Handle ENOTSOCK properly

git-svn-id: svn://svn.code.sf.net/p/libkqueue/code/trunk@282 fb4e3144-bc1c-4b72-a658-5bcd248dd7f7

ChangeLog

@@ -1,3 +1,13 @@
+2010-08-01  v0.9    r282
+------------------------------------------------------------------------
+
+  * Set kevent.data = 1 for passive sockets that have at least one pending
+    connection.  
+    (Credit to Julien Blache for finding and researching this bug)
+
+  * Fix various compilation errors under Solaris.
+    (Credit to Joakim Johansson for testing and providing patches)
+
 2010-07-21  v0.8    r264
 ------------------------------------------------------------------------
 

config.inc

@@ -1,5 +1,5 @@
 program="libkqueue"
-version="0.9pre"
+version="0.9"
 abi_major="0"
 abi_minor="0"
 abi_version="$abi_major.$abi_minor"

configure

@@ -165,15 +165,15 @@ check_linker() {
     # Appears to be a problem with GCC 4.0 and binutils
     #
     default_ld="$cc"
-    ldflags="-o $program.so.$abi_major.$abi_minor $ldflags"
+    ldflags="-shared -o $program.so.$abi_major.$abi_minor $ldflags"
 
+    # FIXME: port to solaris
     if [ "$target" = "linux" ] ; then
-    ldflags="-shared $ldflags -Wl,-export-dynamic -Wl,-soname,$program.so.$abi_major"
+    ldflags="$ldflags -Wl,-export-dynamic -Wl,-soname,$program.so.$abi_major"
     fi 
 
     if [ "$target" = "solaris" ] ; then
-    default_ld="/usr/ccs/bin/ld"
-    ldflags="-G $ldflags"
+    ldflags="$ldflags"
     fi
 
     finalize ld "$default_ld"

src/common/knote.c

@@ -17,6 +17,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/queue.h>
+#include <sys/socket.h>
+#include <sys/types.h>
 #include <unistd.h>
 
 #include "private.h"
@@ -139,3 +141,31 @@ knote_events_pending(struct filter *filt)
 
     return (res);
 }
+
+/*
+ * Test if a socket is active or passive.
+ */
+int
+knote_get_socket_type(struct knote *kn)
+{
+    socklen_t slen;
+    int i, lsock;
+
+    slen = sizeof(lsock);
+    lsock = 0;
+    i = getsockopt(kn->kev.ident, SOL_SOCKET, SO_ACCEPTCONN, &lsock, &slen);
+    if (i < 0) {
+        switch (errno) {
+            case ENOTSOCK:   /* same as lsock = 0 */
+                return (0);
+                break;
+            default:
+                dbg_printf("getsockopt(3) failed: %s", strerror(errno));
+                return (-1);
+        }
+    } else {
+        if (lsock) 
+            kn->flags |= KNFL_PASSIVE_SOCKET;
+        return (0);
+    }
+}

src/common/private.h

@@ -61,11 +61,17 @@ struct kqueue;
 struct kevent;
 struct evfilt_data;
 
+/* 
+ * Flags used by knote->flags
+ */
+#define KNFL_PASSIVE_SOCKET  (0x01)  /* Socket is in listen(2) mode */
+
 /* TODO: Make this a variable length structure and allow
    each filter to add custom fields at the end.
  */
 struct knote {
     struct kevent     kev;
+    int               flags;       
     union {
         int           pfd;       /* Used by timerfd */
         int           events;    /* Used by socket */
@@ -135,6 +141,7 @@ struct knote *  knote_new(void);
 void        knote_free(struct filter *, struct knote *);
 void        knote_free_all(struct filter *);
 void        knote_insert(struct filter *, struct knote *);
+int         knote_get_socket_type(struct knote *);
 
 /* TODO: these deal with the eventlist, should use a different prefix */
 void        knote_enqueue(struct filter *, struct knote *);

src/linux/socket.c

@@ -127,15 +127,22 @@ evfilt_socket_copyout(struct filter *filt,
             if (ev->events & EPOLLERR)
                 dst->fflags = 1; /* FIXME: Return the actual socket error */
           
-            /* On return, data contains the number of bytes of protocol
-               data available to read.
-             */
-            if (ioctl(dst->ident, 
-                        (dst->filter == EVFILT_READ) ? SIOCINQ : SIOCOUTQ, 
-                        &dst->data) < 0) {
-                /* race condition with socket close, so ignore this error */
-                dbg_puts("ioctl(2) of socket failed");
-                dst->data = 0;
+            if (kn->flags & KNFL_PASSIVE_SOCKET) {
+                /* On return, data contains the length of the 
+                   socket backlog. This is not available under Linux.
+                 */
+                dst->data = 1;
+            } else {
+                /* On return, data contains the number of bytes of protocol
+                   data available to read.
+                 */
+                if (ioctl(dst->ident, 
+                            (dst->filter == EVFILT_READ) ? SIOCINQ : SIOCOUTQ, 
+                            &dst->data) < 0) {
+                    /* race condition with socket close, so ignore this error */
+                    dbg_puts("ioctl(2) of socket failed");
+                    dst->data = 0;
+                }
             }
 
             if (kn->kev.flags & EV_DISPATCH) {
@@ -159,6 +166,9 @@ evfilt_socket_knote_create(struct filter *filt, struct knote *kn)
 {
     struct epoll_event ev;
 
+    if (knote_get_socket_type(kn) < 0)
+        return (-1);
+
     /* Convert the kevent into an epoll_event */
     if (kn->kev.filter == EVFILT_READ)
         kn->data.events = EPOLLIN | EPOLLRDHUP;

src/solaris/socket.c

@@ -91,6 +91,9 @@ evfilt_socket_knote_create(struct filter *filt, struct knote *kn)
 #if TODO
     struct epoll_event ev;
 
+    if (knote_get_socket_type(kn) < 0)
+        return (-1);
+
     /* Convert the kevent into an epoll_event */
     if (kn->kev.filter == EVFILT_READ)
         kn->kn_events = EPOLLIN | EPOLLRDHUP;

test/read.c

@@ -14,6 +14,8 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <arpa/inet.h>
+#include <sys/socket.h>
 #include "common.h"
 
 static int __thread kqfd;
@@ -183,6 +185,46 @@ test_kevent_socket_oneshot(void)
     kevent_socket_drain();
 }
 
+/*
+ * Test if the data field returns 1 when a listen(2) socket has
+ * a pending connection.
+ */
+void
+test_kevent_socket_listen_backlog(void)
+{
+    struct kevent kev;
+    struct sockaddr_in sain;
+    socklen_t sa_len = sizeof(sain);
+    int one = 1;
+    const short port = 14973;
+    int clnt, srvr;
+
+    /* Create a passive socket */
+    sain.sin_family = AF_INET;
+    sain.sin_port = htons(port);
+    if ((srvr = socket(PF_INET, SOCK_STREAM, 0)) < 0) abort();
+    if (setsockopt(srvr, SOL_SOCKET, SO_REUSEADDR, 
+                (char *) &one, sizeof(one)) != 0) abort();
+    if (bind(srvr, (struct sockaddr *) &sain, sa_len) < 0) abort();
+    if (listen(srvr, 100) < 0) abort();
+
+    /* Watch for events on the socket */
+    test_no_kevents(kqfd);
+    kevent_add(kqfd, &kev, srvr, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, NULL);
+    test_no_kevents(kqfd);
+
+    /* Simulate a client connecting to the server */
+    sain.sin_family = AF_INET;
+    sain.sin_port = htons(port);
+    sain.sin_addr.s_addr = inet_addr("127.0.0.1");
+    if ((clnt = socket(AF_INET, SOCK_STREAM, 0)) < 0) abort();
+    if (connect(clnt, (struct sockaddr *) &sain, sa_len) < 0) abort();
+
+    /* Verify that data=1 */
+    kev.data = 1;
+    kevent_cmp(&kev, kevent_get(kqfd));
+    test_no_kevents(kqfd);
+}
 
 #if HAVE_EV_DISPATCH
 void
@@ -284,6 +326,7 @@ test_evfilt_read(int _kqfd)
 #if HAVE_EV_DISPATCH
     test(kevent_socket_dispatch);
 #endif
+    test(kevent_socket_listen_backlog);
     test(kevent_socket_eof);
     close(sockfd[0]);
     close(sockfd[1]);

www/index.html

@@ -119,6 +119,9 @@ When an EVFILT_SIGNAL event is generated, the <code>data</code> field
 is set to 1 regardless of how many times the signal was received by the process.
 </li>
 
+<li>
+When an EVFILT_READ event occurs on a listening socket, the   <code>data</code> field is set to 1 regardless of how many pending connections are available.
+
 <!--
 <li>
 The EVFILT_PROC filter only supports the NOTE_EXIT flag, and the <code>ident</code> field must contain the PID of a child of the current process. This filter is only suitable as an event-driven replacement for the <code>wait(2)</code> family of system calls.