X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/fb01d1fb07f6efd3752ff895fe8a77e26a2b2055..886df221c1ce1660a2b6cd274b13952b482fe5bf:/match.c

diff --git a/match.c b/match.c
index a3659fc6..0d4cfeb1 100644
--- a/match.c
+++ b/match.c
@@ -23,8 +23,10 @@
 
 extern int checksum_seed;
 extern int append_mode;
+extern int checksum_len;
 
 int updating_basis_file;
+char sender_file_sum[MAX_DIGEST_LEN];
 
 static int false_alarms;
 static int hash_hits;
@@ -327,9 +329,6 @@ static void hash_search(int f,struct sum_struct *s,
  **/
 void match_sums(int f, struct sum_struct *s, struct map_struct *buf, OFF_T len)
 {
-	char file_sum[MAX_DIGEST_LEN];
-	int sum_len;
-
 	last_match = 0;
 	false_alarms = 0;
 	hash_hits = 0;
@@ -377,18 +376,28 @@ void match_sums(int f, struct sum_struct *s, struct map_struct *buf, OFF_T len)
 		matched(f, s, buf, len, -1);
 	}
 
-	sum_len = sum_end(file_sum);
-	/* If we had a read error, send a bad checksum. */
-	if (buf && buf->status != 0)
-		file_sum[0]++;
+	if (sum_end(sender_file_sum) != checksum_len)
+		overflow_exit("checksum_len"); /* Impossible... */
+
+	/* If we had a read error, send a bad checksum.  We use all bits
+	 * off as long as the checksum doesn't happen to be that, in
+	 * which case we turn the last 0 bit into a 1. */
+	if (buf && buf->status != 0) {
+		int i;
+		for (i = 0; i < checksum_len && sender_file_sum[i] == 0; i++) {}
+		memset(sender_file_sum, 0, checksum_len);
+		if (i == checksum_len)
+			sender_file_sum[i-1]++;
+	}
 
 	if (DEBUG_GTE(CHKSUM, 2))
 		rprintf(FINFO,"sending file_sum\n");
-	write_buf(f, file_sum, sum_len);
+	write_buf(f, sender_file_sum, checksum_len);
 
-	if (DEBUG_GTE(CHKSUM, 2))
+	if (DEBUG_GTE(CHKSUM, 2)) {
 		rprintf(FINFO, "false_alarms=%d hash_hits=%d matches=%d\n",
 			false_alarms, hash_hits, matches);
+	}
 
 	total_hash_hits += hash_hits;
 	total_false_alarms += false_alarms;