Re: [PATCH v1 3/7] ldlang.*: process ASCII command

[Jan Beulich <jbeulich@suse.com>]

On 28.06.2024 23:46, binutils@emagii.com wrote:
> --- a/ld/ldlang.c
> +++ b/ld/ldlang.c
> @@ -8663,15 +8663,20 @@ lang_add_data (int type, union etree_union *exp)
>    new_stmt->type = type;
>  }
>  
> -void
> -lang_add_string (const char *s)
> +/* Convert escape codes in S.
> +   Supports \n, \r, \t and \NNN octals.
> +   Returns a copy of S in a malloc'ed buffer.  */
> +
> +static char *
> +convert_string (const char * s)
>  {
> -  bfd_vma  len = strlen (s);
> -  bfd_vma  i;
> -  bool     escape = false;
> +  size_t  len = strlen (s);
> +  size_t  i;
> +  bool    escape = false;
> +  char *  buffer = malloc (len + 1);

You want to avoid crashing if this allocation fails. Perhaps by simply
using xmalloc() or e.g. XNEWVEC().

> +  char *  b;
>  
> -  /* Add byte expressions until end of string.  */
> -  for (i = 0 ; i < len; i++)
> +  for (i = 0, b = buffer; i < len; i++)
>      {
>        char c = *s++;
>  
> @@ -8729,21 +8734,53 @@ lang_add_string (const char *s)
>  	      }
>  	      break;
>  	    }
> -
> -	  lang_add_data (BYTE, exp_intop (c));
>  	  escape = false;
>  	}
>        else
>  	{
>  	  if (c == '\\')
> -	    escape = true;
> -	  else
> -	    lang_add_data (BYTE, exp_intop (c));
> +	    {
> +	      escape = true;
> +	      continue;
> +	    }
>  	}
> +
> +      * b ++ = c;
>      }
>  
> -  /* Remeber to terminate the string.  */
> -  lang_add_data (BYTE, exp_intop (0));
> +  * b = 0;
> +  return buffer;
> +}
> +
> +void
> +lang_add_string (size_t size, const char *s)
> +{
> +  size_t  len;
> +  size_t  i;
> +  char *  string;
> +
> +  string = convert_string (s);
> +  len = strlen (string);
> +
> +  /* Check if it is ASCIZ command (len == 0) */
> +  if (size == 0)
> +    /* Make sure that we include the terminating nul byte.  */
> +    size = len + 1;
> +  else if (len >= size)
> +    {
> +      len = size - 1;
> +
> +      einfo (_("%P:%pS: warning: ASCII string does not fit in allocated space,"
> +		" truncated\n"), NULL);
> +    }
> +
> +  for (i = 0 ; i < len ; i++)

Nit: No blanks before ; please.

Jan