Add new SI prefixes R, Q in other places

* lisp/dired-x.el (dired-x--string-to-number, dired-mark-sexp):
* lisp/dired.el (dired-re-inode-size):
* lisp/files.el (directory-listing-before-filename-regexp):
* src/xdisp.c (power_letter):
* src/xdisp.c: Include stdint.h.
Check that the prefixes suffice for ptrdiff_t.

lisp/dired-x.el

@@ -816,7 +816,7 @@ otherwise."
 (defun dired-x--string-to-number (str)
   "Like `string-to-number' but recognize a trailing unit prefix.
 For example, 2K is expanded to 2048.0.  The caller should make
-sure that a trailing letter in STR is one of BKkMGTPEZY."
+sure that a trailing letter in STR is one of BKkMGTPEZYRQ."
   (let* ((val (string-to-number str))
          (u (unless (zerop val)
               (aref str (1- (length str))))))
@@ -831,7 +831,7 @@ sure that a trailing letter in STR is one of BKkMGTPEZY."
       (when (and u (> u ?9))
         (when (= u ?k)
           (setq u ?K))
-        (let ((units '(?B ?K ?M ?G ?T ?P ?E ?Z ?Y)))
+        (let ((units '(?B ?K ?M ?G ?T ?P ?E ?Z ?Y ?R ?Q)))
           (while (and units (/= (pop units) u))
             (setq val (* 1024.0 val)))))
       val)))
@@ -904,7 +904,7 @@ only in the active region if `dired-mark-region' is non-nil."
 	      ;; GNU ls -hs suffixes the block count with a unit and
 	      ;; prints it as a float, FreeBSD does neither.
 	      (dired-re-inode-size "\\=\\s *\\([0-9]+\\s +\\)?\
-\\(?:\\([0-9]+\\(?:\\.[0-9]*\\)?[BkKMGTPEZY]?\\)? ?\\)"))
+\\(?:\\([0-9]+\\(?:\\.[0-9]*\\)?[BkKMGTPEZYRQ]?\\)? ?\\)"))
 	  (beginning-of-line)
 	  (forward-char 2)
 	  (search-forward-regexp dired-re-inode-size nil t)

lisp/dired.el

@@ -530,7 +530,7 @@ The directory name must be absolute, but need not be fully expanded.")
 
 (put 'dired-actual-switches 'safe-local-variable 'dired-safe-switches-p)
 
-(defvar dired-re-inode-size "[0-9 \t]*[.,0-9]*[BkKMGTPEZY]?[ \t]*"
+(defvar dired-re-inode-size "[0-9 \t]*[.,0-9]*[BkKMGTPEZYRQ]?[ \t]*"
   "Regexp for optional initial inode and file size as made by `ls -i -s'.")
 
 ;; These regexps must be tested at beginning-of-line, but are also

lisp/files.el

@@ -7645,7 +7645,7 @@ If DIR's free space cannot be obtained, this function returns nil."
 	 ;; This avoids recognizing `1 may 1997' as a date in the line:
 	 ;; -r--r--r--   1 may      1997        1168 Oct 19 16:49 README
 
-	 ;; The "[BkKMGTPEZY]?" below supports "ls -alh" output.
+	 ;; The "[BkKMGTPEZYRQ]?" below supports "ls -alh" output.
 
 	 ;; For non-iso date formats, we add the ".*" in order to find
 	 ;; the last possible match.  This avoids recognizing
@@ -7657,8 +7657,8 @@ If DIR's free space cannot be obtained, this function returns nil."
          ;; parentheses:
          ;; -rw-r--r-- (modified) 2005-10-22 21:25 files.el
          ;; This is not supported yet.
-    (purecopy (concat "\\([0-9][BkKMGTPEZY]? " iso
-		      "\\|.*[0-9][BkKMGTPEZY]? "
+    (purecopy (concat "\\([0-9][BkKMGTPEZYRQ]? " iso
+		      "\\|.*[0-9][BkKMGTPEZYRQ]? "
 	              "\\(" western "\\|" western-comma
                       "\\|" DD-MMM-YYYY "\\|" east-asian "\\)"
 		      "\\) +")))

src/xdisp.c

@@ -27621,7 +27621,9 @@ static const char power_letter[] =
     'P', /* peta */
     'E', /* exa */
     'Z', /* zetta */
-    'Y'	 /* yotta */
+    'Y', /* yotta */
+    'R', /* ronna */
+    'Q'  /* quetta */
   };
 
 static void