termux-x11/app/src/main/jni/libxkbcommon/xkbcommon/src/atom.c

194 lines
7.0 KiB
C

/***********************************************************
* Copyright 1987, 1998 The Open Group
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation.
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of The Open Group shall not be
* used in advertising or otherwise to promote the sale, use or other dealings
* in this Software without prior written authorization from The Open Group.
*
*
* Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
*
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appear in all copies and that
* both that copyright notice and this permission notice appear in
* supporting documentation, and that the name of Digital not be
* used in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission.
*
* DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
* ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
* DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
* ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
* ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*
******************************************************************/
/************************************************************
* Copyright 1994 by Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting
* documentation, and that the name of Silicon Graphics not be
* used in advertising or publicity pertaining to distribution
* of the software without specific prior written permission.
* Silicon Graphics makes no representation about the suitability
* of this software for any purpose. It is provided "as is"
* without any express or implied warranty.
*
* SILICON GRAPHICS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
* GRAPHICS BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH
* THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
********************************************************/
#include "config.h"
#include <assert.h>
#include <inttypes.h>
#include <stdbool.h>
#include <string.h>
#include "atom.h"
#include "darray.h"
#include "utils.h"
/* FNV-1a (http://www.isthe.com/chongo/tech/comp/fnv/). */
static inline uint32_t
hash_buf(const char *string, size_t len)
{
uint32_t hash = 2166136261u;
for (size_t i = 0; i < (len + 1) / 2; i++) {
hash ^= (uint8_t) string[i];
hash *= 0x01000193;
hash ^= (uint8_t) string[len - 1 - i];
hash *= 0x01000193;
}
return hash;
}
/*
* The atom table is an insert-only linear probing hash table
* mapping strings to atoms. Another array maps the atoms to
* strings. The atom value is the position in the strings array.
*/
struct atom_table {
xkb_atom_t *index;
size_t index_size;
darray(char *) strings;
};
struct atom_table *
atom_table_new(void)
{
struct atom_table *table = calloc(1, sizeof(*table));
if (!table)
return NULL;
darray_init(table->strings);
darray_append(table->strings, NULL);
table->index_size = 4;
table->index = calloc(table->index_size, sizeof(*table->index));
return table;
}
void
atom_table_free(struct atom_table *table)
{
if (!table)
return;
char **string;
darray_foreach(string, table->strings)
free(*string);
darray_free(table->strings);
free(table->index);
free(table);
}
const char *
atom_text(struct atom_table *table, xkb_atom_t atom)
{
assert(atom < darray_size(table->strings));
return darray_item(table->strings, atom);
}
xkb_atom_t
atom_intern(struct atom_table *table, const char *string, size_t len, bool add)
{
if (darray_size(table->strings) > 0.80 * table->index_size) {
table->index_size *= 2;
table->index = realloc(table->index, table->index_size * sizeof(*table->index));
memset(table->index, 0, table->index_size * sizeof(*table->index));
for (size_t j = 1; j < darray_size(table->strings); j++) {
const char *s = darray_item(table->strings, j);
uint32_t hash = hash_buf(s, strlen(s));
for (size_t i = 0; i < table->index_size; i++) {
size_t index_pos = (hash + i) & (table->index_size - 1);
if (index_pos == 0)
continue;
xkb_atom_t atom = table->index[index_pos];
if (atom == XKB_ATOM_NONE) {
table->index[index_pos] = j;
break;
}
}
}
}
uint32_t hash = hash_buf(string, len);
for (size_t i = 0; i < table->index_size; i++) {
size_t index_pos = (hash + i) & (table->index_size - 1);
if (index_pos == 0)
continue;
xkb_atom_t existing_atom = table->index[index_pos];
if (existing_atom == XKB_ATOM_NONE) {
if (add) {
xkb_atom_t new_atom = darray_size(table->strings);
darray_append(table->strings, strndup(string, len));
table->index[index_pos] = new_atom;
return new_atom;
} else {
return XKB_ATOM_NONE;
}
}
const char *existing_value = darray_item(table->strings, existing_atom);
if (strncmp(existing_value, string, len) == 0 && existing_value[len] == '\0')
return existing_atom;
}
assert(!"couldn't find an empty slot during probing");
}