/* -*-c-*-
*
- * $Id: sym.c,v 1.10 1999/12/10 23:42:04 mdw Exp $
+ * $Id: sym.c,v 1.15 2004/04/08 01:36:13 mdw Exp $
*
* Symbol table management
*
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: sym.c,v $
- * Revision 1.10 1999/12/10 23:42:04 mdw
- * Change header file guard names.
- *
- * Revision 1.9 1999/10/22 22:36:37 mdw
- * New test structure for symbol tables.
- *
- * Revision 1.8 1999/08/02 14:45:48 mdw
- * Break low-level hashtable code out from sym.
- *
- * Revision 1.7 1999/06/01 09:49:08 mdw
- * Allow things to be looked up by just their caller-supplied hashes. This
- * actually needs to be thought through better.
- *
- * Revision 1.6 1999/05/26 21:08:31 mdw
- * Rename symbols in line with newer conventions.
- *
- * Revision 1.5 1999/05/13 22:48:37 mdw
- * Twiddle the extension threshold. Change `-ise' to `-ize' throughout.
- *
- * Revision 1.4 1999/05/06 19:51:35 mdw
- * Reformatted the LGPL notice a little bit.
- *
- * Revision 1.3 1999/05/05 18:50:31 mdw
- * Change licensing conditions to LGPL.
- *
- * Revision 1.2 1998/11/26 19:27:33 mdw
- * Move SYM_NAME into the header file. Fix bugs.
- *
- * Revision 1.1.1.1 1998/06/17 23:44:42 mdw
- * Initial version of mLib
- *
- */
-
/*----- Header files ------------------------------------------------------*/
/* --- ANSI headers --- */
/* --- Local headers --- */
#include "alloc.h"
+#include "arena.h"
#include "bits.h"
-#include "crc32.h"
#include "exc.h"
#include "hash.h"
#include "sub.h"
#include "sym.h"
-#include "track.h"
-
-/*----- Tuning parameters -------------------------------------------------*/
-
-/* --- Initial hash table size --- *
- *
- * This is the initial @mask@ value. It must be of the form %$2^n - 1$%,
- * so that it can be used to mask of the bottom bits of a hash value.
- */
-
-#define SYM_INITSZ 64 /* Size of a new hash table */
-
-/* --- Maximum load factor --- *
- *
- * This parameter controls how much the table has to be loaded before the
- * table is extended. The number of elements %$n$%, the number of bins %$b$%
- * and the limit %$l$% satisfy the relation %$n < bl$%; if a new item is
- * added to the table and this relation is found to be false, the table is
- * doubled in size.
- */
-
-#define SYM_LIMIT(n) ((n) * 2) /* Load factor for growing table */
+#include "unihash.h"
/*----- Main code ---------------------------------------------------------*/
void sym_create(sym_table *t)
{
- TRACK_CTX("symbol table creation");
- TRACK_PUSH;
hash_create(&t->t, SYM_INITSZ);
+ t->s = &sub_global;
t->load = SYM_LIMIT(SYM_INITSZ);
- TRACK_POP;
}
/* --- @sym_destroy@ --- *
{
sym_iter i;
- TRACK_CTX("symbol table destruction");
- TRACK_PUSH;
-
SYM_MKITER(&i, t);
for (;;) {
sym_base *p;
SYM_NEXT(&i, p);
if (!p)
break;
- if (p->len > SYM_BUFSZ)
- sub_free(p->name.p, p->len);
- free(p);
+ x_free(t->t.a, p);
}
hash_destroy(&t->t);
-
- TRACK_POP;
}
/* --- @sym_find@ --- *
*
* Arguments: @sym_table *t@ = pointer to symbol table in question
- * @const char *n@ = pointer to symbol table to look up
+ * @const char *n@ = pointer to symbol name to look up
* @long l@ = length of the name string or negative to measure
* @size_t sz@ = size of desired symbol object, or zero
* @unsigned *f@ = pointer to a flag, or null.
/* --- Find the correct bin --- */
- len = l < 0 ? strlen(n) + 1 : l;
- CRC32(hash, 0, n, len);
+ len = l < 0 ? strlen(n) : l;
+ hash = UNIHASH(&unihash_global, n, len);
bin = HASH_BIN(&t->t, hash);
/* --- Search the bin list --- */
if (f) *f = 0;
if (!sz) return (0);
- /* --- Create a new symbol block and initialize it --- */
-
- {
- TRACK_CTX("new symbol creation");
- TRACK_PUSH;
-
- q = xmalloc(sz);
- q->b.next = *bin;
- q->b.hash = hash;
- q->len = len;
- if (n) {
- if (len <= SYM_BUFSZ)
- memcpy(q->name.b, n, len);
- else {
- TRY {
- q->name.p = sub_alloc(len);
- memcpy(q->name.p, n, len);
- } CATCH {
- free(q);
- TRACK_POP;
- RETHROW;
- } END_TRY;
- }
- }
-
- TRACK_POP;
- }
-
+ /* --- Create a new symbol block and initialize it --- *
+ *
+ * The name is attached to the end of the symbol block.
+ */
+
+ q = x_alloc(t->t.a, sz + len + 1);
+ q->b.next = *bin;
+ q->b.hash = hash;
+ q->name = (char *)q + sz;
+ memcpy(q->name, n, len);
+ q->name[len] = 0;
+ q->len = len;
*bin = &q->b;
/* --- Consider growing the array --- */
if (t->load)
t->load--;
if (!t->load && hash_extend(&t->t))
- t->load = SYM_LIMIT(t->t.mask / 2 + 1);
+ t->load = SYM_LIMIT(t->t.mask + 1);
/* --- Finished that, so return the new symbol block --- */
{
sym_base *q = p;
hash_remove(&t->t, &q->b);
- if (q->len > SYM_BUFSZ)
- sub_free(q->name.p, q->len);
- free(q);
+ xfree(q);
t->load++;
}
~mdw / mLib / blobdiff