dccp ccid-3: Simplify and consolidate tx_parse_options

This simplifies and consolidates the TX option-parsing code:

 1. The Loss Intervals option is not currently used, so dead code related to
    this option is removed. I am aware of no plans to support the option, but
    if someone wants to implement it (e.g. for inter-op tests), it is better
    to start afresh than having to also update currently unused code.

 2. The Loss Event and Receive Rate options have a lot of code in common (both
    are 32 bit, both have same length etc.), so this is consolidated.

 3. The test against GSR is not necessary, because
    - on first loading CCID3, ccid_new() zeroes out all fields in the socket; 
    - ccid3_hc_tx_packet_recv() treats 0 and ~0U equivalently, due to

	pinv = opt_recv->ccid3or_loss_event_rate;
	if (pinv == ~0U || pinv == 0)
		hctx->p = 0;

    - as a result, the sequence number field is removed from opt_recv.
 
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
This commit is contained in:
Gerrit Renker 2008-09-04 07:30:19 +02:00
parent 63b3a73bb8
commit 47a61e7b43
2 changed files with 16 additions and 48 deletions

View File

@ -487,60 +487,31 @@ static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
unsigned char len, u16 idx,
unsigned char *value)
{
int rc = 0;
const struct dccp_sock *dp = dccp_sk(sk);
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
struct ccid3_options_received *opt_recv = &hctx->options_received;
__be32 opt_val;
if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
opt_recv->ccid3or_seqno = dp->dccps_gsr;
opt_recv->ccid3or_loss_event_rate = ~0;
opt_recv->ccid3or_loss_intervals_idx = 0;
opt_recv->ccid3or_loss_intervals_len = 0;
opt_recv->ccid3or_receive_rate = 0;
}
switch (option) {
case TFRC_OPT_RECEIVE_RATE:
case TFRC_OPT_LOSS_EVENT_RATE:
if (unlikely(len != 4)) {
DCCP_WARN("%s(%p), invalid len %d "
"for TFRC_OPT_LOSS_EVENT_RATE\n",
dccp_role(sk), sk, len);
rc = -EINVAL;
} else {
opt_val = get_unaligned((__be32 *)value);
opt_recv->ccid3or_loss_event_rate = ntohl(opt_val);
ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
dccp_role(sk), sk,
opt_recv->ccid3or_loss_event_rate);
DCCP_WARN("%s(%p), invalid len %d for %u\n",
dccp_role(sk), sk, len, option);
return -EINVAL;
}
break;
case TFRC_OPT_LOSS_INTERVALS:
opt_recv->ccid3or_loss_intervals_idx = idx;
opt_recv->ccid3or_loss_intervals_len = len;
ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n",
dccp_role(sk), sk,
opt_recv->ccid3or_loss_intervals_idx,
opt_recv->ccid3or_loss_intervals_len);
break;
case TFRC_OPT_RECEIVE_RATE:
if (unlikely(len != 4)) {
DCCP_WARN("%s(%p), invalid len %d "
"for TFRC_OPT_RECEIVE_RATE\n",
dccp_role(sk), sk, len);
rc = -EINVAL;
} else {
opt_val = get_unaligned((__be32 *)value);
opt_recv->ccid3or_receive_rate = ntohl(opt_val);
ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
dccp_role(sk), sk,
opt_recv->ccid3or_receive_rate);
}
break;
}
opt_val = ntohl(get_unaligned((__be32 *)value));
return rc;
if (option == TFRC_OPT_RECEIVE_RATE) {
opt_recv->ccid3or_receive_rate = opt_val;
ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
dccp_role(sk), sk, opt_val);
} else {
opt_recv->ccid3or_loss_event_rate = opt_val;
ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
dccp_role(sk), sk, opt_val);
}
}
return 0;
}
static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)

View File

@ -71,9 +71,6 @@ enum ccid3_options {
};
struct ccid3_options_received {
u64 ccid3or_seqno:48,
ccid3or_loss_intervals_idx:16;
u16 ccid3or_loss_intervals_len;
u32 ccid3or_loss_event_rate;
u32 ccid3or_receive_rate;
};