Fixes for issues Coverity has reported (VPP-972)

177117: fstat() returns -1 on error; the code is
        checking for any positive value instead
175142: final return could never be reached; simple
        refactoring
175235,175236: Warning suppressed with an explicit
        cast to (void)
174817: Final return couldn't be reached; is
        is_in_order is 0 then 'rv' is already returned
        above
172095,172093: If is_is_set does not get set to 1,
        then return 0 has already been invoked
174405: Re-kill this (nothing sets rv)
171136: Looks like a cmd line flag to set test_bytes
        was missing; added it, and refactored the
        argc/argv processing to avoid two other
        potential segv's
176813: Add range checking for term width/height.
        First stab at a reasonable range is 1-512
        for both.
175350: Fix implicit casting in shift operation
174272: Not a c+p error; try using a coverity
        annotation to ignore it
174273,175320: Annotated FORWARD_NULL

Change-Id: I58d0f860fc2209f59f8d1b6b344d631b8d429ace
Signed-off-by: Chris Luke <chrisy@flirble.org>

4 files changed, 13 insertions, 39 deletions

diff --git a/src/vnet/mpls/mpls_api.c b/src/vnet/mpls/mpls_api.c
index 988c2c98232..762c40ffa8f 100644
--- a/src/vnet/mpls/mpls_api.c
+++ b/src/vnet/mpls/mpls_api.c
@@ -96,7 +96,7 @@ vl_api_mpls_table_add_del_t_handler (vl_api_mpls_table_add_del_t * mp)
   else
     mpls_table_delete (ntohl (mp->mt_table_id), 1);
 
-  rv = (rv == 0) ? vnm->api_errno : rv;
+  // NB: Nothing sets rv; none of the above returns an error
 
   REPLY_MACRO (VL_API_MPLS_TABLE_ADD_DEL_REPLY);
 }
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 4544f9a0f93..792e6612dc1 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -267,10 +267,7 @@ stream_session_enqueue_data (transport_connection_t * tc, vlib_buffer_t * b,
 	}
     }
 
-  if (is_in_order)
-    return enqueued;
-
-  return 0;
+  return enqueued;
 }
 
 /** Check if we have space in rx fifo to push more bytes */
diff --git a/src/vnet/session/session_cli.c b/src/vnet/session/session_cli.c
index d9f516beab9..8c30a1df7eb 100755
--- a/src/vnet/session/session_cli.c
+++ b/src/vnet/session/session_cli.c
@@ -127,13 +127,8 @@ unformat_stream_session_id (unformat_input_t * input, va_list * args)
       *is_ip4 = 0;
       tuple_is_set = 1;
     }
-  else
-    return 0;
-
-  if (tuple_is_set)
-    return 1;
 
-  return 0;
+  return tuple_is_set;
 }
 
 uword
@@ -144,21 +139,12 @@ unformat_stream_session (unformat_input_t * input, va_list * args)
   u8 proto = ~0;
   ip46_address_t lcl, rmt;
   u32 lcl_port = 0, rmt_port = 0;
-  u8 is_ip4 = 0, s_type = ~0, id_is_set = 0;
+  u8 is_ip4 = 0, s_type = ~0;
 
-  if (unformat (input, "%U", unformat_stream_session_id, &proto, &lcl, &rmt,
-		&lcl_port, &rmt_port, &is_ip4))
-    {
-      id_is_set = 1;
-    }
-  else
+  if (!unformat (input, "%U", unformat_stream_session_id, &proto, &lcl, &rmt,
+		 &lcl_port, &rmt_port, &is_ip4))
     return 0;
 
-  if (!id_is_set)
-    {
-      return 0;
-    }
-
   s_type = session_type_from_proto_and_ip (proto, is_ip4);
   if (is_ip4)
     s = stream_session_lookup4 (&lcl.ip4, &rmt.ip4,
@@ -185,21 +171,12 @@ unformat_transport_connection (unformat_input_t * input, va_list * args)
   u8 proto = ~0;
   ip46_address_t lcl, rmt;
   u32 lcl_port = 0, rmt_port = 0;
-  u8 is_ip4 = 0, s_type = ~0, id_is_set = 0;
+  u8 is_ip4 = 0, s_type = ~0;
 
-  if (unformat (input, "%U", unformat_stream_session_id, &proto, &lcl, &rmt,
-		&lcl_port, &rmt_port, &is_ip4))
-    {
-      id_is_set = 1;
-    }
-  else
+  if (!unformat (input, "%U", unformat_stream_session_id, &proto, &lcl, &rmt,
+		 &lcl_port, &rmt_port, &is_ip4))
     return 0;
 
-  if (!id_is_set)
-    {
-      return 0;
-    }
-
   proto = (proto == (u8) ~ 0) ? suggested_proto : proto;
   if (proto == (u8) ~ 0)
     return 0;
diff --git a/src/vnet/session/session_lookup.c b/src/vnet/session/session_lookup.c
index 0f9abf9aa74..4487b1c305f 100644
--- a/src/vnet/session/session_lookup.c
+++ b/src/vnet/session/session_lookup.c
@@ -233,15 +233,15 @@ stream_session_half_open_table_add (transport_connection_t * tc, u64 value)
     {
       make_v4_ss_kv_from_tc (&kv4, tc);
       kv4.value = value;
-      clib_bihash_add_del_16_8 (&sl->v4_half_open_hash, &kv4,
-				1 /* is_add */ );
+      (void) clib_bihash_add_del_16_8 (&sl->v4_half_open_hash, &kv4,
+				       1 /* is_add */ );
     }
   else
     {
       make_v6_ss_kv_from_tc (&kv6, tc);
       kv6.value = value;
-      clib_bihash_add_del_48_8 (&sl->v6_half_open_hash, &kv6,
-				1 /* is_add */ );
+      (void) clib_bihash_add_del_48_8 (&sl->v6_half_open_hash, &kv6,
+				       1 /* is_add */ );
     }
 }