/
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367 /* Control-G checking */
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368 /**********************************************************************/
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369
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370 /* Set this for debugging, to have a way to get out */
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371 int stop_character; /* #### not currently implemented */
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372
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373 /* This routine is called in response to a SIGINT or SIGQUIT.
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374 On TTY's, one of these two signals will get generated in response
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375 to C-g. (When running under X, C-g is handled using the SIGIO
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376 handler, which sets a flag telling the QUIT macro to scan the
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377 unread events for a ^G.)
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378
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379 Otherwise it sets the Lisp variable quit-flag not-nil.
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380 This causes eval to throw, when it gets a chance.
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381 If quit-flag is already non-nil, it stops the job right away. */
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382
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383 static SIGTYPE
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384 interrupt_signal (int sig)
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385 {
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116
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386 /* This function can call lisp */
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387 /* #### we should NOT be calling lisp from a signal handler, boys
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388 and girls */
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0
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389 /* Must preserve main program's value of errno. */
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390 int old_errno = errno;
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391
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392 EMACS_REESTABLISH_SIGNAL (sig, interrupt_signal);
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393
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394 /* with the macroized error-checking stuff, the garbage below
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395 may mess things up because XCONSOLE() and such can use and
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396 change global vars. */
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397 #if ! (defined (ERROR_CHECK_TYPECHECK) && defined (MACROIZE_ERROR_CHECKING))
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398 if (sigint_happened && CONSOLEP (Vcontrolling_terminal) &&
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399 CONSOLE_LIVE_P (XCONSOLE (Vcontrolling_terminal)) &&
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400 !emacs_is_blocking)
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401 {
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402 char c;
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403 fflush (stdout);
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404 reset_initial_console ();
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405 EMACS_UNBLOCK_SIGNAL (sig);
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406 #ifdef SIGTSTP /* Support possible in later USG versions */
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407 /*
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408 * On systems which can suspend the current process and return to the original
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409 * shell, this command causes the user to end up back at the shell.
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410 * The "Auto-save" and "Abort" questions are not asked until
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411 * the user elects to return to emacs, at which point he can save the current
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412 * job and either dump core or continue.
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413 */
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414 sys_suspend ();
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415 #else
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416 /* Perhaps should really fork an inferior shell?
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417 But that would not provide any way to get back
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418 to the original shell, ever. */
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419 stdout_out ("No support for stopping a process on this operating system;\n");
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420 stdout_out ("you can continue or abort.\n");
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421 #endif /* not SIGTSTP */
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422 stdout_out ("Auto-save? (y or n) ");
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423 fflush (stdout);
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424 if (((c = getc (stdin)) & ~040) == 'Y')
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425 Fdo_auto_save (Qnil, Qnil);
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426 while (c != '\n')
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427 c = getc (stdin);
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428 stdout_out ("Abort (and dump core)? (y or n) ");
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429 fflush (stdout);
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430 if (((c = getc (stdin)) & ~040) == 'Y')
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431 abort ();
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432 while (c != '\n')
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433 c = getc (stdin);
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434 stdout_out ("Continuing...\n");
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435 fflush (stdout);
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436 reinit_initial_console ();
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437 MARK_FRAME_CHANGED (XFRAME (DEVICE_SELECTED_FRAME
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438 (XDEVICE (CONSOLE_SELECTED_DEVICE
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439 (XCONSOLE
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440 (Vcontrolling_terminal))))));
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441 }
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442 else
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443 #endif /* ! (defined (ERROR_CHECKING) && defined (MACROIZE_ERROR_CHECKING)) */
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444 {
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445 /* Else request quit when it's safe */
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446 Vquit_flag = Qt;
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447 sigint_happened = 1;
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223
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448 #ifdef HAVE_UNIXOID_EVENT_LOOP
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0
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449 signal_fake_event ();
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223
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450 #endif
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0
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451 }
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452 errno = old_errno;
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453 SIGRETURN;
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454 }
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455
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456 static Lisp_Object
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457 restore_dont_check_for_quit (Lisp_Object val)
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458 {
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459 dont_check_for_quit = XINT (val);
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460 return Qnil;
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461 }
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462
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463 void
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464 begin_dont_check_for_quit (void)
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465 {
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466 specbind (Qinhibit_quit, Qt);
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467 record_unwind_protect (restore_dont_check_for_quit,
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468 make_int (dont_check_for_quit));
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469 dont_check_for_quit = 1;
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470 }
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471
|
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472 /* The effect of this function is to set Vquit_flag if the user pressed
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473 ^G and discard the ^G, so as to not notice the same ^G again. */
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272
|
474 int
|
0
|
475 check_quit (void)
|
|
476 {
|
|
477 /* dont_check_for_quit is set in two circumstances:
|
|
478
|
|
479 (1) when we are in the process of changing the window
|
|
480 configuration. The frame might be in an inconsistent state,
|
|
481 which will cause assertion failures if we check for QUIT.
|
|
482
|
|
483 (2) when we are reading events, and want to read the C-g
|
|
484 as an event. The normal check for quit will discard the C-g,
|
|
485 which would be bad.
|
|
486
|
|
487 #### C-g is still often read as quit, e.g. if you type C-x C-g
|
|
488 (the C-g happens during the sit-for in maybe_echo_keys(); even
|
|
489 if we attempt to inhibit quit here, there is still a check
|
|
490 later on for QUIT. To fix this properly requires a fairly
|
|
491 substantial overhaul of the quit-checking code, which is
|
|
492 probably not worth it.)
|
|
493
|
|
494 We should *not* conditionalize on Vinhibit_quit, or
|
|
495 critical-quit (Control-Shift-G) won't work right. */
|
|
496
|
|
497 if (dont_check_for_quit)
|
|
498 return 0;
|
|
499
|
|
500 if (quit_check_signal_happened)
|
|
501 {
|
|
502 quit_check_signal_happened = 0;
|
|
503 event_stream_quit_p ();
|
|
504 return 1;
|
|
505 }
|
|
506 else
|
|
507 return 0;
|
|
508 }
|
|
509
|
|
510 int
|
|
511 check_what_happened (void) /* called from QUIT when
|
|
512 something_happened gets set */
|
|
513 {
|
|
514 something_happened = 0;
|
|
515 if (alarm_happened)
|
|
516 {
|
|
517 alarm_happened = 0;
|
|
518 handle_alarm_going_off ();
|
|
519 }
|
|
520 return check_quit ();
|
|
521 }
|
|
522
|
272
|
523
|
0
|
524
|
|
525 void
|
|
526 init_poll_for_quit (void)
|
|
527 {
|
|
528 #if !defined (SIGIO) && !defined (DONT_POLL_FOR_QUIT)
|
|
529 /* Check for C-g every 1/4 of a second.
|
|
530
|
|
531 #### This is just a guess. Some investigation will have to be
|
|
532 done to see what the best value is. The best value is the
|
|
533 smallest possible value that doesn't cause a significant amount
|
|
534 of running time to be spent in C-g checking. */
|
|
535 if (!poll_for_quit_id)
|
|
536 poll_for_quit_id =
|
|
537 event_stream_generate_wakeup (NORMAL_QUIT_CHECK_TIMEOUT_MSECS,
|
|
538 NORMAL_QUIT_CHECK_TIMEOUT_MSECS,
|
|
539 Qnil, Qnil, 1);
|
|
540 #endif /* not SIGIO and not DONT_POLL_FOR_QUIT */
|
|
541 }
|
|
542
|
|
543 void
|
|
544 reset_poll_for_quit (void)
|
|
545 {
|
|
546 #if !defined (SIGIO) && !defined (DONT_POLL_FOR_QUIT)
|
|
547 if (poll_for_quit_id)
|
|
548 {
|
|
549 event_stream_disable_wakeup (poll_for_quit_id, 1);
|
|
550 poll_for_quit_id = 0;
|
|
551 }
|
|
552 #endif /* not SIGIO and not DONT_POLL_FOR_QUIT */
|
|
553 }
|
|
554
|
276
|
555 #if defined(HAVE_UNIX_PROCESSES) && !defined(SIGCHLD)
|
0
|
556
|
|
557 static void
|
|
558 init_poll_for_sigchld (void)
|
|
559 {
|
|
560 /* Check for terminated processes every 1/4 of a second.
|
|
561
|
|
562 #### This is just a guess. Some investigation will have to be
|
|
563 done to see what the best value is. The best value is the
|
|
564 smallest possible value that doesn't cause a significant amount
|
|
565 of running time to be spent in process-termination checking.
|
|
566 */
|
|
567 poll_for_sigchld_id =
|
|
568 event_stream_generate_wakeup (NORMAL_SIGCHLD_CHECK_TIMEOUT_MSECS,
|
|
569 NORMAL_SIGCHLD_CHECK_TIMEOUT_MSECS,
|
|
570 Qnil, Qnil, 1);
|
|
571 }
|
|
572
|
|
573 #endif /* not SIGCHLD */
|
|
574
|
|
575 #ifdef SIGIO
|
|
576
|
|
577 static void
|
|
578 input_available_signal (int signo)
|
|
579 {
|
|
580 something_happened = 1; /* tell QUIT to wake up */
|
|
581 quit_check_signal_happened = 1;
|
|
582 quit_check_signal_tick_count++;
|
|
583 EMACS_REESTABLISH_SIGNAL (signo, input_available_signal);
|
|
584 SIGRETURN;
|
|
585 }
|
|
586
|
|
587 #endif /* SIGIO */
|
|
588
|
|
589
|
|
590 /**********************************************************************/
|
|
591 /* Enabling/disabling signals */
|
|
592 /**********************************************************************/
|
|
593
|
|
594 static int interrupts_initted;
|
|
595
|
|
596 void
|
|
597 stop_interrupts (void)
|
|
598 {
|
|
599 if (!interrupts_initted)
|
|
600 return;
|
251
|
601 #if defined(SIGIO) && !defined(BROKEN_SIGIO)
|
0
|
602 unrequest_sigio ();
|
|
603 #endif
|
|
604 stop_async_timeouts ();
|
|
605 }
|
|
606
|
|
607 void
|
|
608 start_interrupts (void)
|
|
609 {
|
|
610 if (!interrupts_initted)
|
|
611 return;
|
251
|
612 #if defined(SIGIO) && !defined(BROKEN_SIGIO)
|
0
|
613 request_sigio ();
|
|
614 #endif
|
|
615 start_async_timeouts ();
|
|
616 }
|
|
617
|
|
618 /* Cheesy but workable implementation of sleep() that doesn't
|
16
|
619 interfere with our periodic timers. */
|
0
|
620
|
|
621 void
|
|
622 emacs_sleep (int secs)
|
|
623 {
|
|
624 stop_interrupts ();
|
|
625 sleep (secs);
|
|
626 start_interrupts ();
|
|
627 }
|
|
628
|
|
629
|
|
630 /************************************************************************/
|
|
631 /* initialization */
|
|
632 /************************************************************************/
|
|
633
|
280
|
634 /* If we've been nohup'ed, keep it that way.
|
|
635 This allows `nohup xemacs &' to work.
|
|
636 More generally, if a normally fatal signal has been redirected
|
|
637 to SIG_IGN by our invocation environment, trust the environment.
|
|
638 This keeps xemacs from being killed by a SIGQUIT intended for a
|
|
639 different process after having been backgrounded under a
|
|
640 non-job-control shell! */
|
|
641 static void
|
|
642 handle_signal_if_fatal (int signo)
|
|
643 {
|
|
644 if (signal (signo, fatal_error_signal) == SIG_IGN)
|
|
645 signal (signo, SIG_IGN);
|
|
646 }
|
|
647
|
0
|
648 void
|
|
649 init_signals_very_early (void)
|
|
650 {
|
280
|
651 /* Catch all signals that would kill us.
|
|
652 Don't catch these signals in batch mode if not initialized.
|
|
653 On some machines, this sets static data that would make
|
|
654 signal fail to work right when the dumped Emacs is run. */
|
|
655 if (noninteractive && !initialized)
|
|
656 return;
|
|
657
|
|
658 handle_signal_if_fatal (SIGILL); /* ANSI */
|
|
659 handle_signal_if_fatal (SIGABRT); /* ANSI */
|
|
660 handle_signal_if_fatal (SIGFPE); /* ANSI */
|
|
661 handle_signal_if_fatal (SIGSEGV); /* ANSI */
|
|
662 handle_signal_if_fatal (SIGTERM); /* ANSI */
|
|
663
|
|
664
|
276
|
665 #ifdef SIGHUP
|
280
|
666 handle_signal_if_fatal (SIGHUP); /* POSIX */
|
276
|
667 #endif
|
|
668 #ifdef SIGQUIT
|
280
|
669 handle_signal_if_fatal (SIGQUIT); /* POSIX */
|
276
|
670 #endif
|
274
|
671 #ifdef SIGTRAP
|
280
|
672 handle_signal_if_fatal (SIGTRAP); /* POSIX */
|
|
673 #endif
|
|
674 #ifdef SIGUSR1
|
|
675 handle_signal_if_fatal (SIGUSR1); /* POSIX */
|
|
676 #endif
|
|
677 #ifdef SIGUSR2
|
|
678 handle_signal_if_fatal (SIGUSR2); /* POSIX */
|
|
679 #endif
|
|
680 #ifdef SIGPIPE
|
|
681 handle_signal_if_fatal (SIGPIPE); /* POSIX */
|
|
682 #endif
|
|
683 #ifdef SIGALRM
|
|
684 /* This will get reset later, once we're
|
|
685 capable of handling it properly. */
|
|
686 handle_signal_if_fatal (SIGALRM); /* POSIX */
|
|
687 #endif
|
|
688
|
|
689
|
|
690 #ifdef SIGBUS
|
|
691 handle_signal_if_fatal (SIGBUS); /* XPG5 */
|
274
|
692 #endif
|
280
|
693 #ifdef SIGSYS
|
|
694 handle_signal_if_fatal (SIGSYS); /* XPG5 */
|
|
695 #endif
|
|
696 #ifdef SIGXCPU
|
|
697 handle_signal_if_fatal (SIGXCPU); /* XPG5 */
|
|
698 #endif
|
|
699 #ifdef SIGXFSZ
|
|
700 handle_signal_if_fatal (SIGXFSZ); /* XPG5 */
|
0
|
701 #endif
|
280
|
702 #ifdef SIGVTALRM
|
|
703 handle_signal_if_fatal (SIGVTALRM); /* XPG5 */
|
|
704 #endif
|
|
705 #ifdef SIGPROF
|
|
706 /* Messes up the REAL profiler */
|
|
707 /* handle_signal_if_fatal (SIGPROF); */ /* XPG5 */
|
|
708 #endif
|
|
709
|
|
710
|
0
|
711 #ifdef SIGHWE
|
280
|
712 handle_signal_if_fatal (SIGHWE);
|
0
|
713 #endif
|
|
714 #ifdef SIGPRE
|
280
|
715 handle_signal_if_fatal (SIGPRE);
|
0
|
716 #endif
|
|
717 #ifdef SIGORE
|
280
|
718 handle_signal_if_fatal (SIGORE);
|
0
|
719 #endif
|
|
720 #ifdef SIGUME
|
280
|
721 handle_signal_if_fatal (SIGUME);
|
0
|
722 #endif
|
|
723 #ifdef SIGDLK
|
280
|
724 handle_signal_if_fatal (SIGDLK);
|
0
|
725 #endif
|
|
726 #ifdef SIGCPULIM
|
280
|
727 handle_signal_if_fatal (SIGCPULIM);
|
0
|
728 #endif
|
|
729 #ifdef SIGIOT
|
280
|
730 handle_signal_if_fatal (SIGIOT);
|
0
|
731 #endif
|
|
732 #ifdef SIGEMT
|
280
|
733 handle_signal_if_fatal (SIGEMT);
|
274
|
734 #endif
|
0
|
735 #ifdef SIGLOST
|
280
|
736 handle_signal_if_fatal (SIGLOST);
|
0
|
737 #endif
|
|
738 #ifdef SIGSTKFLT /* coprocessor stack fault under Linux */
|
280
|
739 handle_signal_if_fatal (SIGSTKFLT);
|
0
|
740 #endif
|
|
741 #ifdef SIGUNUSED /* exists under Linux, and will kill process! */
|
280
|
742 handle_signal_if_fatal (SIGUNUSED);
|
0
|
743 #endif
|
|
744
|
|
745 #ifdef AIX
|
|
746 /* 20 is SIGCHLD, 21 is SIGTTIN, 22 is SIGTTOU. */
|
|
747 #ifndef _I386
|
280
|
748 handle_signal_if_fatal (SIGIOINT);
|
0
|
749 #endif
|
280
|
750 handle_signal_if_fatal (SIGGRANT);
|
|
751 handle_signal_if_fatal (SIGRETRACT);
|
|
752 handle_signal_if_fatal (SIGSOUND);
|
|
753 handle_signal_if_fatal (SIGMSG);
|
0
|
754 #endif /* AIX */
|
280
|
755
|
|
756 #ifdef SIGDANGER
|
|
757 /* This just means available memory is getting low. */
|
|
758 signal (SIGDANGER, memory_warning_signal);
|
|
759 #endif
|
0
|
760 }
|
|
761
|
|
762 void
|
|
763 syms_of_signal (void)
|
|
764 {
|
20
|
765 DEFSUBR (Fwaiting_for_user_input_p);
|
0
|
766 }
|
|
767
|
|
768 void
|
|
769 init_interrupts_late (void)
|
|
770 {
|
|
771 if (!noninteractive)
|
|
772 {
|
|
773 signal (SIGINT, interrupt_signal);
|
|
774 #ifdef HAVE_TERMIO
|
|
775 /* On systems with TERMIO, C-g is set up for both SIGINT and SIGQUIT
|
|
776 and we can't tell which one it will give us. */
|
|
777 signal (SIGQUIT, interrupt_signal);
|
|
778 #endif /* HAVE_TERMIO */
|
|
779 init_async_timeouts ();
|
|
780 #ifdef SIGIO
|
|
781 signal (SIGIO, input_available_signal);
|
280
|
782 # ifdef SIGPOLL /* XPG5 */
|
0
|
783 /* Some systems (e.g. Motorola SVR4) losingly have different
|
|
784 values for SIGIO and SIGPOLL, and send SIGPOLL instead of
|
|
785 SIGIO. On those same systems, an uncaught SIGPOLL kills the
|
|
786 process. */
|
|
787 signal (SIGPOLL, input_available_signal);
|
|
788 # endif
|
|
789 #elif !defined (DONT_POLL_FOR_QUIT)
|
|
790 init_poll_for_quit ();
|
|
791 #endif
|
|
792 }
|
|
793
|
276
|
794 #if defined(HAVE_UNIX_PROCESSES) && !defined(SIGCHLD)
|
0
|
795 init_poll_for_sigchld ();
|
|
796 #endif
|
|
797
|
|
798 EMACS_UNBLOCK_ALL_SIGNALS ();
|
|
799
|
|
800 interrupts_initted = 1;
|
|
801 }
|
|
802
|