diff options
| author | Diego Elio 'Flameeyes' Pettenò <flameeyes@gmail.com> | 2010-09-03 07:47:03 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-09-09 00:08:05 +0400 |
| commit | 65040c33ee8d0199ab7686402bffdbf9e1e26cbe (patch) | |
| tree | 4c8a35d0b6da2964a0de8f6668c0f5f47efe2825 /net/sctp | |
| parent | 2edae08e5b75269855fef3c74fe4292c066e7c33 (diff) | |
| download | linux-65040c33ee8d0199ab7686402bffdbf9e1e26cbe.tar.xz | |
sctp: implement SIOCINQ ioctl() (take 3)
This simple patch copies the current approach for SIOCINQ ioctl() from DCCP
into SCTP so that the userland code working with SCTP can use a similar
interface across different protocols to know how much space to allocate for
a buffer.
Signed-off-by: Diego Elio Pettenò <flameeyes@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sctp')
| -rw-r--r-- | net/sctp/socket.c | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index cf6dcc908b88..6a691d84aef4 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3592,7 +3592,40 @@ out: /* The SCTP ioctl handler. */ SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg) { - return -ENOIOCTLCMD; + int rc = -ENOTCONN; + + sctp_lock_sock(sk); + + /* + * SEQPACKET-style sockets in LISTENING state are valid, for + * SCTP, so only discard TCP-style sockets in LISTENING state. + */ + if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) + goto out; + + switch (cmd) { + case SIOCINQ: { + struct sk_buff *skb; + unsigned int amount = 0; + + skb = skb_peek(&sk->sk_receive_queue); + if (skb != NULL) { + /* + * We will only return the amount of this packet since + * that is all that will be read. + */ + amount = skb->len; + } + rc = put_user(amount, (int __user *)arg); + } + break; + default: + rc = -ENOIOCTLCMD; + break; + } +out: + sctp_release_sock(sk); + return rc; } /* This is the function which gets called during socket creation to |