Index: Include/fileobject.h
===================================================================
RCS file: /cvsroot/python/python/dist/src/Include/fileobject.h,v
retrieving revision 2.29
diff -c -r2.29 fileobject.h
*** Include/fileobject.h	24 May 2002 15:24:38 -0000	2.29
--- Include/fileobject.h	5 Aug 2002 19:56:51 -0000
***************
*** 13,21 ****
  	PyObject *f_name;
  	PyObject *f_mode;
  	int (*f_close)(FILE *);
! 	int f_softspace; /* Flag used by 'print' command */
! 	int f_binary; /* Flag which indicates whether the file is open
! 			 open in binary (1) or test (0) mode */
  #ifdef WITH_UNIVERSAL_NEWLINES
  	int f_univ_newline;	/* Handle any newline convention */
  	int f_newlinetypes;	/* Types of newlines seen */
--- 13,24 ----
  	PyObject *f_name;
  	PyObject *f_mode;
  	int (*f_close)(FILE *);
! 	int f_softspace;	/* Flag used by 'print' command */
! 	int f_binary;		/* Flag which indicates whether the file is 
! 				   open in binary (1) or text (0) mode */
! 	char* f_buf;		/* Allocated readahead buffer */
! 	char* f_bufend;		/* Points after last occupied position */
! 	char* f_bufptr;		/* Current buffer position */
  #ifdef WITH_UNIVERSAL_NEWLINES
  	int f_univ_newline;	/* Handle any newline convention */
  	int f_newlinetypes;	/* Types of newlines seen */
Index: Objects/fileobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/fileobject.c,v
retrieving revision 2.165
diff -c -r2.165 fileobject.c
*** Objects/fileobject.c	14 Jul 2002 22:14:19 -0000	2.165
--- Objects/fileobject.c	5 Aug 2002 19:56:55 -0000
***************
*** 116,121 ****
--- 116,122 ----
  	f->f_close = close;
  	f->f_softspace = 0;
  	f->f_binary = strchr(mode,'b') != NULL;
+ 	f->f_buf = NULL;
  #ifdef WITH_UNIVERSAL_NEWLINES
  	f->f_univ_newline = (strchr(mode, 'U') != NULL);
  	f->f_newlinetypes = NEWLINE_UNKNOWN;
***************
*** 271,276 ****
--- 272,279 ----
  	return NULL;
  }
  
+ void drop_readahead(PyFileObject *);
+ 
  /* Methods */
  
  static void
***************
*** 283,288 ****
--- 286,292 ----
  	}
  	Py_XDECREF(f->f_name);
  	Py_XDECREF(f->f_mode);
+ 	drop_readahead(f);
  	f->ob_type->tp_free((PyObject *)f);
  }
  
***************
*** 405,410 ****
--- 409,415 ----
  
  	if (f->f_fp == NULL)
  		return err_closed();
+ 	drop_readahead(f);
  	whence = 0;
  	if (!PyArg_ParseTuple(args, "O|i:seek", &offobj, &whence))
  		return NULL;
***************
*** 1620,1628 ****
  static PyObject *
  file_getiter(PyObject *f)
  {
! 	return PyObject_CallMethod(f, "xreadlines", "");
  }
  
  static PyObject *
  file_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
  {
--- 1625,1744 ----
  static PyObject *
  file_getiter(PyObject *f)
  {
! 	Py_INCREF(f);
! 	return f;
! }
! 
! void
! drop_readahead(PyFileObject *f)
! {
! 	if (f->f_buf != NULL) {
! 		PyMem_Free(f->f_buf);
! 		f->f_buf = NULL;
! 	}
! }
! 
! /* Make sure that file has a readahead buffer with at least one byte 
!    (unless at EOF) and no more than bufsize.  Returns negative value on 
!    error */
! int readahead(PyFileObject *f, int bufsize) {
! 	int chunksize;
! 
! 	if (f->f_buf != NULL) {
! 		if( (f->f_bufend - f->f_bufptr) >= 1) 
! 			return 0;
! 		else
! 			drop_readahead(f);
! 	}
! 	if ((f->f_buf = PyMem_Malloc(bufsize)) == NULL) {
! 		return -1;
! 	}
! 	Py_BEGIN_ALLOW_THREADS
! 	errno = 0;
! 	chunksize = Py_UniversalNewlineFread(
! 		f->f_buf, bufsize, f->f_fp, (PyObject *)f);
! 	Py_END_ALLOW_THREADS
! 	if (chunksize == 0) {
! 		if (ferror(f->f_fp)) {
! 			PyErr_SetFromErrno(PyExc_IOError);
! 			clearerr(f->f_fp);
! 			drop_readahead(f);
! 			return -1;
! 		}
! 	}
! 	f->f_bufptr = f->f_buf;
! 	f->f_bufend = f->f_buf + chunksize;
! 	return 0;
! }
! 
! /* Used by file_iternext. The returned string will start with 'skip'
! uninitialized bytes followed by the remainder of the line. Don't be 
! horrified by the recursive call - maximum recursion depth is limited by 
! logarithmic buffer growth to about 50 even when reading a 1gb line. */
! 
! PyStringObject*
! readahead_get_line_skip(PyFileObject *f, int skip, int bufsize) {
! 	PyStringObject* s;
! 	char *bufptr;
! 	char *buf;
! 	int len;
! 
! 	if (f->f_buf == NULL)
! 		if (readahead(f, bufsize)<0) 
! 			return NULL;
! 
! 	len = f->f_bufend - f->f_bufptr;
! 	if (len == 0) 
! 		return (PyStringObject *)
! 			PyString_FromStringAndSize(NULL, skip);
! 	bufptr = memchr(f->f_bufptr, '\n', len);
! 	if (bufptr != NULL) {
! 		bufptr++;			/* Count the '\n' */
! 		len = bufptr - f->f_bufptr;
! 		s = (PyStringObject *)
! 			PyString_FromStringAndSize(NULL, skip+len);
! 		if (s == NULL) 
! 			return NULL;
! 		memcpy(PyString_AS_STRING(s)+skip, f->f_bufptr, len);
! 		f->f_bufptr = bufptr;
! 		if (bufptr == f->f_bufend)
! 			drop_readahead(f);
! 	} else {
! 		bufptr = f->f_bufptr;
! 		buf = f->f_buf;
! 		f->f_buf = NULL; 	/* Force new readahead buffer */
!                 s = readahead_get_line_skip(
! 			f, skip+len, bufsize + (bufsize>>2) );
! 		if (s == NULL) {
! 		        PyMem_Free(buf);
! 			return NULL;
! 		}
! 		memcpy(PyString_AS_STRING(s)+skip, bufptr, len);
! 		PyMem_Free(buf);
! 	}
! 	return s;
! }
! 
! /* A larger buffer size may actually decrease performance. */
! #define READAHEAD_BUFSIZE 8192
! 
! static PyObject *
! file_iternext(PyObject *f)
! {
! 	PyStringObject* l;
! 
! 	int i;
! 	i = ((PyFileObject *)f)->f_softspace;
! 
! 	l = readahead_get_line_skip((PyFileObject *)f, 0, READAHEAD_BUFSIZE);
! 	if (l == NULL || PyString_GET_SIZE(l) == 0) {
! 		Py_XDECREF(l);
! 		return NULL;
! 	}
! 	return (PyObject *)l;
  }
  
+ 
  static PyObject *
  file_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
  {
***************
*** 1743,1749 ****
  	0,					/* tp_richcompare */
  	0,					/* tp_weaklistoffset */
  	file_getiter,				/* tp_iter */
! 	0,					/* tp_iternext */
  	file_methods,				/* tp_methods */
  	file_memberlist,			/* tp_members */
  	file_getsetlist,			/* tp_getset */
--- 1859,1865 ----
  	0,					/* tp_richcompare */
  	0,					/* tp_weaklistoffset */
  	file_getiter,				/* tp_iter */
! 	file_iternext,				/* tp_iternext */
  	file_methods,				/* tp_methods */
  	file_memberlist,			/* tp_members */
  	file_getsetlist,			/* tp_getset */