1 /* 2 * PPP Timer Processing Module 3 * 4 * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5 * 6 * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the Internet Initiative Japan, Inc. The name of the 14 * IIJ may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $Id: timer.c,v 1.33 1999/05/09 20:02:28 brian Exp $ 21 * 22 * TODO: 23 */ 24 25 #include <errno.h> 26 #include <signal.h> 27 #include <stdio.h> 28 #include <string.h> 29 #include <sys/time.h> 30 #include <termios.h> 31 32 #include "log.h" 33 #include "sig.h" 34 #include "timer.h" 35 #include "descriptor.h" 36 #include "prompt.h" 37 38 static struct pppTimer *TimerList = NULL; 39 40 static void StopTimerNoBlock(struct pppTimer *); 41 42 static const char * 43 tState2Nam(u_int state) 44 { 45 static const char *StateNames[] = { "stopped", "running", "expired" }; 46 47 if (state >= sizeof StateNames / sizeof StateNames[0]) 48 return "unknown"; 49 return StateNames[state]; 50 } 51 52 void 53 timer_Stop(struct pppTimer *tp) 54 { 55 int omask; 56 57 omask = sigblock(sigmask(SIGALRM)); 58 StopTimerNoBlock(tp); 59 sigsetmask(omask); 60 } 61 62 void 63 timer_Start(struct pppTimer *tp) 64 { 65 struct pppTimer *t, *pt; 66 u_long ticks = 0; 67 int omask; 68 69 omask = sigblock(sigmask(SIGALRM)); 70 71 if (tp->state != TIMER_STOPPED) 72 StopTimerNoBlock(tp); 73 74 if (tp->load == 0) { 75 log_Printf(LogTIMER, "%s timer[%p] has 0 load!\n", tp->name, tp); 76 sigsetmask(omask); 77 return; 78 } 79 pt = NULL; 80 for (t = TimerList; t; t = t->next) { 81 if (ticks + t->rest >= tp->load) 82 break; 83 ticks += t->rest; 84 pt = t; 85 } 86 87 tp->state = TIMER_RUNNING; 88 tp->rest = tp->load - ticks; 89 90 if (t) 91 log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p] before %s " 92 "timer[%p], delta = %ld\n", tp->name, tp, t->name, t, tp->rest); 93 else 94 log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p]\n", tp->name, tp); 95 96 /* Insert given *tp just before *t */ 97 tp->next = t; 98 if (pt) { 99 pt->next = tp; 100 } else { 101 TimerList = tp; 102 timer_InitService(0); /* Start the Timer Service */ 103 } 104 if (t) 105 t->rest -= tp->rest; 106 107 sigsetmask(omask); 108 } 109 110 static void 111 StopTimerNoBlock(struct pppTimer *tp) 112 { 113 struct pppTimer *t, *pt; 114 115 /* 116 * A RUNNING timer must be removed from TimerList (->next list). 117 * A STOPPED timer isn't in any list, but may have a bogus [e]next field. 118 * An EXPIRED timer is in the ->enext list. 119 */ 120 if (tp->state != TIMER_RUNNING) { 121 tp->next = NULL; 122 tp->state = TIMER_STOPPED; 123 return; 124 } 125 pt = NULL; 126 for (t = TimerList; t != tp && t != NULL; t = t->next) 127 pt = t; 128 if (t) { 129 if (pt) { 130 pt->next = t->next; 131 } else { 132 TimerList = t->next; 133 if (TimerList == NULL) /* Last one ? */ 134 timer_TermService(); /* Terminate Timer Service */ 135 } 136 if (t->next) 137 t->next->rest += tp->rest; 138 } else 139 log_Printf(LogERROR, "Oops, %s timer not found!!\n", tp->name); 140 141 tp->next = NULL; 142 tp->state = TIMER_STOPPED; 143 } 144 145 static void 146 TimerService(void) 147 { 148 struct pppTimer *tp, *exp, *next; 149 150 if (log_IsKept(LogTIMER)) { 151 static time_t t; /* Only show timers globally every second */ 152 time_t n = time(NULL); 153 154 if (n > t) 155 timer_Show(LogTIMER, NULL); 156 t = n; 157 } 158 159 tp = TimerList; 160 if (tp) { 161 tp->rest = 0; 162 163 /* Multiple timers might expire at once. Create a list of expired timers */ 164 exp = NULL; 165 do { 166 tp->state = TIMER_EXPIRED; 167 next = tp->next; 168 tp->enext = exp; 169 exp = tp; 170 tp = next; 171 } while (tp && tp->rest == 0); 172 173 TimerList = tp; 174 if (TimerList != NULL) /* Any timers remaining ? */ 175 timer_InitService(1); /* Restart the Timer Service */ 176 else 177 timer_TermService(); /* Stop the Timer Service */ 178 179 /* Process all expired timers */ 180 while (exp) { 181 next = exp->enext; 182 exp->enext = NULL; 183 if (exp->func) 184 (*exp->func)(exp->arg); 185 exp = next; 186 } 187 } 188 } 189 190 void 191 timer_Show(int LogLevel, struct prompt *prompt) 192 { 193 struct itimerval itimer; 194 struct pppTimer *pt; 195 u_long rest = 0; 196 197 /* Adjust our first delta so that it reflects what's really happening */ 198 if (TimerList && getitimer(ITIMER_REAL, &itimer) == 0) 199 TimerList->rest = itimer.it_value.tv_sec * SECTICKS + 200 itimer.it_value.tv_usec / TICKUNIT; 201 202 #define SECS(val) ((val) / SECTICKS) 203 #define HSECS(val) (((val) % SECTICKS) * 100 / SECTICKS) 204 #define DISP \ 205 "%s timer[%p]: freq = %ld.%02lds, next = %lu.%02lus, state = %s\n", \ 206 pt->name, pt, SECS(pt->load), HSECS(pt->load), SECS(rest), \ 207 HSECS(rest), tState2Nam(pt->state) 208 209 if (!prompt) 210 log_Printf(LogLevel, "---- Begin of Timer Service List---\n"); 211 212 for (pt = TimerList; pt; pt = pt->next) { 213 rest += pt->rest; 214 if (prompt) 215 prompt_Printf(prompt, DISP); 216 else 217 log_Printf(LogLevel, DISP); 218 } 219 220 if (!prompt) 221 log_Printf(LogLevel, "---- End of Timer Service List ---\n"); 222 } 223 224 void 225 timer_InitService(int restart) 226 { 227 struct itimerval itimer; 228 229 if (TimerList) { 230 if (!restart) 231 sig_signal(SIGALRM, (void (*)(int))TimerService); 232 itimer.it_interval.tv_sec = 0; 233 itimer.it_interval.tv_usec = 0; 234 itimer.it_value.tv_sec = TimerList->rest / SECTICKS; 235 itimer.it_value.tv_usec = (TimerList->rest % SECTICKS) * TICKUNIT; 236 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 237 log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno)); 238 } 239 } 240 241 void 242 timer_TermService(void) 243 { 244 struct itimerval itimer; 245 246 itimer.it_interval.tv_usec = itimer.it_interval.tv_sec = 0; 247 itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0; 248 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 249 log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno)); 250 sig_signal(SIGALRM, SIG_IGN); 251 } 252