commit b30b9549acaa0ffd4c94c2c50d0756416f9b58ee
author Dave Barach <dave@barachs.net> Mon Jun 22 10:02:25 2020 -0400
committer Florin Coras <florin.coras@gmail.com> Tue Jun 23 15:35:14 2020 +0000
tree 6aa6a41861d1a8383002da298235a992064fd85d
parent cc7209469601a29d0284c50716d876f685868c4b

vlib: debug CLI macro expander, part deux

Deal with circular macro definitions instead of crashing due to stack
overflow.

Separate macro tables, per CLI session

Add documentation to the Sphinx docs

Type: improvement

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I55fc9152bd37ad0c15fa3959f38b07b63100e634

src/vlib/unix/cli.c

diff --git a/src/vlib/unix/cli.c b/src/vlib/unix/cli.c
index 6b02fdf..5979dbd 100644
--- a/src/vlib/unix/cli.c
+++ b/src/vlib/unix/cli.c
@@ -242,6 +242,8 @@
    */
   u8 cursor_direction;
 
+  /** Macro tables for this session */
+  clib_macro_main_t macro_main;
 } unix_cli_file_t;
 
 /** Resets the pager buffer and other data.
@@ -493,7 +495,7 @@
   /** List of new sessions */
   unix_cli_new_session_t *new_sessions;
 
-  /* Macro expander */
+  /** system default macro table */
   clib_macro_main_t macro_main;
 
 } unix_cli_main_t;
@@ -501,6 +503,24 @@
 /** CLI global state */
 static unix_cli_main_t unix_cli_main;
 
+/** Return the macro main / tables we should use for this session
+ */
+static clib_macro_main_t *
+get_macro_main (void)
+{
+  unix_cli_main_t *cm = &unix_cli_main;
+  vlib_main_t *vm = vlib_get_main ();
+  vlib_process_t *cp = vlib_get_current_process (vm);
+  unix_cli_file_t *cf;
+
+  if (pool_is_free_index (cm->cli_file_pool, cp->output_function_arg))
+    return (&cm->macro_main);
+
+  cf = pool_elt_at_index (cm->cli_file_pool, cp->output_function_arg);
+
+  return (&cf->macro_main);
+}
+
 /**
  * @brief Search for a byte sequence in the action list.
  *
@@ -2575,9 +2595,11 @@
       vec_validate (cf->current_command, vec_len (cf->current_command));
       cf->current_command[vec_len (cf->current_command) - 1] = 0;
       /* The macro expander expects proper C-strings, not vectors */
-      expanded = (u8 *) clib_macro_eval (&cm->macro_main,
+      expanded = (u8 *) clib_macro_eval (&cf->macro_main,
 					 (i8 *) cf->current_command,
-					 1 /* complain */ );
+					 1 /* complain */ ,
+					 0 /* level */ ,
+					 8 /* max_level */ );
       /* Macro processor NULL terminates the return */
       _vec_len (expanded) -= 1;
       vec_reset_length (cf->current_command);
@@ -2689,6 +2711,7 @@
   clib_file_del (fm, uf);
 
   unix_cli_file_free (cf);
+  clib_macro_free (&cf->macro_main);
   pool_put (cm->cli_file_pool, cf);
 }
 
@@ -2906,6 +2929,7 @@
 
   pool_get (cm->cli_file_pool, cf);
   clib_memset (cf, 0, sizeof (*cf));
+  clib_macro_init (&cf->macro_main);
 
   template.read_function = unix_cli_read_ready;
   template.write_function = unix_cli_write_ready;
@@ -3962,7 +3986,7 @@
 {
   u8 *macro_name;
   unformat_input_t _line_input, *line_input = &_line_input;
-  unix_cli_main_t *cm = &unix_cli_main;
+  clib_macro_main_t *mm = get_macro_main ();
   clib_error_t *error;
 
   if (!unformat (input, "%s", &macro_name))
@@ -3980,8 +4004,7 @@
     }
   /* the macro expander expects c-strings, not vectors... */
   vec_add1 (line_input->buffer, 0);
-  clib_macro_set_value (&cm->macro_main, (char *) macro_name,
-			(char *) line_input->buffer);
+  clib_macro_set_value (mm, (char *) macro_name, (char *) line_input->buffer);
   vec_free (macro_name);
   unformat_free (line_input);
   return 0;
@@ -4001,12 +4024,12 @@
 		 unformat_input_t * input, vlib_cli_command_t * cmd)
 {
   u8 *macro_name;
-  unix_cli_main_t *cm = &unix_cli_main;
+  clib_macro_main_t *mm = get_macro_main ();
 
   if (!unformat (input, "%s", &macro_name))
     return clib_error_return (0, "missing variable name...");
 
-  if (clib_macro_unset (&cm->macro_main, (char *) macro_name))
+  if (clib_macro_unset (mm, (char *) macro_name))
     vlib_cli_output (vm, "%s wasn't set...", macro_name);
 
   vec_free (macro_name);
@@ -4025,7 +4048,7 @@
 show_macro_cmd_fn (vlib_main_t * vm,
 		   unformat_input_t * input, vlib_cli_command_t * cmd)
 {
-  unix_cli_main_t *cm = &unix_cli_main;
+  clib_macro_main_t *mm = get_macro_main ();
   int evaluate = 1;
 
   if (unformat (input, "noevaluate %=", &evaluate, 0))
@@ -4033,8 +4056,7 @@
   else if (unformat (input, "noeval %=", &evaluate, 0))
     ;
 
-  vlib_cli_output (vm, "%U", format_clib_macro_main, &cm->macro_main,
-		   evaluate);
+  vlib_cli_output (vm, "%U", format_clib_macro_main, mm, evaluate);
   return 0;
 }
 
@@ -4055,6 +4077,7 @@
    * has not been started */
   cm->new_session_process_node_index = ~0;
   clib_macro_init (&cm->macro_main);
+
   return 0;
 }