Lendo o destino de um arquivo .lnk em Python?

Question

Eu estou tentando ler o alvo arquivo / diretório de um arquivo de atalho (.lnk) do Python. Existe uma maneira livre de dor de cabeça para fazê-lo? A .lnk especificação [PDF] é maneira sobre a minha cabeça. Eu não me importo com o Windows somente APIs.

Meu objetivo final é encontrar a pasta "(My) Videos" no Windows XP e Vista. No XP, por padrão, é no %HOMEPATH%\My Documents\My Videos, e no Vista é %HOMEPATH%\Videos. No entanto, o usuário pode mudar esta pasta. No caso, a pasta %HOMEPATH%\Videos deixa de existe e é substituído por %HOMEPATH%\Videos.lnk que aponta para a nova pasta "My Videos". E eu quero a sua localização absoluta.

Answer 1

Criar um atalho usando Python (via WSH)

import sys
import win32com.client 

shell = win32com.client.Dispatch("WScript.Shell")
shortcut = shell.CreateShortCut("t:\\test.lnk")
shortcut.Targetpath = "t:\\ftemp"
shortcut.save()

Leia o alvo de um atalho usando Python (via WSH)

import sys
import win32com.client 

shell = win32com.client.Dispatch("WScript.Shell")
shortcut = shell.CreateShortCut("t:\\test.lnk")
print(shortcut.Targetpath)

Answer 2

Basicamente chamar a API do Windows diretamente. Aqui está um bom exemplo encontrado após pesquisando:

import os, sys
import pythoncom
from win32com.shell import shell, shellcon

shortcut = pythoncom.CoCreateInstance (
  shell.CLSID_ShellLink,
  None,
  pythoncom.CLSCTX_INPROC_SERVER,
  shell.IID_IShellLink
)
desktop_path = shell.SHGetFolderPath (0, shellcon.CSIDL_DESKTOP, 0, 0)
shortcut_path = os.path.join (desktop_path, "python.lnk")
persist_file = shortcut.QueryInterface (pythoncom.IID_IPersistFile)
persist_file.Load (shortcut_path)

shortcut.SetDescription ("Updated Python %s" % sys.version)
mydocs_path = shell.SHGetFolderPath (0, shellcon.CSIDL_PERSONAL, 0, 0)
shortcut.SetWorkingDirectory (mydocs_path)

persist_file.Save (shortcut_path, 0)

Esta é a partir http://timgolden.me.uk/python /win32_how_do_i/create-a-shortcut.html .

Você pode procurar por "IShellLink python" para outros exemplos.

Além disso, a referência API também ajuda: http: / /msdn.microsoft.com/en-us/library/bb774950(VS.85).aspx

Answer 3

Como alternativa, você pode tentar usar SHGetFolderPath () . O trabalho seguinte força de código, mas eu não estou em uma máquina Windows agora, então eu não posso testá-lo.

import ctypes

shell32 = ctypes.windll.shell32

# allocate MAX_PATH bytes in buffer
video_folder_path = ctypes.create_string_buffer(260)

# 0xE is CSIDL_MYVIDEO
# 0 is SHGFP_TYPE_CURRENT
# If you want a Unicode path, use SHGetFolderPathW instead
if shell32.SHGetFolderPathA(None, 0xE, None, 0, video_folder_path) >= 0:
    # success, video_folder_path now contains the correct path
else:
    # error

Answer 4

Eu sei que esta é uma discussão mais velhos, mas eu sinto que não há muita informação sobre o método que usa a especificação de destino como observado na pergunta original.

Meu implementação destino do atalho não poderia usar o win32com módulo e depois de muita pesquisa, decidi vir para cima com a minha própria. Nada mais parecia realizar o que eu necessário nas minhas restrições. Esperemos que isto irá ajudar outras pessoas na mesma situação.

Ele usa a estrutura binária Microsoft forneceu para MS-SHLLINK .

import struct

path = 'myfile.txt.lnk'    
target = ''

with open(path, 'rb') as stream:
    content = stream.read()
    # skip first 20 bytes (HeaderSize and LinkCLSID)
    # read the LinkFlags structure (4 bytes)
    lflags = struct.unpack('I', content[0x14:0x18])[0]
    position = 0x18
    # if the HasLinkTargetIDList bit is set then skip the stored IDList 
    # structure and header
    if (lflags & 0x01) == 1:
        position = struct.unpack('H', content[0x4C:0x4E])[0] + 0x4E
    last_pos = position
    position += 0x04
    # get how long the file information is (LinkInfoSize)
    length = struct.unpack('I', content[last_pos:position])[0]
    # skip 12 bytes (LinkInfoHeaderSize, LinkInfoFlags, and VolumeIDOffset)
    position += 0x0C
    # go to the LocalBasePath position
    lbpos = struct.unpack('I', content[position:position+0x04])[0]
    position = last_pos + lbpos
    # read the string at the given position of the determined length
    size= (length + last_pos) - position - 0x02
    temp = struct.unpack('c' * size, content[position:position+size])
    target = ''.join([chr(ord(a)) for a in temp])

Answer 5

Eu também percebo esta questão é antiga, mas eu encontrei as respostas para ser mais relevante para a minha situação.

A resposta de como Jared, eu também não poderia usar o win32com módulo. Assim, o uso da estrutura binária de MS-SHLLINK de Jared me pegou parte do o caminho até lá. Eu precisava de atalhos de leitura no Windows e no Linux, onde os atalhos são criados em um compartilhamento de samba pelo Windows. implementação de Jared não funcionou para mim, acho que só porque eu encontrei algumas variações diferentes no formato de atalho. Mas, ele me deu a começar eu precisava (graças Jared).

Então, aqui está uma classe chamada MSShortcut que se expande na abordagem de Jared. No entanto, a aplicação seja apenas Python3.4 e acima, devido ao uso de alguns pathlib recursos adicionados no Python3.4

#!/usr/bin/python3

# Link Format from MS: https://msdn.microsoft.com/en-us/library/dd871305.aspx
# Need to be able to read shortcut target from .lnk file on linux or windows.
# Original inspiration from: http://stackoverflow.com/questions/397125/reading-the-target-of-a-lnk-file-in-python

from pathlib import Path, PureWindowsPath
import struct, sys, warnings

if sys.hexversion < 0x03040000:
    warnings.warn("'{}' module requires python3.4 version or above".format(__file__), ImportWarning)


# doc says class id = 
#    00021401-0000-0000-C000-000000000046
# requiredCLSID = b'\x00\x02\x14\x01\x00\x00\x00\x00\xC0\x00\x00\x00\x00\x00\x00\x46'
# Actually Getting: 
requiredCLSID   = b'\x01\x14\x02\x00\x00\x00\x00\x00\xC0\x00\x00\x00\x00\x00\x00\x46'  # puzzling

class ShortCutError(RuntimeError):
    pass


class MSShortcut():
    """
    interface to Microsoft Shortcut Objects.  Purpose:
    - I need to be able to get the target from a samba shared on a linux machine
    - Also need to get access from a Windows machine.
    - Need to support several forms of the shortcut, as they seem be created differently depending on the 
      creating machine.
    - Included some 'flag' types in external interface to help test differences in shortcut types

    Args:
        scPath (str): path to shortcut

    Limitations:
        - There are some omitted object properties in the implementation. 
          Only implemented / tested enough to recover the shortcut target information. Recognized omissions:
          - LinkTargetIDList
          - VolumeId structure (if captured later, should be a separate class object to hold info)
          - Only captured environment block from extra data 
        - I don't know how or when some of the shortcut information is used, only captured what I recognized, 
          so there may be bugs related to use of the information
        - NO shortcut update support (though might be nice)
        - Implementation requires python 3.4 or greater
        - Tested only with Unicode data on a 64bit little endian machine, did not consider potential endian issues

    Not Debugged:
        - localBasePath - didn't check if parsed correctly or not.
        - commonPathSuffix
        - commonNetworkRelativeLink

    """

    def __init__(self, scPath):
        """
        Parse and keep shortcut properties on creation
        """
        self.scPath = Path(scPath)

        self._clsid = None
        self._lnkFlags = None
        self._lnkInfoFlags = None
        self._localBasePath = None
        self._commonPathSuffix = None
        self._commonNetworkRelativeLink = None
        self._name = None
        self._relativePath = None
        self._workingDir = None
        self._commandLineArgs = None
        self._iconLocation = None
        self._envTarget = None

        self._ParseLnkFile(self.scPath)  


    @property
    def clsid(self): 
        return self._clsid

    @property
    def lnkFlags(self): 
        return self._lnkFlags

    @property
    def lnkInfoFlags(self): 
        return self._lnkInfoFlags

    @property
    def localBasePath(self): 
        return self._localBasePath

    @property
    def commonPathSuffix(self): 
        return self._commonPathSuffix

    @property
    def commonNetworkRelativeLink(self): 
        return self._commonNetworkRelativeLink

    @property
    def name(self): 
        return self._name    

    @property
    def relativePath(self): 
        return self._relativePath    

    @property
    def workingDir(self): 
        return self._workingDir    

    @property
    def commandLineArgs(self): 
        return self._commandLineArgs    

    @property
    def iconLocation(self): 
        return self._iconLocation    

    @property
    def envTarget(self): 
        return self._envTarget    


    @property
    def targetPath(self):
        """
        Args:
            woAnchor (bool): remove the anchor (\\server\path or drive:) from returned path.

        Returns:
            a libpath PureWindowsPath object for combined workingDir/relative path
            or the envTarget

        Raises:
            ShortCutError when no target path found in Shortcut
        """
        target = None
        if self.workingDir:
            target = PureWindowsPath(self.workingDir)
            if self.relativePath:
                target = target / PureWindowsPath(self.relativePath)
            else: target = None

        if not target and self.envTarget:
            target = PureWindowsPath(self.envTarget)

        if not target:
            raise ShortCutError("Unable to retrieve target path from MS Shortcut: shortcut = {}"
                               .format(str(self.scPath)))  

        return target    

    @property
    def targetPathWOAnchor(self):
        tp = self.targetPath
        return tp.relative_to(tp.anchor)




    def _ParseLnkFile(self, lnkPath):        
        with lnkPath.open('rb') as f:
            content = f.read()

            # verify size  (4 bytes)
            hdrSize = struct.unpack('I', content[0x00:0x04])[0]
            if hdrSize != 0x4C:
                raise ShortCutError("MS Shortcut HeaderSize = {}, but required to be = {}: shortcut = {}"
                                   .format(hdrSize, 0x4C, str(lnkPath)))

            # verify LinkCLSID id (16 bytes)            
            self._clsid = bytes(struct.unpack('B'*16, content[0x04:0x14]))
            if self._clsid != requiredCLSID:
                raise ShortCutError("MS Shortcut ClassID = {}, but required to be = {}: shortcut = {}"
                                   .format(self._clsid, requiredCLSID, str(lnkPath)))        

            # read the LinkFlags structure (4 bytes)
            self._lnkFlags = struct.unpack('I', content[0x14:0x18])[0]
            #logger.debug("lnkFlags=0x%0.8x" % self._lnkFlags)
            position = 0x4C

            # if HasLinkTargetIDList bit, then position to skip the stored IDList structure and header
            if (self._lnkFlags & 0x01):
                idListSize = struct.unpack('H', content[position:position+0x02])[0]
                position += idListSize + 2

            # if HasLinkInfo, then process the linkinfo structure  
            if (self._lnkFlags & 0x02):
                (linkInfoSize, linkInfoHdrSize, self._linkInfoFlags, 
                 volIdOffset, localBasePathOffset, 
                 cmnNetRelativeLinkOffset, cmnPathSuffixOffset) = struct.unpack('IIIIIII', content[position:position+28])

                # check for optional offsets
                localBasePathOffsetUnicode = None
                cmnPathSuffixOffsetUnicode = None
                if linkInfoHdrSize >= 0x24:
                    (localBasePathOffsetUnicode, cmnPathSuffixOffsetUnicode) = struct.unpack('II', content[position+28:position+36])

                #logger.debug("0x%0.8X" % linkInfoSize)
                #logger.debug("0x%0.8X" % linkInfoHdrSize)
                #logger.debug("0x%0.8X" % self._linkInfoFlags)
                #logger.debug("0x%0.8X" % volIdOffset)
                #logger.debug("0x%0.8X" % localBasePathOffset)
                #logger.debug("0x%0.8X" % cmnNetRelativeLinkOffset)
                #logger.debug("0x%0.8X" % cmnPathSuffixOffset)
                #logger.debug("0x%0.8X" % localBasePathOffsetUnicode)
                #logger.debug("0x%0.8X" % cmnPathSuffixOffsetUnicode)

                # if info has a localBasePath
                if (self._linkInfoFlags & 0x01):
                    bpPosition = position + localBasePathOffset

                    # not debugged - don't know if this works or not
                    self._localBasePath = UnpackZ('z', content[bpPosition:])[0].decode('ascii')
                    #logger.debug("localBasePath: {}".format(self._localBasePath))

                    if localBasePathOffsetUnicode:
                        bpPosition = position + localBasePathOffsetUnicode
                        self._localBasePath = UnpackUnicodeZ('z', content[bpPosition:])[0]
                        self._localBasePath = self._localBasePath.decode('utf-16')               
                        #logger.debug("localBasePathUnicode: {}".format(self._localBasePath))

                # get common Path Suffix
                cmnSuffixPosition = position + cmnPathSuffixOffset               
                self._commonPathSuffix = UnpackZ('z', content[cmnSuffixPosition:])[0].decode('ascii')
                #logger.debug("commonPathSuffix: {}".format(self._commonPathSuffix))
                if cmnPathSuffixOffsetUnicode:
                    cmnSuffixPosition = position + cmnPathSuffixOffsetUnicode
                    self._commonPathSuffix = UnpackUnicodeZ('z', content[cmnSuffixPosition:])[0]
                    self._commonPathSuffix = self._commonPathSuffix.decode('utf-16')               
                    #logger.debug("commonPathSuffix: {}".format(self._commonPathSuffix))


                # check for CommonNetworkRelativeLink
                if (self._linkInfoFlags & 0x02):
                    relPosition = position + cmnNetRelativeLinkOffset
                    self._commonNetworkRelativeLink = CommonNetworkRelativeLink(content, relPosition)

                position += linkInfoSize 

            # If HasName
            if (self._lnkFlags & 0x04):
                (position, self._name) = self.readStringObj(content, position)
                #logger.debug("name: {}".format(self._name))     

            # get relative path string
            if (self._lnkFlags & 0x08):
                (position, self._relativePath) = self.readStringObj(content, position)
                #logger.debug("relPath='{}'".format(self._relativePath))

            # get working dir string
            if (self._lnkFlags & 0x10):
                (position, self._workingDir) = self.readStringObj(content, position)
                #logger.debug("workingDir='{}'".format(self._workingDir))

            # get command line arguments
            if (self._lnkFlags & 0x20):
                (position, self._commandLineArgs) = self.readStringObj(content, position)
                #logger.debug("commandLineArgs='{}'".format(self._commandLineArgs))

            # get icon location
            if (self._lnkFlags & 0x40):
                (position, self._iconLocation) = self.readStringObj(content, position)
                #logger.debug("iconLocation='{}'".format(self._iconLocation))

            # look for environment properties             
            if (self._lnkFlags & 0x200):
                while True:
                    size = struct.unpack('I', content[position:position+4])[0]
                    #logger.debug("blksize=%d" % size)
                    if size==0: break

                    signature = struct.unpack('I', content[position+4:position+8])[0]
                    #logger.debug("signature=0x%0.8x" % signature)     

                    # EnvironmentVariableDataBlock          
                    if signature == 0xA0000001:  

                        if (self._lnkFlags & 0x80): # unicode
                            self._envTarget = UnpackUnicodeZ('z', content[position+268:])[0]
                            self._envTarget = self._envTarget.decode('utf-16')
                        else:
                            self._envTarget = UnpackZ('z', content[position+8:])[0].decode('ascii')

                        #logger.debug("envTarget='{}'".format(self._envTarget))

                    position += size


    def readStringObj(self, scContent, position):
        """ 
        returns:
            tuple: (newPosition, string)
        """
        strg = ''
        size = struct.unpack('H', scContent[position:position+2])[0]
        #logger.debug("workingDirSize={}".format(size))
        if (self._lnkFlags & 0x80): # unicode
            size *= 2
            strg = struct.unpack(str(size)+'s', scContent[position+2:position+2+size])[0]
            strg = strg.decode('utf-16')               
        else:
            strg = struct.unpack(str(size)+'s', scContent[position+2:position+2+size])[0].decode('ascii')
        #logger.debug("strg='{}'".format(strg))
        position += size + 2 # 2 bytes to account for CountCharacters field

        return (position, strg)




class CommonNetworkRelativeLink():

    def __init__(self, scContent, linkContentPos):

        self._networkProviderType = None
        self._deviceName = None
        self._netName = None

        (linkSize, flags, netNameOffset, 
         devNameOffset, self._networkProviderType) = struct.unpack('IIIII', scContent[linkContentPos:linkContentPos+20])

        #logger.debug("netnameOffset = {}".format(netNameOffset))
        if netNameOffset > 0x014:
            (netNameOffsetUnicode, devNameOffsetUnicode) = struct.unpack('II', scContent[linkContentPos+20:linkContentPos+28])
            #logger.debug("netnameOffsetUnicode = {}".format(netNameOffsetUnicode))
            self._netName = UnpackUnicodeZ('z', scContent[linkContentPos+netNameOffsetUnicode:])[0]
            self._netName = self._netName.decode('utf-16')  
            self._deviceName = UnpackUnicodeZ('z', scContent[linkContentPos+devNameOffsetUnicode:])[0]
            self._deviceName = self._deviceName.decode('utf-16')               
        else:
            self._netName = UnpackZ('z', scContent[linkContentPos+netNameOffset:])[0].decode('ascii')
            self._deviceName = UnpackZ('z', scContent[linkContentPos+devNameOffset:])[0].decode('ascii')

    @property    
    def deviceName(self):
        return self._deviceName

    @property    
    def netName(self):
        return self._netName

    @property    
    def networkProviderType(self):
        return self._networkProviderType



def UnpackZ (fmt, buf) :
    """
    Unpack Null Terminated String
    """
    #logger.debug(bytes(buf))

    while True :
        pos = fmt.find ('z')
        if pos < 0 :
            break
        z_start = struct.calcsize (fmt[:pos])
        z_len = buf[z_start:].find(b'\0')
        #logger.debug(z_len)
        fmt = '%s%dsx%s' % (fmt[:pos], z_len, fmt[pos+1:])
        #logger.debug("fmt='{}', len={}".format(fmt, z_len))
    fmtlen = struct.calcsize(fmt)
    return struct.unpack (fmt, buf[0:fmtlen])


def UnpackUnicodeZ (fmt, buf) :
    """
    Unpack Null Terminated String
    """
    #logger.debug(bytes(buf))
    while True :
        pos = fmt.find ('z')
        if pos < 0 :
            break
        z_start = struct.calcsize (fmt[:pos])
        # look for null bytes by pairs
        z_len = 0
        for i in range(z_start,len(buf),2):
            if buf[i:i+2] == b'\0\0':
                z_len = i-z_start
                break

        fmt = '%s%dsxx%s' % (fmt[:pos], z_len, fmt[pos+1:])
       # logger.debug("fmt='{}', len={}".format(fmt, z_len))
    fmtlen = struct.calcsize(fmt)
    return struct.unpack (fmt, buf[0:fmtlen])

Espero que isso ajude os outros também. Graças