[Qemu-devel] [PATCH 3/3] sockets: switch over tcp/telnet/unix serial line to new helper functions.

[Gerd Hoffmann <kraxel@redhat.com>]

This switches the tcp, telnet and unix socket support for character
devices (serial/parallel, ...) to the new socket helpers.  Thereby they
gain IPv6 support and also get ability to search for a free tcp port.
Syntax is the same as for vnc, using a to= option, like this:

	-serial tcp:localhost:5000,to=5099,server

This will check the 5000 -> 5099 port range (inclusive) for a free tcp
port.  Likewise you can get auto-allocated unix sockets by specifying an
empty path:

	-serial unix:,server

qemu will create a randomly named socket in $TMPDIR then.

tcp also got new "ipv4" and "ipv6" options to make qemu try only the
specified internet protocol version.

You can use the "info chardev" command added by the first patch in this
series to figure the tcp port / unix socket actually allocated.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 qemu-char.c |  106 ++++++++++++++++++-----------------------------------------
 1 files changed, 32 insertions(+), 74 deletions(-)

diff --git a/qemu-char.c b/qemu-char.c
index ceffbed..906e817 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -1951,32 +1951,11 @@ static CharDriverState *qemu_chr_open_tcp(const char *host_str,
 {
     CharDriverState *chr = NULL;
     TCPCharDriver *s = NULL;
-    int fd = -1, ret, err, val;
+    int fd = -1, offset = 0;
     int is_listen = 0;
     int is_waitconnect = 1;
     int do_nodelay = 0;
     const char *ptr;
-    struct sockaddr_in saddr;
-#ifndef _WIN32
-    struct sockaddr_un uaddr;
-#endif
-    struct sockaddr *addr;
-    socklen_t addrlen;
-
-#ifndef _WIN32
-    if (is_unix) {
-	addr = (struct sockaddr *)&uaddr;
-	addrlen = sizeof(uaddr);
-	if (parse_unix_path(&uaddr, host_str) < 0)
-	    goto fail;
-    } else
-#endif
-    {
-	addr = (struct sockaddr *)&saddr;
-	addrlen = sizeof(saddr);
-	if (parse_host_port(&saddr, host_str) < 0)
-	    goto fail;
-    }
 
     ptr = host_str;
     while((ptr = strchr(ptr,','))) {
@@ -1987,6 +1966,8 @@ static CharDriverState *qemu_chr_open_tcp(const char *host_str,
             is_waitconnect = 0;
         } else if (!strncmp(ptr,"nodelay",6)) {
             do_nodelay = 1;
+        } else if (!strncmp(ptr,"to=",3)) {
+            /* nothing, inet_listen() parses this one */;
         } else {
             printf("Unknown option: %s\n", ptr);
             goto fail;
@@ -2002,13 +1983,31 @@ static CharDriverState *qemu_chr_open_tcp(const char *host_str,
     if (!s)
         goto fail;
 
-#ifndef _WIN32
-    if (is_unix)
-	fd = socket(PF_UNIX, SOCK_STREAM, 0);
-    else
-#endif
-	fd = socket(PF_INET, SOCK_STREAM, 0);
-
+    if (is_listen) {
+        chr->filename = qemu_malloc(256);
+        if (is_unix) {
+            strcpy(chr->filename, "unix:");
+        } else if (is_telnet) {
+            strcpy(chr->filename, "telnet:");
+        } else {
+            strcpy(chr->filename, "tcp:");
+        }
+        offset = strlen(chr->filename);
+    }
+    if (is_unix) {
+        if (is_listen) {
+            fd = unix_listen(host_str, chr->filename + offset, 256 - offset);
+        } else {
+            fd = unix_connect(host_str);
+        }
+    } else {
+        if (is_listen) {
+            fd = inet_listen(host_str, chr->filename + offset, 256 - offset,
+                             SOCK_STREAM, 0);
+        } else {
+            fd = inet_connect(host_str, SOCK_STREAM);
+        }
+    }
     if (fd < 0)
         goto fail;
 
@@ -2026,61 +2025,20 @@ static CharDriverState *qemu_chr_open_tcp(const char *host_str,
     chr->chr_close = tcp_chr_close;
 
     if (is_listen) {
-        /* allow fast reuse */
-#ifndef _WIN32
-	if (is_unix) {
-	    char path[109];
-	    pstrcpy(path, sizeof(path), uaddr.sun_path);
-	    unlink(path);
-	} else
-#endif
-	{
-	    val = 1;
-	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (const char *)&val, sizeof(val));
-	}
-
-        ret = bind(fd, addr, addrlen);
-        if (ret < 0)
-            goto fail;
-
-        ret = listen(fd, 0);
-        if (ret < 0)
-            goto fail;
-
         s->listen_fd = fd;
         qemu_set_fd_handler(s->listen_fd, tcp_chr_accept, NULL, chr);
         if (is_telnet)
             s->do_telnetopt = 1;
     } else {
-        for(;;) {
-            ret = connect(fd, addr, addrlen);
-            if (ret < 0) {
-                err = socket_error();
-                if (err == EINTR || err == EWOULDBLOCK) {
-                } else if (err == EINPROGRESS) {
-                    break;
-#ifdef _WIN32
-                } else if (err == WSAEALREADY) {
-                    break;
-#endif
-                } else {
-                    goto fail;
-                }
-            } else {
-                s->connected = 1;
-                break;
-            }
-        }
+        s->connected = 1;
         s->fd = fd;
         socket_set_nodelay(fd);
-        if (s->connected)
-            tcp_chr_connect(chr);
-        else
-            qemu_set_fd_handler(s->fd, NULL, tcp_chr_connect, chr);
+        tcp_chr_connect(chr);
     }
 
     if (is_listen && is_waitconnect) {
-        printf("QEMU waiting for connection on: %s\n", host_str);
+        printf("QEMU waiting for connection on: %s\n",
+               chr->filename ? chr->filename : host_str);
         tcp_chr_accept(chr);
         socket_set_nonblock(s->listen_fd);
     }
-- 
1.5.6.5