Fixes oscarlab/graphene#239 (shim_do_epoll_wait ignores user-supplied timeout)

Better unit test to test shim_do_epoll_wait

LibOS/shim/src/sys/shim_epoll.c

@@ -321,8 +321,11 @@ retry:
 
     unlock(epoll_hdl->lock);
 
+    if (timeout < 0)
+        timeout = NO_TIMEOUT;
+
     PAL_HANDLE polled = DkObjectsWaitAny(nread ? npals + 1 : npals, pal_handles,
-                                         nread ? NO_TIMEOUT : 0);
+                                         nread ? timeout : 0);
 
     lock(epoll_hdl->lock);
 

LibOS/shim/test/regression/80_epoll_wait_timeout.py

@@ -0,0 +1,15 @@
+#!/usr/bin/python
+
+import os, sys, mmap
+from regression import Regression
+
+loader = sys.argv[1]
+
+regression = Regression(loader, "epoll_wait_timeout", None, 50000)
+
+regression.add_check(name="epoll_wait timeout",
+    args = ['8000'],
+    check=lambda res: "epoll_wait test passed" in res[0].out)
+
+rv = regression.run_checks()
+if rv: sys.exit(rv)

LibOS/shim/test/regression/epoll_wait_timeout.c

@@ -0,0 +1,126 @@
+/* -*- mode:c; c-file-style:"k&r"; c-basic-offset: 4; tab-width:4; indent-tabs-mode:nil; mode:auto-fill; fill-column:78; -*- */
+/* vim: set ts=4 sw=4 et tw=78 fo=cqt wm=0: */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/epoll.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+
+/* On success, a file descriptor for the new socket is returned.
+ * On error, -1 is returned. */
+static int create_and_bind (char *port) {
+    struct addrinfo hints;
+    struct addrinfo *result, *rp;
+    int s, sfd;
+
+    memset (&hints, 0, sizeof (struct addrinfo));
+    hints.ai_family = AF_UNSPEC;     /* Return IPv4 and IPv6 choices */
+    hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */
+    hints.ai_flags = AI_PASSIVE;     /* All interfaces */
+
+    s = getaddrinfo (NULL, port, &hints, &result);
+    if (s != 0) {
+        fprintf (stderr, "getaddrinfo: %s\n", gai_strerror (s));
+        return -1;
+    }
+
+    for (rp = result; rp != NULL; rp = rp->ai_next) {
+        sfd = socket (rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+        if (sfd == -1)
+            continue;
+
+        s = bind (sfd, rp->ai_addr, rp->ai_addrlen);
+        if (s == 0) {
+            /* We managed to bind successfully! */
+            break;
+        }
+
+        close (sfd);
+    }
+
+    if (rp == NULL) {
+        fprintf (stderr, "Could not bind\n");
+        return -1;
+    }
+
+    freeaddrinfo (result);
+    return sfd;
+}
+
+/* On success, 0 is returned. On error, -1 is returned. */
+static int make_socket_non_blocking (int sfd) {
+    int flags, s;
+
+    flags = fcntl (sfd, F_GETFL, 0);
+    if (flags == -1) {
+        perror ("fcntl");
+        return -1;
+    }
+
+    flags |= O_NONBLOCK;
+    s = fcntl (sfd, F_SETFL, flags);
+    if (s == -1) {
+        perror ("fcntl");
+        return -1;
+    }
+
+    return 0;
+}
+
+#define MAXEVENTS 64
+
+int main (int argc, char *argv[]) {
+    int sfd, s, n;
+    int efd;
+    struct epoll_event event;
+    struct epoll_event *events;
+
+    if (argc != 2) {
+        perror("please specify port");
+        return 1;
+    }
+
+    sfd = create_and_bind(argv[1]);
+    if (sfd == -1)
+        return 1;
+
+    s = make_socket_non_blocking(sfd);
+    if (s == -1)
+        return 1;
+
+    s = listen(sfd, SOMAXCONN);
+    if (s == -1) {
+        perror ("listen");
+        return 1;
+    }
+
+    efd = epoll_create1(0);
+    if (efd == -1) {
+        perror ("epoll_create");
+        return 1;
+    }
+
+    event.data.fd = sfd;
+    event.events = EPOLLIN | EPOLLET;
+    s = epoll_ctl (efd, EPOLL_CTL_ADD, sfd, &event);
+    if (s == -1) {
+        perror ("epoll_ctl");
+        return 1;
+    }
+
+    events = calloc (MAXEVENTS, sizeof event);
+
+    /* epoll_wait with 1 second timeout */
+    n = epoll_wait (efd, events, MAXEVENTS, 1000);
+
+    printf("epoll_wait test passed\n");
+    free (events);
+    close (sfd);
+    return 0;
+}