damn, I had implicitly assumed signed characters when writing the

rolling checksum code. The result is that rsync worked much more
slowly when going between two machines where one of the machines uses
signed and the other unsigned chars. The rolling checksum rarely
matched so effectively a copy was done in many cases. The data always
came through correctly so no file corruption occurred but it's pretty
pointless using rsync if it doesn't speed things up!
I've now made the sign of the chars explicit

diff --git a/checksum.c b/checksum.c
index 201583633cfd7f73e596afe7966d40277b8b73d9..7b8035cc95489227130288f1be8ac8119587fb9f 100644 (file)
--- a/checksum.c
+++ b/checksum.c
@@ -30,10 +30,11 @@ extern int remote_version;
   a simple 32 bit checksum that can be upadted from either end
   (inspired by Mark Adler's Adler-32 checksum)
   */
-uint32 get_checksum1(char *buf,int len)
+uint32 get_checksum1(char *buf1,int len)
 {
     int i;
     uint32 s1, s2;
+    signed char *buf = (signed char *)buf1;
 
     s1 = s2 = 0;
     for (i = 0; i < (len-4); i+=4) {

diff --git a/match.c b/match.c
index 591558fddf1c6e84eb95414d899e648b51424f90..a353c83b82f869d1f591c0e4c39560b6741ef57d 100644 (file)
--- a/match.c
+++ b/match.c
@@ -130,16 +130,16 @@ static void hash_search(int f,struct sum_struct *s,
   int end;
   char sum2[SUM_LENGTH];
   uint32 s1, s2, sum; 
-  char *map;
+  signed char *map;
 
   if (verbose > 2)
     fprintf(FERROR,"hash search b=%d len=%d\n",s->n,(int)len);
 
   k = MIN(len, s->n);
 
-  map = map_ptr(buf,0,k);
+  map = (signed char *)map_ptr(buf,0,k);
 
-  sum = get_checksum1(map, k);
+  sum = get_checksum1((char *)map, k);
   s1 = sum & 0xFFFF;
   s2 = sum >> 16;
   if (verbose > 3)
@@ -175,16 +175,16 @@ static void hash_search(int f,struct sum_struct *s,
 
          if (!done_csum2) {
            int l = MIN(s->n,len-offset);
-           map = map_ptr(buf,offset,l);
-           get_checksum2(map,l,sum2);
+           map = (signed char *)map_ptr(buf,offset,l);
+           get_checksum2((char *)map,l,sum2);
            done_csum2 = 1;
          }
          if (memcmp(sum2,s->sums[i].sum2,csum_length) == 0) {
            matched(f,s,buf,len,offset,i);
            offset += s->sums[i].len - 1;
            k = MIN((len-offset), s->n);
-           map = map_ptr(buf,offset,k);
-           sum = get_checksum1(map, k);
+           map = (signed char *)map_ptr(buf,offset,k);
+           sum = get_checksum1((char *)map, k);
            s1 = sum & 0xFFFF;
            s2 = sum >> 16;
            ++matches;
@@ -198,7 +198,7 @@ static void hash_search(int f,struct sum_struct *s,
     }
 
     /* Trim off the first byte from the checksum */
-    map = map_ptr(buf,offset,k+1);
+    map = (signed char *)map_ptr(buf,offset,k+1);
     s1 -= map[0] + CHAR_OFFSET;
     s2 -= k * (map[0]+CHAR_OFFSET);