udevdb.c

   1 /*
   2  * udevdb.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   7  * Copyright (C) 2003 IBM Corp.
   8  *
   9  *      This program is free software; you can redistribute it and/or modify it
  10  *      under the terms of the GNU General Public License as published by the
  11  *      Free Software Foundation version 2 of the License.
  12  *
  13  *      This program is distributed in the hope that it will be useful, but
  14  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *      General Public License for more details.
  17  *
  18  *      You should have received a copy of the GNU General Public License along
  19  *      with this program; if not, write to the Free Software Foundation, Inc.,
  20  *      675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 /*
  25  * udev database library
  26  */
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <fcntl.h>
  30 #include <string.h>
  31 #include <sys/stat.h>
  32 #include <errno.h>
  33 #include <signal.h>
  34
  35 #include "udev_version.h"
  36 #include "udev.h"
  37 #include "namedev.h"
  38 #include "udevdb.h"
  39 #include "tdb/tdb.h"
  40 #include "libsysfs/libsysfs.h"
  41
  42 static TDB_CONTEXT *udevdb;
  43
  44
  45 int udevdb_add_dev(const char *path, const struct udevice *dev)
  46 {
  47         TDB_DATA key, data;
  48         char keystr[SYSFS_PATH_MAX];
  49
  50         if ((path == NULL) || (dev == NULL))
  51                 return -ENODEV;
  52
  53         memset(keystr, 0, NAME_SIZE);
  54         strcpy(keystr, path);
  55         key.dptr = keystr;
  56         key.dsize = strlen(keystr) + 1;
  57
  58         data.dptr = (void *)dev;
  59         data.dsize = sizeof(*dev);
  60
  61         return tdb_store(udevdb, key, data, TDB_REPLACE);
  62 }
  63
  64 struct udevice *udevdb_get_dev(const char *path)
  65 {
  66         TDB_DATA key, data;
  67         struct udevice *dev;
  68
  69         if (path == NULL)
  70                 return NULL;
  71
  72         key.dptr = (void *)path;
  73         key.dsize = strlen(path) + 1;
  74
  75         data = tdb_fetch(udevdb, key);
  76         if (data.dptr == NULL || data.dsize == 0)
  77                 return NULL;
  78
  79         dev = malloc(sizeof(*dev));
  80         if (dev == NULL)
  81                 goto exit;
  82
  83         memcpy(dev, data.dptr, sizeof(*dev));
  84 exit:
  85         free(data.dptr);
  86         return dev;
  87 }
  88
  89 int udevdb_delete_dev(const char *path)
  90 {
  91         TDB_DATA key;
  92         char keystr[SYSFS_PATH_MAX];
  93
  94         if (path == NULL)
  95                 return -EINVAL;
  96
  97         memset(keystr, 0, sizeof(keystr));
  98         strcpy(keystr, path);
  99
 100         key.dptr = keystr;
 101         key.dsize = strlen(keystr) + 1;
 102
 103         return tdb_delete(udevdb, key);
 104 }
 105
 106 /**
 107  * udevdb_exit: closes database
 108  */
 109 void udevdb_exit(void)
 110 {
 111         if (udevdb != NULL) {
 112                 tdb_close(udevdb);
 113                 udevdb = NULL;
 114         }
 115 }
 116
 117 /**
 118  * udevdb_init: initializes database
 119  * @init_flag: UDEVDB_INTERNAL - database stays in memory
 120  *             UDEVDB_DEFAULT - database is written to a file
 121  */
 122 int udevdb_init(int init_flag)
 123 {
 124         if (init_flag != UDEVDB_DEFAULT && init_flag != UDEVDB_INTERNAL)
 125                 return -EINVAL;
 126
 127         udevdb = tdb_open(udev_db_filename, 0, init_flag, O_RDWR | O_CREAT, 0644);
 128         if (udevdb == NULL) {
 129                 if (init_flag == UDEVDB_INTERNAL)
 130                         dbg("unable to initialize in-memory database");
 131                 else
 132                         dbg("unable to initialize database at '%s'", udev_db_filename);
 133                 return -EINVAL;
 134         }
 135         return 0;
 136 }