build: add OS= make switch

Overrides the platform detection heuristic. Useful for cross-compiling.

Makefile

@@ -18,21 +18,17 @@
 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 # IN THE SOFTWARE.
 
-uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
-
-ifdef MSVC
-uname_S := MINGW
-endif
+OS ?= $(shell sh -c 'uname -s | tr "[A-Z]" "[a-z]"')
 
 CPPFLAGS += -Iinclude -Iinclude/uv-private
 
-ifeq (Darwin,$(uname_S))
+ifeq (darwin,$(OS))
 SOEXT = dylib
 else
 SOEXT = so
 endif
 
-ifneq (,$(findstring MINGW,$(uname_S)))
+ifneq (,$(findstring mingw,$(OS)))
 include config-mingw.mk
 else
 include config-unix.mk

README.md

@@ -62,7 +62,11 @@ To build via Makefile simply execute:
 
     make
 
-To build with Visual Studio run the vcbuilds.bat file which will
+MinGW users should run this instead:
+
+    make OS=mingw
+
+To build with Visual Studio run the vcbuild.bat file which will
 checkout the GYP code into build/gyp and generate the uv.sln and
 related files.
 

config-unix.mk

@@ -54,21 +54,21 @@ OBJS += src/fs-poll.o
 OBJS += src/uv-common.o
 OBJS += src/inet.o
 
-ifeq (SunOS,$(uname_S))
+ifeq (sunos,$(OS))
 CPPFLAGS += -D__EXTENSIONS__ -D_XOPEN_SOURCE=500
 LDFLAGS+=-lkstat -lnsl -lsendfile -lsocket
 # Library dependencies are not transitive.
 RUNNER_LDFLAGS += $(LDFLAGS)
 OBJS += src/unix/sunos.o
 endif
 
-ifeq (AIX,$(uname_S))
+ifeq (aix,$(OS))
 CPPFLAGS += -Isrc/ares/config_aix -D_ALL_SOURCE -D_XOPEN_SOURCE=500
 LDFLAGS+= -lperfstat
 OBJS += src/unix/aix.o
 endif
 
-ifeq (Darwin,$(uname_S))
+ifeq (darwin,$(OS))
 CPPFLAGS += -D_DARWIN_USE_64_BIT_INODE=1
 LDFLAGS+=-framework CoreServices -dynamiclib -install_name "@rpath/libuv.dylib"
 SOEXT = dylib
@@ -77,7 +77,7 @@ OBJS += src/unix/kqueue.o
 OBJS += src/unix/fsevents.o
 endif
 
-ifeq (Linux,$(uname_S))
+ifeq (linux,$(OS))
 CSTDFLAG += -D_GNU_SOURCE
 LDFLAGS+=-ldl -lrt
 RUNNER_CFLAGS += -D_GNU_SOURCE
@@ -86,38 +86,38 @@ OBJS += src/unix/linux/linux-core.o \
         src/unix/linux/syscalls.o
 endif
 
-ifeq (FreeBSD,$(uname_S))
+ifeq (freebsd,$(OS))
 LDFLAGS+=-lkvm
 OBJS += src/unix/freebsd.o
 OBJS += src/unix/kqueue.o
 endif
 
-ifeq (DragonFly,$(uname_S))
+ifeq (dragonfly,$(OS))
 LDFLAGS+=-lkvm
 OBJS += src/unix/freebsd.o
 OBJS += src/unix/kqueue.o
 endif
 
-ifeq (NetBSD,$(uname_S))
+ifeq (netbsd,$(OS))
 LDFLAGS+=-lkvm
 OBJS += src/unix/netbsd.o
 OBJS += src/unix/kqueue.o
 endif
 
-ifeq (OpenBSD,$(uname_S))
+ifeq (openbsd,$(OS))
 LDFLAGS+=-lkvm
 OBJS += src/unix/openbsd.o
 OBJS += src/unix/kqueue.o
 endif
 
-ifneq (,$(findstring CYGWIN,$(uname_S)))
+ifneq (,$(findstring cygwin,$(OS)))
 # We drop the --std=c89, it hides CLOCK_MONOTONIC on cygwin
 CSTDFLAG = -D_GNU_SOURCE
 LDFLAGS+=
 OBJS += src/unix/cygwin.o
 endif
 
-ifeq (SunOS,$(uname_S))
+ifeq (sunos,$(OS))
 RUNNER_LDFLAGS += -pthreads
 else
 RUNNER_LDFLAGS += -pthread