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Switch to djb2 hash function and shut up compiler warnings

Subversion-branch: /trunk/chocolate-doom
Subversion-revision: 908

--- a/src/w_wad.c

+++ b/src/w_wad.c

@@ -98,25 +98,21 @@

 }

 // Hash function used for lump names.

-// Must be mod'ed with table size.

-// Can be used for any 8-character names.

-// by Lee Killough

 unsigned int W_LumpNameHash(const char *s)

 {

-  unsigned int hash;

+    // This is the djb2 string hash function, modded to work on strings

+    // that have a maximum length of 8.

-  ((hash =        toupper(s[0]), s[1]) &&

-   (hash = hash*3+toupper(s[1]), s[2]) &&

-   (hash = hash*2+toupper(s[2]), s[3]) &&

-   (hash = hash*2+toupper(s[3]), s[4]) &&

-   (hash = hash*2+toupper(s[4]), s[5]) &&

-   (hash = hash*2+toupper(s[5]), s[6]) &&

-   (hash = hash*2+toupper(s[6]),

-    hash = hash*2+toupper(s[7]))

-  );

+    unsigned int result = 5381;

+    unsigned int i;

-  return hash;

+    for (i=0; i < 8 && s[i] != '\0'; ++i)

+    {

+        result = ((result << 5) ^ result ) ^ toupper(s[i]);

+    }

+

+    return result;

 }

 //