scons编译protobuffer脚本代码

待我称王封你为后i 2022-08-17 15:26 203阅读 0赞

**scons编译protobuffer脚本代码**

**protoc.py：**

"""
    Google's Protoc builder
    Example, will produce c++ output files in the src directory.
    protoc_cc = env.Protoc(["src/Example.proto"],
        PROTOC_PATH='#src',
        PROTOC_CCOUT='#src',
        )
    """
    
    import os
    import SCons.Util
    from SCons.Script import Builder, Action, Dir, File, Entry
    
    def _detect(env):
        """Try to find the Protoc compiler"""
        try:
            return env['PROTOC']
        except KeyError:
            pass
    
        protoc = env.WhereIs('protoc')
        if protoc:
            return protoc
    
        raise SCons.Errors.StopError(
            "Could not detect protoc Compiler")
    
    def _protoc_emitter(target, source, env):
        """Process target, sources, and flags"""
        
        # always ignore target
        target = []
    
        # suffix
        protoc_suffix = env.subst('$PROTOC_SUFFIX')
        protoc_h_suffix = env.subst('$PROTOC_HSUFFIX')
        protoc_cc_suffix = env.subst('$PROTOC_CCSUFFIX')
        protoc_py_suffix = env.subst('$PROTOC_PYSUFFIX')
        protoc_java_suffix = env.subst('$PROTOC_JAVASUFFIX')
    
        # fetch all protoc flags
        if env['PROTOC_FLAGS']:
            protocflags = env.subst("$PROTOC_FLAGS",
                target=target, source=source)
            flags = SCons.Util.CLVar(protocflags)
        else:
            flags = SCons.Util.CLVar('')
    
        # flag --proto_path, -I
        proto_path = []
        if env['PROTOC_PATH']:
            inc = env['PROTOC_PATH']
            if SCons.Util.is_List(inc):
                for path in inc:
                    path = Dir(path)
                    #print "path:",path
                    proto_path.append(path)
                    flags.append('--proto_path='+str(path.abspath))
            elif SCons.Util.is_Scalar(inc):
                path=Dir(inc)
                #print "path:",path
                proto_path.append(path)
                flags.append('--proto_path='+str(path.abspath))
    
        # flag --cpp_out
        if env['PROTOC_CCOUT']:
            env['PROTOC_CCOUT'] = Dir(env['PROTOC_CCOUT'])
            flags.append('--cpp_out=${PROTOC_CCOUT.abspath}')
        
        # flag --python_out
        if env['PROTOC_PYOUT']:
            env['PROTOC_PYOUT'] = Dir(env['PROTOC_PYOUT'])
            flags.append('--python_out=${PROTOC_PYOUT.abspath}')
    
        # flag --java_out
        if env['PROTOC_JAVAOUT']:
            env['PROTOC_JAVAOUT'] = Dir(env['PROTOC_JAVAOUT'])
            flags.append('--java_out=${PROTOC_JAVAOUT.abspath}')
    
        # updated flags
        env['PROTOC_FLAGS'] = str(flags)
        #print "flags:",flags
    
        # source scons dirs
        src_struct = Dir('#')
        src_script = Dir('.').srcnode()
    
        # produce proper targets
        for src in source:
            src = File(src)
    
            # find proto_path for this source
            longest_common = '/'
            for path in proto_path:
                common = os.path.commonprefix([path.abspath, src.abspath])
                if len(common) > len(longest_common):
                    longest_common = common
            #print "longest_common:",longest_common
    
            src_relpath = os.path.relpath(src.abspath, start=longest_common)
            #print "src_relpath:",src_relpath
    
            # create stem by remove the $PROTOC_SUFFIX or take a guess
            if src_relpath.endswith(protoc_suffix):
                stem = src_relpath[:-len(protoc_suffix)]
            else:
                stem = src_relpath
    
            # C++ output, append
            if env['PROTOC_CCOUT']:
                out = Dir(env['PROTOC_CCOUT'])
                base = os.path.join(out.abspath, stem)
                target.append(File(base+protoc_cc_suffix))
                target.append(File(base+protoc_h_suffix))
    
            # python output, append
            if env['PROTOC_PYOUT']:
                out = Dir(env['PROTOC_PYOUT'])
                base = os.path.join(out.abspath, stem)
                target.append(File(base+protoc_py_suffix))
    
            # java output, append
            if env['PROTOC_JAVAOUT']:
                out = Dir(env['PROTOC_JAVAOUT'])
                base = os.path.join(out.abspath, stem)
                target.append(File(base+protoc_java_suffix))
    
        #print "targets:",env.subst("${TARGETS}", target=target, source=source)
        #print "sources:",env.subst("${SOURCES}", target=target, source=source)
    
        return target, source
    
    
    _protoc_builder = Builder(
            action = Action('$PROTOC_COM', '$PROTOC_COMSTR'),
            suffix = '$PROTOC_CCSUFFIX',
            src_suffix = '$PROTOC_SUFFIX',
            emitter = _protoc_emitter,
            )
    
    def generate(env):
        """Add Builders and construction variables."""
        
        env['PROTOC'] = _detect(env)
        env.SetDefault(
    
            # Additional command-line flags
            PROTOC_FLAGS = SCons.Util.CLVar(''),
    
            # Source path(s)
            PROTOC_PATH = SCons.Util.CLVar(''),
    
            # Output path
            PROTOC_CCOUT = '',
            PROTOC_PYOUT = '',
            PROTOC_JAVAOUT = '',
    
            # Suffixies / prefixes
            PROTOC_SUFFIX = '.proto',
            PROTOC_HSUFFIX = '.pb.h',
            PROTOC_CCSUFFIX = '.pb.cc',
            PROTOC_PYSUFFIX = '_pb2.py',
            PROTOC_JAVASUFFIX = '.java',
    
            # Protoc command
            PROTOC_COM = "$PROTOC $PROTOC_FLAGS $SOURCES.abspath",
            PROTOC_COMSTR = '',
    
            )
    
        env['BUILDERS']['Protoc'] = _protoc_builder
    
    def exists(env):
        return _detect(env)