ssl: Make thread-safety unconditional in rabbitmq-c

Remove the option to disable thread-safety in the parts of rabbitmq-c
that use OpenSSL, making it a requirement for thread-safety to use SSL
with rabbitmq-c.

The existing #ifdef's are a source of additional complexity and the
non-thread-safe version is not well tested.

5 files changed, 26 insertions, 45 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5aea03a..fc07473 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 2.8.12)
 project(rabbitmq-c "C")
 
 # Enable MACOSX_RPATH by default. See: cmake --help-policy CMP0042
@@ -116,6 +116,17 @@ if (CLOCK_GETTIME_NEEDS_LIBRT OR POSIX_SPAWNP_NEEDS_LIBRT)
   set(LIBRT rt)
 endif()
 
+option(ENABLE_SSL_SUPPORT "Enable SSL support" ON)
+
+if (ENABLE_SSL_SUPPORT)
+  find_package(OpenSSL 0.9.8 REQUIRED)
+
+  cmake_push_check_state()
+  set(THREADS_PREFER_PTHREAD_FLAG ON)
+  find_package(Threads REQUIRED)
+  cmake_pop_check_state()
+endif()
+
 if (MSVC)
   set(CMAKE_C_FLAGS "/W4 /nologo ${CMAKE_C_FLAGS}")
 elseif (CMAKE_C_COMPILER_ID MATCHES ".*Clang")
@@ -246,7 +257,6 @@ if (POPT_FOUND AND XmlTo_FOUND)
   set(DO_DOCS ON)
 endif()
 
-find_package(Threads)
 
 option(BUILD_SHARED_LIBS "Build rabbitmq-c as a shared library" ON)
 option(BUILD_STATIC_LIBS "Build rabbitmq-c as a static library" ON)
@@ -256,12 +266,6 @@ option(BUILD_TOOLS "Build Tools (requires POPT Library)" ${POPT_FOUND})
 option(BUILD_TOOLS_DOCS "Build man pages for Tools (requires xmlto)" ${DO_DOCS})
 option(BUILD_TESTS "Build tests (run tests with make test)" ON)
 option(BUILD_API_DOCS "Build Doxygen API docs" ${DOXYGEN_FOUND})
-option(ENABLE_SSL_SUPPORT "Enable SSL support" ON)
-option(ENABLE_THREAD_SAFETY "Enable thread safety when using OpenSSL" ${Threads_FOUND})
-
-if (ENABLE_SSL_SUPPORT)
-  find_package(OpenSSL 0.9.8 REQUIRED)
-endif()
 
 if (NOT BUILD_SHARED_LIBS AND NOT BUILD_STATIC_LIBS)
     message(FATAL_ERROR "One or both of BUILD_SHARED_LIBS or BUILD_STATIC_LIBS must be set to ON to build")
@@ -309,12 +313,8 @@ endif ()
 
 set(libs_private ${SOCKET_LIBRARIES} ${LIBRT})
 if (ENABLE_SSL_SUPPORT)
-  if (SSL_ENGINE STREQUAL "OpenSSL")
-    set(requires_private "openssl")
-  endif()
-  if (ENABLE_THREAD_SAFETY)
-    set(libs_private ${libs_private} ${CMAKE_THREAD_LIBS_INIT})
-  endif()
+  set(requires_private "openssl")
+  set(libs_private ${libs_private} ${CMAKE_THREAD_LIBS_INIT})
 endif()
 
 set(prefix ${CMAKE_INSTALL_PREFIX})
diff --git a/README.md b/README.md
index bfc5c45..5255315 100644
--- a/README.md
+++ b/README.md
@@ -82,8 +82,6 @@ Other interesting flags that can be passed to CMake:
    find the XmlTo utility.
 * `ENABLE_SSL_SUPPORT=ON/OFF` toggles building rabbitmq-c with SSL support. By
    default this is ON if the OpenSSL headers and library can be found.
-* `ENABLE_THREAD_SAFETY=ON/OFF` toggles OpenSSL thread-safety. By default this
-   is ON
 * `BUILD_API_DOCS=ON/OFF` - toggles building the Doxygen API documentation, by
    default this is OFF
 
diff --git a/librabbitmq/CMakeLists.txt b/librabbitmq/CMakeLists.txt
index c5dc663..bd5369a 100644
--- a/librabbitmq/CMakeLists.txt
+++ b/librabbitmq/CMakeLists.txt
@@ -96,13 +96,10 @@ if (ENABLE_SSL_SUPPORT)
       PROPERTIES COMPILE_FLAGS -Wno-deprecated-declarations)
   endif()
 
-  if (ENABLE_THREAD_SAFETY)
-    add_definitions(-DENABLE_THREAD_SAFETY)
-    if (WIN32)
-      set(AMQP_SSL_SRCS ${AMQP_SSL_SRCS} win32/threads.h win32/threads.c)
-    else()
-      set(AMQP_SSL_SRCS ${AMQP_SSL_SRCS} unix/threads.h)
-    endif()
+  if (WIN32)
+    set(AMQP_SSL_SRCS ${AMQP_SSL_SRCS} win32/threads.h win32/threads.c)
+  else()
+    set(AMQP_SSL_SRCS ${AMQP_SSL_SRCS} unix/threads.h)
   endif()
 endif()
 
@@ -122,6 +119,9 @@ set(RMQ_LIBRARIES ${AMQP_SSL_LIBS} ${SOCKET_LIBRARIES} ${LIBRT} ${CMAKE_THREAD_L
 
 if (BUILD_SHARED_LIBS)
     add_library(rabbitmq SHARED ${RABBITMQ_SOURCES})
+    if (THREADS_HAVE_PTHREAD_ARG)
+      target_compile_options(rabbitmq PUBLIC "-pthread")
+    endif()
 
     target_link_libraries(rabbitmq ${RMQ_LIBRARIES})
 
@@ -142,6 +142,9 @@ endif (BUILD_SHARED_LIBS)
 
 if (BUILD_STATIC_LIBS)
     add_library(rabbitmq-static STATIC ${RABBITMQ_SOURCES})
+    if (THREADS_HAVE_PTHREAD_ARG)
+      target_compile_options(rabbitmq-static PUBLIC "-pthread")
+    endif()
 
     target_link_libraries(rabbitmq-static ${RMQ_LIBRARIES})
 
@@ -150,14 +153,14 @@ if (BUILD_STATIC_LIBS)
         set_target_properties(rabbitmq-static PROPERTIES
           VERSION ${RMQ_VERSION}
           OUTPUT_NAME librabbitmq.${RMQ_SOVERSION})
-        
+
         if(MSVC)
             set_target_properties(rabbitmq-static PROPERTIES
             # Embed debugging info in the library itself instead of generating
             # a .pdb file.
             COMPILE_OPTIONS "/Z7")
         endif(MSVC)
-        
+
     else (WIN32)
         set_target_properties(rabbitmq-static PROPERTIES VERSION ${RMQ_VERSION} SOVERSION ${RMQ_SOVERSION} OUTPUT_NAME rabbitmq)
     endif (WIN32)
diff --git a/librabbitmq/amqp_openssl.c b/librabbitmq/amqp_openssl.c
index 417203a..a73cd06 100644
--- a/librabbitmq/amqp_openssl.c
+++ b/librabbitmq/amqp_openssl.c
@@ -54,7 +54,6 @@ static int open_ssl_connections = 0;
 static amqp_boolean_t do_initialize_openssl = 1;
 static amqp_boolean_t openssl_initialized = 0;
 
-#ifdef ENABLE_THREAD_SAFETY
 static unsigned long amqp_ssl_threadid_callback(void);
 static void amqp_ssl_locking_callback(int mode, int n, const char *file,
                                       int line);
@@ -62,7 +61,6 @@ static void amqp_ssl_locking_callback(int mode, int n, const char *file,
 static pthread_mutex_t openssl_init_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 static pthread_mutex_t *amqp_openssl_lockarray = NULL;
-#endif /* ENABLE_THREAD_SAFETY */
 
 struct amqp_ssl_socket_t {
   const struct amqp_socket_class_t *klass;
@@ -532,7 +530,6 @@ void amqp_set_initialize_ssl_library(amqp_boolean_t do_initialize) {
   }
 }
 
-#ifdef ENABLE_THREAD_SAFETY
 unsigned long amqp_ssl_threadid_callback(void) {
   return (unsigned long)pthread_self();
 }
@@ -549,16 +546,12 @@ void amqp_ssl_locking_callback(int mode, int n, AMQP_UNUSED const char *file,
     }
   }
 }
-#endif /* ENABLE_THREAD_SAFETY */
 
 static int initialize_openssl(void) {
-#ifdef ENABLE_THREAD_SAFETY
   if (pthread_mutex_lock(&openssl_init_mutex)) {
     return -1;
   }
-#endif /* ENABLE_THREAD_SAFETY */
   if (do_initialize_openssl) {
-#ifdef ENABLE_THREAD_SAFETY
     if (NULL == amqp_openssl_lockarray) {
       int i = 0;
       amqp_openssl_lockarray =
@@ -581,7 +574,6 @@ static int initialize_openssl(void) {
       CRYPTO_set_id_callback(amqp_ssl_threadid_callback);
       CRYPTO_set_locking_callback(amqp_ssl_locking_callback);
     }
-#endif /* ENABLE_THREAD_SAFETY */
 
     if (!openssl_initialized) {
       OPENSSL_config(NULL);
@@ -595,24 +587,19 @@ static int initialize_openssl(void) {
 
   ++open_ssl_connections;
 
-#ifdef ENABLE_THREAD_SAFETY
   pthread_mutex_unlock(&openssl_init_mutex);
-#endif /* ENABLE_THREAD_SAFETY */
   return 0;
 }
 
 static int destroy_openssl(void) {
-#ifdef ENABLE_THREAD_SAFETY
   if (pthread_mutex_lock(&openssl_init_mutex)) {
     return -1;
   }
-#endif /* ENABLE_THREAD_SAFETY */
 
   if (open_ssl_connections > 0) {
     --open_ssl_connections;
   }
 
-#ifdef ENABLE_THREAD_SAFETY
   if (0 == open_ssl_connections && do_initialize_openssl) {
     /* Unsetting these allows the rabbitmq-c library to be unloaded
      * safely. We do leak the amqp_openssl_lockarray. Which is only
@@ -634,6 +621,5 @@ static int destroy_openssl(void) {
   }
 
   pthread_mutex_unlock(&openssl_init_mutex);
-#endif /* ENABLE_THREAD_SAFETY */
   return 0;
 }
diff --git a/librabbitmq/amqp_openssl_bio.c b/librabbitmq/amqp_openssl_bio.c
index 5279620..df0ce2d 100644
--- a/librabbitmq/amqp_openssl_bio.c
+++ b/librabbitmq/amqp_openssl_bio.c
@@ -42,9 +42,7 @@
 
 #ifdef AMQP_USE_AMQP_BIO
 
-#ifdef ENABLE_THREAD_SAFETY
 static pthread_once_t bio_init_once = PTHREAD_ONCE_INIT;
-#endif
 
 static int bio_initialized = 0;
 static BIO_METHOD amqp_bio_method;
@@ -150,11 +148,7 @@ static void amqp_openssl_bio_init(void) {
 BIO_METHOD *amqp_openssl_bio(void) {
 #ifdef AMQP_USE_AMQP_BIO
   if (!bio_initialized) {
-#ifdef ENABLE_THREAD_SAFETY
     pthread_once(&bio_init_once, amqp_openssl_bio_init);
-#else
-    amqp_openssl_bio_init();
-#endif /* ifndef ENABLE_THREAD_SAFETY */
   }
 
   return &amqp_bio_method;