third_party/sqlite/patches/0010-Allow-read-only-memory-mapping.patch

From 12b0ba774b11ae27c41ad20e62522c00567e2a0a Mon Sep 17 00:00:00 2001
From: Scott Hess <shess@chromium.org>
Date: Wed, 5 Aug 2015 16:44:32 -0700
Subject: [PATCH 10/10] Allow read-only memory mapping.

In memory-mapped I/O mode, SQLite writes pages by using memcpy() from
the staging memory into the underlying memory-mapped file.  This allows
anyone in the process to also write into that space.  Modify SQLite to
map things read-only.

TODO: Upstream.

BUG=489784
---
 third_party/sqlite/src/src/os_unix.c | 2 +-
 third_party/sqlite/src/src/os_win.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/third_party/sqlite/src/src/os_unix.c b/third_party/sqlite/src/src/os_unix.c
index fa85638..523cad6 100644
--- a/third_party/sqlite/src/src/os_unix.c
+++ b/third_party/sqlite/src/src/os_unix.c
@@ -3141,7 +3141,7 @@ static int unixRead(
   );
 #endif
 
-#if SQLITE_MAX_MMAP_SIZE>0
+#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
   /* Deal with as much of this read request as possible by transfering
   ** data from the memory mapping using memcpy().  */
   if( offset<pFile->mmapSize ){
diff --git a/third_party/sqlite/src/src/os_win.c b/third_party/sqlite/src/src/os_win.c
index 00ad6fd..8a68828 100644
--- a/third_party/sqlite/src/src/os_win.c
+++ b/third_party/sqlite/src/src/os_win.c
@@ -2524,7 +2524,7 @@ static int winRead(
            "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
            pFile->h, pBuf, amt, offset, pFile->locktype));
 
-#if SQLITE_MAX_MMAP_SIZE>0
+#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
   /* Deal with as much of this read request as possible by transfering
   ** data from the memory mapping using memcpy().  */
   if( offset<pFile->mmapSize ){
-- 
2.7.0