Tests: test_settings_send_timeout improved.

Data length adjusts depending on socket buffer size when it's possible.

test/python/body_generate/wsgi.py

@@ -0,0 +1,6 @@
+def application(env, start_response):
+    length = env.get('HTTP_X_LENGTH', '10')
+    bytes = b'X' * int(length)
+
+    start_response('200', [('Content-Length', length)])
+    return [bytes]

test/test_settings.py

@@ -5,6 +5,7 @@ import time
 import pytest
 
 from unit.applications.lang.python import TestApplicationPython
+from unit.utils import sysctl
 
 
 class TestSettings(TestApplicationPython):
@@ -147,27 +148,35 @@ Connection: close
         assert resp['status'] == 200, 'status body read timeout update'
 
     def test_settings_send_timeout(self, temp_dir):
-        self.load('mirror')
+        self.load('body_generate')
 
-        data_len = 1048576
+        sysctl_out = sysctl()
+        values = re.findall(
+            r'net.core.[rw]mem_(?:max|default).*?(\d+)', sysctl_out
+        )
+        values = [int(v) for v in values]
+
+        data_len = 1048576 if len(values) == 0 else 10 * max(values)
 
         self.conf({'http': {'send_timeout': 1}}, 'settings')
 
         addr = temp_dir + '/sock'
 
-        self.conf({"unix:" + addr: {'application': 'mirror'}}, 'listeners')
+        self.conf(
+            {"unix:" + addr: {'application': 'body_generate'}}, 'listeners'
+        )
 
         sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
         sock.connect(addr)
 
-        req = """POST / HTTP/1.1
+        req = (
+            """GET / HTTP/1.1
 Host: localhost
-Content-Type: text/html
+X-Length: %d
-Content-Length: %d
 Connection: close
 
-""" % data_len + (
+"""
-            'X' * data_len
+            % data_len
         )
 
         sock.sendall(req.encode())

test/unit/utils.py

@@ -61,6 +61,17 @@ def findmnt():
     return out
 
 
+def sysctl():
+    try:
+        out = subprocess.check_output(
+            ['sysctl', '-a'], stderr=subprocess.STDOUT
+        ).decode()
+    except FileNotFoundError:
+        pytest.skip('requires sysctl')
+
+    return out
+
+
 def waitformount(template, wait=50):
     for i in range(wait):
         if findmnt().find(template) != -1: