Using otool (recursively) to find shared libraries needed by an app

Question

I have a Cocoa app that uses otool to find required shared libraries that an app needs to function properly. For example, say I run otool -L on an app that uses QTKit.framework. I get a list of the shared libraries used by the program (including the basic frameworks like Cocoa.framework and AppKit.framework):

/System/Library/Frameworks/QTKit.framework/Versions/A/QTKit (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 476.0.0)
    /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit (compatibility version 45.0.0, current version 949.0.0)

..... and so on for a bunch of other frameworks

Which shows that the app uses QTKit.framework. However if I use "otool -L" again on the binary for QTKit.framework (/System/Library/Frameworks/QTKit.framework/Versions/A/QTKit) I get this:

/System/Library/Frameworks/QTKit.framework/Versions/A/QTKit (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/AudioToolbox.framework/Versions/A/AudioToolbox (compatibility version 1.0.0, current version 1.0.0)
/System/Library/PrivateFrameworks/CoreMedia.framework/Versions/A/CoreMedia (compatibility version 1.0.0, current version 1.0.0)
/System/Library/PrivateFrameworks/MediaToolbox.framework/Versions/A/MediaToolbox (compatibility version 1.0.0, current version 1.0.0)
/System/Library/PrivateFrameworks/VideoToolbox.framework/Versions/A/VideoToolbox (compatibility version 1.0.0, current version 1.0.0)
/System/Library/PrivateFrameworks/CoreMediaIOServices.framework/Versions/A/CoreMediaIOServices (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/Foundation.framework/Versions/C/Foundation (compatibility version 300.0.0, current version 751.0.0)
/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit (compatibility version 45.0.0, current version 1038.0.0)
/System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
/System/Library/Frameworks/QuickTime.framework/Versions/A/QuickTime (compatibility version 1.0.0, current version 1584.0.0)
/System/Library/Frameworks/CoreAudio.framework/Versions/A/CoreAudio (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore (compatibility version 1.2.0, current version 1.6.0)
/System/Library/Frameworks/IOSurface.framework/Versions/A/IOSurface (compatibility version 1.0.0, current version 1.0.0)
/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox (compatibility version 1.0.0, current version 435.0.0)
/usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 7.9.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 123.0.0)
/usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 227.0.0)
/System/Library/Frameworks/CoreServices.framework/Versions/A/CoreServices (compatibility version 1.0.0, current version 44.0.0)
/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 550.0.0)
/System/Library/Frameworks/ApplicationServices.framework/Versions/A/ApplicationServices (compatibility version 1.0.0, current version 38.0.0)
/System/Library/Frameworks/CoreVideo.framework/Versions/A/CoreVideo (compatibility version 1.2.0, current version 1.6.0)

That shows a load more frameworks that the original otool output on the app binary showed. Is there a way to have otool run recursively, meaning it grabs the frameworks that the app needs, then goes in and searches each of those frameworks for dependencies?

Answer 1

No, you'll have to run otool repeatedly, or incorporate its parsing code (here). Don't forget about handling @executable_path.

Here it is in Python (without @executable_path, canonicalization, or filenames-with-spaces supported), since this was easier than trying to debug pseudocode:

import subprocess

def otool(s):
    o = subprocess.Popen(['/usr/bin/otool', '-L', s], stdout=subprocess.PIPE)
    for l in o.stdout:
        if l[0] == '\t':
            yield l.split(' ', 1)[0][1:]

need = set(['/Applications/iTunes.app/Contents/MacOS/iTunes'])
done = set()

while need:
    needed = set(need)
    need = set()
    for f in needed:
        need.update(otool(f))
    done.update(needed)
    need.difference_update(done)

for f in sorted(done):
    print f

Answer 2

Here's my solution that I use to fix macdeployqt's output when using Homebrew-installed libraries. What I've found is that macdeployqt does a good job of putting the dylibs in the Framework folder, but it fails to fix the paths.

https://github.com/jveitchmichaelis/deeplabel/blob/master/fix_paths_mac.py

I've modified Nicholas' script to be a bit more usable - it corrects for @executable_path, @rpath and @loader_path. This isn't exactly production code, but it has let me run apps on other Macs without any dependencies already installed.

Run with: python fix_paths_mac.py ./path/to/your.app/Contents/MacOS/your_exe. i.e. point it to the binary inside an app package and it'll figure out the rest.

I've assumed that most of the problems come from stuff linked to /usr/local. So if the code detects that there's a dependency that points to a file in /usr/local, it'll fix the paths appropriately. You could change the pass statement to copy in a file if it's not in the Frameworks folder, but I've not encountered a situation where there's a missing dylib, it's just linked wrong.

import subprocess
import os
import sys
from shutil import copyfile

executable = sys.argv[1]
app_folder = os.path.join(*executable.split('/')[:-3])
content_folder = os.path.join(app_folder, "Contents")
framework_path = os.path.join(content_folder, "Frameworks")

print(executable)
print("Working in {} ".format(app_folder))

def file_in_folder(file, folder):
    return os.path.exists(os.path.join(folder, file))

def otool(s):
    o = subprocess.Popen(['/usr/bin/otool', '-L', s], stdout=subprocess.PIPE)

    for l in o.stdout:
        l = l.decode()

        if l[0] == '\t':
            path = l.split(' ', 1)[0][1:]

            if "@executable_path" in path:
                path = path.replace("@executable_path", "")
                # fudge here to strip /../ from the start of the path.
                path = os.path.join(content_folder, path[4:])

            if "@loader_path" in path:
                path = path.replace("@loader_path", framework_path)

            if "@rpath" in path:
                path = path.replace("@rpath", framework_path)

            dependency_dylib_name = os.path.split(path)[-1]

            if "usr/local" in path:
                if app_folder in s:

                    print("Warning: {} depends on {}".format(s, path))

                    if file_in_folder(dependency_dylib_name, framework_path):
                        print("Dependent library {} is already in framework folder".format(dependency_dylib_name))

                        print("Running install name tool to fix {}.".format(s))

                        if dependency_dylib_name == os.path.split(s)[-1]:
                            _ = subprocess.Popen(['install_name_tool', '-id', os.path.join("@loader_path", dependency_dylib_name), s], stdout=subprocess.PIPE)

                        _ = subprocess.Popen(['install_name_tool', '-change', path, os.path.join("@loader_path", dependency_dylib_name), s], stdout=subprocess.PIPE)
                else:
                    # Potentially you could copy in the offending dylib here.
                    pass

            yield path

need = set([executable])
done = set()

while need:
    needed = set(need)
    need = set()
    for f in needed:
        need.update(otool(f))
    done.update(needed)
    need.difference_update(done)