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-rw-r--r--src/st.c578
1 files changed, 578 insertions, 0 deletions
diff --git a/src/st.c b/src/st.c
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index 0000000..022880a
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+++ b/src/st.c
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+/* This is a public domain general purpose hash table package written by Peter Moore @ UCB. */
+
+/* static char sccsid[] = "@(#) st.c 5.1 89/12/14 Crucible"; */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef _WIN32
+#include <malloc.h>
+#endif
+
+#include "regint.h"
+#include "st.h"
+
+typedef struct st_table_entry st_table_entry;
+
+struct st_table_entry {
+ unsigned int hash;
+ st_data_t key;
+ st_data_t record;
+ st_table_entry *next;
+};
+
+#define ST_DEFAULT_MAX_DENSITY 5
+#define ST_DEFAULT_INIT_TABLE_SIZE 11
+
+ /*
+ * DEFAULT_MAX_DENSITY is the default for the largest we allow the
+ * average number of items per bin before increasing the number of
+ * bins
+ *
+ * DEFAULT_INIT_TABLE_SIZE is the default for the number of bins
+ * allocated initially
+ *
+ */
+
+static int numcmp(long, long);
+static int numhash(long);
+static struct st_hash_type type_numhash = {
+ numcmp,
+ numhash,
+};
+
+/* extern int strcmp(const char *, const char *); */
+static int strhash(const char *);
+static struct st_hash_type type_strhash = {
+ strcmp,
+ strhash,
+};
+
+static void rehash(st_table *);
+
+#define alloc(type) (type*)xmalloc((unsigned)sizeof(type))
+#define Calloc(n,s) (char*)xcalloc((n),(s))
+
+#define EQUAL(table,x,y) ((x)==(y) || (*table->type->compare)((x),(y)) == 0)
+
+#define do_hash(key,table) (unsigned int)(*(table)->type->hash)((key))
+#define do_hash_bin(key,table) (do_hash(key, table)%(table)->num_bins)
+
+/*
+ * MINSIZE is the minimum size of a dictionary.
+ */
+
+#define MINSIZE 8
+
+/*
+Table of prime numbers 2^n+a, 2<=n<=30.
+*/
+static const long primes[] = {
+ 8 + 3,
+ 16 + 3,
+ 32 + 5,
+ 64 + 3,
+ 128 + 3,
+ 256 + 27,
+ 512 + 9,
+ 1024 + 9,
+ 2048 + 5,
+ 4096 + 3,
+ 8192 + 27,
+ 16384 + 43,
+ 32768 + 3,
+ 65536 + 45,
+ 131072 + 29,
+ 262144 + 3,
+ 524288 + 21,
+ 1048576 + 7,
+ 2097152 + 17,
+ 4194304 + 15,
+ 8388608 + 9,
+ 16777216 + 43,
+ 33554432 + 35,
+ 67108864 + 15,
+ 134217728 + 29,
+ 268435456 + 3,
+ 536870912 + 11,
+ 1073741824 + 85,
+ 0
+};
+
+static int
+new_size(size)
+ int size;
+{
+ int i;
+
+#if 0
+ for (i=3; i<31; i++) {
+ if ((1<<i) > size) return 1<<i;
+ }
+ return -1;
+#else
+ int newsize;
+
+ for (i = 0, newsize = MINSIZE;
+ i < (int )(sizeof(primes)/sizeof(primes[0]));
+ i++, newsize <<= 1)
+ {
+ if (newsize > size) return primes[i];
+ }
+ /* Ran out of polynomials */
+ return -1; /* should raise exception */
+#endif
+}
+
+#ifdef HASH_LOG
+static int collision = 0;
+static int init_st = 0;
+
+static void
+stat_col()
+{
+ FILE *f = fopen("/tmp/col", "w");
+ fprintf(f, "collision: %d\n", collision);
+ fclose(f);
+}
+#endif
+
+st_table*
+st_init_table_with_size(type, size)
+ struct st_hash_type *type;
+ int size;
+{
+ st_table *tbl;
+
+#ifdef HASH_LOG
+ if (init_st == 0) {
+ init_st = 1;
+ atexit(stat_col);
+ }
+#endif
+
+ size = new_size(size); /* round up to prime number */
+
+ tbl = alloc(st_table);
+ tbl->type = type;
+ tbl->num_entries = 0;
+ tbl->num_bins = size;
+ tbl->bins = (st_table_entry **)Calloc(size, sizeof(st_table_entry*));
+
+ return tbl;
+}
+
+st_table*
+st_init_table(type)
+ struct st_hash_type *type;
+{
+ return st_init_table_with_size(type, 0);
+}
+
+st_table*
+st_init_numtable(void)
+{
+ return st_init_table(&type_numhash);
+}
+
+st_table*
+st_init_numtable_with_size(size)
+ int size;
+{
+ return st_init_table_with_size(&type_numhash, size);
+}
+
+st_table*
+st_init_strtable(void)
+{
+ return st_init_table(&type_strhash);
+}
+
+st_table*
+st_init_strtable_with_size(size)
+ int size;
+{
+ return st_init_table_with_size(&type_strhash, size);
+}
+
+void
+st_free_table(table)
+ st_table *table;
+{
+ register st_table_entry *ptr, *next;
+ int i;
+
+ for(i = 0; i < table->num_bins; i++) {
+ ptr = table->bins[i];
+ while (ptr != 0) {
+ next = ptr->next;
+ free(ptr);
+ ptr = next;
+ }
+ }
+ free(table->bins);
+ free(table);
+}
+
+#define PTR_NOT_EQUAL(table, ptr, hash_val, key) \
+((ptr) != 0 && (ptr->hash != (hash_val) || !EQUAL((table), (key), (ptr)->key)))
+
+#ifdef HASH_LOG
+#define COLLISION collision++
+#else
+#define COLLISION
+#endif
+
+#define FIND_ENTRY(table, ptr, hash_val, bin_pos) do {\
+ bin_pos = hash_val%(table)->num_bins;\
+ ptr = (table)->bins[bin_pos];\
+ if (PTR_NOT_EQUAL(table, ptr, hash_val, key)) {\
+ COLLISION;\
+ while (PTR_NOT_EQUAL(table, ptr->next, hash_val, key)) {\
+ ptr = ptr->next;\
+ }\
+ ptr = ptr->next;\
+ }\
+} while (0)
+
+int
+st_lookup(table, key, value)
+ st_table *table;
+ register st_data_t key;
+ st_data_t *value;
+{
+ unsigned int hash_val, bin_pos;
+ register st_table_entry *ptr;
+
+ hash_val = do_hash(key, table);
+ FIND_ENTRY(table, ptr, hash_val, bin_pos);
+
+ if (ptr == 0) {
+ return 0;
+ }
+ else {
+ if (value != 0) *value = ptr->record;
+ return 1;
+ }
+}
+
+#define ADD_DIRECT(table, key, value, hash_val, bin_pos)\
+do {\
+ st_table_entry *entry;\
+ if (table->num_entries/(table->num_bins) > ST_DEFAULT_MAX_DENSITY) {\
+ rehash(table);\
+ bin_pos = hash_val % table->num_bins;\
+ }\
+ \
+ entry = alloc(st_table_entry);\
+ \
+ entry->hash = hash_val;\
+ entry->key = key;\
+ entry->record = value;\
+ entry->next = table->bins[bin_pos];\
+ table->bins[bin_pos] = entry;\
+ table->num_entries++;\
+} while (0)
+
+int
+st_insert(table, key, value)
+ register st_table *table;
+ register st_data_t key;
+ st_data_t value;
+{
+ unsigned int hash_val, bin_pos;
+ register st_table_entry *ptr;
+
+ hash_val = do_hash(key, table);
+ FIND_ENTRY(table, ptr, hash_val, bin_pos);
+
+ if (ptr == 0) {
+ ADD_DIRECT(table, key, value, hash_val, bin_pos);
+ return 0;
+ }
+ else {
+ ptr->record = value;
+ return 1;
+ }
+}
+
+void
+st_add_direct(table, key, value)
+ st_table *table;
+ st_data_t key;
+ st_data_t value;
+{
+ unsigned int hash_val, bin_pos;
+
+ hash_val = do_hash(key, table);
+ bin_pos = hash_val % table->num_bins;
+ ADD_DIRECT(table, key, value, hash_val, bin_pos);
+}
+
+static void
+rehash(table)
+ register st_table *table;
+{
+ register st_table_entry *ptr, *next, **new_bins;
+ int i, old_num_bins = table->num_bins, new_num_bins;
+ unsigned int hash_val;
+
+ new_num_bins = new_size(old_num_bins+1);
+ new_bins = (st_table_entry**)Calloc(new_num_bins, sizeof(st_table_entry*));
+
+ for(i = 0; i < old_num_bins; i++) {
+ ptr = table->bins[i];
+ while (ptr != 0) {
+ next = ptr->next;
+ hash_val = ptr->hash % new_num_bins;
+ ptr->next = new_bins[hash_val];
+ new_bins[hash_val] = ptr;
+ ptr = next;
+ }
+ }
+ free(table->bins);
+ table->num_bins = new_num_bins;
+ table->bins = new_bins;
+}
+
+st_table*
+st_copy(old_table)
+ st_table *old_table;
+{
+ st_table *new_table;
+ st_table_entry *ptr, *entry;
+ int i, num_bins = old_table->num_bins;
+
+ new_table = alloc(st_table);
+ if (new_table == 0) {
+ return 0;
+ }
+
+ *new_table = *old_table;
+ new_table->bins = (st_table_entry**)
+ Calloc((unsigned)num_bins, sizeof(st_table_entry*));
+
+ if (new_table->bins == 0) {
+ free(new_table);
+ return 0;
+ }
+
+ for(i = 0; i < num_bins; i++) {
+ new_table->bins[i] = 0;
+ ptr = old_table->bins[i];
+ while (ptr != 0) {
+ entry = alloc(st_table_entry);
+ if (entry == 0) {
+ free(new_table->bins);
+ free(new_table);
+ return 0;
+ }
+ *entry = *ptr;
+ entry->next = new_table->bins[i];
+ new_table->bins[i] = entry;
+ ptr = ptr->next;
+ }
+ }
+ return new_table;
+}
+
+int
+st_delete(table, key, value)
+ register st_table *table;
+ register st_data_t *key;
+ st_data_t *value;
+{
+ unsigned int hash_val;
+ st_table_entry *tmp;
+ register st_table_entry *ptr;
+
+ hash_val = do_hash_bin(*key, table);
+ ptr = table->bins[hash_val];
+
+ if (ptr == 0) {
+ if (value != 0) *value = 0;
+ return 0;
+ }
+
+ if (EQUAL(table, *key, ptr->key)) {
+ table->bins[hash_val] = ptr->next;
+ table->num_entries--;
+ if (value != 0) *value = ptr->record;
+ *key = ptr->key;
+ free(ptr);
+ return 1;
+ }
+
+ for(; ptr->next != 0; ptr = ptr->next) {
+ if (EQUAL(table, ptr->next->key, *key)) {
+ tmp = ptr->next;
+ ptr->next = ptr->next->next;
+ table->num_entries--;
+ if (value != 0) *value = tmp->record;
+ *key = tmp->key;
+ free(tmp);
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+int
+st_delete_safe(table, key, value, never)
+ register st_table *table;
+ register st_data_t *key;
+ st_data_t *value;
+ st_data_t never;
+{
+ unsigned int hash_val;
+ register st_table_entry *ptr;
+
+ hash_val = do_hash_bin(*key, table);
+ ptr = table->bins[hash_val];
+
+ if (ptr == 0) {
+ if (value != 0) *value = 0;
+ return 0;
+ }
+
+ for(; ptr != 0; ptr = ptr->next) {
+ if ((ptr->key != never) && EQUAL(table, ptr->key, *key)) {
+ table->num_entries--;
+ *key = ptr->key;
+ if (value != 0) *value = ptr->record;
+ ptr->key = ptr->record = never;
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int
+#if defined(__GNUC__)
+delete_never(st_data_t key __attribute__ ((unused)), st_data_t value,
+ st_data_t never)
+#else
+delete_never(key, value, never)
+ st_data_t key, value, never;
+#endif
+{
+ if (value == never) return ST_DELETE;
+ return ST_CONTINUE;
+}
+
+void
+st_cleanup_safe(table, never)
+ st_table *table;
+ st_data_t never;
+{
+ int num_entries = table->num_entries;
+
+ st_foreach(table, delete_never, never);
+ table->num_entries = num_entries;
+}
+
+int
+st_foreach(table, func, arg)
+ st_table *table;
+ int (*func)();
+ st_data_t arg;
+{
+ st_table_entry *ptr, *last, *tmp;
+ enum st_retval retval;
+ int i;
+
+ for(i = 0; i < table->num_bins; i++) {
+ last = 0;
+ for(ptr = table->bins[i]; ptr != 0;) {
+ retval = (*func)(ptr->key, ptr->record, arg);
+ switch (retval) {
+ case ST_CHECK: /* check if hash is modified during iteration */
+ tmp = 0;
+ if (i < table->num_bins) {
+ for (tmp = table->bins[i]; tmp; tmp=tmp->next) {
+ if (tmp == ptr) break;
+ }
+ }
+ if (!tmp) {
+ /* call func with error notice */
+ return 1;
+ }
+ /* fall through */
+ case ST_CONTINUE:
+ last = ptr;
+ ptr = ptr->next;
+ break;
+ case ST_STOP:
+ return 0;
+ case ST_DELETE:
+ tmp = ptr;
+ if (last == 0) {
+ table->bins[i] = ptr->next;
+ }
+ else {
+ last->next = ptr->next;
+ }
+ ptr = ptr->next;
+ free(tmp);
+ table->num_entries--;
+ }
+ }
+ }
+ return 0;
+}
+
+static int
+strhash(string)
+ register const char *string;
+{
+ register int c;
+
+#ifdef HASH_ELFHASH
+ register unsigned int h = 0, g;
+
+ while ((c = *string++) != '\0') {
+ h = ( h << 4 ) + c;
+ if ( g = h & 0xF0000000 )
+ h ^= g >> 24;
+ h &= ~g;
+ }
+ return h;
+#elif HASH_PERL
+ register int val = 0;
+
+ while ((c = *string++) != '\0') {
+ val += c;
+ val += (val << 10);
+ val ^= (val >> 6);
+ }
+ val += (val << 3);
+ val ^= (val >> 11);
+
+ return val + (val << 15);
+#else
+ register int val = 0;
+
+ while ((c = *string++) != '\0') {
+ val = val*997 + c;
+ }
+
+ return val + (val>>5);
+#endif
+}
+
+static int
+numcmp(x, y)
+ long x, y;
+{
+ return x != y;
+}
+
+static int
+numhash(n)
+ long n;
+{
+ return n;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-27 05:56:36 +0000