src/data/mrset.c

   1 /* PSPP - a program for statistical analysis.
   2    Copyright (C) 2010, 2011 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
  16
  17 #include <config.h>
  18
  19 #include "data/mrset.h"
  20
  21 #include <stdlib.h>
  22
  23 #include "data/dictionary.h"
  24 #include "data/identifier.h"
  25 #include "data/val-type.h"
  26 #include "data/variable.h"
  27 #include "libpspp/message.h"
  28
  29 #include "gl/xalloc.h"
  30
  31 #include "gettext.h"
  32 #define _(msgid) gettext (msgid)
  33
  34 /* Creates and returns a clone of OLD.  The caller is responsible for freeing
  35    the new multiple response set (using mrset_destroy()). */
  36 struct mrset *
  37 mrset_clone (const struct mrset *old)
  38 {
  39   struct mrset *new;
  40
  41   new = xmalloc (sizeof *new);
  42   new->name = xstrdup (old->name);
  43   new->label = xstrdup_if_nonnull (old->label);
  44   new->type = old->type;
  45   new->vars = xmemdup (old->vars, old->n_vars * sizeof *old->vars);
  46   new->n_vars = old->n_vars;
  47
  48   new->cat_source = old->cat_source;
  49   new->label_from_var_label = old->label_from_var_label;
  50   value_clone (&new->counted, &old->counted, old->width);
  51   new->width = old->width;
  52
  53   return new;
  54 }
  55
  56 /* Frees MRSET and the data that it contains. */
  57 void
  58 mrset_destroy (struct mrset *mrset)
  59 {
  60   if (mrset != NULL)
  61     {
  62       free (mrset->name);
  63       free (mrset->label);
  64       free (mrset->vars);
  65       value_destroy (&mrset->counted, mrset->width);
  66       free (mrset);
  67     }
  68 }
  69
  70 /* Checks whether the UTF-8 encoded NAME is a valid name for a multiple
  71    response set in a dictionary encoded in DICT_ENCODING.  Return NULL if it
  72    is, otherwise an error message that the caller must free(). */
  73 char * WARN_UNUSED_RESULT
  74 mrset_is_valid_name__ (const char *name, const char *dict_encoding)
  75 {
  76   return id_is_valid__ (name, dict_encoding, DC_SYSTEM);
  77 }
  78
  79 static bool
  80 error_to_bool (char *error)
  81 {
  82   if (error)
  83     {
  84       free (error);
  85       return false;
  86     }
  87   else
  88     return true;
  89 }
  90
  91 /* Returns true if the UTF-8 encoded NAME is a valid name for a multiple
  92    response set in a dictionary encoded in DICT_ENCODING, false otherwise. */
  93 bool
  94 mrset_is_valid_name (const char *name, const char *dict_encoding)
  95 {
  96   return error_to_bool (mrset_is_valid_name__ (name, dict_encoding));
  97 }
  98
  99 /* Checks various constraints on MRSET:
 100
 101    - MRSET's name begins with '$' and is valid as an identifier in DICT.
 102
 103    - MRSET has a valid type.
 104
 105    - MRSET has at least 2 variables.
 106
 107    - All of MRSET's variables are in DICT.
 108
 109    - All of MRSET's variables are the same type (numeric or string).
 110
 111    - If MRSET is a multiple dichotomy set, its counted value has the same type
 112      as and is no wider than its narrowest variable.
 113
 114    Returns true if all the constraints are satisfied, otherwise false. */
 115 bool
 116 mrset_ok (const struct mrset *mrset, const struct dictionary *dict)
 117 {
 118   enum val_type type;
 119   size_t i;
 120
 121   if (mrset->name == NULL
 122       || !mrset_is_valid_name (mrset->name, dict_get_encoding (dict))
 123       || (mrset->type != MRSET_MD && mrset->type != MRSET_MC)
 124       || mrset->vars == NULL
 125       || mrset->n_vars < 2)
 126     return false;
 127
 128   type = var_get_type (mrset->vars[0]);
 129   if (mrset->type == MRSET_MD && type != val_type_from_width (mrset->width))
 130     return false;
 131   for (i = 0; i < mrset->n_vars; i++)
 132     if (!dict_contains_var (dict, mrset->vars[i])
 133         || type != var_get_type (mrset->vars[i])
 134         || (mrset->type == MRSET_MD
 135             && mrset->width > var_get_width (mrset->vars[i])))
 136       return false;
 137
 138   return true;
 139 }