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Viewing changes to libkmod/libkmod-hash.c

  • Committer: Package Import Robot
  • Author(s): Adam Conrad
  • Date: 2012-09-21 16:05:32 UTC
  • mfrom: (4.1.7 sid)
  • Revision ID: package-import@ubuntu.com-20120921160532-bdsxhmpj5og2ru5h
Tags: 9-2ubuntu1
* Sync with Debian unstable; remaining Ubuntu changes:
  - Ubuntu-specific depmod.d and modprobe.d contents.
  - Mark module-init-tools Multi-Arch: foreign.
  - Don't install Debian's extra/aliases.conf file.
  - Install upstart job instead of the sysvinit script.

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libkmod/libkmod-hash.c
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#include "libkmod.h"
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#include "libkmod-hash.h"
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#include "libkmod-util.h"
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#include <stdlib.h>
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#include <string.h>
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#include <errno.h>
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        free(hash);
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}
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struct unaligned_short {
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    unsigned short v;
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} __attribute__((packed));
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static inline unsigned short get16bits(const char *ptr)
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{
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    return ((struct unaligned_short *)ptr)->v;
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}
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static inline unsigned int hash_superfast(const char *key, unsigned int len)
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{
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        /* Paul Hsieh (http://www.azillionmonkeys.com/qed/hash.html)
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        /* Main loop */
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        for (; len > 0; len--) {
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                hash += get16bits(key);
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                tmp = (get16bits(key + 2) << 11) ^ hash;
 
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                hash += get_unaligned((uint16_t *) key);
 
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                tmp = (get_unaligned((uint16_t *)(key + 2)) << 11) ^ hash;
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                hash = (hash << 16) ^ tmp;
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                key += 4;
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                hash += hash >> 11;
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        /* Handle end cases */
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        switch (rem) {
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        case 3:
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                hash += get16bits(key);
 
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                hash += get_unaligned((uint16_t *) key);
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                hash ^= hash << 16;
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                hash ^= key[2] << 18;
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                hash += hash >> 11;
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                break;
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        case 2:
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                hash += get16bits(key);
 
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                hash += get_unaligned((uint16_t *) key);
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                hash ^= hash << 11;
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                hash += hash >> 17;
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                break;