1 files changed, 90 insertions, 0 deletions
diff --git a/ext/bcmath/libbcmath/src/sub.c b/ext/bcmath/libbcmath/src/sub.c
new file mode 100644
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+++ b/ext/bcmath/libbcmath/src/sub.c
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+/* sub.c: bcmath library file. */
+/*
+    Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
+    Copyright (C) 2000 Philip A. Nelson
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library 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
+    Lesser General Public License for more details.  (COPYING.LIB)
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to:
+
+      The Free Software Foundation, Inc.
+      59 Temple Place, Suite 330
+      Boston, MA 02111-1307 USA.
+
+    You may contact the author by:
+       e-mail:  philnelson@acm.org
+      us-mail:  Philip A. Nelson
+                Computer Science Department, 9062
+                Western Washington University
+                Bellingham, WA 98226-9062
+       
+*************************************************************************/
+
+#include <config.h>
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <stdarg.h>
+#include "bcmath.h"
+#include "private.h"
+
+
+/* Here is the full subtract routine that takes care of negative numbers.
+   N2 is subtracted from N1 and the result placed in RESULT.  SCALE_MIN
+   is the minimum scale for the result. */
+
+void
+bc_sub (n1, n2, result, scale_min)
+     bc_num n1, n2, *result;
+     int scale_min;
+{
+  bc_num diff = NULL;
+  int cmp_res;
+  int res_scale;
+
+  if (n1->n_sign != n2->n_sign)
+    {
+      diff = _bc_do_add (n1, n2, scale_min);
+      diff->n_sign = n1->n_sign;
+    }
+  else
+    {
+      /* subtraction must be done. */
+      /* Compare magnitudes. */
+      cmp_res = _bc_do_compare (n1, n2, FALSE, FALSE);
+      switch (cmp_res)
+	{
+	case -1:
+	  /* n1 is less than n2, subtract n1 from n2. */
+	  diff = _bc_do_sub (n2, n1, scale_min);
+	  diff->n_sign = (n2->n_sign == PLUS ? MINUS : PLUS);
+	  break;
+	case  0:
+	  /* They are equal! return zero! */
+	  res_scale = MAX (scale_min, MAX(n1->n_scale, n2->n_scale));
+	  diff = bc_new_num (1, res_scale);
+	  memset (diff->n_value, 0, res_scale+1);
+	  break;
+	case  1:
+	  /* n2 is less than n1, subtract n2 from n1. */
+	  diff = _bc_do_sub (n1, n2, scale_min);
+	  diff->n_sign = n1->n_sign;
+	  break;
+	}
+    }
+
+  /* Clean up and return. */
+  bc_free_num (result);
+  *result = diff;
+}
+