/* Unix SMB/Netbios implementation. Version 3.0 printing backend routines Copyright (C) Andrew Tridgell 1992-2000 Copyright (C) Jeremy Allison 2002 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 "printing.h" static struct tdb_print_db *print_db_head; /**************************************************************************** Function to find or create the printer specific job tdb given a printername. Limits the number of tdb's open to MAX_PRINT_DBS_OPEN. ****************************************************************************/ struct tdb_print_db *get_print_db_byname(const char *printername) { struct tdb_print_db *p = NULL, *last_entry = NULL; int num_open = 0; char *printdb_path = NULL; bool done_become_root = False; SMB_ASSERT(printername != NULL); for (p = print_db_head, last_entry = print_db_head; p; p = p->next) { /* Ensure the list terminates... JRA. */ SMB_ASSERT(p->next != print_db_head); if (p->tdb && strequal(p->printer_name, printername)) { DLIST_PROMOTE(print_db_head, p); p->ref_count++; return p; } num_open++; last_entry = p; } /* Not found. */ if (num_open >= MAX_PRINT_DBS_OPEN) { /* Try and recycle the last entry. */ if (print_db_head && last_entry) { DLIST_PROMOTE(print_db_head, last_entry); } for (p = print_db_head; p; p = p->next) { if (p->ref_count) continue; if (p->tdb) { if (tdb_close(print_db_head->tdb)) { DEBUG(0,("get_print_db: Failed to close tdb for printer %s\n", print_db_head->printer_name )); return NULL; } } p->tdb = NULL; p->ref_count = 0; memset(p->printer_name, '\0', sizeof(p->printer_name)); break; } if (p && print_db_head) { DLIST_PROMOTE(print_db_head, p); p = print_db_head; } } if (!p) { /* Create one. */ p = SMB_MALLOC_P(struct tdb_print_db); if (!p) { DEBUG(0,("get_print_db: malloc fail !\n")); return NULL; } ZERO_STRUCTP(p); DLIST_ADD(print_db_head, p); } if (asprintf(&printdb_path, "%s%s.tdb", lock_path("printing/"), printername) < 0) { DLIST_REMOVE(print_db_head, p); SAFE_FREE(p); return NULL; } if (geteuid() != 0) { become_root(); done_become_root = True; } p->tdb = tdb_open_log(printdb_path, 5000, TDB_DEFAULT, O_RDWR|O_CREAT, 0600); if (done_become_root) unbecome_root(); if (!p->tdb) { DEBUG(0,("get_print_db: Failed to open printer backend database %s.\n", printdb_path )); DLIST_REMOVE(print_db_head, p); SAFE_FREE(printdb_path); SAFE_FREE(p); return NULL; } SAFE_FREE(printdb_path); fstrcpy(p->printer_name, printername); p->ref_count++; return p; } /*************************************************************************** Remove a reference count. ****************************************************************************/ void release_print_db( struct tdb_print_db *pdb) { pdb->ref_count--; SMB_ASSERT(pdb->ref_count >= 0); } /*************************************************************************** Close all open print db entries. ****************************************************************************/ void close_all_print_db(void) { struct tdb_print_db *p = NULL, *next_p = NULL; for (p = print_db_head; p; p = next_p) { next_p = p->next; if (p->tdb) tdb_close(p->tdb); DLIST_REMOVE(print_db_head, p); ZERO_STRUCTP(p); SAFE_FREE(p); } } /**************************************************************************** Fetch and clean the pid_t record list for all pids interested in notify messages. data needs freeing on exit. ****************************************************************************/ TDB_DATA get_printer_notify_pid_list(TDB_CONTEXT *tdb, const char *printer_name, bool cleanlist) { TDB_DATA data; size_t i; ZERO_STRUCT(data); data = tdb_fetch_bystring( tdb, NOTIFY_PID_LIST_KEY ); if (!data.dptr) { ZERO_STRUCT(data); return data; } if (data.dsize % 8) { DEBUG(0,("get_printer_notify_pid_list: Size of record for printer %s not a multiple of 8 !\n", printer_name )); tdb_delete_bystring(tdb, NOTIFY_PID_LIST_KEY ); SAFE_FREE(data.dptr); ZERO_STRUCT(data); return data; } if (!cleanlist) return data; /* * Weed out all dead entries. */ for( i = 0; i < data.dsize; i += 8) { pid_t pid = (pid_t)IVAL(data.dptr, i); if (pid == sys_getpid()) continue; /* Entry is dead if process doesn't exist or refcount is zero. */ while ((i < data.dsize) && ((IVAL(data.dptr, i + 4) == 0) || !process_exists_by_pid(pid))) { /* Refcount == zero is a logic error and should never happen. */ if (IVAL(data.dptr, i + 4) == 0) { DEBUG(0,("get_printer_notify_pid_list: Refcount == 0 for pid = %u printer %s !\n", (unsigned int)pid, printer_name )); } if (data.dsize - i > 8) memmove( &data.dptr[i], &data.dptr[i+8], data.dsize - i - 8); data.dsize -= 8; } } return data; }