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-rw-r--r--lib/ext2fs/getsectsize.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/lib/ext2fs/getsectsize.c b/lib/ext2fs/getsectsize.c
new file mode 100644
index 0000000..bd978c5
--- /dev/null
+++ b/lib/ext2fs/getsectsize.c
@@ -0,0 +1,151 @@
+/*
+ * getsectsize.c --- get the sector size of a device.
+ *
+ * Copyright (C) 1995, 1995 Theodore Ts'o.
+ * Copyright (C) 2003 VMware, Inc.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#ifndef _LARGEFILE_SOURCE
+#define _LARGEFILE_SOURCE
+#endif
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+
+#include "config.h"
+#include <stdio.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <fcntl.h>
+#ifdef HAVE_SYS_DISK_H
+#include <sys/disk.h>
+#endif
+#ifdef HAVE_LINUX_FD_H
+#include <sys/ioctl.h>
+#include <linux/fd.h>
+#endif
+
+#if defined(__linux__) && defined(_IO)
+#if !defined(BLKSSZGET)
+#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
+#endif
+#if !defined(BLKPBSZGET)
+#define BLKPBSZGET _IO(0x12,123)/* get block physical sector size */
+#endif
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+/*
+ * Returns the logical sector size of a device
+ */
+errcode_t ext2fs_get_device_sectsize(const char *file, int *sectsize)
+{
+#ifdef _WIN32
+ *sectsize = 512; // just guessing
+ return 0;
+#else // not _WIN32
+
+ int fd;
+
+ fd = ext2fs_open_file(file, O_RDONLY, 0);
+ if (fd < 0)
+ return errno;
+
+#ifdef BLKSSZGET
+ if (ioctl(fd, BLKSSZGET, sectsize) >= 0) {
+ close(fd);
+ return 0;
+ }
+#endif
+#ifdef DIOCGSECTORSIZE
+ if (ioctl(fd, DIOCGSECTORSIZE, sectsize) >= 0) {
+ close(fd);
+ return 0;
+ }
+#endif
+ *sectsize = 0;
+ close(fd);
+ return 0;
+
+#endif // ifdef _WIN32
+}
+
+/*
+ * Return desired alignment for direct I/O
+ */
+int ext2fs_get_dio_alignment(int fd)
+{
+ int align = 0;
+
+#ifdef BLKSSZGET
+ if (ioctl(fd, BLKSSZGET, &align) < 0)
+ align = 0;
+#endif
+#ifdef DIOCGSECTORSIZE
+ if (align <= 0 &&
+ ioctl(fd, DIOCGSECTORSIZE, &align) < 0)
+ align = 0;
+#endif
+
+#ifdef _SC_PAGESIZE
+ if (align <= 0)
+ align = sysconf(_SC_PAGESIZE);
+#endif
+#ifdef HAVE_GETPAGESIZE
+ if (align <= 0)
+ align = getpagesize();
+#endif
+ if (align <= 0)
+ align = 4096;
+
+ return align;
+}
+
+/*
+ * Returns the physical sector size of a device
+ */
+errcode_t ext2fs_get_device_phys_sectsize(const char *file, int *sectsize)
+{
+#ifdef _WIN32
+
+ return ext2fs_get_device_sectsize(file, sectsize);
+
+#else // not _WIN32
+
+ int fd;
+
+ fd = ext2fs_open_file(file, O_RDONLY, 0);
+ if (fd < 0)
+ return errno;
+
+#ifdef BLKPBSZGET
+ if (ioctl(fd, BLKPBSZGET, sectsize) >= 0) {
+ close(fd);
+ return 0;
+ }
+#endif
+#ifdef DIOCGSECTORSIZE
+ /* This isn't really the physical sector size, but FreeBSD
+ * doesn't seem to have this concept. */
+ if (ioctl(fd, DIOCGSECTORSIZE, sectsize) >= 0) {
+ close(fd);
+ return 0;
+ }
+#endif
+ *sectsize = 0;
+ close(fd);
+ return 0;
+
+#endif // ifdef _WIN32
+}