Lib/ctypes/util.py

   1 import sys, os
   2 import ctypes
   3
   4 # find_library(name) returns the pathname of a library, or None.
   5 if os.name == "nt":
   6     def find_library(name):
   7         # See MSDN for the REAL search order.
   8         for directory in os.environ['PATH'].split(os.pathsep):
   9             fname = os.path.join(directory, name)
  10             if os.path.exists(fname):
  11                 return fname
  12             if fname.lower().endswith(".dll"):
  13                 continue
  14             fname = fname + ".dll"
  15             if os.path.exists(fname):
  16                 return fname
  17         return None
  18
  19 if os.name == "ce":
  20     # search path according to MSDN:
  21     # - absolute path specified by filename
  22     # - The .exe launch directory
  23     # - the Windows directory
  24     # - ROM dll files (where are they?)
  25     # - OEM specified search path: HKLM\Loader\SystemPath
  26     def find_library(name):
  27         return name
  28
  29 if os.name == "posix" and sys.platform == "darwin":
  30     from ctypes.macholib.dyld import dyld_find as _dyld_find
  31     def find_library(name):
  32         possible = ['lib%s.dylib' % name,
  33                     '%s.dylib' % name,
  34                     '%s.framework/%s' % (name, name)]
  35         for name in possible:
  36             try:
  37                 return _dyld_find(name)
  38             except ValueError:
  39                 continue
  40         return None
  41
  42 elif os.name == "posix":
  43     # Andreas Degert's find functions, using gcc, /sbin/ldconfig, objdump
  44     import re, tempfile
  45
  46     def _findLib_gcc(name):
  47         expr = '[^\(\)\s]*lib%s\.[^\(\)\s]*' % name
  48         cmd = 'if type gcc &>/dev/null; then CC=gcc; else CC=cc; fi;' \
  49               '$CC -Wl,-t -o /dev/null 2>&1 -l' + name
  50         try:
  51             fdout, outfile =  tempfile.mkstemp()
  52             fd = os.popen(cmd)
  53             trace = fd.read()
  54             err = fd.close()
  55         finally:
  56             try:
  57                 os.unlink(outfile)
  58             except OSError, e:
  59                 if e.errno != errno.ENOENT:
  60                     raise
  61         res = re.search(expr, trace)
  62         if not res:
  63             return None
  64         return res.group(0)
  65
  66     def _findLib_ld(name):
  67         expr = '/[^\(\)\s]*lib%s\.[^\(\)\s]*' % name
  68         res = re.search(expr, os.popen('/sbin/ldconfig -p 2>/dev/null').read())
  69         if not res:
  70             # Hm, this works only for libs needed by the python executable.
  71             cmd = 'ldd %s 2>/dev/null' % sys.executable
  72             res = re.search(expr, os.popen(cmd).read())
  73             if not res:
  74                 return None
  75         return res.group(0)
  76
  77     def _get_soname(f):
  78         cmd = "objdump -p -j .dynamic 2>/dev/null " + f
  79         res = re.search(r'\sSONAME\s+([^\s]+)', os.popen(cmd).read())
  80         if not res:
  81             return None
  82         return res.group(1)
  83
  84     def find_library(name):
  85         lib = _findLib_ld(name) or _findLib_gcc(name)
  86         if not lib:
  87             return None
  88         return _get_soname(lib)
  89
  90 ################################################################
  91 # test code
  92
  93 def test():
  94     from ctypes import cdll
  95     if os.name == "nt":
  96         print cdll.msvcrt
  97         print cdll.load("msvcrt")
  98         print find_library("msvcrt")
  99
 100     if os.name == "posix":
 101         # find and load_version
 102         print find_library("m")
 103         print find_library("c")
 104         print find_library("bz2")
 105
 106         # getattr
 107 ##        print cdll.m
 108 ##        print cdll.bz2
 109
 110         # load
 111         if sys.platform == "darwin":
 112             print cdll.LoadLibrary("libm.dylib")
 113             print cdll.LoadLibrary("libcrypto.dylib")
 114             print cdll.LoadLibrary("libSystem.dylib")
 115             print cdll.LoadLibrary("System.framework/System")
 116         else:
 117             print cdll.LoadLibrary("libm.so")
 118             print cdll.LoadLibrary("libcrypt.so")
 119             print find_library("crypt")
 120
 121 if __name__ == "__main__":
 122     test()