vlib: add recursive macro expander to debug cli

All of the pieces have been sitting around for years.

Added several debug CLI commands:

"define <variable-name> <value>"
"undefine <variable-name>"
"show macro [noeval]"
"echo <whatever>"

Macros may refer to other macros. To defer evaluation:
"define foo \$(bar)" or some such.

The macro evaluator is not smart about "define foo \$(foo)" or more
complicated circular definitions, so don't do that.

Environment variables are available, simply use $<name-of-environment-vbl>

The macro expander has a table of (overrideable) builtin names, which
are evaluated by calling functions.

Simple example:

echo $USER
define ip1 192.168.1.1/24
define ip2 192.168.2.1/24

loop create
loop create
set int ip address loop0 $ip1
set int ip address loop1 $ip2
show int addr
show macro
undefine ip1
undefine ip2

Type: feature

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I08a800647bac573d8ae3cfd75c40061d41c5f976

2 files changed, 3 insertions, 3 deletions

diff --git a/src/vat/main.c b/src/vat/main.c
index 139594944d2..a6779c591ce 100644
--- a/src/vat/main.c
+++ b/src/vat/main.c
@@ -208,14 +208,14 @@ init_error_string_table (vat_main_t * vam)
 }
 
 static i8 *
-eval_current_file (macro_main_t * mm, i32 complain)
+eval_current_file (clib_macro_main_t * mm, i32 complain)
 {
   vat_main_t *vam = &vat_main;
   return ((i8 *) format (0, "%s%c", vam->current_file, 0));
 }
 
 static i8 *
-eval_current_line (macro_main_t * mm, i32 complain)
+eval_current_line (clib_macro_main_t * mm, i32 complain)
 {
   vat_main_t *vam = &vat_main;
   return ((i8 *) format (0, "%d%c", vam->input_line_number, 0));
diff --git a/src/vat/vat.h b/src/vat/vat.h
index bcaddfe0126..3e9476f0a66 100644
--- a/src/vat/vat.h
+++ b/src/vat/vat.h
@@ -158,7 +158,7 @@ typedef struct
   uword *help_by_name;
 
   /* macro table */
-  macro_main_t macro_main;
+  clib_macro_main_t macro_main;
 
   /* Errors by number */
   uword *error_string_by_error_number;