When developing a desktop app using C++ (e.g. GeoDa) on Mac, one of the most painful work is to bundle your final program into a .App executable. One of the boring task in this work is to find and package all necessary depdendent libraries for your program, so it can not only just run on your Mac, but all other Macs.

I developed a npm module “mac-dependencies”, which is a javascript module to print and check the dependencies of an executable or dylib on Mac.

Based on this module, I plan to build a Desktop app to automatically create a .App executable or DMG for your C++ program.

mac-dependencies

Mac-dependencies is a node.js module to “walk” dependencies of an executable or dylib on Mac. It will automatically resolve the @executable_path, @rpath and @loader_path paths to find dependent libraries.

Users can use it to print the dependencies, check which dependencies were missing, and build a DMG by copying dependent libraries of an executable on Mac (see its usage in GeoDa build toolchain).

Usage

1. print_deps()

print_deps(file_path : String, {options : Dict}) : String

Example: ```javascript const macdep = require(‘mac-dependencies’);

macdep.print_deps(‘/usr/lib/libcurl.dylib’);

> Output:

└─ ✔ libcurl.dylib /usr/lib/libcurl.dylib ├─ ✔ libcrypto.42.dylib /usr/lib/libcrypto.42.dylib │ └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib ├─ ✔ libssl.44.dylib /usr/lib/libssl.44.dylib │ ├─ ✔ libcrypto.42.dylib /usr/lib/libcrypto.42.dylib │ │ └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib │ └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib ├─ ✔ libapple_nghttp2.dylib /usr/lib/libapple_nghttp2.dylib │ └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib ├─ ✔ libz.1.dylib /usr/lib/libz.1.dylib │ └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib

#### 1.1 Check missing dependencies

Any missing dependencies will be highlighed in the output with a "question mark" icon ❓.

> Example:
```javascript
macdep.print_deps('/Users/xun/test.dylib');

Output:

└─ ✔ test.dylib /Users/xun/test.dylib
   ├─ ❓ libpng16.16.dylib @rpath/libpng16.16.dylib
   └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib

1.2 Option: search_dirs

For missing dependencies, one can specify a list of search dirs as an option to tell the program to search any missing dependencies.

Example:

var opts = {"search_dirs" : ["/usr/lib", "/usr/local/lib"]};
macdep.print_deps('/Users/xun/test.dylib', opts);

Output:

└─ ✔ test.dylib /Users/xun/test.dylib
   ├─ ✔ libpng16.16.dylib /usr/local/lib/libpng16.16.dylib
   └─ ✔ libSystem.B.dylib /usr/lib/libSystem.B.dylib

1.3 Option: system_dirs

Default value: [‘/usr/lib/system’, ‘/Library/System’]

One can specify a list of system dirs as an option to tell the program to ignore when searching dependencies.

Example:

var opts = {
    "system_dirs" : ["/usr/lib"], 
    "search_dirs" : ["/usr/lib", "/usr/local/lib"]
};
macdep.print_deps('/Users/xun/test.dylib', opts);

Output:

└─ ✔ test.dylib /Users/xun/test.dylib
   └─ ✔ libpng16.16.dylib /usr/local/lib/libpng16.16.dylib

2. get_deps()

get_deps(file_path : String, {options : dict}) : object

Example:

const macdep = require('mac-dependencies');

var dep = macdep.get_deps('/usr/lib/libcurl.dylib');

Returns a javascript object representing the tree structure of dependencies. For example:

dep {
   // attributes
   this.file_path = '/Users/xun/test.dylib', // 
   this.file_name = 'test.lib', //
   this.is_system = false, //
   this.is_valid = true, //
   this.dependencies = ['/usr/local/lib/libpng16.16.dylib', // a list of dependencies as dep objects
                        '/usr/lib/libSystem.B.dylib'], 
   this.executable_path = '/Users/xun',
   this.loader_path = '/Users/xun',
   this.r_path = undefined
}

One can traverse this tree structure starting from the return object by get_deps() function, and looping its children in dependencies[].

const macdep = require('mac-dependencies');

var dep = macdep.get_deps('/usr/lib/libcurl.dylib');
if (dep) {
   var stack = [dep];
   console.log("Print depdencies of ", dep.file_path);
   while (stack.length > 0) {
      var el = stack.pop();
      for (var i = 0; i < dep.dependencies.length; i++) {
         stack.push(dep.dependencies[i]);
      }
   }
}