Add initial support for building on MacOS with homebrew

SConscript

@@ -22,6 +22,9 @@ if platform == 'win32':
     libenv.Append(LIBS = env['UV_LIBS'])
 elif platform == 'posix':
     libenv.Append(CCFLAGS = ['-Wall', '-Wno-format-extra-args'])
+elif platform == 'darwin':
+    libenv.Append(CPPDEFINES = ['__STDC_WANT_LIB_EXT1__=0', 'DARWIN'])
+    libenv.Append(CCFLAGS = ['-Wall', '-Wno-format-extra-args'])
 
 # Include the fuzzing hooks when the sanitizer is enabled
 if platform == 'posix' and env['fsan'] == True:
@@ -106,7 +109,7 @@ if platform == 'posix':
     libenv.Install('#/build/dist/lib', ns3shlib)
 
 swig_docs = []
-if env['python']:
+if env['python'] and platform != 'darwin':
     # Using SWIG to build the python wrapper
     pyenv = libenv.Clone()
     pyenv.VariantDir('swig/py', 'swig')
@@ -162,6 +165,8 @@ if env['nodejs'] and platform == 'posix':
 testenv = env.Clone()
 if testenv['PLATFORM'] == 'win32':
     testenv.Append(CPPDEFINES = ['_CRT_SECURE_NO_WARNINGS', '__STDC_WANT_SECURE_LIB__=0'])
+elif platform == 'darwin':
+    testenv.Append(CPPDEFINES = ['__STDC_WANT_LIB_EXT1__=0', 'DARWIN'])
 testenv.Append(CPPPATH = ['#/ext/safestring/include', 'src'])
 testenv.Append(LIBS = [lib, env['UV_LIBS']])
 
@@ -221,6 +226,8 @@ if platform == 'posix' and env['fsan'] == True:
 exampleenv = env.Clone()
 if exampleenv['PLATFORM'] == 'win32':
     exampleenv.Append(CPPDEFINES = ['_CRT_SECURE_NO_WARNINGS'])
+elif platform == 'darwin':
+    exampleenv.Append(CPPDEFINES = ['__STDC_WANT_LIB_EXT1__=0', 'DARWIN'])
 exampleenv.Append(LIBS = [lib, env['UV_LIBS']])
 
 examplesrcs = ['examples/pub_many.c',

SConstruct

@@ -33,6 +33,11 @@ if platform.system() == 'Linux':
         BoolVariable('fsan', 'Enable fuzzer sanitizer?', False),
         BoolVariable('cov', 'Enable code coverage?', False))
 
+# Darwin-specific command line variables
+if platform.system() == 'Darwin':
+    vars.AddVariables(
+        PathVariable('UV_PATH', 'Path where libuv is installed', '', PathVariable.PathAccept))
+
 tools=['default', 'textfile', DPS]
 # Doxygen is optional
 try:
@@ -213,8 +218,33 @@ elif env['PLATFORM'] == 'posix':
         env.Prepend(LIBPATH = env['UV_PATH'])
         env.Prepend(CPPPATH = env['UV_PATH'] + '/include')
 
+elif env['PLATFORM'] == 'darwin':
+
+    # Treat warnings as errors
+    env.Append(CCFLAGS = ['-Werror'])
+
+    if env['variant'] == 'debug':
+        env.Append(CCFLAGS = ['-O', '-DDPS_DEBUG'])
+    else:
+        env.Append(CCFLAGS = ['-O3', '-DNDEBUG'])
+
+    # Where to find Python.h
+    if env['target'] == 'yocto':
+        env['PY_CPPPATH'] = [os.getenv('SYSROOT') + '/usr/include/python2.7']
+    else:
+        env['PY_CPPPATH'] = ['/usr/include/python2.7']
+    env['PY_LIBPATH'] = []
+
+    # Where to find libuv and the libraries it needs
+    env['UV_LIBS'] = ['uv', 'pthread']
+
+    if env['UV_PATH']:
+        env.Prepend(LIBPATH = env['UV_PATH'])
+        env.Prepend(CPPPATH = env['UV_PATH'] + '/include')
+
 else:
-    print('Unsupported system')
+
+    print('Unsupported system: ' + env['PLATFORM'])
     exit()
 
 env.Append(LIBPATH=['./ext'])

ext/SConscript

@@ -97,6 +97,9 @@ if scEnv['PLATFORM'] == 'win32':
 elif scEnv['PLATFORM'] == 'posix':
     scEnv.Append(CPPDEFINES = ['_ISCO99_SOURCE'])
     scEnv.Append(CFLAGS = ['-Os', '-fPIC', '-std=c99', '-Wall', '-Wextra', '-Wno-unused-parameter', '-Wno-implicit-fallthrough', '-MMD'])
+elif scEnv['PLATFORM'] == 'darwin':
+    scEnv.Append(CPPDEFINES = ['_ISCO99_SOURCE'])
+    scEnv.Append(CFLAGS = ['-Os', '-fPIC', '-std=c99', '-Wall', '-Wextra', '-Wno-unused-parameter', '-Wno-implicit-fallthrough', '-MMD'])
 else:
     print('Unsupported system')
     exit()

src/compat.h

@@ -62,7 +62,9 @@ inline char* strndup(const char* str, size_t maxLen)
 
 #else // posix
 
+#ifndef DARWIN
 #include <endian.h>
+#endif
 
 #define BSWAP_32(n)  __builtin_bswap32(n)
 #define BSWAP_64(n)  __builtin_bswap64(n)