1 files changed, 133 insertions, 0 deletions
diff --git a/libgfortran/runtime/select_inc.c b/libgfortran/runtime/select_inc.c
new file mode 100644
index 000000000..904ad4d86
--- /dev/null
+++ b/libgfortran/runtime/select_inc.c
@@ -0,0 +1,133 @@
+/* Implement the SELECT statement for character variables.
+   Copyright 2008, 2009 Free Software Foundation, Inc.
+
+This file is part of the GNU Fortran runtime library (libgfortran).
+
+Libgfortran 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, or (at your option)
+any later version.
+
+Libgfortran 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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#define select_string SUFFIX(select_string)
+#define select_struct SUFFIX(select_struct)
+#define compare_string SUFFIX(compare_string)
+
+typedef struct
+{
+  CHARTYPE *low;
+  gfc_charlen_type low_len;
+  CHARTYPE *high;
+  gfc_charlen_type high_len;
+  int address;
+}
+select_struct;
+
+extern int select_string (select_struct *table, int table_len,
+			  const CHARTYPE *selector,
+			  gfc_charlen_type selector_len);
+export_proto(select_string);
+
+
+/* select_string()-- Given a selector string and a table of
+ * select_struct structures, return the address to jump to. */
+
+int
+select_string (select_struct *table, int table_len, const CHARTYPE *selector,
+	       gfc_charlen_type selector_len)
+{
+  select_struct *t;
+  int i, low, high, mid;
+  int default_jump = -1;
+
+  if (table_len == 0)
+    return -1;
+
+  /* Record the default address if present */
+
+  if (table->low == NULL && table->high == NULL)
+    {
+      default_jump = table->address;
+
+      table++;
+      table_len--;
+      if (table_len == 0)
+        return default_jump;
+    }
+
+  /* Try the high and low bounds if present. */
+
+  if (table->low == NULL)
+    {
+      if (compare_string (table->high_len, table->high,
+			  selector_len, selector) >= 0)
+        return table->address;
+
+      table++;
+      table_len--;
+      if (table_len == 0)
+        return default_jump;
+    }
+
+  t = table + table_len - 1;
+
+  if (t->high == NULL)
+    {
+      if (compare_string (t->low_len, t->low, selector_len, selector) <= 0)
+        return t->address;
+
+      table_len--;
+      if (table_len == 0)
+        return default_jump;
+    }
+
+  /* At this point, the only table entries are bounded entries.  Find
+     the right entry with a binary chop. */
+
+  low = -1;
+  high = table_len;
+
+  while (low + 1 < high)
+    {
+      mid = (low + high) / 2;
+
+      t = table + mid;
+      i = compare_string (t->low_len, t->low, selector_len, selector);
+
+      if (i == 0)
+        return t->address;
+
+      if (i < 0)
+        low = mid;
+      else
+        high = mid;
+    }
+
+  /* The string now lies between the low indeces of the now-adjacent
+     high and low entries.  Because it is less than the low entry of
+     'high', it can't be that one.  If low is still -1, then no
+     entries match.  Otherwise, we have to check the high entry of
+     'low'. */
+
+  if (low == -1)
+    return default_jump;
+
+  t = table + low;
+  if (compare_string (selector_len, selector, t->high_len, t->high) <= 0)
+    return t->address;
+
+  return default_jump;
+}