[PATCH 3/9] UML - multicast driver cleanup

From: Jeff Dike
Date: Tue May 17 2005 - 23:40:49 EST


Byte-swapping of the port and IP address passed in to the multicast driver
by the user used to happen in different places, which was a bug in itself.
The port also was swapped before being printk-ed, which led to a misleading
message. This patch moves the port swapping to the same place as the IP
address swapping.
It also cleans up the error paths of mcast_open.

Signed-off-by: Jeff Dike <jdike@xxxxxxxxxxx>

Index: linux-2.6.12-rc/arch/um/drivers/mcast_kern.c
===================================================================
--- linux-2.6.12-rc.orig/arch/um/drivers/mcast_kern.c 2005-05-17 18:02:25.000000000 -0400
+++ linux-2.6.12-rc/arch/um/drivers/mcast_kern.c 2005-05-17 18:07:03.000000000 -0400
@@ -73,7 +73,6 @@ int mcast_setup(char *str, char **mac_ou
struct mcast_init *init = data;
char *port_str = NULL, *ttl_str = NULL, *remain;
char *last;
- int n;

*init = ((struct mcast_init)
{ .addr = "239.192.168.1",
@@ -89,13 +88,12 @@ int mcast_setup(char *str, char **mac_ou
}

if(port_str != NULL){
- n = simple_strtoul(port_str, &last, 10);
+ init->port = simple_strtoul(port_str, &last, 10);
if((*last != '\0') || (last == port_str)){
printk(KERN_ERR "mcast_setup - Bad port : '%s'\n",
port_str);
return(0);
}
- init->port = htons(n);
}

if(ttl_str != NULL){
Index: linux-2.6.12-rc/arch/um/drivers/mcast_user.c
===================================================================
--- linux-2.6.12-rc.orig/arch/um/drivers/mcast_user.c 2005-05-17 18:02:25.000000000 -0400
+++ linux-2.6.12-rc/arch/um/drivers/mcast_user.c 2005-05-17 18:07:10.000000000 -0400
@@ -38,7 +38,7 @@ static struct sockaddr_in *new_addr(char
}
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = in_aton(addr);
- sin->sin_port = port;
+ sin->sin_port = htons(port);
return(sin);
}

@@ -55,28 +55,25 @@ static int mcast_open(void *data)
struct mcast_data *pri = data;
struct sockaddr_in *sin = pri->mcast_addr;
struct ip_mreq mreq;
- int fd, yes = 1;
+ int fd = -EINVAL, yes = 1, err = -EINVAL;;


- if ((sin->sin_addr.s_addr == 0) || (sin->sin_port == 0)) {
- fd = -EINVAL;
+ if ((sin->sin_addr.s_addr == 0) || (sin->sin_port == 0))
goto out;
- }

fd = socket(AF_INET, SOCK_DGRAM, 0);
+
if (fd < 0){
printk("mcast_open : data socket failed, errno = %d\n",
errno);
- fd = -ENOMEM;
+ fd = -errno;
goto out;
}

if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
printk("mcast_open: SO_REUSEADDR failed, errno = %d\n",
errno);
- os_close_file(fd);
- fd = -EINVAL;
- goto out;
+ goto out_close;
}

/* set ttl according to config */
@@ -84,26 +81,20 @@ static int mcast_open(void *data)
sizeof(pri->ttl)) < 0) {
printk("mcast_open: IP_MULTICAST_TTL failed, error = %d\n",
errno);
- os_close_file(fd);
- fd = -EINVAL;
- goto out;
+ goto out_close;
}

/* set LOOP, so data does get fed back to local sockets */
if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP, &yes, sizeof(yes)) < 0) {
printk("mcast_open: IP_MULTICAST_LOOP failed, error = %d\n",
errno);
- os_close_file(fd);
- fd = -EINVAL;
- goto out;
+ goto out_close;
}

/* bind socket to mcast address */
if (bind(fd, (struct sockaddr *) sin, sizeof(*sin)) < 0) {
printk("mcast_open : data bind failed, errno = %d\n", errno);
- os_close_file(fd);
- fd = -EINVAL;
- goto out;
+ goto out_close;
}

/* subscribe to the multicast group */
@@ -117,12 +108,15 @@ static int mcast_open(void *data)
"interface on the host.\n");
printk("eth0 should be configured in order to use the "
"multicast transport.\n");
- os_close_file(fd);
- fd = -EINVAL;
+ goto out_close;
}

out:
- return(fd);
+ return fd;
+
+ out_close:
+ os_close_file(fd);
+ return err;
}

static void mcast_close(int fd, void *data)
@@ -164,14 +158,3 @@ struct net_user_info mcast_user_info = {
.delete_address = NULL,
.max_packet = MAX_PACKET - ETH_HEADER_OTHER
};
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only. This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */

-
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