Handle too long commands in Tramp

* lisp/net/tramp-sh.el (tramp-sh-handle-make-symbolic-link)
(tramp-do-file-attributes-with-ls): Send sequence of commands, in
order to not exceed shell command line limit.

* test/automated/tramp-tests.el (tramp--test-darwin-p): Remove.
(tramp--test-utf8): Include Arabic file name, again.

2 files changed, 115 insertions, 111 deletions

diff --git a/lisp/net/tramp-sh.el b/lisp/net/tramp-sh.el
index 1357db0ac42..7ace8864f88 100644
--- a/lisp/net/tramp-sh.el
+++ b/lisp/net/tramp-sh.el
@@ -1100,15 +1100,19 @@ target of the symlink differ."
       ;; Right, they are on the same host, regardless of user, method,
       ;; etc.  We now make the link on the remote machine. This will
       ;; occur as the user that FILENAME belongs to.
-      (tramp-send-command-and-check
-       l
-       (format
-        "cd %s && %s -sf %s %s"
-        (tramp-shell-quote-argument cwd)
-        ln
-        (tramp-shell-quote-argument filename)
-        (tramp-shell-quote-argument l-localname))
-       t))))
+      (and (tramp-send-command-and-check
+            l (format "cd %s" (tramp-shell-quote-argument cwd)))
+           (tramp-send-command-and-check
+            l (format
+               "%s -sf %s %s"
+               ln
+               (tramp-shell-quote-argument filename)
+               ;; The command could exceed PATH_MAX, so we use
+               ;; relative file names.  However, relative file names
+               ;; could start with "-".  `tramp-shell-quote-argument'
+               ;; does not handle this, we must do it ourselves.
+               (tramp-shell-quote-argument
+                (concat "./" (file-name-nondirectory l-localname)))))))))
 
 (defun tramp-sh-handle-file-truename (filename)
   "Like `file-truename' for Tramp files."
@@ -1266,100 +1270,108 @@ target of the symlink differ."
                  res-inode res-filemodes res-numlinks
                  res-uid res-gid res-size res-symlink-target)
     (tramp-message vec 5 "file attributes with ls: %s" localname)
-    (tramp-send-command
-     vec
-     (format "(%s %s || %s -h %s) && %s %s %s %s"
-             (tramp-get-file-exists-command vec)
-             (tramp-shell-quote-argument localname)
-             (tramp-get-test-command vec)
-             (tramp-shell-quote-argument localname)
-             (tramp-get-ls-command vec)
-             (if (eq id-format 'integer) "-ildn" "-ild")
-             ;; On systems which have no quoting style, file names
-             ;; with special characters could fail.
-             (cond
-              ((tramp-get-ls-command-with-quoting-style vec)
-               "--quoting-style=c")
-              ((tramp-get-ls-command-with-w-option vec)
-               "-w")
-              (t ""))
-             (tramp-shell-quote-argument localname)))
-    ;; Parse `ls -l' output ...
-    (with-current-buffer (tramp-get-buffer vec)
-      (when (> (buffer-size) 0)
-        (goto-char (point-min))
-        ;; ... inode
-        (setq res-inode
-              (condition-case err
-                  (read (current-buffer))
-                (invalid-read-syntax
-                 (when (and (equal (cadr err)
-                                   "Integer constant overflow in reader")
-                            (string-match
-                             "^[0-9]+\\([0-9][0-9][0-9][0-9][0-9]\\)\\'"
-                             (car (cddr err))))
-                   (let* ((big (read (substring (car (cddr err)) 0
-                                                (match-beginning 1))))
-                          (small (read (match-string 1 (car (cddr err)))))
-                          (twiddle (/ small 65536)))
-                     (cons (+ big twiddle)
-                           (- small (* twiddle 65536))))))))
-        ;; ... file mode flags
-        (setq res-filemodes (symbol-name (read (current-buffer))))
-        ;; ... number links
-        (setq res-numlinks (read (current-buffer)))
-        ;; ... uid and gid
-        (setq res-uid (read (current-buffer)))
-        (setq res-gid (read (current-buffer)))
-        (if (eq id-format 'integer)
+    ;; We cannot send all three commands combined, it could exceed
+    ;; NAME_MAX or PATH_MAX.  Happened on Mac OS X, for example.
+    (when (or (tramp-send-command-and-check
+               vec
+               (format "%s %s"
+                       (tramp-get-file-exists-command vec)
+                       (tramp-shell-quote-argument localname)))
+              (tramp-send-command-and-check
+               vec
+               (format "%s -h %s"
+                       (tramp-get-test-command vec)
+                       (tramp-shell-quote-argument localname))))
+      (tramp-send-command
+       vec
+       (format "%s %s %s %s"
+               (tramp-get-ls-command vec)
+               (if (eq id-format 'integer) "-ildn" "-ild")
+               ;; On systems which have no quoting style, file names
+               ;; with special characters could fail.
+               (cond
+                ((tramp-get-ls-command-with-quoting-style vec)
+                 "--quoting-style=c")
+                ((tramp-get-ls-command-with-w-option vec)
+                 "-w")
+                (t ""))
+               (tramp-shell-quote-argument localname)))
+      ;; Parse `ls -l' output ...
+      (with-current-buffer (tramp-get-buffer vec)
+        (when (> (buffer-size) 0)
+          (goto-char (point-min))
+          ;; ... inode
+          (setq res-inode
+                (condition-case err
+                    (read (current-buffer))
+                  (invalid-read-syntax
+                   (when (and (equal (cadr err)
+                                     "Integer constant overflow in reader")
+                              (string-match
+                               "^[0-9]+\\([0-9][0-9][0-9][0-9][0-9]\\)\\'"
+                               (car (cddr err))))
+                     (let* ((big (read (substring (car (cddr err)) 0
+                                                  (match-beginning 1))))
+                            (small (read (match-string 1 (car (cddr err)))))
+                            (twiddle (/ small 65536)))
+                       (cons (+ big twiddle)
+                             (- small (* twiddle 65536))))))))
+          ;; ... file mode flags
+          (setq res-filemodes (symbol-name (read (current-buffer))))
+          ;; ... number links
+          (setq res-numlinks (read (current-buffer)))
+          ;; ... uid and gid
+          (setq res-uid (read (current-buffer)))
+          (setq res-gid (read (current-buffer)))
+          (if (eq id-format 'integer)
+              (progn
+                (unless (numberp res-uid) (setq res-uid -1))
+                (unless (numberp res-gid) (setq res-gid -1)))
             (progn
-              (unless (numberp res-uid) (setq res-uid -1))
-              (unless (numberp res-gid) (setq res-gid -1)))
-          (progn
-            (unless (stringp res-uid) (setq res-uid (symbol-name res-uid)))
-            (unless (stringp res-gid) (setq res-gid (symbol-name res-gid)))))
-        ;; ... size
-        (setq res-size (read (current-buffer)))
-        ;; From the file modes, figure out other stuff.
-        (setq symlinkp (eq ?l (aref res-filemodes 0)))
-        (setq dirp (eq ?d (aref res-filemodes 0)))
-        ;; If symlink, find out file name pointed to.
-        (when symlinkp
-          (search-forward "-> ")
-          (setq res-symlink-target
-                (if (tramp-get-ls-command-with-quoting-style vec)
-                    (read (current-buffer))
-                  (buffer-substring (point) (point-at-eol)))))
-        ;; Return data gathered.
-        (list
-         ;; 0. t for directory, string (name linked to) for symbolic
-         ;; link, or nil.
-         (or dirp res-symlink-target)
-         ;; 1. Number of links to file.
-         res-numlinks
-         ;; 2. File uid.
-         res-uid
-         ;; 3. File gid.
-         res-gid
-         ;; 4. Last access time, as a list of integers.  Normally this
-         ;; would be in the same format as `current-time', but the
-         ;; subseconds part is not currently implemented, and (0 0)
-         ;; denotes an unknown time.
-         ;; 5. Last modification time, likewise.
-         ;; 6. Last status change time, likewise.
-         '(0 0) '(0 0) '(0 0)           ;CCC how to find out?
-         ;; 7. Size in bytes (-1, if number is out of range).
-         res-size
-         ;; 8. File modes, as a string of ten letters or dashes as in ls -l.
-         res-filemodes
-         ;; 9. t if file's gid would change if file were deleted and
-         ;; recreated.  Will be set in `tramp-convert-file-attributes'.
-         t
-         ;; 10. Inode number.
-         res-inode
-         ;; 11. Device number.  Will be replaced by a virtual device number.
-         -1
-         )))))
+              (unless (stringp res-uid) (setq res-uid (symbol-name res-uid)))
+              (unless (stringp res-gid) (setq res-gid (symbol-name res-gid)))))
+          ;; ... size
+          (setq res-size (read (current-buffer)))
+          ;; From the file modes, figure out other stuff.
+          (setq symlinkp (eq ?l (aref res-filemodes 0)))
+          (setq dirp (eq ?d (aref res-filemodes 0)))
+          ;; If symlink, find out file name pointed to.
+          (when symlinkp
+            (search-forward "-> ")
+            (setq res-symlink-target
+                  (if (tramp-get-ls-command-with-quoting-style vec)
+                      (read (current-buffer))
+                    (buffer-substring (point) (point-at-eol)))))
+          ;; Return data gathered.
+          (list
+           ;; 0. t for directory, string (name linked to) for symbolic
+           ;; link, or nil.
+           (or dirp res-symlink-target)
+           ;; 1. Number of links to file.
+           res-numlinks
+           ;; 2. File uid.
+           res-uid
+           ;; 3. File gid.
+           res-gid
+           ;; 4. Last access time, as a list of integers.  Normally
+           ;; this would be in the same format as `current-time', but
+           ;; the subseconds part is not currently implemented, and (0
+           ;; 0) denotes an unknown time.
+           ;; 5. Last modification time, likewise.
+           ;; 6. Last status change time, likewise.
+           '(0 0) '(0 0) '(0 0)         ;CCC how to find out?
+           ;; 7. Size in bytes (-1, if number is out of range).
+           res-size
+           ;; 8. File modes, as a string of ten letters or dashes as in ls -l.
+           res-filemodes
+           ;; 9. t if file's gid would change if file were deleted and
+           ;; recreated.  Will be set in `tramp-convert-file-attributes'.
+           t
+           ;; 10. Inode number.
+           res-inode
+           ;; 11. Device number.  Will be replaced by a virtual device number.
+           -1
+           ))))))
 
 (defun tramp-do-file-attributes-with-perl
   (vec localname &optional id-format)
diff --git a/test/automated/tramp-tests.el b/test/automated/tramp-tests.el
index c956f9cd008..915b30f5e08 100644
--- a/test/automated/tramp-tests.el
+++ b/test/automated/tramp-tests.el
@@ -1785,14 +1785,6 @@ Several special characters do not work properly there."
       (file-truename tramp-test-temporary-file-directory) nil
     (string-match "^HP-UX" (tramp-get-connection-property v "uname" ""))))
 
-(defun tramp--test-darwin-p ()
-  "Check, whether the remote host runs Mac OS X.
-Several special characters do not work properly there."
-  ;; We must refill the cache.  `file-truename' does it.
-  (with-parsed-tramp-file-name
-      (file-truename tramp-test-temporary-file-directory) nil
-    (string-match "^Darwin" (tramp-get-connection-property v "uname" ""))))
-
 (defun tramp--test-check-files (&rest files)
   "Run a simple but comprehensive test over every file in FILES."
   ;; We must use `file-truename' for the temporary directory, because
@@ -2046,7 +2038,7 @@ Use the `ls' command."
         (file-name-coding-system 'utf-8))
     (tramp--test-check-files
      (unless (tramp--test-hpux-p) "Γυρίστε το Γαλαξία με Ώτο Στοπ")
-     (unless (or (tramp--test-hpux-p) (tramp--test-darwin-p))
+     (unless (tramp--test-hpux-p)
        "أصبح بوسعك الآن تنزيل نسخة كاملة من موسوعة ويكيبيديا العربية لتصفحها بلا اتصال بالإنترنت")
      "银河系漫游指南系列"
      "Автостопом по гала́ктике")))