diff options
Diffstat (limited to 'grub-core/lib/division.c')
-rw-r--r-- | grub-core/lib/division.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/grub-core/lib/division.c b/grub-core/lib/division.c new file mode 100644 index 0000000..35606fe --- /dev/null +++ b/grub-core/lib/division.c @@ -0,0 +1,74 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2015 Free Software Foundation, Inc. + * + * GRUB 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. + * + * GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/misc.h> +#include <grub/dl.h> + +GRUB_MOD_LICENSE ("GPLv3+"); + +static grub_uint64_t +abs64(grub_int64_t a) +{ + return a > 0 ? a : -a; +} + +grub_int64_t +grub_divmod64s (grub_int64_t n, + grub_int64_t d, + grub_int64_t *ro) +{ + grub_uint64_t ru; + grub_int64_t q, r; + q = grub_divmod64 (abs64(n), abs64(d), &ru); + r = ru; + /* Now: |n| = |d| * q + r */ + if (n < 0) + { + /* -|n| = |d| * (-q) + (-r) */ + q = -q; + r = -r; + } + /* Now: n = |d| * q + r */ + if (d < 0) + { + /* n = (-|d|) * (-q) + r */ + q = -q; + } + /* Now: n = d * q + r */ + if (ro) + *ro = r; + return q; +} + +grub_uint32_t +grub_divmod32 (grub_uint32_t n, grub_uint32_t d, grub_uint32_t *ro) +{ + grub_uint64_t q, r; + q = grub_divmod64 (n, d, &r); + *ro = r; + return q; +} + +grub_int32_t +grub_divmod32s (grub_int32_t n, grub_int32_t d, grub_int32_t *ro) +{ + grub_int64_t q, r; + q = grub_divmod64s (n, d, &r); + *ro = r; + return q; +} |