[Qemu-devel] [PATCH v2 18/18] osdep: remove use of socket_error() from all code

[Daniel P. Berrange]

Now that QEMU wraps the Win32 sockets methods to automatically
set errno upon failure, there is no reason for callers to use
the socket_error() method. They can rely on accessing errno
even on Win32. Remove all use of socket_error() from general
code, leaving it as a static method in oslib-win32.c only.

Signed-off-by: Daniel P. Berrange <address@hidden>
---
 block/sheepdog.c           |  5 ++---
 include/sysemu/os-posix.h  |  2 --
 include/sysemu/os-win32.h  |  2 --
 io/channel-socket.c        | 38 +++++++++++++++++++-------------------
 migration/qemu-file-unix.c | 14 ++++++--------
 migration/tcp.c            |  7 +++----
 net/socket.c               | 19 ++++++++-----------
 slirp/tcp_input.c          |  4 ----
 util/oslib-win32.c         |  2 +-
 util/qemu-coroutine-io.c   |  6 ++----
 util/qemu-sockets.c        | 10 +++++-----
 11 files changed, 46 insertions(+), 63 deletions(-)

diff --git a/block/sheepdog.c b/block/sheepdog.c
index 8739acc..05677ed 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -615,14 +615,13 @@ static coroutine_fn int send_co_req(int sockfd, 
SheepdogReq *hdr, void *data,
     ret = qemu_co_send(sockfd, hdr, sizeof(*hdr));
     if (ret != sizeof(*hdr)) {
         error_report("failed to send a req, %s", strerror(errno));
-        ret = -socket_error();
-        return ret;
+        return -errno;
     }
 
     ret = qemu_co_send(sockfd, data, *wlen);
     if (ret != *wlen) {
-        ret = -socket_error();
         error_report("failed to send a req, %s", strerror(errno));
+        return -errno;
     }
 
     return ret;
diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h
index 53fac98..07e3e5a 100644
--- a/include/sysemu/os-posix.h
+++ b/include/sysemu/os-posix.h
@@ -40,8 +40,6 @@ void os_daemonize(void);
 void os_setup_post(void);
 int os_mlock(void);
 
-#define socket_error() errno
-
 #define closesocket(s) close(s)
 #define ioctlsocket(s, r, v) ioctl(s, r, v)
 
diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
index 6905066..17aad3b 100644
--- a/include/sysemu/os-win32.h
+++ b/include/sysemu/os-win32.h
@@ -55,8 +55,6 @@ struct tm *gmtime_r(const time_t *timep, struct tm *result);
 struct tm *localtime_r(const time_t *timep, struct tm *result);
 #endif /* CONFIG_LOCALTIME_R */
 
-int socket_error(void);
-
 static inline void os_setup_signal_handling(void) {}
 static inline void os_daemonize(void) {}
 static inline void os_setup_post(void) {}
diff --git a/io/channel-socket.c b/io/channel-socket.c
index ae67ab1..d005070 100644
--- a/io/channel-socket.c
+++ b/io/channel-socket.c
@@ -82,11 +82,11 @@ qio_channel_socket_set_fd(QIOChannelSocket *sioc,
 
     if (getpeername(fd, (struct sockaddr *)&sioc->remoteAddr,
                     &sioc->remoteAddrLen) < 0) {
-        if (socket_error() == ENOTCONN) {
+        if (errno == ENOTCONN) {
             memset(&sioc->remoteAddr, 0, sizeof(sioc->remoteAddr));
             sioc->remoteAddrLen = sizeof(sioc->remoteAddr);
         } else {
-            error_setg_errno(errp, socket_error(),
+            error_setg_errno(errp, errno,
                              "Unable to query remote socket address");
             goto error;
         }
@@ -94,7 +94,7 @@ qio_channel_socket_set_fd(QIOChannelSocket *sioc,
 
     if (getsockname(fd, (struct sockaddr *)&sioc->localAddr,
                     &sioc->localAddrLen) < 0) {
-        error_setg_errno(errp, socket_error(),
+        error_setg_errno(errp, errno,
                          "Unable to query local socket address");
         goto error;
     }
@@ -356,7 +356,7 @@ qio_channel_socket_accept(QIOChannelSocket *ioc,
                            &cioc->remoteAddrLen);
     if (cioc->fd < 0) {
         trace_qio_channel_socket_accept_fail(ioc);
-        if (socket_error() == EINTR) {
+        if (errno == EINTR) {
             goto retry;
         }
         goto error;
@@ -364,7 +364,7 @@ qio_channel_socket_accept(QIOChannelSocket *ioc,
 
     if (getsockname(cioc->fd, (struct sockaddr *)&cioc->localAddr,
                     &cioc->localAddrLen) < 0) {
-        error_setg_errno(errp, socket_error(),
+        error_setg_errno(errp, errno,
                          "Unable to query local socket address");
         goto error;
     }
@@ -478,14 +478,14 @@ static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
  retry:
     ret = recvmsg(sioc->fd, &msg, sflags);
     if (ret < 0) {
-        if (socket_error() == EAGAIN) {
+        if (errno == EAGAIN) {
             return QIO_CHANNEL_ERR_BLOCK;
         }
-        if (socket_error() == EINTR) {
+        if (errno == EINTR) {
             goto retry;
         }
 
-        error_setg_errno(errp, socket_error(),
+        error_setg_errno(errp, errno,
                          "Unable to read from socket");
         return -1;
     }
@@ -537,13 +537,13 @@ static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
  retry:
     ret = sendmsg(sioc->fd, &msg, 0);
     if (ret <= 0) {
-        if (socket_error() == EAGAIN) {
+        if (errno == EAGAIN) {
             return QIO_CHANNEL_ERR_BLOCK;
         }
-        if (socket_error() == EINTR) {
+        if (errno == EINTR) {
             goto retry;
         }
-        error_setg_errno(errp, socket_error(),
+        error_setg_errno(errp, errno,
                          "Unable to write to socket");
         return -1;
     }
@@ -569,16 +569,16 @@ static ssize_t qio_channel_socket_readv(QIOChannel *ioc,
                    iov[i].iov_len,
                    0);
         if (ret < 0) {
-            if (socket_error() == EAGAIN) {
+            if (errno == EAGAIN) {
                 if (done) {
                     return done;
                 } else {
                     return QIO_CHANNEL_ERR_BLOCK;
                 }
-            } else if (socket_error() == EINTR) {
+            } else if (errno == EINTR) {
                 goto retry;
             } else {
-                error_setg_errno(errp, socket_error(),
+                error_setg_errno(errp, errno,
                                  "Unable to read from socket");
                 return -1;
             }
@@ -611,16 +611,16 @@ static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
                    iov[i].iov_len,
                    0);
         if (ret < 0) {
-            if (socket_error() == EAGAIN) {
+            if (errno == EAGAIN) {
                 if (done) {
                     return done;
                 } else {
                     return QIO_CHANNEL_ERR_BLOCK;
                 }
-            } else if (socket_error() == EINTR) {
+            } else if (errno == EINTR) {
                 goto retry;
             } else {
-                error_setg_errno(errp, socket_error(),
+                error_setg_errno(errp, errno,
                                  "Unable to write to socket");
                 return -1;
             }
@@ -692,7 +692,7 @@ qio_channel_socket_close(QIOChannel *ioc,
 #endif
         if (closesocket(sioc->fd) < 0) {
             sioc->fd = -1;
-            error_setg_errno(errp, socket_error(),
+            error_setg_errno(errp, errno,
                              "Unable to close socket");
             return -1;
         }
@@ -723,7 +723,7 @@ qio_channel_socket_shutdown(QIOChannel *ioc,
     }
 
     if (shutdown(sioc->fd, sockhow) < 0) {
-        error_setg_errno(errp, socket_error(),
+        error_setg_errno(errp, errno,
                          "Unable to shutdown socket");
         return -1;
     }
diff --git a/migration/qemu-file-unix.c b/migration/qemu-file-unix.c
index 61b059b..4474e18 100644
--- a/migration/qemu-file-unix.c
+++ b/migration/qemu-file-unix.c
@@ -53,18 +53,16 @@ static ssize_t socket_writev_buffer(void *opaque, struct 
iovec *iov, int iovcnt,
         }
 
         if (size > 0) {
-            err = socket_error();
-
-            if (err != EAGAIN && err != EWOULDBLOCK) {
+            if (errno != EAGAIN && errno != EWOULDBLOCK) {
                 error_report("socket_writev_buffer: Got err=%d for (%zu/%zu)",
-                             err, (size_t)size, (size_t)len);
+                             errno, (size_t)size, (size_t)len);
                 /*
                  * If I've already sent some but only just got the error, I
                  * could return the amount validly sent so far and wait for the
                  * next call to report the error, but I'd rather flag the error
                  * immediately.
                  */
-                return -err;
+                return -errno;
             }
 
             /* Emulate blocking */
@@ -99,15 +97,15 @@ static ssize_t socket_get_buffer(void *opaque, uint8_t 
*buf, int64_t pos,
         if (len != -1) {
             break;
         }
-        if (socket_error() == EAGAIN) {
+        if (errno == EAGAIN) {
             yield_until_fd_readable(s->fd);
-        } else if (socket_error() != EINTR) {
+        } else if (errno != EINTR) {
             break;
         }
     }
 
     if (len == -1) {
-        len = -socket_error();
+        len = -errno;
     }
     return len;
 }
diff --git a/migration/tcp.c b/migration/tcp.c
index e888a4e..e1fa7f8 100644
--- a/migration/tcp.c
+++ b/migration/tcp.c
@@ -59,12 +59,11 @@ static void tcp_accept_incoming_migration(void *opaque)
     socklen_t addrlen = sizeof(addr);
     int s = (intptr_t)opaque;
     QEMUFile *f;
-    int c, err;
+    int c;
 
     do {
         c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
-        err = socket_error();
-    } while (c < 0 && err == EINTR);
+    } while (c < 0 && errno == EINTR);
     qemu_set_fd_handler(s, NULL, NULL, NULL);
     closesocket(s);
 
@@ -72,7 +71,7 @@ static void tcp_accept_incoming_migration(void *opaque)
 
     if (c < 0) {
         error_report("could not accept migration connection (%s)",
-                     strerror(err));
+                     strerror(errno));
         return;
     }
 
diff --git a/net/socket.c b/net/socket.c
index e32e3cb..73dc49a 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -145,15 +145,14 @@ static void net_socket_send_completed(NetClientState *nc, 
ssize_t len)
 static void net_socket_send(void *opaque)
 {
     NetSocketState *s = opaque;
-    int size, err;
+    int size;
     unsigned l;
     uint8_t buf1[NET_BUFSIZE];
     const uint8_t *buf;
 
     size = qemu_recv(s->fd, buf1, sizeof(buf1), 0);
     if (size < 0) {
-        err = socket_error();
-        if (err != EWOULDBLOCK)
+        if (errno != EWOULDBLOCK)
             goto eoc;
     } else if (size == 0) {
         /* end of connection */
@@ -566,7 +565,7 @@ static int net_socket_connect_init(NetClientState *peer,
                                    const char *host_str)
 {
     NetSocketState *s;
-    int fd, connected, ret, err;
+    int fd, connected, ret;
     struct sockaddr_in saddr;
 
     if (parse_host_port(&saddr, host_str) < 0)
@@ -583,14 +582,12 @@ static int net_socket_connect_init(NetClientState *peer,
     for(;;) {
         ret = connect(fd, (struct sockaddr *)&saddr, sizeof(saddr));
         if (ret < 0) {
-            err = socket_error();
-            if (err == EINTR || err == EWOULDBLOCK) {
-            } else if (err == EINPROGRESS) {
-                break;
-#ifdef _WIN32
-            } else if (err == WSAEALREADY || err == WSAEINVAL) {
+            if (errno == EINTR || errno == EWOULDBLOCK) {
+                /* continue */
+            } else if (errno == EINPROGRESS ||
+                       errno == EALREADY ||
+                       errno == EINVAL) {
                 break;
-#endif
             } else {
                 perror("connect");
                 closesocket(fd);
diff --git a/slirp/tcp_input.c b/slirp/tcp_input.c
index 2027a75..03be56e 100644
--- a/slirp/tcp_input.c
+++ b/slirp/tcp_input.c
@@ -586,11 +586,7 @@ findso:
          }
 
          if ((tcp_fconnect(so, so->so_ffamily) == -1) &&
-#if defined(_WIN32)
-              socket_error() != WSAEWOULDBLOCK
-#else
               (errno != EINPROGRESS) && (errno != EWOULDBLOCK)
-#endif
           ) {
            u_char code=ICMP_UNREACH_NET;
            DEBUG_MISC((dfd, " tcp fconnect errno = %d-%s\n",
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index a6256de..a3f0664 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -145,7 +145,7 @@ int socket_set_fast_reuse(int fd)
 }
 
 
-int socket_error(void)
+static int socket_error(void)
 {
     switch (WSAGetLastError()) {
     case 0:
diff --git a/util/qemu-coroutine-io.c b/util/qemu-coroutine-io.c
index 0d5041c..91b9357 100644
--- a/util/qemu-coroutine-io.c
+++ b/util/qemu-coroutine-io.c
@@ -35,18 +35,16 @@ qemu_co_sendv_recvv(int sockfd, struct iovec *iov, unsigned 
iov_cnt,
 {
     size_t done = 0;
     ssize_t ret;
-    int err;
     while (done < bytes) {
         ret = iov_send_recv(sockfd, iov, iov_cnt,
                             offset + done, bytes - done, do_send);
         if (ret > 0) {
             done += ret;
         } else if (ret < 0) {
-            err = socket_error();
-            if (err == EAGAIN || err == EWOULDBLOCK) {
+            if (errno == EAGAIN || errno == EWOULDBLOCK) {
                 qemu_coroutine_yield();
             } else if (done == 0) {
-                return -err;
+                return -errno;
             } else {
                 break;
             }
diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index ad7c00c..fd37ac2 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -268,7 +268,7 @@ static void wait_for_connect(void *opaque)
 
     do {
         rc = qemu_getsockopt(s->fd, SOL_SOCKET, SO_ERROR, &val, &valsize);
-    } while (rc == -1 && socket_error() == EINTR);
+    } while (rc == -1 && errno == EINTR);
 
     /* update rc to contain error */
     if (!rc && val) {
@@ -330,7 +330,7 @@ static int inet_connect_addr(struct addrinfo *addr, bool 
*in_progress,
     do {
         rc = 0;
         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
-            rc = -socket_error();
+            rc = -errno;
         }
     } while (rc == -EINTR);
 
@@ -787,7 +787,7 @@ static int unix_connect_saddr(UnixSocketAddress *saddr, 
Error **errp,
     do {
         rc = 0;
         if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
-            rc = -socket_error();
+            rc = -errno;
         }
     } while (rc == -EINTR);
 
@@ -1082,7 +1082,7 @@ SocketAddress *socket_local_address(int fd, Error **errp)
     socklen_t sslen = sizeof(ss);
 
     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
-        error_setg_errno(errp, socket_error(), "%s",
+        error_setg_errno(errp, errno, "%s",
                          "Unable to query local socket address");
         return NULL;
     }
@@ -1097,7 +1097,7 @@ SocketAddress *socket_remote_address(int fd, Error **errp)
     socklen_t sslen = sizeof(ss);
 
     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
-        error_setg_errno(errp, socket_error(), "%s",
+        error_setg_errno(errp, errno, "%s",
                          "Unable to query remote socket address");
         return NULL;
     }
-- 
2.5.0