- (dtucker) [atomicio.c configure.ac openbsd-compat/Makefile.in

   openbsd-compat/bsd-poll.{c,h} openbsd-compat/openbsd-compat.h]
   Add an implementation of poll() built on top of select(2).  Code from
   OpenNTPD with changes suggested by djm.  ok djm@

1 files changed, 117 insertions, 0 deletions

diff --git a/openbsd-compat/bsd-poll.c b/openbsd-compat/bsd-poll.c
new file mode 100644
index 000000000..836882eea
--- /dev/null
+++ b/openbsd-compat/bsd-poll.c
@@ -0,0 +1,117 @@
+/* $Id: bsd-poll.c,v 1.1 2007/06/25 12:15:13 dtucker Exp $ */
+
+/*
+ * Copyright (c) 2004, 2005, 2007 Darren Tucker (dtucker at zip com au).
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+#if !defined(HAVE_POLL) && defined(HAVE_SELECT)
+
+#ifdef HAVE_SYS_SELECT_H
+# include <sys/select.h>
+#endif
+
+#include <errno.h>
+#include "bsd-poll.h"
+
+/*
+ * A minimal implementation of poll(2), built on top of select(2).
+ *
+ * Only supports POLLIN and POLLOUT flags in pfd.events, and POLLIN, POLLOUT
+ * and POLLERR flags in revents.
+ *
+ * Supports pfd.fd = -1 meaning "unused" although it's not standard.
+ */
+
+int
+poll(struct pollfd *fds, nfds_t nfds, int timeout)
+{
+        nfds_t i;
+        int saved_errno, ret, fd, maxfd = 0;
+        fd_set *readfds = NULL, *writefds = NULL, *exceptfds = NULL;
+        size_t nmemb;
+        struct timeval tv, *tvp = NULL;
+
+        for (i = 0; i < nfds; i++) {
+                if (fd >= FD_SETSIZE) {
+                        errno = EINVAL;
+                        return -1;
+                }
+                maxfd = MAX(maxfd, fds[i].fd);
+        }
+
+        nmemb = howmany(maxfd + 1 , NFDBITS);
+        if ((readfds = calloc(nmemb, sizeof(fd_mask))) == NULL ||
+            (writefds = calloc(nmemb, sizeof(fd_mask))) == NULL ||
+            (exceptfds = calloc(nmemb, sizeof(fd_mask))) == NULL) {
+                saved_errno = ENOMEM;
+                ret = -1;
+                goto out;
+        }
+
+        /* populate event bit vectors for the events we're interested in */
+        for (i = 0; i < nfds; i++) {
+                fd = fds[i].fd;
+                if (fd == -1)
+                        continue;
+                if (fds[i].events & POLLIN) {
+                        FD_SET(fd, readfds);
+                        FD_SET(fd, exceptfds);
+                }
+                if (fds[i].events & POLLOUT) {
+                        FD_SET(fd, writefds);
+                        FD_SET(fd, exceptfds);
+                }
+        }
+
+        /* poll timeout is msec, select is timeval (sec + usec) */
+        if (timeout >= 0) {
+                tv.tv_sec = timeout / 1000;
+                tv.tv_usec = (timeout % 1000) * 1000;
+                tvp = &tv;
+        }
+
+        ret = select(maxfd + 1, readfds, writefds, exceptfds, tvp);
+        saved_errno = errno;
+
+        /* scan through select results and set poll() flags */
+        for (i = 0; i < nfds; i++) {
+                fd = fds[i].fd;
+                fds[i].revents = 0;
+                if (fd == -1)
+                        continue;
+                if (FD_ISSET(fd, readfds)) {
+                        fds[i].revents |= POLLIN;
+                }
+                if (FD_ISSET(fd, writefds)) {
+                        fds[i].revents |= POLLOUT;
+                }
+                if (FD_ISSET(fd, exceptfds)) {
+                        fds[i].revents |= POLLERR;
+                }
+        }
+
+out:
+        if (readfds != NULL)
+                free(readfds);
+        if (writefds != NULL)
+                free(writefds);
+        if (exceptfds != NULL)
+                free(exceptfds);
+        if (ret == -1)
+                errno = saved_errno;
+        return ret;
+}
+#endif