- Do less seeking when writing a sparse file.

[rsync/rsync.git] / fileio.c

diff --git a/fileio.c b/fileio.c
index 432336c..303a384 100644 (file)
--- a/fileio.c
+++ b/fileio.c
@@ -28,47 +28,55 @@
 extern int sparse_files;
 
 static char last_byte;
-static int last_sparse;
+static size_t sparse_seek = 0;
 
 int sparse_end(int f)
 {
-       if (last_sparse) {
-               do_lseek(f,-1,SEEK_CUR);
-               return (write(f,&last_byte,1) == 1 ? 0 : -1);
-       }
-       last_sparse = 0;
-       return 0;
+       int ret;
+
+       if (!sparse_seek)
+               return 0;
+
+       do_lseek(f, sparse_seek-1, SEEK_CUR);
+       sparse_seek = 0;
+
+       do {
+               ret = write(f, "", 1);
+       } while (ret < 0 && errno == EINTR);
+
+       return ret <= 0 ? -1 : 0;
 }
 
 
-static int write_sparse(int f,char *buf,size_t len)
+static int write_sparse(int f, char *buf, size_t len)
 {
-       size_t l1=0, l2=0;
+       size_t l1 = 0, l2 = 0;
        int ret;
 
        for (l1 = 0; l1 < len && buf[l1] == 0; l1++) {}
        for (l2 = 0; l2 < len-l1 && buf[len-(l2+1)] == 0; l2++) {}
 
+       /* XXX Riddle me this: why does this function SLOW DOWN when I
+        * remove the following (unneeded) line?? Core Duo weirdness? */
        last_byte = buf[len-1];
 
-       if (l1 == len || l2 > 0)
-               last_sparse=1;
-
-       if (l1 > 0) {
-               do_lseek(f,l1,SEEK_CUR);
-       }
+       sparse_seek += l1;
 
        if (l1 == len)
                return len;
 
-       ret = write(f, buf + l1, len - (l1+l2));
-       if (ret == -1 || ret == 0)
+       if (sparse_seek)
+               do_lseek(f, sparse_seek, SEEK_CUR);
+       sparse_seek = l2;
+
+       while ((ret = write(f, buf + l1, len - (l1+l2))) <= 0) {
+               if (ret < 0 && errno == EINTR)
+                       continue;
                return ret;
-       else if (ret != (int) (len - (l1+l2)))
-               return (l1+ret);
+       }
 
-       if (l2 > 0)
-               do_lseek(f,l2,SEEK_CUR);
+       if (ret != (int)(len - (l1+l2)))
+               return l1+ret;
 
        return len;
 }