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							1065 lines
						
					
					
						
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				| /**CFile*********************************************************************** | |
|  | |
|   FileName    [st.c] | |
|  | |
|   PackageName [st] | |
|  | |
|   Synopsis    [Symbol table package.] | |
|  | |
|   Description [The st library provides functions to create, maintain, | |
|   and query symbol tables.] | |
|  | |
|   SeeAlso     [] | |
|  | |
|   Author      [] | |
|  | |
|   Copyright   [] | |
|  | |
| ******************************************************************************/ | |
| 
 | |
| #include "util.h" | |
| #include "st.h" | |
|  | |
| /*---------------------------------------------------------------------------*/ | |
| /* Constant declarations                                                     */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Stucture declarations                                                     */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Type declarations                                                         */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Variable declarations                                                     */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| #ifndef lint | |
| static char rcsid[] UTIL_UNUSED = " $Id: st.c,v 1.12 2010/04/22 19:00:55 fabio Exp fabio $"; | |
| #endif | |
|  | |
| /*---------------------------------------------------------------------------*/ | |
| /* Macro declarations                                                        */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| #define ST_NUMCMP(x,y) ((x) != (y)) | |
|  | |
| #define ST_NUMHASH(x,size) ((unsigned long)(x)%(size)) | |
|  | |
| #if SIZEOF_VOID_P == 8 | |
| #define st_shift 3 | |
| #else | |
| #define st_shift 2 | |
| #endif | |
|  | |
| #define ST_PTRHASH(x,size) ((unsigned int)((unsigned long)(x)>>st_shift)%size) | |
|  | |
| #define EQUAL(func, x, y) \ | |
|     ((((func) == st_numcmp) || ((func) == st_ptrcmp)) ?\ | |
|       (ST_NUMCMP((x),(y)) == 0) : ((*func)((x), (y)) == 0)) | |
|  | |
| #define do_hash(key, table)\ | |
|     ((int)((table->hash == st_ptrhash) ? ST_PTRHASH((char *)(key),(table)->num_bins) :\ | |
|      (table->hash == st_numhash) ? ST_NUMHASH((char *)(key), (table)->num_bins) :\ | |
|      (*table->hash)((char *)(key), (table)->num_bins))) | |
|  | |
| #define PTR_NOT_EQUAL(table, ptr, user_key)\ | |
| (ptr != NIL(st_table_entry) && !EQUAL(table->compare, (char *)user_key, (ptr)->key)) | |
|  | |
| #define FIND_ENTRY(table, hash_val, key, ptr, last) \ | |
|     (last) = &(table)->bins[hash_val];\ | |
|     (ptr) = *(last);\ | |
|     while (PTR_NOT_EQUAL((table), (ptr), (key))) {\ | |
| 	(last) = &(ptr)->next; (ptr) = *(last);\ | |
|     }\ | |
|     if ((ptr) != NIL(st_table_entry) && (table)->reorder_flag) {\ | |
| 	*(last) = (ptr)->next;\ | |
| 	(ptr)->next = (table)->bins[hash_val];\ | |
| 	(table)->bins[hash_val] = (ptr);\ | |
|     } | |
|  | |
| /* This macro does not check if memory allocation fails. Use at you own risk */ | |
| #define ADD_DIRECT(table, key, value, hash_val, newt)\ | |
| {\ | |
|     if (table->num_entries/table->num_bins >= table->max_density) {\ | |
| 	rehash(table);\ | |
| 	hash_val = do_hash(key,table);\ | |
|     }\ | |
|     \ | |
|     newt = ALLOC(st_table_entry, 1);\ | |
|     \ | |
|     newt->key = (char *)key;\ | |
|     newt->record = value;\ | |
|     newt->next = table->bins[hash_val];\ | |
|     table->bins[hash_val] = newt;\ | |
|     table->num_entries++;\ | |
| } | |
|  | |
| /**AutomaticStart*************************************************************/ | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Static function prototypes                                                */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| static int rehash (st_table *); | |
| 
 | |
| /**AutomaticEnd***************************************************************/ | |
| 
 | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Definition of exported functions                                          */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Create and initialize a table.] | |
|  | |
|   Description [Create and initialize a table with the comparison function | |
|   compare_fn and hash function hash_fn. compare_fn is | |
|   <pre> | |
| 	int compare_fn(const char *key1, const char *key2) | |
|   </pre> | |
|   It returns <,=,> 0 depending on whether key1 <,=,> key2 by some measure.<p> | |
|   hash_fn is | |
|   <pre> | |
| 	int hash_fn(char *key, int modulus) | |
|   </pre> | |
|   It returns a integer between 0 and modulus-1 such that if | |
|   compare_fn(key1,key2) == 0 then hash_fn(key1) == hash_fn(key2).<p> | |
|   There are five predefined hash and comparison functions in st. | |
|   For keys as numbers: | |
|   <pre> | |
| 	 st_numhash(key, modulus) { return (unsigned int) key % modulus; } | |
|   </pre> | |
|   <pre> | |
| 	 st_numcmp(x,y) { return (int) x - (int) y; } | |
|   </pre> | |
|   For keys as pointers: | |
|   <pre> | |
| 	 st_ptrhash(key, modulus) { return ((unsigned int) key/4) % modulus } | |
|   </pre> | |
|   <pre> | |
| 	 st_ptrcmp(x,y) { return (int) x - (int) y; } | |
|   </pre> | |
|   For keys as strings: | |
|   <pre> | |
|          st_strhash(x,y) - a reasonable hashing function for strings | |
|   </pre> | |
|   <pre> | |
| 	 strcmp(x,y) - the standard library function | |
|   </pre> | |
|   It is recommended to use these particular functions if they fit your  | |
|   needs, since st will recognize certain of them and run more quickly | |
|   because of it.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table_with_params st_free_table] | |
|  | |
| ******************************************************************************/ | |
| st_table * | |
| st_init_table(ST_PFICPCP compare, ST_PFICPI hash) | |
| { | |
|     return st_init_table_with_params(compare, hash, ST_DEFAULT_INIT_TABLE_SIZE, | |
| 				     ST_DEFAULT_MAX_DENSITY, | |
| 				     ST_DEFAULT_GROW_FACTOR, | |
| 				     ST_DEFAULT_REORDER_FLAG); | |
| 
 | |
| } /* st_init_table */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Create a table with given parameters.] | |
|  | |
|   Description [The full blown table initializer.  compare and hash are | |
|   the same as in st_init_table. density is the largest the average | |
|   number of entries per hash bin there should be before the table is | |
|   grown.  grow_factor is the factor the table is grown by when it | |
|   becomes too full. size is the initial number of bins to be allocated | |
|   for the hash table.  If reorder_flag is non-zero, then every time an | |
|   entry is found, it is moved to the top of the chain.<p> | |
|   st_init_table(compare, hash) is equivelent to | |
|   <pre> | |
|   st_init_table_with_params(compare, hash, ST_DEFAULT_INIT_TABLE_SIZE, | |
| 			    ST_DEFAULT_MAX_DENSITY, | |
| 			    ST_DEFAULT_GROW_FACTOR, | |
| 			    ST_DEFAULT_REORDER_FLAG); | |
|   </pre> | |
|   ] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_free_table] | |
|  | |
| ******************************************************************************/ | |
| st_table * | |
| st_init_table_with_params( | |
|   ST_PFICPCP compare, | |
|   ST_PFICPI hash, | |
|   int size, | |
|   int density, | |
|   double grow_factor, | |
|   int reorder_flag) | |
| { | |
|     int i; | |
|     st_table *newt; | |
| 
 | |
|     newt = ALLOC(st_table, 1); | |
|     if (newt == NIL(st_table)) { | |
| 	return NIL(st_table); | |
|     } | |
|     newt->compare = compare; | |
|     newt->hash = hash; | |
|     newt->num_entries = 0; | |
|     newt->max_density = density; | |
|     newt->grow_factor = grow_factor; | |
|     newt->reorder_flag = reorder_flag; | |
|     if (size <= 0) { | |
| 	size = 1; | |
|     } | |
|     newt->num_bins = size; | |
|     newt->bins = ALLOC(st_table_entry *, size); | |
|     if (newt->bins == NIL(st_table_entry *)) { | |
| 	FREE(newt); | |
| 	return NIL(st_table); | |
|     } | |
|     for(i = 0; i < size; i++) { | |
| 	newt->bins[i] = 0; | |
|     } | |
|     return newt; | |
| 
 | |
| } /* st_init_table_with_params */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Free a table.] | |
|  | |
|   Description [Any internal storage associated with table is freed. | |
|   It is the user's responsibility to free any storage associated | |
|   with the pointers he placed in the table (by perhaps using | |
|   st_foreach).] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_init_table_with_params] | |
|  | |
| ******************************************************************************/ | |
| void | |
| st_free_table(st_table *table) | |
| { | |
|     st_table_entry *ptr, *next; | |
|     int i; | |
| 
 | |
|     for(i = 0; i < table->num_bins ; i++) { | |
| 	ptr = table->bins[i]; | |
| 	while (ptr != NIL(st_table_entry)) { | |
| 	    next = ptr->next; | |
| 	    FREE(ptr); | |
| 	    ptr = next; | |
| 	} | |
|     } | |
|     FREE(table->bins); | |
|     FREE(table); | |
| 
 | |
| } /* st_free_table */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Lookup up `key' in `table'.] | |
|  | |
|   Description [Lookup up `key' in `table'. If an entry is found, 1 is | |
|   returned and if `value' is not nil, the variable it points to is set | |
|   to the associated value.  If an entry is not found, 0 is returned | |
|   and the variable pointed by value is unchanged.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_lookup_int] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_lookup(st_table *table, void *key, void *value) | |
| { | |
|     int hash_val; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr, last); | |
| 
 | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	return 0; | |
|     } else { | |
| 	if (value != NIL(void)) { | |
| 	    *(char **)value = ptr->record; | |
| 	} | |
| 	return 1; | |
|     } | |
| 
 | |
| } /* st_lookup */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Lookup up `key' in `table'.] | |
|  | |
|   Description [Lookup up `key' in `table'.  If an entry is found, 1 is | |
|   returned and if `value' is not nil, the variable it points to is | |
|   set to the associated integer value.  If an entry is not found, 0 is | |
|   return and the variable pointed by `value' is unchanged.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_lookup] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_lookup_int(st_table *table, void *key, int *value) | |
| { | |
|     int hash_val; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr, last); | |
|      | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	return 0; | |
|     } else { | |
| 	if (value != NIL(int)) { | |
| 	    *value = (int) (long) ptr->record; | |
| 	} | |
| 	return 1; | |
|     } | |
| 
 | |
| } /* st_lookup_int */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Insert value in table under the key 'key'.] | |
|  | |
|   Description [Insert value in table under the key 'key'.  Returns 1 | |
|   if there was an entry already under the key; 0 if there was no entry | |
|   under the key and insertion was successful; ST_OUT_OF_MEM otherwise. | |
|   In either of the first two cases the new value is added.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_insert(st_table *table, void *key, void *value) | |
| { | |
|     int hash_val; | |
|     st_table_entry *newt; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr, last); | |
| 
 | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	if (table->num_entries/table->num_bins >= table->max_density) { | |
| 	    if (rehash(table) == ST_OUT_OF_MEM) { | |
| 		return ST_OUT_OF_MEM; | |
| 	    } | |
| 	    hash_val = do_hash(key, table); | |
| 	} | |
| 	newt = ALLOC(st_table_entry, 1); | |
| 	if (newt == NIL(st_table_entry)) { | |
| 	    return ST_OUT_OF_MEM; | |
| 	} | |
| 	newt->key = (char *)key; | |
| 	newt->record = (char *)value; | |
| 	newt->next = table->bins[hash_val]; | |
| 	table->bins[hash_val] = newt; | |
| 	table->num_entries++; | |
| 	return 0; | |
|     } else { | |
| 	ptr->record = (char *)value; | |
| 	return 1; | |
|     } | |
| 
 | |
| } /* st_insert */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Place 'value' in 'table' under the key 'key'.] | |
|  | |
|   Description [Place 'value' in 'table' under the key 'key'.  This is | |
|   done without checking if 'key' is in 'table' already.  This should | |
|   only be used if you are sure there is not already an entry for | |
|   'key', since it is undefined which entry you would later get from | |
|   st_lookup or st_find_or_add. Returns 1 if successful; ST_OUT_OF_MEM | |
|   otherwise.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_add_direct(st_table *table, void *key, void *value) | |
| { | |
|     int hash_val; | |
|     st_table_entry *newt; | |
|      | |
|     hash_val = do_hash(key, table); | |
|     if (table->num_entries / table->num_bins >= table->max_density) { | |
| 	if (rehash(table) == ST_OUT_OF_MEM) { | |
| 	    return ST_OUT_OF_MEM; | |
| 	} | |
|     } | |
|     hash_val = do_hash(key, table); | |
|     newt = ALLOC(st_table_entry, 1); | |
|     if (newt == NIL(st_table_entry)) { | |
| 	return ST_OUT_OF_MEM; | |
|     } | |
|     newt->key = (char *)key; | |
|     newt->record = (char *)value; | |
|     newt->next = table->bins[hash_val]; | |
|     table->bins[hash_val] = newt; | |
|     table->num_entries++; | |
|     return 1; | |
| 
 | |
| } /* st_add_direct */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Lookup `key' in `table'.] | |
|  | |
|   Description [Lookup `key' in `table'.  If not found, create an | |
|   entry.  In either case set slot to point to the field in the entry | |
|   where the value is stored.  The value associated with `key' may then | |
|   be changed by accessing directly through slot.  Returns 1 if an | |
|   entry already existed, 0 if it did not exist and creation was | |
|   successful; ST_OUT_OF_MEM otherwise.  As an example: | |
|   <pre> | |
|       char **slot; | |
|   </pre> | |
|   <pre> | |
|       char *key; | |
|   </pre> | |
|   <pre> | |
|       char *value = (char *) item_ptr <-- ptr to a malloc'd structure | |
|   </pre> | |
|   <pre> | |
|       if (st_find_or_add(table, key, &slot) == 1) { | |
|   </pre> | |
|   <pre> | |
| 	 FREE(*slot); <-- free the old value of the record | |
|   </pre> | |
|   <pre> | |
|       } | |
|   </pre> | |
|   <pre> | |
|       *slot = value;  <-- attach the new value to the record | |
|   </pre> | |
|   This replaces the equivelent code: | |
|   <pre> | |
|       if (st_lookup(table, key, &ovalue) == 1) { | |
|   </pre> | |
|   <pre> | |
|          FREE(ovalue); | |
|   </pre> | |
|   <pre> | |
|       } | |
|   </pre> | |
|   <pre> | |
|       st_insert(table, key, value); | |
|   </pre> | |
|   ] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_find] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_find_or_add(st_table *table, void *key, void *slot) | |
| { | |
|     int hash_val; | |
|     st_table_entry *newt, *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr, last); | |
| 
 | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	if (table->num_entries / table->num_bins >= table->max_density) { | |
| 	    if (rehash(table) == ST_OUT_OF_MEM) { | |
| 		return ST_OUT_OF_MEM; | |
| 	    } | |
| 	    hash_val = do_hash(key, table); | |
| 	} | |
| 	newt = ALLOC(st_table_entry, 1); | |
| 	if (newt == NIL(st_table_entry)) { | |
| 	    return ST_OUT_OF_MEM; | |
| 	} | |
| 	newt->key = (char *)key; | |
| 	newt->record = (char *) 0; | |
| 	newt->next = table->bins[hash_val]; | |
| 	table->bins[hash_val] = newt; | |
| 	table->num_entries++; | |
| 	if (slot != NIL(void)) *(char ***)slot = &newt->record; | |
| 	return 0; | |
|     } else { | |
| 	if (slot != NIL(void)) *(char ***)slot = &ptr->record; | |
| 	return 1; | |
|     } | |
| 
 | |
| } /* st_find_or_add */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Lookup `key' in `table'.] | |
|  | |
|   Description [Like st_find_or_add, but does not create an entry if | |
|   one is not found.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_find_or_add] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_find(st_table *table, void *key, void *slot) | |
| { | |
|     int hash_val; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr, last); | |
| 
 | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	return 0; | |
|     } else { | |
| 	if (slot != NIL(void)) { | |
| 	    *(char ***)slot = &ptr->record; | |
| 	} | |
| 	return 1; | |
|     } | |
| 
 | |
| } /* st_find */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Return a copy of old_table and all its members.] | |
|  | |
|   Description [Return a copy of old_table and all its members. | |
|   (st_table *) 0 is returned if there was insufficient memory to do | |
|   the copy.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [] | |
|  | |
| ******************************************************************************/ | |
| st_table * | |
| st_copy(st_table *old_table) | |
| { | |
|     st_table *new_table; | |
|     st_table_entry *ptr, *newptr, *next, *newt; | |
|     int i, j, num_bins = old_table->num_bins; | |
| 
 | |
|     new_table = ALLOC(st_table, 1); | |
|     if (new_table == NIL(st_table)) { | |
| 	return NIL(st_table); | |
|     } | |
|      | |
|     *new_table = *old_table; | |
|     new_table->bins = ALLOC(st_table_entry *, num_bins); | |
|     if (new_table->bins == NIL(st_table_entry *)) { | |
| 	FREE(new_table); | |
| 	return NIL(st_table); | |
|     } | |
|     for(i = 0; i < num_bins ; i++) { | |
| 	new_table->bins[i] = NIL(st_table_entry); | |
| 	ptr = old_table->bins[i]; | |
| 	while (ptr != NIL(st_table_entry)) { | |
| 	    newt = ALLOC(st_table_entry, 1); | |
| 	    if (newt == NIL(st_table_entry)) { | |
| 		for (j = 0; j <= i; j++) { | |
| 		    newptr = new_table->bins[j]; | |
| 		    while (newptr != NIL(st_table_entry)) { | |
| 			next = newptr->next; | |
| 			FREE(newptr); | |
| 			newptr = next; | |
| 		    } | |
| 		} | |
| 		FREE(new_table->bins); | |
| 		FREE(new_table); | |
| 		return NIL(st_table); | |
| 	    } | |
| 	    *newt = *ptr; | |
| 	    newt->next = new_table->bins[i]; | |
| 	    new_table->bins[i] = newt; | |
| 	    ptr = ptr->next; | |
| 	} | |
|     } | |
|     return new_table; | |
| 
 | |
| } /* st_copy */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Delete the entry with the key pointed to by `keyp'.] | |
|  | |
|   Description [Delete the entry with the key pointed to by `keyp'.  If | |
|   the entry is found, 1 is returned, the variable pointed by `keyp' is | |
|   set to the actual key and the variable pointed by `value' is set to | |
|   the corresponding entry.  (This allows the freeing of the associated | |
|   storage.)  If the entry is not found, then 0 is returned and nothing | |
|   is changed.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_delete_int] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_delete(st_table *table, void *keyp, void *value) | |
| { | |
|     int hash_val; | |
|     char *key = *(char **)keyp; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr ,last); | |
|      | |
|     if (ptr == NIL(st_table_entry)) { | |
| 	return 0; | |
|     } | |
| 
 | |
|     *last = ptr->next; | |
|     if (value != NIL(void)) *(char **)value = ptr->record; | |
|     *(char **)keyp = ptr->key; | |
|     FREE(ptr); | |
|     table->num_entries--; | |
|     return 1; | |
| 
 | |
| } /* st_delete */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Delete the entry with the key pointed to by `keyp'.] | |
|  | |
|   Description [Delete the entry with the key pointed to by `keyp'. | |
|   `value' must be a pointer to an integer.  If the entry is found, 1 | |
|   is returned, the variable pointed by `keyp' is set to the actual key | |
|   and the variable pointed by `value' is set to the corresponding | |
|   entry.  (This allows the freeing of the associated storage.) If the | |
|   entry is not found, then 0 is returned and nothing is changed.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_delete] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_delete_int(st_table *table, void *keyp, int *value) | |
| { | |
|     int hash_val; | |
|     char *key = *(char **)keyp; | |
|     st_table_entry *ptr, **last; | |
| 
 | |
|     hash_val = do_hash(key, table); | |
| 
 | |
|     FIND_ENTRY(table, hash_val, key, ptr ,last); | |
| 
 | |
|     if (ptr == NIL(st_table_entry)) { | |
|         return 0; | |
|     } | |
| 
 | |
|     *last = ptr->next; | |
|     if (value != NIL(int)) *value = (int) (long) ptr->record; | |
|     *(char **)keyp = ptr->key; | |
|     FREE(ptr); | |
|     table->num_entries--; | |
|     return 1; | |
| 
 | |
| } /* st_delete_int */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Iterates over the elements of a table.] | |
|  | |
|   Description [For each (key, value) record in `table', st_foreach | |
|   call func with the arguments | |
|   <pre> | |
| 	  (*func)(key, value, arg) | |
|   </pre> | |
|   If func returns ST_CONTINUE, st_foreach continues processing | |
|   entries.  If func returns ST_STOP, st_foreach stops processing and | |
|   returns immediately. If func returns ST_DELETE, then the entry is | |
|   deleted from the symbol table and st_foreach continues.  In the case | |
|   of ST_DELETE, it is func's responsibility to free the key and value, | |
|   if necessary.<p> | |
|  | |
|   The routine returns 1 if all items in the table were generated and 0 | |
|   if the generation sequence was aborted using ST_STOP.  The order in | |
|   which the records are visited will be seemingly random.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_foreach_item st_foreach_item_int] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_foreach(st_table *table, ST_PFSR func, char *arg) | |
| { | |
|     st_table_entry *ptr, **last; | |
|     enum st_retval retval; | |
|     int i; | |
| 
 | |
|     for(i = 0; i < table->num_bins; i++) { | |
| 	last = &table->bins[i]; ptr = *last; | |
| 	while (ptr != NIL(st_table_entry)) { | |
| 	    retval = (*func)(ptr->key, ptr->record, arg); | |
| 	    switch (retval) { | |
| 	    case ST_CONTINUE: | |
| 		last = &ptr->next; ptr = *last; | |
| 		break; | |
| 	    case ST_STOP: | |
| 		return 0; | |
| 	    case ST_DELETE: | |
| 		*last = ptr->next; | |
| 		table->num_entries--;	/* cstevens@ic */ | |
| 		FREE(ptr); | |
| 		ptr = *last; | |
| 	    } | |
| 	} | |
|     } | |
|     return 1; | |
| 
 | |
| } /* st_foreach */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [String hash function.] | |
|  | |
|   Description [String hash function.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_strhash(char *string, int modulus) | |
| { | |
|     int val = 0; | |
|     int c; | |
|      | |
|     while ((c = *string++) != '\0') { | |
| 	val = val*997 + c; | |
|     } | |
| 
 | |
|     return ((val < 0) ? -val : val)%modulus; | |
| 
 | |
| } /* st_strhash */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Number hash function.] | |
|  | |
|   Description [Integer number hash function.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_numcmp] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_numhash(char *x, int size) | |
| { | |
|     return ST_NUMHASH(x, size); | |
| 
 | |
| } /* st_numhash */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Pointer hash function.] | |
|  | |
|   Description [Pointer hash function.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_ptrcmp] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_ptrhash(char *x, int size) | |
| { | |
|     return ST_PTRHASH(x, size); | |
| 
 | |
| } /* st_ptrhash */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Number comparison function.] | |
|  | |
|   Description [integer number comparison function.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_numhash] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_numcmp(const char *x, const char *y) | |
| { | |
|     return ST_NUMCMP(x, y); | |
| 
 | |
| } /* st_numcmp */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Pointer comparison function.] | |
|  | |
|   Description [Pointer comparison function.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_table st_ptrhash] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_ptrcmp(const char *x, const char *y) | |
| { | |
|     return ST_NUMCMP(x, y); | |
| 
 | |
| } /* st_ptrcmp */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Initializes a generator.] | |
|  | |
|   Description [Returns a generator handle which when used with | |
|   st_gen() will progressively return each (key, value) record in | |
|   `table'.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_free_gen] | |
|  | |
| ******************************************************************************/ | |
| st_generator * | |
| st_init_gen(st_table *table) | |
| { | |
|     st_generator *gen; | |
| 
 | |
|     gen = ALLOC(st_generator, 1); | |
|     if (gen == NIL(st_generator)) { | |
| 	return NIL(st_generator); | |
|     } | |
|     gen->table = table; | |
|     gen->entry = NIL(st_table_entry); | |
|     gen->index = 0; | |
|     return gen; | |
| 
 | |
| } /* st_init_gen */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis [returns the next (key, value) pair in the generation | |
|   sequence. ] | |
|  | |
|   Description [Given a generator returned by st_init_gen(), this | |
|   routine returns the next (key, value) pair in the generation | |
|   sequence.  The pointer `value_p' can be zero which means no value | |
|   will be returned.  When there are no more items in the generation | |
|   sequence, the routine returns 0. | |
|  | |
|   While using a generation sequence, deleting any (key, value) pair | |
|   other than the one just generated may cause a fatal error when | |
|   st_gen() is called later in the sequence and is therefore not | |
|   recommended.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_gen_int] | |
|  | |
| ******************************************************************************/ | |
| int | |
| st_gen(st_generator *gen, void *key_p, void *value_p) | |
| { | |
|     int i; | |
| 
 | |
|     if (gen->entry == NIL(st_table_entry)) { | |
| 	/* try to find next entry */ | |
| 	for(i = gen->index; i < gen->table->num_bins; i++) { | |
| 	    if (gen->table->bins[i] != NIL(st_table_entry)) { | |
| 		gen->index = i+1; | |
| 		gen->entry = gen->table->bins[i]; | |
| 		break; | |
| 	    } | |
| 	} | |
| 	if (gen->entry == NIL(st_table_entry)) { | |
| 	    return 0;		/* that's all folks ! */ | |
| 	} | |
|     } | |
|     *(char **)key_p = gen->entry->key; | |
|     if (value_p != NIL(void)) { | |
| 	*(char **)value_p = gen->entry->record; | |
|     } | |
|     gen->entry = gen->entry->next; | |
|     return 1; | |
| 
 | |
| } /* st_gen */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Returns the next (key, value) pair in the generation | |
|   sequence.] | |
|  | |
|   Description [Given a generator returned by st_init_gen(), this | |
|   routine returns the next (key, value) pair in the generation | |
|   sequence.  `value_p' must be a pointer to an integer.  The pointer | |
|   `value_p' can be zero which means no value will be returned.  When | |
|   there are no more items in the generation sequence, the routine | |
|   returns 0.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_gen] | |
|  | |
| ******************************************************************************/ | |
| int  | |
| st_gen_int(st_generator *gen, void *key_p, int *value_p) | |
| { | |
|     int i; | |
| 
 | |
|     if (gen->entry == NIL(st_table_entry)) { | |
| 	/* try to find next entry */ | |
| 	for(i = gen->index; i < gen->table->num_bins; i++) { | |
| 	    if (gen->table->bins[i] != NIL(st_table_entry)) { | |
| 		gen->index = i+1; | |
| 		gen->entry = gen->table->bins[i]; | |
| 		break; | |
| 	    } | |
| 	} | |
| 	if (gen->entry == NIL(st_table_entry)) { | |
| 	    return 0;		/* that's all folks ! */ | |
| 	} | |
|     } | |
|     *(char **)key_p = gen->entry->key; | |
|     if (value_p != NIL(int)) { | |
|    	*value_p = (int) (long) gen->entry->record; | |
|     } | |
|     gen->entry = gen->entry->next; | |
|     return 1; | |
| 
 | |
| } /* st_gen_int */ | |
| 
 | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Reclaims the resources associated with `gen'.] | |
|  | |
|   Description [After generating all items in a generation sequence, | |
|   this routine must be called to reclaim the resources associated with | |
|   `gen'.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_init_gen] | |
|  | |
| ******************************************************************************/ | |
| void | |
| st_free_gen(st_generator *gen) | |
| { | |
|     FREE(gen); | |
| 
 | |
| } /* st_free_gen */ | |
| 
 | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Definition of internal functions                                          */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /*---------------------------------------------------------------------------*/ | |
| /* Definition of static functions                                            */ | |
| /*---------------------------------------------------------------------------*/ | |
| 
 | |
| /**Function******************************************************************** | |
|  | |
|   Synopsis    [Rehashes a symbol table.] | |
|  | |
|   Description [Rehashes a symbol table.] | |
|  | |
|   SideEffects [None] | |
|  | |
|   SeeAlso     [st_insert] | |
|  | |
| ******************************************************************************/ | |
| static int | |
| rehash(st_table *table) | |
| { | |
|     st_table_entry *ptr, *next, **old_bins; | |
|     int             i, old_num_bins, hash_val, old_num_entries; | |
| 
 | |
|     /* save old values */ | |
|     old_bins = table->bins; | |
|     old_num_bins = table->num_bins; | |
|     old_num_entries = table->num_entries; | |
| 
 | |
|     /* rehash */ | |
|     table->num_bins = (int) (table->grow_factor * old_num_bins); | |
|     if (table->num_bins % 2 == 0) { | |
| 	table->num_bins += 1; | |
|     } | |
|     table->num_entries = 0; | |
|     table->bins = ALLOC(st_table_entry *, table->num_bins); | |
|     if (table->bins == NIL(st_table_entry *)) { | |
| 	table->bins = old_bins; | |
| 	table->num_bins = old_num_bins; | |
| 	table->num_entries = old_num_entries; | |
| 	return ST_OUT_OF_MEM; | |
|     } | |
|     /* initialize */ | |
|     for (i = 0; i < table->num_bins; i++) { | |
| 	table->bins[i] = 0; | |
|     } | |
| 
 | |
|     /* copy data over */ | |
|     for (i = 0; i < old_num_bins; i++) { | |
| 	ptr = old_bins[i]; | |
| 	while (ptr != NIL(st_table_entry)) { | |
| 	    next = ptr->next; | |
| 	    hash_val = do_hash(ptr->key, table); | |
| 	    ptr->next = table->bins[hash_val]; | |
| 	    table->bins[hash_val] = ptr; | |
| 	    table->num_entries++; | |
| 	    ptr = next; | |
| 	} | |
|     } | |
|     FREE(old_bins); | |
| 
 | |
|     return 1; | |
| 
 | |
| } /* rehash */
 |