taler-android

Android apps for GNU Taler (wallet, PoS, cashier)
Log | Files | Refs | README | LICENSE

Version.kt (2371B)

      1 /*
      2  * This file is part of GNU Taler
      3  * (C) 2020 Taler Systems S.A.
      4  *
      5  * GNU Taler is free software; you can redistribute it and/or modify it under the
      6  * terms of the GNU General Public License as published by the Free Software
      7  * Foundation; either version 3, or (at your option) any later version.
      8  *
      9  * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
     10  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
     11  * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
     12  *
     13  * You should have received a copy of the GNU General Public License along with
     14  * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
     15  */
     16 
     17 package net.taler.common
     18 
     19 import kotlin.math.sign
     20 
     21 /**
     22  * Semantic versioning, but libtool-style.
     23  * See https://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html
     24  */
     25 public data class Version(
     26     val current: Int,
     27     val revision: Int,
     28     val age: Int
     29 ) {
     30     public companion object {
     31         public fun parse(v: String): Version? {
     32             val elements = v.split(":")
     33             if (elements.size != 3) return null
     34             val (currentStr, revisionStr, ageStr) = elements
     35             val current = currentStr.toIntOrNull()
     36             val revision = revisionStr.toIntOrNull()
     37             val age = ageStr.toIntOrNull()
     38             if (current == null || revision == null || age == null) return null
     39             return Version(current, revision, age)
     40         }
     41     }
     42 
     43     /**
     44      * Compare two libtool-style versions.
     45      *
     46      * Returns a [VersionMatchResult] or null if the given version was null.
     47      */
     48     public fun compare(other: Version?): VersionMatchResult? {
     49         if (other == null) return null
     50         val compatible = current - age <= other.current &&
     51                 current >= other.current - other.age
     52         val currentCmp = sign((current - other.current).toDouble()).toInt()
     53         return VersionMatchResult(compatible, currentCmp)
     54     }
     55 
     56     /**
     57      * Result of comparing two libtool versions.
     58      */
     59     public data class VersionMatchResult(
     60         /**
     61          * Is the first version compatible with the second?
     62          */
     63         val compatible: Boolean,
     64         /**
     65          * Is the first version older (-1), newer (+1) or identical (0)?
     66          */
     67         val currentCmp: Int
     68     )
     69 
     70 }