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|
--- txw.c 2010-08-05 11:07:09.000000000 +0800
+++ txw.c89 2010-08-05 11:11:36.000000000 +0800
@@ -192,7 +192,7 @@
pgm_assert_cmpuint (rs_k, >, 0);
}
- pgm_debug ("create (tsi:%s max-tpdu:%" PRIu16 " sqns:%" PRIu32 " secs %u max-rte %zd use-fec:%s rs(n):%u rs(k):%u)",
+ pgm_debug ("create (tsi:%s max-tpdu:%" PRIu16 " sqns:%" PRIu32 " secs %u max-rte %ld use-fec:%s rs(n):%u rs(k):%u)",
pgm_tsi_print (tsi),
tpdu_size, sqns, secs, max_rte,
use_fec ? "YES" : "NO",
@@ -200,6 +200,7 @@
/* calculate transmit window parameters */
pgm_assert (sqns || (tpdu_size && secs && max_rte));
+ {
const unsigned alloc_sqns = sqns ? sqns : ( (secs * max_rte) / tpdu_size );
window = pgm_malloc0 (sizeof(pgm_txw_t) + ( alloc_sqns * sizeof(struct pgm_sk_buff_t*) ));
window->tsi = tsi;
@@ -231,6 +232,7 @@
pgm_assert (!pgm_txw_retransmit_can_peek (window));
return window;
+ }
}
/* destructor for transmit window. must not be called more than once for same window.
@@ -316,6 +318,7 @@
skb->sequence = window->lead;
/* add skb to window */
+ {
const uint_fast32_t index_ = skb->sequence % pgm_txw_max_length (window);
window->pdata[index_] = skb;
@@ -325,6 +328,7 @@
/* post-conditions */
pgm_assert_cmpuint (pgm_txw_length (window), >, 0);
pgm_assert_cmpuint (pgm_txw_length (window), <=, pgm_txw_max_length (window));
+ }
}
/* peek an entry from the window for retransmission.
@@ -452,6 +456,7 @@
pgm_assert (NULL != window);
pgm_assert_cmpuint (tg_sqn_shift, <, 8 * sizeof(uint32_t));
+ {
const uint32_t tg_sqn_mask = 0xffffffff << tg_sqn_shift;
const uint32_t nak_tg_sqn = sequence & tg_sqn_mask; /* left unshifted */
const uint32_t nak_pkt_cnt = sequence & ~tg_sqn_mask;
@@ -490,6 +495,7 @@
pgm_assert (!pgm_queue_is_empty (&window->retransmit_queue));
state->waiting_retransmit = 1;
return TRUE;
+ }
}
static
@@ -548,14 +554,17 @@
pgm_debug ("retransmit_try_peek (window:%p)", (const void*)window);
/* no lock required to detect presence of a request */
+ {
pgm_list_t* tail_link = pgm_queue_peek_tail_link (&window->retransmit_queue);
if (PGM_UNLIKELY(NULL == tail_link)) {
pgm_debug ("retransmit queue empty on peek.");
return NULL;
}
+ {
struct pgm_sk_buff_t* skb = (struct pgm_sk_buff_t*)tail_link;
pgm_assert (pgm_skb_is_valid (skb));
+ {
pgm_txw_state_t* state = (pgm_txw_state_t*)&skb->cb;
if (!state->waiting_retransmit) {
@@ -572,14 +581,17 @@
}
/* generate parity packet to satisify request */
+ {
const uint8_t rs_h = state->pkt_cnt_sent % (window->rs.n - window->rs.k);
const uint32_t tg_sqn_mask = 0xffffffff << window->tg_sqn_shift;
const uint32_t tg_sqn = skb->sequence & tg_sqn_mask;
bool is_var_pktlen = FALSE;
bool is_op_encoded = FALSE;
uint16_t parity_length = 0;
- const pgm_gf8_t* src[ window->rs.k ];
- for (uint_fast8_t i = 0; i < window->rs.k; i++)
+ const pgm_gf8_t** src = pgm_newa (pgm_gf8_t*, window->rs.k);
+ {
+ uint_fast8_t i;
+ for (i = 0; i < window->rs.k; i++)
{
const struct pgm_sk_buff_t* odata_skb = pgm_txw_peek (window, tg_sqn + i);
const uint16_t odata_tsdu_length = ntohs (odata_skb->pgm_header->pgm_tsdu_length);
@@ -599,6 +611,7 @@
is_op_encoded = TRUE;
}
}
+ }
/* construct basic PGM header to be completed by send_rdata() */
skb = window->parity_buffer;
@@ -618,7 +631,9 @@
{
skb->pgm_header->pgm_options |= PGM_OPT_VAR_PKTLEN;
- for (uint_fast8_t i = 0; i < window->rs.k; i++)
+ {
+ uint_fast8_t i;
+ for (i = 0; i < window->rs.k; i++)
{
struct pgm_sk_buff_t* odata_skb = pgm_txw_peek (window, tg_sqn + i);
const uint16_t odata_tsdu_length = ntohs (odata_skb->pgm_header->pgm_tsdu_length);
@@ -632,6 +647,7 @@
odata_skb->zero_padded = 1;
}
}
+ }
parity_length += 2;
}
@@ -642,6 +658,7 @@
skb->pgm_data->data_sqn = htonl ( tg_sqn | rs_h );
+ {
void* data_bytes = skb->pgm_data + 1;
/* encode every option separately, currently only one applies: opt_fragment
@@ -650,11 +667,14 @@
{
skb->pgm_header->pgm_options |= PGM_OPT_PRESENT;
+ {
struct pgm_opt_fragment null_opt_fragment;
- const pgm_gf8_t* opt_src[ window->rs.k ];
+ const pgm_gf8_t** opt_src = pgm_newa (pgm_gf8_t*, window->rs.k);
memset (&null_opt_fragment, 0, sizeof(null_opt_fragment));
*(uint8_t*)&null_opt_fragment |= PGM_OP_ENCODED_NULL;
- for (uint_fast8_t i = 0; i < window->rs.k; i++)
+ {
+ uint_fast8_t i;
+ for (i = 0; i < window->rs.k; i++)
{
const struct pgm_sk_buff_t* odata_skb = pgm_txw_peek (window, tg_sqn + i);
@@ -669,8 +689,10 @@
opt_src[i] = (pgm_gf8_t*)&null_opt_fragment;
}
}
+ }
/* add options to this rdata packet */
+ {
const uint16_t opt_total_length = sizeof(struct pgm_opt_length) +
sizeof(struct pgm_opt_header) +
sizeof(struct pgm_opt_fragment);
@@ -678,14 +700,17 @@
/* add space for PGM options */
pgm_skb_put (skb, opt_total_length);
+ {
struct pgm_opt_length* opt_len = data_bytes;
opt_len->opt_type = PGM_OPT_LENGTH;
opt_len->opt_length = sizeof(struct pgm_opt_length);
opt_len->opt_total_length = htons ( opt_total_length );
+ {
struct pgm_opt_header* opt_header = (struct pgm_opt_header*)(opt_len + 1);
opt_header->opt_type = PGM_OPT_FRAGMENT | PGM_OPT_END;
opt_header->opt_length = sizeof(struct pgm_opt_header) + sizeof(struct pgm_opt_fragment);
opt_header->opt_reserved = PGM_OP_ENCODED;
+ {
struct pgm_opt_fragment* opt_fragment = (struct pgm_opt_fragment*)(opt_header + 1);
/* The cast below is the correct way to handle the problem.
@@ -700,6 +725,11 @@
sizeof(struct pgm_opt_fragment) - sizeof(struct pgm_opt_header));
data_bytes = opt_fragment + 1;
+ }
+ }
+ }
+ }
+ }
}
/* encode payload */
@@ -710,9 +740,16 @@
parity_length);
/* calculate partial checksum */
+ {
const uint16_t tsdu_length = ntohs (skb->pgm_header->pgm_tsdu_length);
state->unfolded_checksum = pgm_csum_partial ((char*)skb->tail - tsdu_length, tsdu_length, 0);
return skb;
+ }
+ }
+ }
+ }
+ }
+ }
}
/* remove head entry from retransmit queue, will fail on assertion if queue is empty.
@@ -733,6 +770,7 @@
(const void*)window);
/* tail link is valid without lock */
+ {
pgm_list_t* tail_link = pgm_queue_peek_tail_link (&window->retransmit_queue);
/* link must be valid for pop */
@@ -762,6 +800,7 @@
pgm_queue_pop_tail_link (&window->retransmit_queue);
state->waiting_retransmit = 0;
}
+ }
}
/* eof */
|
