1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1996 - 2001, 2009 Brian Somers <brian@Awfulhak.org> 5 * based on work by Toshiharu OHNO <tony-o@iij.ad.jp> 6 * Internet Initiative Japan, Inc (IIJ) 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <errno.h> 32 #include <signal.h> 33 #include <stdarg.h> 34 #include <stdio.h> 35 #include <string.h> 36 #include <sys/time.h> 37 #include <termios.h> 38 39 #include "log.h" 40 #include "sig.h" 41 #include "timer.h" 42 #include "descriptor.h" 43 #include "prompt.h" 44 45 46 #define RESTVAL(t) \ 47 ((t).it_value.tv_sec * SECTICKS + (t).it_value.tv_usec / TICKUNIT + \ 48 ((((t).it_value.tv_usec % TICKUNIT) >= (TICKUNIT >> 1)) ? 1 : 0)) 49 50 static struct pppTimer *TimerList = NULL, *ExpiredList = NULL; 51 52 static void StopTimerNoBlock(struct pppTimer *); 53 54 static const char * 55 tState2Nam(u_int state) 56 { 57 static const char * const StateNames[] = { "stopped", "running", "expired" }; 58 59 if (state >= sizeof StateNames / sizeof StateNames[0]) 60 return "unknown"; 61 return StateNames[state]; 62 } 63 64 void 65 timer_Stop(struct pppTimer *tp) 66 { 67 sigset_t mask, omask; 68 69 sigemptyset(&mask); 70 sigaddset(&mask, SIGALRM); 71 sigprocmask(SIG_BLOCK, &mask, &omask); 72 StopTimerNoBlock(tp); 73 sigprocmask(SIG_SETMASK, &omask, NULL); 74 } 75 76 void 77 timer_Start(struct pppTimer *tp) 78 { 79 struct itimerval itimer; 80 struct pppTimer *t, *pt; 81 u_long ticks = 0; 82 sigset_t mask, omask; 83 84 sigemptyset(&mask); 85 sigaddset(&mask, SIGALRM); 86 sigprocmask(SIG_BLOCK, &mask, &omask); 87 88 if (tp->state != TIMER_STOPPED) 89 StopTimerNoBlock(tp); 90 91 if (tp->load == 0) { 92 log_Printf(LogTIMER, "%s timer[%p] has 0 load!\n", tp->name, tp); 93 sigprocmask(SIG_SETMASK, &omask, NULL); 94 return; 95 } 96 97 /* 98 * We just need to insert tp in the correct relative place. We don't 99 * need to adjust TimerList->rest (yet). 100 */ 101 if (TimerList && getitimer(ITIMER_REAL, &itimer) == 0) 102 ticks = RESTVAL(itimer) - TimerList->rest; 103 104 pt = NULL; 105 for (t = TimerList; t; t = t->next) { 106 if (ticks + t->rest >= tp->load) 107 break; 108 ticks += t->rest; 109 pt = t; 110 } 111 112 tp->state = TIMER_RUNNING; 113 tp->rest = tp->load - ticks; 114 115 if (t) 116 log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p] before %s " 117 "timer[%p], delta = %ld\n", tp->name, tp, t->name, t, tp->rest); 118 else 119 log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p]\n", tp->name, tp); 120 121 /* Insert given *tp just before *t */ 122 tp->next = t; 123 if (pt) { 124 pt->next = tp; 125 } else { 126 TimerList = tp; 127 timer_InitService(t != NULL); /* [re]Start the Timer Service */ 128 } 129 if (t) 130 t->rest -= tp->rest; 131 132 sigprocmask(SIG_SETMASK, &omask, NULL); 133 } 134 135 static void 136 StopTimerNoBlock(struct pppTimer *tp) 137 { 138 struct itimerval itimer; 139 struct pppTimer *t, *pt; 140 141 /* 142 * A RUNNING timer must be removed from TimerList (->next list). 143 * A STOPPED timer isn't in any list, but may have a bogus [e]next field. 144 * An EXPIRED timer is in the ->enext list. 145 */ 146 147 if (tp->state == TIMER_STOPPED) 148 return; 149 150 pt = NULL; 151 for (t = TimerList; t != tp && t != NULL; t = t->next) 152 pt = t; 153 154 if (t) { 155 if (pt) 156 pt->next = t->next; 157 else { 158 TimerList = t->next; 159 if (TimerList == NULL) /* Last one ? */ 160 timer_TermService(); /* Terminate Timer Service */ 161 } 162 if (t->next) { 163 if (!pt && getitimer(ITIMER_REAL, &itimer) == 0) 164 t->next->rest += RESTVAL(itimer); /* t (tp) was the first in the list */ 165 else 166 t->next->rest += t->rest; 167 if (!pt && t->next->rest > 0) /* t->next is now the first in the list */ 168 timer_InitService(1); 169 } 170 } else { 171 /* Search for any pending expired timers */ 172 pt = NULL; 173 for (t = ExpiredList; t != tp && t != NULL; t = t->enext) 174 pt = t; 175 176 if (t) { 177 if (pt) 178 pt->enext = t->enext; 179 else 180 ExpiredList = t->enext; 181 } else if (tp->state == TIMER_RUNNING) 182 log_Printf(LogERROR, "Oops, %s timer not found!!\n", tp->name); 183 } 184 185 tp->next = tp->enext = NULL; 186 tp->state = TIMER_STOPPED; 187 } 188 189 static void 190 TimerService(void) 191 { 192 struct pppTimer *tp, *exp, *next; 193 194 if (log_IsKept(LogTIMER)) { 195 static time_t t; /* Only show timers globally every second */ 196 time_t n = time(NULL); 197 198 if (n > t) 199 timer_Show(LogTIMER, NULL); 200 t = n; 201 } 202 203 tp = TimerList; 204 if (tp) { 205 tp->rest = 0; 206 207 /* Multiple timers might expire at once. Create a list of expired timers */ 208 exp = NULL; 209 do { 210 tp->state = TIMER_EXPIRED; 211 next = tp->next; 212 tp->enext = exp; 213 exp = tp; 214 tp = next; 215 } while (tp && tp->rest == 0); 216 217 TimerList = tp; 218 if (TimerList != NULL) /* Any timers remaining ? */ 219 timer_InitService(1); /* Restart the Timer Service */ 220 else 221 timer_TermService(); /* Stop the Timer Service */ 222 223 /* Process all expired timers */ 224 while (exp) { 225 ExpiredList = exp->enext; 226 exp->enext = NULL; 227 if (exp->func) 228 (*exp->func)(exp->arg); 229 exp = ExpiredList; 230 } 231 } 232 } 233 234 void 235 timer_Show(int LogLevel, struct prompt *prompt) 236 { 237 struct itimerval itimer; 238 struct pppTimer *pt; 239 long rest; 240 241 /* 242 * Adjust the base time so that the deltas reflect what's really 243 * happening. Changing TimerList->rest might cause it to become zero 244 * (if getitimer() returns a value close to zero), and the 245 * timer_InitService() call will call setitimer() with zero it_value, 246 * stopping the itimer... so be careful! 247 */ 248 if (TimerList && getitimer(ITIMER_REAL, &itimer) == 0) 249 rest = RESTVAL(itimer) - TimerList->rest; 250 else 251 rest = 0; 252 253 #define SECS(val) ((val) / SECTICKS) 254 #define HSECS(val) (((val) % SECTICKS) * 100 / SECTICKS) 255 #define DISP \ 256 "%s timer[%p]: freq = %ld.%02lds, next = %lu.%02lus, state = %s\n", \ 257 pt->name, pt, SECS(pt->load), HSECS(pt->load), SECS(rest), \ 258 HSECS(rest), tState2Nam(pt->state) 259 260 if (!prompt) 261 log_Printf(LogLevel, "---- Begin of Timer Service List---\n"); 262 263 for (pt = TimerList; pt; pt = pt->next) { 264 rest += pt->rest; 265 if (prompt) 266 prompt_Printf(prompt, DISP); 267 else 268 log_Printf(LogLevel, DISP); 269 } 270 271 if (!prompt) 272 log_Printf(LogLevel, "---- End of Timer Service List ---\n"); 273 } 274 275 void 276 timer_InitService(int restart) 277 { 278 struct itimerval itimer; 279 280 if (TimerList) { 281 if (!restart) 282 sig_signal(SIGALRM, (void (*)(int))TimerService); 283 itimer.it_interval.tv_sec = 0; 284 itimer.it_interval.tv_usec = 0; 285 itimer.it_value.tv_sec = TimerList->rest / SECTICKS; 286 itimer.it_value.tv_usec = (TimerList->rest % SECTICKS) * TICKUNIT; 287 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 288 log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno)); 289 } 290 } 291 292 void 293 timer_TermService(void) 294 { 295 struct itimerval itimer; 296 297 itimer.it_interval.tv_usec = itimer.it_interval.tv_sec = 0; 298 itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0; 299 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 300 log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno)); 301 sig_signal(SIGALRM, SIG_IGN); 302 } 303