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cc65/src/common/hashtab.h
Greg King 0390c34e88 Changed multi-line C comments into another style.
The left side doesn't look unbalanced.
2014-06-30 16:51:07 -04:00

180 lines
7.0 KiB
C

/*****************************************************************************/
/* */
/* hashtab.h */
/* */
/* Generic hash table */
/* */
/* */
/* */
/* (C) 2003-2011, Ullrich von Bassewitz */
/* Roemerstrasse 52 */
/* D-70794 Filderstadt */
/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
/* warranty. In no event will the authors be held liable for any damages */
/* arising from the use of this software. */
/* */
/* Permission is granted to anyone to use this software for any purpose, */
/* including commercial applications, and to alter it and redistribute it */
/* freely, subject to the following restrictions: */
/* */
/* 1. The origin of this software must not be misrepresented; you must not */
/* claim that you wrote the original software. If you use this software */
/* in a product, an acknowledgment in the product documentation would be */
/* appreciated but is not required. */
/* 2. Altered source versions must be plainly marked as such, and must not */
/* be misrepresented as being the original software. */
/* 3. This notice may not be removed or altered from any source */
/* distribution. */
/* */
/*****************************************************************************/
#ifndef HASHTAB_H
#define HASHTAB_H
/* common */
#include "inline.h"
#include "xmalloc.h"
/*****************************************************************************/
/* Data */
/*****************************************************************************/
/* Hash table node. NOTE: This structure must be the first member of a struct
** that is hashed by the module. Having it first allows to omit a pointer to
** the entry itself, because the C standard guarantees that a pointer to a
** struct can be converted to its first member.
*/
typedef struct HashNode HashNode;
struct HashNode {
HashNode* Next; /* Next entry in hash list */
unsigned Hash; /* The full hash value */
};
#define STATIC_HASHNODE_INITIALIZER { 0, 0, 0 }
/* Hash table functions */
typedef struct HashFunctions HashFunctions;
struct HashFunctions {
unsigned (*GenHash) (const void* Key);
/* Generate the hash over a key. */
const void* (*GetKey) (const void* Entry);
/* Given a pointer to the user entry data, return a pointer to the key */
int (*Compare) (const void* Key1, const void* Key2);
/* Compare two keys. The function must return a value less than zero if
** Key1 is smaller than Key2, zero if both are equal, and a value greater
** than zero if Key1 is greater then Key2.
*/
};
/* Hash table */
typedef struct HashTable HashTable;
struct HashTable {
unsigned Slots; /* Number of table slots */
unsigned Count; /* Number of table entries */
HashNode** Table; /* Table, dynamically allocated */
const HashFunctions* Func; /* Table functions */
};
#define STATIC_HASHTABLE_INITIALIZER(Slots, Func) { Slots, 0, 0, Func }
/*****************************************************************************/
/* struct HashNode */
/*****************************************************************************/
#if defined(HAVE_INLINE)
INLINE void InitHashNode (HashNode* N)
/* Initialize a hash node. */
{
N->Next = 0;
}
#else
#define InitHashNode(N) do { (N)->Next = 0; } while (0)
#endif
/*****************************************************************************/
/* struct HashTable */
/*****************************************************************************/
HashTable* InitHashTable (HashTable* T, unsigned Slots, const HashFunctions* Func);
/* Initialize a hash table and return it */
void DoneHashTable (HashTable* T);
/* Destroy the contents of a hash table. Note: This will not free the entries
** in the table!
*/
#if defined(HAVE_INLINE)
INLINE HashTable* NewHashTable (unsigned Slots, const HashFunctions* Func)
/* Create a new hash table and return it. */
{
/* Allocate memory, initialize and return it */
return InitHashTable (xmalloc (sizeof (HashTable)), Slots, Func);
}
#else
#define NewHashTable(Slots, Func) InitHashTable(xmalloc (sizeof (HashTable)), Slots, Func)
#endif
void FreeHashTable (HashTable* T);
/* Free a hash table. Note: This will not free the entries in the table! */
#if defined(HAVE_INLINE)
INLINE unsigned HT_GetCount (const HashTable* T)
/* Return the number of items in the table. */
{
return T->Count;
}
#else
#define HT_GetCount(T) ((T)->Count)
#endif
HashNode* HT_FindHash (const HashTable* T, const void* Key, unsigned Hash);
/* Find the node with the given key. Differs from HT_Find in that the hash
** for the key is precalculated and passed to the function.
*/
void* HT_Find (const HashTable* T, const void* Key);
/* Find the entry with the given key and return it */
void HT_Insert (HashTable* T, void* Entry);
/* Insert an entry into the given hash table */
void HT_Remove (HashTable* T, void* Entry);
/* Remove an entry from the given hash table */
void HT_Walk (HashTable* T, int (*F) (void* Entry, void* Data), void* Data);
/* Walk over all nodes of a hash table, optionally deleting entries from the
** table. For each node, the user supplied function F is called, passing a
** pointer to the entry, and the data pointer passed to HT_Walk by the caller.
** If F returns true, the node is deleted from the hash table otherwise it's
** left in place. While deleting the node, the node is not accessed, so it is
** safe for F to free the memory associcated with the entry.
*/
/* End of hashtab.h */
#endif