tevent: call epoll_panic() if EPOLL_CTL_DEL failed
[Samba/gebeck_regimport.git] / source3 / printing / printing_db.c
blobecb8ff6463cffa579f2e86bd02f4b7c17ad154c2
1 /*
2 Unix SMB/Netbios implementation.
3 Version 3.0
4 printing backend routines
5 Copyright (C) Andrew Tridgell 1992-2000
6 Copyright (C) Jeremy Allison 2002
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include "includes.h"
23 #include "system/passwd.h" /* uid_wrapper */
24 #include "system/filesys.h"
25 #include "printing.h"
26 #include "util_tdb.h"
28 static struct tdb_print_db *print_db_head;
30 /****************************************************************************
31 Function to find or create the printer specific job tdb given a printername.
32 Limits the number of tdb's open to MAX_PRINT_DBS_OPEN.
33 ****************************************************************************/
35 struct tdb_print_db *get_print_db_byname(const char *printername)
37 struct tdb_print_db *p = NULL, *last_entry = NULL;
38 int num_open = 0;
39 char *printdb_path = NULL;
40 bool done_become_root = False;
42 SMB_ASSERT(printername != NULL);
44 for (p = print_db_head, last_entry = print_db_head; p; p = p->next) {
45 /* Ensure the list terminates... JRA. */
46 SMB_ASSERT(p->next != print_db_head);
48 if (p->tdb && strequal(p->printer_name, printername)) {
49 DLIST_PROMOTE(print_db_head, p);
50 p->ref_count++;
51 return p;
53 num_open++;
54 last_entry = p;
57 /* Not found. */
58 if (num_open >= MAX_PRINT_DBS_OPEN) {
59 /* Try and recycle the last entry. */
60 if (print_db_head && last_entry) {
61 DLIST_PROMOTE(print_db_head, last_entry);
64 for (p = print_db_head; p; p = p->next) {
65 if (p->ref_count)
66 continue;
67 if (p->tdb) {
68 if (tdb_close(print_db_head->tdb)) {
69 DEBUG(0,("get_print_db: Failed to close tdb for printer %s\n",
70 print_db_head->printer_name ));
71 return NULL;
74 p->tdb = NULL;
75 p->ref_count = 0;
76 memset(p->printer_name, '\0', sizeof(p->printer_name));
77 break;
79 if (p && print_db_head) {
80 DLIST_PROMOTE(print_db_head, p);
81 p = print_db_head;
85 if (!p) {
86 /* Create one. */
87 p = SMB_MALLOC_P(struct tdb_print_db);
88 if (!p) {
89 DEBUG(0,("get_print_db: malloc fail !\n"));
90 return NULL;
92 ZERO_STRUCTP(p);
93 DLIST_ADD(print_db_head, p);
96 if (asprintf(&printdb_path, "%s%s.tdb",
97 cache_path("printing/"),
98 printername) < 0) {
99 DLIST_REMOVE(print_db_head, p);
100 SAFE_FREE(p);
101 return NULL;
104 if (geteuid() != sec_initial_uid()) {
105 become_root();
106 done_become_root = True;
109 p->tdb = tdb_open_log(printdb_path, 5000, TDB_DEFAULT, O_RDWR|O_CREAT,
110 0600);
112 if (done_become_root)
113 unbecome_root();
115 if (!p->tdb) {
116 DEBUG(0,("get_print_db: Failed to open printer backend database %s.\n",
117 printdb_path ));
118 DLIST_REMOVE(print_db_head, p);
119 SAFE_FREE(printdb_path);
120 SAFE_FREE(p);
121 return NULL;
123 SAFE_FREE(printdb_path);
124 fstrcpy(p->printer_name, printername);
125 p->ref_count++;
126 return p;
129 /***************************************************************************
130 Remove a reference count.
131 ****************************************************************************/
133 void release_print_db( struct tdb_print_db *pdb)
135 pdb->ref_count--;
136 SMB_ASSERT(pdb->ref_count >= 0);
139 /***************************************************************************
140 Close all open print db entries.
141 ****************************************************************************/
143 void close_all_print_db(void)
145 struct tdb_print_db *p = NULL, *next_p = NULL;
147 for (p = print_db_head; p; p = next_p) {
148 next_p = p->next;
150 if (p->tdb)
151 tdb_close(p->tdb);
152 DLIST_REMOVE(print_db_head, p);
153 ZERO_STRUCTP(p);
154 SAFE_FREE(p);
159 /****************************************************************************
160 Fetch and clean the pid_t record list for all pids interested in notify
161 messages. data needs freeing on exit.
162 ****************************************************************************/
164 TDB_DATA get_printer_notify_pid_list(struct tdb_context *tdb, const char *printer_name, bool cleanlist)
166 TDB_DATA data;
167 size_t i;
169 ZERO_STRUCT(data);
171 data = tdb_fetch_bystring( tdb, NOTIFY_PID_LIST_KEY );
173 if (!data.dptr) {
174 ZERO_STRUCT(data);
175 return data;
178 if (data.dsize % 8) {
179 DEBUG(0,("get_printer_notify_pid_list: Size of record for printer %s not a multiple of 8 !\n", printer_name ));
180 tdb_delete_bystring(tdb, NOTIFY_PID_LIST_KEY );
181 SAFE_FREE(data.dptr);
182 ZERO_STRUCT(data);
183 return data;
186 if (!cleanlist)
187 return data;
190 * Weed out all dead entries.
193 for( i = 0; i < data.dsize; i += 8) {
194 pid_t pid = (pid_t)IVAL(data.dptr, i);
196 if (pid == getpid())
197 continue;
199 /* Entry is dead if process doesn't exist or refcount is zero. */
201 while ((i < data.dsize) && ((IVAL(data.dptr, i + 4) == 0) || !process_exists_by_pid(pid))) {
203 /* Refcount == zero is a logic error and should never happen. */
204 if (IVAL(data.dptr, i + 4) == 0) {
205 DEBUG(0,("get_printer_notify_pid_list: Refcount == 0 for pid = %u printer %s !\n",
206 (unsigned int)pid, printer_name ));
209 if (data.dsize - i > 8)
210 memmove( &data.dptr[i], &data.dptr[i+8], data.dsize - i - 8);
211 data.dsize -= 8;
215 return data;