Merge pull request dsoprea#22 from dsoprea/brew_help

Added Brew tool.

libarchive/library.py

@@ -4,13 +4,48 @@
 import ctypes
 import ctypes.util
 
-_logger = logging.getLogger(__name__)
+_LOGGER = logging.getLogger(__name__)
 
-_FILEPATH = os.environ.get('LA_LIBRARY_FILEPATH', '')
-if _FILEPATH == '':
-    _FILEPATH = ctypes.util.find_library('libarchive')
-    if _FILEPATH is None:
-        _FILEPATH = 'libarchive.so'
+_LIBRARY_NAME = 'libarchive'
+_LIBRARY_FILENAME = 'libarchive.so'
 
-_logger.debug("Using library: [%s]", _FILEPATH)
+def find_and_load_library():
+    search_filepaths = []
+
+    # Search for the library using our own environment variable.
+
+    filepath = os.environ.get('LA_LIBRARY_FILEPATH', '')
+    if filepath != '':
+        search_filepaths.append(filepath)
+
+    # Search for the library using the well-defined system library search-path.
+
+    _SEARCH_PATH = os.environ.get('LD_LIBRARY_PATH', '')
+    if _SEARCH_PATH != '':
+        for path in _SEARCH_PATH.split(":"):
+            filepath = os.path.join(path, _LIBRARY_FILENAME)
+            search_filepaths.append(filepath)
+
+    # Search for our library using whatever search-path ctypes uses (not the same 
+    # as `LD_LIBRARY_PATH`).
+
+    filepath = ctypes.util.find_library(_LIBRARY_NAME)
+    if filepath is not None:
+        search_filepaths.append(filepath)
+
+    # Load the first one available.
+
+    found_filepath = None
+    for filepath in search_filepaths:
+        if os.path.exists(filepath) is True:
+            return filepath
+
+    # Fallback on the naively trying to load the filename.
+
+    _LOGGER.debug("Using default library file-path: [%s]", _LIBRARY_FILENAME)
+    return _LIBRARY_FILENAME
+
+_FILEPATH = find_and_load_library()
+
+_LOGGER.debug("Using library file-path: [%s]", _FILEPATH)
 libarchive = ctypes.cdll.LoadLibrary(_FILEPATH)

libarchive/log.py

@@ -0,0 +1,35 @@
+import sys
+import os
+import logging
+import logging.handlers
+
+logger = logging.getLogger()
+
+is_debug = bool(int(os.environ.get('DEBUG', '0')))
+
+if is_debug is True:
+    logger.setLevel(logging.DEBUG)
+else:
+    logger.setLevel(logging.INFO)
+
+format = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+formatter = logging.Formatter(format)
+
+ch = logging.StreamHandler()
+ch.setFormatter(formatter)
+logger.addHandler(ch)
+
+# TODO(dustin): This all does not work for a Linux system. Just omit the "address" parameter completely.
+if sys.platform == 'darwin':
+    address = '/var/run/syslog'
+elif os.path.exists('/dev/log'):
+    address = '/dev/log'
+else:
+    address = ('localhost', 514)
+
+ch = logging.handlers.SysLogHandler(
+        address, 
+        facility=logging.handlers.SysLogHandler.LOG_LOCAL0)
+
+ch.setFormatter(formatter)
+logger.addHandler(ch)

libarchive/resources/README.rst

@@ -1,5 +1,3 @@
-**To eliminate some problems with installation, the public API has been moved from the `libarchive` package to `libarchive.public`, and will be reflected in the next release. This is backwards-incompatible, but would otherwise prevent the install due to broken dependencies during install.**
-
 ------------
 Introduction
 ------------
@@ -34,6 +32,8 @@ Notes
     
 - Encryption is not currently supported since it's not supported in the underlying library (*libarchive*). Note `this inquiry <https://github.com/libarchive/libarchive/issues/579>`_ and the `wishlist item <https://github.com/libarchive/libarchive/wiki/WishList#encrypted-backup-support>`_.
 
+- OS X has a system version of `libarchive` that is very old. As a result, many users have encountered issues importing an alternate one. Specifically, often they install a different one via Brew but this will not be [sym]linked into the system like other packages. This is a precaution taken by Brew to prevent undefined behavior in the parts of OS X that depend on the factory version. In order to work around this, you should set `LD_LIBRARY_PATH` (or prepend if `LD_LIBRARY_PATH` is already defined) with the path of the location of the library version you want to use. You'll want to set this from your user-profile script (unless your environment can not support this and you need to prepend something like "LD_LIBRARY_PATH=/some/path" to the front of the command-line or set it via `os.environ` above where you import this package). A `tool <tools/brew_find_libarchive>`_ has been provided that will print the path of the first version of `libarchive` installed via Brew. Just copy-and-paste it. Thanks to @SkyLeach for discussing the issue and treatments.
+
 
 ---------
 Task List
@@ -160,6 +160,6 @@ To create an archive in memory from physical files::
 Testing
 -------
 
-*libarchive* uses [nose](https://nose.readthedocs.org) for testing::
+*libarchive* uses `nose <https://nose.readthedocs.org>`_ for testing::
 
     tests$ ./run.py

tests/run.py

@@ -3,12 +3,6 @@
 import sys
 sys.path.insert(0, '..')
 
-import os
-import os.path
 import nose
 
-mac_library_path = '/Users/dustin/build/libarchive/build/libarchive'
-if os.path.exists(mac_library_path) is True:
-    os.environ['DYLD_LIBRARY_PATH'] = mac_library_path
-
 nose.run()

tools/brew_find_libarchive

@@ -0,0 +1,28 @@
+#!/usr/bin/env python2.7
+
+import sys
+import os
+import json
+import subprocess
+
+command = ['brew', 'info', '--json=v1', 'libarchive']
+
+try:
+    result = subprocess.check_output(command)
+except Exception as e:
+    print("Could not lookup 'libarchive' package info: {0}".format(e.strerror))
+    sys.exit(1)
+
+info = json.loads(result)
+installed_versions = info[0]['installed']
+if len(installed_versions) == 0:
+    print("libarchive is not currently installed via Brew")
+    sys.exit(2)
+
+version = installed_versions[0]['version']
+
+command = ['brew', '--cellar', 'libarchive']
+package_path = subprocess.check_output(command)[:-1]
+
+library_path = os.path.join(package_path, version, 'lib')
+print(library_path)