From 6317f6941770e6b9b21d5fb1e0053cb1d3fb1a46 Mon Sep 17 00:00:00 2001
From: Dave West <davew@uncensored.citadel.org>
Date: Thu, 3 Dec 2009 20:00:03 +0000
Subject: [PATCH] For peer review. Added two new hash manipulation functions.
 int SetHashPosFromKey(HashList *Hash, const char *HKey, long HKLen, HashPos
 *At); int DeleteEntryFromHash(HashList *Hash, HashPos *At);

First one searches for the Key and updates the HashPos to point at it.
Second one deletes an entry from the hash, entry is pointed to by HashPos
---
 libcitadel/lib/hash.c       | 65 +++++++++++++++++++++++++++++++++++++
 libcitadel/lib/libcitadel.h |  2 ++
 2 files changed, 67 insertions(+)

diff --git a/libcitadel/lib/hash.c b/libcitadel/lib/hash.c
index be29055a1..33e3cfade 100644
--- a/libcitadel/lib/hash.c
+++ b/libcitadel/lib/hash.c
@@ -584,6 +584,71 @@ HashPos *GetNewHashPos(HashList *Hash, int StepWidth)
 	return Ret;
 }
 
+/**
+ * @brief Set iterator object to point to key. If not found, don't change iterator
+ * @param Hash the list we reference
+ * @param HKey key to search for
+ * @param HKLen length of key
+ * @param At HashPos to update
+ * \returns 0 if not found
+ */
+int SetHashPosFromKey(HashList *Hash, const char *HKey, long HKLen, HashPos *At)
+{
+	long HashBinKey;
+	long HashAt;
+
+	if (Hash == NULL)
+		return 0;
+
+	if (HKLen <= 0) {
+		return  0;
+	}
+	/** first, find out were we could be... */
+	HashBinKey = CalcHashKey(Hash, HKey, HKLen);
+	HashAt = FindInHash(Hash, HashBinKey);
+	if ((HashAt < 0) || /**< Not found at the lower edge? */
+	    (HashAt >= Hash->nMembersUsed) || /**< Not found at the upper edge? */
+	    (Hash->LookupTable[HashAt]->Key != HashBinKey)) { /**< somewhere inbetween but no match? */
+		return 0;
+	}
+	/** GOTCHA! */
+	At->Position = Hash->LookupTable[HashAt]->Position;
+	return 1;
+}
+
+/**
+ * @brief Delete from the Hash the entry at Position
+ * @param Hash the list we reference
+ * @param At the position within the Hash
+ * \returns 0 if not found
+ */
+int DeleteEntryFromHash(HashList *Hash, HashPos *At)
+{
+	if (Hash == NULL)
+		return 0;
+
+	if ((Hash == NULL) || 
+	    (At->Position >= Hash->nMembersUsed) || 
+	    (At->Position < 0) ||
+	    (At->Position > Hash->nMembersUsed))
+		return 0;
+	/** get rid of our payload */
+	if (Hash->Members[At->Position] != NULL)
+	{
+		DeleteHashPayload(Hash->Members[At->Position]);
+		free(Hash->Members[At->Position]);
+		Hash->Members[At->Position] = NULL;
+	}
+	/** delete our hashing data */
+	if (Hash->LookupTable[At->Position] != NULL)
+	{
+		free(Hash->LookupTable[At->Position]->HashKey);
+		free(Hash->LookupTable[At->Position]);
+		Hash->LookupTable[At->Position] = NULL;
+	}
+	return 1;
+}
+
 /**
  * @brief retrieve the counter from the itteratoor
  * @param the Iterator to analyze
diff --git a/libcitadel/lib/libcitadel.h b/libcitadel/lib/libcitadel.h
index 258d76045..f76fd9e75 100644
--- a/libcitadel/lib/libcitadel.h
+++ b/libcitadel/lib/libcitadel.h
@@ -447,6 +447,8 @@ int GetHashKeys(HashList *Hash, char ***List);
 int dbg_PrintHash(HashList *Hash, PrintHashContent first, PrintHashContent Second);
 int PrintHash(HashList *Hash, TransitionFunc Trans, PrintHashDataFunc PrintEntry);
 HashPos *GetNewHashPos(HashList *Hash, int StepWidth);
+int SetHashPosFromKey(HashList *Hash, const char *HKey, long HKLen, HashPos *At);
+int DeleteEntryFromHash(HashList *Hash, HashPos *At);
 int GetHashPosCounter(HashList *Hash, HashPos *At);
 void DeleteHashPos(HashPos **DelMe);
 int GetNextHashPos(HashList *Hash, HashPos *At, long *HKLen, const char **HashKey, void **Data);
-- 
2.30.2