-/*
- * timer.c --- daemon to provide a tagged interval timer service
- *
- * This little daemon runs forever waiting for signals. SIGIO (or SIGUSR1)
- * causes it to read an event spec from stdin; that is, a date followed by
- * colon followed by an event label. SIGALRM causes it to check its queue
- * for events attached to the current second; if one is found, its label
- * is written to stdout. SIGTERM causes it to terminate, printing a list
- * of pending events.
- *
- * This program is intended to be used with the lisp package called timer.el.
- * It was written anonymously in 1990. This version was documented and
- * rewritten for portability by esr@snark,thyrsus.com, Aug 7 1992.
- */
-#include <stdio.h>
-#include <signal.h>
-#include <fcntl.h> /* FASYNC */
-#include <sys/types.h> /* time_t */
-
-#include "../src/config.h"
-#ifdef USG
-#undef SIGIO
-#define SIGIO SIGUSR1
-#endif
-
-extern int errno;
-extern char *sys_errlist[], *malloc();
-extern time_t time();
-
-#define MAXEVENTS 256
-
-/*
- * The field separator for input. This character shouldn't be legal in a date,
- * and should be printable so event strings are readable by people. Was
- * originally ';', then got changed to bogus `\001'.
- */
-#define FS '@'
-
-struct event
-{
- char *token;
- time_t reply_at;
-}
-events[MAXEVENTS];
-
-char *pname; /* programme name for error messages */
-
-/* Accepts a string of two fields seperated by FS.
- * First field is string for getdate, saying when to wake-up.
- * Second field is a token to identify the request.
- */
-void schedule(str)
- char *str;
-{
- extern time_t getdate();
- extern char *strcpy();
- time_t now;
- register char *p;
- static struct event *ep;
-
-#ifdef DEBUG
- (void) fprintf(stderr, "Timer sees: %s", str);
-#endif /* DEBUG */
-
- /* check entry format */
- for(p = str; *p && *p != FS; p++)
- continue;
- if (!*p)
- {
- (void)fprintf(stderr, "%s: bad input format: %s", pname, str);
- return;
- }
- *p++ = 0;
-
- /* allocate an event slot */
- for(ep = events; ep < events + MAXEVENTS; ep++)
- if (ep->token == (char *)NULL)
- break;
- if (ep == events + MAXEVENTS)
- (void) fprintf(stderr, "%s: too many events: %s", pname, str);
-
- /* don't allow users to schedule events in past time */
- else if ((ep->reply_at = get_date(str, NULL)) - time(&now) < 0)
- (void)fprintf(stderr, "%s: bad time spec: %s%c%s", pname, str, FS, p);
-
- /* save the event description */
- else if ((ep->token = malloc((unsigned)strlen(p) + 1)) == NULL)
- (void)fprintf(stderr, "%s: malloc %s: %s%c%s",
- pname, sys_errlist[errno], str, FS, p);
- else
- {
- (void)strcpy(ep->token, p);
-
-#ifdef DEBUG
- (void) fprintf(stderr,
- "New event: %ld: %s", ep->reply_at, ep->token);
-#endif /* DEBUG */
- }
-}
-
-void
-notify()
-{
- time_t now, tdiff, waitfor = -1;
- register struct event *ep;
-
- now = time((time_t *)NULL);
-
- for(ep = events; ep < events + MAXEVENTS; ep++)
- if (ep->token)
- {
- /* any events ready to fire? */
- if (ep->reply_at <= now)
- {
-#ifdef DEBUG
- (void) fprintf(stderr,
- "Event %d firing: %ld @ %s",
- (ep - events), ep->reply_at, ep->token);
-#endif /* DEBUG */
- (void)fputs(ep->token, stdout);
- free(ep->token);
- ep->token = (char *)NULL;
- }
- else
- {
-#ifdef DEBUG
- (void) fprintf(stderr,
- "Event %d still waiting: %ld @ %s",
- (ep - events), ep->reply_at, ep->token);
-#endif /* DEBUG */
-
- /* next timeout should be the soonest of any remaining */
- if ((tdiff = ep->reply_at - now) < waitfor || waitfor < 0)
- waitfor = (long)tdiff;
- }
- }
-
- /* If there's no more events, SIGIO should be next wake-up */
- if (waitfor != -1)
- {
-#ifdef DEBUG
- (void) fprintf(stderr,
- "Setting %d-second alarm\n", waitfor);
-#endif /* DEBUG */
- (void)alarm(waitfor);
- }
-}
-
-void
-getevent()
-{
- extern char *fgets();
- struct event *ep;
- char buf[BUFSIZ];
-
- /* in principle the itimer should be disabled on entry to this function,
- but it really doesn't make any important difference if it isn't */
-
- if (fgets(buf, sizeof(buf), stdin) == NULL)
- exit(0);
-
- /* register the event */
- schedule(buf);
-
- /* Who knows what this interrupted, or if it said "now"? */
- notify();
-}
-
-void
-sigcatch(sig)
-/* dispatch on incoming signal, then restore it */
-{
- struct event *ep;
-
- switch(sig)
- {
- case SIGALRM:
-#ifdef DEBUG
- (void) fprintf(stderr, "Alarm signal received\n");
-#endif /* DEBUG */
- notify();
- break;
- case SIGIO:
- getevent();
- break;
- case SIGTERM:
- (void) fprintf(stderr, "Events still queued:\n");
- for (ep = events; ep < events + MAXEVENTS; ep++)
- if (ep->token)
- (void) fprintf(stderr, "%d = %ld @ %s",
- ep - events, ep->reply_at, ep->token);
- exit(0);
- break;
- }
-
- /* required on older UNIXes; harmless on newer ones */
- (void) signal(sig, sigcatch);
-}
-
-/*ARGSUSED*/
-int
-main(argc, argv)
- int argc;
- char **argv;
-{
- for (pname = argv[0] + strlen(argv[0]); *pname != '/' && pname != argv[0];
- pname--);
- if (*pname == '/') pname++;
-
- (void)signal(SIGIO, sigcatch);
- (void)signal(SIGALRM, sigcatch);
- (void)signal(SIGTERM, sigcatch);
-
-#ifndef USG
- (void)fcntl(0, F_SETFL, FASYNC);
-#endif /* USG */
-
- while (1) pause();
-}
-
-/* timer.c ends here */
+/* timer.c --- daemon to provide a tagged interval timer service
+
+ This little daemon runs forever waiting for signals. SIGIO (or
+ SIGUSR1) causes it to read an event spec from stdin; that is, a
+ date followed by colon followed by an event label. SIGALRM causes
+ it to check its queue for events attached to the current second; if
+ one is found, its label is written to stdout. SIGTERM causes it to
+ terminate, printing a list of pending events.
+
+ This program is intended to be used with the lisp package called
+ timer.el. It was written anonymously in 1990. This version was
+ documented and rewritten for portability by esr@snark,thyrsus.com,
+ Aug 7 1992. */
+
+#include <stdio.h>
+#include <signal.h>
+#include <fcntl.h> /* FASYNC */
+#include <sys/types.h> /* time_t */
+
+#include "../src/config.h"
+#ifdef USG
+#undef SIGIO
+#define SIGIO SIGUSR1
+#endif
+
+extern int errno;
+extern char *sys_errlist[], *malloc ();
+extern time_t time ();
+
+/*
+ * The field separator for input. This character shouldn't be legal in a date,
+ * and should be printable so event strings are readable by people. Was
+ * originally ';', then got changed to bogus `\001'.
+ */
+#define FS '@'
+
+struct event
+ {
+ char *token;
+ time_t reply_at;
+ };
+int events_size; /* How many slots have we allocated? */
+int num_events; /* How many are actually scheduled? */
+struct event *events; /* events[0 .. num_events-1] are the
+ valid events. */
+
+char *pname; /* programme name for error messages */
+
+/* Accepts a string of two fields seperated by FS.
+ First field is string for getdate, saying when to wake-up.
+ Second field is a token to identify the request. */
+void
+schedule (str)
+ char *str;
+{
+ extern time_t getdate ();
+ extern char *strcpy ();
+ time_t now;
+ register char *p;
+ static struct event *ep;
+
+ /* check entry format */
+ for (p = str; *p && *p != FS; p++)
+ continue;
+ if (!*p)
+ {
+ fprintf (stderr, "%s: bad input format: %s", pname, str);
+ return;
+ }
+ *p++ = 0;
+
+ /* allocate an event slot */
+ ep = events + num_events;
+
+ /* If the event array is full, stretch it. After stretching, we know
+ that ep will be pointing to an available event spot. */
+ if (ep == events + events_size)
+ {
+ int old_size = events_size;
+
+ events_size *= 2;
+ events = ((struct event *)
+ realloc (events, events_size * sizeof (struct event)));
+ if (! events)
+ {
+ fprintf (stderr, "%s: virtual memory exhausted.\n", pname);
+
+ /* Should timer exit now? Well, we've still got other
+ events in the queue, and more memory might become
+ available in the future, so we'll just toss this event.
+ This will screw up whoever scheduled the event, but
+ maybe someone else will survive. */
+ return;
+ }
+
+ while (old_size < events_size)
+ events[old_size++].token = NULL;
+ }
+
+ /* Don't allow users to schedule events in past time. */
+ ep->reply_at = get_date (str, NULL);
+ if (ep->reply_at - time (&now) < 0)
+ {
+ fprintf (stderr, "%s: bad time spec: %s%c%s", pname, str, FS, p);
+ return;
+ }
+
+ /* save the event description */
+ ep->token = (char *) malloc ((unsigned) strlen (p) + 1);
+ if (! ep->token)
+ {
+ fprintf (stderr, "%s: malloc %s: %s%c%s",
+ pname, sys_errlist[errno], str, FS, p);
+ return;
+ }
+
+ strcpy (ep->token, p);
+ num_events++;
+}
+
+void
+notify ()
+{
+ time_t now, tdiff, waitfor;
+ register struct event *ep;
+
+ now = time ((time_t *) NULL);
+
+ for (ep = events; ep < events + num_events; ep++)
+ /* Are any events ready to fire? */
+ if (ep->reply_at <= now)
+ {
+ fputs (ep->token, stdout);
+ free (ep->token);
+
+ /* We now have a hole in the event array; fill it with the last
+ event. */
+ ep->token = events[num_events].token;
+ ep->reply_at = events[num_events].reply_at;
+ num_events--;
+
+ /* We ought to scan this event again. */
+ ep--;
+ }
+ else
+ {
+ /* next timeout should be the soonest of any remaining */
+ if ((tdiff = ep->reply_at - now) < waitfor || waitfor < 0)
+ waitfor = (long)tdiff;
+ }
+
+ /* If there are no more events, we needn't bother setting an alarm. */
+ if (num_events > 0)
+ alarm (waitfor);
+}
+
+void
+getevent ()
+{
+ int i;
+ char *buf;
+ int buf_size;
+
+ /* In principle the itimer should be disabled on entry to this
+ function, but it really doesn't make any important difference
+ if it isn't. */
+
+ buf_size = 80;
+ buf = (char *) malloc (buf_size);
+
+ /* Read a line from standard input, expanding buf if it is too short
+ to hold the line. */
+ for (i = 0; ; i++)
+ {
+ int c;
+
+ if (i >= buf_size)
+ {
+ buf_size *= 2;
+ buf = (char *) realloc (buf, buf_size);
+
+ /* If we're out of memory, toss this event. */
+ do
+ {
+ c = getchar ();
+ }
+ while (c != '\n' && c != EOF);
+
+ return;
+ }
+
+ c = getchar ();
+
+ if (c == EOF)
+ exit (0);
+
+ if (c == '\n')
+ {
+ buf[i] = '\0';
+ break;
+ }
+
+ buf[i] = c;
+ }
+
+ /* Register the event. */
+ schedule (buf);
+ free (buf);
+
+ /* Who knows what this interrupted, or if it said "now"? */
+ notify ();
+}
+
+void
+sigcatch (sig)
+ int sig;
+/* dispatch on incoming signal, then restore it */
+{
+ struct event *ep;
+
+ switch (sig)
+ {
+ case SIGALRM:
+ notify ();
+ break;
+ case SIGIO:
+ getevent ();
+ break;
+ case SIGTERM:
+ fprintf (stderr, "Events still queued:\n");
+ for (ep = events; ep < events + num_events; ep++)
+ fprintf (stderr, "%d = %ld @ %s",
+ ep - events, ep->reply_at, ep->token);
+ exit (0);
+ break;
+ }
+
+ /* required on older UNIXes; harmless on newer ones */
+ signal (sig, sigcatch);
+}
+
+/*ARGSUSED*/
+int
+main (argc, argv)
+ int argc;
+ char **argv;
+{
+ for (pname = argv[0] + strlen (argv[0]);
+ *pname != '/' && pname != argv[0];
+ pname--);
+ if (*pname == '/')
+ pname++;
+
+ events_size = 16;
+ events = ((struct event *) malloc (events_size * sizeof (*events)));
+ num_events = 0;
+
+ signal (SIGIO, sigcatch);
+ signal (SIGALRM, sigcatch);
+ signal (SIGTERM, sigcatch);
+
+#ifndef USG
+ fcntl (0, F_SETFL, FASYNC);
+#endif /* USG */
+
+ while (1) pause ();
+}
+
+/* timer.c ends here */
HCoop / bpt / emacs.git / commitdiff