bug [ 728515 ] mmap's resize method resizes the file in win32 but not unix
diff --git a/Doc/lib/libmmap.tex b/Doc/lib/libmmap.tex
index 0d7baa1..c7ab348 100644
--- a/Doc/lib/libmmap.tex
+++ b/Doc/lib/libmmap.tex
@@ -132,6 +132,7 @@
\end{methoddesc}
\begin{methoddesc}{resize}{\var{newsize}}
+ Resizes the map and the underlying file, if any.
If the mmap was created with \constant{ACCESS_READ} or
\constant{ACCESS_COPY}, resizing the map will throw a \exception{TypeError} exception.
\end{methoddesc}
diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index efb7180..a0386ef 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -120,6 +120,14 @@
else:
verify(0, 'Could seek beyond the new size')
+ # Check that the underlying file is truncated too
+ # (bug #728515)
+ f = open(TESTFN)
+ f.seek(0, 2)
+ verify(f.tell() == 512, 'Underlying file not truncated')
+ f.close()
+ verify(m.size() == 512, 'New size not reflected in file')
+
m.close()
finally:
diff --git a/Misc/NEWS b/Misc/NEWS
index 0171492..5bd2dc2 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -128,6 +128,9 @@
Extension Modules
-----------------
+- Bug #728515: mmap.resize() now resizes the file on Unix as it did
+ on Windows.
+
- Patch #1180695: Add nanosecond stat resolution, and st_gen,
st_birthtime for FreeBSD.
diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index aaa4925..f58e0f1 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -421,6 +421,11 @@
return NULL;
#else
} else {
+ if (ftruncate(self->fd, new_size) == -1) {
+ PyErr_SetFromErrno(mmap_module_error);
+ return NULL;
+ }
+
void *newmap;
#ifdef MREMAP_MAYMOVE
@@ -910,7 +915,12 @@
if (m_obj == NULL) {return NULL;}
m_obj->size = (size_t) map_size;
m_obj->pos = (size_t) 0;
- m_obj->fd = fd;
+ m_obj->fd = dup(fd);
+ if (m_obj->fd == -1) {
+ Py_DECREF(m_obj);
+ PyErr_SetFromErrno(mmap_module_error);
+ return NULL;
+ }
m_obj->data = mmap(NULL, map_size,
prot, flags,
fd, 0);