hooks.py

00001 """ Configurable hooks in the build system. Can be used by various platforms
00002 to customize the build process.
00003 """
00004 
00005 ################################################################################
00006 # Hooks for the various parts of the build process
00007 
00008 # Internal mapping of hooks per tool
00009 _HOOKS = {}
00010 
00011 # Internal mapping of running hooks
00012 _RUNNING_HOOKS = {}
00013 
00014 # Available hook types
00015 _HOOK_TYPES = ["binary", "compile", "link", "assemble"]
00016 
00017 # Available hook steps
00018 _HOOK_STEPS = ["pre", "replace", "post"]
00019 
00020 # Hook the given function. Use this function as a decorator
00021 def hook_tool (function):
00022     """Decorate a function as a tool that may be hooked"""
00023     tool = function.__name__
00024     tool_flag = "_" + tool + "_done"
00025     def wrapper(t_self, *args, **kwargs):
00026         """The hooked function itself"""
00027         # if a hook for this tool is already running, it's most likely
00028         # coming from a derived class, so don't hook the super class version
00029         if _RUNNING_HOOKS.get(tool, False):
00030             return function(t_self, *args, **kwargs)
00031         _RUNNING_HOOKS[tool] = True
00032         # If this tool isn't hooked, return original function
00033         if not _HOOKS.has_key(tool):
00034             res = function(t_self, *args, **kwargs)
00035             _RUNNING_HOOKS[tool] = False
00036             return res
00037         tooldesc = _HOOKS[tool]
00038         setattr(t_self, tool_flag, False)
00039         # If there is a replace hook, execute the replacement instead
00040         if tooldesc.has_key("replace"):
00041             res = tooldesc["replace"](t_self, *args, **kwargs)
00042         # If the replacement has set the "done" flag, exit now
00043         # Otherwise continue as usual
00044         if getattr(t_self, tool_flag, False):
00045             _RUNNING_HOOKS[tool] = False
00046             return res
00047         # Execute pre-function before main function if specified
00048         if tooldesc.has_key("pre"):
00049             tooldesc["pre"](t_self, *args, **kwargs)
00050         # Execute the main function now
00051         res = function(t_self, *args, **kwargs)
00052         # Execute post-function after main function if specified
00053         if tooldesc.has_key("post"):
00054             post_res = tooldesc["post"](t_self, *args, **kwargs)
00055             _RUNNING_HOOKS[tool] = False
00056             return post_res or res
00057         else:
00058             _RUNNING_HOOKS[tool] = False
00059             return res
00060     return wrapper
00061 
00062 class Hook (object):
00063     """A compiler class that may be hooked"""
00064     def __init__(self, target, toolchain):
00065         _HOOKS.clear()
00066         self._cmdline_hooks  = {}
00067         self.toolchain  = toolchain
00068         target.init_hooks(self, toolchain)
00069 
00070     # Hook various functions directly
00071     @staticmethod
00072     def _hook_add(hook_type, hook_step, function):
00073         """Add a hook to a compile function
00074 
00075         Positional arguments:
00076         hook_type - one of the _HOOK_TYPES
00077         hook_step - one of the _HOOK_STEPS
00078         function - the function to add to the list of hooks
00079         """
00080         if hook_type not in _HOOK_TYPES or hook_step not in _HOOK_STEPS:
00081             return False
00082         if hook_type not in _HOOKS:
00083             _HOOKS[hook_type] = {}
00084         _HOOKS[hook_type][hook_step] = function
00085         return True
00086 
00087     def hook_add_compiler (self, hook_step, function):
00088         """Add a hook to the compiler
00089 
00090         Positional Arguments:
00091         hook_step - one of the _HOOK_STEPS
00092         function - the function to add to the list of hooks
00093         """
00094         return self._hook_add ("compile", hook_step, function)
00095 
00096     def hook_add_linker (self, hook_step, function):
00097         """Add a hook to the linker
00098 
00099         Positional Arguments:
00100         hook_step - one of the _HOOK_STEPS
00101         function - the function to add to the list of hooks
00102         """
00103         return self._hook_add ("link", hook_step, function)
00104 
00105     def hook_add_assembler (self, hook_step, function):
00106         """Add a hook to the assemble
00107 
00108         Positional Arguments:
00109         hook_step - one of the _HOOK_STEPS
00110         function - the function to add to the list of hooks
00111         """
00112         return self._hook_add ("assemble", hook_step, function)
00113 
00114     def hook_add_binary (self, hook_step, function):
00115         """Add a hook to the elf to binary tool
00116 
00117         Positional Arguments:
00118         hook_step - one of the _HOOK_STEPS
00119         function - the function to add to the list of hooks
00120         """
00121         return self._hook_add ("binary", hook_step, function)
00122 
00123     # Hook command lines
00124     def _hook_cmdline(self, hook_type, function):
00125         """Add a hook to a command line function
00126 
00127         Positional arguments:
00128         hook_type - one of the _HOOK_TYPES
00129         function - the function to add to the list of hooks
00130         """
00131         if hook_type not in _HOOK_TYPES:
00132             return False
00133         self._cmdline_hooks [hook_type] = function
00134         return True
00135 
00136     def hook_cmdline_compiler (self, function):
00137         """Add a hook to the compiler command line
00138 
00139         Positional arguments:
00140         function - the function to call
00141         """
00142         return self._hook_cmdline ("compile", function)
00143 
00144     def hook_cmdline_linker (self, function):
00145         """Add a hook to the linker command line
00146 
00147         Positional arguments:
00148         function - the function to call
00149         """
00150         return self._hook_cmdline ("link", function)
00151 
00152     def hook_cmdline_assembler (self, function):
00153         """Add a hook to the assembler command line
00154 
00155         Positional arguments:
00156         function - the function to call
00157         """
00158         return self._hook_cmdline ("assemble", function)
00159 
00160     def hook_cmdline_binary (self, function):
00161         """Add a hook to the elf to bin tool command line
00162 
00163         Positional arguments:
00164         function - the function to call
00165         """
00166         return self._hook_cmdline ("binary", function)
00167 
00168     # Return the command line after applying the hook
00169     def _get_cmdline(self, hook_type, cmdline):
00170         """Get the command line after running all hooks
00171 
00172         Positional arguments:
00173         hook_type - one of the _HOOK_TYPES
00174         cmdline - the initial command line
00175         """
00176         if self._cmdline_hooks .has_key(hook_type):
00177             cmdline = self._cmdline_hooks [hook_type](
00178                 self.toolchain .__class__.__name__, cmdline)
00179         return cmdline
00180 
00181     def get_cmdline_compiler (self, cmdline):
00182         """Get the compiler command line after running all hooks
00183 
00184         Positional arguments:
00185         cmdline - the initial command line
00186         """
00187         return self._get_cmdline ("compile", cmdline)
00188 
00189     def get_cmdline_linker (self, cmdline):
00190         """Get the linker command line after running all hooks
00191 
00192         Positional arguments:
00193         cmdline - the initial command line
00194         """
00195         return self._get_cmdline ("link", cmdline)
00196 
00197     def get_cmdline_assembler (self, cmdline):
00198         """Get the assmebler command line after running all hooks
00199 
00200         Positional arguments:
00201         cmdline - the initial command line
00202         """
00203         return self._get_cmdline ("assemble", cmdline)
00204 
00205     def get_cmdline_binary (self, cmdline):
00206         """Get the binary command line after running all hooks
00207 
00208         Positional arguments:
00209         cmdline - the initial command line
00210         """
00211         return self._get_cmdline ("binary", cmdline)
00212 
00213 ################################################################################
00214