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+/* macros useful in interpreting size-related values in struct stat.
+ Copyright (C) 1989, 1991-2016 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* *INDENT-OFF* */
+/*
+ Macros defined by this file (s is an rvalue of type struct stat):
+
+ DEV_BSIZE: The device blocksize. But use ST_NBLOCKSIZE instead.
+ ST_BLKSIZE(s): Preferred (in the sense of best performance) I/O blocksize
+ for the file, in bytes.
+ ST_NBLOCKS(s): Number of blocks in the file, including indirect blocks.
+ ST_NBLOCKSIZE: Size of blocks used when calculating ST_NBLOCKS.
+ */
+/* *INDENT-ON* */
+
+#ifndef STAT_SIZE_H
+#define STAT_SIZE_H
+
+/* sys/param.h may define DEV_BSIZE */
+#if HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+
+
+/* Get or fake the disk device blocksize.
+ Usually defined by sys/param.h (if at all). */
+#if !defined DEV_BSIZE && defined BSIZE
+#define DEV_BSIZE BSIZE
+#endif
+#if !defined DEV_BSIZE && defined BBSIZE /* SGI sys/param.h */
+#define DEV_BSIZE BBSIZE
+#endif
+#ifndef DEV_BSIZE
+#define DEV_BSIZE 4096
+#endif
+
+
+
+/* Extract or fake data from a 'struct stat'.
+ ST_BLKSIZE: Preferred I/O blocksize for the file, in bytes.
+ ST_NBLOCKS: Number of blocks in the file, including indirect blocks.
+ ST_NBLOCKSIZE: Size of blocks used when calculating ST_NBLOCKS. */
+#ifndef HAVE_STRUCT_STAT_ST_BLOCKS
+#define ST_BLKSIZE(statbuf) DEV_BSIZE
+ /* coreutils' fileblocks.c also uses BSIZE. */
+#if defined _POSIX_SOURCE || !defined BSIZE
+#define ST_NBLOCKS(statbuf) \
+ ((statbuf).st_size / ST_NBLOCKSIZE + ((statbuf).st_size % ST_NBLOCKSIZE != 0))
+#else
+ /* This definition calls st_blocks, which is in the fileblocks module. */
+#define ST_NBLOCKS(statbuf) \
+ (S_ISREG ((statbuf).st_mode) || S_ISDIR ((statbuf).st_mode) ? \
+ st_blocks ((statbuf).st_size) : 0)
+#endif
+#else
+/* When running 'rsh hpux11-system cat any-file', cat would
+ determine that the output stream had an st_blksize of 2147421096.
+ Conversely st_blksize can be 2 GiB (or maybe even larger) with XFS
+ on 64-bit hosts. Somewhat arbitrarily, limit the "optimal" block
+ size to SIZE_MAX / 8 + 1. (Dividing SIZE_MAX by only 4 wouldn't
+ suffice, since "cat" sometimes multiplies the result by 4.) If
+ anyone knows of a system for which this limit is too small, please
+ report it as a bug in this code. */
+#define ST_BLKSIZE(statbuf) ((0 < (statbuf).st_blksize \
+ && (size_t) ((statbuf).st_blksize) <= ((size_t)-1) / 8 + 1) \
+ ? (size_t) ((statbuf).st_blksize) : DEV_BSIZE)
+#if defined hpux || defined __hpux__ || defined __hpux
+ /* HP-UX counts st_blocks in 1024-byte units.
+ This loses when mixing HP-UX and BSD file systems with NFS. */
+#define ST_NBLOCKSIZE 1024
+#endif
+#endif
+
+#ifndef ST_NBLOCKS
+#define ST_NBLOCKS(statbuf) ((statbuf).st_blocks)
+#endif
+
+#ifndef ST_NBLOCKSIZE
+#ifdef S_BLKSIZE
+#define ST_NBLOCKSIZE S_BLKSIZE
+#else
+#define ST_NBLOCKSIZE 512
+#endif
+#endif
+
+#endif /* STAT_SIZE_H */