(tar-summarize-buffer): Check for end of buffer before extracting substring.

1 files changed, 33 insertions, 33 deletions

diff --git a/lisp/tar-mode.el b/lisp/tar-mode.el
index bddd32a12fa..190c37988b9 100644
--- a/lisp/tar-mode.el
+++ b/lisp/tar-mode.el
@@ -398,40 +398,40 @@ is visible (and the real data of the buffer is hidden)."
          (pos 1)
          (bs (max 1 (- (buffer-size) 1024))) ; always 2+ empty blocks at end.
          (bs100 (max 1 (/ bs 100)))
-        (tokens nil))
+         (tokens nil))
     (while (not (eq tokens 'empty-tar-block))
-      (let* ((hblock (buffer-substring pos (+ pos 512))))
-        (setq tokens (tar-header-block-tokenize hblock))
-        (setq pos (+ pos 512))
-        (message "parsing tar file...%s%%"
-                 ;(/ (* pos 100) bs)   ; this gets round-off lossage
-                 (/ pos bs100)         ; this doesn't
-                 )
-        (if (eq tokens 'empty-tar-block)
-            nil
-          (if (null tokens) (error "premature EOF parsing tar file"))
-          (if (eq (tar-header-link-type tokens) 20)
-              ;; Foo.  There's an extra empty block after these.
-              (setq pos (+ pos 512)))
-          (let ((size (tar-header-size tokens)))
-            (if (< size 0)
-                (error "%s has size %s - corrupted"
-                       (tar-header-name tokens) size))
-            ;
-            ; This is just too slow.  Don't really need it anyway....
-            ;(tar-header-block-check-checksum
-            ;  hblock (tar-header-block-checksum hblock)
-            ;  (tar-header-name tokens))
-            
-            (setq result (cons (make-tar-desc pos tokens) result))
-            
-            (if (and (null (tar-header-link-type tokens))
-                     (> size 0))
-                (setq pos
-                  (+ pos 512 (ash (ash (1- size) -9) 9))        ; this works
-                  ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't
-                  ))
-            ))))
+      (if (> (+ pos 512) (point-max))
+          (error "premature EOF parsing tar file"))
+      (setq tokens
+            (tar-header-block-tokenize (buffer-substring pos (+ pos 512))))
+      (setq pos (+ pos 512))
+      (message "parsing tar file...%d%%"
+               ;(/ (* pos 100) bs)   ; this gets round-off lossage
+               (/ pos bs100)         ; this doesn't
+               )
+      (if (eq tokens 'empty-tar-block)
+          nil
+        (if (eq (tar-header-link-type tokens) 20)
+            ;; Foo.  There's an extra empty block after these.
+            (setq pos (+ pos 512)))
+        (let ((size (tar-header-size tokens)))
+          (if (< size 0)
+              (error "%s has size %s - corrupted"
+                     (tar-header-name tokens) size))
+          ;
+          ; This is just too slow.  Don't really need it anyway....
+          ;(tar-header-block-check-checksum
+          ;  hblock (tar-header-block-checksum hblock)
+          ;  (tar-header-name tokens))
+
+          (setq result (cons (make-tar-desc pos tokens) result))
+
+          (and (null (tar-header-link-type tokens))
+               (> size 0)
+               (setq pos
+                     (+ pos 512 (ash (ash (1- size) -9) 9))        ; this works
+                     ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't
+                     )))))
     (make-local-variable 'tar-parse-info)
     (setq tar-parse-info (nreverse result)))
   (save-excursion