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-rw-r--r--contrib/syslinux-4.02/core/fs/btrfs/crc32c.h50
1 files changed, 50 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/core/fs/btrfs/crc32c.h b/contrib/syslinux-4.02/core/fs/btrfs/crc32c.h
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index 0000000..2c31738
--- /dev/null
+++ b/contrib/syslinux-4.02/core/fs/btrfs/crc32c.h
@@ -0,0 +1,50 @@
+/*
+ * Copied from Linux kernel crypto/crc32c.c
+ * Copyright (c) 2004 Cisco Systems, Inc.
+ * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * This program 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 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+/*
+ * This is the CRC-32C table
+ * Generated with:
+ * width = 32 bits
+ * poly = 0x1EDC6F41
+ * reflect input bytes = true
+ * reflect output bytes = true
+ */
+
+static u32 crc32c_table[256];
+
+/*
+ * Steps through buffer one byte at at time, calculates reflected
+ * crc using table.
+ */
+
+static inline u32 crc32c_le(u32 crc, const char *data, size_t length)
+{
+ while (length--)
+ crc = crc32c_table[(u8)(crc ^ *data++)] ^ (crc >> 8);
+
+ return crc;
+}
+
+static inline void btrfs_init_crc32c(void)
+{
+ int i, j;
+ u32 v;
+ const u32 poly = 0x82F63B78; /* Bit-reflected CRC32C polynomial */
+
+ for (i = 0; i < 256; i++) {
+ v = i;
+ for (j = 0; j < 8; j++) {
+ v = (v >> 1) ^ ((v & 1) ? poly : 0);
+ }
+ crc32c_table[i] = v;
+ }
+}