Add //third_party/sqlite to dirs_to_snapshot, remove net_sql.patch

third_party/sqlite/sqlite-src-3070603/test/thread004.test

Index: third_party/sqlite/sqlite-src-3070603/test/thread004.test
diff --git a/third_party/sqlite/sqlite-src-3070603/test/thread004.test b/third_party/sqlite/sqlite-src-3070603/test/thread004.test
new file mode 100644
index 0000000000000000000000000000000000000000..b2adc460d008a85446bab42c65e7643a70a78fde
--- /dev/null
+++ b/third_party/sqlite/sqlite-src-3070603/test/thread004.test
@@ -0,0 +1,79 @@
+# 2009 February 26
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# $Id: thread004.test,v 1.3 2009/06/05 17:09:12 drh Exp $
+
+set testdir [file dirname $argv0]
+
+source $testdir/tester.tcl
+if {[run_thread_tests]==0} { finish_test ; return }
+ifcapable !shared_cache {
+  finish_test
+  return
+}
+if { [info commands sqlite3_table_column_metadata] eq "" } {
+  finish_test
+  return
+}
+
+# Use shared-cache mode for this test.
+# 
+db close
+set ::enable_shared_cache [sqlite3_enable_shared_cache]
+sqlite3_enable_shared_cache 1
+
+# Create a table in database test.db
+#
+sqlite3 db test.db
+do_test thread004-1.1 {
+  execsql { CREATE TABLE t1(a, b, c) }
+} {}
+
+do_test thread004-1.2 {
+
+  set ThreadOne {
+    set iStart [clock_seconds]
+    while {[clock_seconds]<$iStart+20} {
+      set ::DB [sqlite3_open test.db]
+      sqlite3_close $::DB
+    }
+  }
+  set ThreadTwo {
+    set ::DB [sqlite3_open test.db]
+    set iStart [clock_seconds]
+    set nErr 0
+    while {[clock_seconds] <$iStart+20} {
+      incr nErr [catch {sqlite3_table_column_metadata $::DB main t1 a}]
+    }
+    sqlite3_close $::DB
+    set nErr
+  }
+  
+  # Run two threads. The first thread opens and closes database test.db
+  # repeatedly. Each time this happens, the in-memory schema used by
+  # all connections to test.db is discarded.
+  #
+  # The second thread calls sqlite3_table_column_metadata() over and
+  # over again. Each time it is called, the database schema is loaded
+  # if it is not already in memory. At one point this was crashing.
+  #
+  unset -nocomplain finished
+  thread_spawn finished(1) $thread_procs $ThreadOne
+  thread_spawn finished(2) $thread_procs $ThreadTwo
+  
+  foreach t {1 2} {
+    if {![info exists finished($t)]} { vwait finished($t) }
+  }
+
+  set finished(2)
+} {0}
+sqlite3_enable_shared_cache $::enable_shared_cache
+finish_test