added checkTag

checkTag verifies that provided tag and library version match.
It's started automatically in circleCI when a new tag is created.

.travis.yml

@@ -145,7 +145,15 @@ matrix:
             - gcc-multilib
             - gcc-4.4
 
+    # tag-specific test
+    - if: tag =~ ^v[0-9]\.[0-9]
+      os: linux
+      sudo: false
+      env: Cmd="make -C tests checkTag && tests/checkTag $TRAVIS_BRANCH " COMPILER=cc
+
+
 script:
+  - uname -a
   - echo Cmd=$Cmd
   - $COMPILER -v
   - sh -c "$Cmd"

tests/.gitignore

@@ -8,6 +8,7 @@ fullbench32
 fuzzer
 fuzzer32
 fasttest
+checkTag
 
 # test artefacts
 tmp*

tests/Makefile

@@ -111,7 +111,7 @@ clean:
         fullbench$(EXT) fullbench32$(EXT) \
         fuzzer$(EXT) fuzzer32$(EXT) \
         frametest$(EXT) frametest32$(EXT) \
-        fasttest$(EXT) datagen$(EXT)
+        fasttest$(EXT) datagen$(EXT) checkTag$(EXT)
 	@rm -fR $(TESTDIR)
 	@echo Cleaning completed
 
@@ -119,6 +119,9 @@ clean:
 versionsTest:
 	$(PYTHON) test-lz4-versions.py
 
+checkTag: checkTag.c $(LZ4DIR)/lz4.h
+	$(CC) $(FLAGS) $< -o $@$(EXT)
+
 
 #-----------------------------------------------------------------------------
 # validated only for Linux, OSX, BSD, Hurd and Solaris targets

tests/checkTag.c

@@ -0,0 +1,79 @@
+/*
+    checkTag.c - Version validation tool for LZ4
+    Copyright (C) Yann Collet 2018 - present
+
+    GPL v2 License
+
+    This program 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 2 of the License, or
+    (at your option) any later version.
+
+    This program 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, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+    You can contact the author at :
+    - LZ4 homepage : http://www.lz4.org
+    - LZ4 source repo : https://github.com/lz4/lz4
+*/
+
+/* checkTag command :
+ * $ ./checkTag tag
+ * checkTag validates tags of following format : v[0-9].[0-9].[0-9]{any}
+ * The tag is then compared to LZ4 version number.
+ * They are compatible if first 3 digits are identical.
+ * Anything beyond that is free, and doesn't impact validation.
+ * Example : tag v1.8.1.2 is compatible with version 1.8.1
+ * When tag and version are not compatible, program exits with error code 1.
+ * When they are compatible, it exists with a code 0.
+ * checkTag is intended to be used in automated testing environment.
+ */
+
+#include <stdio.h>   /* printf */
+#include <string.h>  /* strlen, strncmp */
+#include "lz4.h"     /* LZ4_VERSION_STRING */
+
+
+/*  validate() :
+ * @return 1 if tag is compatible, 0 if not.
+ */
+static int validate(const char* const tag)
+{
+    size_t const tagLength = strlen(tag);
+    size_t const verLength = strlen(LZ4_VERSION_STRING);
+
+    if (tagLength < 2) return 0;
+    if (tag[0] != 'v') return 0;
+    if (tagLength <= verLength) return 0;
+
+    if (strncmp(LZ4_VERSION_STRING, tag+1, verLength)) return 0;
+
+    return 1;
+}
+
+int main(int argc, const char** argv)
+{
+    const char* const exeName = argv[0];
+    const char* const tag = argv[1];
+    if (argc!=2) {
+        printf("incorrect usage : %s tag \n", exeName);
+        return 2;
+    }
+
+    printf("Version : %s \n", LZ4_VERSION_STRING);
+    printf("Tag     : %s \n", tag);
+
+    if (validate(tag)) {
+        printf("OK : tag is compatible with lz4 version \n");
+        return 0;
+    }
+
+    printf("!! error : tag and versions are not compatible !! \n");
+    return 1;
+}