diff options
| -rw-r--r-- | src/df.c | 64 |
1 files changed, 30 insertions, 34 deletions
@@ -227,31 +227,6 @@ df_readable (int negative, uintmax_t n, char *buf, } } -/* Return the ceiling of N * 100 / D. Avoid the ceil function, so that - we needn't link the math library. */ -static double -ceil_percent (uintmax_t n, uintmax_t d) -{ - if (n <= (uintmax_t) -1 / 100) - { - uintmax_t n100 = n * 100; - return n100 / d + (n100 % d != 0); - } - else - { - /* Avoid integer overflow. We should use multiple precision - arithmetic here, but we'll be lazy and resort to floating - point. This can yield answers that are slightly off. In - practice it is quite rare to overflow uintmax_t, so this is - good enough for now. */ - double pct = n * 100.0 / d; - double ipct = (int) pct; - if (ipct - 1 < pct && pct <= ipct + 1) - pct = ipct + (ipct < pct); - return pct; - } -} - /* Display a space listing for the disk device with absolute path DISK. If MOUNT_POINT is non-NULL, it is the path of the root of the filesystem on DISK. @@ -277,7 +252,7 @@ show_dev (const char *disk, const char *mount_point, const char *fstype, uintmax_t available_to_root; uintmax_t used; int negate_used; - uintmax_t nonroot_total; + double pct = -1; if (me_remote && show_local_fs) return; @@ -373,15 +348,36 @@ show_dev (const char *disk, const char *mount_point, const char *fstype, width, df_readable (negate_available, available, buf[2], input_units, output_units)); - if (used == -1 || available == -1 - || ! (nonroot_total = ((negate_used ? - used : used) - + (negate_available ? - available : available)))) - printf ("%*s", use_width, "- "); + if (used != -1 && available != -1) + { + /* The following floating-point calculations can suffer from + minor rounding errors, but making them precise requires + multiple precision arithmetic, and it's not worth the + aggravation. */ + + double u = used; + double a = available; + double nonroot_total = ((negate_used ? - u : u) + + (negate_available ? - a : a)); + if (nonroot_total) + { + pct = u * 100 / nonroot_total; + + if (posix_format) + { + /* Like `pct = ceil (pct);', but avoid ceil so that + the math library needn't be linked. */ + double ipct = (long) pct; + if (ipct - 1 < pct && pct <= ipct + 1) + pct = ipct + (ipct < pct); + } + } + } + + if (0 <= pct) + printf ("%*.0f%%", use_width - 1, pct); else - printf ("%*.0f%%", use_width - 1, - (posix_format - ? ceil_percent (used, nonroot_total) - : used * 100.0 / nonroot_total)); + printf ("%*s", use_width, "- "); if (mount_point) { |