Makefile: get target platform from compiler

Makefile

@@ -1,4 +1,4 @@
-UNAME := $(shell uname -s)
+SYS := $(shell $(CXX) -dumpmachine)
 SHLIB := libi2pd.so
 ARLIB := libi2pd.a
 SHLIB_CLIENT := libi2pdclient.so
@@ -23,22 +23,24 @@ ifeq ($(WEBSOCKETS),1)
 	NEEDED_CXXFLAGS += -DWITH_EVENTS
 endif
 
-ifeq ($(UNAME),Darwin)
+ifneq (, $(findstring darwin, $(SYS)))
 	DAEMON_SRC += $(DAEMON_SRC_DIR)/UnixDaemon.cpp
 	ifeq ($(HOMEBREW),1)
 		include Makefile.homebrew
 	else
 		include Makefile.osx
 	endif
-else ifeq ($(shell echo $(UNAME) | $(GREP) -Ec '(Free|Open)BSD'),1)
+else ifneq (, $(findstring freebsd, $(SYS))$(findstring openbsd, $(SYS)))
 	DAEMON_SRC += $(DAEMON_SRC_DIR)/UnixDaemon.cpp
 	include Makefile.bsd
-else ifeq ($(UNAME),Linux)
+else ifneq (, $(findstring linux, $(SYS)))
 	DAEMON_SRC += $(DAEMON_SRC_DIR)/UnixDaemon.cpp
 	include Makefile.linux
-else
+else ifneq (, $(findstring mingw, $(SYS))$(findstring cygwin, $(SYS)))
 	DAEMON_SRC += Win32/DaemonWin32.cpp Win32/Win32Service.cpp Win32/Win32App.cpp
 	include Makefile.mingw
+else # not supported
+$(error Not supported platform)
 endif
 
 ifeq ($(USE_MESHNET),yes)

Makefile.bsd

@@ -1,5 +1,5 @@
 CXX = clang++
-CXXFLAGS = -O2
+CXXFLAGS ?= -g -Wall -Wextra -Wno-unused-parameter -pedantic -Wno-misleading-indentation
 ## NOTE: NEEDED_CXXFLAGS is here so that custom CXXFLAGS can be specified at build time
 ## **without** overwriting the CXXFLAGS which we need in order to build.
 ## For example, when adding 'hardening flags' to the build

Makefile.linux

@@ -44,7 +44,7 @@ ifeq ($(USE_STATIC),yes)
 	LDLIBS += -lpthread -static-libstdc++ -static-libgcc -lrt -ldl
 	USE_AESNI := no
 else
-	LDLIBS = -lcrypto -lssl -lz -lboost_system -lboost_date_time -lboost_filesystem -lboost_program_options -lpthread
+	LDLIBS = -lcrypto -lssl -lz -lboost_system -lboost_date_time -lboost_filesystem -lboost_program_options -lpthread -latomic
 endif
 
 # UPNP Support (miniupnpc 1.5 and higher)