Re: [PATCH] Use non-destructive parsing in pkl_struct_type_traverse

[Jose E. Marchesi]

Hi Tim.

    This removes the need for memory allocations and simplifies code.
    
    2020-04-09  Tim Rühsen  <address@hidden>
    
            * lib/pkl-ast.c (pkl_struct_type_traverse): Use
            non-destructive parsing without memory allocations.

This is OK for master.
Thanks!

    ---
     ChangeLog     |  5 +++++
     lib/pkl-ast.c | 46 ++++++++++++----------------------------------
     2 files changed, 17 insertions(+), 34 deletions(-)
    
    diff --git a/lib/pkl-ast.c b/lib/pkl-ast.c
    index 78e7261a..cacc1aa0 100644
    --- a/lib/pkl-ast.c
    +++ b/lib/pkl-ast.c
    @@ -645,35 +645,24 @@ pkl_ast_dup_type (pkl_ast_node type)
     pkl_ast_node
     pkl_struct_type_traverse (pkl_ast_node type, const char *path)
     {
    -  char *trunk, *sub, *base;
    +  const char *s, *e;
    
       if (PKL_AST_TYPE_CODE (type) != PKL_TYPE_STRUCT)
         return NULL;
    
    -  trunk = strndup (path, strlen (path) - strlen (strrchr (path, '.')));
    -  base = strtok (trunk, ".");
    -
    -  /* Node in the form XX. Check to silence the compiler about base not 
used */
    -  if (base == NULL)
    -    {
    -      free (trunk);
    -      return type;
    -    }
    -
    -  while ((sub = strtok (NULL, ".")) != NULL)
    +  for (s = path, e = s; *e; s = e + 1)
         {
    -      pkl_ast_node ename;
    -      pkl_ast_node etype, t;
    -      char *field;
    +      /* Ignore empty entries and ignore last part */
    +      if ((e = strchrnul (s, ':')) == s || !*e)
    +        continue;
    
    -      etype = NULL;
    -
    -      if (PKL_AST_TYPE_CODE (type) != PKL_TYPE_STRUCT)
    -        goto out;
    -
    -      for (t = PKL_AST_TYPE_S_ELEMS (type); t;
    +      for (pkl_ast_node t = PKL_AST_TYPE_S_ELEMS (type); t;
                t = PKL_AST_CHAIN (t))
             {
    +          pkl_ast_node ename;
    +          pkl_ast_node etype;
    +          const char *field;
    +
               if (PKL_AST_CODE (t) != PKL_AST_STRUCT_TYPE_FIELD)
                 continue;
    
    @@ -682,22 +671,11 @@ pkl_struct_type_traverse (pkl_ast_node type, const 
char *path)
    
               field = PKL_AST_IDENTIFIER_POINTER (ename);
    
    -          if (STREQ (field, sub))
    -            {
    -              type = etype;
    -              break;
    -            }
    +          if (!strncmp (field, s, e - s) && !field[e - s])
    +            return etype;
             }
    -
    -      if (type != etype)
    -        goto out;
         }
    
    -  free (trunk);
    -  return type;
    -
    -out:
    -  free (trunk);
       return NULL;
     }
    
    --
    2.26.0