X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdata%2Ffastfile.c;h=7fa6eb85916e1befcbdb84c81c1c13abbcc20c15;hb=f49ed94900625697d344071290cf2360293c27e3;hp=9cdba1567648b002c7848b057ba431be88464ff4;hpb=57b436a22d9ae0e395fb2e3ce101c2b5c2e6939e;p=pspp

diff --git a/src/data/fastfile.c b/src/data/fastfile.c
index 9cdba15676..7fa6eb8591 100644
--- a/src/data/fastfile.c
+++ b/src/data/fastfile.c
@@ -1,6 +1,5 @@
 /* PSPP - computes sample statistics.
-   Copyright (C) 2004, 2006 Free Software Foundation, Inc.
-   Written by Ben Pfaff <blp@gnu.org>.
+   Copyright (C) 2004, 2006, 2007 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -18,9 +17,11 @@
    02110-1301, USA. */
 
 #include <config.h>
+
 #include "casefile.h"
 #include "casefile-private.h"
 #include "fastfile.h"
+
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -28,16 +29,19 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+
+#include <data/case.h>
+#include <data/make-file.h>
+#include <data/settings.h>
+#include <data/variable.h>
 #include <libpspp/alloc.h>
-#include "case.h"
 #include <libpspp/compiler.h>
 #include <libpspp/message.h>
+#include <libpspp/misc.h>
+#include <libpspp/str.h>
+
 #include "full-read.h"
 #include "full-write.h"
-#include <libpspp/misc.h>
-#include "make-file.h"
-#include "settings.h"
-#include "variable.h"
 
 #include "gettext.h"
 #define _(msgid) gettext (msgid)
@@ -86,8 +90,7 @@
           also read with casereaders in this phase, but the
           ability to create new casereaders is curtailed.
 
-          In this phase, casereaders could still be cloned (once
-          we eventually implement cloning).
+          In this phase, casereaders could still be cloned.
 
           To transition from phase 1 or 2 to phase 3 and create a
           casereader, call casefile_get_destructive_reader().
@@ -287,6 +290,44 @@ fastfile_get_reader (const struct casefile *cf_)
   return reader;
 }
 
+
+/* Creates a copy of the casereader CR, and returns it */
+static struct casereader *
+fastfilereader_clone (const struct casereader *cr)
+{
+  const struct fastfilereader *ffr = (const struct fastfilereader *) cr ;
+  struct fastfilereader *new_ffr = xzalloc (sizeof *new_ffr);
+
+  struct casereader *new_reader = (struct casereader *) new_ffr;
+
+  struct casefile *cf =  casereader_get_casefile (cr);
+  struct fastfile *ff = (struct fastfile *) cf;
+
+  assert (!cf->being_destroyed);
+
+  /* Flush the buffer to disk if it's not empty. */
+  if (ff->mode == WRITE && ff->storage == DISK)
+    flush_buffer (ff);
+
+  ff->mode = READ;
+
+  casereader_register (cf, new_reader, &class_reader);
+
+  new_ffr->case_idx = ffr->case_idx ;
+  new_reader->destructive = cr->destructive;
+  new_ffr->fd = ffr->fd ;
+  new_ffr->buffer = ffr->buffer ;
+  new_ffr->buffer_pos = ffr->buffer_pos;
+
+  if (ff->storage == DISK)
+    reader_open_file (new_ffr);
+
+  return new_reader;
+}
+
+
+
+
 /* Returns the number of `union value's in a case for CF. */
 static size_t
 fastfile_get_value_cnt (const struct casefile *cf)
@@ -748,4 +789,5 @@ static const struct class_casereader class_reader =
     fastfilereader_get_next_case,
     fastfilereader_cnum,
     fastfilereader_destroy,
+    fastfilereader_clone,
   };