Link mudraw binary to bundled libraries on Mac OS X

osx/macosx-builder.py

@@ -93,6 +93,11 @@ MuPDF
     Required for PDF support in OpenLP. Install using macports, or use the
     '--mudraw-bin' option of this script to point to the mudraw binary.
 
+MachOLib
+    Python library to analyze and edit Mach-O headers, the executable format
+    used by Mac OS X. Used to relink the mudraw binary from MuPDF to the bundled
+    libraries. Install using macports or pip.
+
 config.ini.default
     The configuration file contains settings of the version string to include
     in the bundle as well as directory and file settings for different
@@ -126,6 +131,9 @@ from subprocess import Popen, PIPE
 from configparser import ConfigParser
 from argparse import ArgumentParser
 
+from macholib.MachO import MachO
+from macholib.util import flipwritable, in_system_path
+
 
 def _which(command):
     """
@@ -451,9 +459,58 @@ class MacosxBuilder(object):
         self._print_verbose('... mudraw')
         if self.mudraw_bin and os.path.isfile(self.mudraw_bin):
             copy(os.path.join(self.mudraw_bin), os.path.join(self.dist_path, 'mudraw'))
+            self.relink_mudraw()
         else:
             self._print('... WARNING: mudraw not found')
 
+    def relink_mudraw(self):
+        """
+        Relink mudraw to bundled libraries
+        """
+        self._print('Linking mudraw with bundled libraries...')
+        libname = os.path.join(self.dist_path, 'mudraw')
+        distname = os.path.relpath(self.dist_path, libname)
+        self._print_verbose('... mudraw path %s', libname)
+
+        # Determine how many directories up is the directory with shared
+        # dynamic libraries. '../'
+        # E.g.  ./qt4_plugins/images/ -> ./../../
+        parent_dir = ''
+        # Check if distname is not only base filename.
+        if os.path.dirname(distname):
+            parent_level = len(os.path.dirname(distname).split(os.sep))
+            parent_dir = parent_level * (os.pardir + os.sep)
+
+        def match_func(pth):
+            """
+            For system libraries leave path unchanged.
+            """
+            # Match non system dynamic libraries.
+            if not in_system_path(pth):
+                # Use relative path to dependend dynamic libraries bases on
+                # location of the executable.
+                pth = os.path.join('@loader_path', parent_dir, os.path.basename(pth))
+                self._print_verbose('... %s', pth)
+                return pth
+
+        # Rewrite mach headers with @loader_path.
+        dll = MachO(libname)
+        dll.rewriteLoadCommands(match_func)
+
+        # Write changes into file.
+        # Write code is based on macholib example.
+        try:
+            self._print_verbose('... writing new library paths')
+            f = open(dll.filename, 'rb+')
+            for header in dll.headers:
+                f.seek(0)
+                dll.write(f)
+            f.seek(0, 2)
+            f.flush()
+            f.close()
+        except Exception:
+            pass
+
     def update_translations(self):
         """
         Update the translations.