LUMIERA.clone/admin/scons/LumieraEnvironment.py

# -*- python -*-
##
## LumieraEnvironment.py  -  custom SCons Environment
##

#  Copyright (C)         Lumiera.org
#    2008,               Hermann Vosseler <Ichthyostega@web.de>
#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License as
#  published by the Free Software Foundation; either version 2 of
#  the License, or (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software
#  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#####################################################################


import os
from os import path

import SCons
import SCons.SConf
from SCons.Environment import Environment

from Buildhelper import *



class LumieraEnvironment(Environment):
    """ Custom SCons build environment for Lumiera
        This allows us to carry structured config data without
        using global vars. Idea inspired by Ardour. 
    """
    def __init__(self, pathConfig, **kw):
        Environment.__init__ (self,**kw)
        self.path = Record (pathConfig)
        self.libInfo = {}
        self.Tool("BuilderGCH")
        self.Tool("BuilderDoxygen")
        self.Tool("ToolDistCC")
        self.Tool("ToolCCache")
        RegisterIcon_Builder(self)
        register_LumieraCustomBuilders(self)
    
    def Configure (self, *args, **kw):
        kw['env'] = self
        return apply(LumieraConfigContext, args, kw)
    
    def mergeConf (self,other):
        """ extract the library/compiler flags from other Environment.
            Optionally accepts a list or just sting(s) representing keys
            in our own libInfo Dictionary
        """
        if isinstance(other, list):
            for elm in other:
                self.mergeConf(elm)
        elif isinstance(other, str):
            if other in self.libInfo:
                self.mergeConf(self.libInfo[other])
        else:
            self.Append (LIBS = other.get ('LIBS',[]))
            self.Append (LIBPATH = other.get ('LIBPATH', []))    
            self.Append (CPPPATH = other.get('CPPPATH', []))
            self.Append (LINKFLAGS = other.get('LINKFLAGS', []))
        
        return self
    
    
    def addLibInfo (self, libID, minVersion=0, alias=None):
        """ use pkg-config to create an Environment describing the lib.
            Don't add this defs to the current Environment, rather store
            them in the libInfo Dictionary. 
        """
        minVersion = str(minVersion)
        if 0 != os.system('pkg-config --print-errors --exists "%s >= %s"' % (libID,minVersion)):
            print "Problems configuring the Library %s (>= %s)" % (libID,minVersion)
            return False
        
        self.libInfo[libID] = libInfo = Environment()
        libInfo["ENV"]["PKG_CONFIG_PATH"] = os.environ.get("PKG_CONFIG_PATH")
        libInfo.ParseConfig ('pkg-config --cflags --libs '+ libID )
        if alias:
            self.libInfo[alias] = libInfo
        return libInfo
    
    
    def SymLink(self, target, source, linktext=None):
        """ use python to create a symlink
        """
        def makeLink(target,source,env):
            if linktext:
                dest = linktext
            else:
                dest = str(source[0])
            link = str(target[0])
            os.symlink(dest, link)
        def reportLink(target,source,env):
            dest = str(source[0])
            link = str(target[0])
            return "Install link %s -> %s" % (link,dest)
        
        action = Action(makeLink,reportLink)
        self.Command (target,source, action)





# extending the 'Configure' functionality of SCons,
# especially for library dependency checking
ConfigBase = SCons.SConf.SConfBase



class LumieraConfigContext(ConfigBase):
    """ Extends the SCons Configure context with some convenience methods
    """
    def __init__(self, *args,**kw):
        ConfigBase.__init__(self,*args,**kw)
    
    def CheckPkgConfig (self, libID, minVersion=0, alias=None):
        print "Checking for library configuration: %s " % libID
        # self.Message(self,"Checking for library configuration: %s " % libID)
        return self.env.addLibInfo (libID, minVersion, alias)



###############################################################################
####### Lumiera custom tools and builders #####################################


def RegisterIcon_Builder(env):
    """ Registers Custom Builders for generating and installing Icons.
        Additionally you need to build the tool (rsvg-convert.c)
        used to generate png from the svg source using librsvg. 
    """
    
    import render_icon as renderer  # load Joel's python script for invoking the rsvg-convert (SVG render)
    renderer.rsvgPath = env.subst("$TARGDIR/rsvg-convert")
    
    def invokeRenderer(target, source, env):
        source = str(source[0])
        targetdir = env.subst("$TARGDIR")
        renderer.main([source,targetdir])
        return 0
        
    def createIconTargets(target,source,env):
        """ parse the SVG to get the target file names """
        source = str(source[0])
        targetdir = os.path.basename(str(target[0]))
        targetfiles = renderer.getTargetNames(source)    # parse SVG
        return (["$TARGDIR/%s" % name for name in targetfiles], source)
    
    def IconCopy(env, source):
         """Copy icon to corresponding icon dir. """
         subdir = getDirname(source)
         return env.Install("$TARGDIR/%s" % subdir, source)
    
    
    buildIcon = env.Builder( action = Action(invokeRenderer, "rendering Icon: $SOURCE --> $TARGETS")
                           , single_source = True
                           , emitter = createIconTargets
                           )
    env.Append(BUILDERS = {'IconRender' : buildIcon})
    env.AddMethod(IconCopy)




class WrappedStandardExeBuilder(SCons.Util.Proxy):
    """ Helper to add customisations and default configurations to SCons standard builders.
        The original builder object is wrapped and most calls are simply forwarded to this
        wrapped object by Python magic. But some calls are intecepted in order to inject
        suitalbe default configuration based on the project setup.
    """
    
    def __init__(self, originalBuilder):
        SCons.Util.Proxy.__init__ (self, originalBuilder)
    
    def __call__(self, env, target=None, source=None, **kw):
        """ when the builder gets invoked from the SConscript...
            create a clone environment for specific configuration
            and then pass on the call to the wrapped original builder
        """
        customisedEnv = self.getCustomEnvironment(env, target=target, **kw)       # defined in subclasses
        buildTarget   = self.buildLocation(customisedEnv, target)
        buildTarget   = self.invokeOriginalBuilder (customisedEnv, buildTarget, source, **kw) 
        return buildTarget + self.installTarget(customisedEnv, buildTarget, **kw)
    
    
    def invokeOriginalBuilder(self, env, target, source, **kw):
        return self.get().__call__ (env, target, source, **kw)
    
    def buildLocation(self, env, target):
        """ prefix project output directory """
        prefix = self.getBuildDestination(env)
        return list(prefix+str(name) for name in target)
    
    def installTarget(self, env, buildTarget, **kw):
        """ create an additional installation target
            for the generated executable artifact
        """
        indeedInstall = lambda p: p and p.get('install')
        
        if indeedInstall(kw):
            return env.Install (dir = self.getInstallDestination(env), source=buildTarget)
        else:
            return []




class LumieraExeBuilder(WrappedStandardExeBuilder):
    
    def getCustomEnvironment(self, lumiEnv, **kw):
        """ augments the built-in Program() builder to add a fixed rpath based on $ORIGIN
            That is: after searching LD_LIBRARY_PATH, but before the standard linker search,
            the directory relative to the position of the executable ($ORIGIN) is searched.
            This search path is active not only for the executable, but for all libraries
            it is linked with.
            @note: enabling the new ELF dynamic tags. This causes a DT_RUNPATH to be set,
                   which results in LD_LIBRARY_PATH being searched *before* the RPATH
        """
        custEnv = lumiEnv.Clone()
        custEnv.Append( LINKFLAGS = "-Wl,-rpath=\\$$ORIGIN/$MODULES,--enable-new-dtags" )
        return custEnv
    
    def getBuildDestination(self, lumiEnv):   return lumiEnv.path.buildExe
    def getInstallDestination(self, lumiEnv): return lumiEnv.path.installExe
        



class LumieraModuleBuilder(WrappedStandardExeBuilder):
    
    def getCustomEnvironment(self, lumiEnv, target, **kw):
        """ augments the built-in SharedLibrary() builder to add  some tweaks missing in SCons 1.0,
            like setting a SONAME proper instead of just passing the relative pathname to the linker
        """
        custEnv = lumiEnv.Clone()
        custEnv.Append(LINKFLAGS = "-Wl,-soname="+self.defineSoname(target,**kw))
        return custEnv
    
    def getBuildDestination(self, lumiEnv):   return lumiEnv.path.buildLib
    def getInstallDestination(self, lumiEnv): return lumiEnv.path.installLib
    
    
    def defineSoname (self, target, **kw):
        """ internal helper to extract or guess
            a suitable library SONAME, either using an
            explicit spec, falling back on the lib filename
        """
        if 'soname' in kw:
            soname = self.subst(kw['soname'])  # explicitely defined by user
        else:                                  # else: use the library filename as DT_SONAME
            if SCons.Util.is_String(target):
                pathname = target.strip()
            elif 1 == len(target):
                pathname = str(target[0]).strip()
            else:
                raise SyntaxError("Lumiera Library builder requires exactly one target spec. Found target="+str(target))
            
            assert pathname
            (dirprefix, libname) = path.split(pathname)
            if not libname:
                raise ValueError("Library name missing. Only got a directory: "+pathname)
            
            soname = "${SHLIBPREFIX}%s$SHLIBSUFFIX" % libname
        
        assert soname
        return soname



class LumieraPluginBuilder(LumieraModuleBuilder):
    
    def getCustomEnvironment(self, lumiEnv, target, **kw):
        """ in addition to the ModuleBuilder, define the Lumiera plugin suffix
        """
        custEnv = LumieraModuleBuilder.getCustomEnvironment(self, lumiEnv, target, **kw)
        custEnv.Append (CPPDEFINES='LUMIERA_PLUGIN')
        custEnv.Replace(SHLIBPREFIX='', SHLIBSUFFIX='.lum')
        return custEnv
    
    def getBuildDestination(self, lumiEnv):   return lumiEnv.path.buildPlug
    def getInstallDestination(self, lumiEnv): return lumiEnv.path.installPlug



def register_LumieraCustomBuilders (lumiEnv):
    """ install the customised builder versions tightly integrated with our buildsystem.
        Especially, these builders automatically add the build and installation locations
        and set the RPATH and SONAME in a way to allow a relocatable Lumiera directory structure
    """
    programBuilder = LumieraExeBuilder    (lumiEnv['BUILDERS']['Program'])
    libraryBuilder = LumieraModuleBuilder (lumiEnv['BUILDERS']['SharedLibrary'])
    smoduleBuilder = LumieraModuleBuilder (lumiEnv['BUILDERS']['LoadableModule'])
    lpluginBuilder = LumieraPluginBuilder (lumiEnv['BUILDERS']['LoadableModule'])
    
    lumiEnv['BUILDERS']['Program']        = programBuilder
    lumiEnv['BUILDERS']['SharedLibrary']  = libraryBuilder
    lumiEnv['BUILDERS']['LoadableModule'] = smoduleBuilder
    lumiEnv['BUILDERS']['LumieraPlugin']  = lpluginBuilder