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Merged revisions 88486 via svnmerge from 

svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r88486 | antoine.pitrou | 2011-02-22 00:41:12 +0100 (mar., 22 févr. 2011) | 5 lines

  Issue #4681: Allow mmap() to work on file sizes and offsets larger than
  4GB, even on 32-bit builds.  Initial patch by Ross Lagerwall, adapted for
  32-bit Windows.
........
This commit is contained in:
Antoine Pitrou 2011-02-21 23:59:20 +00:00
parent e6cc7d6427
commit f4d2b3dc10
3 changed files with 121 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
Lib/test/test_mmap.py
View File

@ -1,6 +1,6 @@
from test.test_support import TESTFN, run_unittest, import_module
from test.test_support import TESTFN, run_unittest, import_module, unlink, requires
import unittest
import os, re, itertools, socket
import os, re, itertools, socket, sys
mmap = import_module('mmap')
@ -627,8 +627,63 @@ class MmapTests(unittest.TestCase):
finally:
s.close()
class LargeMmapTests(unittest.TestCase):
def setUp(self):
unlink(TESTFN)
def tearDown(self):
unlink(TESTFN)
def _working_largefile(self):
# Only run if the current filesystem supports large files.
f = open(TESTFN, 'wb', buffering=0)
try:
f.seek(0x80000001)
f.write(b'x')
f.flush()
except (IOError, OverflowError):
raise unittest.SkipTest("filesystem does not have largefile support")
finally:
f.close()
unlink(TESTFN)
def test_large_offset(self):
if sys.platform[:3] == 'win' or sys.platform == 'darwin':
requires('largefile',
'test requires %s bytes and a long time to run' % str(0x180000000))
self._working_largefile()
with open(TESTFN, 'wb') as f:
f.seek(0x14FFFFFFF)
f.write(b" ")
with open(TESTFN, 'rb') as f:
m = mmap.mmap(f.fileno(), 0, offset=0x140000000, access=mmap.ACCESS_READ)
try:
self.assertEqual(m[0xFFFFFFF], b" ")
finally:
m.close()
def test_large_filesize(self):
if sys.platform[:3] == 'win' or sys.platform == 'darwin':
requires('largefile',
'test requires %s bytes and a long time to run' % str(0x180000000))
self._working_largefile()
with open(TESTFN, 'wb') as f:
f.seek(0x17FFFFFFF)
f.write(b" ")
with open(TESTFN, 'rb') as f:
m = mmap.mmap(f.fileno(), 0x10000, access=mmap.ACCESS_READ)
try:
self.assertEqual(m.size(), 0x180000000)
finally:
m.close()
def test_main():
run_unittest(MmapTests)
run_unittest(MmapTests, LargeMmapTests)
if __name__ == '__main__':
test_main()

4
Misc/NEWS
View File

@ -37,6 +37,10 @@ Core and Builtins
Library
-------
- Issue #4681: Allow mmap() to work on file sizes and offsets larger than
4GB, even on 32-bit builds. Initial patch by Ross Lagerwall, adapted for
32-bit Windows.
- Issue #11171: Fix detection of config/Makefile when --prefix !=
--exec-prefix, which caused Python to not start.

107
Modules/mmapmodule.c
View File

@ -90,7 +90,11 @@ typedef struct {
char * data;
size_t size;
size_t pos; /* relative to offset */
size_t offset;
#ifdef MS_WINDOWS
PY_LONG_LONG offset;
#else
off_t offset;
#endif
#ifdef MS_WINDOWS
HANDLE map_handle;
@ -424,7 +428,11 @@ mmap_size_method(mmap_object *self,
PyErr_SetFromErrno(mmap_module_error);
return NULL;
}
return PyInt_FromSsize_t(buf.st_size);
#ifdef HAVE_LARGEFILE_SUPPORT
return PyLong_FromLongLong(buf.st_size);
#else
return PyInt_FromLong(buf.st_size);
#endif
}
#endif /* UNIX */
}
@ -458,17 +466,10 @@ mmap_resize_method(mmap_object *self,
CloseHandle(self->map_handle);
self->map_handle = NULL;
/* Move to the desired EOF position */
#if SIZEOF_SIZE_T > 4
newSizeHigh = (DWORD)((self->offset + new_size) >> 32);
newSizeLow = (DWORD)((self->offset + new_size) & 0xFFFFFFFF);
off_hi = (DWORD)(self->offset >> 32);
off_lo = (DWORD)(self->offset & 0xFFFFFFFF);
#else
newSizeHigh = 0;
newSizeLow = (DWORD)(self->offset + new_size);
off_hi = 0;
off_lo = (DWORD)self->offset;
#endif
SetFilePointer(self->file_handle,
newSizeLow, &newSizeHigh, FILE_BEGIN);
/* Change the size of the file */
@ -1099,6 +1100,12 @@ _GetMapSize(PyObject *o, const char* param)
}
#ifdef UNIX
#ifdef HAVE_LARGEFILE_SUPPORT
#define _Py_PARSE_OFF_T "L"
#else
#define _Py_PARSE_OFF_T "l"
#endif
static PyObject *
new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
{
@ -1106,8 +1113,9 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
struct stat st;
#endif
mmap_object *m_obj;
PyObject *map_size_obj = NULL, *offset_obj = NULL;
Py_ssize_t map_size, offset;
PyObject *map_size_obj = NULL;
Py_ssize_t map_size;
off_t offset = 0;
int fd, flags = MAP_SHARED, prot = PROT_WRITE | PROT_READ;
int devzero = -1;
int access = (int)ACCESS_DEFAULT;
@ -1115,16 +1123,18 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
"flags", "prot",
"access", "offset", NULL};
if (!PyArg_ParseTupleAndKeywords(args, kwdict, "iO|iiiO", keywords,
if (!PyArg_ParseTupleAndKeywords(args, kwdict, "iO|iii" _Py_PARSE_OFF_T, keywords,
&fd, &map_size_obj, &flags, &prot,
&access, &offset_obj))
&access, &offset))
return NULL;
map_size = _GetMapSize(map_size_obj, "size");
if (map_size < 0)
return NULL;
offset = _GetMapSize(offset_obj, "offset");
if (offset < 0)
if (offset < 0) {
PyErr_SetString(PyExc_OverflowError,
"memory mapped offset must be positive");
return NULL;
}
if ((access != (int)ACCESS_DEFAULT) &&
((flags != MAP_SHARED) || (prot != (PROT_WRITE | PROT_READ))))
@ -1169,8 +1179,14 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
"mmap offset is greater than file size");
return NULL;
}
map_size = st.st_size - offset;
} else if ((size_t)offset + (size_t)map_size > st.st_size) {
off_t calc_size = st.st_size - offset;
map_size = calc_size;
if (map_size != calc_size) {
PyErr_SetString(PyExc_ValueError,
"mmap length is too large");
return NULL;
}
} else if (offset + (size_t)map_size > st.st_size) {
PyErr_SetString(PyExc_ValueError,
"mmap length is greater than file size");
return NULL;
@ -1230,12 +1246,19 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
#endif /* UNIX */
#ifdef MS_WINDOWS
/* A note on sizes and offsets: while the actual map size must hold in a
Py_ssize_t, both the total file size and the start offset can be longer
than a Py_ssize_t, so we use PY_LONG_LONG which is always 64-bit.
*/
static PyObject *
new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
{
mmap_object *m_obj;
PyObject *map_size_obj = NULL, *offset_obj = NULL;
Py_ssize_t map_size, offset;
PyObject *map_size_obj = NULL;
Py_ssize_t map_size;
PY_LONG_LONG offset = 0, size;
DWORD off_hi; /* upper 32 bits of offset */
DWORD off_lo; /* lower 32 bits of offset */
DWORD size_hi; /* upper 32 bits of size */
@ -1250,9 +1273,9 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
"tagname",
"access", "offset", NULL };
if (!PyArg_ParseTupleAndKeywords(args, kwdict, "iO|ziO", keywords,
if (!PyArg_ParseTupleAndKeywords(args, kwdict, "iO|ziL", keywords,
&fileno, &map_size_obj,
&tagname, &access, &offset_obj)) {
&tagname, &access, &offset)) {
return NULL;
}
@ -1277,9 +1300,11 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
map_size = _GetMapSize(map_size_obj, "size");
if (map_size < 0)
return NULL;
offset = _GetMapSize(offset_obj, "offset");
if (offset < 0)
if (offset < 0) {
PyErr_SetString(PyExc_OverflowError,
"memory mapped offset must be positive");
return NULL;
}
/* assume -1 and 0 both mean invalid filedescriptor
to 'anonymously' map memory.
@ -1342,28 +1367,26 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
return PyErr_SetFromWindowsErr(dwErr);
}
#if SIZEOF_SIZE_T > 4
m_obj->size = (((size_t)high)<<32) + low;
#else
if (high)
/* File is too large to map completely */
m_obj->size = (size_t)-1;
else
m_obj->size = low;
#endif
if (offset >= m_obj->size) {
size = (((PY_LONG_LONG) high) << 32) + low;
if (offset >= size) {
PyErr_SetString(PyExc_ValueError,
"mmap offset is greater than file size");
Py_DECREF(m_obj);
return NULL;
}
m_obj->size -= offset;
if (offset - size > PY_SSIZE_T_MAX)
/* Map area too large to fit in memory */
m_obj->size = (Py_ssize_t) -1;
else
m_obj->size = (Py_ssize_t) (size - offset);
} else {
m_obj->size = map_size;
size = offset + map_size;
}
}
else {
m_obj->size = map_size;
size = offset + map_size;
}
/* set the initial position */
@ -1383,22 +1406,10 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
m_obj->tagname = NULL;
m_obj->access = (access_mode)access;
/* DWORD is a 4-byte int. If we're on a box where size_t consumes
* more than 4 bytes, we need to break it apart. Else (size_t
* consumes 4 bytes), C doesn't define what happens if we shift
* right by 32, so we need different code.
*/
#if SIZEOF_SIZE_T > 4
size_hi = (DWORD)((offset + m_obj->size) >> 32);
size_lo = (DWORD)((offset + m_obj->size) & 0xFFFFFFFF);
size_hi = (DWORD)(size >> 32);
size_lo = (DWORD)(size & 0xFFFFFFFF);
off_hi = (DWORD)(offset >> 32);
off_lo = (DWORD)(offset & 0xFFFFFFFF);
#else
size_hi = 0;
size_lo = (DWORD)(offset + m_obj->size);
off_hi = 0;
off_lo = (DWORD)offset;
#endif
/* For files, it would be sufficient to pass 0 as size.
For anonymous maps, we have to pass the size explicitly. */
m_obj->map_handle = CreateFileMapping(m_obj->file_handle,