timer.c revision 37061
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 1.29 1998/06/15 19:06:56 brian Exp $ 21 * 22 * TODO: 23 */ 24 25#include <errno.h> 26#include <signal.h> 27#include <stdio.h> 28#include <sys/time.h> 29#include <termios.h> 30#include <unistd.h> 31 32#include "log.h" 33#include "sig.h" 34#include "timer.h" 35#include "descriptor.h" 36#include "prompt.h" 37 38static struct pppTimer *TimerList = NULL; 39 40static void StopTimerNoBlock(struct pppTimer *); 41 42static const char * 43tState2Nam(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 52void 53timer_Stop(struct pppTimer * tp) 54{ 55 int omask; 56 57 omask = sigblock(sigmask(SIGALRM)); 58 StopTimerNoBlock(tp); 59 sigsetmask(omask); 60} 61 62void 63timer_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 timer_InitService(); 102 TimerList = tp; 103 } 104 if (t) 105 t->rest -= tp->rest; 106 107 sigsetmask(omask); 108} 109 110static void 111StopTimerNoBlock(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 145static void 146TimerService(void) 147{ 148 struct pppTimer *tp, *exp, *wt; 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 tp = TimerList; 159 if (tp) { 160 tp->rest--; 161 if (tp->rest == 0) { 162 163 /* 164 * Multiple timers may expires at once. Create list of expired timers. 165 */ 166 exp = NULL; 167 do { 168 tp->state = TIMER_EXPIRED; 169 wt = tp->next; 170 tp->enext = exp; 171 exp = tp; 172 tp = wt; 173 } while (tp && (tp->rest == 0)); 174 175 TimerList = tp; 176 if (TimerList == NULL) /* No timers ? */ 177 timer_TermService(); /* Terminate Timer Service */ 178 179 /* 180 * Process all expired timers. 181 */ 182 while (exp) { 183#ifdef notdef 184 timer_Stop(exp); 185#endif 186 if (exp->func) 187 (*exp->func) (exp->arg); 188 189 /* 190 * Just Removing each item from expired list And exp->enext will be 191 * intialized at next expire in this funtion. 192 */ 193 exp = exp->enext; 194 } 195 } 196 } 197} 198 199void 200timer_Show(int LogLevel, struct prompt *prompt) 201{ 202 struct pppTimer *pt; 203 int rest = 0; 204 205#define SECS(val) ((val) / SECTICKS) 206#define HSECS(val) (((val) % SECTICKS) * 100 / SECTICKS) 207#define DISP \ 208 "%s timer[%p]: freq = %ld.%02lds, next = %d.%02ds, state = %s\n", \ 209 pt->name, pt, SECS(pt->load), HSECS(pt->load), SECS(rest), \ 210 HSECS(rest), tState2Nam(pt->state) 211 212 if (!prompt) 213 log_Printf(LogLevel, "---- Begin of Timer Service List---\n"); 214 215 for (pt = TimerList; pt; pt = pt->next) { 216 rest += pt->rest; 217 if (prompt) 218 prompt_Printf(prompt, DISP); 219 else 220 log_Printf(LogLevel, DISP); 221 } 222 223 if (!prompt) 224 log_Printf(LogLevel, "---- End of Timer Service List ---\n"); 225} 226 227void 228timer_InitService() 229{ 230 struct itimerval itimer; 231 232 sig_signal(SIGALRM, (void (*) (int)) TimerService); 233 itimer.it_interval.tv_sec = itimer.it_value.tv_sec = 0; 234 itimer.it_interval.tv_usec = itimer.it_value.tv_usec = TICKUNIT; 235 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 236 log_Printf(LogERROR, "Unable to set itimer.\n"); 237} 238 239void 240timer_TermService(void) 241{ 242 struct itimerval itimer; 243 244 itimer.it_interval.tv_usec = itimer.it_interval.tv_sec = 0; 245 itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0; 246 if (setitimer(ITIMER_REAL, &itimer, NULL) == -1) 247 log_Printf(LogERROR, "Unable to set itimer.\n"); 248 sig_signal(SIGALRM, SIG_IGN); 249} 250