1 files changed, 57 insertions, 0 deletions
diff --git a/src/libs/libgroff/ptable.cpp b/src/libs/libgroff/ptable.cpp
new file mode 100644
index 0000000..52d09f8
--- /dev/null
+++ b/src/libs/libgroff/ptable.cpp
@@ -0,0 +1,57 @@
+/* Copyright (C) 1989-2020 Free Software Foundation, Inc.
+     Written by James Clark (jjc@jclark.com)
+
+This file is part of groff.
+
+groff 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.
+
+groff 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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include "ptable.h"
+#include "errarg.h"
+#include "error.h"
+
+unsigned long hash_string(const char *s)
+{
+  // This is the mythical Aho-Hopcroft-Ullman hash function.
+  // TODO: Improve.  See http://www.haible.de/bruno/hashfunc.html
+  assert(s != 0);
+  unsigned long h = 0, g;
+  while (*s != 0) {
+    h <<= 4;
+    h += *s++;
+    if ((g = h & 0xf0000000) != 0) {
+      h ^= g >> 24;
+      h ^= g;
+    }
+  }
+  return h;
+}
+
+static const unsigned table_sizes[] = { 
+  101, 503, 1009, 2003, 3001, 4001, 5003, 10007, 20011, 40009,
+  80021, 160001, 500009, 1000003, 2000003, 4000037, 8000009,
+  16000057, 32000011, 64000031, 128000003, 0 
+};
+
+unsigned next_ptable_size(unsigned n)
+{
+  const unsigned *p;  
+  for (p = table_sizes; *p <= n; p++)
+    if (*p == 0)
+      fatal("cannot expand table");
+  return *p;
+}
+
+// end of ptable.cpp