typedef struct Payload Payload;
struct Payload {
- void *Data;
- DeleteHashDataFunc Destructor;
+ /**
+ * \brief Hash Payload storage Structure; filled in linear.
+ */
+ void *Data; /**< the Data belonging to this storage */
+ DeleteHashDataFunc Destructor; /**< if we want to destroy Data, do it with this function. */
};
struct HashKey {
- long Key;
- long Position;
- char *HashKey;
- long HKLen;
+ /**
+ * \brief Hash key element; sorted by Keye
+ */
+ long Key; /**< Numeric Hashkey comperator for hash sorting */
+ long Position; /**< Pointer to a Payload struct in the Payload Aray */
+ char *HashKey; /**< the Plaintext Hashkey */
+ long HKLen; /**< length of the Plaintext Hashkey */
+ Payload *PL; /**< pointer to our payload for sorting */
};
struct HashList {
- Payload **Members;
- HashKey **LookupTable;
- char **MyKeys;
- long nMembersUsed;
- long MemberSize;
+ /**
+ * \brief Hash structure; holds arrays of Hashkey and Payload.
+ */
+ Payload **Members; /**< Our Payload members. This fills up linear */
+ HashKey **LookupTable; /**< Hash Lookup table. Elements point to members, and are sorted by their hashvalue */
+ char **MyKeys; /**< this keeps the members for a call of GetHashKeys */
+ long nMembersUsed; /**< how many pointers inside of the array are used? */
+ long MemberSize; /**< how big is Members and LookupTable? */
+ long tainted; /**< if 0, we're hashed, else s.b. else sorted us in his own way. */
};
struct HashPos {
+ /**
+ * \brief Anonymous Hash Iterator Object. used for traversing the whole array from outside
+ */
long Position;
};
-#define DEBUG
+
+/**
+ * \brief verify the contents of a hash list; here for debugging purposes.
+ * \param Hash your Hashlist structure
+ * \param First Functionpointer to allow you to print your payload
+ * \param Second Functionpointer to allow you to print your payload
+ * \returns 0
+ */
int PrintHash(HashList *Hash, PrintHashContent First, PrintHashContent Second)
{
const char *foo;
}
-
+/**
+ * \brief instanciate a new hashlist
+ * \returns the newly allocated list.
+ */
HashList *NewHash(void)
{
HashList *NewList;
memset(NewList->LookupTable, 0, sizeof(HashKey*) * 100);
NewList->MemberSize = 100;
+ NewList->tainted = 0;
return NewList;
}
-
+/**
+ * \brief private destructor for one hash element.
+ * \param Data an element to free using the user provided destructor, or just plain free
+ */
static void DeleteHashPayload (Payload *Data)
{
+ /** do we have a destructor for our payload? */
if (Data->Destructor)
Data->Destructor(Data->Data);
else
free(Data->Data);
}
+
+/**
+ * \brief destroy a hashlist and all of its members
+ * \param Hash Hash to destroy. Is NULL'ed so you are shure its done.
+ */
void DeleteHash(HashList **Hash)
{
int i;
return;
for (i=0; i < FreeMe->nMembersUsed; i++)
{
+ /** get rid of our payload */
if (FreeMe->Members[i] != NULL)
{
DeleteHashPayload(FreeMe->Members[i]);
free(FreeMe->Members[i]);
}
+ /** delete our hashing data */
if (FreeMe->LookupTable[i] != NULL)
{
free(FreeMe->LookupTable[i]->HashKey);
free(FreeMe->LookupTable[i]);
}
}
-
+ /** now, free our arrays... */
free(FreeMe->LookupTable);
free(FreeMe->Members);
+ /** did s.b. want an array of our keys? free them. */
if (FreeMe->MyKeys != NULL)
free(FreeMe->MyKeys);
-
+ /** buye bye cruel world. */
free (FreeMe);
*Hash = NULL;
}
+
+/**
+ * \brief private function to add a new item to / replace an existing in - the hashlist
+ * if the hash list is full, its re-alloced with double size.
+ * \parame Hash our hashlist to manipulate
+ * \param HashPos where should we insert / replace?
+ * \param HashKeyStr the Hash-String
+ * \param HKLen length of HashKeyStr
+ * \param Data your Payload to add
+ * \param Destructor Functionpointer to free Data. if NULL, default free() is used.
+ */
static void InsertHashItem(HashList *Hash,
long HashPos,
long HashBinKey,
Payload **NewPayloadArea;
HashKey **NewTable;
+ /** double our payload area */
NewPayloadArea = (Payload**) malloc(sizeof(Payload*) * Hash->MemberSize * 2);
memset(&NewPayloadArea[Hash->MemberSize], 0, sizeof(Payload*) * Hash->MemberSize);
memcpy(NewPayloadArea, Hash->Members, sizeof(Payload*) * Hash->MemberSize);
free(Hash->Members);
Hash->Members = NewPayloadArea;
+ /** double our hashtable area */
NewTable = malloc(sizeof(HashKey*) * Hash->MemberSize * 2);
memset(&NewTable[Hash->MemberSize], 0, sizeof(HashKey*) * Hash->MemberSize);
memcpy(NewTable, Hash->LookupTable, sizeof(HashKey*) * Hash->MemberSize);
Hash->MemberSize *= 2;
}
-
+ /** Arrange the payload */
NewPayloadItem = (Payload*) malloc (sizeof(Payload));
NewPayloadItem->Data = Data;
NewPayloadItem->Destructor = Destructor;
-
+ /** Arrange the hashkey */
NewHashKey = (HashKey*) malloc (sizeof(HashKey));
NewHashKey->HashKey = (char *) malloc (HKLen + 1);
NewHashKey->HKLen = HKLen;
memcpy (NewHashKey->HashKey, HashKeyStr, HKLen + 1);
NewHashKey->Key = HashBinKey;
+ NewHashKey->PL = NewPayloadItem;
+ /** our payload is queued at the end... */
NewHashKey->Position = Hash->nMembersUsed;
-
+ /** but if we should be sorted into a specific place... */
if ((Hash->nMembersUsed != 0) &&
(HashPos != Hash->nMembersUsed) ) {
long InsertAt;
ItemsAfter = Hash->nMembersUsed - HashPos;
InsertAt = HashPos;
-
+ /** make space were we can fill us in */
if (ItemsAfter > 0)
{
memmove(&Hash->LookupTable[InsertAt + 1],
ItemsAfter * sizeof(HashKey*));
}
}
-
+
Hash->Members[Hash->nMembersUsed] = NewPayloadItem;
Hash->LookupTable[HashPos] = NewHashKey;
Hash->nMembersUsed++;
}
+/**
+ * \brief if the user has tainted the hash, but wants to insert / search items by their key
+ * we need to search linear through the array. You have been warned that this will take more time!
+ * \param Hash Our Hash to manipulate
+ * \param HashBinKey the Hash-Number to lookup.
+ * \returns the position (most closely) matching HashBinKey (-> Caller needs to compare! )
+ */
+static long FindInTaintedHash(HashList *Hash, long HashBinKey)
+{
+ long SearchPos;
+
+ for (SearchPos = 0; SearchPos < Hash->nMembersUsed; SearchPos ++) {
+ if (Hash->LookupTable[SearchPos]->Key == HashBinKey){
+ return SearchPos;
+ }
+ }
+ return SearchPos;
+}
+
+/**
+ * \brief Private function to lookup the Item / the closest position to put it in
+ * \param Hash Our Hash to manipulate
+ * \param HashBinKey the Hash-Number to lookup.
+ * \returns the position (most closely) matching HashBinKey (-> Caller needs to compare! )
+ */
static long FindInHash(HashList *Hash, long HashBinKey)
{
long SearchPos;
long StepWidth;
+ if (Hash->tainted)
+ return FindInTaintedHash(Hash, HashBinKey);
+
SearchPos = Hash->nMembersUsed / 2;
StepWidth = SearchPos / 2;
while ((SearchPos > 0) &&
return SearchPos;
}
-
-
+/**
+ * \brief private abstract wrapper around the hashing algorithm
+ * \param HKey the hash string
+ * \param HKLen length of HKey
+ * \returns the calculated hash value
+ */
inline static long CalcHashKey (char *HKey, long HKLen)
{
return hashlittle(HKey, HKLen, 9283457);
}
+/**
+ * \brief Add a new / Replace an existing item in the Hash
+ * \param HashList the list to manipulate
+ * \param HKey the hash-string to store Data under
+ * \param HKeyLen Length of HKey
+ * \param Data the payload you want to associate with HKey
+ * \param DeleteIt if not free() should be used to delete Data set to NULL, else DeleteIt is used.
+ */
void Put(HashList *Hash, char *HKey, long HKLen, void *Data, DeleteHashDataFunc DeleteIt)
{
long HashBinKey;
long HashAt;
-
+ /** first, find out were we could fit in... */
HashBinKey = CalcHashKey(HKey, HKLen);
HashAt = FindInHash(Hash, HashBinKey);
+ /** oh, we're brand new... */
if (Hash->LookupTable[HashAt] == NULL){
InsertHashItem(Hash, HashAt, HashBinKey, HKey, HKLen, Data, DeleteIt);
- }
+ }/** Insert After? */
else if (Hash->LookupTable[HashAt]->Key > HashBinKey) {
InsertHashItem(Hash, HashAt, HashBinKey, HKey, HKLen, Data, DeleteIt);
- }
+ }/** Insert before? */
else if (Hash->LookupTable[HashAt]->Key < HashBinKey) {
InsertHashItem(Hash, HashAt + 1, HashBinKey, HKey, HKLen, Data, DeleteIt);
}
- else { /* Ok, we have a colision. replace it. */
+ else { /** Ok, we have a colision. replace it. */
long PayloadPos;
PayloadPos = Hash->LookupTable[HashAt]->Position;
}
}
+/**
+ * \brief Lookup the Data associated with HKey
+ * \param Hash the Hashlist to search in
+ * \param HKey the hashkey to look up
+ * \param HKLen length of HKey
+ * \param Data returns the Data associated with HKey
+ * \returns 0 if not found, 1 if.
+ */
int GetHash(HashList *Hash, const char *HKey, long HKLen, void **Data)
{
long HashBinKey;
long HashAt;
+ /** first, find out were we could be... */
HashBinKey = CalcHashKey((char*)HKey, HKLen);
HashAt = FindInHash(Hash, HashBinKey);
- if ((HashAt < 0) ||
- (HashAt >= Hash->nMembersUsed) ||
- (Hash->LookupTable[HashAt]->Key != 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? */
*Data = NULL;
return 0;
}
- else {
+ else { /** GOTCHA! */
long MemberPosition;
MemberPosition = Hash->LookupTable[HashAt]->Position;
}
}
+/* TODO? */
int GetKey(HashList *Hash, char *HKey, long HKLen, void **Payload)
{
return 0;
}
+/**
+ * \brief get the Keys present in this hash, simila to array_keys() in PHP
+ * Attention: List remains to Hash! don't modify or free it!
+ * \param Hash Your Hashlist to extract the keys from
+ * \param List returns the list of hashkeys stored in Hash
+ */
int GetHashKeys(HashList *Hash, char ***List)
{
long i;
return Hash->nMembersUsed;
}
+/**
+ * \brief creates a hash-linear iterator object
+ * \returns the hash iterator
+ */
HashPos *GetNewHashPos(void)
{
HashPos *Ret;
return Ret;
}
+/**
+ * \brief frees a linear hash iterator
+ */
void DeleteHashPos(HashPos **DelMe)
{
free(*DelMe);
*DelMe = NULL;
}
+
+/**
+ * \brief Get the data located where HashPos Iterator points at, and Move HashPos one forward
+ * \param Hash your Hashlist to follow
+ * \param HKLen returns Length of Hashkey Returned
+ * \param HashKey returns the Hashkey corrosponding to HashPos
+ * \param Data returns the Data found at HashPos
+ * \returns whether the item was found or not.
+ */
int GetNextHashPos(HashList *Hash, HashPos *At, long *HKLen, char **HashKey, void **Data)
{
long PayloadPos;
At->Position++;
return 1;
}
+
+/**
+ * \brief sorting function for sorting the Hash alphabeticaly by their strings
+ * \param Key1 first item
+ * \param Key2 second item
+ */
+static int SortByKeys(const void *Key1, const void* Key2)
+{
+ HashKey *HKey1, *HKey2;
+ HKey1 = *(HashKey**) Key1;
+ HKey2 = *(HashKey**) Key2;
+
+ return strcasecmp(HKey1->HashKey, HKey2->HashKey);
+}
+
+/**
+ * \brief sorting function to regain hash-sequence and revert tainted status
+ * \param Key1 first item
+ * \param Key2 second item
+ */
+static int SortByHashKeys(const void *Key1, const void* Key2)
+{
+ HashKey *HKey1, *HKey2;
+ HKey1 = *(HashKey**) Key1;
+ HKey2 = *(HashKey**) Key2;
+
+ return HKey1->Key > HKey2->Key;
+}
+
+
+/**
+ * \brief sort the hash alphabeticaly by their keys.
+ * Caution: This taints the hashlist, so accessing it later
+ * will be significantly slower! You can un-taint it by SortByHashKeyStr
+ * \param Hash the list to sort
+ */
+void SortByHashKey(HashList *Hash)
+{
+ if (Hash->nMembersUsed < 2)
+ return;
+ qsort(Hash->LookupTable, Hash->nMembersUsed, sizeof(HashKey*), SortByKeys);
+ Hash->tainted = 1;
+}
+
+/**
+ * \brief sort the hash by their keys (so it regains untainted state).
+ * this will result in the sequence the hashing allgorithm produces it by default.
+ * \param Hash the list to sort
+ */
+void SortByHashKeyStr(HashList *Hash)
+{
+ Hash->tainted = 0;
+ if (Hash->nMembersUsed < 2)
+ return;
+ qsort(Hash->LookupTable, Hash->nMembersUsed, sizeof(HashKey*), SortByHashKeys);
+}
+
+
+/**
+ * \brief gives user sort routines access to the hash payload
+ * \param Searchentry to retrieve Data to
+ * \returns Data belonging to HashVoid
+ */
+const void *GetSearchPayload(const void *HashVoid)
+{
+ return (*(HashKey**)HashVoid)->PL->Data;
+}
+
+/**
+ * \brief sort the hash by your sort function. see the following sample.
+ * this will result in the sequence the hashing allgorithm produces it by default.
+ * \param Hash the list to sort
+ * \param SortBy Sortfunction; see below how to implement this
+ */
+void SortByPayload(HashList *Hash, CompareFunc SortBy)
+{
+ if (Hash->nMembersUsed < 2)
+ return;
+ qsort(Hash->LookupTable, Hash->nMembersUsed, sizeof(HashKey*), SortBy);
+ Hash->tainted = 1;
+}
+
+
+
+
+/**
+ * given you've put char * into your hash as a payload, a sort function might
+ * look like this:
+ * int SortByChar(const void* First, const void* Second)
+ * {
+ * char *a, *b;
+ * a = (char*) GetSearchPayload(First);
+ * b = (char*) GetSearchPayload(Second);
+ * return strcmp (a, b);
+ * }
+ */
projects / citadel.git / commitdiff