[Qemu-devel] [PATCH v8 0/4] Improve error reporting

[Qemu-devel] [PATCH v8 0/4] Improve error reporting

[Mao Zhongyi]

v8:
* PATCH 02 & 04
  -resetting the error message for the user to read.   [Markus Armbruster]
  
v7:
* PATCH 01
  -fix the error message.    [Daniel P. Berrange]
  -adjust the Indentation problem.    [Eric Blake]
* PATCH 03
  -print a generic message when gethostbyname() failed in parse_host_port(),
   drop the misleading ": unkonwn host" part.    [Markus Armbruster]

v6:
* PATCH 02
  -rename the subject
  -drop the "qemu: error: " prefix.
  -correct inappropriate error information settings.
* PATCH 03,04
  -correct inappropriate error information settings.    [Markus Armbruster]

v5:
* PATCH 01 make the commit message more exact about the actual function.    [Markus Armbruster]
* PATCH 02, 03, 04 still retains the original function, but specific
           content and order of each patch has been adjusted substantially, 
           so that ensure each patch is a completed fix.    [Markus Armbruster]

v4: 
* PATCH 01 is redoing previous patch 1, replace the fprintf() with error_report()
		     in the 'default' case of net_socket_fd_init() [Markus Armbruster]

v3:
* PATCH 01 is suggested by Markus and Daniel that removes the dubious 'default' case
           in the net_socket_fd_init(). Jason agreed.
* PATCH 02 is redoing previous patch 4.
* PATCH 04 is redoing previous patch 2, improves sort of error messages. 

v2:
* PATCH 02 reworking of patch 2 following Markus's suggestion that convert error_report()
           in the function called by net_socket_*_init() to Error. Also add many error 
           handling information.
* PATCH 03 net_socket_mcast_create(), net_socket_fd_init_dgram() and net_socket_fd_init() 
           use the function such as fprintf, perror to report an error message. Convert it 
           to Error.
* PATCH 04 parse_host_port() may fail without reporting an error. Now, fix it to set an
           error when it fails.

Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: berrange@redhat.com
Cc: kraxel@redhat.com
Cc: pbonzini@redhat.com
Cc: eblake@redhat.com

Mao Zhongyi (4):
  net/socket: Don't treat odd socket type as SOCK_STREAM
  net/socket: Convert several helper functions to Error
  net/net: Convert parse_host_port() to Error
  net/socket: Improve -net socket error reporting

 include/qemu/sockets.h |   3 +-
 net/net.c              |  22 +++++--
 net/socket.c           | 153 ++++++++++++++++++++++++++++---------------------
 3 files changed, 106 insertions(+), 72 deletions(-)

-- 
2.9.4

[Qemu-devel] [PATCH v8 1/4] net/socket: Don't treat odd socket type as SOCK_STREAM

[Mao Zhongyi]

In net_socket_fd_init(), the 'default' case is odd: it warns,
then continues as if the socket type was SOCK_STREAM. The
comment explains "this could be a eg. a pty", but that makes
no sense. If @fd really was a pty, getsockopt() would fail
with ENOTSOCK. If @fd was a socket, but neither SOCK_DGRAM nor
SOCK_STREAM. It should not be treated as if it was SOCK_STREAM.

Turn this case into an Error. If there is a genuine reason to
support something like SOCK_RAW, it should be explicitly
handled.

Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: berrange@redhat.com
Cc: armbru@redhat.com
Cc: eblake@redhat.com
Suggested-by: Markus Armbruster <armbru@redhat.com>
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
 net/socket.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index dcae1ae..7d05e70 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -449,9 +449,9 @@ static NetSocketState *net_socket_fd_init(NetClientState *peer,
     case SOCK_STREAM:
         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
     default:
-        /* who knows ... this could be a eg. a pty, do warn and continue as stream */
-        fprintf(stderr, "qemu: warning: socket type=%d for fd=%d is not SOCK_DGRAM or SOCK_STREAM\n", so_type, fd);
-        return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
+        error_report("socket type=%d for fd=%d must be either"
+                     " SOCK_DGRAM or SOCK_STREAM", so_type, fd);
+        closesocket(fd);
     }
     return NULL;
 }
-- 
2.9.4

[Qemu-devel] [PATCH v8 2/4] net/socket: Convert several helper functions to Error

[Mao Zhongyi]

Currently, net_socket_mcast_create(), net_socket_fd_init_dgram() and
net_socket_fd_init() use the function such as fprintf(), perror() to
report an error message.

Now, convert these functions to Error.

Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: berrange@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
---
 net/socket.c | 80 ++++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 48 insertions(+), 32 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index 7d05e70..3dd4459 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -209,7 +209,9 @@ static void net_socket_send_dgram(void *opaque)
     }
 }
 
-static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr *localaddr)
+static int net_socket_mcast_create(struct sockaddr_in *mcastaddr,
+                                   struct in_addr *localaddr,
+                                   Error **errp)
 {
     struct ip_mreq imr;
     int fd;
@@ -221,16 +223,16 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
 #endif
 
     if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
-        fprintf(stderr, "qemu: error: specified mcastaddr \"%s\" (0x%08x) "
-                "does not contain a multicast address\n",
-                inet_ntoa(mcastaddr->sin_addr),
-                (int)ntohl(mcastaddr->sin_addr.s_addr));
+        error_setg(errp, "specified mcastaddr %s (0x%08x) "
+                   "does not contain a multicast address",
+                   inet_ntoa(mcastaddr->sin_addr),
+                   (int)ntohl(mcastaddr->sin_addr.s_addr));
         return -1;
-
     }
+
     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
     if (fd < 0) {
-        perror("socket(PF_INET, SOCK_DGRAM)");
+        error_setg_errno(errp, errno, "can't create datagram socket");
         return -1;
     }
 
@@ -242,13 +244,15 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     val = 1;
     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
     if (ret < 0) {
-        perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
+        error_setg_errno(errp, errno,
+                         "can't set socket option SO_REUSEADDR");
         goto fail;
     }
 
     ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
     if (ret < 0) {
-        perror("bind");
+        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                         inet_ntoa(mcastaddr->sin_addr));
         goto fail;
     }
 
@@ -263,7 +267,9 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
                           &imr, sizeof(struct ip_mreq));
     if (ret < 0) {
-        perror("setsockopt(IP_ADD_MEMBERSHIP)");
+        error_setg_errno(errp, errno,
+                         "can't add socket to multicast group %s",
+                         inet_ntoa(imr.imr_multiaddr));
         goto fail;
     }
 
@@ -272,7 +278,8 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
                           &loop, sizeof(loop));
     if (ret < 0) {
-        perror("setsockopt(SOL_IP, IP_MULTICAST_LOOP)");
+        error_setg_errno(errp, errno,
+                         "can't force multicast message to loopback");
         goto fail;
     }
 
@@ -281,7 +288,8 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
         ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
                               localaddr, sizeof(*localaddr));
         if (ret < 0) {
-            perror("setsockopt(IP_MULTICAST_IF)");
+            error_setg_errno(errp, errno,
+                             "can't set the default network send interface");
             goto fail;
         }
     }
@@ -320,7 +328,8 @@ static NetClientInfo net_dgram_socket_info = {
 static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
                                                 const char *model,
                                                 const char *name,
-                                                int fd, int is_connected)
+                                                int fd, int is_connected,
+                                                Error **errp)
 {
     struct sockaddr_in saddr;
     int newfd;
@@ -337,14 +346,12 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
         if (getsockname(fd, (struct sockaddr *) &saddr, &saddr_len) == 0) {
             /* must be bound */
             if (saddr.sin_addr.s_addr == 0) {
-                fprintf(stderr, "qemu: error: init_dgram: fd=%d unbound, "
-                        "cannot setup multicast dst addr\n", fd);
+                error_setg(errp, "can't setup multicast destination address");
                 goto err;
             }
             /* clone dgram socket */
-            newfd = net_socket_mcast_create(&saddr, NULL);
+            newfd = net_socket_mcast_create(&saddr, NULL, errp);
             if (newfd < 0) {
-                /* error already reported by net_socket_mcast_create() */
                 goto err;
             }
             /* clone newfd to fd, close newfd */
@@ -352,9 +359,7 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
             close(newfd);
 
         } else {
-            fprintf(stderr,
-                    "qemu: error: init_dgram: fd=%d failed getsockname(): %s\n",
-                    fd, strerror(errno));
+            error_setg_errno(errp, errno, "can't get socket name");
             goto err;
         }
     }
@@ -432,20 +437,21 @@ static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 
 static NetSocketState *net_socket_fd_init(NetClientState *peer,
                                           const char *model, const char *name,
-                                          int fd, int is_connected)
+                                          int fd, int is_connected,
+                                          Error **errp)
 {
     int so_type = -1, optlen=sizeof(so_type);
 
     if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
         (socklen_t *)&optlen)< 0) {
-        fprintf(stderr, "qemu: error: getsockopt(SO_TYPE) for fd=%d failed\n",
-                fd);
+        error_setg(errp, "can't get socket option SO_TYPE");
         closesocket(fd);
         return NULL;
     }
     switch(so_type) {
     case SOCK_DGRAM:
-        return net_socket_fd_init_dgram(peer, model, name, fd, is_connected);
+        return net_socket_fd_init_dgram(peer, model, name, fd, is_connected,
+                                        errp);
     case SOCK_STREAM:
         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
     default:
@@ -536,6 +542,7 @@ static int net_socket_connect_init(NetClientState *peer,
     NetSocketState *s;
     int fd, connected, ret;
     struct sockaddr_in saddr;
+    Error *err = NULL;
 
     if (parse_host_port(&saddr, host_str) < 0)
         return -1;
@@ -567,9 +574,11 @@ static int net_socket_connect_init(NetClientState *peer,
             break;
         }
     }
-    s = net_socket_fd_init(peer, model, name, fd, connected);
-    if (!s)
+    s = net_socket_fd_init(peer, model, name, fd, connected, &err);
+    if (!s) {
+        error_report_err(err);
         return -1;
+    }
     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
              "socket: connect to %s:%d",
              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
@@ -586,6 +595,7 @@ static int net_socket_mcast_init(NetClientState *peer,
     int fd;
     struct sockaddr_in saddr;
     struct in_addr localaddr, *param_localaddr;
+    Error *err = NULL;
 
     if (parse_host_port(&saddr, host_str) < 0)
         return -1;
@@ -598,13 +608,17 @@ static int net_socket_mcast_init(NetClientState *peer,
         param_localaddr = NULL;
     }
 
-    fd = net_socket_mcast_create(&saddr, param_localaddr);
-    if (fd < 0)
+    fd = net_socket_mcast_create(&saddr, param_localaddr, &err);
+    if (fd < 0) {
+        error_report_err(err);
         return -1;
+    }
 
-    s = net_socket_fd_init(peer, model, name, fd, 0);
-    if (!s)
+    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
+    if (!s) {
+        error_report_err(err);
         return -1;
+    }
 
     s->dgram_dst = saddr;
 
@@ -624,6 +638,7 @@ static int net_socket_udp_init(NetClientState *peer,
     NetSocketState *s;
     int fd, ret;
     struct sockaddr_in laddr, raddr;
+    Error *err = NULL;
 
     if (parse_host_port(&laddr, lhost) < 0) {
         return -1;
@@ -652,8 +667,9 @@ static int net_socket_udp_init(NetClientState *peer,
     }
     qemu_set_nonblock(fd);
 
-    s = net_socket_fd_init(peer, model, name, fd, 0);
+    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
     if (!s) {
+        error_report_err(err);
         return -1;
     }
 
@@ -696,7 +712,7 @@ int net_init_socket(const Netdev *netdev, const char *name,
             return -1;
         }
         qemu_set_nonblock(fd);
-        if (!net_socket_fd_init(peer, "socket", name, fd, 1)) {
+        if (!net_socket_fd_init(peer, "socket", name, fd, 1, errp)) {
             return -1;
         }
         return 0;
-- 
2.9.4

[Qemu-devel] [PATCH v8 3/4] net/net: Convert parse_host_port() to Error

[Mao Zhongyi]

Cc: berrange@redhat.com
Cc: kraxel@redhat.com
Cc: pbonzini@redhat.com
Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: eblake@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
 include/qemu/sockets.h |  3 ++-
 net/net.c              | 22 +++++++++++++++++-----
 net/socket.c           | 19 ++++++++++++++-----
 3 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h
index 5c326db..78e2b30 100644
--- a/include/qemu/sockets.h
+++ b/include/qemu/sockets.h
@@ -53,7 +53,8 @@ void socket_listen_cleanup(int fd, Error **errp);
 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp);
 
 /* Old, ipv4 only bits.  Don't use for new code. */
-int parse_host_port(struct sockaddr_in *saddr, const char *str);
+int parse_host_port(struct sockaddr_in *saddr, const char *str,
+                    Error **errp);
 int socket_init(void);
 
 /**
diff --git a/net/net.c b/net/net.c
index 6235aab..77b6deb 100644
--- a/net/net.c
+++ b/net/net.c
@@ -100,7 +100,8 @@ static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
     return 0;
 }
 
-int parse_host_port(struct sockaddr_in *saddr, const char *str)
+int parse_host_port(struct sockaddr_in *saddr, const char *str,
+                    Error **errp)
 {
     char buf[512];
     struct hostent *he;
@@ -108,24 +109,35 @@ int parse_host_port(struct sockaddr_in *saddr, const char *str)
     int port;
 
     p = str;
-    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
+    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
+        error_setg(errp, "host address '%s' doesn't contain ':' "
+                   "separating host from port", str);
         return -1;
+    }
     saddr->sin_family = AF_INET;
     if (buf[0] == '\0') {
         saddr->sin_addr.s_addr = 0;
     } else {
         if (qemu_isdigit(buf[0])) {
-            if (!inet_aton(buf, &saddr->sin_addr))
+            if (!inet_aton(buf, &saddr->sin_addr)) {
+                error_setg(errp, "host address '%s' is not a valid "
+                           "IPv4 address", buf);
                 return -1;
+            }
         } else {
-            if ((he = gethostbyname(buf)) == NULL)
+            he = gethostbyname(buf);
+            if (he == NULL) {
+                error_setg(errp, "can't resolve host address '%s'", buf);
                 return - 1;
+            }
             saddr->sin_addr = *(struct in_addr *)he->h_addr;
         }
     }
     port = strtol(p, (char **)&r, 0);
-    if (r == p)
+    if (r == p) {
+        error_setg(errp, "port number '%s' is invalid", p);
         return -1;
+    }
     saddr->sin_port = htons(port);
     return 0;
 }
diff --git a/net/socket.c b/net/socket.c
index 3dd4459..1d4c515 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -497,9 +497,12 @@ static int net_socket_listen_init(NetClientState *peer,
     NetSocketState *s;
     struct sockaddr_in saddr;
     int fd, ret;
+    Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str) < 0)
+    if (parse_host_port(&saddr, host_str, &err) < 0) {
+        error_report_err(err);
         return -1;
+    }
 
     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
     if (fd < 0) {
@@ -544,8 +547,10 @@ static int net_socket_connect_init(NetClientState *peer,
     struct sockaddr_in saddr;
     Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str) < 0)
+    if (parse_host_port(&saddr, host_str, &err) < 0) {
+        error_report_err(err);
         return -1;
+    }
 
     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
     if (fd < 0) {
@@ -597,8 +602,10 @@ static int net_socket_mcast_init(NetClientState *peer,
     struct in_addr localaddr, *param_localaddr;
     Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str) < 0)
+    if (parse_host_port(&saddr, host_str, &err) < 0) {
+        error_report_err(err);
         return -1;
+    }
 
     if (localaddr_str != NULL) {
         if (inet_aton(localaddr_str, &localaddr) == 0)
@@ -640,11 +647,13 @@ static int net_socket_udp_init(NetClientState *peer,
     struct sockaddr_in laddr, raddr;
     Error *err = NULL;
 
-    if (parse_host_port(&laddr, lhost) < 0) {
+    if (parse_host_port(&laddr, lhost, &err) < 0) {
+        error_report_err(err);
         return -1;
     }
 
-    if (parse_host_port(&raddr, rhost) < 0) {
+    if (parse_host_port(&raddr, rhost, &err) < 0) {
+        error_report_err(err);
         return -1;
     }
 
-- 
2.9.4

[Qemu-devel] [PATCH v8 4/4] net/socket: Improve -net socket error reporting

[Mao Zhongyi]

When -net socket fails, it first reports a specific error, then
a generic one, like this:

    $ qemu-system-x86_64 -net socket,
    qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required
    qemu-system-x86_64: -net socket: Device 'socket' could not be initialized

Convert net_socket_*_init() to Error to get rid of the superfluous second
error message. After the patch, the effect like this:

    $ qemu-system-x86_64 -net socket,
    qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required

At the same time, add many explicit error handling message when it fails.

Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: berrange@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
---
 net/socket.c | 92 +++++++++++++++++++++++++++++-------------------------------
 1 file changed, 44 insertions(+), 48 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index 1d4c515..ca1878f 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -491,22 +491,21 @@ static void net_socket_accept(void *opaque)
 static int net_socket_listen_init(NetClientState *peer,
                                   const char *model,
                                   const char *name,
-                                  const char *host_str)
+                                  const char *host_str,
+                                  Error **errp)
 {
     NetClientState *nc;
     NetSocketState *s;
     struct sockaddr_in saddr;
     int fd, ret;
-    Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str, &err) < 0) {
-        error_report_err(err);
+    if (parse_host_port(&saddr, host_str, errp) < 0) {
         return -1;
     }
 
     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
     if (fd < 0) {
-        perror("socket");
+        error_setg_errno(errp, errno, "can't create stream socket");
         return -1;
     }
     qemu_set_nonblock(fd);
@@ -515,13 +514,14 @@ static int net_socket_listen_init(NetClientState *peer,
 
     ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
     if (ret < 0) {
-        perror("bind");
+        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                         inet_ntoa(saddr.sin_addr));
         closesocket(fd);
         return -1;
     }
     ret = listen(fd, 0);
     if (ret < 0) {
-        perror("listen");
+        error_setg_errno(errp, errno, "can't listen on socket");
         closesocket(fd);
         return -1;
     }
@@ -540,21 +540,20 @@ static int net_socket_listen_init(NetClientState *peer,
 static int net_socket_connect_init(NetClientState *peer,
                                    const char *model,
                                    const char *name,
-                                   const char *host_str)
+                                   const char *host_str,
+                                   Error **errp)
 {
     NetSocketState *s;
     int fd, connected, ret;
     struct sockaddr_in saddr;
-    Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str, &err) < 0) {
-        error_report_err(err);
+    if (parse_host_port(&saddr, host_str, errp) < 0) {
         return -1;
     }
 
     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
     if (fd < 0) {
-        perror("socket");
+        error_setg_errno(errp, errno, "can't create stream socket");
         return -1;
     }
     qemu_set_nonblock(fd);
@@ -570,7 +569,7 @@ static int net_socket_connect_init(NetClientState *peer,
                        errno == EINVAL) {
                 break;
             } else {
-                perror("connect");
+                error_setg_errno(errp, errno, "can't connect socket");
                 closesocket(fd);
                 return -1;
             }
@@ -579,9 +578,8 @@ static int net_socket_connect_init(NetClientState *peer,
             break;
         }
     }
-    s = net_socket_fd_init(peer, model, name, fd, connected, &err);
+    s = net_socket_fd_init(peer, model, name, fd, connected, errp);
     if (!s) {
-        error_report_err(err);
         return -1;
     }
     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
@@ -594,36 +592,36 @@ static int net_socket_mcast_init(NetClientState *peer,
                                  const char *model,
                                  const char *name,
                                  const char *host_str,
-                                 const char *localaddr_str)
+                                 const char *localaddr_str,
+                                 Error **errp)
 {
     NetSocketState *s;
     int fd;
     struct sockaddr_in saddr;
     struct in_addr localaddr, *param_localaddr;
-    Error *err = NULL;
 
-    if (parse_host_port(&saddr, host_str, &err) < 0) {
-        error_report_err(err);
+    if (parse_host_port(&saddr, host_str, errp) < 0) {
         return -1;
     }
 
     if (localaddr_str != NULL) {
-        if (inet_aton(localaddr_str, &localaddr) == 0)
+        if (inet_aton(localaddr_str, &localaddr) == 0) {
+            error_setg(errp, "localaddr '%s' is not a valid IPv4 address",
+                       localaddr_str);
             return -1;
+        }
         param_localaddr = &localaddr;
     } else {
         param_localaddr = NULL;
     }
 
-    fd = net_socket_mcast_create(&saddr, param_localaddr, &err);
+    fd = net_socket_mcast_create(&saddr, param_localaddr, errp);
     if (fd < 0) {
-        error_report_err(err);
         return -1;
     }
 
-    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
+    s = net_socket_fd_init(peer, model, name, fd, 0, errp);
     if (!s) {
-        error_report_err(err);
         return -1;
     }
 
@@ -640,45 +638,45 @@ static int net_socket_udp_init(NetClientState *peer,
                                  const char *model,
                                  const char *name,
                                  const char *rhost,
-                                 const char *lhost)
+                                 const char *lhost,
+                                 Error **errp)
 {
     NetSocketState *s;
     int fd, ret;
     struct sockaddr_in laddr, raddr;
-    Error *err = NULL;
 
-    if (parse_host_port(&laddr, lhost, &err) < 0) {
-        error_report_err(err);
+    if (parse_host_port(&laddr, lhost, errp) < 0) {
         return -1;
     }
 
-    if (parse_host_port(&raddr, rhost, &err) < 0) {
-        error_report_err(err);
+    if (parse_host_port(&raddr, rhost, errp) < 0) {
         return -1;
     }
 
     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
     if (fd < 0) {
-        perror("socket(PF_INET, SOCK_DGRAM)");
+        error_setg_errno(errp, errno, "can't create datagram socket");
         return -1;
     }
 
     ret = socket_set_fast_reuse(fd);
     if (ret < 0) {
+        error_setg_errno(errp, errno,
+                         "can't set socket option SO_REUSEADDR");
         closesocket(fd);
         return -1;
     }
     ret = bind(fd, (struct sockaddr *)&laddr, sizeof(laddr));
     if (ret < 0) {
-        perror("bind");
+        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                         inet_ntoa(laddr.sin_addr));
         closesocket(fd);
         return -1;
     }
     qemu_set_nonblock(fd);
 
-    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
+    s = net_socket_fd_init(peer, model, name, fd, 0, errp);
     if (!s) {
-        error_report_err(err);
         return -1;
     }
 
@@ -693,8 +691,6 @@ static int net_socket_udp_init(NetClientState *peer,
 int net_init_socket(const Netdev *netdev, const char *name,
                     NetClientState *peer, Error **errp)
 {
-    /* FIXME error_setg(errp, ...) on failure */
-    Error *err = NULL;
     const NetdevSocketOptions *sock;
 
     assert(netdev->type == NET_CLIENT_DRIVER_SOCKET);
@@ -702,22 +698,21 @@ int net_init_socket(const Netdev *netdev, const char *name,
 
     if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
         sock->has_udp != 1) {
-        error_report("exactly one of fd=, listen=, connect=, mcast= or udp="
-                     " is required");
+        error_setg(errp, "exactly one of fd=, listen=, connect=, mcast= or udp="
+                   " is required");
         return -1;
     }
 
     if (sock->has_localaddr && !sock->has_mcast && !sock->has_udp) {
-        error_report("localaddr= is only valid with mcast= or udp=");
+        error_setg(errp, "localaddr= is only valid with mcast= or udp=");
         return -1;
     }
 
     if (sock->has_fd) {
         int fd;
 
-        fd = monitor_fd_param(cur_mon, sock->fd, &err);
+        fd = monitor_fd_param(cur_mon, sock->fd, errp);
         if (fd == -1) {
-            error_report_err(err);
             return -1;
         }
         qemu_set_nonblock(fd);
@@ -728,15 +723,16 @@ int net_init_socket(const Netdev *netdev, const char *name,
     }
 
     if (sock->has_listen) {
-        if (net_socket_listen_init(peer, "socket", name, sock->listen) == -1) {
+        if (net_socket_listen_init(peer, "socket", name, sock->listen, errp)
+            < 0) {
             return -1;
         }
         return 0;
     }
 
     if (sock->has_connect) {
-        if (net_socket_connect_init(peer, "socket", name, sock->connect) ==
-            -1) {
+        if (net_socket_connect_init(peer, "socket", name, sock->connect, errp)
+            < 0) {
             return -1;
         }
         return 0;
@@ -746,7 +742,7 @@ int net_init_socket(const Netdev *netdev, const char *name,
         /* if sock->localaddr is missing, it has been initialized to "all bits
          * zero" */
         if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
-            sock->localaddr) == -1) {
+            sock->localaddr, errp) < 0) {
             return -1;
         }
         return 0;
@@ -754,11 +750,11 @@ int net_init_socket(const Netdev *netdev, const char *name,
 
     assert(sock->has_udp);
     if (!sock->has_localaddr) {
-        error_report("localaddr= is mandatory with udp=");
+        error_setg(errp, "localaddr= is mandatory with udp=");
         return -1;
     }
-    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
-        -1) {
+    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr,
+        errp) < 0) {
         return -1;
     }
     return 0;
-- 
2.9.4

Re: [Qemu-devel] [PATCH v8 2/4] net/socket: Convert several helper functions to Error

[Markus Armbruster]

Mao Zhongyi <maozy.fnst@cn.fujitsu.com> writes:

> Currently, net_socket_mcast_create(), net_socket_fd_init_dgram() and
> net_socket_fd_init() use the function such as fprintf(), perror() to
> report an error message.
>
> Now, convert these functions to Error.
>
> Cc: jasowang@redhat.com
> Cc: armbru@redhat.com
> Cc: berrange@redhat.com
> Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
> Reviewed-by: Daniel P. Berrange <berrange@redhat.com>

Reviewed-by: Markus Armbruster <armbru@redhat.com>

Re: [Qemu-devel] [PATCH v8 4/4] net/socket: Improve -net socket error reporting

[Markus Armbruster]

Mao Zhongyi <maozy.fnst@cn.fujitsu.com> writes:

> When -net socket fails, it first reports a specific error, then
> a generic one, like this:
>
>     $ qemu-system-x86_64 -net socket,
>     qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required
>     qemu-system-x86_64: -net socket: Device 'socket' could not be initialized
>
> Convert net_socket_*_init() to Error to get rid of the superfluous second
> error message. After the patch, the effect like this:
>
>     $ qemu-system-x86_64 -net socket,
>     qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required
>
> At the same time, add many explicit error handling message when it fails.

Suggest "This also fixes a few silent failures to report an error."

Perhaps Jason can touch this up for you.

> Cc: jasowang@redhat.com
> Cc: armbru@redhat.com
> Cc: berrange@redhat.com
> Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
> ---
>  net/socket.c | 92 +++++++++++++++++++++++++++++-------------------------------
>  1 file changed, 44 insertions(+), 48 deletions(-)
>
> diff --git a/net/socket.c b/net/socket.c
> index 1d4c515..ca1878f 100644
> --- a/net/socket.c
> +++ b/net/socket.c
[...]
> @@ -746,7 +742,7 @@ int net_init_socket(const Netdev *netdev, const char *name,
>          /* if sock->localaddr is missing, it has been initialized to "all bits
>           * zero" */
>          if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
> -            sock->localaddr) == -1) {
> +            sock->localaddr, errp) < 0) {

Indent like this:

                                     sock->localaddr, errp) < 0) {

Perhaps Jason can touch this up for you.

>              return -1;
>          }
>          return 0;
> @@ -754,11 +750,11 @@ int net_init_socket(const Netdev *netdev, const char *name,
>  
>      assert(sock->has_udp);
>      if (!sock->has_localaddr) {
> -        error_report("localaddr= is mandatory with udp=");
> +        error_setg(errp, "localaddr= is mandatory with udp=");
>          return -1;
>      }
> -    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
> -        -1) {
> +    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr,
> +        errp) < 0) {

Likewise.

>          return -1;
>      }
>      return 0;

With the indentation fixed:
Reviewed-by: Markus Armbruster <armbru@redhat.com>

Re: [Qemu-devel] [PATCH v8 4/4] net/socket: Improve -net socket error reporting

[Mao Zhongyi]

Hi, Markus

On 07/06/2017 03:24 PM, Markus Armbruster wrote:
> Mao Zhongyi <maozy.fnst@cn.fujitsu.com> writes:
>
>> When -net socket fails, it first reports a specific error, then
>> a generic one, like this:
>>
>>     $ qemu-system-x86_64 -net socket,
>>     qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required
>>     qemu-system-x86_64: -net socket: Device 'socket' could not be initialized
>>
>> Convert net_socket_*_init() to Error to get rid of the superfluous second
>> error message. After the patch, the effect like this:
>>
>>     $ qemu-system-x86_64 -net socket,
>>     qemu-system-x86_64: -net socket: exactly one of fd=, listen=, connect=, mcast= or udp= is required
>>
>> At the same time, add many explicit error handling message when it fails.
>
> Suggest "This also fixes a few silent failures to report an error."
>
> Perhaps Jason can touch this up for you.
>
>> Cc: jasowang@redhat.com
>> Cc: armbru@redhat.com
>> Cc: berrange@redhat.com
>> Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
>> ---
>>  net/socket.c | 92 +++++++++++++++++++++++++++++-------------------------------
>>  1 file changed, 44 insertions(+), 48 deletions(-)
>>
>> diff --git a/net/socket.c b/net/socket.c
>> index 1d4c515..ca1878f 100644
>> --- a/net/socket.c
>> +++ b/net/socket.c
> [...]
>> @@ -746,7 +742,7 @@ int net_init_socket(const Netdev *netdev, const char *name,
>>          /* if sock->localaddr is missing, it has been initialized to "all bits
>>           * zero" */
>>          if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
>> -            sock->localaddr) == -1) {
>> +            sock->localaddr, errp) < 0) {
>
> Indent like this:
>
>                                      sock->localaddr, errp) < 0) {
>
> Perhaps Jason can touch this up for you.
>
>>              return -1;
>>          }
>>          return 0;
>> @@ -754,11 +750,11 @@ int net_init_socket(const Netdev *netdev, const char *name,
>>
>>      assert(sock->has_udp);
>>      if (!sock->has_localaddr) {
>> -        error_report("localaddr= is mandatory with udp=");
>> +        error_setg(errp, "localaddr= is mandatory with udp=");
>>          return -1;
>>      }
>> -    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
>> -        -1) {
>> +    if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr,
>> +        errp) < 0) {
>
> Likewise.
>
>>          return -1;
>>      }
>>      return 0;
>
> With the indentation fixed:

Thanks for your review :)
I will fix and resend it as soon as possible.

Thanks,
Mao

> Reviewed-by: Markus Armbruster <armbru@redhat.com>
>
>
>

[Qemu-devel] [PATCH v8 2/4] net/socket: Convert several helper functions to Error

[Mao Zhongyi]

Currently, net_socket_mcast_create(), net_socket_fd_init_dgram() and
net_socket_fd_init() use the function such as fprintf(), perror() to
report an error message.

Now, convert these functions to Error.

Cc: jasowang@redhat.com
Cc: armbru@redhat.com
Cc: berrange@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
 net/socket.c | 80 ++++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 48 insertions(+), 32 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index 7d05e70..3dd4459 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -209,7 +209,9 @@ static void net_socket_send_dgram(void *opaque)
     }
 }
 
-static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr *localaddr)
+static int net_socket_mcast_create(struct sockaddr_in *mcastaddr,
+                                   struct in_addr *localaddr,
+                                   Error **errp)
 {
     struct ip_mreq imr;
     int fd;
@@ -221,16 +223,16 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
 #endif
 
     if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
-        fprintf(stderr, "qemu: error: specified mcastaddr \"%s\" (0x%08x) "
-                "does not contain a multicast address\n",
-                inet_ntoa(mcastaddr->sin_addr),
-                (int)ntohl(mcastaddr->sin_addr.s_addr));
+        error_setg(errp, "specified mcastaddr %s (0x%08x) "
+                   "does not contain a multicast address",
+                   inet_ntoa(mcastaddr->sin_addr),
+                   (int)ntohl(mcastaddr->sin_addr.s_addr));
         return -1;
-
     }
+
     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
     if (fd < 0) {
-        perror("socket(PF_INET, SOCK_DGRAM)");
+        error_setg_errno(errp, errno, "can't create datagram socket");
         return -1;
     }
 
@@ -242,13 +244,15 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     val = 1;
     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
     if (ret < 0) {
-        perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
+        error_setg_errno(errp, errno,
+                         "can't set socket option SO_REUSEADDR");
         goto fail;
     }
 
     ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
     if (ret < 0) {
-        perror("bind");
+        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                         inet_ntoa(mcastaddr->sin_addr));
         goto fail;
     }
 
@@ -263,7 +267,9 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
                           &imr, sizeof(struct ip_mreq));
     if (ret < 0) {
-        perror("setsockopt(IP_ADD_MEMBERSHIP)");
+        error_setg_errno(errp, errno,
+                         "can't add socket to multicast group %s",
+                         inet_ntoa(imr.imr_multiaddr));
         goto fail;
     }
 
@@ -272,7 +278,8 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
                           &loop, sizeof(loop));
     if (ret < 0) {
-        perror("setsockopt(SOL_IP, IP_MULTICAST_LOOP)");
+        error_setg_errno(errp, errno,
+                         "can't force multicast message to loopback");
         goto fail;
     }
 
@@ -281,7 +288,8 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr
         ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
                               localaddr, sizeof(*localaddr));
         if (ret < 0) {
-            perror("setsockopt(IP_MULTICAST_IF)");
+            error_setg_errno(errp, errno,
+                             "can't set the default network send interface");
             goto fail;
         }
     }
@@ -320,7 +328,8 @@ static NetClientInfo net_dgram_socket_info = {
 static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
                                                 const char *model,
                                                 const char *name,
-                                                int fd, int is_connected)
+                                                int fd, int is_connected,
+                                                Error **errp)
 {
     struct sockaddr_in saddr;
     int newfd;
@@ -337,14 +346,12 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
         if (getsockname(fd, (struct sockaddr *) &saddr, &saddr_len) == 0) {
             /* must be bound */
             if (saddr.sin_addr.s_addr == 0) {
-                fprintf(stderr, "qemu: error: init_dgram: fd=%d unbound, "
-                        "cannot setup multicast dst addr\n", fd);
+                error_setg(errp, "can't setup multicast destination address");
                 goto err;
             }
             /* clone dgram socket */
-            newfd = net_socket_mcast_create(&saddr, NULL);
+            newfd = net_socket_mcast_create(&saddr, NULL, errp);
             if (newfd < 0) {
-                /* error already reported by net_socket_mcast_create() */
                 goto err;
             }
             /* clone newfd to fd, close newfd */
@@ -352,9 +359,7 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
             close(newfd);
 
         } else {
-            fprintf(stderr,
-                    "qemu: error: init_dgram: fd=%d failed getsockname(): %s\n",
-                    fd, strerror(errno));
+            error_setg_errno(errp, errno, "can't get socket name");
             goto err;
         }
     }
@@ -432,20 +437,21 @@ static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 
 static NetSocketState *net_socket_fd_init(NetClientState *peer,
                                           const char *model, const char *name,
-                                          int fd, int is_connected)
+                                          int fd, int is_connected,
+                                          Error **errp)
 {
     int so_type = -1, optlen=sizeof(so_type);
 
     if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
         (socklen_t *)&optlen)< 0) {
-        fprintf(stderr, "qemu: error: getsockopt(SO_TYPE) for fd=%d failed\n",
-                fd);
+        error_setg(errp, "can't get socket option SO_TYPE");
         closesocket(fd);
         return NULL;
     }
     switch(so_type) {
     case SOCK_DGRAM:
-        return net_socket_fd_init_dgram(peer, model, name, fd, is_connected);
+        return net_socket_fd_init_dgram(peer, model, name, fd, is_connected,
+                                        errp);
     case SOCK_STREAM:
         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
     default:
@@ -536,6 +542,7 @@ static int net_socket_connect_init(NetClientState *peer,
     NetSocketState *s;
     int fd, connected, ret;
     struct sockaddr_in saddr;
+    Error *err = NULL;
 
     if (parse_host_port(&saddr, host_str) < 0)
         return -1;
@@ -567,9 +574,11 @@ static int net_socket_connect_init(NetClientState *peer,
             break;
         }
     }
-    s = net_socket_fd_init(peer, model, name, fd, connected);
-    if (!s)
+    s = net_socket_fd_init(peer, model, name, fd, connected, &err);
+    if (!s) {
+        error_report_err(err);
         return -1;
+    }
     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
              "socket: connect to %s:%d",
              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
@@ -586,6 +595,7 @@ static int net_socket_mcast_init(NetClientState *peer,
     int fd;
     struct sockaddr_in saddr;
     struct in_addr localaddr, *param_localaddr;
+    Error *err = NULL;
 
     if (parse_host_port(&saddr, host_str) < 0)
         return -1;
@@ -598,13 +608,17 @@ static int net_socket_mcast_init(NetClientState *peer,
         param_localaddr = NULL;
     }
 
-    fd = net_socket_mcast_create(&saddr, param_localaddr);
-    if (fd < 0)
+    fd = net_socket_mcast_create(&saddr, param_localaddr, &err);
+    if (fd < 0) {
+        error_report_err(err);
         return -1;
+    }
 
-    s = net_socket_fd_init(peer, model, name, fd, 0);
-    if (!s)
+    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
+    if (!s) {
+        error_report_err(err);
         return -1;
+    }
 
     s->dgram_dst = saddr;
 
@@ -624,6 +638,7 @@ static int net_socket_udp_init(NetClientState *peer,
     NetSocketState *s;
     int fd, ret;
     struct sockaddr_in laddr, raddr;
+    Error *err = NULL;
 
     if (parse_host_port(&laddr, lhost) < 0) {
         return -1;
@@ -652,8 +667,9 @@ static int net_socket_udp_init(NetClientState *peer,
     }
     qemu_set_nonblock(fd);
 
-    s = net_socket_fd_init(peer, model, name, fd, 0);
+    s = net_socket_fd_init(peer, model, name, fd, 0, &err);
     if (!s) {
+        error_report_err(err);
         return -1;
     }
 
@@ -696,7 +712,7 @@ int net_init_socket(const Netdev *netdev, const char *name,
             return -1;
         }
         qemu_set_nonblock(fd);
-        if (!net_socket_fd_init(peer, "socket", name, fd, 1)) {
+        if (!net_socket_fd_init(peer, "socket", name, fd, 1, errp)) {
             return -1;
         }
         return 0;
-- 
2.9.4