bug#1523: [Ivan Shmakov] process-send-string apparently mangles \r into \n

[richardeng]

Sven Joachim wrote:
> I received the following report via the Debian bug tracking system.
> It is reproducible in the trunk.
>
>   
>
> ------------------------------------------------------------------------
>
> Subject:
> Bug#508300: process-send-string apparently mangles \r into \n
> From:
> Ivan Shmakov <oneingray@gmail.com>
> Date:
> Wed, 10 Dec 2008 01:14:09 +0600
> To:
> submit@bugs.debian.org
>
> To:
> submit@bugs.debian.org
> CC:
> Ivan Shmakov <oneingray@gmail.com>
>
>
> Package: emacs22
> Version: 22.2+2-5
>
>         After running the following program:
>
> (let* ((coding-system-for-read  'binary)
>        (coding-system-for-write 'binary)
>        (p (start-process "foo" "*foo*" "od" "-td1")))
>     (process-send-string p "\r\n")
>     (process-send-eof p))
> ;; => #<process foo>
>
>         the `*foo*' buffer contains:
>
> --cut: *foo*--
> 0000000   10   10
> 0000002
>
> Process foo finished
> --cut: *foo*--
>
>         While I'd expect the following instead:
>
> --cut: *foo*--
> 0000000   13   10
> 0000002
>
> Process foo finished
> --cut: *foo*--
>
>         Compare:
>
> (let ((coding-system-for-read  'binary)
>       (coding-system-for-write 'binary))
>   (save-excursion
>     (set-buffer "*foo*")
>     (let* ((start (point))
>            (end   (progn (insert "\r\n") (point))))
>       (call-process-region start end "od" t t t "-td1"))))
>
> --cut: *foo*--
> 0000000   13   10
> 0000002
> --cut: *foo*--
>
>
>   
(start-process "foo" "*foo*" "od" "-td1")             // pty is used, 
pty driver will map '\r' <-> '\n'
(call-process-region start end "od" t t t "-td1")    // temp file is 
used, no such problem

--- process.c.~1.577.~  2009-01-03 07:03:59.000000000 
-0800                                                   
+++ process.c   2009-01-13 01:18:08.000000000 
-0800                                                           
@@ -1871,6 +1871,13 @@
      forkin = forkout = 
-1;                                                                                  

#endif /* not USG, or USG_SUBTTY_WORKS 
*/                                                                    
      pty_flag = 
1;                                                                                           

+      
{                                                                                                       

+       struct emacs_tty 
settings;                                                                             

+       EMACS_GET_TTY(outchannel, 
&settings);                                                                  

+       settings.main.c_iflag &= ~ICRNL;        /* Disable map of CR to 
NL on input */                        
+       settings.main.c_iflag &= ~INLCR;        /* Disable map of NL to 
CR on input */                        
+       EMACS_SET_TTY(outchannel, &settings, 
1);                                                              
+      
}                                                                                                       

    
}                                                                                                         

  
else                                                                                                        

#endif /* HAVE_PTYS */