diff options
Diffstat (limited to 'source4/printing/printing_db.c')
| -rw-r--r-- | source4/printing/printing_db.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/source4/printing/printing_db.c b/source4/printing/printing_db.c new file mode 100644 index 0000000000..0aa8dfafa5 --- /dev/null +++ b/source4/printing/printing_db.c @@ -0,0 +1,204 @@ +/* + 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 2 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, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#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; + pstring printdb_path; + BOOL done_become_root = False; + + 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. */ + 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) { + DLIST_PROMOTE(print_db_head, p); + p = print_db_head; + } + } + + if (!p) { + /* Create one. */ + p = (struct tdb_print_db *)malloc(sizeof(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); + } + + pstrcpy(printdb_path, lock_path("printing/")); + pstrcat(printdb_path, printername); + pstrcat(printdb_path, ".tdb"); + + 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(p); + return NULL; + } + 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_by_string( 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_by_string(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(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; +} + + |