diff options
-rw-r--r-- | contrib/libbegemot/rpoll.c | 1428 |
1 files changed, 714 insertions, 714 deletions
diff --git a/contrib/libbegemot/rpoll.c b/contrib/libbegemot/rpoll.c index 7a3cb11..b598663 100644 --- a/contrib/libbegemot/rpoll.c +++ b/contrib/libbegemot/rpoll.c @@ -1,714 +1,714 @@ -/*
- * Copyright (c)1996-2002 by Hartmut Brandt
- * All rights reserved.
- *
- * Author: Hartmut Brandt
- *
- * Redistribution of this software and documentation and use in source and
- * binary forms, with or without modification, are permitted provided that
- * the following conditions are met:
- *
- * 1. Redistributions of source code or documentation must retain the above
- * copyright notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE AND DOCUMENTATION IS PROVIDED BY THE AUTHOR
- * AND ITS CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
- * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
- * THE AUTHOR OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
- * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-/*
- * These functions try to hide the poll/select/setitimer interface from the
- * user. You associate callback functions with file descriptors and timers.
- *
- * $Begemot: libbegemot/rpoll.c,v 1.14 2004/09/21 15:59:00 brandt Exp $
- */
-# include <stdio.h>
-# include <stdlib.h>
-# include <stddef.h>
-# include <stdarg.h>
-# include <signal.h>
-# include <string.h>
-# include <errno.h>
-# include <time.h>
-# include <assert.h>
-# include <unistd.h>
-# include <sys/time.h>
-
-/*
- * There happens to be linuxes which read siginfo.h when including
- * signal.h, which, for no appearent reason, defines these symbols.
- */
-# ifdef POLL_IN
-# undef POLL_IN
-# endif
-# ifdef POLL_OUT
-# undef POLL_OUT
-# endif
-
-# include "rpoll.h"
-
-/*
-# define DEBUG
-*/
-
-# ifdef USE_POLL
-# ifdef NEED_POLL_XOPEN_TWIDDLE
-# define __USE_XOPEN
-# endif
-# include <poll.h>
-# ifdef NEED_POLL_XOPEN_TWIDDLE
-# undef __USE_XOPEN
-# endif
-# include <stropts.h>
-# endif
-
-/*
- * the second define is for Linux, which sometimes fails to
- * declare INFTIM.
- */
-# if defined(USE_SELECT) || !defined(INFTIM)
-# define INFTIM (-1)
-# endif
-
-# if defined(SIGPOLL)
-# define SIGNAL SIGPOLL
-# else
-# if defined(SIGIO)
-# define SIGNAL SIGIO
-# endif
-# endif
-
-# ifdef USE_POLL
-# define poll_in (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI)
-# define poll_out (POLLOUT | POLLWRNORM | POLLWRBAND)
-# define poll_except (POLLERR | POLLHUP)
-# endif
-
-# ifdef BROKEN_SELECT_PROTO
-# define SELECT_CAST(P) (int *)P
-# else
-# define SELECT_CAST(P) P
-# endif
-
-
-typedef signed long long tval_t;
-
-static inline tval_t GETMSECS(void);
-
-static inline tval_t
-GETMSECS(void) {
- struct timeval tval;
-
- (void)gettimeofday(&tval, NULL);
- return (tval_t)tval.tv_sec*1000+tval.tv_usec/1000;
-}
-
-/*
- * Simple fatal exit.
- */
-static void
-_panic(const char *fmt, ...)
-{
- va_list ap;
-
- va_start(ap, fmt);
- fprintf(stderr, "panic: ");
- vfprintf(stderr, fmt, ap);
- fprintf(stderr, "\n");
- va_end(ap);
-
- exit(1);
-}
-
-static void *
-_xrealloc(void *p, size_t s)
-{
- void *ptr;
-
- if(p == NULL) {
- if((ptr=malloc(s)) == NULL && (s!=0 || (ptr=malloc(1)) == NULL))
- _panic("out of memory: xrealloc(%lx, %lu)",
- (unsigned long)p, (unsigned long)s);
- } else if(s == 0) {
- free(p);
- if((ptr=malloc(s)) == NULL && (ptr=malloc(1)) == NULL)
- _panic("out of memory: xrealloc(%lx, %lu)",
- (unsigned long)p, (unsigned long)s);
- } else {
- if((ptr = realloc(p, s)) == NULL)
- _panic("out of memory: xrealloc(%lx, %lu)",
- (unsigned long)p, (unsigned long)s);
- }
-
- return ptr;
-}
-
-/*
- * This structure holds one registration record for files
- */
-typedef struct {
- int fd; /* file descriptor (-1 if struct unused) */
- int mask; /* event flags */
- void * arg; /* client arg */
- poll_f func; /* handler */
-# ifdef USE_POLL
- struct pollfd *pfd; /* pointer to corresponding poll() structure */
-# endif
-} PollReg_t;
-
-/*
- * Now for timers
- */
-typedef struct {
- u_int msecs; /* millisecond value of the timer */
- int repeat; /* one shot or repeat? */
- void *arg; /* client arg */
- timer_f func; /* handler, 0 means disfunct */
- tval_t when; /* next time to trigger in msecs! */
-} PollTim_t;
-
-/* how many records should our table grow at once? */
-# define POLL_REG_GROW 100
-
-# ifdef USE_POLL
-static struct pollfd * pfd; /* fd list for poll() */
-# endif
-
-# ifdef USE_SELECT
-static fd_set rset, wset, xset; /* file descriptor sets for select() */
-static int maxfd; /* maximum fd number */
-# endif
-
-static int in_dispatch;
-
-static PollReg_t * regs; /* registration records */
-static u_int regs_alloc; /* how many are allocated */
-static u_int regs_used; /* upper used limit */
-static sigset_t bset; /* blocked signals */
-static int rebuild; /* rebuild table on next dispatch() */
-
-static int * tfd; /* sorted entries */
-static u_int tfd_alloc; /* number of entries allocated */
-static u_int tfd_used; /* number of entries used */
-static PollTim_t * tims; /* timer registration records */
-static u_int tims_alloc; /* how many are allocated */
-static u_int tims_used; /* how many are used */
-static int resort; /* resort on next dispatch */
-
-int rpoll_trace;
-int rpoll_policy; /* if 0 start sched callbacks from 0 else try round robin */
-
-static void poll_build(void);
-static void poll_blocksig(void);
-static void poll_unblocksig(void);
-static void sort_timers(void);
-
-
-/*
- * Private function to block SIGPOLL or SIGIO for a short time.
- * Don't forget to call poll_unblock before return from the calling function.
- * Don't change the mask between this calls (your changes will be lost).
- */
-static void
-poll_blocksig(void)
-{
- sigset_t set;
-
- sigemptyset(&set);
- sigaddset(&set, SIGNAL);
-
- if(sigprocmask(SIG_BLOCK, &set, &bset))
- _panic("sigprocmask(SIG_BLOCK): %s", strerror(errno));
-}
-
-/*
- * unblock the previously blocked signal
- */
-static void
-poll_unblocksig(void)
-{
- if(sigprocmask(SIG_SETMASK, &bset, NULL))
- _panic("sigprocmask(SIG_SETMASK): %s", strerror(errno));
-}
-
-/*
- * Register the file descriptor fd. If the event corresponding to
- * mask arrives func is called with arg.
- * If fd is already registered with that func and arg, only the mask
- * is changed.
- * We block the IO-signal, so the dispatch function can be called from
- * within the signal handler.
- */
-int
-poll_register(int fd, poll_f func, void *arg, int mask)
-{
- PollReg_t * p;
-
- poll_blocksig();
-
- /* already registered? */
- for(p = regs; p < ®s[regs_alloc]; p++)
- if(p->fd == fd && p->func == func && p->arg == arg) {
- p->mask = mask;
- break;
- }
-
- if(p == ®s[regs_alloc]) {
- /* no - register */
-
- /* find a free slot */
- for(p = regs; p < ®s[regs_alloc]; p++)
- if(p->fd == -1)
- break;
-
- if(p == ®s[regs_alloc]) {
- size_t newsize = regs_alloc + POLL_REG_GROW;
- regs = _xrealloc(regs, sizeof(regs[0]) * newsize);
- for(p = ®s[regs_alloc]; p < ®s[newsize]; p++) {
- p->fd = -1;
-# ifdef USE_POLL
- p->pfd = NULL;
-# endif
- }
- p = ®s[regs_alloc];
- regs_alloc = newsize;
- }
-
- p->fd = fd;
- p->arg = arg;
- p->mask = mask;
- p->func = func;
-
- regs_used++;
- rebuild = 1;
- }
-
- poll_unblocksig();
-
- if(rpoll_trace)
- fprintf(stderr, "poll_register(%d, %#lx, %#lx, %#x)->%d",
- fd, (u_long)func, (u_long)arg, mask, p - regs);
- return p - regs;
-}
-
-/*
- * remove registration
- */
-void
-poll_unregister(int handle)
-{
- if(rpoll_trace)
- fprintf(stderr, "poll_unregister(%d)", handle);
-
- poll_blocksig();
-
- regs[handle].fd = -1;
-# ifdef USE_POLL
- regs[handle].pfd = NULL;
-# endif
- rebuild = 1;
- regs_used--;
-
- poll_unblocksig();
-}
-
-/*
- * Build the structures used by poll() or select()
- */
-static void
-poll_build(void)
-{
- PollReg_t * p;
-
-# ifdef USE_POLL
- struct pollfd * f;
-
- f = pfd = _xrealloc(pfd, sizeof(pfd[0]) * regs_used);
-
- for(p = regs; p < ®s[regs_alloc]; p++)
- if(p->fd >= 0) {
- f->fd = p->fd;
- f->events = 0;
- if(p->mask & POLL_IN)
- f->events |= poll_in;
- if(p->mask & POLL_OUT)
- f->events |= poll_out;
- if(p->mask & POLL_EXCEPT)
- f->events |= poll_except;
- f->revents = 0;
- p->pfd = f++;
- }
- assert(f == &pfd[regs_used]);
-# endif
-
-# ifdef USE_SELECT
- FD_ZERO(&rset);
- FD_ZERO(&wset);
- FD_ZERO(&xset);
- maxfd = -1;
- for(p = regs; p < ®s[regs_alloc]; p++)
- if(p->fd >= 0) {
- if(p->fd > maxfd)
- maxfd = p->fd;
- if(p->mask & POLL_IN)
- FD_SET(p->fd, &rset);
- if(p->mask & POLL_OUT)
- FD_SET(p->fd, &wset);
- if(p->mask & POLL_EXCEPT)
- FD_SET(p->fd, &xset);
- }
-# endif
-}
-
-int
-poll_start_timer(u_int msecs, int repeat, timer_f func, void *arg)
-{
- PollTim_t *p;
-
- /* find unused entry */
- for(p = tims; p < &tims[tims_alloc]; p++)
- if(p->func == NULL)
- break;
-
- if(p == &tims[tims_alloc]) {
- if(tims_alloc == tims_used) {
- size_t newsize = tims_alloc + POLL_REG_GROW;
- tims = _xrealloc(tims, sizeof(tims[0]) * newsize);
- for(p = &tims[tims_alloc]; p < &tims[newsize]; p++)
- p->func = NULL;
- p = &tims[tims_alloc];
- tims_alloc = newsize;
- }
- }
-
- /* create entry */
- p->msecs = msecs;
- p->repeat = repeat;
- p->arg = arg;
- p->func = func;
- p->when = GETMSECS() + msecs;
-
- tims_used++;
-
- resort = 1;
-
- if(rpoll_trace)
- fprintf(stderr, "poll_start_timer(%u, %d, %#lx, %#lx)->%u",
- msecs, repeat, (u_long)func, (u_long)arg, p - tims);
-
- return p - tims;
-}
-
-/*
- * Here we have to look into the sorted table, whether any entry there points
- * into the registration table for the deleted entry. This is needed,
- * because a unregistration can occure while we are scanning through the
- * table in dispatch(). Do this only, if we are really there - resorting
- * will sort out things if we are called from outside the loop.
- */
-void
-poll_stop_timer(int handle)
-{
- u_int i;
-
- if(rpoll_trace)
- fprintf(stderr, "poll_stop_timer(%d)", handle);
-
- tims[handle].func = NULL;
- tims_used--;
-
- resort = 1;
-
- if(!in_dispatch)
- return;
-
- for(i = 0; i < tfd_used; i++)
- if(tfd[i] == handle) {
- tfd[i] = -1;
- break;
- }
-}
-
-/*
- * Squeeze and sort timer table.
- * Should perhaps use a custom sort.
- */
-static int
-tim_cmp(const void *p1, const void *p2)
-{
- int t1 = *(const int *)p1;
- int t2 = *(const int *)p2;
-
- return tims[t1].when < tims[t2].when ? -1
- : tims[t1].when > tims[t2].when ? +1
- : 0;
-}
-
-/*
- * Reconstruct the tfd-array. This will be an sorted array of indexes
- * to the used entries in tims. The next timer to expire will be infront
- * of the array. tfd_used is the number of used entries. The array is
- * re-allocated if needed.
- */
-static void
-sort_timers(void)
-{
- int *pp;
- u_int i;
-
- if(tims_used > tfd_alloc) {
- tfd_alloc = tims_used;
- tfd = _xrealloc(tfd, sizeof(int *) * tfd_alloc);
- }
-
- pp = tfd;
-
- for(i = 0; i < tims_alloc; i++)
- if(tims[i].func)
- *pp++ = i;
- assert(pp - tfd == (ptrdiff_t)tims_used);
-
- tfd_used = tims_used;
- if(tfd_used > 1)
- qsort(tfd, tfd_used, sizeof(int), tim_cmp);
-}
-
-/*
- * Poll the file descriptors and dispatch to the right function
- * If wait is true the poll blocks until somewhat happens.
- * Don't use a pointer here, because the called function may cause
- * a reallocation! The check for pfd != NULL is required, because
- * a sequence of unregister/register could make the wrong callback
- * to be called. So we clear pfd in unregister and check here.
- */
-void
-poll_dispatch(int wait)
-{
- u_int i, idx;
- int ret;
- tval_t now;
- int tout;
- static u_int last_index;
-
-# ifdef USE_SELECT
- fd_set nrset, nwset, nxset;
- struct timeval tv;
-# endif
-
- in_dispatch = 1;
-
- if(rebuild) {
- rebuild = 0;
- poll_build();
- }
- if(resort) {
- resort = 0;
- sort_timers();
- }
-
- /* in wait mode - compute the timeout */
- if(wait) {
- if(tfd_used) {
- now = GETMSECS();
-# ifdef DEBUG
- {
- fprintf(stderr, "now=%"QUADFMT"u", now);
- for(i = 0; i < tims_used; i++)
- fprintf(stderr, "timers[%2d] = %"QUADFMT"d", i, tfd[i]->when - now);
- }
-# endif
- if((tout = tims[tfd[0]].when - now) < 0)
- tout = 0;
- } else
- tout = INFTIM;
- } else
- tout = 0;
-
-# ifdef DEBUG
- fprintf(stderr, "rpoll -- selecting with tout=%u", tout);
-# endif
-
-# ifdef USE_POLL
- ret = poll(pfd, regs_used, tout);
-# endif
-
-# ifdef USE_SELECT
- nrset = rset;
- nwset = wset;
- nxset = xset;
- if(tout != INFTIM) {
- tv.tv_sec = tout / 1000;
- tv.tv_usec = (tout % 1000) * 1000;
- }
- ret = select(maxfd+1,
- SELECT_CAST(&nrset),
- SELECT_CAST(&nwset),
- SELECT_CAST(&nxset), (tout==INFTIM) ? 0 : &tv);
-# endif
-
- if(ret == -1) {
- if(errno == EINTR)
- return;
- _panic("poll/select: %s", strerror(errno));
- }
-
- /* dispatch files */
- if(ret > 0) {
- for(i = 0; i < regs_alloc; i++) {
- idx = rpoll_policy ? ((last_index+i) % regs_alloc) : i;
-
- assert(idx < regs_alloc);
-
- if(regs[idx].fd >= 0) {
- int mask = 0;
-
-# ifdef USE_POLL
- if(regs[idx].pfd) {
- if(regs[idx].pfd->revents & poll_in)
- mask |= POLL_IN;
- if(regs[idx].pfd->revents & poll_out)
- mask |= POLL_OUT;
- if(regs[idx].pfd->revents & poll_except)
- mask |= POLL_EXCEPT;
- }
-# endif
-# ifdef USE_SELECT
- if(FD_ISSET(regs[idx].fd, &nrset))
- mask |= POLL_IN;
- if(FD_ISSET(regs[idx].fd, &nwset))
- mask |= POLL_OUT;
- if(FD_ISSET(regs[idx].fd, &nxset))
- mask |= POLL_EXCEPT;
-# endif
- assert(idx < regs_alloc);
-
- if(mask) {
- if(rpoll_trace)
- fprintf(stderr, "poll_dispatch() -- "
- "file %d/%d",
- regs[idx].fd, idx);
- (*regs[idx].func)(regs[idx].fd, mask, regs[idx].arg);
- }
- }
-
- }
- last_index++;
- }
-
- /* dispatch timeouts */
- if(tfd_used) {
- now = GETMSECS();
- for(i = 0; i < tfd_used; i++) {
- if(tfd[i] < 0)
- continue;
- if(tims[tfd[i]].when > now)
- break;
- if(rpoll_trace)
- fprintf(stderr, "rpoll_dispatch() -- timeout %d",tfd[i]);
- (*tims[tfd[i]].func)(tfd[i], tims[tfd[i]].arg);
- if(tfd[i] < 0)
- continue;
- if(tims[tfd[i]].repeat)
- tims[tfd[i]].when = now + tims[tfd[i]].msecs;
- else {
- tims[tfd[i]].func = NULL;
- tims_used--;
- tfd[i] = -1;
- }
- resort = 1;
- }
- }
- in_dispatch = 0;
-}
-
-
-# ifdef TESTME
-struct timeval start, now;
-int t0, t1;
-
-double elaps(void);
-void infunc(int fd, int mask, void *arg);
-
-double
-elaps(void)
-{
- gettimeofday(&now, NULL);
-
- return (double)(10 * now.tv_sec + now.tv_usec / 100000 - 10 * start.tv_sec - start.tv_usec / 100000)
- / 10;
-}
-
-void
-infunc(int fd, int mask, void *arg)
-{
- char buf[1024];
- int ret;
-
- mask = mask;
- arg = arg;
- if((ret = read(fd, buf, sizeof(buf))) < 0)
- _panic("read: %s", strerror(errno));
- write(1, "stdin:", 6);
- write(1, buf, ret);
-}
-
-void tfunc0(int tid, void *arg);
-void tfunc1(int tid, void *arg);
-
-void
-tfunc0(int tid, void *arg)
-{
- printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg);
-}
-void
-tfunc1(int tid, void *arg)
-{
- printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg);
-}
-
-void first(int tid, void *arg);
-void second(int tid, void *arg);
-
-void
-second(int tid, void *arg)
-{
- printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg);
- poll_start_timer(5500, 0, first, "first");
- poll_stop_timer(t1);
- t0 = poll_start_timer(1000, 1, tfunc0, "1 second");
-}
-void
-first(int tid, void *arg)
-{
- printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg);
- poll_start_timer(3700, 0, second, "second");
- poll_stop_timer(t0);
- t1 = poll_start_timer(250, 1, tfunc1, "1/4 second");
-}
-
-int
-main(int argc, char *argv[])
-{
- argc = argc;
- argv = argv;
- gettimeofday(&start, NULL);
- poll_register(0, infunc, NULL, POLL_IN);
- t0 = poll_start_timer(1000, 1, tfunc0, "1 second");
- poll_start_timer(2500, 0, first, "first");
-
- while(1)
- poll_dispatch(1);
-
- return 0;
-}
-# endif
+/* + * Copyright (c)1996-2002 by Hartmut Brandt + * All rights reserved. + * + * Author: Hartmut Brandt + * + * Redistribution of this software and documentation and use in source and + * binary forms, with or without modification, are permitted provided that + * the following conditions are met: + * + * 1. Redistributions of source code or documentation must retain the above + * copyright notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE AND DOCUMENTATION IS PROVIDED BY THE AUTHOR + * AND ITS CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * THE AUTHOR OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, + * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, + * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +/* + * These functions try to hide the poll/select/setitimer interface from the + * user. You associate callback functions with file descriptors and timers. + * + * $Begemot: libbegemot/rpoll.c,v 1.14 2004/09/21 15:59:00 brandt Exp $ + */ +# include <stdio.h> +# include <stdlib.h> +# include <stddef.h> +# include <stdarg.h> +# include <signal.h> +# include <string.h> +# include <errno.h> +# include <time.h> +# include <assert.h> +# include <unistd.h> +# include <sys/time.h> + +/* + * There happens to be linuxes which read siginfo.h when including + * signal.h, which, for no appearent reason, defines these symbols. + */ +# ifdef POLL_IN +# undef POLL_IN +# endif +# ifdef POLL_OUT +# undef POLL_OUT +# endif + +# include "rpoll.h" + +/* +# define DEBUG +*/ + +# ifdef USE_POLL +# ifdef NEED_POLL_XOPEN_TWIDDLE +# define __USE_XOPEN +# endif +# include <poll.h> +# ifdef NEED_POLL_XOPEN_TWIDDLE +# undef __USE_XOPEN +# endif +# include <stropts.h> +# endif + +/* + * the second define is for Linux, which sometimes fails to + * declare INFTIM. + */ +# if defined(USE_SELECT) || !defined(INFTIM) +# define INFTIM (-1) +# endif + +# if defined(SIGPOLL) +# define SIGNAL SIGPOLL +# else +# if defined(SIGIO) +# define SIGNAL SIGIO +# endif +# endif + +# ifdef USE_POLL +# define poll_in (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI) +# define poll_out (POLLOUT | POLLWRNORM | POLLWRBAND) +# define poll_except (POLLERR | POLLHUP) +# endif + +# ifdef BROKEN_SELECT_PROTO +# define SELECT_CAST(P) (int *)P +# else +# define SELECT_CAST(P) P +# endif + + +typedef signed long long tval_t; + +static inline tval_t GETMSECS(void); + +static inline tval_t +GETMSECS(void) { + struct timeval tval; + + (void)gettimeofday(&tval, NULL); + return (tval_t)tval.tv_sec*1000+tval.tv_usec/1000; +} + +/* + * Simple fatal exit. + */ +static void +_panic(const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + fprintf(stderr, "panic: "); + vfprintf(stderr, fmt, ap); + fprintf(stderr, "\n"); + va_end(ap); + + exit(1); +} + +static void * +_xrealloc(void *p, size_t s) +{ + void *ptr; + + if(p == NULL) { + if((ptr=malloc(s)) == NULL && (s!=0 || (ptr=malloc(1)) == NULL)) + _panic("out of memory: xrealloc(%lx, %lu)", + (unsigned long)p, (unsigned long)s); + } else if(s == 0) { + free(p); + if((ptr=malloc(s)) == NULL && (ptr=malloc(1)) == NULL) + _panic("out of memory: xrealloc(%lx, %lu)", + (unsigned long)p, (unsigned long)s); + } else { + if((ptr = realloc(p, s)) == NULL) + _panic("out of memory: xrealloc(%lx, %lu)", + (unsigned long)p, (unsigned long)s); + } + + return ptr; +} + +/* + * This structure holds one registration record for files + */ +typedef struct { + int fd; /* file descriptor (-1 if struct unused) */ + int mask; /* event flags */ + void * arg; /* client arg */ + poll_f func; /* handler */ +# ifdef USE_POLL + struct pollfd *pfd; /* pointer to corresponding poll() structure */ +# endif +} PollReg_t; + +/* + * Now for timers + */ +typedef struct { + u_int msecs; /* millisecond value of the timer */ + int repeat; /* one shot or repeat? */ + void *arg; /* client arg */ + timer_f func; /* handler, 0 means disfunct */ + tval_t when; /* next time to trigger in msecs! */ +} PollTim_t; + +/* how many records should our table grow at once? */ +# define POLL_REG_GROW 100 + +# ifdef USE_POLL +static struct pollfd * pfd; /* fd list for poll() */ +# endif + +# ifdef USE_SELECT +static fd_set rset, wset, xset; /* file descriptor sets for select() */ +static int maxfd; /* maximum fd number */ +# endif + +static int in_dispatch; + +static PollReg_t * regs; /* registration records */ +static u_int regs_alloc; /* how many are allocated */ +static u_int regs_used; /* upper used limit */ +static sigset_t bset; /* blocked signals */ +static int rebuild; /* rebuild table on next dispatch() */ + +static int * tfd; /* sorted entries */ +static u_int tfd_alloc; /* number of entries allocated */ +static u_int tfd_used; /* number of entries used */ +static PollTim_t * tims; /* timer registration records */ +static u_int tims_alloc; /* how many are allocated */ +static u_int tims_used; /* how many are used */ +static int resort; /* resort on next dispatch */ + +int rpoll_trace; +int rpoll_policy; /* if 0 start sched callbacks from 0 else try round robin */ + +static void poll_build(void); +static void poll_blocksig(void); +static void poll_unblocksig(void); +static void sort_timers(void); + + +/* + * Private function to block SIGPOLL or SIGIO for a short time. + * Don't forget to call poll_unblock before return from the calling function. + * Don't change the mask between this calls (your changes will be lost). + */ +static void +poll_blocksig(void) +{ + sigset_t set; + + sigemptyset(&set); + sigaddset(&set, SIGNAL); + + if(sigprocmask(SIG_BLOCK, &set, &bset)) + _panic("sigprocmask(SIG_BLOCK): %s", strerror(errno)); +} + +/* + * unblock the previously blocked signal + */ +static void +poll_unblocksig(void) +{ + if(sigprocmask(SIG_SETMASK, &bset, NULL)) + _panic("sigprocmask(SIG_SETMASK): %s", strerror(errno)); +} + +/* + * Register the file descriptor fd. If the event corresponding to + * mask arrives func is called with arg. + * If fd is already registered with that func and arg, only the mask + * is changed. + * We block the IO-signal, so the dispatch function can be called from + * within the signal handler. + */ +int +poll_register(int fd, poll_f func, void *arg, int mask) +{ + PollReg_t * p; + + poll_blocksig(); + + /* already registered? */ + for(p = regs; p < ®s[regs_alloc]; p++) + if(p->fd == fd && p->func == func && p->arg == arg) { + p->mask = mask; + break; + } + + if(p == ®s[regs_alloc]) { + /* no - register */ + + /* find a free slot */ + for(p = regs; p < ®s[regs_alloc]; p++) + if(p->fd == -1) + break; + + if(p == ®s[regs_alloc]) { + size_t newsize = regs_alloc + POLL_REG_GROW; + regs = _xrealloc(regs, sizeof(regs[0]) * newsize); + for(p = ®s[regs_alloc]; p < ®s[newsize]; p++) { + p->fd = -1; +# ifdef USE_POLL + p->pfd = NULL; +# endif + } + p = ®s[regs_alloc]; + regs_alloc = newsize; + } + + p->fd = fd; + p->arg = arg; + p->mask = mask; + p->func = func; + + regs_used++; + rebuild = 1; + } + + poll_unblocksig(); + + if(rpoll_trace) + fprintf(stderr, "poll_register(%d, %#lx, %#lx, %#x)->%d", + fd, (u_long)func, (u_long)arg, mask, p - regs); + return p - regs; +} + +/* + * remove registration + */ +void +poll_unregister(int handle) +{ + if(rpoll_trace) + fprintf(stderr, "poll_unregister(%d)", handle); + + poll_blocksig(); + + regs[handle].fd = -1; +# ifdef USE_POLL + regs[handle].pfd = NULL; +# endif + rebuild = 1; + regs_used--; + + poll_unblocksig(); +} + +/* + * Build the structures used by poll() or select() + */ +static void +poll_build(void) +{ + PollReg_t * p; + +# ifdef USE_POLL + struct pollfd * f; + + f = pfd = _xrealloc(pfd, sizeof(pfd[0]) * regs_used); + + for(p = regs; p < ®s[regs_alloc]; p++) + if(p->fd >= 0) { + f->fd = p->fd; + f->events = 0; + if(p->mask & POLL_IN) + f->events |= poll_in; + if(p->mask & POLL_OUT) + f->events |= poll_out; + if(p->mask & POLL_EXCEPT) + f->events |= poll_except; + f->revents = 0; + p->pfd = f++; + } + assert(f == &pfd[regs_used]); +# endif + +# ifdef USE_SELECT + FD_ZERO(&rset); + FD_ZERO(&wset); + FD_ZERO(&xset); + maxfd = -1; + for(p = regs; p < ®s[regs_alloc]; p++) + if(p->fd >= 0) { + if(p->fd > maxfd) + maxfd = p->fd; + if(p->mask & POLL_IN) + FD_SET(p->fd, &rset); + if(p->mask & POLL_OUT) + FD_SET(p->fd, &wset); + if(p->mask & POLL_EXCEPT) + FD_SET(p->fd, &xset); + } +# endif +} + +int +poll_start_timer(u_int msecs, int repeat, timer_f func, void *arg) +{ + PollTim_t *p; + + /* find unused entry */ + for(p = tims; p < &tims[tims_alloc]; p++) + if(p->func == NULL) + break; + + if(p == &tims[tims_alloc]) { + if(tims_alloc == tims_used) { + size_t newsize = tims_alloc + POLL_REG_GROW; + tims = _xrealloc(tims, sizeof(tims[0]) * newsize); + for(p = &tims[tims_alloc]; p < &tims[newsize]; p++) + p->func = NULL; + p = &tims[tims_alloc]; + tims_alloc = newsize; + } + } + + /* create entry */ + p->msecs = msecs; + p->repeat = repeat; + p->arg = arg; + p->func = func; + p->when = GETMSECS() + msecs; + + tims_used++; + + resort = 1; + + if(rpoll_trace) + fprintf(stderr, "poll_start_timer(%u, %d, %#lx, %#lx)->%u", + msecs, repeat, (u_long)func, (u_long)arg, p - tims); + + return p - tims; +} + +/* + * Here we have to look into the sorted table, whether any entry there points + * into the registration table for the deleted entry. This is needed, + * because a unregistration can occure while we are scanning through the + * table in dispatch(). Do this only, if we are really there - resorting + * will sort out things if we are called from outside the loop. + */ +void +poll_stop_timer(int handle) +{ + u_int i; + + if(rpoll_trace) + fprintf(stderr, "poll_stop_timer(%d)", handle); + + tims[handle].func = NULL; + tims_used--; + + resort = 1; + + if(!in_dispatch) + return; + + for(i = 0; i < tfd_used; i++) + if(tfd[i] == handle) { + tfd[i] = -1; + break; + } +} + +/* + * Squeeze and sort timer table. + * Should perhaps use a custom sort. + */ +static int +tim_cmp(const void *p1, const void *p2) +{ + int t1 = *(const int *)p1; + int t2 = *(const int *)p2; + + return tims[t1].when < tims[t2].when ? -1 + : tims[t1].when > tims[t2].when ? +1 + : 0; +} + +/* + * Reconstruct the tfd-array. This will be an sorted array of indexes + * to the used entries in tims. The next timer to expire will be infront + * of the array. tfd_used is the number of used entries. The array is + * re-allocated if needed. + */ +static void +sort_timers(void) +{ + int *pp; + u_int i; + + if(tims_used > tfd_alloc) { + tfd_alloc = tims_used; + tfd = _xrealloc(tfd, sizeof(int *) * tfd_alloc); + } + + pp = tfd; + + for(i = 0; i < tims_alloc; i++) + if(tims[i].func) + *pp++ = i; + assert(pp - tfd == (ptrdiff_t)tims_used); + + tfd_used = tims_used; + if(tfd_used > 1) + qsort(tfd, tfd_used, sizeof(int), tim_cmp); +} + +/* + * Poll the file descriptors and dispatch to the right function + * If wait is true the poll blocks until somewhat happens. + * Don't use a pointer here, because the called function may cause + * a reallocation! The check for pfd != NULL is required, because + * a sequence of unregister/register could make the wrong callback + * to be called. So we clear pfd in unregister and check here. + */ +void +poll_dispatch(int wait) +{ + u_int i, idx; + int ret; + tval_t now; + int tout; + static u_int last_index; + +# ifdef USE_SELECT + fd_set nrset, nwset, nxset; + struct timeval tv; +# endif + + in_dispatch = 1; + + if(rebuild) { + rebuild = 0; + poll_build(); + } + if(resort) { + resort = 0; + sort_timers(); + } + + /* in wait mode - compute the timeout */ + if(wait) { + if(tfd_used) { + now = GETMSECS(); +# ifdef DEBUG + { + fprintf(stderr, "now=%"QUADFMT"u", now); + for(i = 0; i < tims_used; i++) + fprintf(stderr, "timers[%2d] = %"QUADFMT"d", i, tfd[i]->when - now); + } +# endif + if((tout = tims[tfd[0]].when - now) < 0) + tout = 0; + } else + tout = INFTIM; + } else + tout = 0; + +# ifdef DEBUG + fprintf(stderr, "rpoll -- selecting with tout=%u", tout); +# endif + +# ifdef USE_POLL + ret = poll(pfd, regs_used, tout); +# endif + +# ifdef USE_SELECT + nrset = rset; + nwset = wset; + nxset = xset; + if(tout != INFTIM) { + tv.tv_sec = tout / 1000; + tv.tv_usec = (tout % 1000) * 1000; + } + ret = select(maxfd+1, + SELECT_CAST(&nrset), + SELECT_CAST(&nwset), + SELECT_CAST(&nxset), (tout==INFTIM) ? 0 : &tv); +# endif + + if(ret == -1) { + if(errno == EINTR) + return; + _panic("poll/select: %s", strerror(errno)); + } + + /* dispatch files */ + if(ret > 0) { + for(i = 0; i < regs_alloc; i++) { + idx = rpoll_policy ? ((last_index+i) % regs_alloc) : i; + + assert(idx < regs_alloc); + + if(regs[idx].fd >= 0) { + int mask = 0; + +# ifdef USE_POLL + if(regs[idx].pfd) { + if(regs[idx].pfd->revents & poll_in) + mask |= POLL_IN; + if(regs[idx].pfd->revents & poll_out) + mask |= POLL_OUT; + if(regs[idx].pfd->revents & poll_except) + mask |= POLL_EXCEPT; + } +# endif +# ifdef USE_SELECT + if(FD_ISSET(regs[idx].fd, &nrset)) + mask |= POLL_IN; + if(FD_ISSET(regs[idx].fd, &nwset)) + mask |= POLL_OUT; + if(FD_ISSET(regs[idx].fd, &nxset)) + mask |= POLL_EXCEPT; +# endif + assert(idx < regs_alloc); + + if(mask) { + if(rpoll_trace) + fprintf(stderr, "poll_dispatch() -- " + "file %d/%d", + regs[idx].fd, idx); + (*regs[idx].func)(regs[idx].fd, mask, regs[idx].arg); + } + } + + } + last_index++; + } + + /* dispatch timeouts */ + if(tfd_used) { + now = GETMSECS(); + for(i = 0; i < tfd_used; i++) { + if(tfd[i] < 0) + continue; + if(tims[tfd[i]].when > now) + break; + if(rpoll_trace) + fprintf(stderr, "rpoll_dispatch() -- timeout %d",tfd[i]); + (*tims[tfd[i]].func)(tfd[i], tims[tfd[i]].arg); + if(tfd[i] < 0) + continue; + if(tims[tfd[i]].repeat) + tims[tfd[i]].when = now + tims[tfd[i]].msecs; + else { + tims[tfd[i]].func = NULL; + tims_used--; + tfd[i] = -1; + } + resort = 1; + } + } + in_dispatch = 0; +} + + +# ifdef TESTME +struct timeval start, now; +int t0, t1; + +double elaps(void); +void infunc(int fd, int mask, void *arg); + +double +elaps(void) +{ + gettimeofday(&now, NULL); + + return (double)(10 * now.tv_sec + now.tv_usec / 100000 - 10 * start.tv_sec - start.tv_usec / 100000) + / 10; +} + +void +infunc(int fd, int mask, void *arg) +{ + char buf[1024]; + int ret; + + mask = mask; + arg = arg; + if((ret = read(fd, buf, sizeof(buf))) < 0) + _panic("read: %s", strerror(errno)); + write(1, "stdin:", 6); + write(1, buf, ret); +} + +void tfunc0(int tid, void *arg); +void tfunc1(int tid, void *arg); + +void +tfunc0(int tid, void *arg) +{ + printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg); +} +void +tfunc1(int tid, void *arg) +{ + printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg); +} + +void first(int tid, void *arg); +void second(int tid, void *arg); + +void +second(int tid, void *arg) +{ + printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg); + poll_start_timer(5500, 0, first, "first"); + poll_stop_timer(t1); + t0 = poll_start_timer(1000, 1, tfunc0, "1 second"); +} +void +first(int tid, void *arg) +{ + printf("%4.1f -- %d: %s\n", elaps(), tid, (char *)arg); + poll_start_timer(3700, 0, second, "second"); + poll_stop_timer(t0); + t1 = poll_start_timer(250, 1, tfunc1, "1/4 second"); +} + +int +main(int argc, char *argv[]) +{ + argc = argc; + argv = argv; + gettimeofday(&start, NULL); + poll_register(0, infunc, NULL, POLL_IN); + t0 = poll_start_timer(1000, 1, tfunc0, "1 second"); + poll_start_timer(2500, 0, first, "first"); + + while(1) + poll_dispatch(1); + + return 0; +} +# endif |