From: Jeff Dike UML needs ghash.h, from 2.4 --- 25-akpm/include/linux/ghash.h | 236 ++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 236 insertions(+) diff -puN /dev/null include/linux/ghash.h --- /dev/null Thu Apr 11 07:25:15 2002 +++ 25-akpm/include/linux/ghash.h Thu Jan 15 17:59:06 2004 @@ -0,0 +1,236 @@ +/* + * include/linux/ghash.h -- generic hashing with fuzzy retrieval + * + * (C) 1997 Thomas Schoebel-Theuer + * + * The algorithms implemented here seem to be a completely new invention, + * and I'll publish the fundamentals in a paper. + */ + +#ifndef _GHASH_H +#define _GHASH_H +/* HASHSIZE _must_ be a power of two!!! */ + + +#define DEF_HASH_FUZZY_STRUCTS(NAME,HASHSIZE,TYPE) \ +\ +struct NAME##_table {\ + TYPE * hashtable[HASHSIZE];\ + TYPE * sorted_list;\ + int nr_entries;\ +};\ +\ +struct NAME##_ptrs {\ + TYPE * next_hash;\ + TYPE * prev_hash;\ + TYPE * next_sorted;\ + TYPE * prev_sorted;\ +}; + +#define DEF_HASH_FUZZY(LINKAGE,NAME,HASHSIZE,TYPE,PTRS,KEYTYPE,KEY,KEYCMP,KEYEQ,HASHFN)\ +\ +LINKAGE void insert_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\ +{\ + int ix = HASHFN(elem->KEY);\ + TYPE ** base = &tbl->hashtable[ix];\ + TYPE * ptr = *base;\ + TYPE * prev = NULL;\ +\ + tbl->nr_entries++;\ + while(ptr && KEYCMP(ptr->KEY, elem->KEY)) {\ + base = &ptr->PTRS.next_hash;\ + prev = ptr;\ + ptr = *base;\ + }\ + elem->PTRS.next_hash = ptr;\ + elem->PTRS.prev_hash = prev;\ + if(ptr) {\ + ptr->PTRS.prev_hash = elem;\ + }\ + *base = elem;\ +\ + ptr = prev;\ + if(!ptr) {\ + ptr = tbl->sorted_list;\ + prev = NULL;\ + } else {\ + prev = ptr->PTRS.prev_sorted;\ + }\ + while(ptr) {\ + TYPE * next = ptr->PTRS.next_hash;\ + if(next && KEYCMP(next->KEY, elem->KEY)) {\ + prev = ptr;\ + ptr = next;\ + } else if(KEYCMP(ptr->KEY, elem->KEY)) {\ + prev = ptr;\ + ptr = ptr->PTRS.next_sorted;\ + } else\ + break;\ + }\ + elem->PTRS.next_sorted = ptr;\ + elem->PTRS.prev_sorted = prev;\ + if(ptr) {\ + ptr->PTRS.prev_sorted = elem;\ + }\ + if(prev) {\ + prev->PTRS.next_sorted = elem;\ + } else {\ + tbl->sorted_list = elem;\ + }\ +}\ +\ +LINKAGE void remove_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\ +{\ + TYPE * next = elem->PTRS.next_hash;\ + TYPE * prev = elem->PTRS.prev_hash;\ +\ + tbl->nr_entries--;\ + if(next)\ + next->PTRS.prev_hash = prev;\ + if(prev)\ + prev->PTRS.next_hash = next;\ + else {\ + int ix = HASHFN(elem->KEY);\ + tbl->hashtable[ix] = next;\ + }\ +\ + next = elem->PTRS.next_sorted;\ + prev = elem->PTRS.prev_sorted;\ + if(next)\ + next->PTRS.prev_sorted = prev;\ + if(prev)\ + prev->PTRS.next_sorted = next;\ + else\ + tbl->sorted_list = next;\ +}\ +\ +LINKAGE TYPE * find_##NAME##_hash(struct NAME##_table * tbl, KEYTYPE pos)\ +{\ + int ix = hashfn(pos);\ + TYPE * ptr = tbl->hashtable[ix];\ + while(ptr && KEYCMP(ptr->KEY, pos))\ + ptr = ptr->PTRS.next_hash;\ + if(ptr && !KEYEQ(ptr->KEY, pos))\ + ptr = NULL;\ + return ptr;\ +}\ +\ +LINKAGE TYPE * find_##NAME##_hash_fuzzy(struct NAME##_table * tbl, KEYTYPE pos)\ +{\ + int ix;\ + int offset;\ + TYPE * ptr;\ + TYPE * next;\ +\ + ptr = tbl->sorted_list;\ + if(!ptr || KEYCMP(pos, ptr->KEY))\ + return NULL;\ + ix = HASHFN(pos);\ + offset = HASHSIZE;\ + do {\ + offset >>= 1;\ + next = tbl->hashtable[(ix+offset) & ((HASHSIZE)-1)];\ + if(next && (KEYCMP(next->KEY, pos) || KEYEQ(next->KEY, pos))\ + && KEYCMP(ptr->KEY, next->KEY))\ + ptr = next;\ + } while(offset);\ +\ + for(;;) {\ + next = ptr->PTRS.next_hash;\ + if(next) {\ + if(KEYCMP(next->KEY, pos)) {\ + ptr = next;\ + continue;\ + }\ + }\ + next = ptr->PTRS.next_sorted;\ + if(next && KEYCMP(next->KEY, pos)) {\ + ptr = next;\ + continue;\ + }\ + return ptr;\ + }\ + return NULL;\ +} + +/* LINKAGE - empty or "static", depending on whether you want the definitions to + * be public or not + * NAME - a string to stick in names to make this hash table type distinct from + * any others + * HASHSIZE - number of buckets + * TYPE - type of data contained in the buckets - must be a structure, one + * field is of type NAME_ptrs, another is the hash key + * PTRS - TYPE must contain a field of type NAME_ptrs, PTRS is the name of that + * field + * KEYTYPE - type of the key field within TYPE + * KEY - name of the key field within TYPE + * KEYCMP - pointer to function that compares KEYTYPEs to each other - the + * prototype is int KEYCMP(KEYTYPE, KEYTYPE), it returns zero for equal, + * non-zero for not equal + * HASHFN - the hash function - the prototype is int HASHFN(KEYTYPE), + * it returns a number in the range 0 ... HASHSIZE - 1 + * Call DEF_HASH_STRUCTS, define your hash table as a NAME_table, then call + * DEF_HASH. + */ + +#define DEF_HASH_STRUCTS(NAME,HASHSIZE,TYPE) \ +\ +struct NAME##_table {\ + TYPE * hashtable[HASHSIZE];\ + int nr_entries;\ +};\ +\ +struct NAME##_ptrs {\ + TYPE * next_hash;\ + TYPE * prev_hash;\ +}; + +#define DEF_HASH(LINKAGE,NAME,TYPE,PTRS,KEYTYPE,KEY,KEYCMP,HASHFN)\ +\ +LINKAGE void insert_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\ +{\ + int ix = HASHFN(elem->KEY);\ + TYPE ** base = &tbl->hashtable[ix];\ + TYPE * ptr = *base;\ + TYPE * prev = NULL;\ +\ + tbl->nr_entries++;\ + while(ptr && KEYCMP(ptr->KEY, elem->KEY)) {\ + base = &ptr->PTRS.next_hash;\ + prev = ptr;\ + ptr = *base;\ + }\ + elem->PTRS.next_hash = ptr;\ + elem->PTRS.prev_hash = prev;\ + if(ptr) {\ + ptr->PTRS.prev_hash = elem;\ + }\ + *base = elem;\ +}\ +\ +LINKAGE void remove_##NAME##_hash(struct NAME##_table * tbl, TYPE * elem)\ +{\ + TYPE * next = elem->PTRS.next_hash;\ + TYPE * prev = elem->PTRS.prev_hash;\ +\ + tbl->nr_entries--;\ + if(next)\ + next->PTRS.prev_hash = prev;\ + if(prev)\ + prev->PTRS.next_hash = next;\ + else {\ + int ix = HASHFN(elem->KEY);\ + tbl->hashtable[ix] = next;\ + }\ +}\ +\ +LINKAGE TYPE * find_##NAME##_hash(struct NAME##_table * tbl, KEYTYPE pos)\ +{\ + int ix = HASHFN(pos);\ + TYPE * ptr = tbl->hashtable[ix];\ + while(ptr && KEYCMP(ptr->KEY, pos))\ + ptr = ptr->PTRS.next_hash;\ + return ptr;\ +} + +#endif _