X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdata%2Fvalue.c;h=9fcf1cbb9b8fa0a97cb4e75544a9a6892879ab68;hb=c3ac5a8af9c449072c7e872ca70a78c1755ae309;hp=2de3adbae440e32e54e856984056718c5ec0cccb;hpb=338fb2a2e84df6427a2fdee6769421f57d5666d8;p=pspp-builds.git

diff --git a/src/data/value.c b/src/data/value.c
index 2de3adba..9fcf1cbb 100644
--- a/src/data/value.c
+++ b/src/data/value.c
@@ -1,27 +1,26 @@
-/* PSPP - computes sample statistics.
+/* PSPP - a program for statistical analysis.
    Copyright (C) 1997-9, 2000 Free Software Foundation, Inc.
-   Written by Ben Pfaff <blp@gnu.org>.
 
-   This program is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public License as
-   published by the Free Software Foundation; either version 2 of the
-   License, or (at your option) any later version.
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
 
-   This program is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301, USA. */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
 #include <config.h>
-#include "value.h"
+#include <data/value.h>
 
+#include <data/val-type.h>
 #include <libpspp/hash.h>
 #include <libpspp/str.h>
+#include "variable.h"
 
 #include "xalloc.h"
 
@@ -33,13 +32,27 @@ value_dup (const union value *val, int width)
   return xmemdup (val, MAX (width, sizeof *val));
 }
 
+
+/* Create a value of specified width.
+   The caller is responsible for freeing the returned value. */
+union value *
+value_create (int width)
+{
+  return xnmalloc (value_cnt_from_width (width), sizeof (union value));
+}
+
+
 /* Compares A and B, which both have the given WIDTH, and returns
    a strcmp()-type result.
    Only the short string portion of longer strings are
    compared. */
 int
-compare_values (const union value *a, const union value *b, int width) 
+compare_values (const void *a_, const void *b_, const void *var_)
 {
+  const union value *a = a_;
+  const union value *b = b_;
+  const struct variable *var = var_;
+  int width = var_get_width (var);
   return (width == 0
           ? (a->f < b->f ? -1 : a->f > b->f)
           : memcmp (a->s, b->s, MIN (MAX_SHORT_STRING, width)));
@@ -47,10 +60,65 @@ compare_values (const union value *a, const union value *b, int width)
 
 /* Create a hash of V, which has the given WIDTH.
    Only the short string portion of a longer string is hashed. */
-unsigned 
-hash_value (const union value *v, int width)
+unsigned
+hash_value (const void *v_, const void *var_)
 {
+  const union value *v = v_;
+  const struct variable *var = var_;
+  int width = var_get_width (var);
   return (width == 0
           ? hsh_hash_double (v->f)
-          : hsh_hash_bytes (v->s, MIN (MAX_SHORT_STRING, width)));
+	  : hsh_hash_bytes (v->s, width));
+}
+
+
+/* Copies SRC to DST, given that they both contain data of the
+   given WIDTH. */
+void
+value_copy (union value *dst, const union value *src, int width)
+{
+  if (width == 0)
+    dst->f = src->f;
+  else
+    memcpy (dst->s, src->s, width);
+}
+
+/* Sets V to the system-missing value for data of the given
+   WIDTH. */
+void
+value_set_missing (union value *v, int width)
+{
+  if (width == 0)
+    v->f = SYSMIS;
+  else
+    memset (v->s, ' ', width);
+}
+
+/* Tests whether VALUE may be resized from OLD_WIDTH to
+   NEW_WIDTH, using the following rules that match those for
+   resizing missing values and value labels.  First, OLD_WIDTH
+   and NEW_WIDTH must be both numeric or both string.  Second, if
+   NEW_WIDTH is less than OLD_WIDTH, then the bytes that would be
+   trimmed off the right end of VALUE must be all spaces. */
+bool
+value_is_resizable (const union value *value, int old_width, int new_width)
+{
+  int i;
+
+  if (val_type_from_width (old_width) != val_type_from_width (new_width))
+    return false;
+  for (i = new_width; i < old_width; i++)
+    if (value->s[i] != ' ')
+      return false;
+  return true;
+}
+
+/* Resizes VALUE from OLD_WIDTH to NEW_WIDTH.  The arguments must
+   satisfy the rules specified above for value_is_resizable. */
+void
+value_resize (union value *value, int old_width, int new_width)
+{
+  assert (value_is_resizable (value, old_width, new_width));
+  if (new_width > old_width)
+    memset (&value->s[old_width], ' ', new_width - old_width);
 }