- added tdb_flags option to tdb_open()

- added TDB_CLEAR_IF_FIRST flag to clear the database if this is the
  first attached process. Useful for non-persistent databases like our
  locking area (this will also make upgrades to new database layouts easier)
- use lock_path() in a couple of places
- leave connections database open while smbd running
- cleaned up some tdb code a little, using macros for constants
(This used to be commit 00e9da3ca577527db392aced62f02c69cfee8f4f)

12 files changed, 72 insertions, 67 deletions

diff --git a/source3/include/proto.h b/source3/include/proto.h
index c45da94f46..251f051452 100644
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -2428,7 +2428,6 @@ void conn_free(connection_struct *conn);
 /*The following definitions come from  smbd/connection.c  */
 
 BOOL yield_connection(connection_struct *conn,char *name,int max_connections);
-int delete_dead(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf);
 BOOL claim_connection(connection_struct *conn,char *name,int max_connections,BOOL Clear);
 
 /*The following definitions come from  smbd/dfree.c  */
@@ -2856,7 +2855,8 @@ TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb);
 TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key);
 int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key);
 int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag);
-TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode);
+TDB_CONTEXT *tdb_open(char *name, int hash_size, int tdb_flags,
+		      int open_flags, mode_t mode);
 int tdb_close(TDB_CONTEXT *tdb);
 int tdb_writelock(TDB_CONTEXT *tdb);
 int tdb_writeunlock(TDB_CONTEXT *tdb);
diff --git a/source3/locking/locking.c b/source3/locking/locking.c
index 156ff016ea..dafd324edc 100644
--- a/source3/locking/locking.c
+++ b/source3/locking/locking.c
@@ -159,7 +159,7 @@ BOOL locking_init(int read_only)
 	if (tdb) return True;
 
 	tdb = tdb_open(lock_path("locking.tdb"), 
-		       0,
+		       0, TDB_CLEAR_IF_FIRST, 
 		       read_only?O_RDONLY:O_RDWR|O_CREAT,
 		       0644);
 
diff --git a/source3/nmbd/nmbd_namelistdb.c b/source3/nmbd/nmbd_namelistdb.c
index dbb8be1f2d..e2433f42d3 100644
--- a/source3/nmbd/nmbd_namelistdb.c
+++ b/source3/nmbd/nmbd_namelistdb.c
@@ -602,21 +602,15 @@ static void dump_subnet_namelist( struct subnet_record *subrec, FILE *fp)
 
 void dump_all_namelists(void)
 {
-  pstring fname;
   FILE *fp; 
   struct subnet_record *subrec;
 
-  pstrcpy(fname,lp_lockdir());
-  trim_string(fname,NULL,"/");
-  pstrcat(fname,"/"); 
-  pstrcat(fname,"namelist.debug");
-
-  fp = sys_fopen(fname,"w");
+  fp = sys_fopen(lock_path("namelist.debug"),"w");
      
   if (!fp)
   { 
     DEBUG(0,("dump_all_namelists: Can't open file %s. Error was %s\n",
-              fname,strerror(errno)));
+              "namelist.debug",strerror(errno)));
     return;
   }
       
diff --git a/source3/nmbd/nmbd_winsserver.c b/source3/nmbd/nmbd_winsserver.c
index 45e9335167..d1a100aaea 100644
--- a/source3/nmbd/nmbd_winsserver.c
+++ b/source3/nmbd/nmbd_winsserver.c
@@ -172,7 +172,6 @@ Load or create the WINS database.
 
 BOOL initialise_wins(void)
 {
-  pstring fname;
   time_t time_now = time(NULL);
   FILE *fp;
   pstring line;
@@ -182,15 +181,10 @@ BOOL initialise_wins(void)
 
   add_samba_names_to_subnet(wins_server_subnet);
 
-  pstrcpy(fname,lp_lockdir());
-  trim_string(fname,NULL,"/");
-  pstrcat(fname,"/");
-  pstrcat(fname,WINS_LIST);
-
-  if((fp = sys_fopen(fname,"r")) == NULL)
+  if((fp = sys_fopen(lock_path(WINS_LIST),"r")) == NULL)
   {
     DEBUG(2,("initialise_wins: Can't open wins database file %s. Error was %s\n",
-           fname, strerror(errno) ));
+           WINS_LIST, strerror(errno) ));
     return True;
   }
 
diff --git a/source3/smbd/connection.c b/source3/smbd/connection.c
index 5b5ab005c8..13c051a5a3 100644
--- a/source3/smbd/connection.c
+++ b/source3/smbd/connection.c
@@ -23,6 +23,7 @@
 
 
 extern fstring remote_machine;
+static TDB_CONTEXT *tdb;
 
 extern int DEBUGLEVEL;
 
@@ -33,9 +34,7 @@ BOOL yield_connection(connection_struct *conn,char *name,int max_connections)
 {
 	struct connections_key key;
 	TDB_DATA kbuf;
-	TDB_CONTEXT *tdb;
 
-	tdb = tdb_open(lock_path("connections.tdb"), 0, O_RDWR | O_CREAT, 0644);
 	if (!tdb) return False;
 
 	DEBUG(3,("Yielding connection to %s\n",name));
@@ -49,7 +48,6 @@ BOOL yield_connection(connection_struct *conn,char *name,int max_connections)
 	kbuf.dsize = sizeof(key);
 
 	tdb_delete(tdb, kbuf);
-	tdb_close(tdb);
 	return(True);
 }
 
@@ -57,30 +55,20 @@ BOOL yield_connection(connection_struct *conn,char *name,int max_connections)
 /****************************************************************************
 claim an entry in the connections database
 ****************************************************************************/
-int delete_dead(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf)
-{
-	struct connections_key key;
-	memcpy(&key, kbuf.dptr, sizeof(key));
-	if (!process_exists(key.pid)) tdb_delete(tdb, kbuf);
-	return 0;
-}
-
-
-/****************************************************************************
-claim an entry in the connections database
-****************************************************************************/
 BOOL claim_connection(connection_struct *conn,char *name,int max_connections,BOOL Clear)
 {
 	struct connections_key key;
 	struct connections_data crec;
 	TDB_DATA kbuf, dbuf;
-	TDB_CONTEXT *tdb;
 	extern int Client;
 
 	if (max_connections <= 0)
 		return(True);
-	
-	tdb = tdb_open(lock_path("connections.tdb"), 0, O_RDWR | O_CREAT, 0644);
+
+	if (!tdb) {
+		tdb = tdb_open(lock_path("connections.tdb"), 0, TDB_CLEAR_IF_FIRST, 
+			       O_RDWR | O_CREAT, 0644);
+	}
 	if (!tdb) return False;
 
 	DEBUG(5,("claiming %s %d\n",name,max_connections));
@@ -93,10 +81,6 @@ BOOL claim_connection(connection_struct *conn,char *name,int max_connections,BOO
 	kbuf.dptr = (char *)&key;
 	kbuf.dsize = sizeof(key);
 
-	if (Clear) {
-		tdb_traverse(tdb, delete_dead);
-	}
-
 	/* fill in the crec */
 	ZERO_STRUCT(crec);
 	crec.magic = 0x280267;
diff --git a/source3/tdb/tdb.c b/source3/tdb/tdb.c
index 7b8f8db4c0..731d1fdbc8 100644
--- a/source3/tdb/tdb.c
+++ b/source3/tdb/tdb.c
@@ -44,6 +44,14 @@
 #define TDB_LEN_MULTIPLIER 10
 #define FREELIST_TOP (sizeof(struct tdb_header))
 
+#define LOCK_SET 1
+#define LOCK_CLEAR 0
+
+/* lock offsets */
+#define GLOBAL_LOCK 0
+#define ACTIVE_LOCK 4
+#define LIST_LOCK_BASE 1024
+
 #define BUCKET(hash) ((hash) % tdb->header.hash_size)
 
 /* the body of the database is made of one list_struct for the free space
@@ -85,7 +93,8 @@ static char *memdup(char *d, int size)
 
 /* a byte range locking function - return 0 on success
    this functions locks/unlocks 1 byte at the specified offset */
-static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset, int set)
+static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset, 
+		      int set, int rw_type, int lck_type)
 {
 #if NOLOCK
 	return 0;
@@ -94,13 +103,13 @@ static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset, int set)
 
 	if (tdb->read_only) return -1;
 
-	fl.l_type = set?F_WRLCK:F_UNLCK;
+	fl.l_type = set==LOCK_SET?rw_type:F_UNLCK;
 	fl.l_whence = SEEK_SET;
 	fl.l_start = offset;
 	fl.l_len = 1;
 	fl.l_pid = 0;
 
-	if (fcntl(tdb->fd, F_SETLKW, &fl) != 0) {
+	if (fcntl(tdb->fd, lck_type, &fl) != 0 && lck_type == F_SETLKW) {
 #if TDB_DEBUG
 		printf("lock %d failed at %d (%s)\n", 
 		       set, offset, strerror(errno));
@@ -121,7 +130,8 @@ static int tdb_lock(TDB_CONTEXT *tdb, int list)
 		return -1;
 	}
 	if (tdb->locked[list+1] == 0) {
-		if (tdb_brlock(tdb, 4*(list+1), 1) != 0) {
+		if (tdb_brlock(tdb, LIST_LOCK_BASE + 4*list, LOCK_SET, 
+			       F_WRLCK, F_SETLKW) != 0) {
 			return -1;
 		}
 	}
@@ -146,7 +156,8 @@ static int tdb_unlock(TDB_CONTEXT *tdb, int list)
 		return -1;
 	}
 	if (tdb->locked[list+1] == 1) {
-		if (tdb_brlock(tdb, 4*(list+1), 0) != 0) {
+		if (tdb_brlock(tdb, LIST_LOCK_BASE + 4*list, LOCK_CLEAR, 
+			       F_WRLCK, F_SETLKW) != 0) {
 			return -1;
 		}
 	}
@@ -264,6 +275,8 @@ static char *tdb_alloc_read(TDB_CONTEXT *tdb, tdb_off offset, tdb_len len)
 
 	buf = (char *)malloc(len);
 
+	if (!buf) return NULL;
+
 	if (tdb_read(tdb, offset, buf, len) == -1) {
 		free(buf);
 		return NULL;
@@ -1091,7 +1104,8 @@ int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag)
 
    return is NULL on error
 */
-TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode)
+TDB_CONTEXT *tdb_open(char *name, int hash_size, int tdb_flags,
+		      int open_flags, mode_t mode)
 {
 	TDB_CONTEXT tdb, *ret;
 	struct stat st;
@@ -1100,21 +1114,36 @@ TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode)
 	tdb.name = NULL;
 	tdb.map_ptr = NULL;
 
-	if ((flags & O_ACCMODE) == O_WRONLY) goto fail;
+	if ((open_flags & O_ACCMODE) == O_WRONLY) goto fail;
 
 	if (hash_size == 0) hash_size = DEFAULT_HASH_SIZE;
 
 	memset(&tdb, 0, sizeof(tdb));
 
-	tdb.fd = open(name, flags, mode);
+	tdb.read_only = ((open_flags & O_ACCMODE) == O_RDONLY);
+
+	tdb.fd = open(name, open_flags, mode);
 	if (tdb.fd == -1) goto fail;
 
-	tdb_brlock(&tdb, 0, 1);
+	/* ensure there is only one process initialising at once */
+	tdb_brlock(&tdb, GLOBAL_LOCK, LOCK_SET, F_WRLCK, F_SETLKW);
+	
+	if (tdb_flags & TDB_CLEAR_IF_FIRST) {
+		/* we need to zero the database if we are the only
+		   one with it open */
+		if (tdb_brlock(&tdb, ACTIVE_LOCK, LOCK_SET, F_WRLCK, F_SETLK) == 0) {
+			ftruncate(tdb.fd, 0);
+			tdb_brlock(&tdb, ACTIVE_LOCK, LOCK_CLEAR, F_WRLCK, F_SETLK);
+		}
+	}
+
+	/* leave this lock in place */
+	tdb_brlock(&tdb, ACTIVE_LOCK, LOCK_SET, F_RDLCK, F_SETLKW);
 
 	if (read(tdb.fd, &tdb.header, sizeof(tdb.header)) != sizeof(tdb.header) ||
 	    tdb.header.version != TDB_VERSION) {
 		/* its not a valid database - possibly initialise it */
-		if (!(flags & O_CREAT)) {
+		if (!(open_flags & O_CREAT)) {
 			goto fail;
 		}
 		if (tdb_new_database(&tdb, hash_size) == -1) goto fail;
@@ -1131,7 +1160,6 @@ TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode)
 				   sizeof(tdb.locked[0]));
 	if (!tdb.locked) goto fail;
 	tdb.map_size = st.st_size;
-	tdb.read_only = ((flags & O_ACCMODE) == O_RDONLY);
 #if HAVE_MMAP
 	tdb.map_ptr = (void *)mmap(NULL, st.st_size, 
 				  tdb.read_only? PROT_READ : PROT_READ|PROT_WRITE,
@@ -1148,11 +1176,10 @@ TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode)
 	       hash_size, tdb.map_size);
 #endif
 
-	tdb_brlock(&tdb, 0, 0);
+	tdb_brlock(&tdb, GLOBAL_LOCK, LOCK_CLEAR, F_WRLCK, F_SETLKW);
 	return ret;
 
  fail:
-	tdb_brlock(&tdb, 0, 0);
 	if (tdb.name) free(tdb.name);
 	if (tdb.fd != -1) close(tdb.fd);
 	if (tdb.map_ptr) munmap(tdb.map_ptr, tdb.map_size);
diff --git a/source3/tdb/tdb.h b/source3/tdb/tdb.h
index 527e65740a..9cb8f71a90 100644
--- a/source3/tdb/tdb.h
+++ b/source3/tdb/tdb.h
@@ -44,16 +44,21 @@ typedef struct {
 	struct tdb_header header; /* a cached copy of the header */
 } TDB_CONTEXT;
 
+/* flags to tdb_store() */
 #define TDB_REPLACE 1
 #define TDB_INSERT 2
 
+/* flags for tdb_open() */
+#define TDB_CLEAR_IF_FIRST 1
+
 #if STANDALONE
+TDB_CONTEXT *tdb_open(char *name, int hash_size, int tdb_flags,
+		      int open_flags, mode_t mode);
 int tdb_writelock(TDB_CONTEXT *tdb);
 int tdb_writeunlock(TDB_CONTEXT *tdb);
 TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key);
 int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key);
 int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag);
-TDB_CONTEXT *tdb_open(char *name, int hash_size, int flags, mode_t mode);
 int tdb_close(TDB_CONTEXT *tdb);
 TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb);
 TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key);
diff --git a/source3/tdb/tdbtest.c b/source3/tdb/tdbtest.c
index 8089e7be7d..581d8192d9 100644
--- a/source3/tdb/tdbtest.c
+++ b/source3/tdb/tdbtest.c
@@ -180,11 +180,12 @@ static int traverse_fn(TDB_CONTEXT *db, TDB_DATA key, TDB_DATA dbuf)
 int main(int argc, char *argv[])
 {
 	int i, seed=0;
-	int loops = 50000;
+	int loops = 10000;
 
 	unlink("test.gdbm");
 
-	db = tdb_open("test.db", 0, O_RDWR | O_CREAT | O_TRUNC, 0600);
+	db = tdb_open("test.db", 0, TDB_CLEAR_IF_FIRST, 
+		      O_RDWR | O_CREAT | O_TRUNC, 0600);
 	gdbm = gdbm_open("test.gdbm", 512, GDBM_WRITER|GDBM_NEWDB|GDBM_FAST, 
 			 0600, NULL);
 
diff --git a/source3/tdb/tdbtool.c b/source3/tdb/tdbtool.c
index 5eb410d418..428bae84c2 100644
--- a/source3/tdb/tdbtool.c
+++ b/source3/tdb/tdbtool.c
@@ -41,7 +41,8 @@ static void create_tdb(void)
 		return;
 	}
 	if (tdb) tdb_close(tdb);
-	tdb = tdb_open(tok, 0, O_RDWR | O_CREAT | O_TRUNC, 0600);
+	tdb = tdb_open(tok, 0, TDB_CLEAR_IF_FIRST,
+		       O_RDWR | O_CREAT | O_TRUNC, 0600);
 }
 
 static void open_tdb(void)
@@ -52,7 +53,7 @@ static void open_tdb(void)
 		return;
 	}
 	if (tdb) tdb_close(tdb);
-	tdb = tdb_open(tok, 0, O_RDWR, 0600);
+	tdb = tdb_open(tok, 0, 0, O_RDWR, 0600);
 }
 
 static void insert_tdb(void)
diff --git a/source3/tdb/tdbtorture.c b/source3/tdb/tdbtorture.c
index 1aac6d4a01..3eb462d79e 100644
--- a/source3/tdb/tdbtorture.c
+++ b/source3/tdb/tdbtorture.c
@@ -93,13 +93,12 @@ int main(int argc, char *argv[])
 	int i, seed=0;
 	int loops = NLOOPS;
 
-	unlink("test.tdb");
-
 	for (i=0;i<NPROC-1;i++) {
 		if (fork() == 0) break;
 	}
 
-	db = tdb_open("test.tdb", 0, O_RDWR | O_CREAT, 0600);
+	db = tdb_open("test.tdb", 0, TDB_CLEAR_IF_FIRST, 
+		      O_RDWR | O_CREAT, 0600);
 	if (!db) {
 		fatal("db open failed");
 	}
diff --git a/source3/utils/status.c b/source3/utils/status.c
index 5111891492..3082402d8b 100644
--- a/source3/utils/status.c
+++ b/source3/utils/status.c
@@ -261,11 +261,11 @@ static int traverse_fn1(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf)
 		case 's':
 			pstrcpy(servicesf, optarg);
 			break;
-		case 'u':                                       /* added by OH */
-			Ucrit_addUsername(optarg);                    /* added by OH */
+		case 'u':                                      
+			Ucrit_addUsername(optarg);             
 			break;
 		default:
-			fprintf(stderr, "Usage: %s [-P] [-d] [-L] [-p] [-S] [-s configfile] [-u username]\n", *argv); /* changed by OH */
+			fprintf(stderr, "Usage: %s [-P] [-d] [-L] [-p] [-S] [-s configfile] [-u username]\n", *argv);
 			return (-1);
 		}
 	}
@@ -283,7 +283,7 @@ static int traverse_fn1(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf)
 		return profile_dump();
 	}
 	
-	tdb = tdb_open(lock_path("connections.tdb"), 0, O_RDONLY, 0);
+	tdb = tdb_open(lock_path("connections.tdb"), 0, 0, O_RDONLY, 0);
 	if (!tdb) {
 		printf("connections.tdb not initialised\n");
 		if (!lp_status(-1))
diff --git a/source3/web/statuspage.c b/source3/web/statuspage.c
index e3e10f09d5..eaf3fdb864 100644
--- a/source3/web/statuspage.c
+++ b/source3/web/statuspage.c
@@ -172,7 +172,7 @@ void status_page(void)
 		refresh_interval = atoi(v);
 	}
 
-	tdb = tdb_open(lock_path("connections.tdb"), 0, O_RDONLY, 0);
+	tdb = tdb_open(lock_path("connections.tdb"), 0, 0, O_RDONLY, 0);
 	if (tdb) tdb_traverse(tdb, traverse_fn1);
 
 	printf("<H2>Server Status</H2>\n");