Make socket directory configurable, don't hardcode /tmp/.xrdp

Use XRDP_SOCKET_PATH in file_loc.h

Don't define any non-socket paths in file_loc.h, they should come from
the makefiles.

Define all paths unconditionally, they should not be defined elsewhere.

Pass XRDP_SOCKET_PATH as environment variable to the backends.

xrdpapi/Makefile.am

@@ -3,6 +3,10 @@ EXTRA_DIST = \
   vrplayer.c \
   vrplayer.mk
 
+AM_CPPFLAGS = \
+  -DXRDP_SOCKET_PATH=\"${socketdir}\" \
+  -I$(top_srcdir)/common
+
 module_LTLIBRARIES = \
   libxrdpapi.la
 

xrdpapi/xrdpapi.c

@@ -39,6 +39,7 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 
+#include "file_loc.h"
 #include "xrdpapi.h"
 
 struct wts_obj
@@ -148,7 +149,7 @@ WTSVirtualChannelOpenEx(unsigned int SessionId, const char *pVirtualName,
     memset(&s, 0, sizeof(struct sockaddr_un));
     s.sun_family = AF_UNIX;
     bytes = sizeof(s.sun_path);
-    snprintf(s.sun_path, bytes - 1, "/tmp/.xrdp/xrdpapi_%d", wts->display_num);
+    snprintf(s.sun_path, bytes - 1, CHANSRV_API_STR, wts->display_num);
     s.sun_path[bytes - 1] = 0;
     bytes = sizeof(struct sockaddr_un);