Re: [PATCH] Allow .load only on suitable file system entries

[Jose E. Marchesi]

             +static char *
             +pk_file_readable (const char *filename)
             +{
             +  static char errmsg[4096];
             +  struct stat statbuf;
             +  if (0 != stat (filename, &statbuf))
             +    {
             +      char *why = strerror (errno);
             +      snprintf (errmsg, 4096, _("Cannot stat %s: %s\n"), 
filename, why);
             +      return errmsg;
             +    }
             +
             +  if (S_ISDIR (statbuf.st_mode))
             +    {
             +      snprintf (errmsg, 4096, _("%s is a directory\n"), filename);
             +      return errmsg;
             +    }
             +
             +  if (access (filename, R_OK) != 0)
             +    {
             +      char *why = strerror (errno);
             +      snprintf (errmsg, 4096, _("%s: file cannot be read: %s\n"),
             +          filename, why);
             +      return errmsg;
             +    }
         
         The stat and check for S_ISDIR can be replaced with:
         
           if (fstat (fileno (stream), &st) == -1 || !S_ISREG (st.st_mode))
             sprintf (errmsg, 4096, _("%s: not a regular file"));
    
    No it can't;  Because we don't have a stream.

    I'm unsure if we want to insist on file being a "regular" file.  For
    example I can envisage a situation where somebody might want to use poke
    to examine (or write!) a filesystem or swapspace on /dev/sd??
    
    Also, if stat fails for any reason (eg the file doesn't exist), then the 
above 
    would give a misleading error message.
    
         
         The check for readability can be done portably using another gnulib
         function, freadable:
         
           if (!freadable (stream))
             sprintf (errmsg, 4096, _("%s: file cannot be read"));
    
    Again, we don't have  a stream at this point, so that isn't going to
    work.
    
Hm ok.  Let's use stat and access instead.
But then, we don't need any additional gnulib module..