From 0982308255dd3fd70e7b93aa88a8f3c5b9c1b845 Mon Sep 17 00:00:00 2001
From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Date: Sun, 30 Aug 2020 21:15:06 +0200
Subject: [PATCH] src/CMakeLists.txt: fix build with mbedtls but without zlib

Building with mbedtls but without zlib will result in the following
build failure:

-- Found MbedTLS: /home/peko/autobuild/instance-0/output-1/per-package/rtty/host/powerpc64-buildroot-linux-gnu/sysroot/usr/lib/libmbedtls.so (found version "2.16.7")
-- Could NOT find ZLIB (missing: ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
-- Select MbedTLS(PolarSSL) as the SSL backend
CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
ZLIB_LIBRARY
    linked by target "rtty" in directory /home/peko/autobuild/instance-0/output-1/build/rtty-7.1.4/src

-- Configuring incomplete, errors occurred!

Fixes:
 - http://autobuild.buildroot.org/results/a0ebffe58bbf14cab74b7d2111d4d88a9c725273

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
[Upstream status: https://github.com/zhaojh329/rtty/pull/77]
---
 src/CMakeLists.txt | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 10f6626..d09e848 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -77,7 +77,11 @@ else()
     elseif(RTTY_USE_MBEDTLS)
         set(SSL_NAME "MbedTLS(PolarSSL)")
         set(SSL_INC ${MBEDTLS_INCLUDE_DIR})
-        set(SSL_LIB ${MBEDTLS_LIBRARIES} ${ZLIB_LIBRARIES})
+        if(ZLIB_FOUND)
+            set(SSL_LIB ${MBEDTLS_LIBRARIES} ${ZLIB_LIBRARIES})
+        else()
+            set(SSL_LIB ${MBEDTLS_LIBRARIES}) 
+        endif()
         set(RTTY_HAVE_MBEDTLS_CONFIG 1)
     endif()
 
-- 
2.28.0