Sweden-Number/server/atom.c

342 lines
9.8 KiB
C

/*
* Server-side atom management
*
* Copyright (C) 1999, 2000 Alexandre Julliard
* Copyright (C) 2000 Turchanov Sergei
*/
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "unicode.h"
#include "request.h"
#include "object.h"
#include "process.h"
#define HASH_SIZE 37
#define MIN_HASH_SIZE 4
#define MAX_HASH_SIZE 0x200
#define MAX_ATOM_LEN 255
#define MIN_STR_ATOM 0xc000
#define MAX_ATOMS 0x4000
struct atom_entry
{
struct atom_entry *next; /* hash table list */
struct atom_entry *prev; /* hash table list */
int count; /* reference count */
int hash; /* string hash */
atom_t atom; /* atom handle */
WCHAR str[1]; /* atom string */
};
struct atom_table
{
struct object obj; /* object header */
int count; /* count of atom handles */
int last; /* last handle in-use */
struct atom_entry **handles; /* atom handles */
int entries_count; /* humber of hash entries */
struct atom_entry **entries; /* hash table entries */
};
static void atom_table_dump( struct object *obj, int verbose );
static void atom_table_destroy( struct object *obj );
static const struct object_ops atom_table_ops =
{
sizeof(struct atom_table), /* size */
atom_table_dump, /* dump */
no_add_queue, /* add_queue */
NULL, /* remove_queue */
NULL, /* signaled */
NULL, /* satified */
NULL, /* get_poll_events */
NULL, /* poll_event */
no_get_fd, /* get_fd */
no_flush, /* flush */
no_get_file_info, /* get_file_info */
NULL, /* queue_async */
atom_table_destroy /* destroy */
};
static struct atom_table *global_table;
/* copy an atom name from the request to a temporary area */
static const WCHAR *copy_request_name(void)
{
static WCHAR buffer[MAX_ATOM_LEN+1];
const WCHAR *str = get_req_data();
size_t len = get_req_data_size();
if (len > MAX_ATOM_LEN*sizeof(WCHAR))
{
set_error( STATUS_INVALID_PARAMETER );
return NULL;
}
memcpy( buffer, str, len );
buffer[len / sizeof(WCHAR)] = 0;
return buffer;
}
/* create an atom table */
static struct atom_table *create_table(int entries_count)
{
struct atom_table *table;
if ((table = alloc_object( &atom_table_ops, -1 )))
{
if ((entries_count < MIN_HASH_SIZE) ||
(entries_count > MAX_HASH_SIZE)) entries_count = HASH_SIZE;
table->entries_count = entries_count;
if (!(table->entries = malloc( sizeof(*table->entries) * table->entries_count )))
{
set_error( STATUS_NO_MEMORY );
goto fail;
}
memset( table->entries, 0, sizeof(*table->entries) * table->entries_count );
table->count = 64;
table->last = -1;
if ((table->handles = mem_alloc( sizeof(*table->handles) * table->count )))
return table;
fail:
release_object( table );
table = NULL;
}
return table;
}
/* retrieve an entry pointer from its atom */
static struct atom_entry *get_atom_entry( struct atom_table *table, atom_t atom )
{
struct atom_entry *entry = NULL;
if (table && (atom >= MIN_STR_ATOM) && (atom <= MIN_STR_ATOM + table->last))
entry = table->handles[atom - MIN_STR_ATOM];
if (!entry) set_error( STATUS_INVALID_HANDLE );
return entry;
}
/* add an atom entry in the table and return its handle */
static atom_t add_atom_entry( struct atom_table *table, struct atom_entry *entry )
{
int i;
for (i = 0; i <= table->last; i++)
if (!table->handles[i]) goto found;
if (i == table->count)
{
struct atom_entry **new_table = NULL;
int new_size = table->count + table->count / 2;
if (new_size > MAX_ATOMS) new_size = MAX_ATOMS;
if (new_size > table->count)
new_table = realloc( table->handles, sizeof(*table->handles) * new_size );
if (!new_table)
{
set_error( STATUS_NO_MEMORY );
return 0;
}
table->count = new_size;
table->handles = new_table;
}
table->last = i;
found:
table->handles[i] = entry;
entry->atom = i + MIN_STR_ATOM;
return entry->atom;
}
/* compute the hash code for a string */
static int atom_hash( struct atom_table *table, const WCHAR *str )
{
int i;
WCHAR hash = 0;
for (i = 0; str[i]; i++) hash ^= toupperW(str[i]) + i;
return hash % table->entries_count;
}
/* dump an atom table */
static void atom_table_dump( struct object *obj, int verbose )
{
int i;
struct atom_table *table = (struct atom_table *)obj;
assert( obj->ops == &atom_table_ops );
fprintf( stderr, "Atom table size=%d entries=%d\n",
table->last + 1, table->entries_count );
if (!verbose) return;
for (i = 0; i <= table->last; i++)
{
struct atom_entry *entry = table->handles[i];
if (!entry) continue;
fprintf( stderr, " %04x: ref=%d hash=%d \"", entry->atom, entry->count, entry->hash );
dump_strW( entry->str, strlenW(entry->str), stderr, "\"\"");
fprintf( stderr, "\"\n" );
}
}
/* destroy the atom table */
static void atom_table_destroy( struct object *obj )
{
int i;
struct atom_table *table = (struct atom_table *)obj;
assert( obj->ops == &atom_table_ops );
if (table->handles)
{
for (i = 0; i <= table->last; i++) free( table->handles[i] );
free( table->handles );
}
if (table->entries) free( table->entries );
}
/* find an atom entry in its hash list */
static struct atom_entry *find_atom_entry( struct atom_table *table, const WCHAR *str, int hash )
{
struct atom_entry *entry = table->entries[hash];
while (entry)
{
if (!strcmpiW( entry->str, str )) break;
entry = entry->next;
}
return entry;
}
/* close the atom table; used on server exit */
void close_atom_table(void)
{
if (global_table) release_object( global_table );
}
/* add an atom to the table */
static atom_t add_atom( struct atom_table *table, const WCHAR *str )
{
struct atom_entry *entry;
int hash = atom_hash( table, str );
atom_t atom = 0;
if (!*str)
{
set_error( STATUS_OBJECT_NAME_INVALID );
return 0;
}
if ((entry = find_atom_entry( table, str, hash ))) /* exists already */
{
entry->count++;
return entry->atom;
}
if ((entry = mem_alloc( sizeof(*entry) + strlenW(str) * sizeof(WCHAR) )))
{
if ((atom = add_atom_entry( table, entry )))
{
entry->prev = NULL;
if ((entry->next = table->entries[hash])) entry->next->prev = entry;
table->entries[hash] = entry;
entry->count = 1;
entry->hash = hash;
strcpyW( entry->str, str );
}
else free( entry );
}
else set_error( STATUS_NO_MEMORY );
return atom;
}
/* delete an atom from the table */
static void delete_atom( struct atom_table *table, atom_t atom )
{
struct atom_entry *entry = get_atom_entry( table, atom );
if (entry && !--entry->count)
{
if (entry->next) entry->next->prev = entry->prev;
if (entry->prev) entry->prev->next = entry->next;
else table->entries[entry->hash] = entry->next;
table->handles[atom - MIN_STR_ATOM] = NULL;
free( entry );
}
}
/* find an atom in the table */
static atom_t find_atom( struct atom_table *table, const WCHAR *str )
{
struct atom_entry *entry;
if (table && ((entry = find_atom_entry( table, str, atom_hash(table, str) ))))
return entry->atom;
if (!*str) set_error( STATUS_OBJECT_NAME_INVALID );
else set_error( STATUS_OBJECT_NAME_NOT_FOUND );
return 0;
}
/* increment the ref count of a global atom; used for window properties */
int grab_global_atom( atom_t atom )
{
if (atom >= MIN_STR_ATOM)
{
struct atom_entry *entry = get_atom_entry( global_table, atom );
if (entry) entry->count++;
return (entry != NULL);
}
else return 1;
}
/* decrement the ref count of a global atom; used for window properties */
void release_global_atom( atom_t atom )
{
if (atom >= MIN_STR_ATOM) delete_atom( global_table, atom );
}
/* add a global atom */
DECL_HANDLER(add_atom)
{
struct atom_table **table_ptr = req->local ? &current->process->atom_table : &global_table;
if (!*table_ptr) *table_ptr = create_table(0);
if (*table_ptr)
{
const WCHAR *name = copy_request_name();
if (name) reply->atom = add_atom( *table_ptr, name );
}
}
/* delete a global atom */
DECL_HANDLER(delete_atom)
{
delete_atom( req->local ? current->process->atom_table : global_table, req->atom );
}
/* find a global atom */
DECL_HANDLER(find_atom)
{
const WCHAR *name = copy_request_name();
if (name)
reply->atom = find_atom( req->local ? current->process->atom_table : global_table, name );
}
/* get global atom name */
DECL_HANDLER(get_atom_name)
{
struct atom_entry *entry;
size_t len = 0;
reply->count = -1;
if ((entry = get_atom_entry( req->local ? current->process->atom_table : global_table,
req->atom )))
{
reply->count = entry->count;
len = strlenW( entry->str ) * sizeof(WCHAR);
if (len <= get_reply_max_size()) set_reply_data( entry->str, len );
else set_error( STATUS_BUFFER_OVERFLOW );
}
}
/* init the process atom table */
DECL_HANDLER(init_atom_table)
{
if (!current->process->atom_table)
current->process->atom_table = create_table( req->entries );
}