[nuttx] branch master updated: net/rpmsg: initialize semaphore count before wait

[xi...@apache.org]

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xiaoxiang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/nuttx.git


The following commit(s) were added to refs/heads/master by this push:
     new 36591af615 net/rpmsg: initialize semaphore count before wait
36591af615 is described below

commit 36591af61594a105b78af259a20a1b385c514c53
Author: chao an <an...@xiaomi.com>
AuthorDate: Mon May 15 14:26:51 2023 +0800

    net/rpmsg: initialize semaphore count before wait
    
    recvmsg() will incorrectly return 0 if the count of sema before waiting is greater than 0,
    This commit will reinitialize the sema count before waiting:
    
    1181 static ssize_t rpmsg_socket_recvmsg(FAR struct socket *psock,
    1182                                     FAR struct msghdr *msg, int flags)
    1183 {
    ...
    1255   ret = net_sem_timedwait(&conn->recvsem,
    1256                       _SO_TIMEOUT(conn->sconn.s_rcvtimeo)); // recvsem.sem_count == 1; return 0
    ...
    1264   if (!conn->recvdata)              // recvdata not consumed; goto else
    1265     {
    1266       ret = conn->recvlen;
    1267     }
    1268   else
    1269     {
    1270       conn->recvdata = NULL;
    1271     }
    ...
    1282   return ret;                        // BUGON! incorrectly return 0 to user
    1283 }
    
    Signed-off-by: chao an <an...@xiaomi.com>
---
 net/rpmsg/rpmsg_sockif.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/rpmsg/rpmsg_sockif.c b/net/rpmsg/rpmsg_sockif.c
index da150f783b..5f54b52c04 100644
--- a/net/rpmsg/rpmsg_sockif.c
+++ b/net/rpmsg/rpmsg_sockif.c
@@ -342,7 +342,7 @@ static int rpmsg_socket_ept_cb(FAR struct rpmsg_endpoint *ept,
                 }
 
               conn->recvdata = NULL;
-              nxsem_post(&conn->recvsem);
+              rpmsg_socket_post(&conn->recvsem);
             }
 
           if (len > 0)
@@ -1249,6 +1249,7 @@ static ssize_t rpmsg_socket_recvmsg(FAR struct socket *psock,
   conn->recvdata = buf;
   conn->recvlen  = len;
 
+  nxsem_reset(&conn->recvsem, 0);
   nxmutex_unlock(&conn->recvlock);
 
   ret = net_sem_timedwait(&conn->recvsem,