Source File modules/rx/rx_tree.c

    1    | /***************************************
    2    |   $Revision: 1.11 $
    3    |
    4    |   Radix tree (rx).  rx_tree.c - functions to operate on trees
    5    |   (creation/deletion/finding).
    6    |
    7    |   Status: NOT REVUED, TESTED, INCOMPLETE
    8    |
    9    |   Design and implementation by: Marek Bukowy
    10   |
    11   |   ******************/ /******************
    12   |   Copyright (c) 1999                              RIPE NCC
    13   |
    14   |   All Rights Reserved
    15   |
    16   |   Permission to use, copy, modify, and distribute this software and its
    17   |   documentation for any purpose and without fee is hereby granted,
    18   |   provided that the above copyright notice appear in all copies and that
    19   |   both that copyright notice and this permission notice appear in
    20   |   supporting documentation, and that the name of the author not be
    21   |   used in advertising or publicity pertaining to distribution of the
    22   |   software without specific, written prior permission.
    23   |
    24   |   THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
    25   |   ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL
    26   |   AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
    27   |   DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
    28   |   AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    29   |   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
    30   |   ***************************************/
    31   |
    32   | #include <erroutines.h>
    33   | #include <iproutines.h>
    34   | #include <memwrap.h>
    35   | #include <stubs.h>
    36   |
    37   | /***************************************************************************/
    38   |
    39   | #define RX_IMPL
    40   |
    41   | #include <rxroutines.h>
    42   | /***************************************************************************/
    43   |
    44   |
    45   | /*+++++++++
    46   |   go down the tree calling func on every node.
    47   |   (func takes the node pointer and the current level)
    48   |
    49   |   the function is called recursively with level increased
    50   |   it stops recursing when no child nodes are found or maxlevel is reached.
    51   |
    52   |   therefore the initial call must set level to 0.
    53   |
    54   |   the nodecounter increments at every node, and is the return value
    55   |   of the function. So start with 0 to get the number of nodes traversed.
    56   |
    57   |   ERROR HANDLING IS DIFFERENT HERE!
    58   |   Unlike other functions it is not the return value:
    59   |   The error code from the func function IF DEFINED (== not NULL ) goes
    60   |   to the variable pointed to by the last parameter.
    61   | ++++++++++++*/
    62   | int
    63   | rx_walk_tree(rx_node_t *node,
    64   | 	     er_ret_t (*func)(rx_node_t *node, int level, int nodecounter,
    65   | 			  void *userptr),
    66   | 	     rx_walk_mt walk_mode,
    67   | 	                     // controls if glue nodes are counted
    68   | 	                     // and if levels or prefix lenghts are checked
    69   | 	     int maxlevel,
    70   | 	     int level,
    71   | 	     int nodecounter,
    72   | 	     void *userptr,
    73   | 	     er_ret_t *err)
    74   | {
    75   | int i, link, skpglue=0;
    76   |
    77   |  if( node == NULL ) die; // program error. we expect a valid, checked, node.
    78   |
    79   |  // count the node appropriately:
    80   |  // if (not glue) or (it doesn't matter)
    81   |
    82   |  if( node->glue == 0 || (walk_mode & RX_WALK_SKPGLU) == 0 ) {
    83   |    level++;
    84   |  } else { /* nodeglue = 1 && walkmode&skpglue = 1 */
    85   |    skpglue = 1;
    86   |  }
    87   |
    88   |  // check the limits and maybe quit here: prefix length for RX_WALK_PRFLEN,
    89   |  // level otherwise
    90   |
    91   |  if(walk_mode & RX_WALK_PRFLEN) {
    92   |    if(node->prefix.bits > maxlevel) {
    93   |      return nodecounter;
    94   |    }
    95   |  }
    96   |  else if( level > maxlevel ) {
    97   |    return nodecounter;
    98   |  }
    99   |
    100  |  // didn't quit ?? OK, count it too...
    101  |  if( skpglue == 0 ) {
    102  |    nodecounter++;
    103  |  }
    104  |
    105  |  if( func != NULL && skpglue == 0 ) {
    106  |    *err = func(node, level, nodecounter, userptr);
    107  |
    108  |    // abort the walk on error
    109  |    if( *err != RX_OK ) {
    110  |      ER_dbg_va(FAC_RX, ASP_RX_TREE_WALK,
    111  | 	       "walk_tree: func returned error %d, aborting", *err);
    112  |      return nodecounter;
    113  |    }
    114  |  }
    115  |
    116  |
    117  |  for(i=0; i<=1; i++) {
    118  |
    119  |    // reverse the sense of the walk
    120  |    link = ( walk_mode & RX_WALK_REVERS ) ? ! i : i;
    121  |
    122  |    if( node->child_ptr[link] != NULL ) {
    123  |      nodecounter += rx_walk_tree(node->child_ptr[link], func, walk_mode,
    124  | 				 maxlevel, level, 0, userptr, err);
    125  |      // abort the walk on error
    126  |      if( func != NULL && *err != RX_OK ) {
    127  |        break;
    128  |      }
    129  |    }
    130  |  }
    131  |
    132  |  return nodecounter;
    133  | }
    134  |
    135  |
    136  |
    137  |
    138  | /***************************************************************************/
    139  | /*++++++++++++++
    140  |   finds a tree matching the specified criteria(registry+space+family).
    141  |
    142  |   MT-note: locks/unlocks forest (still to be done)
    143  |
    144  |   Returns: RX_OK or RX_NOTREE if no such tree can be found.
    145  | +++++++++++*/
    146  |
    147  | er_ret_t
    148  | RX_get_tree ( rx_tree_t **treeptr, /*+ answer goes here, please +*/
    149  | 	      rx_regid_t reg_id,   /*+ id of the registry +*/
    150  | 	      ip_space_t spc_id,   /*+ type of space (ipv4/ipv6) +*/
    151  | 	      rx_fam_t   fam_id    /*+ family of objects (route/inetnum) +*/
    152  | 	      )
    153  |
    154  | {
    155  |   GList *elem = g_list_first(rx_forest);
    156  |   rx_tree_t *trp;
    157  |
    158  |   while( elem != NULL ) {
    159  |     trp = (rx_tree_t *) elem->data;
    160  |
    161  |     if( trp->reg_id == reg_id
    162  | 	&&   trp->space == spc_id  && trp->family == fam_id) {
    163  |       /* copy the value to user's data */
    164  |       *treeptr = trp;
    165  |       ER_dbg_va(FAC_RX, ASP_RX_TREE_BOT, "tree found at %08x",trp);
    166  |
    167  |       return RX_OK;
    168  |     }
    169  |     elem = g_list_next(elem);
    170  |   }
    171  |
    172  |   *treeptr = NULL; // set no NOT FOUND
    173  |   return RX_NOTREE;
    174  | }
    175  |
    176  |
    177  | /***************************************************************************/
    178  | /*++++++
    179  |   creates a (top) tree for the space, fills out sql table of trees
    180  |   generates a tablename for a tree (if NONE)
    181  |   updates LL of trees
    182  |
    183  |   MT-note: locks/unlocks the forest (still to be done)
    184  |
    185  | ++++++++*/
    186  | er_ret_t
    187  | RX_tree_cre (
    188  | 	      rx_regid_t reg_id,    /*+ id of the registry +*/
    189  | 	      ip_space_t spc_id,    /*+ space id, one of IPv4 IPv6. +*/
    190  | 	      rx_fam_t   fam_id,    /*+ family of objects (route/inetnum) +*/
    191  | 	      char      *prefixstr, /*+ prefix the tree will cover (string) +*/
    192  | 	      rx_mem_mt   mem_mode, /* memory only, memory+sql, sql only +*/
    193  | 	      rx_subtree_mt subtrees,	/*+ one of NONE, AUTO, HAND +*/
    194  | 	      rx_tree_t **treestore /* store the tree pointer here */
    195  | 	     )
    196  |
    197  | {
    198  |   er_ret_t err;
    199  |   rx_tree_t *newtree;
    200  |   ip_prefix_t    newpref;
    201  |
    202  |   if( IP_pref_e2b(&newpref, prefixstr) != IP_OK ) {
    203  |     die;
    204  |   }
    205  |
    206  |   RX_get_tree ( &newtree, reg_id, spc_id, fam_id);
    207  |
    208  |   if ( newtree != NULL ) {
    209  |     // die; /*  error RX_TRALEX == tree already exists */
    210  |     return RX_TRALEX;
    211  |   }
    212  |
    213  |
    214  |   if ( (err=wr_malloc( (void **) & newtree, sizeof(rx_tree_t))) != UT_OK ) {
    215  |     return err;  // die
    216  |   }
    217  |
    218  |   ER_dbg_va(FAC_RX, ASP_RX_TREE_BOT, "creating a tree at %08x", newtree);
    219  |
    220  |   /* copy tree settings */
    221  |
    222  |   newtree -> reg_id = reg_id;
    223  |   newtree -> space  = spc_id;
    224  |   newtree -> family = fam_id;
    225  |   newtree -> subtrees = subtrees;
    226  |   newtree -> mem_mode = mem_mode;
    227  |
    228  |   /* set other tree values */
    229  |
    230  |   /* parent set to NULL because it's not a subtree */
    231  |   newtree -> parent_tree = NULL;
    232  |   // PR_zeroprefix(& newtree -> prefix);
    233  |   newtree -> maxbits = IP_sizebits(spc_id);
    234  |
    235  |   strcpy(newtree->data_table.val,"");
    236  |   strcpy(newtree->radix_table.val,"");
    237  |   strcpy(newtree->leaves_table.val,"");
    238  |
    239  |   newtree->num_nodes = 0;
    240  |
    241  |   newtree->top_ptr = NULL;
    242  |   newtree->top_key = SQ_NOKEY;
    243  |
    244  |   newtree->prefix = newpref;
    245  |
    246  |   TH_init_read_write_lock( &(newtree->rwlock));
    247  |
    248  |   *treestore = newtree;
    249  |
    250  |   return RX_OK;
    251  | }
    252  |
    253  | void RX_attach2forest(rx_tree_t *newtree) {
    254  |   /* put into LL of trees; handle alloc err ??? */
    255  |   /* if threads are supposed to be reading already,
    256  |      set forest mutex;  */
    257  |
    258  |   rx_forest = g_list_append (rx_forest, newtree);
    259  |
    260  |   /*  release forest mutex; */
    261  |
    262  | }