Add a timeout to tdb_lock_bystring(). Ensure we never have more than

MAX_PRINT_JOBS in a queue.
Jeremy.
(This used to be commit 9fe3c0b90d4bff2217e3cb5a34b4683ca314c06e)

12 files changed, 89 insertions, 69 deletions

diff --git a/source3/groupdb/mapping.c b/source3/groupdb/mapping.c
index 5641431246..0f05316949 100644
--- a/source3/groupdb/mapping.c
+++ b/source3/groupdb/mapping.c
@@ -223,7 +223,7 @@ static BOOL init_group_mapping(void)
 	local_pid = sys_getpid();
 
 	/* handle a Samba upgrade */
-	tdb_lock_bystring(tdb, vstring);
+	tdb_lock_bystring(tdb, vstring, 0);
 
 	/* Cope with byte-reversed older versions of the db. */
 	vers_id = tdb_fetch_int32(tdb, vstring);
diff --git a/source3/include/local.h b/source3/include/local.h
index 5096e13fc3..2be9c1e101 100644
--- a/source3/include/local.h
+++ b/source3/include/local.h
@@ -210,4 +210,7 @@
 /* this enables the "rabbit pellet" fix for SMBwritebraw */
 #define RABBIT_PELLET_FIX 1
 
+/* Max number of jobs per print queue. */
+#define PRINT_MAX_JOBID 10000
+
 #endif
diff --git a/source3/include/printing.h b/source3/include/printing.h
index 9774a6acd9..38ff7eac36 100644
--- a/source3/include/printing.h
+++ b/source3/include/printing.h
@@ -65,7 +65,7 @@ extern struct printif	generic_printif;
 extern struct printif	cups_printif;
 #endif /* HAVE_CUPS */
 
-#define PRINT_MAX_JOBID 10000
+/* PRINT_MAX_JOBID is now defined in local.h */
 #define UNIX_JOB_START PRINT_MAX_JOBID
 #define NEXT_JOBID(j) ((j+1) % PRINT_MAX_JOBID > 0 ? (j+1) % PRINT_MAX_JOBID : 1)
 
diff --git a/source3/lib/account_pol.c b/source3/lib/account_pol.c
index b5f205c508..6f51c916d7 100644
--- a/source3/lib/account_pol.c
+++ b/source3/lib/account_pol.c
@@ -45,7 +45,7 @@ BOOL init_account_policy(void)
 	local_pid = sys_getpid();
 
 	/* handle a Samba upgrade */
-	tdb_lock_bystring(tdb, vstring);
+	tdb_lock_bystring(tdb, vstring,0);
 	if (!tdb_fetch_uint32(tdb, vstring, &version) || version != DATABASE_VERSION) {
 		tdb_traverse(tdb, tdb_traverse_delete_fn, NULL);
 		tdb_store_uint32(tdb, vstring, DATABASE_VERSION);
diff --git a/source3/param/loadparm.c b/source3/param/loadparm.c
index 18cba172c0..ba0866883f 100644
--- a/source3/param/loadparm.c
+++ b/source3/param/loadparm.c
@@ -1798,7 +1798,6 @@ FN_LOCAL_INTEGER(lp_force_dir_security_mode, iDir_Security_force_mode)
 FN_LOCAL_INTEGER(lp_max_connections, iMaxConnections)
 FN_LOCAL_INTEGER(lp_defaultcase, iDefaultCase)
 FN_LOCAL_INTEGER(lp_minprintspace, iMinPrintSpace)
-FN_LOCAL_INTEGER(lp_maxprintjobs, iMaxPrintJobs)
 FN_LOCAL_INTEGER(lp_printing, iPrinting)
 FN_LOCAL_INTEGER(lp_oplock_contention_limit, iOplockContentionLimit)
 FN_LOCAL_INTEGER(lp_csc_policy, iCSCPolicy)
@@ -4070,3 +4069,16 @@ const char *get_called_name(void)
 
 	return local_machine;
 }
+
+/*******************************************************************
+ Return the max print jobs per queue.
+********************************************************************/
+
+int lp_maxprintjobs(int snum)
+{
+	int maxjobs = LP_SNUM_OK(snum) ? ServicePtrs[snum]->iMaxPrintJobs : sDefault.iMaxPrintJobs;
+	if (maxjobs <= 0 || maxjobs >= PRINT_MAX_JOBID)
+		maxjobs = PRINT_MAX_JOBID - 1;
+
+	return maxjobs;
+}
diff --git a/source3/passdb/secrets.c b/source3/passdb/secrets.c
index 4b2c76d8b0..ad56fcedd1 100644
--- a/source3/passdb/secrets.c
+++ b/source3/passdb/secrets.c
@@ -215,7 +215,7 @@ BOOL secrets_lock_trust_account_password(char *domain, BOOL dolock)
 		return False;
 
 	if (dolock)
-		return (tdb_lock_bystring(tdb, trust_keystr(domain)) == 0);
+		return (tdb_lock_bystring(tdb, trust_keystr(domain),0) == 0);
 	else
 		tdb_unlock_bystring(tdb, trust_keystr(domain));
 	return True;
@@ -579,69 +579,31 @@ NTSTATUS secrets_get_trusted_domains(TALLOC_CTX* ctx, int* enum_ctx, int max_num
 	return status;
 }
 
-static SIG_ATOMIC_T gotalarm;
+/*******************************************************************************
+ Lock the secrets tdb based on a string - this is used as a primitive form of mutex
+ between smbd instances.
+*******************************************************************************/
 
-/***************************************************************
- Signal function to tell us we timed out.
-****************************************************************/
-
-static void gotalarm_sig(void)
-{
-	gotalarm = 1;
-}
-
-/*
-  lock the secrets tdb based on a string - this is used as a primitive form of mutex
-  between smbd instances. 
-*/
 BOOL secrets_named_mutex(const char *name, unsigned int timeout)
 {
-	TDB_DATA key;
 	int ret;
 
 	if (!message_init())
 		return False;
 
-	key.dptr = (char *)name;
-	key.dsize = strlen(name)+1;
-
-	/* Allow tdb_chainlock to be interrupted by an alarm. */
-	gotalarm = 0;
-	tdb_set_lock_alarm(&gotalarm);
-
-	if (timeout) {
-		CatchSignal(SIGALRM, SIGNAL_CAST gotalarm_sig);
-		alarm(timeout);
-	}
-
-	ret = tdb_chainlock(tdb, key);
-
-	/* Prevent tdb_chainlock from being interrupted by an alarm. */
-	tdb_set_lock_alarm(NULL);
-
-	if (timeout) {
-		alarm(0);
-		CatchSignal(SIGALRM, SIGNAL_CAST SIG_IGN);
-		if (gotalarm)
-			return False;
-	}
-
+	ret = tdb_lock_bystring(tdb, name, timeout);
 	if (ret == 0)
 		DEBUG(10,("secrets_named_mutex: got mutex for %s\n", name ));
 
 	return (ret == 0);
 }
 
-/*
-  unlock a named mutex
-*/
+/*******************************************************************************
+ Unlock a named mutex.
+*******************************************************************************/
+
 void secrets_named_mutex_release(char *name)
 {
-	TDB_DATA key;
-
-	key.dptr = name;
-	key.dsize = strlen(name)+1;
-
-	tdb_chainunlock(tdb, key);
+	tdb_unlock_bystring(tdb, name);
 	DEBUG(10,("secrets_named_mutex: released mutex for %s\n", name ));
 }
diff --git a/source3/printing/nt_printing.c b/source3/printing/nt_printing.c
index 58eba9d87e..fcb493a614 100644
--- a/source3/printing/nt_printing.c
+++ b/source3/printing/nt_printing.c
@@ -287,7 +287,7 @@ BOOL nt_printing_init(void)
 	local_pid = sys_getpid();
  
 	/* handle a Samba upgrade */
-	tdb_lock_bystring(tdb_drivers, vstring);
+	tdb_lock_bystring(tdb_drivers, vstring, 0);
 	{
 		int32 vers_id;
 
@@ -362,7 +362,7 @@ uint32 update_c_setprinter(BOOL initialize)
 	int32 c_setprinter;
 	int32 printer_count = 0;
  
-	tdb_lock_bystring(tdb_printers, GLOBAL_C_SETPRINTER);
+	tdb_lock_bystring(tdb_printers, GLOBAL_C_SETPRINTER, 0);
  
 	/* Traverse the tdb, counting the printers */
 	tdb_traverse(tdb_printers, traverse_counting_printers, (void *)&printer_count);
diff --git a/source3/printing/printing.c b/source3/printing/printing.c
index 6474c92c69..91851a37f8 100644
--- a/source3/printing/printing.c
+++ b/source3/printing/printing.c
@@ -257,7 +257,7 @@ BOOL print_backend_init(void)
 		pdb = get_print_db_byname(lp_const_servicename(snum));
 		if (!pdb)
 			continue;
-		if (tdb_lock_bystring(pdb->tdb, sversion) == -1) {
+		if (tdb_lock_bystring(pdb->tdb, sversion, 0) == -1) {
 			DEBUG(0,("print_backend_init: Failed to open printer %s database\n", lp_const_servicename(snum) ));
 			return False;
 		}
@@ -883,7 +883,8 @@ static void print_queue_update(int snum)
 	/* Lock the queue for the database update */
 
 	slprintf(keystr, sizeof(keystr) - 1, "LOCK/%s", printer_name);
-	if (tdb_lock_bystring(pdb->tdb, keystr) == -1) {
+	/* Only wait 10 seconds for this. */
+	if (tdb_lock_bystring(pdb->tdb, keystr, 10) == -1) {
 		DEBUG(0,("print_queue_update: Failed to lock printer %s database\n", printer_name));
 		release_print_db(pdb);
 		return;
@@ -1380,9 +1381,8 @@ static int get_queue_status(int snum, print_status_struct *status)
 	data = tdb_fetch(pdb->tdb, key);
 	release_print_db(pdb);
 	if (data.dptr) {
-		if (data.dsize == sizeof(print_status_struct)) {
+		if (data.dsize == sizeof(print_status_struct))
 			memcpy(status, data.dptr, sizeof(print_status_struct));
-		}
 		SAFE_FREE(data.dptr);
 	}
 	return status->qcount;
@@ -1465,7 +1465,7 @@ uint32 print_job_start(struct current_user *user, int snum, char *jobname, NT_DE
 	}
 
 	/* Insure the maximum queue size is not violated */
-	if (lp_maxprintjobs(snum) && (njobs = print_queue_length(snum,NULL)) > lp_maxprintjobs(snum)) {
+	if ((njobs = print_queue_length(snum,NULL)) > lp_maxprintjobs(snum)) {
 		DEBUG(3, ("print_job_start: number of jobs (%d) larger than max printjobs per queue (%d).\n",
 			njobs, lp_maxprintjobs(snum) ));
 		release_print_db(pdb);
@@ -1473,8 +1473,8 @@ uint32 print_job_start(struct current_user *user, int snum, char *jobname, NT_DE
 		return (uint32)-1;
 	}
 
-	/* Lock the database */
-	if (tdb_lock_bystring(pdb->tdb, "INFO/nextjob") == -1) {
+	/* Lock the database - only wait 20 seconds. */
+	if (tdb_lock_bystring(pdb->tdb, "INFO/nextjob", 20) == -1) {
 		DEBUG(0,("print_job_start: failed to lock printing database %s\n", printername ));
 		release_print_db(pdb);
 		return (uint32)-1;
diff --git a/source3/rpc_server/srv_srvsvc_nt.c b/source3/rpc_server/srv_srvsvc_nt.c
index 69945b50b8..ecde51df9f 100644
--- a/source3/rpc_server/srv_srvsvc_nt.c
+++ b/source3/rpc_server/srv_srvsvc_nt.c
@@ -145,7 +145,7 @@ BOOL share_info_db_init(void)
 	local_pid = sys_getpid();
  
 	/* handle a Samba upgrade */
-	tdb_lock_bystring(share_tdb, vstring);
+	tdb_lock_bystring(share_tdb, vstring, 0);
 
 	/* Cope with byte-reversed older versions of the db. */
 	vers_id = tdb_fetch_int32(share_tdb, vstring);
diff --git a/source3/tdb/tdb.c b/source3/tdb/tdb.c
index 4143ac7781..c57d23cb6f 100644
--- a/source3/tdb/tdb.c
+++ b/source3/tdb/tdb.c
@@ -208,6 +208,10 @@ static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset,
 			TDB_LOG((tdb, 5,"tdb_brlock failed (fd=%d) at offset %d rw_type=%d lck_type=%d\n", 
 				 tdb->fd, offset, rw_type, lck_type));
 		}
+		/* Was it an alarm timeout ? */
+		if (errno == EINTR && palarm_fired && *palarm_fired)
+			return TDB_ERRCODE(TDB_ERR_LOCK_TIMEOUT, -1);
+		/* Otherwise - generic lock error. */
 		/* errno set by fcntl */
 		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
 	}
diff --git a/source3/tdb/tdb.h b/source3/tdb/tdb.h
index 42b88aeb16..dda89d0355 100644
--- a/source3/tdb/tdb.h
+++ b/source3/tdb/tdb.h
@@ -44,7 +44,7 @@ extern "C" {
 
 /* error codes */
 enum TDB_ERROR {TDB_SUCCESS=0, TDB_ERR_CORRUPT, TDB_ERR_IO, TDB_ERR_LOCK, 
-		TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOEXIST, TDB_ERR_NOLOCK };
+		TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOEXIST, TDB_ERR_NOLOCK, TDB_ERR_LOCK_TIMEOUT };
 
 #ifndef u32
 #define u32 unsigned
diff --git a/source3/tdb/tdbutil.c b/source3/tdb/tdbutil.c
index 1a3a8bb9a5..e7650033b8 100644
--- a/source3/tdb/tdbutil.c
+++ b/source3/tdb/tdbutil.c
@@ -24,18 +24,57 @@
 /* these are little tdb utility functions that are meant to make
    dealing with a tdb database a little less cumbersome in Samba */
 
+static SIG_ATOMIC_T gotalarm;
+
+/***************************************************************
+ Signal function to tell us we timed out.
+****************************************************************/
+
+static void gotalarm_sig(void)
+{
+	gotalarm = 1;
+}
+
+/****************************************************************************
+ Lock a chain with timeout (in seconds).
+****************************************************************************/
+
+int tdb_chainlock_with_timeout( TDB_CONTEXT *tdb, TDB_DATA key, unsigned int timeout)
+{
+	/* Allow tdb_chainlock to be interrupted by an alarm. */
+	int ret;
+	gotalarm = 0;
+	tdb_set_lock_alarm(&gotalarm);
+
+	if (timeout) {
+		CatchSignal(SIGALRM, SIGNAL_CAST gotalarm_sig);
+		alarm(timeout);
+	}
+
+	ret = tdb_chainlock(tdb, key);
+
+	if (timeout) {
+		alarm(0);
+		CatchSignal(SIGALRM, SIGNAL_CAST SIG_IGN);
+		if (gotalarm)
+			return -1;
+	}
+
+	return ret;
+}
+
 /****************************************************************************
- Lock a chain by string.
+ Lock a chain by string. Return -1 if timeout or lock failed.
 ****************************************************************************/
 
-int tdb_lock_bystring(TDB_CONTEXT *tdb, char *keyval)
+int tdb_lock_bystring(TDB_CONTEXT *tdb, char *keyval, unsigned int timeout)
 {
 	TDB_DATA key;
 
 	key.dptr = keyval;
 	key.dsize = strlen(keyval)+1;
 	
-	return tdb_chainlock(tdb, key);
+	return tdb_chainlock_with_timeout(tdb, key, timeout);
 }
 
 /****************************************************************************
@@ -230,7 +269,7 @@ int32 tdb_change_int32_atomic(TDB_CONTEXT *tdb, char *keystr, int32 *oldval, int
 	int32 val;
 	int32 ret = -1;
 
-	if (tdb_lock_bystring(tdb, keystr) == -1)
+	if (tdb_lock_bystring(tdb, keystr,0) == -1)
 		return -1;
 
 	if ((val = tdb_fetch_int32(tdb, keystr)) == -1) {
@@ -271,7 +310,7 @@ BOOL tdb_change_uint32_atomic(TDB_CONTEXT *tdb, char *keystr, uint32 *oldval, ui
 	uint32 val;
 	BOOL ret = False;
 
-	if (tdb_lock_bystring(tdb, keystr) == -1)
+	if (tdb_lock_bystring(tdb, keystr,0) == -1)
 		return False;
 
 	if (!tdb_fetch_uint32(tdb, keystr, &val)) {