Issue #7332: Remove the 16KB stack-based buffer in
PyMarshal_ReadLastObjectFromFile, which doesn't bring any noticeable
benefit compared to the dynamic memory allocation fallback. Patch by
Charles-François Natali.
diff --git a/Python/marshal.c b/Python/marshal.c
index 9e4a692..14f7134 100644
--- a/Python/marshal.c
+++ b/Python/marshal.c
@@ -1126,23 +1126,13 @@
PyObject *
PyMarshal_ReadLastObjectFromFile(FILE *fp)
{
-/* 75% of 2.1's .pyc files can exploit SMALL_FILE_LIMIT.
- * REASONABLE_FILE_LIMIT is by defn something big enough for Tkinter.pyc.
- */
-#define SMALL_FILE_LIMIT (1L << 14)
+/* REASONABLE_FILE_LIMIT is by defn something big enough for Tkinter.pyc. */
#define REASONABLE_FILE_LIMIT (1L << 18)
#ifdef HAVE_FSTAT
off_t filesize;
-#endif
-#ifdef HAVE_FSTAT
filesize = getfilesize(fp);
- if (filesize > 0) {
- char buf[SMALL_FILE_LIMIT];
- char* pBuf = NULL;
- if (filesize <= SMALL_FILE_LIMIT)
- pBuf = buf;
- else if (filesize <= REASONABLE_FILE_LIMIT)
- pBuf = (char *)PyMem_MALLOC(filesize);
+ if (filesize > 0 && filesize <= REASONABLE_FILE_LIMIT) {
+ char* pBuf = (char *)PyMem_MALLOC(filesize);
if (pBuf != NULL) {
PyObject* v;
size_t n;
@@ -1150,8 +1140,7 @@
is smaller than REASONABLE_FILE_LIMIT */
n = fread(pBuf, 1, (int)filesize, fp);
v = PyMarshal_ReadObjectFromString(pBuf, n);
- if (pBuf != buf)
- PyMem_FREE(pBuf);
+ PyMem_FREE(pBuf);
return v;
}
@@ -1162,7 +1151,6 @@
*/
return PyMarshal_ReadObjectFromFile(fp);
-#undef SMALL_FILE_LIMIT
#undef REASONABLE_FILE_LIMIT
}