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-rw-r--r--grub-core/lib/division.c74
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;
+}