- Never allocate a useless sum array for a non-regular flist item.

- Don't transmit the sum array for non-regular files (p28 onward).
- Tweaked a couple comments.

diff --git a/flist.c b/flist.c
index f1b054f..c926ffd 100644 (file)
--- a/flist.c
+++ b/flist.c
@@ -70,6 +70,7 @@ extern struct exclude_struct **local_exclude_list;
 int io_error;
 
 static struct file_struct null_file;
+static char empty_sum[MD4_SUM_LENGTH];
 
 static void clean_flist(struct file_list *flist, int strip_root, int no_dups);
 
@@ -357,7 +358,7 @@ static void send_file_entry(struct file_struct *file, int f,
        unsigned short flags;
        static time_t modtime;
        static mode_t mode;
-       static DEV64_T rdev;    /* just high bytes after p28 */
+       static DEV64_T rdev;    /* just high bytes in p28 onward */
        static uid_t uid;
        static gid_t gid;
        static DEV64_T dev;
@@ -500,11 +501,10 @@ static void send_file_entry(struct file_struct *file, int f,
        }
 #endif
 
-       if (always_checksum) {
-               if (protocol_version < 21)
-                       write_buf(f, file->sum, 2);
-               else
-                       write_buf(f, file->sum, MD4_SUM_LENGTH);
+       if (always_checksum && (protocol_version < 28 || S_ISREG(mode))) {
+               char *sum = file->sum? file->sum : empty_sum;
+               write_buf(f, sum, protocol_version < 21? 2
+                                               : MD4_SUM_LENGTH);
        }
 
        strlcpy(lastname, fname, MAXPATHLEN);
@@ -520,7 +520,7 @@ static void receive_file_entry(struct file_struct **fptr,
 {
        static time_t modtime;
        static mode_t mode;
-       static DEV64_T rdev;    /* just high bytes after p28 */
+       static DEV64_T rdev;    /* just high bytes in p28 onward */
        static uid_t uid;
        static gid_t gid;
        static DEV64_T dev;
@@ -649,19 +649,26 @@ static void receive_file_entry(struct file_struct **fptr,
 #endif
 
        if (always_checksum) {
-               file->sum = new_array(char, MD4_SUM_LENGTH);
-               if (!file->sum)
-                       out_of_memory("md4 sum");
-               if (protocol_version < 21)
-                       read_buf(f, file->sum, 2);
-               else
-                       read_buf(f, file->sum, MD4_SUM_LENGTH);
+               char tmpsum[MD4_SUM_LENGTH], *sum;
+               if (S_ISREG(mode)) {
+                       sum = file->sum = new_array(char, MD4_SUM_LENGTH);
+                       if (!sum)
+                               out_of_memory("md4 sum");
+               } else if (protocol_version < 28) {
+                       /* Prior to 28, we get a useless set of nulls. */
+                       sum = tmpsum;
+               } else
+                       sum = NULL;
+               if (sum) {
+                       read_buf(f, sum, protocol_version < 21? 2
+                                               : MD4_SUM_LENGTH);
+               }
        }
 
        if (!preserve_perms) {
                extern int orig_umask;
                /* set an appropriate set of permissions based on original
-                  permissions and umask. This emulates what GNU cp does */
+                * permissions and umask. This emulates what GNU cp does */
                file->mode &= ~orig_umask;
        }
 }
@@ -817,18 +824,11 @@ struct file_struct *make_file(char *fname, struct string_area **ap,
                file->link = STRDUP(ap, linkbuf);
 #endif
 
-       if (always_checksum) {
-               file->sum = (char *) MALLOC(ap, MD4_SUM_LENGTH);
+       if (always_checksum && S_ISREG(st.st_mode)) {
+               file->sum = (char*)MALLOC(ap, MD4_SUM_LENGTH);
                if (!file->sum)
                        out_of_memory("md4 sum");
-               /* drat. we have to provide a null checksum for non-regular
-                  files in order to be compatible with earlier versions
-                  of rsync */
-               if (S_ISREG(st.st_mode)) {
-                       file_checksum(fname, file->sum, st.st_size);
-               } else {
-                       memset(file->sum, 0, MD4_SUM_LENGTH);
-               }
+               file_checksum(fname, file->sum, st.st_size);
        }
 
        if (flist_dir) {