If we get less data than expected from a read() in map_ptr(), we

[rsync/rsync.git] / fileio.c

diff --git a/fileio.c b/fileio.c
index 45366f5..1806209 100644 (file)
--- a/fileio.c
+++ b/fileio.c
@@ -22,6 +22,10 @@
   */
 #include "rsync.h"
 
+#ifndef ENODATA
+#define ENODATA EAGAIN
+#endif
+
 extern int sparse_files;
 
 static char last_byte;
@@ -217,34 +221,35 @@ char *map_ptr(struct map_struct *map, OFF_T offset, int32 len)
                rprintf(FERROR, "invalid read_size of %ld in map_ptr\n",
                        (long)read_size);
                exit_cleanup(RERR_FILEIO);
-       } else {
-               if (map->p_fd_offset != read_start) {
-                       OFF_T ret = do_lseek(map->fd, read_start, SEEK_SET);
-                       if (ret != read_start) {
-                               rsyserr(FERROR, errno,
-                                       "lseek returned %.0f, not %.0f",
-                                       (double)ret, (double)read_start);
-                               exit_cleanup(RERR_FILEIO);
-                       }
-                       map->p_fd_offset = read_start;
-               }
+       }
 
-               if ((nread=read(map->fd,map->p + read_offset,read_size)) != read_size) {
-                       if (nread < 0) {
-                               nread = 0;
-                               if (!map->status)
-                                       map->status = errno;
-                       }
-                       /* the best we can do is zero the buffer - the file
-                          has changed mid transfer! */
-                       memset(map->p+read_offset+nread, 0, read_size - nread);
+       if (map->p_fd_offset != read_start) {
+               OFF_T ret = do_lseek(map->fd, read_start, SEEK_SET);
+               if (ret != read_start) {
+                       rsyserr(FERROR, errno, "lseek returned %.0f, not %.0f",
+                               (double)ret, (double)read_start);
+                       exit_cleanup(RERR_FILEIO);
                }
-               map->p_fd_offset += nread;
+               map->p_fd_offset = read_start;
        }
-
+       map->p_fd_offset += read_size;
        map->p_offset = window_start;
        map->p_len = window_size;
 
+       while (read_size > 0) {
+               nread = read(map->fd, map->p + read_offset, read_size);
+               if (nread <= 0) {
+                       if (!map->status)
+                               map->status = nread ? errno : ENODATA;
+                       /* The best we can do is zero the buffer -- the file
+                        * has changed mid transfer! */
+                       memset(map->p + read_offset, 0, read_size);
+                       break;
+               }
+               read_offset += nread;
+               read_size -= nread;
+       }
+
        return map->p;
 }