Make sure our use of idev_find() hashtable is right

while also supporting older rsyncs that send dev == 0.

2 files changed, 14 insertions, 11 deletions

diff --git a/flist.c b/flist.c
index 09824770..253dbe0a 100644
--- a/flist.c
+++ b/flist.c
@@ -118,7 +118,7 @@ int flist_eof = 0; /* all the file-lists are now known */
  * will survive just long enough to be used by send_file_entry(). */
 static dev_t tmp_rdev;
 #ifdef SUPPORT_HARD_LINKS
-static int64 tmp_dev, tmp_ino;
+static int64 tmp_dev = -1, tmp_ino;
 #endif
 static char tmp_sum[MAX_DIGEST_LEN];
 
@@ -480,7 +480,7 @@ static void send_file_entry(int f, const char *fname, struct file_struct *file,
 		modtime = file->modtime;
 
 #ifdef SUPPORT_HARD_LINKS
-	if (tmp_dev != 0) {
+	if (tmp_dev != -1) {
 		if (protocol_version >= 30) {
 			struct ht_int64_node *np = idev_find(tmp_dev, tmp_ino);
 			first_hlink_ndx = (int32)(long)np->data - 1;
@@ -598,15 +598,17 @@ static void send_file_entry(int f, const char *fname, struct file_struct *file,
 #endif
 
 #ifdef SUPPORT_HARD_LINKS
-	if (tmp_dev != 0 && protocol_version < 30) {
+	if (tmp_dev != -1 && protocol_version < 30) {
+		/* Older protocols expect the dev number to be transmitted
+		 * 1-incremented so that it is never zero. */
 		if (protocol_version < 26) {
 			/* 32-bit dev_t and ino_t */
-			write_int(f, (int32)dev);
+			write_int(f, (int32)(dev+1));
 			write_int(f, (int32)tmp_ino);
 		} else {
 			/* 64-bit dev_t and ino_t */
 			if (!(xflags & XMIT_SAME_DEV_pre30))
-				write_longint(f, dev);
+				write_longint(f, dev+1);
 			write_longint(f, tmp_ino);
 		}
 	}
@@ -1259,10 +1261,10 @@ struct file_struct *make_file(const char *fname, struct file_list *flist,
 		if (protocol_version >= 28
 		 ? (!S_ISDIR(st.st_mode) && st.st_nlink > 1)
 		 : S_ISREG(st.st_mode)) {
-			tmp_dev = (int64)st.st_dev + 1;
+			tmp_dev = (int64)st.st_dev;
 			tmp_ino = (int64)st.st_ino;
 		} else
-			tmp_dev = 0;
+			tmp_dev = -1;
 	}
 #endif
 
diff --git a/hlink.c b/hlink.c
index 5ab9bb86..0c4ab4d6 100644
--- a/hlink.c
+++ b/hlink.c
@@ -57,7 +57,7 @@ static struct file_list *hlink_flist;
 void init_hard_links(void)
 {
 	if (am_sender || protocol_version < 30)
-		dev_tbl = hashtable_create(16, SIZEOF_INT64 == 8);
+		dev_tbl = hashtable_create(16, 1);
 	else if (inc_recurse)
 		prior_hlinks = hashtable_create(1024, 0);
 }
@@ -67,11 +67,12 @@ struct ht_int64_node *idev_find(int64 dev, int64 ino)
 	static struct ht_int64_node *dev_node = NULL;
 	struct hashtable *tbl;
 
-	if (!dev_node || dev_node->key != dev) {
+	/* Note that some OSes have a dev == 0, so increment to avoid storing a 0. */
+	if (!dev_node || dev_node->key != dev+1) {
 		/* We keep a separate hash table of inodes for every device. */
-		dev_node = hashtable_find(dev_tbl, dev, 1);
+		dev_node = hashtable_find(dev_tbl, dev+1, 1);
 		if (!(tbl = dev_node->data))
-			tbl = dev_node->data = hashtable_create(512, SIZEOF_INT64 == 8);
+			tbl = dev_node->data = hashtable_create(512, 1);
 	} else
 		tbl = dev_node->data;