chansrv: fix for deadlock

common/trans.c

@@ -291,6 +291,7 @@ trans_force_write_s(struct trans *self, struct stream *out_s)
     size = (int)(out_s->end - out_s->data);
     total = 0;
 
+    self->in_write = 1;
     while (total < size)
     {
         sent = g_tcp_send(self->sck, out_s->data + total, size - total, 0);
@@ -308,6 +309,7 @@ trans_force_write_s(struct trans *self, struct stream *out_s)
                         {
                             /* term */
                             self->status = TRANS_STATUS_DOWN;
+                            self->in_write = 0;
                             return 1;
                         }
                     }
@@ -317,6 +319,7 @@ trans_force_write_s(struct trans *self, struct stream *out_s)
             {
                 /* error */
                 self->status = TRANS_STATUS_DOWN;
+                self->in_write = 0;
                 return 1;
             }
         }
@@ -324,6 +327,7 @@ trans_force_write_s(struct trans *self, struct stream *out_s)
         {
             /* error */
             self->status = TRANS_STATUS_DOWN;
+            self->in_write = 0;
             return 1;
         }
         else
@@ -331,6 +335,7 @@ trans_force_write_s(struct trans *self, struct stream *out_s)
             total = total + sent;
         }
     }
+    self->in_write = 0;
 
     return 0;
 }
@@ -342,6 +347,84 @@ trans_force_write(struct trans *self)
     return trans_force_write_s(self, self->out_s);
 }
 
+/*****************************************************************************/
+int APP_CC
+trans_write_check(struct trans* self, int timeout)
+{
+    int size;
+    int total;
+    int sent;
+    int error;
+    tbus robjs[1];
+    tbus wobjs[1];
+    struct stream *out_s;
+
+    if (self->status != TRANS_STATUS_UP)
+    {
+        return 1;
+    }
+
+    out_s = self->out_s;
+
+    size = (int)(out_s->end - out_s->data);
+    total = 0;
+
+    self->in_write = 1;
+    while (total < size)
+    {
+        robjs[0] = self->sck;
+        wobjs[0] = self->sck;
+        error = g_obj_wait(robjs, 1, wobjs, 1, timeout);
+        if (error != 0)
+        {
+            /* error */
+            self->status = TRANS_STATUS_DOWN;
+            self->in_write = 0;
+            return 1;
+        }
+
+        if (!g_tcp_can_send(self->sck, 0))
+        {
+            trans_check_wait_objs(self);
+            continue;
+        }
+
+        sent = g_tcp_send(self->sck, out_s->data + total, size - total, 0);
+
+        if (sent == -1)
+        {
+            if (g_tcp_last_error_would_block(self->sck))
+            {
+                if (!g_tcp_can_send(self->sck, 10))
+                {
+                    /* check for term here */
+                }
+            }
+            else
+            {
+                /* error */
+                self->status = TRANS_STATUS_DOWN;
+                self->in_write = 0;
+                return 1;
+            }
+        }
+        else if (sent == 0)
+        {
+            /* error */
+            self->status = TRANS_STATUS_DOWN;
+            self->in_write = 0;
+            return 1;
+        }
+        else
+        {
+            total = total + sent;
+        }
+    }
+    self->in_write = 0;
+
+    return 0;
+}
+
 /*****************************************************************************/
 int APP_CC
 trans_connect(struct trans *self, const char *server, const char *port,

common/trans.h

@@ -54,6 +54,7 @@ struct trans
   struct stream* out_s;
   char* listen_filename;
   tis_term is_term; /* used to test for exit */
+  int in_write;
 };
 
 struct trans* APP_CC
@@ -73,6 +74,8 @@ trans_force_read(struct trans* self, int size);
 int APP_CC
 trans_force_write(struct trans* self);
 int APP_CC
+trans_write_check(struct trans* self, int timeout);
+int APP_CC
 trans_connect(struct trans* self, const char* server, const char* port,
               int timeout);
 int APP_CC

sesman/chansrv/chansrv.c

@@ -293,10 +293,20 @@ send_data_from_chan_item(struct chan_item *chan_item)
     out_uint32_le(s, cod->s->size);
     out_uint8a(s, cod->s->p, size);
     s_mark_end(s);
-    LOGM((LOG_LEVEL_DEBUG, "chansrv::send_channel_data: -- "
+    LOGM((LOG_LEVEL_DEBUG, "chansrv::send_data_from_chan_item: -- "
           "size %d chan_flags 0x%8.8x", size, chan_flags));
     g_sent = 1;
-    error = trans_force_write(g_con_trans);
+    if (g_con_trans->in_write)
+    {
+        g_writeln("chansrv::send_data_from_chan_item: error, "
+                  "write while in_write");
+        error = 1;
+    }
+    else
+    {
+        /* write but check for read if blocked */
+        error = trans_write_check(g_con_trans, -1);
+    }
 
     if (error != 0)
     {