From b8860ef6150bb6b7f0770180e9471b3c80aa8ffc Mon Sep 17 00:00:00 2001
From: benoitc <bchesneau@gmail.com>
Date: Wed, 20 Nov 2019 00:19:07 +0100
Subject: [PATCH 1/2] fix gunicorn when used with musl libc

find_library('c') doesn't work in Alpine Linux. This happen because musl has a simpler implementation of libc.

This patch fix it by extending ctypes.util.find_library to search the libs using LD_LIBRARY_PATH.

Patch is based on https://github.com/python/cpython/commit/e3f67780aab24401a50af64e688d38c24ee41ad0

See also https://bugs.python.org/issue21622

fix #2160
---
 gunicorn/socketfromfd.py |  2 +-
 gunicorn/util.py         | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/gunicorn/socketfromfd.py b/gunicorn/socketfromfd.py
index 69299200..74f6503d 100644
--- a/gunicorn/socketfromfd.py
+++ b/gunicorn/socketfromfd.py
@@ -12,7 +12,7 @@ import socket
 import sys
 import platform
 
-from ctypes.util import find_library
+from .util import find_library
 
 __all__ = ('fromfd',)
 
diff --git a/gunicorn/util.py b/gunicorn/util.py
index 8ccaf9b3..233094cc 100644
--- a/gunicorn/util.py
+++ b/gunicorn/util.py
@@ -3,6 +3,7 @@
 # This file is part of gunicorn released under the MIT license.
 # See the NOTICE for more information.
 import ast
+import ctypes.util
 import email.utils
 import errno
 import fcntl
@@ -635,3 +636,32 @@ def bytes_to_str(b):
 
 def unquote_to_wsgi_str(string):
     return urllib.parse.unquote_to_bytes(string).decode('latin-1')
+
+
+def _findWalk_ldpath(name):
+    def _is_elf(filepath):
+        try:
+            with open(filepath, 'rb') as fh:
+                return fh.read(4) == b'\x7fELF'
+        except:
+            return False
+    from glob import glob
+    if os.path.isabs(name):
+        return name
+
+    # search LD_LIBRARY_PATH list
+    paths = os.environ.get('LD_LIBRARY_PATH', '').split(':')
+    if paths:
+        for d in paths:
+            f = os.path.join(d, name)
+            if _is_elf(f):
+                return os.path.basename(f)
+            prefix = os.path.join(d, 'lib'+name)
+            for suffix in ['.so', '.so.*']:
+                for f in glob('{0}{1}'.format(prefix, suffix)):
+                    if _is_elf(f):
+                        return os.path.basename(f)
+
+
+def find_library(name):
+    return ctypes.util.find_library(name) or _findWalk_ldpath(name)

From d55c7cb01505a1c4db946ea76bac4aef04a248cf Mon Sep 17 00:00:00 2001
From: benoitc <bchesneau@gmail.com>
Date: Wed, 20 Nov 2019 21:36:01 +0100
Subject: [PATCH 2/2] fix lib discovery

LD_LIBRARY_PATH is sometimes empty, this change fix it.
Also test suffix with the "." as it seems to be an issue
---
 gunicorn/util.py | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/gunicorn/util.py b/gunicorn/util.py
index 233094cc..402123da 100644
--- a/gunicorn/util.py
+++ b/gunicorn/util.py
@@ -650,17 +650,19 @@ def _findWalk_ldpath(name):
         return name
 
     # search LD_LIBRARY_PATH list
-    paths = os.environ.get('LD_LIBRARY_PATH', '').split(':')
-    if paths:
-        for d in paths:
-            f = os.path.join(d, name)
-            if _is_elf(f):
-                return os.path.basename(f)
-            prefix = os.path.join(d, 'lib'+name)
-            for suffix in ['.so', '.so.*']:
-                for f in glob('{0}{1}'.format(prefix, suffix)):
-                    if _is_elf(f):
-                        return os.path.basename(f)
+    paths = ['/lib', '/usr/local/lib', '/usr/lib']
+    if 'LD_LIBRARY_PATH' in os.environ:
+        paths = os.environ['LD_LIBRARY_PATH'].split(':') + paths
+
+    for d in paths:
+        f = os.path.join(d, name)
+        if _is_elf(f):
+            return os.path.basename(f)
+        prefix = os.path.join(d, 'lib'+name)
+        for suffix in ['so', 'so.*']:
+            for f in glob('{0}.{1}'.format(prefix, suffix)):
+                if _is_elf(f):
+                    return os.path.basename(f)
 
 
 def find_library(name):