Infrastructure: Split the files into subdirectories.

[mLib] / utils / versioncmp.h

diff --git a/utils/versioncmp.h b/utils/versioncmp.h
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+/* -*-c-*-
+ *
+ * Compare version numbers using the Debian algorithm
+ *
+ * (c) 2007 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the mLib utilities library.
+ *
+ * mLib is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * mLib 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 Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with mLib; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#ifndef MLIB_VERSIONCMP_H
+#define MLIB_VERSIONCMP_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+/*----- Functions provided ------------------------------------------------*/
+
+/* --- @versioncmp@ --- *
+ *
+ * Arguments:  @const char *va, *vb@ = two version strings
+ *
+ * Returns:    Less than, equal to, or greater than zero, according to
+ *             whether @va@ is less than, equal to, or greater than @vb@.
+ *
+ * Use:                Compares version number strings.
+ *
+ *             The algorithm is an extension of the Debian version
+ *             comparison algorithm.  A version number consists of three
+ *             components:
+ *
+ *               [EPOCH :] MAIN [- SUB]
+ *
+ *             The MAIN part may contain colons or hyphens if there is an
+ *             EPOCH or SUB, respectively.  Version strings are compared
+ *             componentwise: first epochs, then main parts, and finally
+ *             subparts.
+ *
+ *             The component comparison is done as follows.  First, the
+ *             initial subsequence of nondigit characters is extracted from
+ *             each string, and these are compared lexicographically, using
+ *             ASCII ordering, except that letters precede non-letters.  If
+ *             both are the same, an initial sequence of digits is extracted
+ *             from the remaining parts of the version strings, and these
+ *             are compared numerically (an empty sequence being considered
+ *             to have the value zero).  This process is repeated until we
+ *             have a winner or until both strings are exhausted.
+ */
+
+extern int versioncmp(const char */*va*/, const char */*vb*/);
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif