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Diffstat (limited to 'lib/libzutil/zutil_nicenum.c')
| -rw-r--r-- | lib/libzutil/zutil_nicenum.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/lib/libzutil/zutil_nicenum.c b/lib/libzutil/zutil_nicenum.c new file mode 100644 index 000000000..9a81011fc --- /dev/null +++ b/lib/libzutil/zutil_nicenum.c @@ -0,0 +1,157 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ + +/* + * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. + */ + +#include <math.h> +#include <stdio.h> +#include <libzutil.h> + +/* + * Convert a number to an appropriately human-readable output. + */ +void +zfs_nicenum_format(uint64_t num, char *buf, size_t buflen, + enum zfs_nicenum_format format) +{ + uint64_t n = num; + int index = 0; + const char *u; + const char *units[3][7] = { + [ZFS_NICENUM_1024] = {"", "K", "M", "G", "T", "P", "E"}, + [ZFS_NICENUM_BYTES] = {"B", "K", "M", "G", "T", "P", "E"}, + [ZFS_NICENUM_TIME] = {"ns", "us", "ms", "s", "?", "?", "?"} + }; + + const int units_len[] = {[ZFS_NICENUM_1024] = 6, + [ZFS_NICENUM_BYTES] = 6, + [ZFS_NICENUM_TIME] = 4}; + + const int k_unit[] = { [ZFS_NICENUM_1024] = 1024, + [ZFS_NICENUM_BYTES] = 1024, + [ZFS_NICENUM_TIME] = 1000}; + + double val; + + if (format == ZFS_NICENUM_RAW) { + snprintf(buf, buflen, "%llu", (u_longlong_t)num); + return; + } else if (format == ZFS_NICENUM_RAWTIME && num > 0) { + snprintf(buf, buflen, "%llu", (u_longlong_t)num); + return; + } else if (format == ZFS_NICENUM_RAWTIME && num == 0) { + snprintf(buf, buflen, "%s", "-"); + return; + } + + while (n >= k_unit[format] && index < units_len[format]) { + n /= k_unit[format]; + index++; + } + + u = units[format][index]; + + /* Don't print zero latencies since they're invalid */ + if ((format == ZFS_NICENUM_TIME) && (num == 0)) { + (void) snprintf(buf, buflen, "-"); + } else if ((index == 0) || ((num % + (uint64_t)powl(k_unit[format], index)) == 0)) { + /* + * If this is an even multiple of the base, always display + * without any decimal precision. + */ + (void) snprintf(buf, buflen, "%llu%s", (u_longlong_t)n, u); + + } else { + /* + * We want to choose a precision that reflects the best choice + * for fitting in 5 characters. This can get rather tricky when + * we have numbers that are very close to an order of magnitude. + * For example, when displaying 10239 (which is really 9.999K), + * we want only a single place of precision for 10.0K. We could + * develop some complex heuristics for this, but it's much + * easier just to try each combination in turn. + */ + int i; + for (i = 2; i >= 0; i--) { + val = (double)num / + (uint64_t)powl(k_unit[format], index); + + /* + * Don't print floating point values for time. Note, + * we use floor() instead of round() here, since + * round can result in undesirable results. For + * example, if "num" is in the range of + * 999500-999999, it will print out "1000us". This + * doesn't happen if we use floor(). + */ + if (format == ZFS_NICENUM_TIME) { + if (snprintf(buf, buflen, "%d%s", + (unsigned int) floor(val), u) <= 5) + break; + + } else { + if (snprintf(buf, buflen, "%.*f%s", i, + val, u) <= 5) + break; + } + } + } +} + +/* + * Convert a number to an appropriately human-readable output. + */ +void +zfs_nicenum(uint64_t num, char *buf, size_t buflen) +{ + zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_1024); +} + +/* + * Convert a time to an appropriately human-readable output. + * @num: Time in nanoseconds + */ +void +zfs_nicetime(uint64_t num, char *buf, size_t buflen) +{ + zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_TIME); +} + +/* + * Print out a raw number with correct column spacing + */ +void +zfs_niceraw(uint64_t num, char *buf, size_t buflen) +{ + zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_RAW); +} + +/* + * Convert a number of bytes to an appropriately human-readable output. + */ +void +zfs_nicebytes(uint64_t num, char *buf, size_t buflen) +{ + zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_BYTES); +} |