iopause: assume poll() is available

Since poll() is available on all platforms we care about, we don't need to
check if it is.

This gets rid of trypoll.c, the last configure-time check that required to be
run on the host (messing with cross). We also get rid of trysysel.c, since
select() was only used as a fallback when poll() isn't avaialble.

Author: 0x5c

configure

@@ -426,25 +426,6 @@ if test -n "$HASDIRENT"; then
 	echo "CPPFLAGS +=	-DHASDIRENT" >> $CONFIG_MK
 fi
 
-#
-# Check for sys/dirent.h.
-#
-printf "Checking for sys/select.h ... "
-if test -n "$HASSYSSEL"; then
-	echo "yes (cached)."
-else
-	if $XCC configure_tests/trysysel.c -o trysysel 2>/dev/null; then
-		echo yes.
-		HASSYSSEL=1
-	else
-		echo no.
-	fi
-	rm -f trysysel
-fi
-if test -n "$HASSYSSEL"; then
-	echo "CPPFLAGS +=	-DHASSYSSEL" >> $CONFIG_MK
-fi
-
 #
 # Check for one argument reboot().
 #
@@ -464,26 +445,6 @@ if test -n "$HASONEARGREBOOT"; then
 	echo "CPPFLAGS +=	-DHASONEARGREBOOT" >> $CONFIG_MK
 fi
 
-#
-# Check for suitable poll().
-# XXX: Very bad, this should not need to run. Do we have alternatives?
-#
-printf "Checking for suitable poll() ... "
-if test -n "$HASGOODPOLL"; then
-	echo "yes (cached)."
-else
-	if $XCC configure_tests/trypoll.c -o trypoll 2>/dev/null && ./trypoll; then
-		echo yes.
-		HASGOODPOLL=1
-	else
-		echo no.
-	fi
-	rm -f trypoll
-fi
-if test -n "$HASGOODPOLL"; then
-	echo "CPPFLAGS +=	-DHASGOODPOLL" >> $CONFIG_MK
-fi
-
 # If --enable-static enabled, build static binaries.
 if [ "$BUILD_STATIC" = "yes" ]; then
 	echo "BUILD_STATIC = -static" >>$CONFIG_MK

configure_tests/trypoll.c

@@ -1,7 +1,6 @@
 /* Public domain. */
 
 #include "taia.h"
-#include "select.h"
 #include "iopause.h"
 
 void iopause(iopause_fd *x,unsigned int len,struct taia *deadline,struct taia *stamp)
@@ -24,55 +23,9 @@ void iopause(iopause_fd *x,unsigned int len,struct taia *deadline,struct taia *s
   for (i = 0;i < len;++i)
     x[i].revents = 0;
 
-#ifdef IOPAUSE_POLL
-
   poll(x,len,millisecs);
   /* XXX: some kernels apparently need x[0] even if len is 0 */
   /* XXX: how to handle EAGAIN? are kernels really this dumb? */
   /* XXX: how to handle EINVAL? when exactly can this happen? */
 
-#else
-{
-
-  struct timeval tv;
-  fd_set rfds;
-  fd_set wfds;
-  int nfds;
-  int fd;
-
-  FD_ZERO(&rfds);
-  FD_ZERO(&wfds);
-
-  nfds = 1;
-  for (i = 0;i < len;++i) {
-    fd = x[i].fd;
-    if (fd < 0) continue;
-    if (fd >= 8 * sizeof(fd_set)) continue; /*XXX*/
-
-    if (fd >= nfds) nfds = fd + 1;
-    if (x[i].events & IOPAUSE_READ) FD_SET(fd,&rfds);
-    if (x[i].events & IOPAUSE_WRITE) FD_SET(fd,&wfds);
-  }
-
-  tv.tv_sec = millisecs / 1000;
-  tv.tv_usec = 1000 * (millisecs % 1000);
-
-  if (select(nfds,&rfds,&wfds,(fd_set *) 0,&tv) <= 0)
-    return;
-    /* XXX: for EBADF, could seek out and destroy the bad descriptor */
-
-  for (i = 0;i < len;++i) {
-    fd = x[i].fd;
-    if (fd < 0) continue;
-    if (fd >= 8 * sizeof(fd_set)) continue; /*XXX*/
-
-    if (x[i].events & IOPAUSE_READ)
-      if (FD_ISSET(fd,&rfds)) x[i].revents |= IOPAUSE_READ;
-    if (x[i].events & IOPAUSE_WRITE)
-      if (FD_ISSET(fd,&wfds)) x[i].revents |= IOPAUSE_WRITE;
-  }
-
-}
-#endif
-
 }

configure_tests/trysysel.c

@@ -3,30 +3,13 @@
 #ifndef IOPAUSE_H
 #define IOPAUSE_H
 
-#ifdef HASGOODPOLL
-
-#define IOPAUSE_POLL
-
 #include <sys/types.h>
 #include <poll.h>
 
 typedef struct pollfd iopause_fd;
 #define IOPAUSE_READ POLLIN
 #define IOPAUSE_WRITE POLLOUT
 
-#else
-
-typedef struct {
-  int fd;
-  short events;
-  short revents;
-} iopause_fd;
-
-#define IOPAUSE_READ 1
-#define IOPAUSE_WRITE 4
-
-#endif
-
 #include "taia.h"
 
 extern void iopause(iopause_fd *,unsigned int,struct taia *,struct taia *);

src/iopause.c

@@ -54,10 +54,6 @@ int main (int argc, const char * const *argv, char * const *envp) {
   int wstat;
   int st;
   iopause_fd x;
-#ifndef IOPAUSE_POLL
-  fd_set rfds;
-  struct timeval t;
-#endif
   char ch;
   int ttyfd;
   struct stat s;
@@ -152,14 +148,7 @@ int main (int argc, const char * const *argv, char * const *envp) {
       sig_unblock(sig_child);
       sig_unblock(sig_cont);
       sig_unblock(sig_int);
-#ifdef IOPAUSE_POLL
       poll(&x, 1, 14000);
-#else
-      t.tv_sec =14; t.tv_usec =0;
-      FD_ZERO(&rfds);
-      FD_SET(x.fd, &rfds);
-      select(x.fd +1, &rfds, (fd_set*)0, (fd_set*)0, &t);
-#endif
       sig_block(sig_cont);
       sig_block(sig_child);
       sig_block(sig_int);