Limit memory usage for sqlite3 fuzzer + move it to sqlite dir.

third_party/sqlite/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//testing/libfuzzer/fuzzer_test.gni")
+
 declare_args() {
   # Controls whether the build should uses the version of sqlite3 library
   # shipped with the system (currently only supported on iOS) or the one
   # shipped with Chromium source.
   use_system_sqlite = is_ios
 }
 
 if (!use_system_sqlite) {
   config("sqlite_warnings") {
     cflags = []
@@ skipping 12 matching lines @@
         #   http://www.sqlite.org/faq.html#q17
         "-Wno-int-to-pointer-cast",
         "-Wno-pointer-to-int-cast",
       ]
     }
   }
 
   # "sqlite3" can cause conflicts with the system library.
   component("chromium_sqlite3") {
     visibility = [ ":*" ]
-
     sources = [
       "amalgamation/config.h",
       "amalgamation/sqlite3.c",
       "amalgamation/sqlite3.h",
       "src/src/recover.c",
       "src/src/recover.h",
       "src/src/recover_varint.c",
     ]
 
     cflags = []
@@ skipping 74 matching lines @@
         "fdatasync=fdatasync",
       ]
     }
 
     # Pull in config.h on Linux.  This allows use of preprocessor macros which
     # are not available to the build config.
     if (is_linux) {
       defines += [ "_HAVE_SQLITE_CONFIG_H" ]
     }
 
+    if (use_libfuzzer) {

[mmoroz, 2016/11/11 15:24:05]

That's wrong, we have another flag which should work for more cases (e.g.
use_afl). I'll update this line.

[Scott Hess - ex-Googler, 2016/11/11 15:43:09]

WRT my LGTM, consider it sticky WRT the other code, because I'm not in a
position to consider whether you're using the right gn flag :-).  But using that
to limit the lengths seems reasonable.

+      # Limit max length of data blobs and queries by 128M for fuzzing build.
+      defines += [
+        "SQLITE_MAX_LENGTH=128000000",
+        "SQLITE_MAX_SQL_LENGTH=128000000",
+      ]
+    }
+
     include_dirs = [ "amalgamation" ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
 
       # Must be after no_chromium_code for warning flags to be ordered
       # correctly.
       ":sqlite_warnings",
     ]
@@ skipping 107 matching lines @@
         "//third_party/icu",
       ]
       if (is_clang) {
         # src/ext/icu/icu.c uses assert(!"string") which causes warnings about
         # conversion from string literal to bool.
         configs -= [ "//build/config/clang:extra_warnings" ]
       }
     }
   }
 }
+
+fuzzer_test("sqlite3_prepare_v2_fuzzer") {
+  sources = [
+    "fuzz/sqlite3_prepare_v2_fuzzer.cc",
+  ]
+  deps = [
+    ":sqlite",
+  ]
+  dict = "//testing/libfuzzer/fuzzers/dicts/generated/sqlite3_prepare_v2_fuzzer.dict"
+}