[Python-Dev] OpenVMS file system and UNIVERSAL_NEWLINES support

[Jean-François Piéronne]

Jack Jansen wrote:
> 
> On 23-feb-04, at 18:15, Jean-François Piéronne wrote:
> 
>> Hi all,
>>
>> I am one of the maintainer of Python on OpenVMS.
>>
>> Building from time to time Python 2.4 from CVS snapshot, I have just 
>> noticed that all the conditional compilation against 
>> WITH_UNIVERSAL_NEWLINES has been removed.
>>
>> This is a major problem on OpenVMS.
> 
> 
> Ah, I was afraid this was going to happen when I saw the checkin message 
> about getting rid of the universal newlines conditional.
> 
> The easiest solution (apart from putting WITH_UNIVERSAL_NEWLINES back 
> in) is to just leave all the universal newlines machinery in place, but 
> disable it. So, where the old situation was that there were ifdefs all 
> over the place the new situation would be that all the code always goes 
> through Py_UniversalNewlineFgets() and Py_UniversalNewlineFread(), but 
> on systems with record-based I/O these just call fgets() and fread(). 
> Then there's only one more ifdef to go: in open_the_file() don't set the 
> mode to "rb" but just plain "r".
> 
> I assume that sockets and other places where WITH_UNIVERSAL_NEWLINES may 
> have been referred to aren't going to be a problem  for you because 
> those aren't applicable to VMS anyway, right?
> -- 
> Jack Jansen, <Jack.Jansen at cwi.nl>, http://www.cwi.nl/~jack
> If I can't dance I don't want to be part of your revolution -- Emma Goldman
> 

thanks for your help,

Before I submit a patch, I have done the following update which seem to fix 
the problem, any comment are welcome.

patch for include/fileobject.h
@@ -54,3 +54,7 @@
  */
+#ifdef __VMS
+#define PY_STDIOTEXTMODE ""
+#else
  #define PY_STDIOTEXTMODE "b"
+#endif
  char *Py_UniversalNewlineFgets(char *, int, FILE*, PyObject *);


patch for objects/fileobject.c
@@ -119,3 +124,7 @@
         f->f_buf = NULL;
+#ifdef __VMS
+       f->f_univ_newline = 0;
+#else
         f->f_univ_newline = (strchr(mode, 'U') != NULL);
+#endif
         f->f_newlinetypes = NEWLINE_UNKNOWN;
@@ -164,3 +173,11 @@
                 if (strcmp(mode, "U") == 0 || strcmp(mode, "rU") == 0)
+#ifdef __VMS
+               /* Compatibility: specifying U in a Python without universal
+               ** newlines is allowed, and the file is opened as a normal text
+               ** file.
+               */
+                       mode = "r";
+#else
                         mode = "rb";
+#endif
  #ifdef MS_WINDOWS

patch for modules/bz2modules.c
@@ -1293,3 +1293,7 @@
                         case 'U':
+#ifdef __VMS
+                               self->f_univ_newline = 0;
+#else
                                 self->f_univ_newline = 1;
+#endif
                                 break;




Cheers,

Jean-François