/tags/rel-1-3-15/SWIG/Source/DOH/Doh/hash.c
C | 565 lines | 406 code | 64 blank | 95 comment | 71 complexity | 98cd8eb9a48230cab185900d531a8750 MD5 | raw file
Possible License(s): LGPL-2.1, Cube, GPL-3.0, 0BSD, GPL-2.0
- /* -----------------------------------------------------------------------------
- * hash.c
- *
- * Implements a simple hash table object.
- *
- * Author(s) : David Beazley (beazley@cs.uchicago.edu)
- *
- * Copyright (C) 1999-2000. The University of Chicago
- * See the file LICENSE for information on usage and redistribution.
- * ----------------------------------------------------------------------------- */
- static char cvsroot[] = "$Header$";
- #include "dohint.h"
- extern DohObjInfo DohHashType;
- /* Hash node */
- typedef struct HashNode {
- DOH *key;
- DOH *object;
- struct HashNode *next;
- } HashNode;
- /* Hash object */
- typedef struct Hash {
- DOH *file;
- int line;
- HashNode **hashtable;
- int hashsize;
- int currentindex;
- int nitems;
- HashNode *current;
- } Hash;
- /* Key interning structure */
- typedef struct KeyValue {
- char *cstr;
- DOH *sstr;
- struct KeyValue *left;
- struct KeyValue *right;
- } KeyValue;
- static KeyValue *root = 0;
- /* Find or create a key in the interned key table */
- static DOH *find_key (DOH *doh_c) {
- char *c = (char *) doh_c;
- KeyValue *r, *s;
- int d = 0;
- /* OK, sure, we use a binary tree for maintaining interned
- symbols. Then we use their hash values for accessing secondary
- hash tables. */
- r = root;
- s = 0;
- while (r) {
- s = r;
- d = strcmp(r->cstr,c);
- if (d == 0) return r->sstr;
- if (d < 0) r = r->left;
- else r = r->right;
- }
- /* fprintf(stderr,"Interning '%s'\n", c);*/
- r = (KeyValue *) DohMalloc(sizeof(KeyValue));
- r->cstr = (char *) DohMalloc(strlen(c)+1);
- strcpy(r->cstr,c);
- r->sstr = NewString(c);
- DohIntern(r->sstr);
- r->left = 0;
- r->right = 0;
- if (!s) { root = r; }
- else {
- if (d < 0) s->left = r;
- else s->right = r;
- }
- return r->sstr;
- }
- #define HASH_INIT_SIZE 7
- /* Create a new hash node */
- static HashNode *NewNode(DOH *k, void *obj) {
- HashNode *hn = (HashNode *) DohMalloc(sizeof(HashNode));
- hn->key = k;
- Incref(hn->key);
- hn->object = obj;
- Incref(obj);
- hn->next = 0;
- return hn;
- }
- /* Delete a hash node */
- static void DelNode(HashNode *hn) {
- Delete(hn->key);
- Delete(hn->object);
- DohFree(hn);
- }
- /* -----------------------------------------------------------------------------
- * DelHash()
- *
- * Delete a hash table.
- * ----------------------------------------------------------------------------- */
- static void
- DelHash(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- HashNode *n,*next;
- int i;
- for (i = 0; i < h->hashsize; i++) {
- if ((n = h->hashtable[i])) {
- while (n) {
- next = n->next;
- DelNode(n);
- n = next;
- }
- }
- }
- DohFree(h->hashtable);
- h->hashtable = 0;
- h->hashsize = 0;
- DohFree(h);
- }
- /* -----------------------------------------------------------------------------
- * Hash_clear()
- *
- * Clear all of the entries in the hash table.
- * ----------------------------------------------------------------------------- */
- static void
- Hash_clear(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- HashNode *n,*next;
- int i;
- for (i = 0; i < h->hashsize; i++) {
- if ((n = h->hashtable[i])) {
- while (n) {
- next = n->next;
- DelNode(n);
- n = next;
- }
- }
- h->hashtable[i] = 0;
- }
- h->nitems = 0;
- }
- /* resize the hash table */
- static void resize(Hash *h) {
- HashNode *n, *next, **table;
- int oldsize, newsize;
- int i, p, hv;
- if (h->nitems < 2*h->hashsize) return;
- /* Too big. We have to rescale everything now */
- oldsize = h->hashsize;
- /* Calculate a new size */
- newsize = 2*oldsize+1;
- p = 3;
- while (p < (newsize >> 1)) {
- if (((newsize/p)*p) == newsize) {
- newsize+=2;
- p = 3;
- continue;
- }
- p = p + 2;
- }
- table = (HashNode **) DohMalloc(newsize*sizeof(HashNode *));
- for (i = 0; i < newsize; i++ ) {
- table[i] = 0;
- }
- /* Walk down the old set of nodes and re-place */
- h->hashsize = newsize;
- for (i = 0; i < oldsize; i++) {
- n = h->hashtable[i];
- while (n) {
- hv = Hashval(n->key) % newsize;
- next = n->next;
- n->next = table[hv];
- table[hv] = n;
- n = next;
- }
- }
- DohFree(h->hashtable);
- h->hashtable = table;
- }
- /* -----------------------------------------------------------------------------
- * Hash_setattr()
- *
- * Set an attribute in the hash table. Deletes the existing entry if it already
- * exists.
- * ----------------------------------------------------------------------------- */
- static int
- Hash_setattr(DOH *ho, DOH *k, DOH *obj) {
- int hv;
- HashNode *n, *prev;
- Hash *h = (Hash *) ObjData(ho);
-
- if (!obj) {
- return DohDelattr(ho,k);
- }
- if (!DohCheck(k)) k = find_key(k);
- if (!DohCheck(obj)) {
- obj = NewString((char *) obj);
- Decref(obj);
- }
- hv = (Hashval(k)) % h->hashsize;
- n = h->hashtable[hv];
- prev = 0;
- while (n) {
- if (Cmp(n->key,k) == 0) {
- /* Node already exists. Just replace its contents */
- if (n->object == obj) {
- /* Whoa. Same object. Do nothing */
- return 1;
- }
- Delete(n->object);
- n->object = obj;
- Incref(obj);
- return 1; /* Return 1 to indicate a replacement */
- } else {
- prev = n;
- n = n->next;
- }
- }
- /* Add this to the table */
- n = NewNode(k,obj);
- if (prev) prev->next = n;
- else h->hashtable[hv] = n;
- h->nitems++;
- resize(h);
- return 0;
- }
- /* -----------------------------------------------------------------------------
- * Hash_getattr()
- *
- * Get an attribute from the hash table. Returns 0 if it doesn't exist.
- * ----------------------------------------------------------------------------- */
- static DOH *
- Hash_getattr(DOH *ho, DOH *k) {
- int hv;
- HashNode *n;
- Hash *h = (Hash *) ObjData(ho);
- if (!DohCheck(k)) k = find_key(k);
- hv = Hashval(k) % h->hashsize;
- n = h->hashtable[hv];
- while (n) {
- if (Cmp(n->key, k) == 0) return n->object;
- n = n->next;
- }
- return 0;
- }
- /* -----------------------------------------------------------------------------
- * Hash_delattr()
- *
- * Delete an object from the hash table.
- * ----------------------------------------------------------------------------- */
- static int
- Hash_delattr(DOH *ho, DOH *k) {
- HashNode *n, *prev;
- int hv;
- Hash *h = (Hash *) ObjData(ho);
- if (!DohCheck(k)) k = find_key(k);
- hv = Hashval(k) % h->hashsize;
- n = h->hashtable[hv];
- prev = 0;
- while (n) {
- if (Cmp(n->key, k) == 0) {
- /* Found it, kill it */
- if (prev) {
- prev->next = n->next;
- } else {
- h->hashtable[hv] = n->next;
- }
- /* Need to check for iterator location */
- if (n == h->current) {
- h->current = prev; /* Move back to previous node. When next is called, will move to next node */
- if (!h->current) h->currentindex--; /* No previous node. Move back one slot */
- }
- DelNode(n);
- h->nitems--;
- return 1;
- }
- prev = n;
- n = n->next;
- }
- return 0;
- }
- /* General purpose iterators */
- static HashNode *
- hash_first(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- h->currentindex = 0;
- h->current = 0;
- while ((h->currentindex < h->hashsize) && !h->hashtable[h->currentindex])
- h->currentindex++;
- if (h->currentindex >= h->hashsize) return 0;
- h->current = h->hashtable[h->currentindex];
- return h->current;
- }
- static HashNode *
- hash_next(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- if (h->currentindex < 0) return hash_first(ho);
- /* Try to move to the next entry */
- if (h->current) {
- h->current = h->current->next;
- }
- if (h->current) {
- return h->current;
- }
- h->currentindex++;
- while ((h->currentindex < h->hashsize) && !h->hashtable[h->currentindex])
- h->currentindex++;
- if (h->currentindex >= h->hashsize) return 0;
- h->current = h->hashtable[h->currentindex];
- return h->current;
- }
- /* -----------------------------------------------------------------------------
- * Hash_firstkey()
- *
- * Return first hash-table key.
- * ----------------------------------------------------------------------------- */
- static DOH *
- Hash_firstkey(DOH *ho) {
- HashNode *hn = hash_first(ho);
- if (hn) return hn->key;
- return 0;
- }
- /* -----------------------------------------------------------------------------
- * Hash_nextkey()
- *
- * Return next hash table key.
- * ----------------------------------------------------------------------------- */
- static DOH *
- Hash_nextkey(DOH *ho) {
- HashNode *hn = hash_next(ho);
- if (hn) return hn->key;
- return 0;
- }
- /* -----------------------------------------------------------------------------
- * Hash_keys(DOH *)
- *
- * Return a list of keys
- * ----------------------------------------------------------------------------- */
- static DOH *
- Hash_keys(DOH *so) {
- DOH *keys;
- DOH *k;
- keys = NewList();
- k = Firstkey(so);
- while (k) {
- Append(keys,k);
- k = Nextkey(so);
- }
- return keys;
- }
- /* -----------------------------------------------------------------------------
- * Hash_str()
- *
- * Create a string representation of a hash table (mainly for debugging).
- * ----------------------------------------------------------------------------- */
- static DOH *
- Hash_str(DOH *ho) {
- int i,j;
- HashNode *n;
- DOH *s;
- static int indent = 4;
- Hash *h = (Hash *) ObjData(ho);
- s = NewString("");
- if (ObjGetMark(ho)) {
- Printf(s,"Hash(0x%x)",ho);
- return s;
- }
- ObjSetMark(ho,1);
- Printf(s,"Hash {\n");
- for (i = 0; i < h->hashsize; i++) {
- n = h->hashtable[i];
- while (n) {
- for (j = 0; j < indent; j++) Putc(' ',s);
- indent+=4;
- Printf(s,"'%s' : %s, \n", n->key, n->object);
- indent-=4;
- n = n->next;
- }
- }
- for (j = 0; j < (indent-4); j++) Putc(' ',s);
- Printf(s,"}\n");
- ObjSetMark(ho,0);
- return s;
- }
- /* -----------------------------------------------------------------------------
- * Hash_len()
- *
- * Return number of entries in the hash table.
- * ----------------------------------------------------------------------------- */
- static int
- Hash_len(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- return h->nitems;
- }
- /* -----------------------------------------------------------------------------
- * CopyHash()
- *
- * Make a copy of a hash table. Note: this is a shallow copy.
- * ----------------------------------------------------------------------------- */
- static DOH *
- CopyHash(DOH *ho) {
- Hash *h, *nh;
- HashNode *n;
- DOH *nho;
-
- int i;
- h = (Hash *) ObjData(ho);
- nh = (Hash *) DohMalloc(sizeof(Hash));
- nh->hashsize = h->hashsize;
- nh->hashtable = (HashNode **) DohMalloc(nh->hashsize*sizeof(HashNode *));
- for (i = 0; i < nh->hashsize; i++) {
- nh->hashtable[i] = 0;
- }
- nh->currentindex = -1;
- nh->current = 0;
- nh->nitems = 0;
- nh->line = h->line;
- nh->file = h->file;
- if (nh->file) Incref(nh->file);
- nho = DohObjMalloc(&DohHashType, nh);
- for (i = 0; i < h->hashsize; i++) {
- if ((n = h->hashtable[i])) {
- while (n) {
- Hash_setattr(nho, n->key, n->object);
- n = n->next;
- }
- }
- }
- return nho;
- }
- static void
- Hash_setfile(DOH *ho, DOH *file) {
- DOH *fo;
- Hash *h = (Hash *) ObjData(ho);
- if (!DohCheck(file)) {
- fo = NewString(file);
- Decref(fo);
- } else fo = file;
- Incref(fo);
- Delete(h->file);
- h->file = fo;
- }
- static DOH *
- Hash_getfile(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- return h->file;
- }
- static void
- Hash_setline(DOH *ho, int line) {
- Hash *h = (Hash *) ObjData(ho);
- h->line = line;
- }
- static int
- Hash_getline(DOH *ho) {
- Hash *h = (Hash *) ObjData(ho);
- return h->line;
- }
- /* -----------------------------------------------------------------------------
- * type information
- * ----------------------------------------------------------------------------- */
- static DohHashMethods HashHashMethods = {
- Hash_getattr,
- Hash_setattr,
- Hash_delattr,
- Hash_firstkey,
- Hash_nextkey,
- Hash_keys,
- };
- DohObjInfo DohHashType = {
- "Hash", /* objname */
- DelHash, /* doh_del */
- CopyHash, /* doh_copy */
- Hash_clear, /* doh_clear */
- Hash_str, /* doh_str */
- 0, /* doh_data */
- 0, /* doh_dump */
- Hash_len, /* doh_len */
- 0, /* doh_hash */
- 0, /* doh_cmp */
- Hash_setfile, /* doh_setfile */
- Hash_getfile, /* doh_getfile */
- Hash_setline, /* doh_setline */
- Hash_getline, /* doh_getline */
- &HashHashMethods, /* doh_mapping */
- 0, /* doh_sequence */
- 0, /* doh_file */
- 0, /* doh_string */
- 0, /* doh_positional */
- 0,
- };
- /* -----------------------------------------------------------------------------
- * NewHash()
- *
- * Create a new hash table.
- * ----------------------------------------------------------------------------- */
- DOH *
- DohNewHash() {
- Hash *h;
- int i;
- h = (Hash *) DohMalloc(sizeof(Hash));
- h->hashsize = HASH_INIT_SIZE;
- h->hashtable = (HashNode **) DohMalloc(h->hashsize*sizeof(HashNode *));
- for (i = 0; i < h->hashsize; i++) {
- h->hashtable[i] = 0;
- }
- h->currentindex = -1;
- h->current = 0;
- h->nitems = 0;
- h->file = 0;
- h->line = 0;
- return DohObjMalloc(&DohHashType,h);
- }