commit c447a5da8c8087d94867560764b59f03d0e70b1d
Author: Simon Howard <fraggle@gmail.com>
AuthorDate: Sat Jun 16 16:02:46 2007 +0000
Commit: Simon Howard <fraggle@gmail.com>
CommitDate: Sat Jun 16 16:02:46 2007 +0000
Switch to djb2 hash function and shut up compiler warnings
Subversion-branch: /trunk/chocolate-doom
Subversion-revision: 908
---
src/w_wad.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)
diff --git a/src/w_wad.c b/src/w_wad.c
index 892086d7..598794c4 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -98,25 +98,21 @@ static void ExtractFileBase(char *path, char *dest)
}
// 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;
-
- ((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]))
- );
-
- return hash;
+ // This is the djb2 string hash function, modded to work on strings
+ // that have a maximum length of 8.
+
+ unsigned int result = 5381;
+ unsigned int i;
+
+ for (i=0; i < 8 && s[i] != '\0'; ++i)
+ {
+ result = ((result << 5) ^ result ) ^ toupper(s[i]);
+ }
+
+ return result;
}
//