Check for NULL flipchain and just return the current surface if it

[wine/multimedia.git] / server / registry.c

/*
 * Server-side registry management
 *
 * Copyright (C) 1999 Alexandre Julliard
 */

/* To do:
 * - behavior with deleted keys
 * - values larger than request buffer
 * - symbolic links
 */

#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <unistd.h>
#include <pwd.h>
#include "object.h"
#include "handle.h"
#include "request.h"
#include "unicode.h"

#include "winbase.h"
#include "winreg.h"
#include "winnt.h" /* registry definitions */


/* a registry key */
struct key
{
    struct object     obj;         /* object header */
    WCHAR            *name;        /* key name */
    WCHAR            *class;       /* key class */
    struct key       *parent;      /* parent key */
    int               last_subkey; /* last in use subkey */
    int               nb_subkeys;  /* count of allocated subkeys */
    struct key      **subkeys;     /* subkeys array */
    int               last_value;  /* last in use value */
    int               nb_values;   /* count of allocated values in array */
    struct key_value *values;      /* values array */
    short             flags;       /* flags */
    short             level;       /* saving level */
    time_t            modif;       /* last modification time */
};

/* key flags */
#define KEY_VOLATILE 0x0001  /* key is volatile (not saved to disk) */
#define KEY_DELETED  0x0002  /* key has been deleted */
#define KEY_ROOT     0x0004  /* key is a root key */

/* a key value */
struct key_value
{
    WCHAR            *name;    /* value name */
    int               type;    /* value type */
    size_t            len;     /* value data length in bytes */
    void             *data;    /* pointer to value data */
};

#define MIN_SUBKEYS  8   /* min. number of allocated subkeys per key */
#define MIN_VALUES   8   /* min. number of allocated values per key */


/* the root keys */
#define HKEY_ROOT_FIRST   HKEY_CLASSES_ROOT
#define HKEY_ROOT_LAST    HKEY_DYN_DATA
#define NB_ROOT_KEYS      (HKEY_ROOT_LAST - HKEY_ROOT_FIRST + 1)
#define IS_ROOT_HKEY(h)   (((h) >= HKEY_ROOT_FIRST) && ((h) <= HKEY_ROOT_LAST))
static struct key *root_keys[NB_ROOT_KEYS];


/* keys saving level */
/* current_level is the level that is put into all newly created or modified keys */
/* saving_level is the minimum level that a key needs in order to get saved */
static int current_level;
static int saving_level;

static struct timeval next_save_time;           /* absolute time of next periodic save */
static int save_period;                         /* delay between periodic saves (ms) */
static struct timeout_user *save_timeout_user;  /* saving timer */

/* information about where to save a registry branch */
struct save_branch_info
{
    struct key  *key;
    char        *path;
};

#define MAX_SAVE_BRANCH_INFO 8
static int save_branch_count;
static struct save_branch_info save_branch_info[MAX_SAVE_BRANCH_INFO];


/* information about a file being loaded */
struct file_load_info
{
    FILE *file;    /* input file */
    char *buffer;  /* line buffer */
    int   len;     /* buffer length */
    int   line;    /* current input line */
    char *tmp;     /* temp buffer to use while parsing input */
    int   tmplen;  /* length of temp buffer */
};


static void key_dump( struct object *obj, int verbose );
static void key_destroy( struct object *obj );

static const struct object_ops key_ops =
{
    sizeof(struct key),      /* size */
    key_dump,                /* dump */
    no_add_queue,            /* add_queue */
    NULL,                    /* remove_queue */
    NULL,                    /* signaled */
    NULL,                    /* satisfied */
    NULL,                    /* get_poll_events */
    NULL,                    /* poll_event */
    no_read_fd,              /* get_read_fd */
    no_write_fd,             /* get_write_fd */
    no_flush,                /* flush */
    no_get_file_info,        /* get_file_info */
    key_destroy              /* destroy */
};


/*
 * The registry text file format v2 used by this code is similar to the one
 * used by REGEDIT import/export functionality, with the following differences:
 * - strings and key names can contain \x escapes for Unicode
 * - key names use escapes too in order to support Unicode
 * - the modification time optionally follows the key name
 * - REG_EXPAND_SZ and REG_MULTI_SZ are saved as strings instead of hex
 */

static inline char to_hex( char ch )
{
    if (isdigit(ch)) return ch - '0';
    return tolower(ch) - 'a' + 10;
}

/* dump the full path of a key */
static void dump_path( struct key *key, struct key *base, FILE *f )
{
    if (key->parent && key != base)
    {
        dump_path( key->parent, base, f );
        fprintf( f, "\\\\" );
    }
    dump_strW( key->name, strlenW(key->name), f, "[]" );
}

/* dump a value to a text file */
static void dump_value( struct key_value *value, FILE *f )
{
    int i, count;

    if (value->name[0])
    {
        fputc( '\"', f );
        count = 1 + dump_strW( value->name, strlenW(value->name), f, "\"\"" );
        count += fprintf( f, "\"=" );
    }
    else count = fprintf( f, "@=" );

    switch(value->type)
    {
    case REG_SZ:
    case REG_EXPAND_SZ:
    case REG_MULTI_SZ:
        if (value->type != REG_SZ) fprintf( f, "str(%d):", value->type );
        fputc( '\"', f );
        if (value->data) dump_strW( (WCHAR *)value->data, value->len / sizeof(WCHAR), f, "\"\"" );
        fputc( '\"', f );
        break;
    case REG_DWORD:
        if (value->len == sizeof(DWORD))
        {
            DWORD dw;
            memcpy( &dw, value->data, sizeof(DWORD) );
            fprintf( f, "dword:%08lx", dw );
            break;
        }
        /* else fall through */
    default:
        if (value->type == REG_BINARY) count += fprintf( f, "hex:" );
        else count += fprintf( f, "hex(%x):", value->type );
        for (i = 0; i < value->len; i++)
        {
            count += fprintf( f, "%02x", *((unsigned char *)value->data + i) );
            if (i < value->len-1)
            {
                fputc( ',', f );
                if (++count > 76)
                {
                    fprintf( f, "\\\n  " );
                    count = 2;
                }
            }
        }
        break;
    }
    fputc( '\n', f );
}

/* save a registry and all its subkeys to a text file */
static void save_subkeys( struct key *key, struct key *base, FILE *f )
{
    int i;

    if (key->flags & KEY_VOLATILE) return;
    /* save key if it has the proper level, and has either some values or no subkeys */
    /* keys with no values but subkeys are saved implicitly by saving the subkeys */
    if ((key->level >= saving_level) && ((key->last_value >= 0) || (key->last_subkey == -1)))
    {
        fprintf( f, "\n[" );
        dump_path( key, base, f );
        fprintf( f, "] %ld\n", key->modif );
        for (i = 0; i <= key->last_value; i++) dump_value( &key->values[i], f );
    }
    for (i = 0; i <= key->last_subkey; i++) save_subkeys( key->subkeys[i], base, f );
}

static void dump_operation( struct key *key, struct key_value *value, const char *op )
{
    fprintf( stderr, "%s key ", op );
    if (key) dump_path( key, NULL, stderr );
    else fprintf( stderr, "ERROR" );
    if (value)
    {
        fprintf( stderr, " value ");
        dump_value( value, stderr );
    }
    else fprintf( stderr, "\n" );
}

static void key_dump( struct object *obj, int verbose )
{
    struct key *key = (struct key *)obj;
    assert( obj->ops == &key_ops );
    fprintf( stderr, "Key flags=%x ", key->flags );
    dump_path( key, NULL, stderr );
    fprintf( stderr, "\n" );
}

static void key_destroy( struct object *obj )
{
    int i;
    struct key *key = (struct key *)obj;
    assert( obj->ops == &key_ops );

    if (key->name) free( key->name );
    if (key->class) free( key->class );
    for (i = 0; i <= key->last_value; i++)
    {
        free( key->values[i].name );
        if (key->values[i].data) free( key->values[i].data );
    }
    for (i = 0; i <= key->last_subkey; i++)
    {
        key->subkeys[i]->parent = NULL;
        release_object( key->subkeys[i] );
    }
}

/* duplicate a key path from the request buffer */
/* returns a pointer to a static buffer, so only useable once per request */
static WCHAR *copy_path( const path_t path )
{
    static WCHAR buffer[MAX_PATH+1];
    WCHAR *p = buffer;

    while (p < buffer + sizeof(buffer) - 1) if (!(*p++ = *path++)) break;
    *p = 0;
    return buffer;
}

/* return the next token in a given path */
/* returns a pointer to a static buffer, so only useable once per request */
static WCHAR *get_path_token( const WCHAR *initpath, size_t maxlen )
{
    static const WCHAR *path;
    static const WCHAR *end;
    static WCHAR buffer[MAX_PATH+1];
    WCHAR *p = buffer;

    if (initpath)
    {
        path = initpath;
        end  = path + maxlen / sizeof(WCHAR);
    }
    while ((path < end) && (*path == '\\')) path++;
    while ((path < end) && (p < buffer + sizeof(buffer) - 1))
    {
        WCHAR ch = *path;
        if (!ch || (ch == '\\')) break;
        *p++ = ch;
        path++;
    }
    *p = 0;
    return buffer;
}

/* duplicate a Unicode string from the request buffer */
static WCHAR *req_strdupW( const void *req, const WCHAR *str )
{
    WCHAR *name;
    size_t len = get_req_strlenW( req, str );
    if ((name = mem_alloc( (len + 1) * sizeof(WCHAR) )) != NULL)
    {
        memcpy( name, str, len * sizeof(WCHAR) );
        name[len] = 0;
    }
    return name;
}

/* allocate a key object */
static struct key *alloc_key( const WCHAR *name, time_t modif )
{
    struct key *key;
    if ((key = (struct key *)alloc_object( &key_ops, -1 )))
    {
        key->class       = NULL;
        key->flags       = 0;
        key->last_subkey = -1;
        key->nb_subkeys  = 0;
        key->subkeys     = NULL;
        key->nb_values   = 0;
        key->last_value  = -1;
        key->values      = NULL;
        key->level       = current_level;
        key->modif       = modif;
        key->parent      = NULL;
        if (!(key->name = strdupW( name )))
        {
            release_object( key );
            key = NULL;
        }
    }
    return key;
}

/* update key modification time */
static void touch_key( struct key *key )
{
    key->modif = time(NULL);
    key->level = max( key->level, current_level );
}

/* try to grow the array of subkeys; return 1 if OK, 0 on error */
static int grow_subkeys( struct key *key )
{
    struct key **new_subkeys;
    int nb_subkeys;

    if (key->nb_subkeys)
    {
        nb_subkeys = key->nb_subkeys + (key->nb_subkeys / 2);  /* grow by 50% */
        if (!(new_subkeys = realloc( key->subkeys, nb_subkeys * sizeof(*new_subkeys) )))
        {
            set_error( STATUS_NO_MEMORY );
            return 0;
        }
    }
    else
    {
        nb_subkeys = MIN_VALUES;
        if (!(new_subkeys = mem_alloc( nb_subkeys * sizeof(*new_subkeys) ))) return 0;
    }
    key->subkeys    = new_subkeys;
    key->nb_subkeys = nb_subkeys;
    return 1;
}

/* allocate a subkey for a given key, and return its index */
static struct key *alloc_subkey( struct key *parent, const WCHAR *name, int index, time_t modif )
{
    struct key *key;
    int i;

    if (parent->last_subkey + 1 == parent->nb_subkeys)
    {
        /* need to grow the array */
        if (!grow_subkeys( parent )) return NULL;
    }
    if ((key = alloc_key( name, modif )) != NULL)
    {
        key->parent = parent;
        for (i = ++parent->last_subkey; i > index; i--)
            parent->subkeys[i] = parent->subkeys[i-1];
        parent->subkeys[index] = key;
    }
    return key;
}

/* free a subkey of a given key */
static void free_subkey( struct key *parent, int index )
{
    struct key *key;
    int i, nb_subkeys;

    assert( index >= 0 );
    assert( index <= parent->last_subkey );

    key = parent->subkeys[index];
    for (i = index; i < parent->last_subkey; i++) parent->subkeys[i] = parent->subkeys[i + 1];
    parent->last_subkey--;
    key->flags |= KEY_DELETED;
    key->parent = NULL;
    release_object( key );
    
    /* try to shrink the array */
    nb_subkeys = key->nb_subkeys;
    if (nb_subkeys > MIN_SUBKEYS && key->last_subkey < nb_subkeys / 2)
    {
        struct key **new_subkeys;
        nb_subkeys -= nb_subkeys / 3;  /* shrink by 33% */
        if (nb_subkeys < MIN_SUBKEYS) nb_subkeys = MIN_SUBKEYS;
        if (!(new_subkeys = realloc( key->subkeys, nb_subkeys * sizeof(*new_subkeys) ))) return;
        key->subkeys = new_subkeys;
        key->nb_subkeys = nb_subkeys;
    }
}

/* find the named child of a given key and return its index */
static struct key *find_subkey( struct key *key, const WCHAR *name, int *index )
{
    int i, min, max, res;

    min = 0;
    max = key->last_subkey;
    while (min <= max)
    {
        i = (min + max) / 2;
        if (!(res = strcmpiW( key->subkeys[i]->name, name )))
        {
            *index = i;
            return key->subkeys[i];
        }
        if (res > 0) max = i - 1;
        else min = i + 1;
    }
    *index = min;  /* this is where we should insert it */
    return NULL;
}

/* open a subkey */
static struct key *open_key( struct key *key, const WCHAR *name, size_t maxlen )
{
    int index;
    WCHAR *path;

    path = get_path_token( name, maxlen );
    while (*path)
    {
        if (!(key = find_subkey( key, path, &index )))
        {
            set_error( STATUS_OBJECT_NAME_NOT_FOUND );
            break;
        }
        path = get_path_token( NULL, 0 );
    }

    if (debug_level > 1) dump_operation( key, NULL, "Open" );
    if (key) grab_object( key );
    return key;
}

/* create a subkey */
static struct key *create_key( struct key *key, const WCHAR *name, size_t maxlen, WCHAR *class,
                               unsigned int options, time_t modif, int *created )
{
    struct key *base;
    int base_idx, index, flags = 0;
    WCHAR *path;

    if (key->flags & KEY_DELETED) /* we cannot create a subkey under a deleted key */
    {
        set_error( STATUS_KEY_DELETED );
        return NULL;
    }
    if (options & REG_OPTION_VOLATILE) flags |= KEY_VOLATILE;
    else if (key->flags & KEY_VOLATILE)
    {
        set_error( STATUS_CHILD_MUST_BE_VOLATILE );
        return NULL;
    }

    path = get_path_token( name, maxlen );
    *created = 0;
    while (*path)
    {
        struct key *subkey;
        if (!(subkey = find_subkey( key, path, &index ))) break;
        key = subkey;
        path = get_path_token( NULL, 0 );
    }

    /* create the remaining part */

    if (!*path) goto done;
    *created = 1;
    base = key;
    base_idx = index;
    key = alloc_subkey( key, path, index, modif );
    while (key)
    {
        key->flags |= flags;
        path = get_path_token( NULL, 0 );
        if (!*path) goto done;
        /* we know the index is always 0 in a new key */
        key = alloc_subkey( key, path, 0, modif );
    }
    if (base_idx != -1) free_subkey( base, base_idx );
    return NULL;

 done:
    if (debug_level > 1) dump_operation( key, NULL, "Create" );
    if (class) key->class = strdupW(class);
    grab_object( key );
    return key;
}

/* find a subkey of a given key by its index */
static void enum_key( struct key *parent, int index, WCHAR *name, WCHAR *class, time_t *modif )
{
    struct key *key;

    if ((index < 0) || (index > parent->last_subkey)) set_error( STATUS_NO_MORE_ENTRIES );
    else
    {
        key = parent->subkeys[index];
        *modif = key->modif;
        strcpyW( name, key->name );
        if (key->class) strcpyW( class, key->class );  /* FIXME: length */
        else *class = 0;
        if (debug_level > 1) dump_operation( key, NULL, "Enum" );
    }
}

/* query information about a key */
static void query_key( struct key *key, struct query_key_info_request *req )
{
    int i, len;
    int max_subkey = 0, max_class = 0;
    int max_value = 0, max_data = 0;

    for (i = 0; i <= key->last_subkey; i++)
    {
        struct key *subkey = key->subkeys[i];
        len = strlenW( subkey->name );
        if (len > max_subkey) max_subkey = len;
        if (!subkey->class) continue;
        len = strlenW( subkey->class );
        if (len > max_class) max_class = len;
    }
    for (i = 0; i <= key->last_value; i++)
    {
        len = strlenW( key->values[i].name );
        if (len > max_value) max_value = len;
        len = key->values[i].len;
        if (len > max_data) max_data = len;
    }
    req->subkeys    = key->last_subkey + 1;
    req->max_subkey = max_subkey;
    req->max_class  = max_class;
    req->values     = key->last_value + 1;
    req->max_value  = max_value;
    req->max_data   = max_data;
    req->modif      = key->modif;
    strcpyW( req->name, key->name);
    if (key->class) strcpyW( req->class, key->class );  /* FIXME: length */
    else req->class[0] = 0;
    if (debug_level > 1) dump_operation( key, NULL, "Query" );
}

/* delete a key and its values */
static void delete_key( struct key *key, const WCHAR *name, size_t maxlen )
{
    int index;
    struct key *parent;
    WCHAR *path;

    path = get_path_token( name, maxlen );
    if (!*path)
    {
        /* deleting this key, must find parent and index */
        if (key->flags & KEY_ROOT)
        {
            set_error( STATUS_ACCESS_DENIED );
            return;
        }
        if (!(parent = key->parent) || (key->flags & KEY_DELETED))
        {
            set_error( STATUS_KEY_DELETED );
            return;
        }
        for (index = 0; index <= parent->last_subkey; index++)
            if (parent->subkeys[index] == key) break;
        assert( index <= parent->last_subkey );
    }
    else while (*path)
    {
        parent = key;
        if (!(key = find_subkey( parent, path, &index )))
        {
            set_error( STATUS_OBJECT_NAME_NOT_FOUND );
            return;
        }
        path = get_path_token( NULL, 0 );
    }

    /* we can only delete a key that has no subkeys (FIXME) */
    if ((key->flags & KEY_ROOT) || (key->last_subkey >= 0))
    {
        set_error( STATUS_ACCESS_DENIED );
        return;
    }
    if (debug_level > 1) dump_operation( key, NULL, "Delete" );
    free_subkey( parent, index );
    touch_key( parent );
}

/* try to grow the array of values; return 1 if OK, 0 on error */
static int grow_values( struct key *key )
{
    struct key_value *new_val;
    int nb_values;

    if (key->nb_values)
    {
        nb_values = key->nb_values + (key->nb_values / 2);  /* grow by 50% */
        if (!(new_val = realloc( key->values, nb_values * sizeof(*new_val) )))
        {
            set_error( STATUS_NO_MEMORY );
            return 0;
        }
    }
    else
    {
        nb_values = MIN_VALUES;
        if (!(new_val = mem_alloc( nb_values * sizeof(*new_val) ))) return 0;
    }
    key->values = new_val;
    key->nb_values = nb_values;
    return 1;
}

/* find the named value of a given key and return its index in the array */
static struct key_value *find_value( const struct key *key, const WCHAR *name, int *index )
{
    int i, min, max, res;

    min = 0;
    max = key->last_value;
    while (min <= max)
    {
        i = (min + max) / 2;
        if (!(res = strcmpiW( key->values[i].name, name )))
        {
            *index = i;
            return &key->values[i];
        }
        if (res > 0) max = i - 1;
        else min = i + 1;
    }
    *index = min;  /* this is where we should insert it */
    return NULL;
}

/* insert a new value or return a pointer to an existing one */
static struct key_value *insert_value( struct key *key, const WCHAR *name )
{
    struct key_value *value;
    WCHAR *new_name;
    int i, index;

    if (!(value = find_value( key, name, &index )))
    {
        /* not found, add it */
        if (key->last_value + 1 == key->nb_values)
        {
            if (!grow_values( key )) return NULL;
        }
        if (!(new_name = strdupW(name))) return NULL;
        for (i = ++key->last_value; i > index; i--) key->values[i] = key->values[i - 1];
        value = &key->values[index];
        value->name = new_name;
        value->len  = 0;
        value->data = NULL;
    }
    return value;
}

/* set a key value */
static void set_value( struct key *key, WCHAR *name, int type, unsigned int total_len,
                       unsigned int offset, unsigned int data_len, void *data )
{
    struct key_value *value;
    void *ptr = NULL;

    if (data_len + offset > total_len)
    {
        set_error( STATUS_INVALID_PARAMETER );
        return;
    }

    if (offset)  /* adding data to an existing value */
    {
        int index;
        if (!(value = find_value( key, name, &index )))
        {
            set_error( STATUS_OBJECT_NAME_NOT_FOUND );
            return;
        }
        if (value->len != total_len)
        {
            set_error( STATUS_INVALID_PARAMETER );
            return;
        }
        memcpy( (char *)value->data + offset, data, data_len );
        if (debug_level > 1) dump_operation( key, value, "Set" );
        return;
    }

    /* first copy the data */
    if (total_len)
    {
        if (!(ptr = mem_alloc( total_len ))) return;
        memcpy( ptr, data, data_len );
        if (data_len < total_len) memset( (char *)ptr + data_len, 0, total_len - data_len );
    }

    if (!(value = insert_value( key, name )))
    {
        if (ptr) free( ptr );
        return;
    }
    if (value->data) free( value->data ); /* already existing, free previous data */
    value->type  = type;
    value->len   = total_len;
    value->data  = ptr;
    touch_key( key );
    if (debug_level > 1) dump_operation( key, value, "Set" );
}

/* get a key value */
static void get_value( struct key *key, WCHAR *name, unsigned int offset,
                       unsigned int maxlen, int *type, int *len, void *data )
{
    struct key_value *value;
    int index;

    if ((value = find_value( key, name, &index )))
    {
        *type = value->type;
        *len  = value->len;
        if (value->data && offset < value->len)
        {
            if (maxlen > value->len - offset) maxlen = value->len - offset;
            memcpy( data, (char *)value->data + offset, maxlen );
        }
        if (debug_level > 1) dump_operation( key, value, "Get" );
    }
    else
    {
        *type = -1;
        set_error( STATUS_OBJECT_NAME_NOT_FOUND );
    }
}

/* enumerate a key value */
static void enum_value( struct key *key, int i, WCHAR *name, unsigned int offset,
                        unsigned int maxlen, int *type, int *len, void *data )
{
    struct key_value *value;

    if (i < 0 || i > key->last_value) set_error( STATUS_NO_MORE_ENTRIES );
    else
    {
        value = &key->values[i];
        strcpyW( name, value->name );
        *type = value->type;
        *len  = value->len;
        if (value->data && offset < value->len)
        {
            if (maxlen > value->len - offset) maxlen = value->len - offset;
            memcpy( data, (char *)value->data + offset, maxlen );
        }
        if (debug_level > 1) dump_operation( key, value, "Enum" );
    }
}

/* delete a value */
static void delete_value( struct key *key, const WCHAR *name )
{
    struct key_value *value;
    int i, index, nb_values;

    if (!(value = find_value( key, name, &index )))
    {
        set_error( STATUS_OBJECT_NAME_NOT_FOUND );
        return;
    }
    if (debug_level > 1) dump_operation( key, value, "Delete" );
    free( value->name );
    if (value->data) free( value->data );
    for (i = index; i < key->last_value; i++) key->values[i] = key->values[i + 1];
    key->last_value--;
    touch_key( key );

    /* try to shrink the array */
    nb_values = key->nb_values;
    if (nb_values > MIN_VALUES && key->last_value < nb_values / 2)
    {
        struct key_value *new_val;
        nb_values -= nb_values / 3;  /* shrink by 33% */
        if (nb_values < MIN_VALUES) nb_values = MIN_VALUES;
        if (!(new_val = realloc( key->values, nb_values * sizeof(*new_val) ))) return;
        key->values = new_val;
        key->nb_values = nb_values;
    }
}    

static struct key *get_hkey_obj( int hkey, unsigned int access );

static struct key *create_root_key( int hkey )
{
    int dummy;
    struct key *key;

    switch(hkey)
    {
    /* the two real root-keys */
    case HKEY_LOCAL_MACHINE:
        {
            static const WCHAR name[] = { 'M','A','C','H','I','N','E',0 };
            key = alloc_key( name, time(NULL) );
        }
        break;
    case HKEY_USERS:
        {
            static const WCHAR name[] = { 'U','S','E','R',0 };
            key = alloc_key( name, time(NULL) );
        }
        break;
    /* special subkeys */
    case HKEY_CLASSES_ROOT:
        {
            static const WCHAR name[] =
                          { 'S','O','F','T','W','A','R','E','\\','C','l','a','s','s','e','s',0 };

            struct key *root = get_hkey_obj( HKEY_LOCAL_MACHINE, 0 );
            assert( root );
            key = create_key( root, name, sizeof(name), NULL, 0, time(NULL), &dummy );
            release_object( root );
        }
        break;
    case HKEY_CURRENT_CONFIG:
        {
            static const WCHAR name[] = {
                'S','Y','S','T','E','M','\\',
                'C','U','R','R','E','N','T','C','O','N','T','R','O','L','S','E','T','\\',
                'H','A','R','D','W','A','R','E','P','R','O','F','I','L','E','S','\\',
                'C','U','R','R','E','N','T',0};
            struct key *root = get_hkey_obj( HKEY_LOCAL_MACHINE, 0 );
            assert( root );
            key = create_key( root, name, sizeof(name), NULL, 0, time(NULL), &dummy );
            release_object( root );
        }
        break;
    case HKEY_CURRENT_USER:
        {
            /* get the current user name */
            int i, len;
            WCHAR *name;
            char buffer[10];
            const char *p;
            struct passwd *pwd = getpwuid( getuid() );

            if (pwd) p = pwd->pw_name;
            else
            {
                sprintf( buffer, "%ld", (long) getuid() );
                p = buffer;
            }
            len = strlen(p);
            if ((name = mem_alloc( (len+1) * sizeof(WCHAR) )))
            {
                struct key *root = get_hkey_obj( HKEY_USERS, 0 );
                assert( root );
                for (i = 0; i <= len; i++) name[i] = p[i];
                key = create_key( root, name, (len+1) * sizeof(WCHAR),
                                  NULL, 0, time(NULL), &dummy );
                release_object( root );
                free( name );
            }
            else key = NULL;
        }
        break;
    /* dynamically generated keys */
    case HKEY_PERFORMANCE_DATA:
        {
            static const WCHAR name[] = { 'P','E','R','F','D','A','T','A',0 };  /* FIXME */
            key = alloc_key( name, time(NULL) );
        }
        break;
    case HKEY_DYN_DATA:
        {
            static const WCHAR name[] = { 'D','Y','N','D','A','T','A',0 };  /* FIXME */
            key = alloc_key( name, time(NULL) );
        }
        break;
    default:
        key = NULL;
        assert(0);
    }
    if (key)
    {
        root_keys[hkey - HKEY_ROOT_FIRST] = key;
        key->flags |= KEY_ROOT;
    }
    return key;
}

/* get the registry key corresponding to an hkey handle */
static struct key *get_hkey_obj( int hkey, unsigned int access )
{
    struct key *key;

    if (IS_ROOT_HKEY(hkey))
    {
        if (!(key = root_keys[hkey - HKEY_ROOT_FIRST])) key = create_root_key( hkey );
        grab_object( key );
    }
    else
        key = (struct key *)get_handle_obj( current->process, hkey, access, &key_ops );
    return key;
}

/* read a line from the input file */
static int read_next_line( struct file_load_info *info )
{
    char *newbuf;
    int newlen, pos = 0;

    info->line++;
    for (;;)
    {
        if (!fgets( info->buffer + pos, info->len - pos, info->file ))
            return (pos != 0);  /* EOF */
        pos = strlen(info->buffer);
        if (info->buffer[pos-1] == '\n')
        {
            /* got a full line */
            info->buffer[--pos] = 0;
            if (pos > 0 && info->buffer[pos-1] == '\r') info->buffer[pos-1] = 0;
            return 1;
        }
        if (pos < info->len - 1) return 1;  /* EOF but something was read */

        /* need to enlarge the buffer */
        newlen = info->len + info->len / 2;
        if (!(newbuf = realloc( info->buffer, newlen )))
        {
            set_error( STATUS_NO_MEMORY );
            return -1;
        }
        info->buffer = newbuf;
        info->len = newlen;
    }
}

/* make sure the temp buffer holds enough space */
static int get_file_tmp_space( struct file_load_info *info, int size )
{
    char *tmp;
    if (info->tmplen >= size) return 1;
    if (!(tmp = realloc( info->tmp, size )))
    {
        set_error( STATUS_NO_MEMORY );
        return 0;
    }
    info->tmp = tmp;
    info->tmplen = size;
    return 1;
}

/* report an error while loading an input file */
static void file_read_error( const char *err, struct file_load_info *info )
{
    fprintf( stderr, "Line %d: %s '%s'\n", info->line, err, info->buffer );
}

/* parse an escaped string back into Unicode */
/* return the number of chars read from the input, or -1 on output overflow */
static int parse_strW( WCHAR *dest, int *len, const char *src, char endchar )
{
    int count = sizeof(WCHAR);  /* for terminating null */
    const char *p = src;
    while (*p && *p != endchar)
    {
        if (*p != '\\') *dest = (WCHAR)*p++;
        else
        {
            p++;
            switch(*p)
            {
            case 'a': *dest = '\a'; p++; break;
            case 'b': *dest = '\b'; p++; break;
            case 'e': *dest = '\e'; p++; break;
            case 'f': *dest = '\f'; p++; break;
            case 'n': *dest = '\n'; p++; break;
            case 'r': *dest = '\r'; p++; break;
            case 't': *dest = '\t'; p++; break;
            case 'v': *dest = '\v'; p++; break;
            case 'x':  /* hex escape */
                p++;
                if (!isxdigit(*p)) *dest = 'x';
                else
                {
                    *dest = to_hex(*p++);
                    if (isxdigit(*p)) *dest = (*dest * 16) + to_hex(*p++);
                    if (isxdigit(*p)) *dest = (*dest * 16) + to_hex(*p++);
                    if (isxdigit(*p)) *dest = (*dest * 16) + to_hex(*p++);
                }
                break;
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':  /* octal escape */
                *dest = *p++ - '0';
                if (*p >= '0' && *p <= '7') *dest = (*dest * 8) + (*p++ - '0');
                if (*p >= '0' && *p <= '7') *dest = (*dest * 8) + (*p++ - '0');
                break;
            default:
                *dest = (WCHAR)*p++;
                break;
            }
        }
        if ((count += sizeof(WCHAR)) > *len) return -1;  /* dest buffer overflow */
        dest++;
    }
    *dest = 0;
    if (!*p) return -1;  /* delimiter not found */
    *len = count;
    return p + 1 - src;
}

/* convert a data type tag to a value type */
static int get_data_type( const char *buffer, int *type, int *parse_type )
{
    struct data_type { const char *tag; int len; int type; int parse_type; };

    static const struct data_type data_types[] = 
    {                   /* actual type */  /* type to assume for parsing */
        { "\"",        1,   REG_SZ,              REG_SZ },
        { "str:\"",    5,   REG_SZ,              REG_SZ },
        { "str(2):\"", 8,   REG_EXPAND_SZ,       REG_SZ },
        { "str(7):\"", 8,   REG_MULTI_SZ,        REG_SZ },
        { "hex:",      4,   REG_BINARY,          REG_BINARY },
        { "dword:",    6,   REG_DWORD,           REG_DWORD },
        { "hex(",      4,   -1,                  REG_BINARY },
        { NULL, }
    };

    const struct data_type *ptr;
    char *end;

    for (ptr = data_types; ptr->tag; ptr++)
    {
        if (memcmp( ptr->tag, buffer, ptr->len )) continue;
        *parse_type = ptr->parse_type;
        if ((*type = ptr->type) != -1) return ptr->len;
        /* "hex(xx):" is special */
        *type = (int)strtoul( buffer + 4, &end, 16 );
        if ((end <= buffer) || memcmp( end, "):", 2 )) return 0;
        return end + 2 - buffer;
    }
    return 0;
}

/* load and create a key from the input file */
static struct key *load_key( struct key *base, const char *buffer, unsigned int options,
                             int prefix_len, struct file_load_info *info )
{
    WCHAR *p;
    int res, len, modif;

    len = strlen(buffer) * sizeof(WCHAR);
    if (!get_file_tmp_space( info, len )) return NULL;

    if ((res = parse_strW( (WCHAR *)info->tmp, &len, buffer, ']' )) == -1)
    {
        file_read_error( "Malformed key", info );
        return NULL;
    }
    if (!sscanf( buffer + res, " %d", &modif )) modif = time(NULL);

    p = (WCHAR *)info->tmp;
    while (prefix_len && *p) { if (*p++ == '\\') prefix_len--; }

    if (!*p)
    {
        if (prefix_len > 1)
        {
            file_read_error( "Malformed key", info );
            return NULL;
        }
        /* empty key name, return base key */
        return (struct key *)grab_object( base );
    }
    return create_key( base, p, len - ((char *)p - info->tmp), NULL, options, modif, &res );
}

/* parse a comma-separated list of hex digits */
static int parse_hex( unsigned char *dest, int *len, const char *buffer )
{
    const char *p = buffer;
    int count = 0;
    while (isxdigit(*p))
    {
        int val;
        char buf[3];
        memcpy( buf, p, 2 );
        buf[2] = 0;
        sscanf( buf, "%x", &val );
        if (count++ >= *len) return -1;  /* dest buffer overflow */
        *dest++ = (unsigned char )val;
        p += 2;
        if (*p == ',') p++;
    }
    *len = count;
    return p - buffer;
}

/* parse a value name and create the corresponding value */
static struct key_value *parse_value_name( struct key *key, const char *buffer, int *len,
                                           struct file_load_info *info )
{
    int maxlen = strlen(buffer) * sizeof(WCHAR);
    if (!get_file_tmp_space( info, maxlen )) return NULL;
    if (buffer[0] == '@')
    {
        info->tmp[0] = info->tmp[1] = 0;
        *len = 1;
    }
    else
    {
        if ((*len = parse_strW( (WCHAR *)info->tmp, &maxlen, buffer + 1, '\"' )) == -1) goto error;
        (*len)++;  /* for initial quote */
    }
    if (buffer[*len] != '=') goto error;
    (*len)++;
    return insert_value( key, (WCHAR *)info->tmp );

 error:
    file_read_error( "Malformed value name", info );
    return NULL;
}

/* load a value from the input file */
static int load_value( struct key *key, const char *buffer, struct file_load_info *info )
{
    DWORD dw;
    void *ptr, *newptr;
    int maxlen, len, res;
    int type, parse_type;
    struct key_value *value;

    if (!(value = parse_value_name( key, buffer, &len, info ))) return 0;
    if (!(res = get_data_type( buffer + len, &type, &parse_type ))) goto error;
    buffer += len + res;

    switch(parse_type)
    {
    case REG_SZ:
        len = strlen(buffer) * sizeof(WCHAR);
        if (!get_file_tmp_space( info, len )) return 0;
        if ((res = parse_strW( (WCHAR *)info->tmp, &len, buffer, '\"' )) == -1) goto error;
        ptr = info->tmp;
        break;
    case REG_DWORD:
        dw = strtoul( buffer, NULL, 16 );
        ptr = &dw;
        len = sizeof(dw);
        break;
    case REG_BINARY:  /* hex digits */
        len = 0;
        for (;;)
        {
            maxlen = 1 + strlen(buffer)/3;  /* 3 chars for one hex byte */
            if (!get_file_tmp_space( info, len + maxlen )) return 0;
            if ((res = parse_hex( info->tmp + len, &maxlen, buffer )) == -1) goto error;
            len += maxlen;
            buffer += res;
            while (isspace(*buffer)) buffer++;
            if (!*buffer) break;
            if (*buffer != '\\') goto error;
            if (read_next_line( info) != 1) goto error;
            buffer = info->buffer;
            while (isspace(*buffer)) buffer++;
        }
        ptr = info->tmp;
        break;
    default:
        assert(0);
        ptr = NULL;  /* keep compiler quiet */
        break;
    }

    if (!len) newptr = NULL;
    else if (!(newptr = memdup( ptr, len ))) return 0;

    if (value->data) free( value->data );
    value->data = newptr;
    value->len  = len;
    value->type = type;
    /* update the key level but not the modification time */
    key->level = max( key->level, current_level );
    return 1;

 error:
    file_read_error( "Malformed value", info );
    return 0;
}

/* return the length (in path elements) of name that is part of the key name */
/* for instance if key is USER\foo\bar and name is foo\bar\baz, return 2 */
static int get_prefix_len( struct key *key, const char *name, struct file_load_info *info )
{
    WCHAR *p;
    int res;
    int len = strlen(name) * sizeof(WCHAR);
    if (!get_file_tmp_space( info, len )) return 0;

    if ((res = parse_strW( (WCHAR *)info->tmp, &len, name, ']' )) == -1)
    {
        file_read_error( "Malformed key", info );
        return 0;
    }
    for (p = (WCHAR *)info->tmp; *p; p++) if (*p == '\\') break;
    *p = 0;
    for (res = 1; key; res++)
    {
        if (!strcmpiW( (WCHAR *)info->tmp, key->name )) break;
        key = key->parent;
    }
    if (!key) res = 0;  /* no matching name */
    return res;
}

/* load all the keys from the input file */
static void load_keys( struct key *key, FILE *f )
{
    struct key *subkey = NULL;
    struct file_load_info info;
    char *p;
    unsigned int options = 0;
    int prefix_len = -1;  /* number of key name prefixes to skip */

    if (key->flags & KEY_VOLATILE) options |= REG_OPTION_VOLATILE;

    info.file   = f;
    info.len    = 4;
    info.tmplen = 4;
    info.line   = 0;
    if (!(info.buffer = mem_alloc( info.len ))) return;
    if (!(info.tmp = mem_alloc( info.tmplen )))
    {
        free( info.buffer );
        return;
    }

    if ((read_next_line( &info ) != 1) ||
        strcmp( info.buffer, "WINE REGISTRY Version 2" ))
    {
        set_error( STATUS_NOT_REGISTRY_FILE );
        goto done;
    }

    while (read_next_line( &info ) == 1)
    {
        for (p = info.buffer; *p && isspace(*p); p++);
        switch(*p)
        {
        case '[':   /* new key */
            if (subkey) release_object( subkey );
            if (prefix_len == -1) prefix_len = get_prefix_len( key, p + 1, &info );
            if (!(subkey = load_key( key, p + 1, options, prefix_len, &info )))
                file_read_error( "Error creating key", &info );
            break;
        case '@':   /* default value */
        case '\"':  /* value */
            if (subkey) load_value( subkey, p, &info );
            else file_read_error( "Value without key", &info );
            break;
        case '#':   /* comment */
        case ';':   /* comment */
        case 0:     /* empty line */
            break;
        default:
            file_read_error( "Unrecognized input", &info );
            break;
        }
    }

 done:
    if (subkey) release_object( subkey );
    free( info.buffer );
    free( info.tmp );
}

/* load a part of the registry from a file */
static void load_registry( struct key *key, int handle )
{
    struct object *obj;
    int fd;

    if (!(obj = get_handle_obj( current->process, handle, GENERIC_READ, NULL ))) return;
    fd = obj->ops->get_read_fd( obj );
    release_object( obj );
    if (fd != -1)
    {
        FILE *f = fdopen( fd, "r" );
        if (f)
        {
            load_keys( key, f );
            fclose( f );
        }
        else file_set_error();
    }
}

/* update the level of the parents of a key (only needed for the old format) */
static int update_level( struct key *key )
{
    int i;
    int max = key->level;
    for (i = 0; i <= key->last_subkey; i++)
    {
        int sub = update_level( key->subkeys[i] );
        if (sub > max) max = sub;
    }
    key->level = max;
    return max;
}

/* save a registry branch to a file */
static void save_all_subkeys( struct key *key, FILE *f )
{
    fprintf( f, "WINE REGISTRY Version 2\n" );
    fprintf( f, ";; All keys relative to " );
    dump_path( key, NULL, f );
    fprintf( f, "\n" );
    save_subkeys( key, key, f );
}

/* save a registry branch to a file handle */
static void save_registry( struct key *key, int handle )
{
    struct object *obj;
    int fd;

    if (key->flags & KEY_DELETED)
    {
        set_error( STATUS_KEY_DELETED );
        return;
    }
    if (!(obj = get_handle_obj( current->process, handle, GENERIC_WRITE, NULL ))) return;
    fd = obj->ops->get_write_fd( obj );
    release_object( obj );
    if (fd != -1)
    {
        FILE *f = fdopen( fd, "w" );
        if (f)
        {
            save_all_subkeys( key, f );
            if (fclose( f )) file_set_error();
        }
        else
        {
            file_set_error();
            close( fd );
        }
    }
}

/* register a key branch for being saved on exit */
static void register_branch_for_saving( struct key *key, const char *path, size_t len )
{
    if (save_branch_count >= MAX_SAVE_BRANCH_INFO)
    {
        set_error( STATUS_NO_MORE_ENTRIES );
        return;
    }
    if (!(save_branch_info[save_branch_count].path = memdup( path, len+1 ))) return;
    save_branch_info[save_branch_count].path[len] = 0;
    save_branch_info[save_branch_count].key = (struct key *)grab_object( key );
    save_branch_count++;
}

/* save a registry branch to a file */
static int save_branch( struct key *key, const char *path )
{
    char *p, *real, *tmp = NULL;
    int fd, count = 0, ret = 0;
    FILE *f;

    /* get the real path */

    if (!(real = malloc( PATH_MAX ))) return 0;
    if (!realpath( path, real ))
    {
        free( real );
        real = NULL;
    }
    else path = real;

    /* test the file type */

    if ((fd = open( path, O_WRONLY )) != -1)
    {
        struct stat st;
        /* if file is not a regular file or has multiple links,
           write directly into it; otherwise use a temp file */
        if (!fstat( fd, &st ) && (!S_ISREG(st.st_mode) || st.st_nlink > 1))
        {
            ftruncate( fd, 0 );
            goto save;
        }
        close( fd );
    }

    /* create a temp file in the same directory */

    if (!(tmp = malloc( strlen(path) + 20 ))) goto done;
    strcpy( tmp, path );
    if ((p = strrchr( tmp, '/' ))) p++;
    else p = tmp;
    for (;;)
    {
        sprintf( p, "reg%lx%04x.tmp", (long) getpid(), count++ );
        if ((fd = open( tmp, O_CREAT | O_EXCL | O_WRONLY, 0666 )) != -1) break;
        if (errno != EEXIST) goto done;
        close( fd );
    }

    /* now save to it */

 save:
    if (!(f = fdopen( fd, "w" )))
    {
        if (tmp) unlink( tmp );
        close( fd );
        goto done;
    }

    if (debug_level > 1)
    {
        fprintf( stderr, "%s: ", path );
        dump_operation( key, NULL, "saving" );
    }

    save_all_subkeys( key, f );
    ret = !fclose(f);

    if (tmp)
    {
        /* if successfully written, rename to final name */
        if (ret) ret = !rename( tmp, path );
        if (!ret) unlink( tmp );
        free( tmp );
    }

done:
    if (real) free( real );
    return ret;
}

/* periodic saving of the registry */
static void periodic_save( void *arg )
{
    int i;
    for (i = 0; i < save_branch_count; i++)
        save_branch( save_branch_info[i].key, save_branch_info[i].path );
    add_timeout( &next_save_time, save_period );
    save_timeout_user = add_timeout_user( &next_save_time, periodic_save, 0 );
}

/* save the registry and close the top-level keys; used on server exit */
void close_registry(void)
{
    int i;

    for (i = 0; i < save_branch_count; i++)
    {
        if (!save_branch( save_branch_info[i].key, save_branch_info[i].path ))
        {
            fprintf( stderr, "wineserver: could not save registry branch to %s",
                     save_branch_info[i].path );
            perror( " " );
        }
        release_object( save_branch_info[i].key );
    }
    for (i = 0; i < NB_ROOT_KEYS; i++)
    {
        if (root_keys[i]) release_object( root_keys[i] );
    }
}


/* create a registry key */
DECL_HANDLER(create_key)
{
    struct key *key, *parent;
    WCHAR *class;
    unsigned int access = req->access;

    if (access & MAXIMUM_ALLOWED) access = KEY_ALL_ACCESS;  /* FIXME: needs general solution */
    req->hkey = -1;
    if ((parent = get_hkey_obj( req->parent, 0 /*FIXME*/ )))
    {
        if ((class = req_strdupW( req, req->class )))
        {
            if ((key = create_key( parent, req->name, sizeof(req->name), class, req->options,
                                   req->modif, &req->created )))
            {
                req->hkey = alloc_handle( current->process, key, access, 0 );
                release_object( key );
            }
            free( class );
        }
        release_object( parent );
    }
}

/* open a registry key */
DECL_HANDLER(open_key)
{
    struct key *key, *parent;
    unsigned int access = req->access;

    if (access & MAXIMUM_ALLOWED) access = KEY_ALL_ACCESS;  /* FIXME: needs general solution */
    req->hkey = -1;
    if ((parent = get_hkey_obj( req->parent, 0 /*FIXME*/ )))
    {
        if ((key = open_key( parent, req->name, sizeof(req->name) )))
        {
            req->hkey = alloc_handle( current->process, key, access, 0 );
            release_object( key );
        }
        release_object( parent );
    }
}

/* delete a registry key */
DECL_HANDLER(delete_key)
{
    struct key *key;

    if ((key = get_hkey_obj( req->hkey, 0 /*FIXME*/ )))
    {
        delete_key( key, req->name, sizeof(req->name) );
        release_object( key );
    }
}

/* close a registry key */
DECL_HANDLER(close_key)
{
    int hkey = req->hkey;
    /* ignore attempts to close a root key */
    if (!IS_ROOT_HKEY(hkey)) close_handle( current->process, hkey );
}

/* enumerate registry subkeys */
DECL_HANDLER(enum_key)
{
    struct key *key;

    req->name[0] = req->class[0] = 0;
    if ((key = get_hkey_obj( req->hkey, KEY_ENUMERATE_SUB_KEYS )))
    {
        enum_key( key, req->index, req->name, req->class, &req->modif );
        release_object( key );
    }
}

/* query information about a registry key */
DECL_HANDLER(query_key_info)
{
    struct key *key;

    req->name[0] = req->class[0] = 0;
    if ((key = get_hkey_obj( req->hkey, KEY_QUERY_VALUE )))
    {
        query_key( key, req );
        release_object( key );
    }
}

/* set a value of a registry key */
DECL_HANDLER(set_key_value)
{
    struct key *key;
    unsigned int max = get_req_size( req, req->data, sizeof(req->data[0]) );
    unsigned int datalen = req->len;

    if (datalen > max) datalen = max;
    if ((key = get_hkey_obj( req->hkey, KEY_SET_VALUE )))
    {
        set_value( key, copy_path( req->name ), req->type, req->total,
                   req->offset, datalen, req->data );
        release_object( key );
    }
}

/* retrieve the value of a registry key */
DECL_HANDLER(get_key_value)
{
    struct key *key;
    unsigned int max = get_req_size( req, req->data, sizeof(req->data[0]) );

    req->len = 0;
    if ((key = get_hkey_obj( req->hkey, KEY_QUERY_VALUE )))
    {
        get_value( key, copy_path( req->name ), req->offset, max,
                   &req->type, &req->len, req->data );
        release_object( key );
    }
}

/* enumerate the value of a registry key */
DECL_HANDLER(enum_key_value)
{
    struct key *key;
    unsigned int max = get_req_size( req, req->data, sizeof(req->data[0]) );

    req->len = 0;
    req->name[0] = 0;
    if ((key = get_hkey_obj( req->hkey, KEY_QUERY_VALUE )))
    {
        enum_value( key, req->index, req->name, req->offset, max,
                    &req->type, &req->len, req->data );
        release_object( key );
    }
}

/* delete a value of a registry key */
DECL_HANDLER(delete_key_value)
{
    WCHAR *name;
    struct key *key;

    if ((key = get_hkey_obj( req->hkey, KEY_SET_VALUE )))
    {
        if ((name = req_strdupW( req, req->name )))
        {
            delete_value( key, name );
            free( name );
        }
        release_object( key );
    }
}

/* load a registry branch from a file */
DECL_HANDLER(load_registry)
{
    struct key *key;

    if ((key = get_hkey_obj( req->hkey, KEY_SET_VALUE | KEY_CREATE_SUB_KEY )))
    {
        /* FIXME: use subkey name */
        load_registry( key, req->file );
        release_object( key );
    }
}

/* save a registry branch to a file */
DECL_HANDLER(save_registry)
{
    struct key *key;

    if ((key = get_hkey_obj( req->hkey, KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS )))
    {
        save_registry( key, req->file );
        release_object( key );
    }
}

/* set the current and saving level for the registry */
DECL_HANDLER(set_registry_levels)
{
    current_level  = req->current;
    saving_level   = req->saving;

    /* set periodic save timer */

    if (save_timeout_user)
    {
        remove_timeout_user( save_timeout_user );
        save_timeout_user = NULL;
    }
    if ((save_period = req->period))
    {
        if (save_period < 10000) save_period = 10000;  /* limit rate */
        gettimeofday( &next_save_time, 0 );
        add_timeout( &next_save_time, save_period );
        save_timeout_user = add_timeout_user( &next_save_time, periodic_save, 0 );
    }
}

/* save a registry branch at server exit */
DECL_HANDLER(save_registry_atexit)
{
    struct key *key;

    if ((key = get_hkey_obj( req->hkey, KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS )))
    {
        register_branch_for_saving( key, req->file, get_req_strlen( req, req->file ) );
        release_object( key );
    }
}