vppinfra: make _vec_len() read-only

Use of _vec_len() to set vector length breaks address sanitizer.
Users should use vec_set_len(), vec_inc_len(), vec_dec_len () instead.

Type: improvement
Change-Id: I441ae948771eb21c23a61f3ff9163bdad74a2cb8
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vlib/unix/cli.c b/src/vlib/unix/cli.c
index c546948..244c8df 100644
--- a/src/vlib/unix/cli.c
+++ b/src/vlib/unix/cli.c
@@ -1610,7 +1610,7 @@
 
       /* Delete the desired text from the command */
       memmove (cf->current_command, cf->current_command + j, delta);
-      _vec_len (cf->current_command) = delta;
+      vec_set_len (cf->current_command, delta);
 
       /* Print the new contents */
       unix_vlib_cli_output_cooked (cf, uf, cf->current_command, delta);
@@ -1635,7 +1635,7 @@
 	unix_vlib_cli_output_cursor_left (cf, uf);
 
       /* Truncate the line at the cursor */
-      _vec_len (cf->current_command) = cf->cursor;
+      vec_set_len (cf->current_command, cf->cursor);
 
       cf->search_mode = 0;
       break;
@@ -1677,7 +1677,7 @@
 		unix_vlib_cli_output_cooked (cf, uf, (u8 *) " ", 1);
 	      for (; (cf->current_command + cf->cursor) > save; cf->cursor--)
 		unix_vlib_cli_output_cursor_left (cf, uf);
-	      _vec_len (cf->current_command) -= delta;
+	      vec_dec_len (cf->current_command, delta);
 	    }
 	}
       cf->search_mode = 0;
@@ -1734,13 +1734,13 @@
 	  if (cf->excursion == vec_len (cf->command_history))
 	    {
 	      /* down-arrowed to last entry - want a blank line */
-	      _vec_len (cf->current_command) = 0;
+	      vec_set_len (cf->current_command, 0);
 	    }
 	  else if (cf->excursion < 0)
 	    {
 	      /* up-arrowed over the start to the end, want a blank line */
 	      cf->excursion = vec_len (cf->command_history);
-	      _vec_len (cf->current_command) = 0;
+	      vec_set_len (cf->current_command, 0);
 	    }
 	  else
 	    {
@@ -1753,7 +1753,7 @@
 	      vec_validate (cf->current_command, vec_len (prev) - 1);
 
 	      clib_memcpy (cf->current_command, prev, vec_len (prev));
-	      _vec_len (cf->current_command) = vec_len (prev);
+	      vec_set_len (cf->current_command, vec_len (prev));
 	      unix_vlib_cli_output_cooked (cf, uf, cf->current_command,
 					   vec_len (cf->current_command));
 	    }
@@ -1840,7 +1840,7 @@
 	      cf->cursor++;
 	      unix_vlib_cli_output_cursor_left (cf, uf);
 	      cf->cursor--;
-	      _vec_len (cf->current_command)--;
+	      vec_dec_len (cf->current_command, 1);
 	    }
 	  else if (cf->cursor > 0)
 	    {
@@ -1848,7 +1848,7 @@
 	      j = vec_len (cf->current_command) - cf->cursor;
 	      memmove (cf->current_command + cf->cursor - 1,
 		       cf->current_command + cf->cursor, j);
-	      _vec_len (cf->current_command)--;
+	      vec_dec_len (cf->current_command, 1);
 
 	      /* redraw the rest of the line */
 	      unix_vlib_cli_output_cursor_left (cf, uf);
@@ -1884,7 +1884,7 @@
 	      j = vec_len (cf->current_command) - cf->cursor - 1;
 	      memmove (cf->current_command + cf->cursor,
 		       cf->current_command + cf->cursor + 1, j);
-	      _vec_len (cf->current_command)--;
+	      vec_dec_len (cf->current_command, 1);
 	      /* redraw the rest of the line */
 	      unix_vlib_cli_output_cooked (cf, uf,
 					   cf->current_command + cf->cursor,
@@ -1956,7 +1956,7 @@
 	      vec_resize (save, vec_len (cf->current_command) - cf->cursor);
 	      clib_memcpy (save, cf->current_command + cf->cursor,
 			   vec_len (cf->current_command) - cf->cursor);
-	      _vec_len (cf->current_command) = cf->cursor;
+	      vec_set_len (cf->current_command, cf->cursor);
 	    }
 	  else
 	    {
@@ -1978,7 +1978,7 @@
 	      cf->cursor--;
 	      j--;
 	    }
-	  _vec_len (cf->current_command) = j;
+	  vec_set_len (cf->current_command, j);
 
 	  /* replace it with the newly expanded command */
 	  vec_append (cf->current_command, completed);
@@ -2385,7 +2385,7 @@
 
 	      vec_validate (cf->current_command, vec_len (item) - 1);
 	      clib_memcpy (cf->current_command, item, vec_len (item));
-	      _vec_len (cf->current_command) = vec_len (item);
+	      vec_set_len (cf->current_command, vec_len (item));
 
 	      unix_vlib_cli_output_cooked (cf, uf, cf->current_command,
 					   vec_len (cf->current_command));
@@ -2599,7 +2599,7 @@
 					 0 /* level */ ,
 					 8 /* max_level */ );
       /* Macro processor NULL terminates the return */
-      _vec_len (expanded) -= 1;
+      vec_dec_len (expanded, 1);
       vec_reset_length (cf->current_command);
       vec_append (cf->current_command, expanded);
       vec_free (expanded);
@@ -2754,7 +2754,7 @@
 	}
 
       if (data)
-	_vec_len (data) = 0;
+	vec_set_len (data, 0);
     }
 
 done:
@@ -2836,7 +2836,7 @@
 	return clib_error_return_unix (0, "read");
 
       n_read = n < 0 ? 0 : n;
-      _vec_len (cf->input_vector) = l + n_read;
+      vec_set_len (cf->input_vector, l + n_read);
     }
 
   if (!(n < 0))
@@ -2918,7 +2918,7 @@
       vec_free (old_name);
 
       vlib_node_set_state (vm, n->index, VLIB_NODE_STATE_POLLING);
-      _vec_len (cm->unused_cli_process_node_indices) = l - 1;
+      vec_set_len (cm->unused_cli_process_node_indices, l - 1);
     }
   else
     {
@@ -2954,7 +2954,7 @@
   cf->output_vector = 0;
   cf->input_vector = 0;
   vec_validate (cf->current_command, 0);
-  _vec_len (cf->current_command) = 0;
+  vec_set_len (cf->current_command, 0);
 
   vlib_start_process (vm, n->runtime_index);
 
@@ -3445,7 +3445,7 @@
 					 0 /* level */ ,
 					 8 /* max_level */ );
       /* Macro processor NULL terminates the return */
-      _vec_len (expanded) -= 1;
+      vec_dec_len (expanded, 1);
       vec_reset_length (sub_input.buffer);
       vec_append (sub_input.buffer, expanded);
       vec_free (expanded);
diff --git a/src/vlib/unix/main.c b/src/vlib/unix/main.c
index 0b73597..3710d8e 100644
--- a/src/vlib/unix/main.c
+++ b/src/vlib/unix/main.c
@@ -316,7 +316,7 @@
 	  n = read (fd, buf + l, 4096);
 	  if (n > 0)
 	    {
-	      _vec_len (buf) = l + n;
+	      vec_set_len (buf, l + n);
 	      if (n < 4096)
 		break;
 	    }
diff --git a/src/vlib/unix/mc_socket.c b/src/vlib/unix/mc_socket.c
index 9800b1e..1f3b4e9 100644
--- a/src/vlib/unix/mc_socket.c
+++ b/src/vlib/unix/mc_socket.c
@@ -90,7 +90,7 @@
   h.msg_namelen = sizeof (tx_addr[0]);
 
   if (msm->iovecs)
-    _vec_len (msm->iovecs) = 0;
+    vec_set_len (msm->iovecs, 0);
 
   n_bytes = append_buffer_index_to_iovec (vm, buffer_index, &msm->iovecs);
   ASSERT (n_bytes <= msm->mc_main.transport.max_packet_size);
@@ -177,7 +177,7 @@
       vec_validate (msm->rx_buffers, max_alloc - 1);
       n_alloc =
 	vlib_buffer_alloc (vm, msm->rx_buffers + n_left, max_alloc - n_left);
-      _vec_len (msm->rx_buffers) = n_left + n_alloc;
+      vec_set_len (msm->rx_buffers, n_left + n_alloc);
     }
 
   ASSERT (vec_len (msm->rx_buffers) >= n_mtu);
@@ -192,7 +192,7 @@
       msm->iovecs[i].iov_base = b->data;
       msm->iovecs[i].iov_len = buffer_size;
     }
-  _vec_len (msm->iovecs) = n_mtu;
+  vec_set_len (msm->iovecs, n_mtu);
 
   {
     struct msghdr h;
@@ -237,7 +237,7 @@
       b->next_buffer = msm->rx_buffers[i_rx];
     }
 
-  _vec_len (msm->rx_buffers) = i_rx;
+  vec_set_len (msm->rx_buffers, i_rx);
 
   return 0 /* no error */ ;
 }
@@ -418,7 +418,7 @@
 	}
     }
 
-  _vec_len (c->input_vector) = l + n;
+  vec_set_len (c->input_vector, l + n);
 
   if (is_eof && vec_len (c->input_vector) > 0)
     {
@@ -426,7 +426,7 @@
 	{
 	  mc_msg_catchup_request_handler (mcm, (void *) c->input_vector,
 					  c - msm->catchups);
-	  _vec_len (c->input_vector) = 0;
+	  vec_set_len (c->input_vector, 0);
 	}
       else
 	{
diff --git a/src/vlib/unix/util.c b/src/vlib/unix/util.c
index 03aef36..04cd6f5 100644
--- a/src/vlib/unix/util.c
+++ b/src/vlib/unix/util.c
@@ -86,8 +86,8 @@
       s = format (s, "%s/%s", dir_name, e->d_name);
       t = format (t, "%s", e->d_name);
       error = f (arg, s, t);
-      _vec_len (s) = 0;
-      _vec_len (t) = 0;
+      vec_set_len (s, 0);
+      vec_set_len (t, 0);
 
       if (error)
 	break;
@@ -116,7 +116,7 @@
 	      error = clib_error_return_unix (0, "mkdir '%s'", c);
 	      goto done;
 	    }
-	  _vec_len (c)--;
+	  vec_dec_len (c, 1);
 	}
       vec_add1 (c, path[i]);
       i++;