Import SQLite 3.8.7.4.

third_party/sqlite/patches/0006-Modify-default-VFS-to-support-WebDatabase.patch

-From 25f1f784320aa0e32b69f78098b652b30df40865 Mon Sep 17 00:00:00 2001
-From: dumi <dumi@chromium.org>
-Date: Mon, 20 Jul 2009 23:40:51 +0000
-Subject: [PATCH 06/23] Modify default VFS to support WebDatabase.
-
-The renderer WebDatabase implementation needs to broker certain requests
-to the browser.  This modifies SQLite to allow monkey-patching the VFS
-to support this.
-
-NOTE(shess): This patch relies on core SQLite implementation details
-remaining unchanged.  When importing a new version of SQLite, pay very
-close attention to whether the change is still doing what is intended.
-
-Original review URLs:
-https://codereview.chromium.org/159044
-https://codereview.chromium.org/384075
-https://codereview.chromium.org/377039
-[Possibly not a complete list.]
----
- third_party/sqlite/src/src/os_unix.c | 98 +++++++++++++++++++++++++++++-------
- third_party/sqlite/src/src/os_win.c  |  7 +++
- 2 files changed, 88 insertions(+), 17 deletions(-)
-
-diff --git a/third_party/sqlite/src/src/os_unix.c b/third_party/sqlite/src/src/os_unix.c
-index 998e353..766b52a 100644
---- a/third_party/sqlite/src/src/os_unix.c
-+++ b/third_party/sqlite/src/src/os_unix.c
-@@ -4418,9 +4418,16 @@ typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
- */
- 
- /*
-+** Initializes a unixFile structure with zeros.
-+*/
-+void initUnixFile(sqlite3_file* file) {
-+  memset(file, 0, sizeof(unixFile));
-+}
-+
-+/*
- ** Initialize the contents of the unixFile structure pointed to by pId.
- */
--static int fillInUnixFile(
-+int fillInUnixFile(
-   sqlite3_vfs *pVfs,      /* Pointer to vfs object */
-   int h,                  /* Open file descriptor of file being opened */
-   int dirfd,              /* Directory file descriptor */
-@@ -4834,6 +4841,73 @@ static int findCreateFileMode(
- }
- 
- /*
-+** Initializes a unixFile structure with zeros.
-+*/
-+void chromium_sqlite3_initialize_unix_sqlite3_file(sqlite3_file* file) {
-+  memset(file, 0, sizeof(unixFile));
-+}
-+
-+int chromium_sqlite3_fill_in_unix_sqlite3_file(sqlite3_vfs* vfs,
-+                                               int fd,
-+                                               int dirfd,
-+                                               sqlite3_file* file,
-+                                               const char* fileName,
-+                                               int noLock,
-+                                               int isDelete) {
-+  return fillInUnixFile(vfs, fd, dirfd, file, fileName, noLock, isDelete, 0);
-+}
-+
-+/*
-+** Search for an unused file descriptor that was opened on the database file.
-+** If a suitable file descriptor if found, then it is stored in *fd; otherwise,
-+** *fd is not modified.
-+**
-+** If a reusable file descriptor is not found, and a new UnixUnusedFd cannot
-+** be allocated, SQLITE_NOMEM is returned. Otherwise, SQLITE_OK is returned.
-+*/
-+int chromium_sqlite3_get_reusable_file_handle(sqlite3_file* file,
-+                                              const char* fileName,
-+                                              int flags,
-+                                              int* fd) {
-+  unixFile* unixSQLite3File = (unixFile*)file;
-+  int fileType = flags & 0xFFFFFF00;
-+  if (fileType == SQLITE_OPEN_MAIN_DB) {
-+    UnixUnusedFd *unusedFd = findReusableFd(fileName, flags);
-+    if (unusedFd) {
-+      *fd = unusedFd->fd;
-+    } else {
-+      unusedFd = sqlite3_malloc(sizeof(*unusedFd));
-+      if (!unusedFd) {
-+        return SQLITE_NOMEM;
-+      }
-+    }
-+    unixSQLite3File->pUnused = unusedFd;
-+  }
-+  return SQLITE_OK;
-+}
-+
-+/*
-+** Marks 'fd' as the unused file descriptor for 'pFile'.
-+*/
-+void chromium_sqlite3_update_reusable_file_handle(sqlite3_file* file,
-+                                                  int fd,
-+                                                  int flags) {
-+  unixFile* unixSQLite3File = (unixFile*)file;
-+  if (unixSQLite3File->pUnused) {
-+    unixSQLite3File->pUnused->fd = fd;
-+    unixSQLite3File->pUnused->flags = flags;
-+  }
-+}
-+
-+/*
-+** Destroys pFile's field that keeps track of the unused file descriptor.
-+*/
-+void chromium_sqlite3_destroy_reusable_file_handle(sqlite3_file* file) {
-+  unixFile* unixSQLite3File = (unixFile*)file;
-+  sqlite3_free(unixSQLite3File->pUnused);
-+}
-+
-+/*
- ** Open the file zPath.
- ** 
- ** Previously, the SQLite OS layer used three functions in place of this
-@@ -4921,20 +4995,13 @@ static int unixOpen(
-        || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
-   );
- 
--  memset(p, 0, sizeof(unixFile));
-+  chromium_sqlite3_initialize_unix_sqlite3_file(pFile);
- 
-   if( eType==SQLITE_OPEN_MAIN_DB ){
--    UnixUnusedFd *pUnused;
--    pUnused = findReusableFd(zName, flags);
--    if( pUnused ){
--      fd = pUnused->fd;
--    }else{
--      pUnused = sqlite3_malloc(sizeof(*pUnused));
--      if( !pUnused ){
--        return SQLITE_NOMEM;
--      }
-+    rc = chromium_sqlite3_get_reusable_file_handle(pFile, zName, flags, &fd);
-+    if( rc!=SQLITE_OK ){
-+      return rc;
-     }
--    p->pUnused = pUnused;
-   }else if( !zName ){
-     /* If zName is NULL, the upper layer is requesting a temp file. */
-     assert(isDelete && !isOpenDirectory);
-@@ -4984,10 +5051,7 @@ static int unixOpen(
-     *pOutFlags = flags;
-   }
- 
--  if( p->pUnused ){
--    p->pUnused->fd = fd;
--    p->pUnused->flags = flags;
--  }
-+  chromium_sqlite3_update_reusable_file_handle(pFile, fd, flags);
- 
-   if( isDelete ){
- #if OS_VXWORKS
-@@ -5090,7 +5154,7 @@ static int unixOpen(
-                       isDelete, isReadonly);
- open_finished:
-   if( rc!=SQLITE_OK ){
--    sqlite3_free(p->pUnused);
-+    chromium_sqlite3_destroy_reusable_file_handle(pFile);
-   }
-   return rc;
- }
-diff --git a/third_party/sqlite/src/src/os_win.c b/third_party/sqlite/src/src/os_win.c
-index c876833..78e58b5 100644
---- a/third_party/sqlite/src/src/os_win.c
-+++ b/third_party/sqlite/src/src/os_win.c
-@@ -2784,4 +2784,11 @@ int sqlite3_os_end(void){
-   return SQLITE_OK;
- }
- 
-+void chromium_sqlite3_initialize_win_sqlite3_file(sqlite3_file* file, HANDLE handle) {
-+  winFile* winSQLite3File = (winFile*)file;
-+  memset(file, 0, sizeof(*file));
-+  winSQLite3File->pMethod = &winIoMethod;
-+  winSQLite3File->h = handle;
-+}
-+
- #endif /* SQLITE_OS_WIN */
--- 
-2.2.1
-