Change sending/receiving/storing of the rdev value for special files.

Since the value is not needed, protocol 31 no longer sends it, while
older protocols are optimized so the sender just sends a valid rdev
value as efficiently as possible.  The receiver no longer caches an
rdev value for special files, and the generator will always pass a 0
rdev value to do_mknod() for special files. Fixes bug #6280.

1 files changed, 21 insertions, 11 deletions

diff --git a/flist.c b/flist.c
index d7a70a61..2af7e88b 100644
--- a/flist.c
+++ b/flist.c
@@ -442,8 +442,7 @@ static void send_file_entry(int f, const char *fname, struct file_struct *file,
 	else
 		mode = file->mode;
 
-	if ((preserve_devices && IS_DEVICE(mode))
-	 || (preserve_specials && IS_SPECIAL(mode))) {
+	if (preserve_devices && IS_DEVICE(mode)) {
 		if (protocol_version < 28) {
 			if (tmp_rdev == rdev)
 				xflags |= XMIT_SAME_RDEV_pre28;
@@ -458,6 +457,17 @@ static void send_file_entry(int f, const char *fname, struct file_struct *file,
 			if (protocol_version < 30 && (uint32)minor(rdev) <= 0xFFu)
 				xflags |= XMIT_RDEV_MINOR_8_pre30;
 		}
+	} else if (preserve_specials && IS_SPECIAL(mode) && protocol_version < 31) {
+		/* Special files don't need an rdev number, so just make
+		 * the historical transmission of the value efficient. */
+		if (protocol_version < 28)
+			xflags |= XMIT_SAME_RDEV_pre28;
+		else {
+			rdev = MAKEDEV(major(rdev), 0);
+			xflags |= XMIT_SAME_RDEV_MAJOR;
+			if (protocol_version < 30)
+				xflags |= XMIT_RDEV_MINOR_8_pre30;
+		}
 	} else if (protocol_version < 28)
 		rdev = MAKEDEV(0, 0);
 	if (!preserve_uid || ((uid_t)F_OWNER(file) == uid && *lastname))
@@ -593,7 +603,7 @@ static void send_file_entry(int f, const char *fname, struct file_struct *file,
 		}
 	}
 	if ((preserve_devices && IS_DEVICE(mode))
-	 || (preserve_specials && IS_SPECIAL(mode))) {
+	 || (preserve_specials && IS_SPECIAL(mode) && protocol_version < 31)) {
 		if (protocol_version < 28) {
 			if (!(xflags & XMIT_SAME_RDEV_pre28))
 				write_int(f, (int)rdev);
@@ -762,8 +772,7 @@ static struct file_struct *recv_file_entry(struct file_list *flist,
 				uid = F_OWNER(first);
 			if (preserve_gid)
 				gid = F_GROUP(first);
-			if ((preserve_devices && IS_DEVICE(mode))
-			 || (preserve_specials && IS_SPECIAL(mode))) {
+			if (preserve_devices && IS_DEVICE(mode)) {
 				uint32 *devp = F_RDEV_P(first);
 				rdev = MAKEDEV(DEV_MAJOR(devp), DEV_MINOR(devp));
 				extra_len += DEV_EXTRA_CNT * EXTRA_LEN;
@@ -822,7 +831,7 @@ static struct file_struct *recv_file_entry(struct file_list *flist,
 	}
 
 	if ((preserve_devices && IS_DEVICE(mode))
-	 || (preserve_specials && IS_SPECIAL(mode))) {
+	 || (preserve_specials && IS_SPECIAL(mode) && protocol_version < 31)) {
 		if (protocol_version < 28) {
 			if (!(xflags & XMIT_SAME_RDEV_pre28))
 				rdev = (dev_t)read_int(f);
@@ -838,7 +847,8 @@ static struct file_struct *recv_file_entry(struct file_list *flist,
 				rdev_minor = read_int(f);
 			rdev = MAKEDEV(rdev_major, rdev_minor);
 		}
-		extra_len += DEV_EXTRA_CNT * EXTRA_LEN;
+		if (IS_DEVICE(mode))
+			extra_len += DEV_EXTRA_CNT * EXTRA_LEN;
 		file_length = 0;
 	} else if (protocol_version < 28)
 		rdev = MAKEDEV(0, 0);
@@ -979,8 +989,7 @@ static struct file_struct *recv_file_entry(struct file_list *flist,
 		}
 	}
 
-	if ((preserve_devices && IS_DEVICE(mode))
-	 || (preserve_specials && IS_SPECIAL(mode))) {
+	if (preserve_devices && IS_DEVICE(mode)) {
 		uint32 *devp = F_RDEV_P(file);
 		DEV_MAJOR(devp) = major(rdev);
 		DEV_MINOR(devp) = minor(rdev);
@@ -1307,10 +1316,11 @@ struct file_struct *make_file(const char *fname, struct file_list *flist,
 #endif
 
 #ifdef HAVE_STRUCT_STAT_ST_RDEV
-	if (IS_DEVICE(st.st_mode) || IS_SPECIAL(st.st_mode)) {
+	if (IS_DEVICE(st.st_mode)) {
 		tmp_rdev = st.st_rdev;
 		st.st_size = 0;
-	}
+	} else if (IS_SPECIAL(st.st_mode))
+		st.st_size = 0;
 #endif
 
 	file->flags = flags;