diff options
Diffstat (limited to 'lib/libutil')
| -rw-r--r-- | lib/libutil/humanize_number.3 | 17 | ||||
| -rw-r--r-- | lib/libutil/humanize_number.c | 74 |
2 files changed, 54 insertions, 37 deletions
diff --git a/lib/libutil/humanize_number.3 b/lib/libutil/humanize_number.3 index 32df6f8..3a883ca 100644 --- a/lib/libutil/humanize_number.3 +++ b/lib/libutil/humanize_number.3 @@ -28,7 +28,7 @@ .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" -.Dd Apr 12, 2011 +.Dd October 7, 2013 .Dt HUMANIZE_NUMBER 3 .Os .Sh NAME @@ -140,7 +140,7 @@ The following flags may be passed in .Fa flags : .Bl -tag -width ".Dv HN_DIVISOR_1000" -offset indent .It Dv HN_DECIMAL -If the final result is less than 10, display it using one digit. +If the final result is less than 10, display it using one decimal place. .It Dv HN_NOSPACE Do not put a space between .Fa number @@ -160,13 +160,18 @@ This flag has no effect when is also specified. .El .Sh RETURN VALUES -The -.Fn humanize_number -function returns the number of characters stored in +Upon success, the +.Nm +function returns the number of characters that would have been stored in .Fa buf (excluding the terminating .Dv NUL ) -upon success, or \-1 upon failure. +if +.Fa buf +was large enough, or \-1 upon failure. +Even upon failure, the contents of +.Fa buf +may be modified. If .Dv HN_GETSCALE is specified, the prefix index number will be returned instead. diff --git a/lib/libutil/humanize_number.c b/lib/libutil/humanize_number.c index 1cad1cf..b773422 100644 --- a/lib/libutil/humanize_number.c +++ b/lib/libutil/humanize_number.c @@ -2,6 +2,7 @@ /* * Copyright (c) 1997, 1998, 1999, 2002 The NetBSD Foundation, Inc. + * Copyright 2013 John-Mark Gurney <jmg@FreeBSD.org> * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation @@ -50,15 +51,26 @@ humanize_number(char *buf, size_t len, int64_t quotient, { const char *prefixes, *sep; int i, r, remainder, s1, s2, sign; + int divisordeccut; int64_t divisor, max; size_t baselen; - assert(buf != NULL); - assert(suffix != NULL); - assert(scale >= 0); - assert(scale < maxscale || (((scale & (HN_AUTOSCALE | HN_GETSCALE)) != 0))); - assert(!((flags & HN_DIVISOR_1000) && (flags & HN_IEC_PREFIXES))); + /* Since so many callers don't check -1, NUL terminate the buffer */ + if (len > 0) + buf[0] = '\0'; + /* validate args */ + if (buf == NULL || suffix == NULL) + return (-1); + if (scale < 0) + return (-1); + else if (scale >= maxscale && + ((scale & ~(HN_AUTOSCALE|HN_GETSCALE)) != 0)) + return (-1); + if ((flags & HN_DIVISOR_1000) && (flags & HN_IEC_PREFIXES)) + return (-1); + + /* setup parameters */ remainder = 0; if (flags & HN_IEC_PREFIXES) { @@ -73,34 +85,32 @@ humanize_number(char *buf, size_t len, int64_t quotient, * an assertion earlier). */ divisor = 1024; + divisordeccut = 973; /* ceil(.95 * 1024) */ if (flags & HN_B) prefixes = "B\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; else prefixes = "\0\0\0Ki\0Mi\0Gi\0Ti\0Pi\0Ei"; } else { baselen = 1; - if (flags & HN_DIVISOR_1000) + if (flags & HN_DIVISOR_1000) { divisor = 1000; - else + divisordeccut = 950; + if (flags & HN_B) + prefixes = "B\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; + else + prefixes = "\0\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; + } else { divisor = 1024; - - if (flags & HN_B) - prefixes = "B\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; - else - prefixes = "\0\0\0k\0\0M\0\0G\0\0T\0\0P\0\0E"; + divisordeccut = 973; /* ceil(.95 * 1024) */ + if (flags & HN_B) + prefixes = "B\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; + else + prefixes = "\0\0\0K\0\0M\0\0G\0\0T\0\0P\0\0E"; + } } #define SCALE2PREFIX(scale) (&prefixes[(scale) * 3]) - if (scale < 0 || (scale >= maxscale && - (scale & (HN_AUTOSCALE | HN_GETSCALE)) == 0)) - return (-1); - - if (buf == NULL || suffix == NULL) - return (-1); - - if (len > 0) - buf[0] = '\0'; if (quotient < 0) { sign = -1; quotient = -quotient; @@ -132,8 +142,8 @@ humanize_number(char *buf, size_t len, int64_t quotient, * divide once more. */ for (i = 0; - (quotient >= max || (quotient == max - 1 && remainder >= 950)) && - i < maxscale; i++) { + (quotient >= max || (quotient == max - 1 && + remainder >= divisordeccut)) && i < maxscale; i++) { remainder = quotient % divisor; quotient /= divisor; } @@ -148,20 +158,22 @@ humanize_number(char *buf, size_t len, int64_t quotient, } /* If a value <= 9.9 after rounding and ... */ - if (quotient <= 9 && remainder < 950 && i > 0 && flags & HN_DECIMAL) { - /* baselen + \0 + .N */ - if (len < baselen + 1 + 2) - return (-1); - s1 = (int)quotient + ((remainder + 50) / 1000); - s2 = ((remainder + 50) / 100) % 10; + /* + * XXX - should we make sure there is enough space for the decimal + * place and if not, don't do HN_DECIMAL? + */ + if (((quotient == 9 && remainder < divisordeccut) || quotient < 9) && + i > 0 && flags & HN_DECIMAL) { + s1 = (int)quotient + ((remainder * 10 + divisor / 2) / + divisor / 10); + s2 = ((remainder * 10 + divisor / 2) / divisor) % 10; r = snprintf(buf, len, "%d%s%d%s%s%s", sign * s1, localeconv()->decimal_point, s2, sep, SCALE2PREFIX(i), suffix); } else r = snprintf(buf, len, "%" PRId64 "%s%s%s", - sign * (quotient + (remainder + 50) / 1000), + sign * (quotient + (remainder + divisor / 2) / divisor), sep, SCALE2PREFIX(i), suffix); return (r); } - |
