diff options
Diffstat (limited to 'source3/printing/printing.c')
| -rw-r--r-- | source3/printing/printing.c | 171 |
1 files changed, 136 insertions, 35 deletions
diff --git a/source3/printing/printing.c b/source3/printing/printing.c index 5c8790e34b..b5785440ae 100644 --- a/source3/printing/printing.c +++ b/source3/printing/printing.c @@ -44,9 +44,9 @@ static BOOL remove_from_jobs_changed(const char* sharename, uint32 jobid); */ struct print_queue_update_context { - fstring sharename; + char* sharename; enum printing_types printing_type; - pstring lpqcommand; + char* lpqcommand; }; @@ -993,16 +993,17 @@ static void check_job_changed(const char *sharename, TDB_DATA data, uint32 jobid Check if the print queue has been updated recently enough. ****************************************************************************/ -static BOOL print_cache_expired(const char *sharename) +static BOOL print_cache_expired(const char *sharename, BOOL check_pending) { fstring key; time_t last_qscan_time, time_now = time(NULL); struct tdb_print_db *pdb = get_print_db_byname(sharename); + BOOL result = False; if (!pdb) return False; - slprintf(key, sizeof(key), "CACHE/%s", sharename); + snprintf(key, sizeof(key), "CACHE/%s", sharename); last_qscan_time = (time_t)tdb_fetch_int32(pdb->tdb, key); /* @@ -1019,15 +1020,37 @@ static BOOL print_cache_expired(const char *sharename) || (time_now - last_qscan_time) >= lp_lpqcachetime() || last_qscan_time > (time_now + MAX_CACHE_VALID_TIME)) { - DEBUG(3, ("print cache expired for queue %s " + time_t msg_pending_time; + + DEBUG(4, ("print_cache_expired: cache expired for queue %s " "(last_qscan_time = %d, time now = %d, qcachetime = %d)\n", sharename, (int)last_qscan_time, (int)time_now, (int)lp_lpqcachetime() )); - release_print_db(pdb); - return True; + + /* check if another smbd has already sent a message to update the + queue. Give the pending message one minute to clear and + then send another message anyways. Make sure to check for + clocks that have been run forward and then back again. */ + + snprintf(key, sizeof(key), "MSG_PENDING/%s", sharename); + + if ( check_pending + && tdb_fetch_uint32( pdb->tdb, key, &msg_pending_time ) + && msg_pending_time > 0 + && msg_pending_time <= time_now + && (time_now - msg_pending_time) < 60 ) + { + DEBUG(4,("print_cache_expired: message already pending for %s. Accepting cache\n", + sharename)); + goto done; + } + + result = True; } + +done: release_print_db(pdb); - return False; + return result; } /**************************************************************************** @@ -1052,7 +1075,7 @@ static void print_queue_update_internal( const char *sharename, DEBUG(5,("print_queue_update_internal: printer = %s, type = %d, lpq command = [%s]\n", sharename, current_printif->type, lpq_command)); - if ( !print_cache_expired(sharename) ) { + if ( !print_cache_expired(sharename, False) ) { DEBUG(5,("print_queue_update_internal: print cache for %s is still ok\n", sharename)); return; } @@ -1166,6 +1189,20 @@ static void print_queue_update_internal( const char *sharename, slprintf(keystr, sizeof(keystr)-1, "CACHE/%s", sharename); tdb_store_int32(pdb->tdb, keystr, (int32)time(NULL)); + /* clear the msg pending record for this queue */ + + snprintf(keystr, sizeof(keystr), "MSG_PENDING/%s", sharename); + + if ( !tdb_store_uint32( pdb->tdb, keystr, 0 ) ) { + /* log a message but continue on */ + + DEBUG(0,("print_queue_update: failed to store MSG_PENDING flag for [%s]!\n", + sharename)); + } + + release_print_db( pdb ); + + return; } /**************************************************************************** @@ -1255,19 +1292,31 @@ static void print_queue_update_with_lock(int snum) /**************************************************************************** this is the receive function of the background lpq updater ****************************************************************************/ -static void print_queue_receive(int msg_type, pid_t src, void *buf, size_t len) +static void print_queue_receive(int msg_type, pid_t src, void *buf, size_t msglen) { struct print_queue_update_context ctx; + fstring sharename; + pstring lpqcommand; + size_t len; + + len = tdb_unpack( buf, msglen, "fdP", + sharename, + &ctx.printing_type, + lpqcommand ); - if (len != sizeof(struct print_queue_update_context)) { - DEBUG(1, ("Got invalid print queue update message\n")); + if ( len == -1 ) { + DEBUG(0,("print_queue_receive: Got invalid print queue update message\n")); return; } - memcpy(&ctx, buf, sizeof(struct print_queue_update_context)); + ctx.sharename = sharename; + ctx.lpqcommand = lpqcommand; + print_queue_update_internal(ctx.sharename, get_printer_fns_from_type(ctx.printing_type), ctx.lpqcommand ); + + return; } static pid_t background_lpq_updater_pid = -1; @@ -1333,32 +1382,84 @@ update the internal database from the system print queue for a queue static void print_queue_update(int snum) { struct print_queue_update_context ctx; + fstring key; + fstring sharename; + pstring lpqcommand; + char *buffer = NULL; + size_t len = 0; + size_t newlen; + struct tdb_print_db *pdb; /* * Make sure that the background queue process exists. * Otherwise just do the update ourselves */ - - if ( background_lpq_updater_pid != -1 ) { - fstrcpy(ctx.sharename, lp_const_servicename(snum)); - ctx.printing_type = lp_printing(snum); + + if ( background_lpq_updater_pid == -1 ) { + print_queue_update_with_lock( snum ); + return; + } + + fstrcpy( sharename, lp_const_servicename(snum)); + + ctx.printing_type = lp_printing(snum); + + pstrcpy( lpqcommand, lp_lpqcommand(snum)); + pstring_sub( lpqcommand, "%p", PRINTERNAME(snum) ); + standard_sub_snum( snum, lpqcommand, sizeof(lpqcommand) ); + + ctx.sharename = SMB_STRDUP( sharename ); + ctx.lpqcommand = SMB_STRDUP( lpqcommand ); + + /* get the length */ + + len = tdb_pack( buffer, len, "fdP", + ctx.sharename, + ctx.printing_type, + ctx.lpqcommand ); - pstrcpy(ctx.lpqcommand, lp_lpqcommand(snum)); - pstring_sub( ctx.lpqcommand, "%p", PRINTERNAME(snum) ); - standard_sub_snum( snum, ctx.lpqcommand, sizeof(ctx.lpqcommand) ); + buffer = SMB_XMALLOC_ARRAY( char, len ); - DEBUG(10,("print_queue_update: Sending message -> printer = %s, " - "type = %d, lpq command = [%s]\n", - ctx.sharename, ctx.printing_type, ctx.lpqcommand )); + /* now pack the buffer */ + newlen = tdb_pack( buffer, len, "fdP", + ctx.sharename, + ctx.printing_type, + ctx.lpqcommand ); + + SMB_ASSERT( newlen == len ); + + DEBUG(10,("print_queue_update: Sending message -> printer = %s, " + "type = %d, lpq command = [%s]\n", + ctx.sharename, ctx.printing_type, ctx.lpqcommand )); + + /* here we set a msg pending record for other smbd processes + to throttle the number of duplicate print_queue_update msgs + sent. */ + + pdb = get_print_db_byname(sharename); + snprintf(key, sizeof(key), "MSG_PENDING/%s", sharename); + + if ( !tdb_store_uint32( pdb->tdb, key, time(NULL) ) ) { + /* log a message but continue on */ + + DEBUG(0,("print_queue_update: failed to store MSG_PENDING flag for [%s]!\n", + sharename)); + } + + release_print_db( pdb ); + /* finally send the message */ - become_root(); - message_send_pid(background_lpq_updater_pid, - MSG_PRINTER_UPDATE, &ctx, sizeof(ctx), - False); - unbecome_root(); - } else - print_queue_update_with_lock( snum ); + become_root(); + message_send_pid(background_lpq_updater_pid, + MSG_PRINTER_UPDATE, buffer, len, False); + unbecome_root(); + + SAFE_FREE( ctx.sharename ); + SAFE_FREE( ctx.lpqcommand ); + SAFE_FREE( buffer ); + + return; } /**************************************************************************** @@ -2001,7 +2102,7 @@ int print_queue_length(int snum, print_status_struct *pstatus) int len; /* make sure the database is up to date */ - if (print_cache_expired(lp_const_servicename(snum))) + if (print_cache_expired(lp_const_servicename(snum), True)) print_queue_update(snum); /* also fetch the queue status */ @@ -2316,7 +2417,7 @@ BOOL print_job_end(int snum, uint32 jobid, BOOL normal_close) pjob_store(sharename, jobid, pjob); /* make sure the database is up to date */ - if (print_cache_expired(lp_const_servicename(snum))) + if (print_cache_expired(lp_const_servicename(snum), True)) print_queue_update(snum); return True; @@ -2348,7 +2449,7 @@ static BOOL get_stored_queue_info(struct tdb_print_db *pdb, int snum, int *pcoun const char* sharename = lp_servicename(snum); /* make sure the database is up to date */ - if (print_cache_expired(lp_const_servicename(snum))) + if (print_cache_expired(lp_const_servicename(snum), True)) print_queue_update(snum); *pcount = 0; @@ -2469,7 +2570,7 @@ int print_queue_status(int snum, /* make sure the database is up to date */ - if (print_cache_expired(lp_const_servicename(snum))) + if (print_cache_expired(lp_const_servicename(snum), True)) print_queue_update(snum); /* return if we are done */ @@ -2569,7 +2670,7 @@ BOOL print_queue_resume(struct current_user *user, int snum, WERROR *errcode) } /* make sure the database is up to date */ - if (print_cache_expired(lp_const_servicename(snum))) + if (print_cache_expired(lp_const_servicename(snum), True)) print_queue_update(snum); /* Send a printer notify message */ |