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"""Routine to "compile" a .py file to a .pyc (or .pyo) file.
This module has intimate knowledge of the format of .pyc files.
"""
import imp
MAGIC = imp.get_magic()
__all__ = ["compile"]
def wr_long(f, x):
"""Internal; write a 32-bit int to a file in little-endian order."""
f.write(chr( x & 0xff))
f.write(chr((x >> 8) & 0xff))
f.write(chr((x >> 16) & 0xff))
f.write(chr((x >> 24) & 0xff))
def compile(file, cfile=None, dfile=None):
"""Byte-compile one Python source file to Python bytecode.
Arguments:
file: source filename
cfile: target filename; defaults to source with 'c' or 'o' appended
('c' normally, 'o' in optimizing mode, giving .pyc or .pyo)
dfile: purported filename; defaults to source (this is the filename
that will show up in error messages)
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).
"""
import os, marshal, __builtin__
f = open(file)
try:
timestamp = long(os.fstat(f.fileno())[8])
except AttributeError:
timestamp = long(os.stat(file)[8])
codestring = f.read()
# If parsing from a string, line breaks are \n (see parsetok.c:tok_nextc)
# Replace will return original string if pattern is not found, so
# we don't need to check whether it is found first.
codestring = codestring.replace("\r\n","\n")
codestring = codestring.replace("\r","\n")
f.close()
if codestring and codestring[-1] != '\n':
codestring = codestring + '\n'
try:
codeobject = __builtin__.compile(codestring, dfile or file, 'exec')
except SyntaxError, detail:
import traceback, sys
lines = traceback.format_exception_only(SyntaxError, detail)
for line in lines:
sys.stderr.write(line.replace('File "<string>"',
'File "%s"' % (dfile or file)))
return
if not cfile:
cfile = file + (__debug__ and 'c' or 'o')
fc = open(cfile, 'wb')
fc.write('\0\0\0\0')
wr_long(fc, timestamp)
marshal.dump(codeobject, fc)
fc.flush()
fc.seek(0, 0)
fc.write(MAGIC)
fc.close()
if os.name == 'mac':
import macfs
macfs.FSSpec(cfile).SetCreatorType('Pyth', 'PYC ')
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