Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 187 insertions, 0 deletions

diff --git a/lib/jhash.c b/lib/jhash.c
new file mode 100644
index 0000000..0d561ef
--- /dev/null
+++ b/lib/jhash.c
@@ -0,0 +1,187 @@
+/* jhash.h: Jenkins hash support.
+ *
+ * Copyright (C) 1996 Bob Jenkins (bob_jenkins@burtleburtle.net)
+ *
+ * http://burtleburtle.net/bob/hash/
+ *
+ * These are the credits from Bob's sources:
+ *
+ * lookup2.c, by Bob Jenkins, December 1996, Public Domain.
+ * hash(), hash2(), hash3, and mix() are externally useful functions.
+ * Routines to test the hash are included if SELF_TEST is defined.
+ * You can use this free for any purpose.  It has no warranty.
+ *
+ * Copyright (C) 2003 David S. Miller (davem@redhat.com)
+ *
+ * I've modified Bob's hash to be useful in the Linux kernel, and
+ * any bugs present are surely my fault.  -DaveM
+ */
+
+#include "zebra.h"
+#include "jhash.h"
+
+/* The golden ration: an arbitrary value */
+#define JHASH_GOLDEN_RATIO  0x9e3779b9
+
+/* NOTE: Arguments are modified. */
+#define __jhash_mix(a, b, c)                                                   \
+	{                                                                      \
+		a -= b;                                                        \
+		a -= c;                                                        \
+		a ^= (c >> 13);                                                \
+		b -= c;                                                        \
+		b -= a;                                                        \
+		b ^= (a << 8);                                                 \
+		c -= a;                                                        \
+		c -= b;                                                        \
+		c ^= (b >> 13);                                                \
+		a -= b;                                                        \
+		a -= c;                                                        \
+		a ^= (c >> 12);                                                \
+		b -= c;                                                        \
+		b -= a;                                                        \
+		b ^= (a << 16);                                                \
+		c -= a;                                                        \
+		c -= b;                                                        \
+		c ^= (b >> 5);                                                 \
+		a -= b;                                                        \
+		a -= c;                                                        \
+		a ^= (c >> 3);                                                 \
+		b -= c;                                                        \
+		b -= a;                                                        \
+		b ^= (a << 10);                                                \
+		c -= a;                                                        \
+		c -= b;                                                        \
+		c ^= (b >> 15);                                                \
+	}
+
+/* The most generic version, hashes an arbitrary sequence
+ * of bytes.  No alignment or length assumptions are made about
+ * the input key.
+ */
+uint32_t jhash(const void *key, uint32_t length, uint32_t initval)
+{
+	uint32_t a, b, c, len;
+	const uint8_t *k = key;
+
+	len = length;
+	a = b = JHASH_GOLDEN_RATIO;
+	c = initval;
+
+	while (len >= 12) {
+		a += (k[0] + ((uint32_t)k[1] << 8) + ((uint32_t)k[2] << 16)
+		      + ((uint32_t)k[3] << 24));
+		b += (k[4] + ((uint32_t)k[5] << 8) + ((uint32_t)k[6] << 16)
+		      + ((uint32_t)k[7] << 24));
+		c += (k[8] + ((uint32_t)k[9] << 8) + ((uint32_t)k[10] << 16)
+		      + ((uint32_t)k[11] << 24));
+
+		__jhash_mix(a, b, c);
+
+		k += 12;
+		len -= 12;
+	}
+
+	c += length;
+	switch (len) {
+	case 11:
+		c += ((uint32_t)k[10] << 24);
+	/* fallthru */
+	case 10:
+		c += ((uint32_t)k[9] << 16);
+	/* fallthru */
+	case 9:
+		c += ((uint32_t)k[8] << 8);
+	/* fallthru */
+	case 8:
+		b += ((uint32_t)k[7] << 24);
+	/* fallthru */
+	case 7:
+		b += ((uint32_t)k[6] << 16);
+	/* fallthru */
+	case 6:
+		b += ((uint32_t)k[5] << 8);
+	/* fallthru */
+	case 5:
+		b += k[4];
+	/* fallthru */
+	case 4:
+		a += ((uint32_t)k[3] << 24);
+	/* fallthru */
+	case 3:
+		a += ((uint32_t)k[2] << 16);
+	/* fallthru */
+	case 2:
+		a += ((uint32_t)k[1] << 8);
+	/* fallthru */
+	case 1:
+		a += k[0];
+	}
+
+	__jhash_mix(a, b, c);
+
+	return c;
+}
+
+/* A special optimized version that handles 1 or more of uint32_ts.
+ * The length parameter here is the number of uint32_ts in the key.
+ */
+uint32_t jhash2(const uint32_t *k, uint32_t length, uint32_t initval)
+{
+	uint32_t a, b, c, len;
+
+	a = b = JHASH_GOLDEN_RATIO;
+	c = initval;
+	len = length;
+
+	while (len >= 3) {
+		a += k[0];
+		b += k[1];
+		c += k[2];
+		__jhash_mix(a, b, c);
+		k += 3;
+		len -= 3;
+	}
+
+	c += length * 4;
+
+	switch (len) {
+	case 2:
+		b += k[1];
+	/* fallthru */
+	case 1:
+		a += k[0];
+	}
+
+	__jhash_mix(a, b, c);
+
+	return c;
+}
+
+
+/* A special ultra-optimized versions that knows they are hashing exactly
+ * 3, 2 or 1 word(s).
+ *
+ * NOTE: In partilar the "c += length; __jhash_mix(a,b,c);" normally
+ *       done at the end is not done here.
+ */
+uint32_t jhash_3words(uint32_t a, uint32_t b, uint32_t c, uint32_t initval)
+{
+	a += JHASH_GOLDEN_RATIO;
+	b += JHASH_GOLDEN_RATIO;
+	c += initval;
+
+	__jhash_mix(a, b, c);
+
+	return c;
+}
+
+uint32_t jhash_2words(uint32_t a, uint32_t b, uint32_t initval)
+{
+	return jhash_3words(a, b, 0, initval);
+}
+
+uint32_t jhash_1word(uint32_t a, uint32_t initval)
+{
+	return jhash_3words(a, 0, 0, initval);
+}