server: Add a helper function for hashing a Unicode string.

Signed-off-by: Alexandre Julliard <julliard@winehq.org>
This commit is contained in:
Alexandre Julliard 2020-03-24 12:48:26 +01:00
parent 5721d5f8da
commit 6db1232567
4 changed files with 15 additions and 22 deletions

View File

@ -163,15 +163,6 @@ static atom_t add_atom_entry( struct atom_table *table, struct atom_entry *entry
return entry->atom;
}
/* compute the hash code for a string */
static unsigned short atom_hash( struct atom_table *table, const struct unicode_str *str )
{
unsigned int i;
unsigned short hash = 0;
for (i = 0; i < str->len / sizeof(WCHAR); i++) hash ^= toupperW(str->str[i]) + i;
return hash % table->entries_count;
}
/* dump an atom table */
static void atom_table_dump( struct object *obj, int verbose )
{
@ -224,7 +215,7 @@ static struct atom_entry *find_atom_entry( struct atom_table *table, const struc
static atom_t add_atom( struct atom_table *table, const struct unicode_str *str )
{
struct atom_entry *entry;
unsigned short hash = atom_hash( table, str );
unsigned short hash = hash_strW( str->str, str->len, table->entries_count );
atom_t atom = 0;
if (!str->len)
@ -293,7 +284,8 @@ static atom_t find_atom( struct atom_table *table, const struct unicode_str *str
set_error( STATUS_INVALID_PARAMETER );
return 0;
}
if (table && (entry = find_atom_entry( table, str, atom_hash(table, str) )))
if (table && (entry = find_atom_entry( table, str,
hash_strW( str->str, str->len, table->entries_count ))))
return entry->atom;
set_error( STATUS_OBJECT_NAME_NOT_FOUND );
return 0;
@ -350,7 +342,7 @@ atom_t find_global_atom( struct winstation *winstation, const struct unicode_str
struct atom_entry *entry;
if (!str->len || str->len > MAX_ATOM_LEN || !table) return 0;
if ((entry = find_atom_entry( table, str, atom_hash(table, str) )))
if ((entry = find_atom_entry( table, str, hash_strW( str->str, str->len, table->entries_count ))))
return entry->atom;
return 0;
}

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@ -127,17 +127,9 @@ void *memdup( const void *data, size_t len )
/*****************************************************************/
static int get_name_hash( const struct namespace *namespace, const WCHAR *name, data_size_t len )
{
WCHAR hash = 0;
len /= sizeof(WCHAR);
while (len--) hash ^= tolowerW(*name++);
return hash % namespace->hash_size;
}
void namespace_add( struct namespace *namespace, struct object_name *ptr )
{
int hash = get_name_hash( namespace, ptr->name, ptr->len );
unsigned int hash = hash_strW( ptr->name, ptr->len, namespace->hash_size );
list_add_head( &namespace->names[hash], &ptr->entry );
}
@ -450,7 +442,7 @@ struct object *find_object( const struct namespace *namespace, const struct unic
if (!name || !name->len) return NULL;
list = &namespace->names[ get_name_hash( namespace, name->str, name->len ) ];
list = &namespace->names[ hash_strW( name->str, name->len, namespace->hash_size ) ];
LIST_FOR_EACH( p, list )
{
const struct object_name *ptr = LIST_ENTRY( p, struct object_name, entry );

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@ -66,6 +66,14 @@ int memicmp_strW( const WCHAR *str1, const WCHAR *str2, data_size_t len )
return ret;
}
unsigned int hash_strW( const WCHAR *str, data_size_t len, unsigned int hash_size )
{
unsigned int i, hash = 0;
for (i = 0; i < len / sizeof(WCHAR); i++) hash = hash * 65599 + to_lower( str[i] );
return hash % hash_size;
}
WCHAR *ascii_to_unicode_str( const char *str, struct unicode_str *ret )
{
data_size_t i, len = strlen(str);

View File

@ -28,6 +28,7 @@
#include "object.h"
extern int memicmp_strW( const WCHAR *str1, const WCHAR *str2, data_size_t len );
extern unsigned int hash_strW( const WCHAR *str, data_size_t len, unsigned int hash_size );
extern WCHAR *ascii_to_unicode_str( const char *str, struct unicode_str *ret );
extern int parse_strW( WCHAR *buffer, data_size_t *len, const char *src, char endchar );
extern int dump_strW( const WCHAR *str, data_size_t len, FILE *f, const char escape[2] );