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Applied cleaner new patch for bug #8708.

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Implemented multiple packets on the outgoing queue in etharp.c.
Removed etharp.c specific queueing functions.
Fixed generic pbuf.c queueing functions.
This commit is contained in:
likewise
2004-04-30 00:25:03 +00:00
parent d31830225c
commit 94d3b04d68
3 changed files with 103 additions and 145 deletions
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50
src/core/pbuf.c
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@@ -11,12 +11,15 @@
* list. This is called a "pbuf chain".
*
* Multiple packets may be queued, also using this singly linked list.
* This is called a "packet queue". So, a packet queue consists of one
* or more pbuf chains, each of which consist of one or more pbufs.
* This is called a "packet queue".
*
* So, a packet queue consists of one or more pbuf chains, each of
* which consist of one or more pbufs. Currently, queues are only
* supported in a limited section of lwIP, this is the etharp queueing
* code. Outside of this section no packet queues are supported yet.
*
* The differences between a pbuf chain and a packet queue are very
* subtle. Currently, queues are only supported in a limited section
* of lwIP, this is the etharp queueing code. Outside of this section
* no packet queues are supported as of yet.
* precise but subtle.
*
* The last pbuf of a packet has a ->tot_len field that equals the
* ->len field. It can be found by traversing the list. If the last
@@ -504,14 +507,14 @@ pbuf_header(struct pbuf *p, s16_t header_size)
}
/**
* Dereference a pbuf (chain) and deallocate any no-longer-used
* pbufs at the head of this chain.
* Dereference a pbuf chain or queue and deallocate any no-longer-used
* pbufs at the head of this chain or queue.
*
* Decrements the pbuf reference count. If it reaches
* zero, the pbuf is deallocated.
*
* For a pbuf chain, this is repeated for each pbuf in the chain,
* up to a pbuf which has a non-zero reference count after
* up to the first pbuf which has a non-zero reference count after
* decrementing. (This might de-allocate the whole chain.)
*
* @param pbuf The pbuf (chain) to be dereferenced.
@@ -542,6 +545,8 @@ pbuf_free(struct pbuf *p)
u8_t count;
SYS_ARCH_DECL_PROTECT(old_level);
LWIP_ASSERT("p != NULL", p != NULL);
/* if assertions are disabled, proceed with debug output */
if (p == NULL) {
LWIP_DEBUGF(PBUF_DEBUG | DBG_TRACE | 2, ("pbuf_free(p == NULL) was called.\n"));
return 0;
@@ -710,9 +715,7 @@ pbuf_queue(struct pbuf *p, struct pbuf *n)
{
LWIP_ASSERT("p != NULL", p != NULL);
LWIP_ASSERT("n != NULL", n != NULL);
if ((p == NULL) || (n == NULL))
return;
if ((p == NULL) || (n == NULL)) return;
/* iterate through all packets on queue */
while (p->next != NULL) {
@@ -720,15 +723,20 @@ pbuf_queue(struct pbuf *p, struct pbuf *n)
#if PBUF_DEBUG
/* iterate through all pbufs in packet */
while (p->tot_len != p->len) {
/* make sure invariant condition holds */
LWIP_ASSERT("p->len < p->tot_len", p->len < p->tot_len);
/* make sure each packet is complete */
LWIP_ASSERT("p->next != NULL", p->next != NULL);
p = p->next;
/* { p->tot_len == p->len } => p is last pbuf of a packet */
}
#endif
/* now p->tot_len == p->len */
/* { p->tot_len == p->len } => p is last pbuf of a packet */
/* proceed to next packet on queue */
p = p->next;
if (p->next != NULL) p = p->next;
}
/* { p->tot_len == p->len and p->next == NULL } ==>
* { p is last pbuf of last packet on queue } */
/* chain last pbuf of queue with n */
p->next = n;
/* n is now referenced to one more time */
@@ -739,6 +747,8 @@ pbuf_queue(struct pbuf *p, struct pbuf *n)
/**
* Remove a packet from the head of a queue.
*
* The caller MUST reference the remainder of the queue (as returned).
*
* @param p pointer to first packet on the queue which will be dequeued.
* @return first packet on the remaining queue (NULL if no further packets).
*
@@ -751,17 +761,25 @@ pbuf_dequeue(struct pbuf *p)
/* iterate through all pbufs in packet */
while (p->tot_len != p->len) {
/* make sure invariant condition holds */
LWIP_ASSERT("p->len < p->tot_len", p->len < p->tot_len);
/* make sure each packet is complete */
LWIP_ASSERT("p->next != NULL", p->next != NULL);
p = p->next;
}
/* { p->tot_len == p->len } => p is the last pbuf of the first packet */
/* remember next packet on queue */
q = p->next;
/* dequeue p from queue */
p->next = NULL;
/* q is now referenced to one less time */
pbuf_free(q);
LWIP_DEBUGF(PBUF_DEBUG | DBG_FRESH | 2, ("pbuf_dequeue: dereferencing remaining queue %p\n", (void *)q));
/* any next packet on queue? */
if (q != NULL) {
/* although q is no longer referenced by p, it MUST be referenced by
* the caller, who is maintaining this packet queue */
LWIP_DEBUGF(PBUF_DEBUG | DBG_FRESH | 2, ("pbuf_dequeue: at least one packet on queue, first %p\n", (void *)q));
} else {
LWIP_DEBUGF(PBUF_DEBUG | DBG_FRESH | 2, ("pbuf_dequeue: no further packets on queue\n"));
}
return q;
}
#endif