From e5cc417e96d37741b0d22edda63b73a87195e0a6 Mon Sep 17 00:00:00 2001
From: Julien BLACHE <jb@jblache.org>
Date: Thu, 30 Apr 2009 14:51:36 +0200
Subject: [PATCH] Add DJB hash function to misc.[ch] and use it

---
 src/httpd_daap.c |  6 ++----
 src/main.c       |  5 +++--
 src/misc.c       | 16 ++++++++++++++++
 src/misc.h       |  5 +++++
 4 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/src/httpd_daap.c b/src/httpd_daap.c
index c572a7e8..5ccf4fa3 100644
--- a/src/httpd_daap.c
+++ b/src/httpd_daap.c
@@ -47,8 +47,6 @@
 #include "httpd.h"
 #include "httpd_daap.h"
 
-#include "util.h"
-
 
 struct uri_map {
   regex_t preg;
@@ -691,7 +689,7 @@ parse_meta(struct evhttp_request *req, char *tag, const char *param, uint32_t **
   meta = strtok_r(metastr, ",", &ptr);
   for (i = 0; i < nmeta; i++)
     {
-      hashes[i] = util_djb_hash_str(meta);
+      hashes[i] = djb_hash(meta, strlen(meta));
 
       meta = strtok_r(NULL, ",", &ptr);
       if (!meta)
@@ -1939,7 +1937,7 @@ daap_init(void)
 
   for (i = 0; dmap_fields[i].type != 0; i++)
     {
-      dmap_fields[i].hash = util_djb_hash_str(dmap_fields[i].desc);
+      dmap_fields[i].hash = djb_hash(dmap_fields[i].desc, strlen(dmap_fields[i].desc));
 
       node = avl_insert(dmap_fields_hash, &dmap_fields[i]);
       if (!node)
diff --git a/src/main.c b/src/main.c
index 3a0a0979..9c506df2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -86,6 +86,7 @@
 #include "conf.h"
 #include "configfile.h"
 #include "err.h"
+#include "misc.h"
 #include "filescanner.h"
 #include "httpd.h"
 #include "webserver.h"
@@ -702,8 +703,8 @@ int main(int argc, char *argv[]) {
       }
 
     snprintf(txtrecord[0], 128, "txtvers=1");
-    snprintf(txtrecord[1], 128, "Database ID=%0X", util_djb_hash_str(servername));
-    snprintf(txtrecord[2], 128, "Machine ID=%0X", util_djb_hash_str(servername));
+    snprintf(txtrecord[1], 128, "Database ID=%0X", djb_hash(servername, strlen(servername)));
+    snprintf(txtrecord[2], 128, "Machine ID=%0X", djb_hash(servername, strlen(servername)));
     snprintf(txtrecord[3], 128, "Machine Name=%s", servername);
     snprintf(txtrecord[4], 128, "mtd-version=%s", VERSION);
     snprintf(txtrecord[5], 128, "iTSh Version=131073"); /* iTunes 6.0.4 */
diff --git a/src/misc.c b/src/misc.c
index b5c01069..87f6dbaf 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -23,6 +23,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <stdint.h>
 #include <limits.h>
 
 #include "daapd.h"
@@ -94,3 +95,18 @@ safe_atol(const char *str, long *val)
 
   return 0;
 }
+
+uint32_t
+djb_hash(void *data, size_t len)
+{
+  unsigned char *bytes = data;
+  uint32_t hash = 5381;
+
+  while (len--)
+    {
+      hash = ((hash << 5) + hash) + *bytes;
+      bytes++;
+    }
+
+  return hash;
+}
diff --git a/src/misc.h b/src/misc.h
index 06ef6646..4f4f2748 100644
--- a/src/misc.h
+++ b/src/misc.h
@@ -2,10 +2,15 @@
 #ifndef __MISC_H__
 #define __MISC_H__
 
+#include <stdint.h>
+
 int
 safe_atoi(const char *str, int *val);
 
 int
 safe_atol(const char *str, long *val);
 
+uint32_t
+djb_hash(void *data, size_t len);
+
 #endif /* !__MISC_H__ */