Merge branch 'devel'2_4_2

1 files changed, 75 insertions, 0 deletions

diff --git a/scripts/ticket58.py b/scripts/ticket58.py
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+"""
+A script to reproduce the race condition described in ticket #58
+
+from https://bugzilla.redhat.com/show_bug.cgi?id=711095
+
+Results in the error:
+
+  python: Modules/gcmodule.c:277: visit_decref: Assertion `gc->gc.gc_refs != 0'
+  failed.
+
+on unpatched library.
+"""
+
+import threading
+import gc
+import time
+
+import psycopg2
+from StringIO import StringIO
+
+done = 0
+
+class GCThread(threading.Thread):
+    # A thread that sits in an infinite loop, forcing the garbage collector
+    # to run
+    def run(self):
+        global done
+        while not done:
+            gc.collect()
+            time.sleep(0.1) # give the other thread a chance to run
+
+gc_thread = GCThread()
+
+
+# This assumes a pre-existing db named "test", with:
+#   "CREATE TABLE test (id serial PRIMARY KEY, num integer, data varchar);"
+
+conn = psycopg2.connect("dbname=test user=postgres")
+cur = conn.cursor()
+
+# Start the other thread, running the GC regularly
+gc_thread.start()
+
+# Now do lots of "cursor.copy_from" calls:
+print "copy_from"
+for i in range(1000):
+    f = StringIO("42\tfoo\n74\tbar\n")
+    cur.copy_from(f, 'test', columns=('num', 'data'))
+    # Assuming the other thread gets a chance to run during this call, expect a
+    # build of python (with assertions enabled) to bail out here with:
+    #    python: Modules/gcmodule.c:277: visit_decref: Assertion `gc->gc.gc_refs != 0' failed.
+
+# Also exercise the copy_to code path
+print "copy_to"
+cur.execute("truncate test")
+f = StringIO("42\tfoo\n74\tbar\n")
+cur.copy_from(f, 'test', columns=('num', 'data'))
+for i in range(1000):
+    f = StringIO()
+    cur.copy_to(f, 'test', columns=('num', 'data'))
+
+# And copy_expert too
+print "copy_expert"
+cur.execute("truncate test")
+for i in range(1000):
+    f = StringIO("42\tfoo\n74\tbar\n")
+    cur.copy_expert("copy test to stdout", f)
+
+# Terminate the GC thread's loop:
+done = 1
+
+cur.close()
+conn.close()
+
+