From afb2a1587a828bf7cd7ddd87b2e2609a9bb7fab0 Mon Sep 17 00:00:00 2001
From: Eneas U de Queiroz <cotequeiroz@gmail.com>
Date: Wed, 6 May 2020 08:59:54 -0300
Subject: [PATCH] Add SOVERSION info to library when using cmake

Currently the SOVERSION is different when building with cmake than the
value used by autotools.
This adds the version information from autotools to cmake.

Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 29a1417..1c8a090 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -67,6 +67,19 @@ target_include_directories(onig PUBLIC
 target_compile_definitions(onig PUBLIC
   $<$<NOT:$<BOOL:${BUILD_SHARED_LIBS}>>:ONIG_STATIC>)
 
+if(BUILD_SHARED_LIBS)
+  # Parse SOVERSION information from LTVERSION in configure.ac
+  file(STRINGS "${CMAKE_CURRENT_SOURCE_DIR}/configure.ac" LTVERSION REGEX "^LTVERSION *= *\"?[0-9]+:[0-9]+:[0-9]+\"?")
+  string(REGEX REPLACE "^LTVERSION *= *\"?([0-9]+:[0-9]+:[0-9]+)\"?.*$" "\\1" LTVERSION "${LTVERSION}")
+  string(REGEX REPLACE "^([0-9]+):([0-9]+):([0-9]+)" "\\1" LTCURRENT ${LTVERSION})
+  string(REGEX REPLACE "^([0-9]+):([0-9]+):([0-9]+)" "\\2" LTREVISION ${LTVERSION})
+  string(REGEX REPLACE "^([0-9]+):([0-9]+):([0-9]+)" "\\3" LTAGE ${LTVERSION})
+  math(EXPR ONIG_SOVERSION "${LTCURRENT} - ${LTAGE}")
+  set_target_properties(onig PROPERTIES
+      SOVERSION "${ONIG_SOVERSION}"
+      VERSION "${ONIG_SOVERSION}.${LTAGE}.${LTREVISION}")
+endif()
+
 if(MSVC)
   target_compile_options(onig PRIVATE
 	#/W4