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 @@
+/*
+ * Copyright (C) 2008 Red Hat, Inc., Jason Baron <jbaron@redhat.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define DYNAMIC_DEBUG_HASH_BITS 6
+
+static const char *program;
+
+static void usage(void)
+{
+        printf("Usage: %s <djb2|r5> <modname>\n", program);
+        exit(1);
+}
+
+/* djb2 hashing algorithm by Dan Bernstein. From:
+ * http://www.cse.yorku.ca/~oz/hash.html
+ */
+
+unsigned int djb2_hash(char *str)
+{
+        unsigned long hash = 5381;
+        int c;
+
+        c = *str;
+        while (c) {
+                hash = ((hash << 5) + hash) + c;
+                c = *++str;
+        }
+        return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
+}
+
+unsigned int r5_hash(char *str)
+{
+        unsigned long hash = 0;
+        int c;
+
+        c = *str;
+        while (c) {
+                hash = (hash + (c << 4) + (c >> 4)) * 11;
+                c = *++str;
+        }
+        return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
+}
+
+int main(int argc, char *argv[])
+{
+        program = argv[0];
+
+        if (argc != 3)
+                usage();
+        if (!strcmp(argv[1], "djb2"))
+                printf("%d\n", djb2_hash(argv[2]));
+        else if (!strcmp(argv[1], "r5"))
+                printf("%d\n", r5_hash(argv[2]));
+        else
+                usage();
+        exit(0);
+}
+