linux-user: add ioctl(SIOCGIWNAME, ...) support.

Allow to run properly following program from linux-user:

/* cc -o wifi wifi.c */

 #include <stdio.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <linux/wireless.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <string.h>

int main(int argc, char **argv)
{
    int ret;
    struct ifreq req;
    struct sockaddr_in *addr;
    int s;

    if (argc != 2) {
        fprintf(stderr, "Need an interface name (like wlan0)\n");
	return 1;
    }

    s = socket( AF_INET, SOCK_DGRAM, 0 );
    if (s < 0) {
        perror("Cannot open socket");
        return 1;
    }
    strncpy(req.ifr_name, argv[1], sizeof(req.ifr_name));
    ret = ioctl( s, SIOCGIWNAME, &req );
    if (ret < 0) {
	fprintf(stderr, "No wireless extension\n");
        return 1;
    }

    printf("%s\n", req.ifr_name);
    printf("%s\n", req.ifr_newname);
    return 0;
}

$ ./wifi eth0
No wireless extension

$ ./wifi wlan0
wlan0
IEEE 802.11bg

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@iki.fi>

linux-user/ioctls.h

@@ -122,6 +122,7 @@
   IOCTL(SIOCDRARP, IOC_W, MK_PTR(MK_STRUCT(STRUCT_arpreq)))
   IOCTL(SIOCSRARP, IOC_W, MK_PTR(MK_STRUCT(STRUCT_arpreq)))
   IOCTL(SIOCGRARP, IOC_R, MK_PTR(MK_STRUCT(STRUCT_arpreq)))
+  IOCTL(SIOCGIWNAME, IOC_W | IOC_R, MK_PTR(MK_STRUCT(STRUCT_char_ifreq)))
 
   IOCTL(CDROMPAUSE, 0, TYPE_NULL)
   IOCTL(CDROMSTART, 0, TYPE_NULL)

linux-user/syscall.c

@@ -59,7 +59,7 @@ int __clone2(int (*fn)(void *), void *child_stack_base,
 //#include <sys/user.h>
 #include <netinet/ip.h>
 #include <netinet/tcp.h>
-#include <net/if.h>
+#include <linux/wireless.h>
 #include <qemu-common.h>
 #ifdef TARGET_GPROF
 #include <sys/gmon.h>

linux-user/syscall_defs.h

@@ -765,6 +765,9 @@ struct target_pollfd {
 #define TARGET_SIOCADDDLCI     0x8980          /* Create new DLCI device       */
 #define TARGET_SIOCDELDLCI     0x8981          /* Delete DLCI device           */
 
+/* From <linux/wireless.h> */
+
+#define TARGET_SIOCGIWNAME     0x8B01          /* get name == wireless protocol */
 
 /* From <linux/fs.h> */