much cleaner chain pointer handling for both files and pipes.

the chain pointer is now stored as a static and is set whenever a
handle is created or extracted. This also makes the code less error
prone.
(This used to be commit 068a862982bea726e8d7b1b4065d510b9840a272)

6 files changed, 67 insertions, 60 deletions

diff --git a/source3/smbd/files.c b/source3/smbd/files.c
index bc3ea880bf..e66e53e6ed 100644
--- a/source3/smbd/files.c
+++ b/source3/smbd/files.c
@@ -35,6 +35,10 @@ static struct bitmap *fd_bmap;
 
 static files_struct *Files;
 
+/* a fsp to use when chaining */
+static files_struct *chain_fsp = NULL;
+
+
 /*
  * Indirection for file fd's. Needed as POSIX locking
  * is based on file/process, not fd/process.
@@ -106,6 +110,8 @@ files_struct *file_new(void )
 
 	DEBUG(5,("allocated file structure %d (%d used)\n",
 		 i, files_used));
+
+	chain_fsp = fsp;
 	
 	return fsp;
 }
@@ -238,21 +244,6 @@ void file_init(void)
 
 
 /****************************************************************************
-find a fsp given a fnum
-****************************************************************************/
-files_struct *file_fsp(int fnum)
-{
-	files_struct *fsp;
-
-	for (fsp=Files;fsp;fsp=fsp->next) {
-		if (fsp->fnum == fnum) return fsp;
-	}
-
-	return NULL;
-}
-
-
-/****************************************************************************
 close files open by a specified vuid
 ****************************************************************************/
 void file_close_user(int vuid)
@@ -375,5 +366,39 @@ void file_free(files_struct *fsp)
 	   information */
 	memset(fsp, 0, sizeof(*fsp));
 
+	if (fsp == chain_fsp) chain_fsp = NULL;
+
 	free(fsp);
 }
+
+
+/****************************************************************************
+get a fsp from a packet given the offset of a 16 bit fnum
+****************************************************************************/
+files_struct *file_fsp(char *buf, int where)
+{
+	int fnum;
+	files_struct *fsp;
+
+	if (chain_fsp) return chain_fsp;
+
+	fnum = SVAL(buf, where);
+
+	for (fsp=Files;fsp;fsp=fsp->next) {
+		if (fsp->fnum == fnum) {
+			chain_fsp = fsp;
+			return fsp;
+		}
+	}
+
+	return NULL;
+}
+
+
+/****************************************************************************
+reset the chained fsp - done at the start of a packet reply
+****************************************************************************/
+void file_chain_reset(void)
+{
+	chain_fsp = NULL;
+}
diff --git a/source3/smbd/nttrans.c b/source3/smbd/nttrans.c
index 31bfac25c8..89efd7ccd7 100644
--- a/source3/smbd/nttrans.c
+++ b/source3/smbd/nttrans.c
@@ -24,7 +24,6 @@
 
 extern int DEBUGLEVEL;
 extern int Protocol;
-extern files_struct *chain_fsp;
 extern int Client;  
 extern int oplock_sock;
 extern int smb_read_error;
@@ -665,8 +664,6 @@ int reply_ntcreate_and_X(connection_struct *conn,
 		SCVAL(p,0,fsp->is_directory ? 1 : 0);
 	}
 	
-	chain_fsp = fsp;
-
 	DEBUG(5,("reply_ntcreate_and_X: open name = %s\n",
 		 fsp?fsp->fsp_name:"NULL"));
 
@@ -941,7 +938,7 @@ static int call_nt_transact_rename(connection_struct *conn,
 {
   char *params = *ppparams;
   pstring new_name;
-  files_struct *fsp = GETFSP(params, 0);
+  files_struct *fsp = file_fsp(params, 0);
   BOOL replace_if_exists = (SVAL(params,2) & RENAME_REPLACE_IF_EXISTS) ? True : False;
   uint32 fname_len = MIN((((uint32)IVAL(inbuf,smb_nt_TotalParameterCount)-4)),
                          ((uint32)sizeof(new_name)-1));
@@ -1166,7 +1163,7 @@ static int call_nt_transact_notify_change(connection_struct *conn,
   change_notify_buf *cnbp;
   struct stat st;
 
-  fsp = GETFSP(setup,4);
+  fsp = file_fsp(setup,4);
 
   DEBUG(3,("call_nt_transact_notify_change\n"));
 
diff --git a/source3/smbd/pipes.c b/source3/smbd/pipes.c
index 84e31894a3..fed5c2bd17 100644
--- a/source3/smbd/pipes.c
+++ b/source3/smbd/pipes.c
@@ -138,8 +138,6 @@ int reply_pipe_read_and_X(char *inbuf,char *outbuf,int length,int bufsize)
 	DEBUG(3,("readX pnum=%04x min=%d max=%d nread=%d\n",
 		 p->pnum, smb_mincnt, smb_maxcnt, nread));
 
-	set_chain_p(p);
-
 	return chain_reply(inbuf,outbuf,length,bufsize);
 }
 /****************************************************************************
diff --git a/source3/smbd/reply.c b/source3/smbd/reply.c
index e62c0bd576..6b91d9d152 100644
--- a/source3/smbd/reply.c
+++ b/source3/smbd/reply.c
@@ -33,7 +33,6 @@ extern int Protocol;
 extern int DEBUGLEVEL;
 extern int max_send;
 extern int max_recv;
-extern files_struct *chain_fsp;
 extern char magic_char;
 extern BOOL case_sensitive;
 extern BOOL case_preserve;
@@ -1425,8 +1424,6 @@ int reply_open_and_X(connection_struct *conn, char *inbuf,char *outbuf,int lengt
   SSVAL(outbuf,smb_vwv8,rmode);
   SSVAL(outbuf,smb_vwv11,smb_action);
 
-  chain_fsp = fsp;
-
   return chain_reply(inbuf,outbuf,length,bufsize);
 }
 
@@ -1773,7 +1770,7 @@ int reply_readbraw(connection_struct *conn, char *inbuf, char *outbuf, int dum_s
     return -1;
   }
 
-  fsp = GETFSP(inbuf,smb_vwv0);
+  fsp = file_fsp(inbuf,smb_vwv0);
 
   startpos = IVAL(inbuf,smb_vwv1);
   maxcount = SVAL(inbuf,smb_vwv3);
@@ -1862,7 +1859,7 @@ int reply_lockread(connection_struct *conn, char *inbuf,char *outbuf, int dum_si
   uint32 startpos, numtoread;
   int eclass;
   uint32 ecode;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_READ(fsp);
@@ -1905,7 +1902,7 @@ int reply_read(connection_struct *conn, char *inbuf,char *outbuf, int dum_size,
   char *data;
   uint32 startpos;
   int outsize = 0;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_READ(fsp);
@@ -1945,7 +1942,7 @@ int reply_read(connection_struct *conn, char *inbuf,char *outbuf, int dum_size,
 ****************************************************************************/
 int reply_read_and_X(connection_struct *conn, char *inbuf,char *outbuf,int length,int bufsize)
 {
-  files_struct *fsp = GETFSP(inbuf,smb_vwv2);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv2);
   uint32 smb_offs = IVAL(inbuf,smb_vwv3);
   int smb_maxcnt = SVAL(inbuf,smb_vwv5);
   int smb_mincnt = SVAL(inbuf,smb_vwv6);
@@ -1979,8 +1976,6 @@ int reply_read_and_X(connection_struct *conn, char *inbuf,char *outbuf,int lengt
   DEBUG( 3, ( "readX fnum=%d min=%d max=%d nread=%d\n",
 	      fsp->fnum, smb_mincnt, smb_maxcnt, nread ) );
 
-  chain_fsp = fsp;
-
   return chain_reply(inbuf,outbuf,length,bufsize);
 }
 
@@ -1998,7 +1993,7 @@ int reply_writebraw(connection_struct *conn, char *inbuf,char *outbuf, int dum_s
   char *data=NULL;
   BOOL write_through;
   int tcount;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_WRITE(fsp);
@@ -2100,7 +2095,7 @@ int reply_writeunlock(connection_struct *conn, char *inbuf,char *outbuf, int dum
   uint32 numtowrite,startpos;
   int eclass;
   uint32 ecode;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_WRITE(fsp);
@@ -2153,7 +2148,7 @@ int reply_write(connection_struct *conn, char *inbuf,char *outbuf,int dum_size,i
   int outsize = 0;
   int startpos;
   char *data;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_WRITE(fsp);
@@ -2203,7 +2198,7 @@ int reply_write(connection_struct *conn, char *inbuf,char *outbuf,int dum_size,i
 ****************************************************************************/
 int reply_write_and_X(connection_struct *conn, char *inbuf,char *outbuf,int length,int bufsize)
 {
-  files_struct *fsp = GETFSP(inbuf,smb_vwv2);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv2);
   uint32 smb_offs = IVAL(inbuf,smb_vwv3);
   int smb_dsize = SVAL(inbuf,smb_vwv10);
   int smb_doff = SVAL(inbuf,smb_vwv11);
@@ -2246,8 +2241,6 @@ int reply_write_and_X(connection_struct *conn, char *inbuf,char *outbuf,int leng
   DEBUG(3,("writeX fnum=%d num=%d wrote=%d\n",
 	   fsp->fnum, smb_dsize, nwritten));
 
-  chain_fsp = fsp;
-
   if (lp_syncalways(SNUM(conn)) || write_through)
     sync_file(conn,fsp);
 
@@ -2264,7 +2257,7 @@ int reply_lseek(connection_struct *conn, char *inbuf,char *outbuf, int dum_size,
   int32 res= -1;
   int mode,umode;
   int outsize = 0;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_ERROR(fsp);
@@ -2300,7 +2293,7 @@ int reply_lseek(connection_struct *conn, char *inbuf,char *outbuf, int dum_size,
 int reply_flush(connection_struct *conn, char *inbuf,char *outbuf, int dum_size, int dum_buffsize)
 {
   int outsize = set_message(outbuf,0,0,True);
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   if (fsp) {
 	  CHECK_FSP(fsp,conn);
@@ -2349,7 +2342,7 @@ int reply_close(connection_struct *conn,
 		return reply_pipe_close(conn, inbuf,outbuf);
 	}
 
-	fsp = GETFSP(inbuf,smb_vwv0);
+	fsp = file_fsp(inbuf,smb_vwv0);
 
 	/*
 	 * We can only use CHECK_FSP if we know it's not a directory.
@@ -2406,7 +2399,7 @@ int reply_writeclose(connection_struct *conn,
 	int startpos;
 	char *data;
 	time_t mtime;
-	files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+	files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
 	CHECK_FSP(fsp,conn);
 	CHECK_WRITE(fsp);
@@ -2452,7 +2445,7 @@ int reply_lock(connection_struct *conn,
 	uint32 count,offset;
 	int eclass;
 	uint32 ecode;
-	files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+	files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
 	CHECK_FSP(fsp,conn);
 	CHECK_ERROR(fsp);
@@ -2479,7 +2472,7 @@ int reply_unlock(connection_struct *conn, char *inbuf,char *outbuf, int dum_size
   uint32 count,offset;
   int eclass;
   uint32 ecode;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_ERROR(fsp);
@@ -2629,7 +2622,7 @@ int reply_printclose(connection_struct *conn,
 		     char *inbuf,char *outbuf, int dum_size, int dum_buffsize)
 {
 	int outsize = set_message(outbuf,0,0,True);
-	files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+	files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
 	CHECK_FSP(fsp,conn);
 	CHECK_ERROR(fsp);
@@ -2724,7 +2717,7 @@ int reply_printwrite(connection_struct *conn, char *inbuf,char *outbuf, int dum_
   int numtowrite;
   int outsize = set_message(outbuf,0,0,True);
   char *data;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
   
   if (!CAN_PRINT(conn))
     return(ERROR(ERRDOS,ERRnoaccess));
@@ -3490,7 +3483,7 @@ int reply_setdir(connection_struct *conn, char *inbuf,char *outbuf, int dum_size
 ****************************************************************************/
 int reply_lockingX(connection_struct *conn, char *inbuf,char *outbuf,int length,int bufsize)
 {
-  files_struct *fsp = GETFSP(inbuf,smb_vwv2);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv2);
   unsigned char locktype = CVAL(inbuf,smb_vwv3);
 #if 0
   unsigned char oplocklevel = CVAL(inbuf,smb_vwv3+1);
@@ -3606,8 +3599,6 @@ dev = %x, inode = %x\n",
   DEBUG( 3, ( "lockingX fnum=%d type=%d num_locks=%d num_ulocks=%d\n",
 	fsp->fnum, (unsigned int)locktype, num_locks, num_ulocks ) );
 
-  chain_fsp = fsp;
-
   return chain_reply(inbuf,outbuf,length,bufsize);
 }
 
@@ -3625,7 +3616,7 @@ int reply_readbmpx(connection_struct *conn, char *inbuf,char *outbuf,int length,
   int max_per_packet;
   int tcount;
   int pad;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   /* this function doesn't seem to work - disable by default */
   if (!lp_readbmpx())
@@ -3692,7 +3683,7 @@ int reply_writebmpx(connection_struct *conn, char *inbuf,char *outbuf, int dum_s
   uint32 startpos;
   int tcount, write_through, smb_doff;
   char *data;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_WRITE(fsp);
@@ -3785,7 +3776,7 @@ int reply_writebs(connection_struct *conn, char *inbuf,char *outbuf, int dum_siz
   char *data;
   write_bmpx_struct *wbms;
   BOOL send_response = False; 
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   CHECK_FSP(fsp,conn);
   CHECK_WRITE(fsp);
@@ -3859,7 +3850,7 @@ int reply_setattrE(connection_struct *conn, char *inbuf,char *outbuf, int dum_si
 {
   struct utimbuf unix_times;
   int outsize = 0;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   outsize = set_message(outbuf,0,0,True);
 
@@ -3912,7 +3903,7 @@ int reply_getattrE(connection_struct *conn, char *inbuf,char *outbuf, int dum_si
   struct stat sbuf;
   int outsize = 0;
   int mode;
-  files_struct *fsp = GETFSP(inbuf,smb_vwv0);
+  files_struct *fsp = file_fsp(inbuf,smb_vwv0);
 
   outsize = set_message(outbuf,11,0,True);
 
diff --git a/source3/smbd/server.c b/source3/smbd/server.c
index e6117000a4..f160b590dc 100644
--- a/source3/smbd/server.c
+++ b/source3/smbd/server.c
@@ -81,9 +81,6 @@ int max_send = BUFFER_SIZE;
  */
 int max_recv = BUFFER_SIZE;
 
-/* a fsp to use when chaining */
-files_struct *chain_fsp = NULL;
-
 /* number of open connections */
 static int num_connections_open = 0;
 
@@ -4699,7 +4696,7 @@ int construct_reply(char *inbuf,char *outbuf,int size,int bufsize)
   smb_last_time = time(NULL);
 
   chain_size = 0;
-  chain_fsp = NULL;
+  file_chain_reset();
   reset_chain_p();
 
   if (msg_type != 0)
diff --git a/source3/smbd/trans2.c b/source3/smbd/trans2.c
index 72ad7ec12b..2789282771 100644
--- a/source3/smbd/trans2.c
+++ b/source3/smbd/trans2.c
@@ -32,7 +32,6 @@ extern int oplock_sock;
 extern int smb_read_error;
 extern fstring local_machine;
 extern int global_oplock_break;
-extern files_struct *chain_fsp;
 
 /****************************************************************************
   Send the required number of replies back.
@@ -1209,7 +1208,7 @@ static int call_trans2qfilepathinfo(connection_struct *conn,
   BOOL bad_path = False;
 
   if (tran_call == TRANSACT2_QFILEINFO) {
-    files_struct *fsp = GETFSP(params,0);
+    files_struct *fsp = file_fsp(params,0);
     info_level = SVAL(params,2);
 
     CHECK_FSP(fsp,conn);
@@ -1434,7 +1433,7 @@ static int call_trans2setfilepathinfo(connection_struct *conn,
     return(ERROR(ERRSRV,ERRaccess));
 
   if (tran_call == TRANSACT2_SETFILEINFO) {
-    files_struct *fsp = GETFSP(params,0);
+    files_struct *fsp = file_fsp(params,0);
     info_level = SVAL(params,2);    
 
     CHECK_FSP(fsp,conn);