[VAR_NAME_LEN 01/17] dict: Make dict_make_unique_var_name() return an allocated string.

[Ben Pfaff]

---
 src/data/dictionary.c                |   52 +++++++++++++++++-----------------
 src/data/dictionary.h                |    7 ++--
 src/data/gnumeric-reader.c           |   13 ++------
 src/data/psql-reader.c               |   13 +++-----
 src/ui/gui/text-data-import-dialog.c |   25 ++++++++--------
 5 files changed, 51 insertions(+), 59 deletions(-)

diff --git a/src/data/dictionary.c b/src/data/dictionary.c
index 0ca9f9e..2ad94ca 100644
--- a/src/data/dictionary.c
+++ b/src/data/dictionary.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 1997-9, 2000, 2006, 2007, 2009, 2010 Free Software 
Foundation, Inc.
+   Copyright (C) 1997-9, 2000, 2006, 2007, 2009, 2010, 2011 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 published by
@@ -842,10 +842,10 @@ var_name_is_insertable (const struct dictionary *dict, 
const char *name)
           && lex_id_to_token (ss_cstr (name)) == T_ID);
 }
 
-static bool
-make_hinted_name (const struct dictionary *dict, const char *hint,
-                  char name[VAR_NAME_LEN + 1])
+static char *
+make_hinted_name (const struct dictionary *dict, const char *hint)
 {
+  char name[VAR_NAME_LEN + 1];
   bool dropped = false;
   char *cp;
 
@@ -874,7 +874,7 @@ make_hinted_name (const struct dictionary *dict, const char 
*hint,
       unsigned long int i;
 
       if (var_name_is_insertable (dict, name))
-        return true;
+        return xstrdup (name);
 
       for (i = 0; i < ULONG_MAX; i++)
         {
@@ -889,16 +889,15 @@ make_hinted_name (const struct dictionary *dict, const 
char *hint,
           strcpy (&name[ofs], suffix);
 
           if (var_name_is_insertable (dict, name))
-            return true;
+            return xstrdup (name);
         }
     }
 
-  return false;
+  return NULL;
 }
 
-static bool
-make_numeric_name (const struct dictionary *dict, unsigned long int *num_start,
-                   char name[VAR_NAME_LEN + 1])
+static char *
+make_numeric_name (const struct dictionary *dict, unsigned long int *num_start)
 {
   unsigned long int number;
 
@@ -906,27 +905,24 @@ make_numeric_name (const struct dictionary *dict, 
unsigned long int *num_start,
        number < ULONG_MAX;
        number++)
     {
+      char name[3 + INT_STRLEN_BOUND (number) + 1];
+
       sprintf (name, "VAR%03lu", number);
       if (dict_lookup_var (dict, name) == NULL)
         {
           if (num_start != NULL)
             *num_start = number + 1;
-          return true;
+          return xstrdup (name);
         }
     }
 
-  if (num_start != NULL)
-    *num_start = ULONG_MAX;
-  return false;
+  NOT_REACHED ();
 }
 
 
-/* Attempts to devise a variable name unique within DICT.
-   Returns true if successful, in which case the new variable
-   name is stored into NAME.  Returns false if all names that can
-   be generated have already been taken.  (Returning false is
-   quite unlikely: at least ULONG_MAX unique names can be
-   generated.)
+/* Devises and returns a variable name unique within DICT.  The variable name
+   is owned by the caller, which must free it with free() when it is no longer
+   needed.
 
    HINT, if it is non-null, is used as a suggestion that will be
    modified for suitability as a variable name and for
@@ -937,14 +933,18 @@ make_numeric_name (const struct dictionary *dict, 
unsigned long int *num_start,
    value is used.  If NUM_START is non-null, then its value is
    used as the minimum numeric value to check, and it is updated
    to the next value to be checked.
-   */
-bool
+*/
+char *
 dict_make_unique_var_name (const struct dictionary *dict, const char *hint,
-                           unsigned long int *num_start,
-                           char name[VAR_NAME_LEN + 1])
+                           unsigned long int *num_start)
 {
-  return ((hint != NULL && make_hinted_name (dict, hint, name))
-          || make_numeric_name (dict, num_start, name));
+  if (hint != NULL)
+    {
+      char *hinted_name = make_hinted_name (dict, hint);
+      if (hinted_name != NULL)
+        return hinted_name;
+    }
+  return make_numeric_name (dict, num_start);
 }
 
 /* Returns the weighting variable in dictionary D, or a null
diff --git a/src/data/dictionary.h b/src/data/dictionary.h
index 96529a1..3455a74 100644
--- a/src/data/dictionary.h
+++ b/src/data/dictionary.h
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2004, 2007, 2009, 2010 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2007, 2009, 2010, 2011 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 published by
@@ -84,9 +84,8 @@ void dict_rename_var (struct dictionary *, struct variable *, 
const char *);
 bool dict_rename_vars (struct dictionary *,
                        struct variable **, char **new_names,
                        size_t count, char **err_name);
-bool dict_make_unique_var_name (const struct dictionary *, const char *hint,
-                                unsigned long int *num_start,
-                                char name[]);
+char *dict_make_unique_var_name (const struct dictionary *, const char *hint,
+                                 unsigned long int *num_start);
 
 /* Weight variable. */
 double dict_get_case_weight (const struct dictionary *,
diff --git a/src/data/gnumeric-reader.c b/src/data/gnumeric-reader.c
index 64b29b7..9772d82 100644
--- a/src/data/gnumeric-reader.c
+++ b/src/data/gnumeric-reader.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2007, 2009, 2010 Free Software Foundation, Inc.
+   Copyright (C) 2007, 2009, 2010, 2011 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 published by
@@ -504,21 +504,16 @@ gnumeric_open_reader (struct gnumeric_read_info *gri, 
struct dictionary **dict)
 
   for (i = 0 ; i < n_var_specs ; ++i )
     {
-      char name[VAR_NAME_LEN + 1];
+      char *name;
 
       /* Probably no data exists for this variable, so allocate a
         default width */
       if ( var_spec[i].width == -1 )
        var_spec[i].width = GNUMERIC_DEFAULT_WIDTH;
 
-      if  ( ! dict_make_unique_var_name (r->dict, var_spec[i].name,
-                                        &vstart, name))
-       {
-         msg (ME, _("Cannot create variable name from %s"), var_spec[i].name);
-         goto error;
-       }
-
+      name = dict_make_unique_var_name (r->dict, var_spec[i].name, &vstart);
       dict_create_var (r->dict, name, var_spec[i].width);
+      free (name);
     }
 
   /* Create the first case, and cache it */
diff --git a/src/data/psql-reader.c b/src/data/psql-reader.c
index 76b4674..378a56a 100644
--- a/src/data/psql-reader.c
+++ b/src/data/psql-reader.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
+   Copyright (C) 2008, 2009, 2010, 2011 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 published by
@@ -180,15 +180,12 @@ create_var (struct psql_reader *r, const struct fmt_spec 
*fmt,
 {
   unsigned long int vx = 0;
   struct variable *var;
-  char name[VAR_NAME_LEN + 1];
-
-  if ( ! dict_make_unique_var_name (r->dict, suggested_name, &vx, name))
-    {
-      msg (ME, _("Cannot create variable name from %s"), suggested_name);
-      return NULL;
-    }
+  char *name;
 
+  name = dict_make_unique_var_name (r->dict, suggested_name, &vx);
   var = dict_create_var (r->dict, name, width);
+  free (name);
+
   var_set_both_formats (var, fmt);
 
   if ( col != -1)
diff --git a/src/ui/gui/text-data-import-dialog.c 
b/src/ui/gui/text-data-import-dialog.c
index 8eb4f3c..562f4f2 100644
--- a/src/ui/gui/text-data-import-dialog.c
+++ b/src/ui/gui/text-data-import-dialog.c
@@ -1,5 +1,5 @@
 /* PSPPIRE - a graphical user interface for PSPP.
-   Copyright (C) 2008, 2009, 2010  Free Software Foundation
+   Copyright (C) 2008, 2009, 2010, 2011  Free Software Foundation
 
    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
@@ -1255,15 +1255,13 @@ choose_column_names (struct import_assistant *ia)
   name_row = f->variable_names && f->skip_lines ? f->skip_lines : 0;
   for (col = s->columns; col < &s->columns[s->column_cnt]; col++)
     {
-      char name[VAR_NAME_LEN + 1];
-      char *hint;
+      char *hint, *name;
 
       hint = name_row ? ss_xstrdup (col->contents[name_row - 1]) : NULL;
-      if (!dict_make_unique_var_name (dict, hint, &generated_name_count, name))
-        NOT_REACHED ();
+      name = dict_make_unique_var_name (dict, hint, &generated_name_count);
       free (hint);
 
-      col->name = xstrdup (name);
+      col->name = name;
       dict_create_var_assert (dict, name, 0);
     }
   dict_destroy (dict);
@@ -1601,7 +1599,6 @@ prepare_formats_page (struct import_assistant *ia)
   for (column_idx = 0; column_idx < s->column_cnt; column_idx++)
     {
       struct variable *modified_var;
-      char name[VAR_NAME_LEN + 1];
 
       modified_var = (column_idx < p->modified_var_cnt
                       ? p->modified_vars[column_idx] : NULL);
@@ -1610,11 +1607,11 @@ prepare_formats_page (struct import_assistant *ia)
           struct column *column = &s->columns[column_idx];
           struct variable *var;
           struct fmt_spec format;
+          char *name;
           size_t row;
 
           /* Choose variable name. */
-          if (!dict_make_unique_var_name (dict, column->name, &number, name))
-            NOT_REACHED ();
+          name = dict_make_unique_var_name (dict, column->name, &number);
 
           /* Choose variable format. */
           fmt_guesser_clear (fg);
@@ -1626,13 +1623,17 @@ prepare_formats_page (struct import_assistant *ia)
           /* Create variable. */
           var = dict_create_var_assert (dict, name, fmt_var_width (&format));
           var_set_both_formats (var, &format);
+
+          free (name);
         }
       else
         {
-          if (!dict_make_unique_var_name (dict, var_get_name (modified_var),
-                                          &number, name))
-            NOT_REACHED ();
+          char *name;
+
+          name = dict_make_unique_var_name (dict, var_get_name (modified_var),
+                                            &number);
           dict_clone_var_as_assert (dict, modified_var, name);
+          free (name);
         }
     }
   fmt_guesser_destroy (fg);
-- 
1.7.1