[PATCH] C++ compatibility for some kernel headers

[Sebastian Huber]

We ported the FreeBSD network stack to RTEMS.  Some users want to write
network interface drivers in C++.  It would be nice if we can make some
FreeBSD kernel headers C++ compatible.

sys/buf_ring.h:

Mabye it is better to fix the integer type of br_cons_head to be able to
use it in atomic_cmpset_int().

sys/mbuf.h:

Maybe it is better to fix the integer type of ext_cnt to be able to use
it for uma_find_refcnt().
---
 sys/net/ifq.h      | 16 ++++++++--------
 sys/sys/buf_ring.h |  9 +++++----
 sys/sys/mbuf.h     | 17 +++++++++--------
 3 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/sys/net/ifq.h b/sys/net/ifq.h
index cf0c506..c970443 100644
--- a/sys/net/ifq.h
+++ b/sys/net/ifq.h
@@ -332,7 +332,7 @@ drbr_enqueue(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m)
 }
 
 static __inline void
-drbr_putback(struct ifnet *ifp, struct buf_ring *br, struct mbuf *new)
+drbr_putback(struct ifnet *ifp, struct buf_ring *br, struct mbuf *new_mbuf)
 {
 	/*
 	 * The top of the list needs to be swapped 
@@ -344,11 +344,11 @@ drbr_putback(struct ifnet *ifp, struct buf_ring *br, struct mbuf *new)
 		 * Peek in altq case dequeued it
 		 * so put it back.
 		 */
-		IFQ_DRV_PREPEND(&ifp->if_snd, new);
+		IFQ_DRV_PREPEND(&ifp->if_snd, new_mbuf);
 		return;
 	}
 #endif
-	buf_ring_putback_sc(br, new);
+	buf_ring_putback_sc(br, new_mbuf);
 }
 
 static __inline struct mbuf *
@@ -367,7 +367,7 @@ drbr_peek(struct ifnet *ifp, struct buf_ring *br)
 		return (m);
 	}
 #endif
-	return(buf_ring_peek(br));
+	return ((struct mbuf *)buf_ring_peek(br));
 }
 
 static __inline void
@@ -379,7 +379,7 @@ drbr_flush(struct ifnet *ifp, struct buf_ring *br)
 	if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd))
 		IFQ_PURGE(&ifp->if_snd);
 #endif	
-	while ((m = buf_ring_dequeue_sc(br)) != NULL)
+	while ((m = (struct mbuf *)buf_ring_dequeue_sc(br)) != NULL)
 		m_freem(m);
 }
 
@@ -402,7 +402,7 @@ drbr_dequeue(struct ifnet *ifp, struct buf_ring *br)
 		return (m);
 	}
 #endif
-	return (buf_ring_dequeue_sc(br));
+	return ((struct mbuf *)buf_ring_dequeue_sc(br));
 }
 
 static __inline void
@@ -435,11 +435,11 @@ drbr_dequeue_cond(struct ifnet *ifp, struct buf_ring *br,
 		return (m);
 	}
 #endif
-	m = buf_ring_peek(br);
+	m = (struct mbuf *)buf_ring_peek(br);
 	if (m == NULL || func(m, arg) == 0)
 		return (NULL);
 
-	return (buf_ring_dequeue_sc(br));
+	return ((struct mbuf *)buf_ring_dequeue_sc(br));
 }
 
 static __inline int
diff --git a/sys/sys/buf_ring.h b/sys/sys/buf_ring.h
index a46aa2d..934f1a7 100644
--- a/sys/sys/buf_ring.h
+++ b/sys/sys/buf_ring.h
@@ -86,7 +86,8 @@ buf_ring_enqueue(struct buf_ring *br, void *buf)
 			critical_exit();
 			return (ENOBUFS);
 		}
-	} while (!atomic_cmpset_int(&br->br_prod_head, prod_head, prod_next));
+	} while (!atomic_cmpset_int((volatile int *)&br->br_prod_head,
+	    prod_head, prod_next));
 #ifdef DEBUG_BUFRING
 	if (br->br_ring[prod_head] != NULL)
 		panic("dangling value in enqueue");
@@ -135,7 +136,7 @@ buf_ring_dequeue_mc(struct buf_ring *br)
 			return (NULL);
 		}
 		
-		success = atomic_cmpset_int(&br->br_cons_head, cons_head,
+		success = atomic_cmpset_int((volatile int *)&br->br_cons_head, cons_head,
 		    cons_next);
 	} while (success == 0);		
 
@@ -253,11 +254,11 @@ buf_ring_advance_sc(struct buf_ring *br)
  * the compare and an atomic.
  */
 static __inline void
-buf_ring_putback_sc(struct buf_ring *br, void *new)
+buf_ring_putback_sc(struct buf_ring *br, void *new_item)
 {
 	KASSERT(br->br_cons_head != br->br_prod_tail, 
 		("Buf-Ring has none in putback")) ;
-	br->br_ring[br->br_cons_head] = new;
+	br->br_ring[br->br_cons_head] = new_item;
 }
 
 /*
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index d3e6ce0..960636b 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -627,7 +627,7 @@ m_get(int how, short type)
 
 	args.flags = 0;
 	args.type = type;
-	return (uma_zalloc_arg(zone_mbuf, &args, how));
+	return ((struct mbuf *)uma_zalloc_arg(zone_mbuf, &args, how));
 }
 
 /*
@@ -641,7 +641,7 @@ m_getclr(int how, short type)
 
 	args.flags = 0;
 	args.type = type;
-	m = uma_zalloc_arg(zone_mbuf, &args, how);
+	m = (struct mbuf *)uma_zalloc_arg(zone_mbuf, &args, how);
 	if (m != NULL)
 		bzero(m->m_data, MLEN);
 	return (m);
@@ -654,7 +654,7 @@ m_gethdr(int how, short type)
 
 	args.flags = M_PKTHDR;
 	args.type = type;
-	return (uma_zalloc_arg(zone_mbuf, &args, how));
+	return ((struct mbuf *)uma_zalloc_arg(zone_mbuf, &args, how));
 }
 
 static __inline struct mbuf *
@@ -664,7 +664,7 @@ m_getcl(int how, short type, int flags)
 
 	args.flags = flags;
 	args.type = type;
-	return (uma_zalloc_arg(zone_pack, &args, how));
+	return ((struct mbuf *)uma_zalloc_arg(zone_pack, &args, how));
 }
 
 static __inline void
@@ -703,7 +703,7 @@ m_cljget(struct mbuf *m, int how, int size)
 		m->m_ext.ext_buf = NULL;
 
 	zone = m_getzone(size);
-	return (uma_zalloc_arg(zone, m, how));
+	return ((struct mbuf *)uma_zalloc_arg(zone, m, how));
 }
 
 static __inline void
@@ -736,12 +736,13 @@ m_cljset(struct mbuf *m, void *cl, int type)
 		break;
 	}
 
-	m->m_data = m->m_ext.ext_buf = cl;
-	m->m_ext.ext_free = m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
+	m->m_data = m->m_ext.ext_buf = (caddr_t)cl;
+	m->m_ext.ext_free = NULL;
+	m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
 	m->m_ext.ext_size = size;
 	m->m_ext.ext_type = type;
 	m->m_ext.ext_flags = 0;
-	m->m_ext.ext_cnt = uma_find_refcnt(zone, cl);
+	m->m_ext.ext_cnt = (u_int *)uma_find_refcnt(zone, cl);
 	m->m_flags |= M_EXT;
 
 }
-- 
1.8.4.5