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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-16 15:40:26 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-16 15:40:26 -0400
commitc813b4e16ead3c3df98ac84419d4df2adf33fe01 (patch)
tree2ca4a5b6966d833b6149e3dda7a4e85d1255779c /scripts/basic/hash.c
parentc8d8a2321f9c4ee18fbcc399fdc2a77e580a03b9 (diff)
parent02683ffdf655b4ae15245376ba6fea6d9e5829a6 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (46 commits) UIO: Fix mapping of logical and virtual memory UIO: add automata sercos3 pci card support UIO: Change driver name of uio_pdrv UIO: Add alignment warnings for uio-mem Driver core: add bus_sort_breadthfirst() function NET: convert the phy_device file to use bus_find_device_by_name kobject: Cleanup kobject_rename and !CONFIG_SYSFS kobject: Fix kobject_rename and !CONFIG_SYSFS sysfs: Make dir and name args to sysfs_notify() const platform: add new device registration helper sysfs: use ilookup5() instead of ilookup5_nowait() PNP: create device attributes via default device attributes Driver core: make bus_find_device_by_name() more robust usb: turn dev_warn+WARN_ON combos into dev_WARN debug: use dev_WARN() rather than WARN_ON() in device_pm_add() debug: Introduce a dev_WARN() function sysfs: fix deadlock device model: Do a quickcheck for driver binding before doing an expensive check Driver core: Fix cleanup in device_create_vargs(). Driver core: Clarify device cleanup. ...
Diffstat (limited to 'scripts/basic/hash.c')
-rw-r--r--scripts/basic/hash.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/scripts/basic/hash.c b/scripts/basic/hash.c
new file mode 100644
index 000000000000..3299ad7fc8c0
--- /dev/null
+++ b/scripts/basic/hash.c
@@ -0,0 +1,64 @@
1/*
2 * Copyright (C) 2008 Red Hat, Inc., Jason Baron <jbaron@redhat.com>
3 *
4 */
5
6#include <stdio.h>
7#include <stdlib.h>
8#include <string.h>
9
10#define DYNAMIC_DEBUG_HASH_BITS 6
11
12static const char *program;
13
14static void usage(void)
15{
16 printf("Usage: %s <djb2|r5> <modname>\n", program);
17 exit(1);
18}
19
20/* djb2 hashing algorithm by Dan Bernstein. From:
21 * http://www.cse.yorku.ca/~oz/hash.html
22 */
23
24unsigned int djb2_hash(char *str)
25{
26 unsigned long hash = 5381;
27 int c;
28
29 c = *str;
30 while (c) {
31 hash = ((hash << 5) + hash) + c;
32 c = *++str;
33 }
34 return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
35}
36
37unsigned int r5_hash(char *str)
38{
39 unsigned long hash = 0;
40 int c;
41
42 c = *str;
43 while (c) {
44 hash = (hash + (c << 4) + (c >> 4)) * 11;
45 c = *++str;
46 }
47 return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
48}
49
50int main(int argc, char *argv[])
51{
52 program = argv[0];
53
54 if (argc != 3)
55 usage();
56 if (!strcmp(argv[1], "djb2"))
57 printf("%d\n", djb2_hash(argv[2]));
58 else if (!strcmp(argv[1], "r5"))
59 printf("%d\n", r5_hash(argv[2]));
60 else
61 usage();
62 exit(0);
63}
64