Bug ID: JDK-6631353 Simplify io_util_md.c handleLseek using SetFilePointerEx (win)

Type: Bug
Component: core-libs
Sub-Component: java.io
Affected Version: 7

Priority: P4
Status: Closed
Resolution: Not an Issue
OS: generic
CPU: generic

Submitted: 2007-11-17
Updated: 2012-01-08
Resolved: 2012-01-08

The implementation of io_util_md.c handleLseek
can be simplified and sped up a bit using the Microsoft-recommended
SetFilePointerEx instead of SetFilePointer

EVALUATION The code was changed to use SetFilePointerEx as part of the changes to 6402006.

08-01-2012

EVALUATION Probably worth doing, but only if changes are made throughout the JDK, replacing SetFilePointer and GetFileSize, etc. with their Ex counterparts.

18-11-2007

EVALUATION Indeed. @@ -535,28 +542,14 @@ jlong handleLseek(jlong fd, jlong offset, jint whence) { - DWORD lowPos = 0; - long highPos = 0; - DWORD op = FILE_CURRENT; - HANDLE h = (HANDLE)fd; - - if (whence == SEEK_END) { - op = FILE_END; - } - if (whence == SEEK_CUR) { - op = FILE_CURRENT; - } - if (whence == SEEK_SET) { - op = FILE_BEGIN; - } - - lowPos = (DWORD)offset; - highPos = (long)(offset >> 32); - lowPos = SetFilePointer(h, lowPos, &highPos, op); - if (lowPos == ((DWORD)-1)) { - if (GetLastError() != ERROR_SUCCESS) { + LARGE_INTEGER li; + const DWORD moveMethod = ((whence == SEEK_SET) ? FILE_BEGIN : + (whence == SEEK_CUR) ? FILE_CURRENT : + (whence == SEEK_END) ? FILE_END : + -1 ); + li.QuadPart = offset; + if (SetFilePointerEx((HANDLE) fd, li, &li, moveMethod) == 0) return -1; - } - } - return (((jlong)highPos) << 32) | lowPos; + + return li.QuadPart; }

17-11-2007

Relates :	JDK-6402006 - FileInputStream.available() returns negative values when reading a large file
Relates :	JDK-4960438 - (process) Need IO redirection API for subprocesses