[PATCH 2/2] Use obstack in ada_encode_1

[Tom Tromey <tromey@adacore.com>]

I'd eventually like to get rid of the GROW_VECT macro; and since I had
already touched ada_encode_1 I decided to start here.  This patch
removes the use of the macro in favor of using an obstack in this
function.

2020-10-02  Tom Tromey  <tromey@adacore.com>

	* ada-lang.c (ada_encode_1): Use an obstack.
---
 gdb/ChangeLog  |  4 ++++
 gdb/ada-lang.c | 26 +++++++-------------------
 2 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 2502d2847b2..dfe9d44959f 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -926,25 +926,17 @@ const struct ada_opname_map ada_opname_table[] = {
 static const char *
 ada_encode_1 (const char *decoded, bool throw_errors)
 {
-  static char *encoding_buffer = NULL;
-  static size_t encoding_buffer_size = 0;
+  static auto_obstack encoding_buffer;
   const char *p;
-  int k;
 
   if (decoded == NULL)
     return NULL;
 
-  GROW_VECT (encoding_buffer, encoding_buffer_size,
-             2 * strlen (decoded) + 10);
-
-  k = 0;
+  encoding_buffer.clear ();
   for (p = decoded; *p != '\0'; p += 1)
     {
       if (*p == '.')
-        {
-          encoding_buffer[k] = encoding_buffer[k + 1] = '_';
-          k += 2;
-        }
+	obstack_grow_str (&encoding_buffer, "__");
       else if (*p == '"')
         {
           const struct ada_opname_map *mapping;
@@ -960,19 +952,15 @@ ada_encode_1 (const char *decoded, bool throw_errors)
 	      else
 		return NULL;
 	    }
-          strcpy (encoding_buffer + k, mapping->encoded);
-          k += strlen (mapping->encoded);
+	  obstack_grow_str (&encoding_buffer, mapping->encoded);
           break;
         }
       else
-        {
-          encoding_buffer[k] = *p;
-          k += 1;
-        }
+	obstack_1grow (&encoding_buffer, *p);
     }
 
-  encoding_buffer[k] = '\0';
-  return encoding_buffer;
+  obstack_1grow (&encoding_buffer, '\0');
+  return (const char *) obstack_finish (&encoding_buffer);
 }
 
 /* The "encoded" form of DECODED, according to GNAT conventions.
-- 
2.26.2