bk commit into 4.1 tree (jimw:1.2303) BUG#10931

[Jim Winstead]

Below is the list of changes that have just been committed into a local
4.1 repository of jimw. When jimw does a push these changes will
be propagated to the main repository and, within 24 hours after the
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ChangeSet
  1.2303 05/06/01 11:30:59 jimw@stripped +1 -0
  Fix hashcmp() to handle special case of zero length, which
  resulted in the hostname cache being ineffective. Based on
  patch from Jeremy Cole of Yahoo! (Bug #10931)

  mysys/hash.c
    1.43 05/06/01 11:30:56 jimw@stripped +20 -2
    Fix hashcmp() to handle length == 0 as in 4.0, and document the
    function, including this special case.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	jimw
# Host:	rama.(none)
# Root:	/home/jimw/my/mysql-4.1-10931

--- 1.42/mysys/hash.c	2005-03-07 01:27:17 -08:00
+++ 1.43/mysys/hash.c	2005-06-01 11:30:56 -07:00
@@ -262,7 +262,25 @@
   return;
 }
 
-	/* Compare a key in a record to a whole key. Return 0 if identical */
+/*
+  Compare a key in a record to a whole key. Return 0 if identical
+
+  SYNOPSIS
+    hashcmp()
+    hash   hash table
+    pos    position of hash record to use in comparison
+    key    key for comparison
+    length length of key
+
+  NOTES:
+    If length is 0, comparison is done using the length of the
+    record being compared against.
+
+  RETURN
+    < 0  key of record <  key
+    = 0  key of record == key
+    > 0  key of record >  key
+ */
 
 static int hashcmp(HASH *hash,HASH_LINK *pos,const byte *key,uint length)
 {
@@ -270,7 +288,7 @@
   byte *rec_key= (byte*) hash_key(hash,pos->data,&rec_keylength,1);
   return ((length && length != rec_keylength) ||
 	  my_strnncoll(hash->charset, (uchar*) rec_key, rec_keylength,
-		       (uchar*) key, length));
+		       (uchar*) key, rec_keylength));
 }