source/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 2 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, write to the Free Software
  22    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23    Boston, MA  02110-1301  USA
  24 */
  25
  26 /** \example ldbreader.c
  27
  28 The code below shows a simple LDB application.
  29
  30 It lists / dumps the records in a LDB database to standard output.
  31
  32 */
  33
  34 #include "includes.h"
  35 #include "ldb/include/ldb.h"
  36 #include "ldb/include/ldb_errors.h"
  37
  38 /*
  39   ldb_ldif_write takes a function pointer to a custom output
  40   function. This version is about as simple as the output function can
  41   be. In a more complex example, you'd likely be doing something with
  42   the private data function (e.g. holding a file handle).
  43 */
  44 static int vprintf_fn(void *private_data, const char *fmt, ...)
  45 {
  46         int retval;
  47         va_list ap;
  48
  49         va_start(ap, fmt);
  50         /* We just write to standard output */
  51         retval = vprintf(fmt, ap);
  52         va_end(ap);
  53         /* Note that the function should return the number of
  54            bytes written, or a negative error code */
  55         return retval;
  56 }
  57
  58 int main(int argc, const char **argv)
  59 {
  60         struct ldb_context *ldb;
  61         const char *expression = "(dn=*)";
  62         struct ldb_result *resultMsg;
  63         int i;
  64
  65         /*
  66           This is the always the first thing you want to do in an LDB
  67           application - initialise up the context structure.
  68
  69           Note that you can use the context structure as a parent
  70           for talloc allocations as well
  71         */
  72         ldb = ldb_init(NULL);
  73
  74         /*
  75           We now open the database. In this example we just hard code the connection path.
  76
  77           Also note that the database is being opened read-only. This means that the
  78           call will fail unless the database already exists.
  79         */
  80         if (LDB_SUCCESS != ldb_connect(ldb, "tdb://tdbtest.ldb", LDB_FLG_RDONLY, NULL) ){
  81                 printf("Problem on connection\n");
  82                 exit(-1);
  83         }
  84
  85         /*
  86           At this stage we have an open database, and can start using it. It is opened
  87           read-only, so a query is possible.
  88
  89           We construct a search that just returns all the (sensible) contents. You can do
  90           quite fine grained results with the LDAP search syntax, however it is a bit
  91           confusing to start with. See RFC2254.
  92         */
  93         if (LDB_SUCCESS != ldb_search(ldb, NULL, LDB_SCOPE_DEFAULT,
  94                                       expression, NULL, &resultMsg) ) {
  95                 printf("Problem in search\n");
  96                 exit(-1);
  97         }
  98
  99         printf("%i records returned\n", resultMsg->count);
 100
 101         /*
 102           We can now iterate through the results, writing them out
 103           (to standard output) with our custom output routine as defined
 104           at the top of this file
 105         */
 106         for (i = 0; i < resultMsg->count; ++i) {
 107                 struct ldb_ldif ldifMsg;
 108
 109                 printf("Message: %i\n", i+1);
 110
 111                 ldifMsg.changetype = LDB_CHANGETYPE_NONE;
 112                 ldifMsg.msg = resultMsg->msgs[i];
 113                 ldb_ldif_write(ldb, vprintf_fn, NULL, &ldifMsg);
 114         }
 115
 116         /*
 117           There are two objects to clean up - the result from the
 118           ldb_search() query, and the original ldb context.
 119         */
 120         talloc_free(resultMsg);
 121
 122         talloc_free(ldb);
 123
 124         return 0;
 125 }