add support for SO_NOSIGPIPE

The code for creating network sockets previously used `MSG_NOSIGNAL`
unconditionally, which may not exist on non-Linux systems such as
MacOS or some BSD variants. This change adds configuration checks for
`MSG_NOSIGNAL` and it's BSD name, `SO_NOSIGPIPE`, allowing systems with
either socket option to work as intended.

CMakeLists.txt

@@ -294,6 +294,14 @@ endif()
 
 
 # configuration-specific source files
+
+# we don't check for win32 as on win32 socket operations are handled directly through return values
+# Check if SO_NOSIGPIPE exists
+check_symbol_exists(SO_NOSIGPIPE "sys/socket.h" HAVE_SO_NOSIGPIPE)
+
+# Check if MSG_NOSIGNAL exists
+check_symbol_exists(MSG_NOSIGNAL "sys/socket.h" HAVE_MSG_NOSIGNAL)
+
 if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux")
   set(SUPPORT_ABSTRACT_SOCKET_NAMES TRUE)
   list(APPEND STUMPLESS_SOURCES ${PROJECT_SOURCE_DIR}/src/config/abstract_socket_names_supported.c)

include/private/config.h.in

@@ -43,6 +43,9 @@
 #cmakedefine HAVE_VSNPRINTF_S 1
 #cmakedefine HAVE_WCSRTOMBS_S 1
 #cmakedefine HAVE_WCSTOMBS_S 1
+#cmakedefine HAVE_SO_NOSIGPIPE 1
+#cmakedefine HAVE_MSG_NOSIGNAL 1
+
 
 /* function support checks */
 #cmakedefine SUPPORT_ABSTRACT_SOCKET_NAMES 1

include/private/config/have_sys_socket.h

@@ -20,8 +20,15 @@
 #  define __STUMPLESS_PRIVATE_CONFIG_HAVE_SYS_SOCKET_H
 
 #  include <stddef.h>
+#  include <sys/socket.h>
 #  include "private/target/network.h"
 
+#  ifdef HAVE_SO_NOSIGPIPE
+#    define config_disallow_signal_during_sending_flag SO_NOSIGPIPE
+#  elif defined(HAVE_MSG_NOSIGNAL)
+#    define config_disallow_signal_during_sending_flag MSG_NOSIGNAL
+#  endif
+
 void
 sys_socket_close_network_target( const struct network_target *target );
 

src/config/have_sys_socket.c

@@ -204,7 +204,7 @@ sys_socket_sendto_tcp_target( struct network_target *target,
     send_result = send( target->handle,
                         msg,
                         msg_size - sent_bytes,
-                        MSG_NOSIGNAL );
+                        config_disallow_signal_during_sending_flag );
 
     if( unlikely( send_result == -1 ) ){
       raise_socket_send_failure( L10N_SEND_SYS_SOCKET_FAILED_ERROR_MESSAGE,
@@ -231,7 +231,7 @@ sys_socket_sendto_udp_target( const struct network_target *target,
   send_result = send( target->handle,
                       msg,
                       msg_size,
-                      MSG_NOSIGNAL );
+                      config_disallow_signal_during_sending_flag );
 
   if( unlikely( send_result == -1 ) ){
     unlock_network_target( target );