summaryrefslogtreecommitdiff
path: root/source3/printing/queue_process.c
blob: 791f2d7a33b33df44c7ad67437eda9898401f9fe (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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
/*
   Unix SMB/Netbios implementation.
   Version 3.0
   printing backend routines
   Copyright (C) Andrew Tridgell 1992-2000
   Copyright (C) Jeremy Allison 2002
   Copyright (C) Simo Sorce 2011

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

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

#include "includes.h"
#include "smbd/globals.h"
#include "include/messages.h"
#include "printing.h"
#include "printing/pcap.h"
#include "serverid.h"
#include "locking/proto.h"
#include "smbd/proto.h"

/****************************************************************************
 Notify smbds of new printcap data
**************************************************************************/
static void reload_pcap_change_notify(struct tevent_context *ev,
			       struct messaging_context *msg_ctx)
{
	message_send_all(msg_ctx, MSG_PRINTER_PCAP, NULL, 0, NULL);
}

static bool print_queue_housekeeping(const struct timeval *now, void *pvt)
{
	struct messaging_context *msg_ctx =
		talloc_get_type_abort(pvt, struct messaging_context);
	time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
	time_t t = time_mono(NULL);

	DEBUG(5, ("print queue housekeeping\n"));

	/* if periodic printcap rescan is enabled,
	 * see if it's time to reload */
	if ((printcap_cache_time != 0) &&
	    (t >= (last_printer_reload_time + printcap_cache_time))) {
		DEBUG( 3,( "Printcap cache time expired.\n"));
		pcap_cache_reload(messaging_event_context(msg_ctx),
				  msg_ctx,
				  &reload_pcap_change_notify);
		last_printer_reload_time = t;
	}

	return true;
}

static bool printing_subsystem_queue_tasks(struct tevent_context *ev_ctx,
					   struct messaging_context *msg_ctx)
{
	if (!(event_add_idle(ev_ctx, NULL,
			     timeval_set(SMBD_HOUSEKEEPING_INTERVAL, 0),
			     "print_queue_housekeeping",
			     print_queue_housekeeping,
			     msg_ctx))) {
		DEBUG(0, ("Could not add print_queue_housekeeping event\n"));
		return false;
	}

	return true;
}

static void bq_sig_term_handler(struct tevent_context *ev,
				struct tevent_signal *se,
				int signum,
				int count,
				void *siginfo,
				void *private_data)
{
	exit_server_cleanly("termination signal");
}

void bq_setup_sig_term_handler(void)
{
	struct tevent_signal *se;

	se = tevent_add_signal(server_event_context(),
			       server_event_context(),
			       SIGTERM, 0,
			       bq_sig_term_handler,
			       NULL);
	if (!se) {
		exit_server("failed to setup SIGTERM handler");
	}
}

static void bq_sig_hup_handler(struct tevent_context *ev,
				struct tevent_signal *se,
				int signum,
				int count,
				void *siginfo,
				void *pvt)
{
	struct messaging_context *msg_ctx;

	msg_ctx = talloc_get_type_abort(pvt, struct messaging_context);
	change_to_root_user();

	DEBUG(1, ("Reloading pcap cache after SIGHUP\n"));
	pcap_cache_reload(ev, msg_ctx, &reload_pcap_change_notify);
}

static void bq_setup_sig_hup_handler(struct tevent_context *ev,
				     struct messaging_context *msg_ctx)
{
	struct tevent_signal *se;

	se = tevent_add_signal(ev, ev, SIGHUP, 0, bq_sig_hup_handler,
			       msg_ctx);
	if (!se) {
		exit_server("failed to setup SIGHUP handler");
	}
}

static void bq_smb_conf_updated(struct messaging_context *msg_ctx,
				void *private_data,
				uint32_t msg_type,
				struct server_id server_id,
				DATA_BLOB *data)
{
	struct tevent_context *ev_ctx =
		talloc_get_type_abort(private_data, struct tevent_context);

	DEBUG(10,("smb_conf_updated: Got message saying smb.conf was "
		  "updated. Reloading.\n"));
	change_to_root_user();
	pcap_cache_reload(ev_ctx, msg_ctx, &reload_pcap_change_notify);
}

static void printing_pause_fd_handler(struct tevent_context *ev,
				      struct tevent_fd *fde,
				      uint16_t flags,
				      void *private_data)
{
	/*
	 * If pause_pipe[1] is closed it means the parent smbd
	 * and children exited or aborted.
	 */
	exit_server_cleanly(NULL);
}

extern struct child_pid *children;
extern int num_children;

static void add_child_pid(pid_t pid)
{
	struct child_pid *child;

        child = SMB_MALLOC_P(struct child_pid);
        if (child == NULL) {
                DEBUG(0, ("Could not add child struct -- malloc failed\n"));
                return;
        }
        child->pid = pid;
        DLIST_ADD(children, child);
        num_children += 1;
}

pid_t background_lpq_updater_pid = -1;

/****************************************************************************
main thread of the background lpq updater
****************************************************************************/
static void start_background_queue(struct tevent_context *ev,
				   struct messaging_context *msg_ctx)
{
	/* Use local variables for this as we don't
	 * need to save the parent side of this, just
	 * ensure it closes when the process exits.
	 */
	int pause_pipe[2];

	DEBUG(3,("start_background_queue: Starting background LPQ thread\n"));

	if (pipe(pause_pipe) == -1) {
		DEBUG(5,("start_background_queue: cannot create pipe. %s\n", strerror(errno) ));
		exit(1);
	}

	background_lpq_updater_pid = sys_fork();

	if (background_lpq_updater_pid == -1) {
		DEBUG(5,("start_background_queue: background LPQ thread failed to start. %s\n", strerror(errno) ));
		exit(1);
	}

	/* Track the printing pid along with other smbd children */
	add_child_pid(background_lpq_updater_pid);

	if(background_lpq_updater_pid == 0) {
		struct tevent_fd *fde;
		int ret;
		NTSTATUS status;

		/* Child. */
		DEBUG(5,("start_background_queue: background LPQ thread started\n"));

		close(pause_pipe[0]);
		pause_pipe[0] = -1;

		status = reinit_after_fork(msg_ctx, ev, procid_self(), true);

		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(0,("reinit_after_fork() failed\n"));
			smb_panic("reinit_after_fork() failed");
		}

		bq_setup_sig_term_handler();
		bq_setup_sig_hup_handler(ev, msg_ctx);

		if (!printing_subsystem_queue_tasks(ev, msg_ctx)) {
			exit(1);
		}

		if (!serverid_register(procid_self(),
				       FLAG_MSG_GENERAL|FLAG_MSG_SMBD
				       |FLAG_MSG_PRINT_GENERAL)) {
			exit(1);
		}

		if (!locking_init()) {
			exit(1);
		}

		messaging_register(msg_ctx, ev, MSG_SMB_CONF_UPDATED,
				   bq_smb_conf_updated);
		messaging_register(msg_ctx, NULL, MSG_PRINTER_UPDATE,
				   print_queue_receive);

		fde = tevent_add_fd(ev, ev, pause_pipe[1], TEVENT_FD_READ,
				    printing_pause_fd_handler,
				    NULL);
		if (!fde) {
			DEBUG(0,("tevent_add_fd() failed for pause_pipe\n"));
			smb_panic("tevent_add_fd() failed for pause_pipe");
		}

		DEBUG(5,("start_background_queue: background LPQ thread waiting for messages\n"));
		ret = tevent_loop_wait(ev);
		/* should not be reached */
		DEBUG(0,("background_queue: tevent_loop_wait() exited with %d - %s\n",
			 ret, (ret == 0) ? "out of events" : strerror(errno)));
		exit(1);
	}

	close(pause_pipe[1]);
}

static bool use_background_queue;

/* Run before the parent forks */
bool printing_subsystem_init(struct tevent_context *ev_ctx,
			     struct messaging_context *msg_ctx,
			     bool background_queue)
{
	bool ret = true;

	use_background_queue = background_queue;

	if (!print_backend_init(msg_ctx)) {
		return false;
	}

	/* Publish nt printers, this requires a working winreg pipe */
	pcap_cache_reload(ev_ctx, msg_ctx, &reload_printers);

	if (background_queue) {
		start_background_queue(ev_ctx, msg_ctx);
	} else {
		ret = printing_subsystem_queue_tasks(ev_ctx, msg_ctx);
	}

	return ret;
}

void printing_subsystem_update(struct tevent_context *ev_ctx,
			       struct messaging_context *msg_ctx)
{
	if (use_background_queue) return;

	pcap_cache_reload(ev_ctx, msg_ctx, &reload_pcap_change_notify);
}