summaryrefslogtreecommitdiffstats
path: root/ldb/ldb_tdb/ldb_tdb_wrap.c
blob: 4fea43c8c805b183f234313d98e79ae5fb030d86 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
/* 
   ldb database library

   Copyright (C) Andrew Tridgell  2005

     ** NOTE! The following LGPL license applies to the ldb
     ** library. This does NOT imply that all of Samba is released
     ** under the LGPL
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/

#include "ldb_includes.h"

#include "ldb_tdb.h"

/*
  the purpose of this code is to work around the braindead posix locking
  rules, to allow us to have a ldb open more than once while allowing 
  locking to work
*/

struct ltdb_wrap {
	struct ltdb_wrap *next, *prev;
	struct tdb_context *tdb;
	dev_t device;
	ino_t inode;
};

static struct ltdb_wrap *tdb_list;

/* destroy the last connection to a tdb */
static int ltdb_wrap_destructor(struct ltdb_wrap *w)
{
	tdb_close(w->tdb);
	if (w->next) {
		w->next->prev = w->prev;
	}
	if (w->prev) {
		w->prev->next = w->next;
	}
	if (w == tdb_list) {
		tdb_list = w->next;
	}
	return 0;
}				 

static void ltdb_log_fn(struct tdb_context *tdb, enum tdb_debug_level level, const char *fmt, ...) PRINTF_ATTRIBUTE(3, 4);
static void ltdb_log_fn(struct tdb_context *tdb, enum tdb_debug_level level, const char *fmt, ...)
{
	va_list ap;
	const char *name = tdb_name(tdb);
	struct ldb_context *ldb = talloc_get_type(tdb_get_logging_private(tdb), struct ldb_context);
	enum ldb_debug_level ldb_level;
	char *message; 

	if (ldb == NULL)
		return;

	va_start(ap, fmt);
	message = talloc_vasprintf(ldb, fmt, ap);
	va_end(ap);

	switch (level) {
	case TDB_DEBUG_FATAL:
		ldb_level = LDB_DEBUG_FATAL;
		break;
	case TDB_DEBUG_ERROR:
		ldb_level = LDB_DEBUG_ERROR;
		break;
	case TDB_DEBUG_WARNING:
		ldb_level = LDB_DEBUG_WARNING;
		break;
	case TDB_DEBUG_TRACE:
		ldb_level = LDB_DEBUG_TRACE;
		break;
	default:
		ldb_level = LDB_DEBUG_FATAL;
	}

	ldb_debug(ldb, ldb_level, "ltdb: tdb(%s): %s", name, message);
	talloc_free(message);
}

/*
  wrapped connection to a tdb database. The caller should _not_ free
  this as it is not a talloc structure (as tdb does not use talloc
  yet). It will auto-close when the caller frees the mem_ctx that is
  passed to this call
 */
struct tdb_context *ltdb_wrap_open(TALLOC_CTX *mem_ctx,
				   const char *path, int hash_size, 
				   int tdb_flags,
				   int open_flags, mode_t mode, 
				   struct ldb_context *ldb)
{
	struct ltdb_wrap *w;
	struct stat st;
	struct tdb_logging_context log_ctx;

	log_ctx.log_fn = ltdb_log_fn;
	log_ctx.log_private = ldb;

	if (stat(path, &st) == 0) {
		for (w=tdb_list;w;w=w->next) {
			if (st.st_dev == w->device && st.st_ino == w->inode) {
				if (!talloc_reference(mem_ctx, w)) {
					return NULL;
				}
				return w->tdb;
			}
		}
	}

	w = talloc(mem_ctx, struct ltdb_wrap);
	if (w == NULL) {
		return NULL;
	}

	w->tdb = tdb_open_ex(path, hash_size, tdb_flags, open_flags, mode, &log_ctx, NULL);
	if (w->tdb == NULL) {
		talloc_free(w);
		return NULL;
	}

	if (fstat(tdb_fd(w->tdb), &st) != 0) {
		tdb_close(w->tdb);
		talloc_free(w);
		return NULL;
	}

	w->device = st.st_dev;
	w->inode  = st.st_ino;

	talloc_set_destructor(w, ltdb_wrap_destructor);

	w->next = tdb_list;
	w->prev = NULL;
	if (tdb_list) {
		tdb_list->prev = w;
	}
	tdb_list = w;
	
	return w->tdb;
}