Issue #23152: Implement _Py_fstat() to support files larger than 2 GB on Windows.
fstat() may fail with EOVERFLOW on files larger than 2 GB because the file size type is an signed 32-bit integer.
diff --git a/Python/fileutils.c b/Python/fileutils.c
index c5c8d4e..8f3fdca 100644
--- a/Python/fileutils.c
+++ b/Python/fileutils.c
@@ -544,8 +544,145 @@
}
#endif
-#ifdef HAVE_STAT
+#if defined(HAVE_FSTAT) || defined(MS_WINDOWS)
+
+#ifdef MS_WINDOWS
+static __int64 secs_between_epochs = 11644473600; /* Seconds between 1.1.1601 and 1.1.1970 */
+
+static void
+FILE_TIME_to_time_t_nsec(FILETIME *in_ptr, time_t *time_out, int* nsec_out)
+{
+ /* XXX endianness. Shouldn't matter, as all Windows implementations are little-endian */
+ /* Cannot simply cast and dereference in_ptr,
+ since it might not be aligned properly */
+ __int64 in;
+ memcpy(&in, in_ptr, sizeof(in));
+ *nsec_out = (int)(in % 10000000) * 100; /* FILETIME is in units of 100 nsec. */
+ *time_out = Py_SAFE_DOWNCAST((in / 10000000) - secs_between_epochs, __int64, time_t);
+}
+
+void
+time_t_to_FILE_TIME(time_t time_in, int nsec_in, FILETIME *out_ptr)
+{
+ /* XXX endianness */
+ __int64 out;
+ out = time_in + secs_between_epochs;
+ out = out * 10000000 + nsec_in / 100;
+ memcpy(out_ptr, &out, sizeof(out));
+}
+
+/* Below, we *know* that ugo+r is 0444 */
+#if _S_IREAD != 0400
+#error Unsupported C library
+#endif
+static int
+attributes_to_mode(DWORD attr)
+{
+ int m = 0;
+ if (attr & FILE_ATTRIBUTE_DIRECTORY)
+ m |= _S_IFDIR | 0111; /* IFEXEC for user,group,other */
+ else
+ m |= _S_IFREG;
+ if (attr & FILE_ATTRIBUTE_READONLY)
+ m |= 0444;
+ else
+ m |= 0666;
+ return m;
+}
+
+int
+attribute_data_to_stat(BY_HANDLE_FILE_INFORMATION *info, ULONG reparse_tag, struct _Py_stat_struct *result)
+{
+ memset(result, 0, sizeof(*result));
+ result->st_mode = attributes_to_mode(info->dwFileAttributes);
+ result->st_size = (((__int64)info->nFileSizeHigh)<<32) + info->nFileSizeLow;
+ result->st_dev = info->dwVolumeSerialNumber;
+ result->st_rdev = result->st_dev;
+ FILE_TIME_to_time_t_nsec(&info->ftCreationTime, &result->st_ctime, &result->st_ctime_nsec);
+ FILE_TIME_to_time_t_nsec(&info->ftLastWriteTime, &result->st_mtime, &result->st_mtime_nsec);
+ FILE_TIME_to_time_t_nsec(&info->ftLastAccessTime, &result->st_atime, &result->st_atime_nsec);
+ result->st_nlink = info->nNumberOfLinks;
+ result->st_ino = (((__int64)info->nFileIndexHigh)<<32) + info->nFileIndexLow;
+ if (reparse_tag == IO_REPARSE_TAG_SYMLINK) {
+ /* first clear the S_IFMT bits */
+ result->st_mode ^= (result->st_mode & S_IFMT);
+ /* now set the bits that make this a symlink */
+ result->st_mode |= S_IFLNK;
+ }
+ result->st_file_attributes = info->dwFileAttributes;
+
+ return 0;
+}
+#endif
+
+/* Return information about a file.
+
+ On POSIX, use fstat().
+
+ On Windows, use GetFileType() and GetFileInformationByHandle() which support
+ files larger than 2 GB. fstat() may fail with EOVERFLOW on files larger
+ than 2 GB because the file size type is an signed 32-bit integer: see issue
+ #23152.
+ */
+int
+_Py_fstat(int fd, struct _Py_stat_struct *result)
+{
+#ifdef MS_WINDOWS
+ BY_HANDLE_FILE_INFORMATION info;
+ HANDLE h;
+ int type;
+
+ if (!_PyVerify_fd(fd))
+ h = INVALID_HANDLE_VALUE;
+ else
+ h = (HANDLE)_get_osfhandle(fd);
+
+ /* Protocol violation: we explicitly clear errno, instead of
+ setting it to a POSIX error. Callers should use GetLastError. */
+ errno = 0;
+
+ if (h == INVALID_HANDLE_VALUE) {
+ /* This is really a C library error (invalid file handle).
+ We set the Win32 error to the closes one matching. */
+ SetLastError(ERROR_INVALID_HANDLE);
+ return -1;
+ }
+ memset(result, 0, sizeof(*result));
+
+ type = GetFileType(h);
+ if (type == FILE_TYPE_UNKNOWN) {
+ DWORD error = GetLastError();
+ if (error != 0) {
+ return -1;
+ }
+ /* else: valid but unknown file */
+ }
+
+ if (type != FILE_TYPE_DISK) {
+ if (type == FILE_TYPE_CHAR)
+ result->st_mode = _S_IFCHR;
+ else if (type == FILE_TYPE_PIPE)
+ result->st_mode = _S_IFIFO;
+ return 0;
+ }
+
+ if (!GetFileInformationByHandle(h, &info)) {
+ return -1;
+ }
+
+ attribute_data_to_stat(&info, 0, result);
+ /* specific to fstat() */
+ result->st_ino = (((__int64)info.nFileIndexHigh)<<32) + info.nFileIndexLow;
+ return 0;
+#else
+ return fstat(fd, result);
+#endif
+}
+#endif /* HAVE_FSTAT || MS_WINDOWS */
+
+
+#ifdef HAVE_STAT
/* Call _wstat() on Windows, or encode the path to the filesystem encoding and
call stat() otherwise. Only fill st_mode attribute on Windows.
@@ -578,7 +715,8 @@
#endif
}
-#endif
+#endif /* HAVE_STAT */
+
static int
get_inheritable(int fd, int raise)