lib/ldb/examples/ldbreader.c

   1 /*
   2    example code for the ldb database library
   3
   4    Copyright (C) Brad Hards (bradh@frogmouth.net) 2005-2006
   5
   6      ** NOTE! The following LGPL license applies to the ldb
   7      ** library. This does NOT imply that all of Samba is released
   8      ** under the LGPL
   9
  10    This library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 3 of the License, or (at your option) any later version.
  14
  15    This library is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 /** \example ldbreader.c
  25
  26 The code below shows a simple LDB application.
  27
  28 It lists / dumps the records in a LDB database to standard output.
  29
  30 */
  31
  32 #include "ldb.h"
  33
  34 /*
  35   ldb_ldif_write takes a function pointer to a custom output
  36   function. This version is about as simple as the output function can
  37   be. In a more complex example, you'd likely be doing something with
  38   the private data function (e.g. holding a file handle).
  39 */
  40 static int vprintf_fn(void *private_data, const char *fmt, ...)
  41 {
  42         int retval;
  43         va_list ap;
  44
  45         va_start(ap, fmt);
  46         /* We just write to standard output */
  47         retval = vprintf(fmt, ap);
  48         va_end(ap);
  49         /* Note that the function should return the number of
  50            bytes written, or a negative error code */
  51         return retval;
  52 }
  53
  54 int main(int argc, const char **argv)
  55 {
  56         struct ldb_context *ldb;
  57         const char *expression = "(dn=*)";
  58         struct ldb_result *resultMsg;
  59         int i;
  60
  61         /*
  62           This is the always the first thing you want to do in an LDB
  63           application - initialise up the context structure.
  64
  65           Note that you can use the context structure as a parent
  66           for talloc allocations as well
  67         */
  68         ldb = ldb_init(NULL, NULL);
  69
  70         /*
  71           We now open the database. In this example we just hard code the connection path.
  72
  73           Also note that the database is being opened read-only. This means that the
  74           call will fail unless the database already exists.
  75         */
  76         if (LDB_SUCCESS != ldb_connect(ldb, "tdb://tdbtest.ldb", LDB_FLG_RDONLY, NULL) ){
  77                 printf("Problem on connection\n");
  78                 exit(-1);
  79         }
  80
  81         /*
  82           At this stage we have an open database, and can start using it. It is opened
  83           read-only, so a query is possible.
  84
  85           We construct a search that just returns all the (sensible) contents. You can do
  86           quite fine grained results with the LDAP search syntax, however it is a bit
  87           confusing to start with. See RFC2254.
  88         */
  89         if (LDB_SUCCESS != ldb_search(ldb, ldb, &resultMsg,
  90                                       NULL, LDB_SCOPE_DEFAULT, NULL,
  91                                       "%s", expression)) {
  92                 printf("Problem in search\n");
  93                 exit(-1);
  94         }
  95
  96         printf("%i records returned\n", resultMsg->count);
  97
  98         /*
  99           We can now iterate through the results, writing them out
 100           (to standard output) with our custom output routine as defined
 101           at the top of this file
 102         */
 103         for (i = 0; i < resultMsg->count; ++i) {
 104                 struct ldb_ldif ldifMsg;
 105
 106                 printf("Message: %i\n", i+1);
 107
 108                 ldifMsg.changetype = LDB_CHANGETYPE_NONE;
 109                 ldifMsg.msg = resultMsg->msgs[i];
 110                 ldb_ldif_write(ldb, vprintf_fn, NULL, &ldifMsg);
 111         }
 112
 113         /*
 114           There are two objects to clean up - the result from the
 115           ldb_search() query, and the original ldb context.
 116         */
 117         talloc_free(resultMsg);
 118
 119         talloc_free(ldb);
 120
 121         return 0;
 122 }