| """Routine to "compile" a .py file to a .pyc (or .pyo) file. | 
 |  | 
 | This module has intimate knowledge of the format of .pyc files. | 
 | """ | 
 |  | 
 | import builtins | 
 | import errno | 
 | import imp | 
 | import marshal | 
 | import os | 
 | import sys | 
 | import tokenize | 
 | import traceback | 
 |  | 
 | MAGIC = imp.get_magic() | 
 |  | 
 | __all__ = ["compile", "main", "PyCompileError"] | 
 |  | 
 |  | 
 | class PyCompileError(Exception): | 
 |     """Exception raised when an error occurs while attempting to | 
 |     compile the file. | 
 |  | 
 |     To raise this exception, use | 
 |  | 
 |         raise PyCompileError(exc_type,exc_value,file[,msg]) | 
 |  | 
 |     where | 
 |  | 
 |         exc_type:   exception type to be used in error message | 
 |                     type name can be accesses as class variable | 
 |                     'exc_type_name' | 
 |  | 
 |         exc_value:  exception value to be used in error message | 
 |                     can be accesses as class variable 'exc_value' | 
 |  | 
 |         file:       name of file being compiled to be used in error message | 
 |                     can be accesses as class variable 'file' | 
 |  | 
 |         msg:        string message to be written as error message | 
 |                     If no value is given, a default exception message will be | 
 |                     given, consistent with 'standard' py_compile output. | 
 |                     message (or default) can be accesses as class variable | 
 |                     'msg' | 
 |  | 
 |     """ | 
 |  | 
 |     def __init__(self, exc_type, exc_value, file, msg=''): | 
 |         exc_type_name = exc_type.__name__ | 
 |         if exc_type is SyntaxError: | 
 |             tbtext = ''.join(traceback.format_exception_only( | 
 |                 exc_type, exc_value)) | 
 |             errmsg = tbtext.replace('File "<string>"', 'File "%s"' % file) | 
 |         else: | 
 |             errmsg = "Sorry: %s: %s" % (exc_type_name,exc_value) | 
 |  | 
 |         Exception.__init__(self,msg or errmsg,exc_type_name,exc_value,file) | 
 |  | 
 |         self.exc_type_name = exc_type_name | 
 |         self.exc_value = exc_value | 
 |         self.file = file | 
 |         self.msg = msg or errmsg | 
 |  | 
 |     def __str__(self): | 
 |         return self.msg | 
 |  | 
 |  | 
 | def wr_long(f, x): | 
 |     """Internal; write a 32-bit int to a file in little-endian order.""" | 
 |     f.write(bytes([x         & 0xff, | 
 |                    (x >> 8)  & 0xff, | 
 |                    (x >> 16) & 0xff, | 
 |                    (x >> 24) & 0xff])) | 
 |  | 
 | def compile(file, cfile=None, dfile=None, doraise=False, optimize=-1): | 
 |     """Byte-compile one Python source file to Python bytecode. | 
 |  | 
 |     :param file: The source file name. | 
 |     :param cfile: The target byte compiled file name.  When not given, this | 
 |         defaults to the PEP 3147 location. | 
 |     :param dfile: Purported file name, i.e. the file name that shows up in | 
 |         error messages.  Defaults to the source file name. | 
 |     :param doraise: Flag indicating whether or not an exception should be | 
 |         raised when a compile error is found.  If an exception occurs and this | 
 |         flag is set to False, a string indicating the nature of the exception | 
 |         will be printed, and the function will return to the caller. If an | 
 |         exception occurs and this flag is set to True, a PyCompileError | 
 |         exception will be raised. | 
 |     :param optimize: The optimization level for the compiler.  Valid values | 
 |         are -1, 0, 1 and 2.  A value of -1 means to use the optimization | 
 |         level of the current interpreter, as given by -O command line options. | 
 |  | 
 |     :return: Path to the resulting byte compiled file. | 
 |  | 
 |     Note that it isn't necessary to byte-compile Python modules for | 
 |     execution efficiency -- Python itself byte-compiles a module when | 
 |     it is loaded, and if it can, writes out the bytecode to the | 
 |     corresponding .pyc (or .pyo) file. | 
 |  | 
 |     However, if a Python installation is shared between users, it is a | 
 |     good idea to byte-compile all modules upon installation, since | 
 |     other users may not be able to write in the source directories, | 
 |     and thus they won't be able to write the .pyc/.pyo file, and then | 
 |     they would be byte-compiling every module each time it is loaded. | 
 |     This can slow down program start-up considerably. | 
 |  | 
 |     See compileall.py for a script/module that uses this module to | 
 |     byte-compile all installed files (or all files in selected | 
 |     directories). | 
 |     """ | 
 |     with tokenize.open(file) as f: | 
 |         try: | 
 |             st = os.fstat(f.fileno()) | 
 |         except AttributeError: | 
 |             st = os.stat(file) | 
 |         timestamp = int(st.st_mtime) | 
 |         size = st.st_size & 0xFFFFFFFF | 
 |         codestring = f.read() | 
 |     try: | 
 |         codeobject = builtins.compile(codestring, dfile or file, 'exec', | 
 |                                       optimize=optimize) | 
 |     except Exception as err: | 
 |         py_exc = PyCompileError(err.__class__, err, dfile or file) | 
 |         if doraise: | 
 |             raise py_exc | 
 |         else: | 
 |             sys.stderr.write(py_exc.msg + '\n') | 
 |             return | 
 |     if cfile is None: | 
 |         if optimize >= 0: | 
 |             cfile = imp.cache_from_source(file, debug_override=not optimize) | 
 |         else: | 
 |             cfile = imp.cache_from_source(file) | 
 |     try: | 
 |         dirname = os.path.dirname(cfile) | 
 |         if dirname: | 
 |             os.makedirs(dirname) | 
 |     except OSError as error: | 
 |         if error.errno != errno.EEXIST: | 
 |             raise | 
 |     with open(cfile, 'wb') as fc: | 
 |         fc.write(b'\0\0\0\0') | 
 |         wr_long(fc, timestamp) | 
 |         wr_long(fc, size) | 
 |         marshal.dump(codeobject, fc) | 
 |         fc.flush() | 
 |         fc.seek(0, 0) | 
 |         fc.write(MAGIC) | 
 |     return cfile | 
 |  | 
 | def main(args=None): | 
 |     """Compile several source files. | 
 |  | 
 |     The files named in 'args' (or on the command line, if 'args' is | 
 |     not specified) are compiled and the resulting bytecode is cached | 
 |     in the normal manner.  This function does not search a directory | 
 |     structure to locate source files; it only compiles files named | 
 |     explicitly.  If '-' is the only parameter in args, the list of | 
 |     files is taken from standard input. | 
 |  | 
 |     """ | 
 |     if args is None: | 
 |         args = sys.argv[1:] | 
 |     rv = 0 | 
 |     if args == ['-']: | 
 |         while True: | 
 |             filename = sys.stdin.readline() | 
 |             if not filename: | 
 |                 break | 
 |             filename = filename.rstrip('\n') | 
 |             try: | 
 |                 compile(filename, doraise=True) | 
 |             except PyCompileError as error: | 
 |                 rv = 1 | 
 |                 sys.stderr.write("%s\n" % error.msg) | 
 |             except IOError as error: | 
 |                 rv = 1 | 
 |                 sys.stderr.write("%s\n" % error) | 
 |     else: | 
 |         for filename in args: | 
 |             try: | 
 |                 compile(filename, doraise=True) | 
 |             except PyCompileError as error: | 
 |                 # return value to indicate at least one failure | 
 |                 rv = 1 | 
 |                 sys.stderr.write(error.msg) | 
 |     return rv | 
 |  | 
 | if __name__ == "__main__": | 
 |     sys.exit(main()) |