From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:35372) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TJpMp-00022X-GY for qemu-devel@nongnu.org; Thu, 04 Oct 2012 13:37:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TJpMo-0003F1-6e for qemu-devel@nongnu.org; Thu, 04 Oct 2012 13:37:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46495) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TJpMn-0003Er-UF for qemu-devel@nongnu.org; Thu, 04 Oct 2012 13:37:46 -0400 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q94HbhLl022176 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 4 Oct 2012 13:37:44 -0400 Date: Thu, 4 Oct 2012 14:38:37 -0300 From: Luiz Capitulino Message-ID: <20121004143837.782ef304@doriath.home> In-Reply-To: <1349275025-5093-5-git-send-email-pbonzini@redhat.com> References: <1349275025-5093-1-git-send-email-pbonzini@redhat.com> <1349275025-5093-5-git-send-email-pbonzini@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 04/18] qemu-sockets: add nonblocking connect for Unix sockets List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org On Wed, 3 Oct 2012 16:36:51 +0200 Paolo Bonzini wrote: This looks like a bug fix, because if is_waitconnect==false unix_connect_opts() shouldn't block. Am I right? Somme comments below. > Signed-off-by: Paolo Bonzini > --- > qemu-char.c | 2 +- > qemu-sockets.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++--------- > qemu_socket.h | 6 ++++- > 3 file modificati, 72 inserzioni(+), 14 rimozioni(-) > > diff --git a/qemu-char.c b/qemu-char.c > index 3cc6cb5..8ebd582 100644 > --- a/qemu-char.c > +++ b/qemu-char.c > @@ -2450,7 +2450,7 @@ static CharDriverState *qemu_chr_open_socket(QemuOpts *opts) > if (is_listen) { > fd = unix_listen_opts(opts, NULL); > } else { > - fd = unix_connect_opts(opts, NULL); > + fd = unix_connect_opts(opts, NULL, NULL, NULL); > } > } else { > if (is_listen) { > diff --git a/qemu-sockets.c b/qemu-sockets.c > index 79c7b66..341ae21 100644 > --- a/qemu-sockets.c > +++ b/qemu-sockets.c > @@ -252,16 +252,19 @@ static void wait_for_connect(void *opaque) > } > > /* try to connect to the next address on the list */ > - while (s->current_addr->ai_next != NULL && s->fd < 0) { > - s->current_addr = s->current_addr->ai_next; > - s->fd = inet_connect_addr(s->current_addr, &in_progress, s); > - /* connect in progress */ > - if (in_progress) { > - return; > + if (s->current_addr) { > + while (s->current_addr->ai_next != NULL && s->fd < 0) { > + s->current_addr = s->current_addr->ai_next; > + s->fd = inet_connect_addr(s->current_addr, &in_progress, s); > + /* connect in progress */ > + if (in_progress) { > + return; > + } > } > + > + freeaddrinfo(s->addr_list); > } > > - freeaddrinfo(s->addr_list); > if (s->callback) { > s->callback(s->fd, s->opaque); > } > @@ -702,32 +705,65 @@ err: > return -1; > } > > -int unix_connect_opts(QemuOpts *opts, Error **errp) > +int unix_connect_opts(QemuOpts *opts, Error **errp, > + NonBlockingConnectHandler *callback, void *opaque) I wonder if having two functions (one non-blocking and another blocking) would be better, as we have some "if (non-blocking) do; else" kind of tests. > { > struct sockaddr_un un; > const char *path = qemu_opt_get(opts, "path"); > - int sock; > + ConnectState *connect_state = NULL; > + int sock, rc; > > if (NULL == path) { > fprintf(stderr, "unix connect: no path specified\n"); > return -1; > } > > + if (callback != NULL) { > + connect_state = g_malloc0(sizeof(*connect_state)); > + connect_state->callback = callback; > + connect_state->opaque = opaque; > + } > + > sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0); > if (sock < 0) { > perror("socket(unix)"); > return -1; > } Leaks connect_state on error, you could delay its allocation. > + if (connect_state != NULL) { > + socket_set_nonblock(sock); > + } > > memset(&un, 0, sizeof(un)); > un.sun_family = AF_UNIX; > snprintf(un.sun_path, sizeof(un.sun_path), "%s", path); > - if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) { > + > + /* connect to peer */ > + do { > + rc = 0; > + if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) { > + rc = -socket_error(); > + } > + } while (rc == -EINTR); Bug fix, woud be nice to comment in the changelog. > + > + if (connect_state != NULL && QEMU_SOCKET_RC_INPROGRESS(rc)) { > + connect_state->fd = sock; > + qemu_set_fd_handler2(sock, NULL, NULL, wait_for_connect, > + connect_state); > + return sock; > + } else { > + /* non blocking socket immediate success, call callback */ > + if (callback != NULL) { > + callback(sock, opaque); > + } > + } Wouldn't this be better written like: if (connect_state) { if (rc == 0) { /* immediate success */ callack(sock, opaque); } else if (QEMU_SOCKET_RC_INPROGRESS(rc)) { connect_state->fd = sock; qemu_set_fd_handler2(...); return sock; } } > + > + if (rc < 0) { > fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno)); > close(sock); > return -1; > } leaks connect_state. > > + g_free(connect_state); > return sock; > } > > @@ -740,7 +776,8 @@ int unix_listen_opts(QemuOpts *opts, Error **errp) > return -1; > } > > -int unix_connect_opts(QemuOpts *opts, Error **errp) > +int unix_connect_opts(QemuOpts *opts, Error **errp, > + NonBlockingConnectHandler *callback, void *opaque) > { > error_setg(errp, "unix sockets are not available on windows"); > errno = ENOTSUP; > @@ -785,7 +822,24 @@ int unix_connect(const char *path, Error **errp) > > opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL); > qemu_opt_set(opts, "path", path); > - sock = unix_connect_opts(opts, errp); > + sock = unix_connect_opts(opts, errp, NULL, NULL); > + qemu_opts_del(opts); > + return sock; > +} > + > + > +int unix_nonblocking_connect(const char *path, > + NonBlockingConnectHandler *callback, > + void *opaque, Error **errp) > +{ > + QemuOpts *opts; > + int sock = -1; > + > + g_assert(callback != NULL); > + > + opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL); > + qemu_opt_set(opts, "path", path); > + sock = unix_connect_opts(opts, errp, callback, opaque); > qemu_opts_del(opts); > return sock; > } > diff --git a/qemu_socket.h b/qemu_socket.h > index ff979b5..89a5feb 100644 > --- a/qemu_socket.h > +++ b/qemu_socket.h > @@ -58,8 +58,12 @@ const char *inet_strfamily(int family); > > int unix_listen_opts(QemuOpts *opts, Error **errp); > int unix_listen(const char *path, char *ostr, int olen, Error **errp); > -int unix_connect_opts(QemuOpts *opts, Error **errp); > +int unix_connect_opts(QemuOpts *opts, Error **errp, > + NonBlockingConnectHandler *callback, void *opaque); > int unix_connect(const char *path, Error **errp); > +int unix_nonblocking_connect(const char *str, > + NonBlockingConnectHandler *callback, > + void *opaque, Error **errp); > > /* Old, ipv4 only bits. Don't use for new code. */ > int parse_host_port(struct sockaddr_in *saddr, const char *str);